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Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is an uncommon disorder of unknown etiology affecting the retina, the retinal pigment epithelium, and the choroid. Although several etiological factors have been suggested, none has been confirmed. We report a case of APMPPE associated with acute infection of Borreliosis. A 30-year-old man presented with a decrease in vision in the right eye of about 1-week duration. His visual acuity in the right eye was 6/36. Fundus exam revealed the presence of multiple placoid creamy retinal/subretinal lesions in the right eye. Fundus fluorescein angiography supported the diagnosis of APMPPE. Blood tests revealed the presence of concomitant acute Borreliosis infection, as confirmed by IgM. The patient received oral prednisone therapy and amoxicillin. Six weeks later, the visual acuity returned to 6/6, and the patient was symptom free. Borreliosis can have several manifestations in the eye. One of the less common presentations is an APMPPE-like picture. The clinician should suspect acute Borreliosis infection in patients presenting with APMPPE, especially when there is a history of a tick bite, when the patient has systemic symptoms, or when living in/visiting endemic areas. This may help in the prompt management of APMPPE, avoiding complications due to the condition itself, or systemic involvement secondary to the Borreliosis infection.
Background: Computed tomography (CT) low-dose (LD) imaging is used to lower radiation exposure, especially in vascular imaging; in current literature, this is mostly on latest generation high-end CT systems.
Purpose: To evaluate the effects of reduced tube current on objective and subjective image quality of a 15-year-old 16-slice CT system for pulmonary angiography (CTPA).
Material and Methods: CTPA scans from 60 prospectively randomized patients (28 men, 32 women) were examined in this study on a 15-year-old 16-slice CT scanner system. Standard CT (SD) settings were 100 kV and 150 mAs, LD settings were 100 kV and 50 mAs. Attenuation of the pulmonary trunk, various anatomic landmarks, and image noise were quantitatively measured; contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR) were calculated. Three independent blinded radiologists subjectively rated each image series using a 5-point grading scale.
Results: CT dose index (CTDI) in the LD series was 66.46% lower compared to the SD settings (2.49 ± 0.55 mGy versus 7.42 ± 1.17 mGy). Attenuation of the pulmonary trunk showed similar results for both series (SD 409.55 ± 91.04 HU; LD 380.43 HU ± 93.11 HU; P = 0.768). Subjective image analysis showed no significant differences between SD and LD settings regarding the suitability for detection of central and peripheral PE (central SD/LD, 4.88; intra-class correlation coefficients [ICC], 0.894/4.83; ICC, 0.745; peripheral SD/LD, 4.70; ICC, 0.943/4.57; ICC, 0.919; all P > 0.4).
Conclusion: The LD protocol, on a 15-year-old CT scanner system without current high-end hardware or post-processing tools, led to a dose reduction of approximately 67% with similar subjective image quality and delineation of central and peripheral pulmonary arteries.
BACKGROUND: Evaluation of latest generation automated attenuation-based tube potential selection (ATPS) impact on image quality and radiation dose in contrast-enhanced chest-abdomen-pelvis computed tomography examinations for gynaecologic cancer staging.
METHODS: This IRB approved single-centre, observer-blinded retrospective study with a waiver for informed consent included a total of 100 patients with contrast-enhanced chest-abdomen-pelvis CT for gynaecologic cancer staging. All patients were examined with activated ATPS for adaption of tube voltage to body habitus. 50 patients were scanned on a third-generation dual-source CT (DSCT), and another 50 patients on a second-generation DSCT. Predefined image quality setting remained stable between both groups at 120 kV and a current of 210 Reference mAs. Subjective image quality assessment was performed by two blinded readers independently. Attenuation and image noise were measured in several anatomic structures. Signal-to-noise ratio (SNR) was calculated. For the evaluation of radiation exposure, CT dose index (CTDIvol) values were compared.
RESULTS: Diagnostic image quality was obtained in all patients. The median CTDIvol (6.1 mGy, range 3.9-22 mGy) was 40 % lower when using the algorithm compared with the previous ATCM protocol (median 10.2 mGy · cm, range 5.8-22.8 mGy). A reduction in potential to 90 kV occurred in 19 cases, a reduction to 100 kV in 23 patients and a reduction to 110 kV in 3 patients of our experimental cohort. These patients received significantly lower radiation exposure compared to the former used protocol.
