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Cyclic AMP analogs containing hydrophobic modification of C(8) at the adenine ring such as 8-(4-chlorophenylthio)-cAMP (8-pCPT-cAMP) and 8-(4-chlorophenylthio)-2'-O-methyl-cAMP (8-pCPT-2'-O-methyl-cAMP) can penetrate membranes due to their high lipophilicity and directly activate intracellular cAMP effectors. Therefore, these cAMP analogs have been used in numerous studies, assuming that their effects reflect the consequences of direct activation of cAMP effectors. The present study provides evidence that 8-pCPT-modified cAMP analogs and their corresponding putative hydrolysis products (8-(4-chlorophenylthio)-adenosine (8-pCPT-ado) and 8-(4-chlorophenylthio)-2'-O-methyl-adenosine (8-pCPT-2'-O-methyl-ado)) inhibit the equilibrative nucleoside transporter 1 (ENT1). In PC12 cells, in which nucleoside transport strongly depended on ENT1, 8-pCPT-ado, 8-pCPT-2'-O-methyl-ado, and, to a smaller extent, 8-pCPT-2'-O-methyl-cAMP caused an increase of protein kinase A substrate motif phosphorylation and anti-apoptotic effect by an A(2A) adenosine receptor (A(2A)R)-dependent mechanism. In contrast, the effects of 8-pCPT-cAMP were mainly A(2A)R-independent. In HEK 293 showing little endogenous ENT1-dependent nucleoside transport, transfection of ENT1 conferred A(2A)R-dependent increase in protein kinase A substrate motif phosphorylation. Together, the data of the present study indicate that inhibition of ENT1 and activation of adenosine receptors have to be considered when interpreting the effects of 8-pCPT-substituted cAMP/adenosine analogs.
MutLα is essential for human DNA mismatch repair (MMR). It harbors a latent endonuclease, is responsible for recruitment of process associated proteins and is relevant for strand discrimination. Recently, we demonstrated that the MMR function of MutLα is regulated by phosphorylation of MLH1 at serine (S) 477. In the current study, we focused on S87 located in the ATPase domain of MLH1 and on S446, S456 and S477 located in its linker region. We analysed the phosphorylation-dependent impact of these amino acids on DNA binding, MMR ability and thermal stability of MutLα. We were able to demonstrate that phosphorylation at S87 of MLH1 inhibits DNA binding of MutLα. In addition, we detected that its MMR function seems to be regulated predominantly via phosphorylation of serines in the linker domain, which are also partially involved in the regulation of DNA binding. Furthermore, we found that the thermal stability of MutLα decreased in relation to its phosphorylation status implying that complete phosphorylation might lead to instability and degradation of MLH1. In summary, we showed here, for the first time, a phosphorylation-dependent regulation of DNA binding of MutLα and hypothesized that this might significantly impact its functional regulation during MMR in vivo.
Cadmium-mediated toxicity of cultured proximal tubule (PT) cells is associated with increased production of reactive oxygen species (ROS) and apoptosis. We found that cadmium-dependent apoptosis (Hoechst 33342 and annexin V assays) decreased with prolonged CdCl(2) (10 microM) application (controls: 2.4 +/- 1.6%; 5 h: +5.1 +/- 2.3%, 20 h: +5.7 +/- 2.5%, 48 h: +3.3 +/- 1.0% and 72 h: +2.1 +/- 0.4% above controls), while cell proliferation was not affected. Reduction of apoptosis correlated with a time-dependent up-regulation of the drug efflux pump multidrug resistance P-glycoprotein (mdr1) in cadmium-treated cells ( approximately 4-fold after 72 h), as determined by immunoblotting with the monoclonal antibody C219 and measurement of intracellular accumulation of the fluorescent probe calcein +/- the mdr1 inhibitor PSC833 (0.5 microM). When mdr1 inhibitors (PSC833, cyclosporine A, verapamil) were transiently added to cells with mdr1 up-regulation by pretreatment for 72 h with cadmium, cadmium-induced apoptosis increased significantly and to a percentage similar to that obtained in cells with no mdr1 up-regulation (72-h cadmium: 5.2 +/- 0.9% versus 72-h cadmium + 1-h PSC833: 7.2 +/- 1.4%; p < or = 0.001). Cadmium-induced apoptosis and mdr1 up-regulation depended on ROS, since co-incubation with the ROS scavengers N-acetylcysteine (15 mM) or pyrrolidine dithiocarbamate (0.1 mM) abolished both responses. Moreover, cadmium- and ROS-associated mdr1 up-regulation was linked to activation of the transcription factor NF-kappaB; N-acetylcysteine, pyrrolidine dithiocarbamate, and the IkappaB-alpha kinase inhibitor Bay 11-7082 (20 microM) prevented both, mdr1 overexpression and degradation of the inhibitory NF-kappaB subunit, IkappaB-alpha, induced by cadmium. The data show that 1) cadmium-mediated apoptosis in PT cells is associated with ROS production, 2) ROS increase mdr1 expression by a process involving NF-kappaB activation, and 3) mdr1 overexpression protects PT cells against cadmium-mediated apoptosis. These data suggest that mdr1 up-regulation, at least in part, provides anti-apoptotic protection for PT cells against cadmium-mediated stress.
Requirements for the interaction of mouse Polkappa with ubiquitin and its biological significance
(2008)
Polkappa protein is a eukaryotic member of the DinB/Polkappa branch of the Y-family DNA polymerases, which are involved in the tolerance of DNA damage by replicative bypass. Despite universal conservation through evolution, the precise role(s) of Polkappa in this process has remained unknown. Here we report that mouse Polkappa can physically interact with ubiquitin by yeast two-hybrid screening, glutathione S-transferase pulldown, and immunoprecipitation methods. The association of Polkappa with ubiquitin requires the ubiquitin-binding motifs located at the C terminus of Polkappa. In addition, Polkappa binds with monoubiquitinated proliferating cell nuclear antigen (PCNA) more robustly than with non-ubiquitinated PCNA. The ubiquitin-binding motifs mediate the enhanced association between monoubiquitinated PCNA and Polkappa. The ubiquitin-binding motifs are also required for Polkappa to form nuclear foci after UV radiation. However, the ubiquitin-binding motifs do not affect Polkappa half-life. Finally, we have examined levels of Polkappa expression following the exposure of mouse cells to benzo[a]pyrene-dihydrodiol epoxide or UVB radiation.
The iron-sulfur proteins of the cytochrome bc1 complexes of Schizosaccharomyces pombe and Saccharomyces cerevisiae contain the three amino acid motif RX( downward arrow)(F/L/I)XX(T/S/G)XXXX (downward arrow) that is typical for proteins that are cleaved sequentially in two steps by matrix processing peptidase (MPP) and mitochondrial intermediate peptidase (MIP). Despite the presence of this recognition sequence the S. pombe iron-sulfur protein is processed only once during import into mitochondria, whereas the S. cerevisiae protein is processed in two steps. Import of S. pombe iron-sulfur protein in which the putative MIP or MPP recognition sites are eliminated by site-directed mutagenesis and import of iron-sulfur protein into mitochondria from yeast mutants that lack MIP activity indicate that one step processing of the S. pombe iron-sulfur protein is independent of those sites and of MIP activity. Sequencing of the mature protein obtained after import in vitro and of the endogenous iron-sulfur protein isolated from mitochondrial membranes by preparative 2D-electrophoresis shows that MPP recognizes a second site in the presequence and processing occurs between residues 43 and 44. If proline-20 of the S. pombe presequence is changed into a serine, a second cleavage step is induced. Conversely, if serine-24 of the S. cerevisiae presequence is changed to a proline, the first cleavage step that is normally catalyzed by MPP is blocked, causing precursor iron-sulfur protein to accumulate. Together these results indicate that a single amino acid change in the presequence is responsible for one-step processing in S. pombe versus two-step processing in S. cerevisiae.
Respiratory chain complex I contains 8-9 iron-sulfur clusters. In several cases, the assignment of these clusters to subunits and binding motifs is still ambiguous. To test the proposed ligation of the tetranuclear iron-sulfur cluster N5 of respiratory chain complex I, we replaced the conserved histidine 129 in the 75-kDa subunit from Yarrowia lipolytica with alanine. In the mutant strain, reduced amounts of fully assembled but destabilized complex I could be detected. Deamino-NADH: ubiquinone oxidoreductase activity was abolished completely by the mutation. However, EPR spectroscopic analysis of mutant complex I exhibited an unchanged cluster N5 signal, excluding histidine 129 as a cluster N5 ligand.
Stable supercomplexes of bacterial respiratory chain complexes III (ubiquinol:cytochrome c oxidoreductase) and IV (cytochrome c oxidase) have been isolated as early as 1985 (Berry, E. A., and Trumpower, B. L. (1985) J. Biol. Chem. 260, 2458-2467). However, these assemblies did not comprise complex I (NADH:ubiquinone oxidoreductase). Using the mild detergent digitonin for solubilization of Paracoccus denitrificans membranes we could isolate NADH oxidase, assembled from complexes I, III, and IV in a 1:4:4 stoichiometry. This is the first chromatographic isolation of a complete “respirasome.” Inactivation of the gene for tightly bound cytochrome c552 did not prevent formation of this supercomplex, indicating that this electron carrier protein is not essential for structurally linking complexes III and IV. Complex I activity was also found in the membranes of mutant strains lacking complexes III or IV. However, no assembled complex I but only dissociated subunits were observed following the same protocols used for electrophoretic separation or chromatographic isolation of the supercomplex from the wild-type strain. This indicates that the P. denitrificans complex I is stabilized by assembly into the NADH oxidase supercomplex. In addition to substrate channeling, structural stabilization of a membrane protein complex thus appears as one of the major functions of respiratory chain supercomplexes.
Highlights
• USP32 deubiquitinates the Ragulator complex subunit LAMTOR1 at lysine (K) 20
• LAMTOR1 K20 ubiquitination impairs its binding to the vacuolar H+-ATPase
• USP32 knockout reduces mTORC1 activity and elevates autophagic flux
• Depletion of USP32 in Caenorhabditis elegans inhibits mTOR and induces autophagy
Summary
The endosomal-lysosomal system is a series of organelles in the endocytic pathway that executes trafficking and degradation of proteins and lipids and mediates the internalization of nutrients and growth factors to ensure cell survival, growth, and differentiation. Here, we reveal regulatory, non-proteolytic ubiquitin signals in this complex system that are controlled by the enigmatic deubiquitinase USP32. Knockout (KO) of USP32 in primary hTERT-RPE1 cells results among others in hyperubiquitination of the Ragulator complex subunit LAMTOR1. Accumulation of LAMTOR1 ubiquitination impairs its interaction with the vacuolar H+-ATPase, reduces Ragulator function, and ultimately limits mTORC1 recruitment. Consistently, in USP32 KO cells, less mTOR kinase localizes to lysosomes, mTORC1 activity is decreased, and autophagy is induced. Furthermore, we demonstrate that depletion of USP32 homolog CYK-3 in Caenorhabditis elegans results in mTOR inhibition and autophagy induction. In summary, we identify a control mechanism of the mTORC1 activation cascade at lysosomes via USP32-regulated LAMTOR1 ubiquitination.
Deubiquitinases (DUBs) are vital for the regulation of ubiquitin signals, and both catalytic activity of and target recruitment by DUBs need to be tightly controlled. Here, we identify asparagine hydroxylation as a novel posttranslational modification involved in the regulation of Cezanne (also known as OTU domain–containing protein 7B (OTUD7B)), a DUB that controls key cellular functions and signaling pathways. We demonstrate that Cezanne is a substrate for factor inhibiting HIF1 (FIH1)- and oxygen-dependent asparagine hydroxylation. We found that FIH1 modifies Asn35 within the uncharacterized N-terminal ubiquitin-associated (UBA)-like domain of Cezanne (UBACez), which lacks conserved UBA domain properties. We show that UBACez binds Lys11-, Lys48-, Lys63-, and Met1-linked ubiquitin chains in vitro, establishing UBACez as a functional ubiquitin-binding domain. Our findings also reveal that the interaction of UBACez with ubiquitin is mediated via a noncanonical surface and that hydroxylation of Asn35 inhibits ubiquitin binding. Recently, it has been suggested that Cezanne recruitment to specific target proteins depends on UBACez. Our results indicate that UBACez can indeed fulfill this role as regulatory domain by binding various ubiquitin chain types. They also uncover that this interaction with ubiquitin, and thus with modified substrates, can be modulated by oxygen-dependent asparagine hydroxylation, suggesting that Cezanne is regulated by oxygen levels.
Highlights
• Since there is only a low level of evidence, it is difficult to agree on state-of-the-art standards or to provide recommendations and guidelines.
• The value of combining several monitoring devices for dual or triple guidance must be challenged.
• The principle of fascial plane blocks is suitable to avoid traumatic needle-to-nerve contact. However, local toxicity must be regarded as a possible mechanism for nerve injuries.
• Block procedures might be conducted during sedation or general anesthesia when considering the individual patients' clinical situations and the expertise of the anesthesiologist.
• The quality of ultrasound equipment and education provided by the corresponding anesthesia department is highly relevant
Hypoxia potentiates palmitate-induced pro-inflammatory activation of primary human macrophages
(2015)
Pro-inflammatory cytokines secreted by adipose tissue macrophages (ATMs) contribute to chronic low-grade inflammation and obesity-induced insulin resistance. Recent studies have shown that adipose tissue hypoxia promotes an inflammatory phenotype in ATMs. However, our understanding of how hypoxia modulates the response of ATMs to free fatty acids within obese adipose tissue is limited. We examined the effects of hypoxia (1% O2) on the pro-inflammatory responses of human monocyte-derived macrophages to the saturated fatty acid palmitate. Compared with normoxia, hypoxia significantly increased palmitate-induced mRNA expression and protein secretion of IL-6 and IL-1β. Although palmitate-induced endoplasmic reticulum stress and nuclear factor κB pathway activation were not enhanced by hypoxia, hypoxia increased the activation of JNK and p38 mitogen-activated protein kinase signaling in palmitate-treated cells. Inhibition of JNK blocked the hypoxic induction of pro-inflammatory cytokine expression, whereas knockdown of hypoxia-induced transcription factors HIF-1α and HIF-2α alone or in combination failed to reduce IL-6 and only modestly reduced IL-1β gene expression in palmitate-treated hypoxic macrophages. Enhanced pro-inflammatory cytokine production and JNK activity under hypoxia were prevented by inhibiting reactive oxygen species generation. In addition, silencing of dual-specificity phosphatase 16 increased normoxic levels of IL-6 and IL-1β and reduced the hypoxic potentiation in palmitate-treated macrophages. The secretome of hypoxic palmitate-treated macrophages promoted IL-6 and macrophage chemoattractant protein 1 expression in primary human adipocytes, which was sensitive to macrophage JNK inhibition. Our results reveal that the coexistence of hypoxia along with free fatty acids exacerbates macrophage-mediated inflammation.
Conduct Disorder (CD) is an impairing psychiatric disorder of childhood and adolescence characterized by aggressive and dissocial behavior. Environmental factors such as maternal smoking during pregnancy, socio-economic status, trauma, or early life stress are associated with CD. Although the number of females with CD is rising in Western societies, CD is under-researched in female cohorts. We aimed at exploring the epigenetic signature of females with CD and its relation to psychosocial and environmental risk factors. We performed HpaII sensitive genome-wide methylation sequencing of 49 CD girls and 50 matched typically developing controls and linear regression models to identify differentially methylated CpG loci (tags) and regions. Significant tags and regions were mapped to the respective genes and tested for enrichment in pathways and brain developmental processes. Finally, epigenetic signatures were tested as mediators for CD-associated risk factors. We identified a 12% increased methylation 5’ of the neurite modulator SLITRK5 (FDR = 0.0046) in cases within a glucocorticoid receptor binding site. Functionally, methylation positively correlated with gene expression in lymphoblastoid cell lines. At systems-level, genes (uncorr. P < 0.01) were associated with development of neurons, neurite outgrowth or neuronal developmental processes. At gene expression level, the associated gene-networks are activated perinatally and during early childhood in neocortical regions, thalamus and striatum, and expressed in amygdala and hippocampus. Specifically, the epigenetic signatures of the gene network activated in the thalamus during early childhood correlated with the effect of parental education on CD status possibly mediating its protective effect. The differential methylation patterns identified in females with CD are likely to affect genes that are expressed in brain regions previously indicated in CD. We provide suggestive evidence that protective effects are likely mediated by epigenetic mechanisms impairing specific brain developmental networks and therefore exerting a long-term effect on neural functions in CD. Our results are exploratory and thus, further replication is needed.
Background: The understanding of longitudinal changes in the urinary microbiota of healthy women and its relation to intestinal microbiota is limited.
Methods: From a cohort of 15 premenopausal women without known urogenital disease or current symptoms, we collected catheter urine (CU), vaginal and periurethral swabs, and fecal samples on four visits over six months. Additionally, ten participants provided CU and midstream urine (MU) to assess comparability. Urine was subjected to expanded culture. 16S rRNA gene sequencing was performed on all urine, fecal, and selected vaginal and periurethral samples. Sequence reads were processed (DADA2 pipeline) and analyzed using QIIME 2 and R.
Results: Relative abundances of urinary microbiota were variable over 6–18 months. The degree of intraindividual variability of urinary microbiota was higher than that found in fecal samples. Still, nearly half of the observed beta diversity of all urine samples could be attributed to differences between volunteers (R2 = 0.48, p = 0.001). After stratification by volunteer, time since last sexual intercourse was shown to be a factor significantly contributing to beta diversity (R2 = 0.14, p = 0.001). We observed a close relatedness of urogenital microbial habitats and a clear distinction from intestinal microbiota in the overall betadiversity analysis. Microbiota compositions derived from MU differed only slightly from CU compositions. Within this analysis of low-biomass samples, we identified contaminating sequences potentially stemming from sequencing reagents.
Conclusions: Results from our longitudinal cohort study confirmed the presence of a rather variable individual urinary microbiota in premenopausal women. These findings from catheter urine complement previous observations on temporal dynamics in voided urine. The higher intraindividual variability of urinary microbiota as compared to fecal microbiota will be a challenge for future studies investigating associations with urogenital diseases and aiming at identifying pathogenic microbiota signatures.
The Masquelet technique is used to treat large bone defects; it is a two-stage procedure based on an induced membrane. To improve the induced membrane process, demineralized bone matrix in granular (GDBM) and fibrous form (f-DBM) was tested with and without bone marrow mononuclear cells (BMC) as filling of the membrane against the gold standard filling with syngeneic cancellous bone (SCB). A total of 65 male Sprague–Dawley rats obtained a 5 mm femoral defect. These defects were treated with the induced membrane technique and filled with SCB, GDBM, or f-DBM, with or without BMC. After a healing period of eight weeks, the femurs were harvested and submitted for histological, radiological, and biomechanical analyses. The fracture load in the defect zone was lower compared to SCB in all groups. However, histological analysis showed comparable new bone formation, bone mineral density, and cartilage proportions and vascularization. The results suggest that f-DBM in combination with BMC and the induced membrane technique cannot reproduce the very good results of this material in large, non-membrane coated bone defects, nevertheless it supports the maturation of new bone tissue locally. It can be concluded that BMC should be applied in lower doses and inflammatory cells should be removed from the cell preparation before implantation.
Es wurden 34 polyvalente Immunoglobulinpräparate zur i.m. und i.v. Anwendung verschiedener Hersteller und verschiedener Chargen sowie 9 spezifische Tetanus-Immunglobulinpräparate auf das Vorhandensein von HBsAg-Immunkomplexen untersucht. Möglicherweise vorhandene Immunkomplexe wurden vorher mit der sauren Dissoziationsmethode gespalten. Der anschließende Nachweis von HBsAg erfolgte mit dem von uns modifizierten AUSRIA* II-725-Test der Firma Abbot. Von den polyvalenten Immunglobulinen wurden 22 positiv für HBsAg gefunden. Von den spezifischen Immunglobulinen waren 3 positiv.
Standard values of the upper body posture in healthy adults with special regard to age, sex and BMI
(2023)
In order to classify and analyze the parameters of upper body posture in clinical or physiotherapeutic settings, a baseline in the form of standard values with special regard to age, sex and BMI is required. Thus, subjectively healthy men and women aged 21–60 years were measured in this project. The postural parameters of 800 symptom-free male (n = 397) and female (n = 407) volunteers aged 21–60 years (Ø♀: 39.7 ± 11.6, Ø ♂: 40.7 ± 11.5 y) were studied. The mean height of the men was 1.8 ± 0.07 m, with a mean body weight of 84.8 ± 13.1 kg and an average BMI of 26.0 ± 3.534 kg/m2. In contrast, the mean height of the women was 1.67 ± 0.06 m, with a mean body weight of 66.5 ± 12.7 kg and an average BMI of 23.9 ± 4.6 kg/m2. By means of video rasterstereography, a 3-dimensional scan of the upper back surface was measured when in a habitual standing position. The means or medians, confidence intervals, tolerance ranges, the minimum, 2.5, 25, 50, 75, 97.5 percentiles and the maximum, plus the kurtosis and skewness of the distribution, were calculated for all parameters. Additionally, ANOVA and a factor analyses (sex, BMI, age) were conducted. In both sexes across all age groups, balanced, symmetrical upper body statics were evident. Most strikingly, the females showed greater thoracic kyphosis and lumbar lordosis angles (kyphosis: Ø ♀ 56°, Ø♂ 51°; lordosis: Ø ♀ 49°, Ø♂ 32°) and lumbar bending angles (Ø ♀ 14°, Ø♂ 11°) than the males. The distance between the scapulae was more pronounced in men. These parameters also show an increase with age and BMI, respectively. Pelvic parameters were independent of age and sex. The upper body postures of women and men between the ages of 21 and 60 years were found to be almost symmetrical and axis-conforming with a positive correlation for BMI or age. Consequently, the present body posture parameters allow for comparisons with other studies, as well as for the evaluation of clinical (interim) diagnostics and applications.
We have investigated the role of reactive oxygen species and thiol-oxidizing agents in the induction of cell death and have shown that adenocarcinoma gastric (AGS) cells respond differently to the oxidative challenge according to the signaling pathways activated. In particular, apoptosis in AGS cells is induced via the mitochondrial pathway upon treatment with thiol-oxidizing agents, such as diamide. Apoptosis is associated with persistent oxidative damage, as evidenced by the increase in carbonylated proteins and the expression/activation of DNA damage-sensitive proteins histone H2A.X and DNA-dependent protein kinase. Resistance to hydrogen peroxide is instead associated with Keap1 oxidation and rapid translocation of Nrf2 into the nucleus. Sensitivity to diamide and resistance to hydrogen peroxide are correlated with GSH redox changes, with diamide severely increasing GSSG, and hydrogen peroxide transiently inducing protein-GSH mixed disulfides. We show that p53 is activated in response to diamide treatment by the oxidative induction of the Trx1/p38(MAPK) signaling pathway. Similar results were obtained with another carcinoma cell line, CaCo2, indicating that these findings are not limited to AGS cells. Our data suggest that thiol-oxidizing agents could be exploited as inducers of apoptosis in tumor histotypes resistant to ROS-producing chemotherapeutics.
Thioredoxin 1 and thioredoxin 2 have opposed regulatory functions on hypoxia-inducible factor-1α
(2007)
Hypoxia inducible factor 1 (HIF-1), a key regulator for adaptation to hypoxia, is composed of HIF-1alpha and HIF-1beta. In this study, we present evidence that overexpression of mitochondria-located thioredoxin 2 (Trx2) attenuated hypoxia-evoked HIF-1alpha accumulation, whereas cytosolic thioredoxin 1 (Trx1) enhanced HIF-1alpha protein amount. Transactivation of HIF-1 is decreased by overexpression of Trx2 but stimulated by Trx1. Inhibition of proteasomal degradation of HIF-1alpha in Trx2-overexpressing cells did not fully restore HIF-1alpha protein levels, while HIF-1alpha accumulation was enhanced in Trx1-overexpressing cells. Reporter assays showed that cap-dependent translation is increased by Trx1 and decreased by Trx2, whereas HIF-1alpha mRNA levels remained unaltered. These data suggest that thioredoxins affect the synthesis of HIF-1alpha. Trx1 facilitated synthesis of HIF-1alpha by activating Akt, p70S6K, and eIF-4E, known to control cap-dependent translation. In contrast, Trx2 attenuated activities of Akt, p70S6K, and eIF-4E and provoked an increase in mitochondrial reactive oxygen species production. MitoQ, a mitochondria specific antioxidant, reversed HIF-1alpha accumulation as well as Akt activation under hypoxia in Trx2 cells, supporting the notion of translation control mechanisms in affecting HIF-1alpha protein accumulation.
The activation of the transcription factor NF-E2-related factor 2 (Nrf2) maintains cellular homeostasis in response to oxidative stress by the regulation of multiple cytoprotective genes. Without stressors, the activity of Nrf2 is inhibited by its interaction with the Keap1 (kelch-like ECH-associated protein 1). Here, we describe (3S)-1-[4-[(2,3,5,6-tetramethylphenyl) sulfonylamino]-1-naphthyl]pyrrolidine-3-carboxylic acid (RA839), a small molecule that binds noncovalently to the Nrf2-interacting kelch domain of Keap1 with a Kd of ∼6 μm, as demonstrated by x-ray co-crystallization and isothermal titration calorimetry. Whole genome DNA arrays showed that at 10 μm RA839 significantly regulated 105 probe sets in bone marrow-derived macrophages. Canonical pathway mapping of these probe sets revealed an activation of pathways linked with Nrf2 signaling. These pathways were also activated after the activation of Nrf2 by the silencing of Keap1 expression. RA839 regulated only two genes in Nrf2 knock-out macrophages. Similar to the activation of Nrf2 by either silencing of Keap1 expression or by the reactive compound 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid methyl ester (CDDO-Me), RA839 prevented the induction of both inducible nitric-oxide synthase expression and nitric oxide release in response to lipopolysaccharides in macrophages. In mice, RA839 acutely induced Nrf2 target gene expression in liver. RA839 is a selective inhibitor of the Keap1/Nrf2 interaction and a useful tool compound to study the biology of Nrf2.
Resting state fMRI has been employed to identify alterations in functional connectivity within or between brain regions following acute and chronic exposure to Δ9-tetrahydrocannabinol (THC), the psychoactive component in cannabis. Most studies focused a priori on a limited number of local brain areas or circuits, without considering the impact of cannabis on whole-brain network organization. The present study attempted to identify changes in the whole-brain human functional connectome as assessed with ultra-high field (7T) resting state scans of cannabis users (N = 26) during placebo and following vaporization of cannabis. Two distinct data-driven methodologies, i.e. network-based statistics (NBS) and connICA, were used to identify changes in functional connectomes associated with acute cannabis intoxication and history of cannabis use. Both methodologies revealed a broad state of hyperconnectivity within the entire range of major brain networks in chronic cannabis users compared to occasional cannabis users, which might be reflective of an adaptive network reorganization following prolonged cannabis exposure. The connICA methodology also extracted a distinct spatial connectivity pattern of hypoconnectivity involving the dorsal attention, limbic, subcortical and cerebellum networks and of hyperconnectivity between the default mode and ventral attention network, that was associated with the feeling of subjective high during THC intoxication. Whole-brain network approaches identified spatial patterns in functional brain connectomes that distinguished acute from chronic cannabis use, and offer an important utility for probing the interplay between short and long-term alterations in functional brain dynamics when progressing from occasional to chronic use of cannabis.
Ataxia telangiectasia (A-T) is a progressive and life-limiting disease associated with cerebellar ataxia due to progressive cerebellar degeneration. In addition to ataxia, which is described in detail, the presence of chorea, dystonia, oculomotor apraxia, athetosis, parkinsonism, and myoclonia are typical manifestations of the disease. The study aimed to evaluate the specificity and sensitivity of neurofilament light chain (NfL) as a biomarker of neurodegeneration in relation to SARA score. In this prospective trial, one visit of 42 A-T patients aged 1.3–25.6 years (mean 11.6 ± 7.3 years) was performed, in which NfL was determined from serum by ELISA. Additionally, a neurological examination of the patients was performed. Blood was collected from 19 healthy volunteers ≥ 12 years of age. We found significantly increased levels of NfL in patients with A-T compared to healthy controls (21.5 ± 3.6 pg/mL vs. 9.3 ± 0.49 pg/mL, p ≤ 0.01). There was a significant correlation of NfL with age, AFP, and SARA. NfL is a new potential progression biomarker in blood for neurodegeneration in A-T which increases with age.
Background: The correct performance of a structured facial examination presents a fundamental clinical skill to detect facial pathologies. However, many students are not adequately prepared in this basic clinical skill. Many argue that the traditional ‘See One, Do One’ approach is not sufficient to fully master a clinical skill. ‘Mental Training’ has successfully been used to train psychomotor and technical skills in sports and other surgical fields, but its use in Oral and Maxillofacial Surgery is not described. We conducted a quasi-experimental to determine if ‘Mental Training’ was effective in teaching a structured facial examination.
Methods: Sixty-seven students were randomly assigned to a ‘Mental Training’ and ‘See One, Do One’ group. Both groups received standardized video instruction on how to perform a structured facial examination. The ‘See One, Do One’ group then received 60 min of guided physical practice while the ‘Mental Training’ group actively developed a detailed, stepwise sequence of the performance of a structured facial examination and visualized this sequence subvocally before practicing the skill. Student performance was measured shortly after (T1) and five to 10 weeks (T2) after the training by two blinded examiners (E1 and E2) using a validated checklist.
Results: Groups did not differ in gender, age or in experience. The ‘Mental Training’ group averaged significantly more points in T1 (pE1 = 0.00012; pE2 = 0.004; dE1 = 0.86; dE2 = 0.66) and T2 (pE1 = 0.04; pE2 = 0.008, dE1 = 0.37; dE2 = 0.64) than the ‘See One, Do One’ group. The intragroup comparison showed a significant (pE1 = 0.0002; pE2 = 0.06, dE1 = 1.07; dE2 = 0.50) increase in clinical examination skills in the ‘See One, Do One’ group, while the ‘Mental Training’ group maintained an already high level of clinical examination skills between T1 and T2.
Discussion: ‘Mental Training’ is an efficient tool to teach and maintain basic clinical skills. In this study ‘Mental Training’ was shown to be superior to the commonly used ‘See One, Do One’ approach in learning how to perform a structured facial examination and should therefore be considered more often to teach physical examination skills.
Assessment of individual therapeutic responses provides valuable information concerning treatment benefits in individual patients. We evaluated individual therapeutic responses as determined by the Disease Activity Score-28 joints critical difference for improvement (DAS28-dcrit) in rheumatoid arthritis (RA) patients treated with intravenous tocilizumab or comparator anti-tumor necrosis factor (TNF) agents. The previously published DAS28-dcrit value [DAS28 decrease (improvement) ≥ 1.8] was retrospectively applied to data from two studies of tocilizumab in RA, the 52-week ACT-iON observational study and the 24-week ADACTA randomized study. Data were compared within (not between) studies. DAS28 was calculated with erythrocyte sedimentation rate as the inflammatory marker. Stability of DAS28-dcrit responses and European League Against Rheumatism (EULAR) good responses was determined by evaluating repeated responses at subsequent timepoints. A logistic regression model was used to calculate p values for differences in response rates between active agents. Patient-reported outcomes (PROs; pain, global health, function, and fatigue) in DAS28-dcrit responder versus non-responder groups were compared with an ANCOVA model. DAS28-dcrit individual response rates were 78.2% in tocilizumab-treated patients and 58.2% in anti-TNF-treated patients at week 52 in the ACT-ion study (p = 0.0001) and 90.1% versus 59.1% at week 24 in the ADACTA study (p < 0.0001). DAS28-dcrit responses showed greater stability over time (up to 52 weeks) than EULAR good responses. For both active treatments, DAS28-dcrit responses were associated with statistically significant improvements in mean PRO values compared with non-responders. The DAS28-dcrit response criterion provides robust assessments of individual responses to RA therapy and may be useful for discriminating between active agents in clinical studies and guiding treat-to-target decisions in daily practice.
Human RNF213, which encodes the protein mysterin, is a known susceptibility gene for moyamoya disease (MMD), a cerebrovascular condition with occlusive lesions and compensatory angiogenesis. Mysterin mutations, together with exposure to environmental trigger factors, lead to an elevated stroke risk since childhood. Mysterin is induced during cell stress, to function as cytosolic AAA+ ATPase and ubiquitylation enzyme. Little knowledge exists, in which context mysterin is needed. Here, we found that genetic ablation of several mitochondrial matrix factors, such as the peptidase ClpP, the transcription factor Tfam, as well as the peptidase and AAA+ ATPase Lonp1, potently induces Rnf213 transcript expression in various organs, in parallel with other components of the innate immune system. Mostly in mouse fibroblasts and human endothelial cells, the Rnf213 levels showed prominent upregulation upon Poly(I:C)-triggered TLR3-mediated responses to dsRNA toxicity, as well as upon interferon gamma treatment. Only partial suppression of Rnf213 induction was achieved by C16 as an antagonist of PKR (dsRNA-dependent protein kinase). Since dysfunctional mitochondria were recently reported to release immune-stimulatory dsRNA into the cytosol, our results suggest that mysterin becomes relevant when mitochondrial dysfunction or infections have triggered RNA-dependent inflammation. Thus, MMD has similarities with vasculopathies that involve altered nucleotide processing, such as Aicardi-Goutières syndrome or systemic lupus erythematosus. Furthermore, in MMD, the low penetrance of RNF213 mutations might be modified by dysfunctions in mitochondria or the TLR3 pathway.
Purpose: Neonatal surgery for abdominal wall defects is not performed in a centralized manner in Germany. The aim of this study was to investigate whether treatment for abdominal wall defects in Germany is equally effective compared to international results despite the decentralized care.
Methods: All newborn patients who were clients of the major statutory health insurance company in Germany between 2009 and 2013 and who had a diagnosis of gastroschisis or omphalocele were included. Mortality during the first year of life was analysed.
Results: The 316 patients with gastroschisis were classified as simple (82%) or complex (18%) cases. The main associated anomalies in the 197 patients with omphalocele were trisomy 18/21 (8%), cardiac anomalies (32%) and anomalies of the urinary tract (10%). Overall mortality was 4% for gastroschisis and 16% for omphalocele. Significant factors for non-survival were birth weight below 1500 g for both groups, complex gastroschisis, volvulus and anomalies of the blood supply to the intestine in gastroschisis, and female gender, trisomy 18/21 and lung hypoplasia in omphalocele.
Conclusions: Despite the fact that paediatric surgical care is organized in a decentralized manner in Germany, the mortality rates for gastroschisis and omphalocele are equal to those reported in international data.
This study highlights the importance of insect evidence by evaluating 949 insect-associated cases, including 139 entomological reports, from 2001 to 2019 at the Institute of Legal Medicine Frankfurt/Germany. With a high number of cases in the summer months and a low number in the colder season, 78.5% of the bodies were found indoors, regardless of year or month. In more than 80% of the cases, where PMI information was available (n = 704), the presumed PMI ranged from 1 to 21 days, a period during which entomological evidence can provide a day-specific estimate of PMImin. In cases where insects have been identified to species level (n = 279), most bodies were infested by one or two species with a maximum of 10 different species. Overall, a total of 55 insect species were found. Information on biology, activity and distribution of the most abundant taxa is given and applied for 5 case histories estimating different PMImins of up to over 6 months. Despite proved importance and scientific development of forensic entomology, insects are still rarely considered as a tool in forensic case work. The main reasons are a lack of awareness and (too) late involvement of a forensic entomologist. Our work shows that forensic entomology is an independent discipline that requires specialist expertise.
Purpose of Review: To provide an overview of current surgical peri-implantitis treatment options.
Recent Findings: Surgical procedures for peri-implantitis treatment include two main approaches: non-augmentative and augmentative therapy. Open flap debridement (OFD) and resective treatment are non-augmentative techniques that are indicated in the presence of horizontal bone loss in aesthetically nondemanding areas. Implantoplasty performed adjunctively at supracrestally and buccally exposed rough implant surfaces has been shown to efficiently attenuate soft tissue inflammation compared to control sites. However, this was followed by more pronounced soft tissue recession. Adjunctive augmentative measures are recommended at peri-implantitis sites exhibiting intrabony defects with a minimum depth of 3 mm and in the presence of keratinized mucosa. In more advanced cases with combined defect configurations, a combination of augmentative therapy and implantoplasty at exposed rough implant surfaces beyond the bony envelope is feasible.
Summary: For the time being, no particular surgical protocol or material can be considered as superior in terms of long-term peri-implant tissue stability.
Purpose of Review: Attention deficit hyperactivity disorder (ADHD) shows high heritability in formal genetic studies. In our review article, we provide an overview on common and rare genetic risk variants for ADHD and their link to clinical practice.
Recent findings: The formal heritability of ADHD is about 80% and therefore higher than most other psychiatric diseases. However, recent studies estimate the proportion of heritability based on singlenucleotide variants (SNPs) at 22%. It is a matter of debate which genetic mechanisms explain this huge difference. While frequent variants in first mega-analyses of genome-wideassociation study data containing several thousand patients give the first genome-wide results, explaining only little variance, the methodologically more difficult analyses of rare variants are still in their infancy. Some rare genetic syndromes show higher prevalence for ADHD indicating a potential role for a small number of patients. In contrast, polygenic risk scores (PRS) could potentially be applied to every patient. We give an overview how PRS explain different behavioral phenotypes in ADHD and how they could be used for diagnosis and therapy prediction.
Summary: Knowledge about a patient’s genetic makeup is not yet mandatory for ADHD therapy or diagnosis. PRS however have been introduced successfully in other areas of clinical medicine, and their application in psychiatry will begin within the next years. In order to ensure competent advice for patients, knowledge of the current state of research is useful forpsychiatrists.
Despite the implementation of consolidative immune checkpoint inhibition after definitive chemoradiotherapy (CRT), the prognosis for locally advanced non-small-cell lung cancer (NSCLC) remains poor. We assessed the impact of the C-reactive protein (CRP) to albumin ratio (CAR) as an inflammation-based prognostic score in patients with locally advanced NSCLC treated with CRT. We retrospectively identified and analyzed 52 patients with primary unresectable NSCLC (UICC Stage III) treated with definitive/neoadjuvant CRT between 2014 and 2019. CAR was calculated by dividing baseline CRP by baseline albumin levels and correlated with clinicopathologic parameters to evaluate prognostic impact. After dichotomizing patients by the median, univariate and multivariate Cox regression analyses were performed. An increased CAR was associated with advanced T-stage (p = 0.018) and poor performance status (p = 0.004). Patients with pre-therapeutic elevated CAR had significantly lower hemoglobin and higher leukocyte levels (hemoglobin p = 0.001, leukocytes p = 0.018). High baseline CAR was shown to be associated with worse local control (LPFS, p = 0.006), shorter progression-free survival (PFS, p = 0.038) and overall survival (OS, p = 0.022), but not distant metastasis-free survival (DMFS). Multivariate analysis confirmed an impaired outcome in patients with high CAR (LPFS: HR 3.562, 95% CI 1.294–9.802, p = 0.011). CAR is an easily available and independent prognostic marker after CRT in locally advanced NSCLC. CAR may be a useful biomarker for patient stratification to individualize treatment concepts.
Calcium (Ca2+) elevation is an essential secondary messenger in many cellular processes, including disease progression and adaptation to external stimuli, e.g., gravitational load. Therefore, mapping and quantifying Ca2+ signaling with a high spatiotemporal resolution is a key challenge. However, particularly on microgravity platforms, experiment time is limited, allowing only a small number of replicates. Furthermore, experiment hardware is exposed to changes in gravity levels, causing experimental artifacts unless appropriately controlled. We introduce a new experimental setup based on the fluorescent Ca2+ reporter CaMPARI2, onboard LED arrays, and subsequent microscopic analysis on the ground. This setup allows for higher throughput and accuracy due to its retrograde nature. The excellent performance of CaMPARI2 was demonstrated with human chondrocytes during the 75th ESA parabolic flight campaign. CaMPARI2 revealed a strong Ca2+ response triggered by histamine but was not affected by the alternating gravitational load of a parabolic flight.
Acute respiratory distress syndrome (ARDS) is a major cause of patient mortality in intensive care units (ICUs) worldwide. Considering that no causative treatment but only symptomatic care is available, it is obvious that there is a high unmet medical need for a new therapeutic concept. One reason for a missing etiologic therapy strategy is the multifactorial origin of ARDS, which leads to a large heterogeneity of patients. This review summarizes the various kinds of ARDS onset with a special focus on the role of reactive oxygen species (ROS), which are generally linked to ARDS development and progression. Taking a closer look at the data which already have been established in mouse models, this review finally proposes the translation of these results on successful antioxidant use in a personalized approach to the ICU patient as a potential adjuvant to standard ARDS treatment.
Renal glomerular diseases such as glomerulosclerosis and diabetic nephropathy often result in the loss of glomerular function and consequently end-stage renal disease. The glomerulus consists of endothelial cells, mesangial cells and glomerular epithelial cells also referred to as podocytes. A fine-tuned crosstalk between glomerular cells warrants control of growth factor synthesis and of matrix production and degradation, preserving glomerular structure and function. Hydrogen sulfide (H2S) belongs together with nitric oxide (NO) and carbon monoxide (CO) to the group of gasotransmitters. During the last three decades, these higher concentration toxic gases have been found to be produced in mammalian cells in a well-coordinated manner. Recently, it became evident that H2S and the other gasotransmitters share common targets as signalling devices that trigger mainly protective pathways. In several animal models, H2S has been demonstrated as a protective factor in the context of kidney disorders, in particular of diabetic nephropathy. Here, we focus on the synthesis and action of H2S in glomerular cells, its beneficial effects in the glomerulus and its action in the context of the other gaseous signalling molecules NO and CO.
Macrophages constitute a major part of the tumor-infiltrating immune cells. Within the tumor microenvironment, they acquire an alternatively activated, tumor-supporting phenotype. Factors released by tumor cells are crucial for the recruitment of tumor-associated macrophages. In the present project, we aimed to understand the role of hsa-miR-200c-3p (miR-200c) in the interplay between tumor cells and macrophages. To this end, we employed a coculture system of MCF7 breast tumor cells and primary human macrophages and observed the transfer of miR-200c from apoptotic tumor cells to macrophages, which required intact CD36 receptor in macrophages. We further comprehensively determined miR-200c targets in macrophages by mRNA-sequencing and identified numerous migration-associated mRNAs to be downregulated by miR-200c. Consequently, miR-200c attenuated macrophage infiltration into 3-dimensional tumor spheroids. miR-200c-mediated reduction in infiltration further correlated with a miR-200c migration signature comprised of the four miR-200c-repressed, predicted targets PPM1F, RAB11FIB2, RDX, and MSN.
Physical activity and well-being during the second COVID19-related lockdown in Germany in 2021
(2021)
In the second wave of the COVID-19 pandemic in Germany, lockdown measures were reinstalled and were in place between November 2020 and April 2021, including the closure of physical activity facilities. The aim of the current online survey was to assess the lockdown effects on physical activity and well-being in the general population. Pre-lockdown vs. lockdown differences were tested with the Χ2 test and the Student’s t-test for paired data. Predictor variables to explain compliance with physical activity recommendations were identified using a fixed-effects binary logistic regression analysis. Data of 993 respondents were analyzed. Transport-related and leisure-time physical activity decreased (p < 0.001, d = 0.25, and p < 0.001, d = 0.33, respectively). Compliance with physical activity recommendations decreased from 42.2% to 29.4% (chi2 (1, 1986) = 35.335, p < 0.001, V = 0.13). Well-being decreased significantly (t (990) = 23.405, p < 0.001) by 16.3 points (d = 0.74). Physical activity and well-being declined in German adults during the second COVID-19-related lockdown. Physical activity should be promoted also in light of the emerging evidence on its protective effects against COVID-19.
Background and Objectives: We tested if a novel combination of predictors could improve the accuracy of outcome prediction after transfemoral transcatheter aortic valve implantation (TAVI). Materials and Methods: This prospective study recruited 169 participants (49% female; median age 81 years). The primary endpoint was midterm mortality; secondary endpoints were acute Valve Academic Research Consortium (VARC)-3 complication rate and post-TAVI in-hospital length of stay (LoS). EuroSCORE II (ESII), comorbidities (e.g., coronary artery disease), eGFR (estimated glomerular filtration rate; based on cystatin C), hemoglobin, creatinine, N-Terminal pro-Brain Natriuretic Peptide (NTproBNP) levels and patient-reported outcome measures (PROMs, namely EuroQol-5-Dimension-5-Levels, EQ5D5L; Kansas City Cardiomyopathy Questionnaire, KCCQ; clinical frailty scale, CFS) at baseline were tested as predictors. Regression (uni- and multi-variate Cox; linear; binary logistic) and receiver operating characteristic (ROC)-curve analysis were applied. Results: Within a median follow-up of 439 (318–585) days, 12 participants died (7.1%). Independent predictors of mortality using multivariate Cox regression were baseline eGFR (p = 0.001) and KCCQ (p = 0.037). Based on these predictors, a Linear Prediction Score (LPS1) was calculated. The LPS1-area under the curve (AUC)-value (0.761) was significantly higher than the ESII-AUC value (0.597; p = 0.035). Independent predictors for LoS > 6 days (the median LoS) were eGFR (p = 0.028), NTproBNP (p = 0.034), and EQ5D5L values (p = 0.002); a respective calculated LPS2 provided an AUC value of 0.677 (p < 0.001). Eighty participants (47.3%) experienced complications. Male sex predicted complications only in the univariate analysis. Conclusions: The combination of KCCQ and eGFR can better predict midterm mortality than ES II alone. Combining eGFR, NTproBNP, and EQ5D5L can reliably predict LoS after TAVI. This novel method improves personalized TAVI risk stratification and hence may help reduce post-TAVI risk.
Cellular response of human osteoblasts to different presentations of deproteinized bovine bone
(2022)
Objectives: This study evaluated the cellular response of primary osteoblasts exposed to two different presentations of a low-temperature non-sintered deproteinized bovine bone matrix (DBBM). Materials and methods: Six different baths of a commercially available DBBM block (Bonefill® Porous Block) and one of DBBM granule (Bonefill® Porous) were evaluated to identify the mineral structure and organic or cellular remnants. Samples of the same baths were processed in TRIZOL for RNA extraction and quantification. For the immunologic cell reaction assay, primary human osteoblasts (pOB) were exposed to DBMM block (pOB + B) or granules (pOB + G), or none (control) for 1, 3, or 7 days of cell cultivation. Expression of proinflammatory cytokines by pOB was evaluated by crosslinked ELISA assay. In addition, total DNA amount, as well as cell viability via LDH evaluation, was assessed. Results: Organic remnants were present in DBBM blocks; 45.55% (±7.12) of osteocytes lacunae presented cellular remnants in blocks compared to 17.31% (±1.31) in granules. In three of five batches of blocks, it was possible to isolate bovine RNA. The highest concentration of TGF-β1 was found in supernatants of pOB + G on day 7 (218.85 ± 234.62 pg/mL) (p < 0.05), whereas pOB + B presented the lowest amount of TGF-β1 secretion at the end of evaluation (30.22 ± 14.94 pg/mL, p < 0.05). For IL-6 and OPG, there was no statistical difference between groups, while pOB + G induced more IL-8 secretion than the control (3.03 ± 3.38 ng/mL, p < 0.05). Considering the kinetics of cytokine release during the study period, all groups presented a similar pattern of cytokines, estimated as an increasing concentration for IL-6, IL-8, and OPG during cultivation. Adherent cells were observed on both material surfaces on day 7, according to H&E and OPN staining. Conclusion: Neither tested material induced a pronounced inflammatory response upon osteoblast cultivation. However, further studies are needed to elucidate the potential influence of organic remnants in bone substitute materials on the regeneration process.
Aims: Patients with cardiovascular comorbidities have a significantly increased risk for a critical course of COVID-19. As the SARS-CoV2 virus enters cells via the angiotensin-converting enzyme receptor II (ACE2), drugs which interact with the renin angiotensin aldosterone system (RAAS) were suspected to influence disease severity.
Methods and results: We analyzed 1946 consecutive patients with cardiovascular comorbidities or hypertension enrolled in one of the largest European COVID-19 registries, the Lean European Open Survey on SARS-CoV-2 (LEOSS) registry. Here, we show that angiotensin II receptor blocker intake is associated with decreased mortality in patients with COVID-19 [OR 0.75 (95% CI 0,59–0.96; p = 0.013)]. This effect was mainly driven by patients, who presented in an early phase of COVID-19 at baseline [OR 0,64 (95% CI 0,43–0,96; p = 0.029)]. Kaplan-Meier analysis revealed a significantly lower incidence of death in patients on an angiotensin receptor blocker (ARB) (n = 33/318;10,4%) compared to patients using an angiotensin-converting enzyme inhibitor (ACEi) (n = 60/348;17,2%) or patients who received neither an ACE-inhibitor nor an ARB at baseline in the uncomplicated phase (n = 90/466; 19,3%; p<0.034). Patients taking an ARB were significantly less frequently reaching the mortality predicting threshold for leukocytes (p<0.001), neutrophils (p = 0.002) and the inflammatory markers CRP (p = 0.021), procalcitonin (p = 0.001) and IL-6 (p = 0.049). ACE2 expression levels in human lung samples were not altered in patients taking RAAS modulators.
Conclusion: These data suggest a beneficial effect of ARBs on disease severity in patients with cardiovascular comorbidities and COVID-19, which is linked to dampened systemic inflammatory activity.
Introduction Patients undergoing heart valve surgery are predominantly transferred postoperatively to the intensive care unit (ICU) under continuous sedation. Volatile anaesthetics are an increasingly used treatment alternative to intravenous substances in the ICU. As subject to inhalational uptake and elimination, the resulting pharmacological benefits have been repeatedly demonstrated. Therefore, volatile anaesthetics appear suitable to meet the growing demands of fast-track cardiac surgery. However, their use requires special preparation at the bedside and trained medical and nursing staff, which might limit the pharmacological benefits. The aim of our work is to assess whether the temporal advantages of recovery under volatile sedation outweigh the higher effort of special preparation.
Methods and analysis The study is designed to evaluate the differences between intravenous sedatives (n=48) and volatile sedatives (n=48) in continued intensive care sedation. This study will be conducted as a prospective, randomised, controlled, single-blinded, monocentre trial at a German university hospital in consenting adult patients undergoing heart valve surgery at a university hospital. This observational study will examine the necessary preparation time, staff consultation and overall feasibility of the chosen sedation method. For this purpose, the continuation of sedation in the ICU with volatile sedatives is considered as one study arm and with intravenous sedatives as the comparison group. Due to rapid elimination and quick awakening after the termination of sedation, closer consultation between the attending physician and the ICU nursing staff is required, in addition to a prolonged setup time. Study analysis will include the required setup time, time from admission to extubation as primary outcome and neurocognitive assessability. In addition, possible operation-specific (blood loss, complications), treatment parameters (catecholamine dosages, lung function) and laboratory results (acute kidney injury, acid base balance (lactataemia), liver failure) as influencing factors will be collected. The study-relevant data will be extracted from the continuous digital records of the patient data management system after the patient has been discharged from the ICU. For statistical evaluation, 95% CIs will be calculated for the median time to extubation and neurocognitive assessability, and the association will be assessed with a Cox regression model. In addition, secondary binary outcome measures will be evaluated using Fisher’s exact tests. Further descriptive and exploratory statistical analyses are also planned.
Ethics and dissemination The study was approved by the Institutional Ethics Board of the University of Frankfurt, Germany (#20-1050). Informed consent of all individual patients will be obtained before randomisation. Results will be disseminated via publication in peer-reviewed journals.
Hintergrund: Eine adäquate Anpassung der Glukokortikoidsubstitution an unterschiedliche Situationen ist essenziell für Leistungsfähigkeit und Lebensqualität von Patienten mit Nebennierenrindeninsuffizienz (NNRI). Sie dient darüber hinaus der Vermeidung lebensbedrohlicher adrenaler Krisen.
Ziel der Arbeit: Verbesserung der Versorgung von Patienten mit Nebennierenrindeninsuffizienz.
Material und Methoden: Selektive Literaturrecherche unter besonderer Berücksichtigung neuerer Studien.
Ergebnisse: Eine optimale Glukokortikoidsubstitution hat das Ziel, die physiologischen Kortisolschwankungen möglichst genau nachzuahmen. Hier haben in den letzten Jahren Präparate mit veränderter Pharmakokinetik das Therapiespektrum erweitert. Im Vordergrund stehen eine adäquate Anpassung der Substitution in Stresssituationen sowie die Vermeidung und adäquate Behandlung adrenaler Krisen, die mit einer Inzidenz von 4,8 bis 8,3 Krisen pro 100 Patientenjahre auftreten und mit einer Mortalität von etwa 0,5 pro 100 Patientenjahre weiterhin eine tödliche Bedrohung darstellen.
Schlussfolgerung: Zur Verhinderung lebensbedrohlicher Nebennierenkrisen ist eine Schulung von Patienten, Angehörigen und insbesondere auch medizinischem Personal notwendig.
Autophagy is an important survival mechanism that allows recycling of nutrients and removal of damaged organelles and has been shown to contribute to the proliferation of acute myeloid leukemia (AML) cells. However, little is known about the mechanism by which autophagy- dependent AML cells can overcome dysfunctional autophagy. In our study we identified autophagy related protein 3 (ATG3) as a crucial autophagy gene for AML cell proliferation by conducting a CRISPR/Cas9 dropout screen with a library targeting around 200 autophagy-related genes. shRNA-mediated loss of ATG3 impaired autophagy function in AML cells and increased their mitochondrial activity and energy metabolism, as shown by elevated mitochondrial ROS generation and mitochondrial respiration. Using tracer-based NMR metabolomics analysis we further demonstrate that the loss of ATG3 resulted in an upregulation of glycolysis, lactate production, and oxidative phosphorylation. Additionally, loss of ATG3 strongly sensitized AML cells to the inhibition of mitochondrial metabolism. These findings highlight the metabolic vulnerabilities that AML cells acquire from autophagy inhibition and support further exploration of combination therapies targeting autophagy and mitochondrial metabolism in AML.
Uterine cervical cancer is one of the leading causes of cancer-related mortality in women worldwide. Each year, over half a million new cases are estimated, resulting in more than 300,000 deaths. While less-invasive, fertility-preserving surgical procedures can be offered to women in early stages, treatment for locally advanced disease may include radical hysterectomy, primary chemoradiotherapy (CRT) or a combination of these modalities. Concurrent platinum-based chemoradiotherapy regimens remain the first-line treatments for locally advanced cervical cancer. Despite achievements such as the introduction of angiogenesis inhibitors, and more recently immunotherapies, the overall survival of women with persistent, recurrent or metastatic disease has not been extended significantly in the last decades. Furthermore, a broad spectrum of molecular markers to predict therapy response and survival and to identify patients with high- and low-risk constellations is missing. Implementation of these markers, however, may help to further improve treatment and to develop new targeted therapies. This review aims to provide comprehensive insights into the complex mechanisms of cervical cancer pathogenesis within the context of molecular markers for predicting treatment response and prognosis.
The microtubule (MT) cytoskeleton is crucial for cell motility and migration by regulating multiple cellular activities such as transport and endocytosis of key components of focal adhesions (FA). The kinesin-13 family is important in the regulation of MT dynamics and the best characterized member of this family is the mitotic centromere-associated kinesin (MCAK/KIF2C). Interestingly, its overexpression has been reported to be related to increased metastasis in various tumor entities. Moreover, MCAK is involved in the migration and invasion behavior of various cell types. However, the precise molecular mechanisms were not completely clarified. To address these issues, we generated CRISPR/dCas9 HeLa and retinal pigment epithelium (RPE) cell lines overexpressing or downregulating MCAK. Both up- or downregulation of MCAK led to reduced cell motility and poor migration in malignant as well as benign cells. Specifically, it’s up- or downregulation impaired FA protein composition and phosphorylation status, interfered with a proper spindle and chromosome segregation, disturbed the assembly and disassembly rate of FA, delayed cell adhesion, and compromised the plus-tip dynamics of MTs. In conclusion, our data suggest MCAK act as an important regulator for cell motility and migration by affecting the actin-MT cytoskeleton dynamics and the FA turnover, providing molecular mechanisms by which deregulated MCAK could promote malignant progression and metastasis of tumor cells.
Background: Inflammation, particularly cytokine release, contributes to epileptogenesis by influencing the cerebral tissue remodeling and neuronal excitability that occurs after a precipitating epileptogenic insult. While several cytokines have been explored in this process, release kinetics are less well investigated. Determining the time course of cytokine release in the epileptogenic zone is necessary for precisely timed preventive or therapeutic anti-inflammatory interventions. Methods: Hippocampal extracellular levels of six cytokines and chemokines (IL-1β, IL-6, IL-10, CCL2, CCL3, and CCL5) were quantified at various time points during epileptogenesis in a rat model of mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS) using microdialysis (MD). Results: The analysis of microdialysates demonstrated consistent elevation at all time points during epileptogenesis for IL-1β and IL-10. IL-10 release was maximal on day 1, IL-1β release peaked at day 8. No correlation between local hippocampal IL-1β concentrations and IL-1β blood levels was found. Conclusion: The release kinetics of IL-1β are consistent with its established pro-epileptogenic properties, while the kinetics of IL-10 suggest a counter-regulatory effect. This proof-of-concept study demonstrates the feasibility of intraindividual longitudinal monitoring of hippocampal molecular inflammatory processes via repetitive MD over several weeks and sheds light on the kinetics of hippocampal cytokine release during epileptogenesis.
In recent years, the infrapatellar fat pad (IFP) has gained increasing research interest. The contribution of the IFP to the development and progression of knee osteoarthritis (OA) through extensive interactions with the synovium, articular cartilage, and subchondral bone is being considered. As part of the initiation process of OA, IFP secretes abundant pro-inflammatory mediators among many other factors. Today, the IFP is (partially) resected in most total knee arthroplasties (TKA) allowing better visualization during surgical procedures. Currently, there is no clear guideline providing evidence in favor of or against IFP resection. With increasing numbers of TKAs, there is a focus on preventing adverse postoperative outcomes. Therefore, anatomic features, role in the development of knee OA, and consequences of resecting versus preserving the IFP during TKA are reviewed in the following article.
We proposed previously that closure of voltage-dependent anion channels (VDAC) in the mitochondrial outer membrane after ethanol exposure leads to suppression of mitochondrial metabolite exchange. Because ureagenesis requires extensive mitochondrial metabolite exchange, we characterized the effect of ethanol and its metabolite, acetaldehyde (AcAld), on total and ureagenic respiration in cultured rat hepatocytes. Ureagenic substrates increased cellular respiration from 15.8 ± 0.9 nmol O(2)/min/10(6) cells (base line) to 29.4 ± 1.7 nmol O(2)/min/10(6) cells in about 30 min. Ethanol (0-200 mM) suppressed extra respiration after ureagenic substrates (ureagenic respiration) by up to 51% but not base line respiration. Urea formation also declined proportionately. Inhibition of alcohol dehydrogenase, cytochrome P450 2E1, and catalase with 4-methylpyrazole, trans-1,2-dichloroethylene, and 3-amino-1,2,3-triazole restored ethanol-suppressed ureagenic respiration by 46, 37, and 66%, respectively. By contrast, inhibition of aldehyde dehydrogenase with phenethyl isothiocyanate increased the inhibitory effect of ethanol on ureagenic respiration by an additional 60%. AcAld, an intermediate product of ethanol oxidation, suppressed ureagenic respiration with an apparent IC(50) of 125 μM. AcAld also inhibited entry of 3-kDa rhodamine-conjugated dextran in the mitochondrial intermembrane space of digitonin-permeabilized hepatocytes, indicative of VDAC closure. In conclusion, AcAld, derived from ethanol metabolism, suppresses ureagenesis in hepatocytes mediated by closure of VDAC.
Several microRNAs (miRNAs) are associated with the molecular pathogenesis of hepatocellular carcinoma (HCC). However, previous studies analyzing the dysregulation of miRNAs in HCC show heterogeneous results. We hypothesized that part of this heterogeneity might be attributable to variations of miRNA expression deriving from the HCC capsule or the fibrotic septa within the peritumoral tissue used as controls. Tissue from surgically resected hepatitis C–associated HCC from six well-matched patients was microdissected using laser microdissection and pressure catapulting technique. Four distinct histologic compartments were isolated: tumor parenchyma (TP), fibrous capsule of the tumor (TC), tumor-adjacent liver parenchyma (LP), and cirrhotic septa of the tumor-adjacent liver (LC). MiRNA expression profiling analysis of 1105 mature miRNAs and precursors was performed using miRNA microarray. Principal component analysis and consecutive pairwise supervised comparisons demonstrated distinct patterns of expressed miRNAs not only for TP versus LP (e.g., intratumoral down-regulation of miR-214, miR-199a, miR-146a, and miR-125a; P< .05) but also for TC versus LC (including down-regulation within TC of miR-126, miR-99a/100, miR-26a, and miR-125b; P< .05). The tumor capsule therefore demonstrates a tumor-like phenotype with down-regulation of well-known tumor-suppressive miRNAs. Variations of co-analyzed fibrotic tissue within the tumor or in controls may have profound influence on miRNA expression analyses in HCC. Several miRNAs, which are proposed to be HCC specific, may indeed be rather associated to the tumor capsule. As miRNAs evolve to be important biomarkers in liver tumors, the presented data have important translational implications on diagnostics and treatment in patients with HCC.
Searching for new strategies to trigger apoptosis in rhabdomyosarcoma (RMS), we investigated the effect of two novel classes of apoptosis-targeting agents, i.e. monoclonal antibodies against TNF-related apoptosis-inducing ligand (TRAIL) receptor 1 (mapatumumab) and TRAIL receptor 2 (lexatumumab) and small-molecule inhibitors of inhibitor of apoptosis (IAP) proteins. Here, we report that IAP inhibitors synergized with lexatumumab, but not with mapatumumab, to reduce cell viability and to induce apoptosis in several RMS cell lines in a highly synergistic manner (combination index <0.1). Cotreatment-induced apoptosis was accompanied by enhanced activation of caspase-8, -9, and -3; loss of mitochondrial membrane potential; and caspase-dependent apoptosis. In addition, IAP inhibitor and lexatumumab cooperated to stimulate the assembly of a cytosolic complex containing RIP1, FADD, and caspase-8. Importantly, knockdown of RIP1 by RNA interference prevented the formation of the RIP1·FADD·caspase-8 complex and inhibited subsequent activation of caspase-8, -9, and -3; loss of mitochondrial membrane potential; and apoptosis upon treatment with IAP inhibitor and lexatumumab. In addition, RIP1 silencing rescued clonogenic survival of cells treated with the combination of lexatumumab and IAP inhibitor, thus underscoring the critical role of RIP1 in cotreatment-induced apoptosis. By comparison, the TNFα-blocking antibody Enbrel had no effect on IAP inhibitor/lexatumumab-induced apoptosis, indicating that an autocrine TNFα loop is dispensable. By demonstrating that IAP inhibitors and lexatumumab synergistically trigger apoptosis in a RIP1-dependent but TNFα-independent manner in RMS cells, our findings substantially advance our understanding of IAP inhibitor-mediated regulation of TRAIL-induced cell death.
Macrophages respond to the Th2 cytokine IL-4 with elevated expression of arachidonate 15-lipoxygenase (ALOX15). Although IL-4 signaling elicits anti-inflammatory responses, 15-lipoxygenase may either support or inhibit inflammatory processes in a context-dependent manner. AMP-activated protein kinase (AMPK) is a metabolic sensor/regulator that supports an anti-inflammatory macrophage phenotype. How AMPK activation is linked to IL-4-elicited gene signatures remains unexplored. Using primary human macrophages stimulated with IL-4, we observed elevated ALOX15 mRNA and protein expression, which was attenuated by AMPK activation. AMPK activators, e.g. phenformin and aminoimidazole-4-carboxamide 1-β-d-ribofuranoside inhibited IL-4-evoked activation of STAT3 while leaving activation of STAT6 and induction of typical IL-4-responsive genes intact. In addition, phenformin prevented IL-4-induced association of STAT6 and Lys-9 acetylation of histone H3 at the ALOX15 promoter. Activating AMPK abolished cellular production of 15-lipoxygenase arachidonic acid metabolites in IL-4-stimulated macrophages, which was mimicked by ALOX15 knockdown. Finally, pretreatment of macrophages with IL-4 for 48 h increased the mRNA expression of the proinflammatory cytokines IL-6, IL-12, CXCL9, and CXCL10 induced by subsequent stimulation with lipopolysaccharide. This response was attenuated by inhibition of ALOX15 or activation of AMPK during incubation with IL-4. In conclusion, limiting ALOX15 expression by AMPK may promote an anti-inflammatory phenotype of IL-4-stimulated human macrophages.
The Na+-F1F0-ATPase operon ofAcetobacterium woodii was recently shown to contain, among eleven atp genes, those genes that encode subunita and b, a gene encoding a 16-kDa proteolipid (subunit c 1), and two genes encoding 8-kDa proteolipids (subunits c 2 andc 3). Because subunits a,b, and c 1 were not found in previous enzyme preparations, we re-determined the subunit composition of the enzyme. The genes were overproduced, and specific antibodies were raised. Western blots revealed that subunits a,b, and c 1 are produced and localized in the cytoplasmic membrane. Membrane protein complexes were solubilized by dodecylmaltoside and separated by blue native-polyacrylamide gel electrophoresis, and the ATPase subunits were resolved by SDS-polyacrylamide gel electrophoresis. N-terminal sequence analyses revealed the presence of subunitsa, c 2, c 3,b, δ, α, γ, β, and ε. Biochemical and immunological analyses revealed that subunitsc 1, c 2, andc 3 are all part of the c-oligomer, the first of a F1F0-ATPase that contains 8- and 16-kDa proteolipids.
Mechanical stress is known to modulate fundamental events such as cell life and death. Mechanical stretch in particular has been identified as a positive regulator of proliferation in skin keratinocytes and other cell systems. In the present study it was investigated whether antiapoptotic signaling is also stimulated by mechanical stretch. It was demonstrated that mechanical stretch rapidly induced the phosphorylation of the proto-oncogene protein kinase B (PKB)/Akt at both phosphorylation sites (serine 473/threonine 308) in different epithelial cells (HaCaT, A-431, and human embryonic kidney-293). Blocking of phosphoinositide 3-OH kinase by selective inhibitors (LY-294002 and wortmannin) abrogated the stretch-induced PKB/Akt phosphorylation. Furthermore mechanical stretch stimulated phosphorylation of epidermal growth factor receptor (EGFR) and the formation of EGFR membrane clusters. Functional blocking of EGFR phosphorylation by either selective inhibitors (AG1478 and PD168393) or dominant-negative expression suppressed stretch-induced PKB/Akt phosphorylation. Finally, the angiotensin II type 1 receptor (AT1-R) was shown to induce positive transactivation of EGFR in response to cell stretch. These findings define a novel signaling pathway of mechanical stretch, namely the activation of PKB/Akt by transactivation of EGFR via angiotensin II type 1 receptor. Evidence is provided that stretch-induced activation of PKB/Akt protects cells against induced apoptosis.