CONCLUSION: Latest generation automated ATPS on third-generation DSCT provides good diagnostic image quality in chest-abdomen-pelvis CT while average radiation dose is reduced by 40 % compared to former ATPS protocol on second-generation DSCT.
Purpose: To determine the value of the 2D multiple-echo data image combination (MEDIC) sequence relative to the short-tau inversion recovery (STIR) sequence regarding the depiction of chondral lesions in the patellofemoral joint.
Materials and methods: During a period of 6 month patients with acute pain at the anterior aspect of the knee, joint effusion and suspected chondral lesion defect in the patellofemoral joint underwent MRI including axial MEDIC and STIR imaging. Patients with chondral lesions in the patellofemoral joint on at least one sequence were included. The MEDIC and STIR sequence were quantitatively compared regarding the patella cartilage-to-effusion contrast-to-noise ratio (CNR) and qualitatively regarding the depiction of chondral lesions independently scored by two radiologists on a 3-point scale (1 = not depicted; 2 = blurred depicted; 3 = clearly depicted) using the Wilcoxon-Mann-Whitney-Test. For the analysis of inter-observer agreement the Cohen's Weighted Kappa test was used.
Results: 30 of 58 patients (male: female, 21:9; age: 44 ± 12 yrs) revealed cartilage lesions (fissures, n = 5 including fibrillation; gaps, n = 15; delamination, n = 7; osteoarthritis, n = 3) and were included in this study. The STIR-sequence was significantly (p < 0.001) superior to the MEDIC-sequence regarding both, the patella cartilage-to-effusion CNR (mean CNR: 232 ± 61 vs. 40 ± 16) as well as the depiction of chondral lesion (mean score: 2.83 ± 0.4 vs. 1.75 ± 0.7) with substantial inter-observer agreement in the rating of both sequences (κ = 0.76–0.89).
Conclusion: For the depiction of chondral lesions in the patellofemoral joint, the axial STIR-sequence should be chosen in preference to the axial MEDIC-sequence.
Evidence about distribution patterns of brain metastases with regard to breast cancer subtypes and its influence on the prognosis of patients is insufficient. Clinical data, cranial computed tomography (CT) and magnetic resonance imaging (MRI) scans of 300 breast cancer patients with brain metastases (BMs) were collected retrospectively in four centers participating in the Brain Metastases in Breast Cancer Registry (BMBC) in Germany. Patients with positive estrogen (ER), progesterone (PR), or human epidermal growth factor receptor 2 (HER2) statuses, had a significantly lower number of BMs at diagnosis. Concerning the treatment mode, HER2-positive patients treated with trastuzumab before the diagnosis of BMs showed a lower number of intracranial metastases (p < 0.001). Patients with a HER2-positive tumor-subtype developed cerebellar metastases more often compared with HER2-negative patients (59.8% vs. 44.5%, p = 0.021), whereas patients with triple-negative primary tumors had leptomeningeal disease more often (31.4% vs. 18.3%, p = 0.038). The localization of Brain metastases (BMs) was associated with prognosis: patients with leptomeningeal disease had shorter survival compared with patients without signs of leptomeningeal disease (median survival 3 vs. 5 months, p = 0.025). A shorter survival could also be observed in the patients with metastases in the occipital lobe (median survival 3 vs. 5 months, p = 0.012). Our findings suggest a different tumor cell homing to different brain regions depending on subtype and treatment. View Full-Text
Bewegung und sportliche Aktivität fördern die Gesundheit des Organismus und senken das Risiko chronischer Krankheiten. Sie bewirken dabei eine Vielzahl von physiologischen und biochemischen Veränderungen in der Skelettmuskulatur, insbesondere Muskelfasertyp-Transformation, Änderungen des Muskelmetabolismus und der Angiogenese. Unter basalen Bedingungen spielen reactive oxygen species (ROS) eine essentielle Rolle für die normale Muskelfunktion. Die Sport-induzierte Produktion von ROS erweist sich als wichtige physiologische Funktion für die Regulierung der Muskelkraft und der Anpassungsreaktion der Muskelfasern auf das Training. Eine der wichtigsten Quellen von ROS im kardiovaskulären System sowie in der Skelettmuskulatur ist die Familie der NADPH-Oxidasen (Nox). Im Unterschied zu anderen NADPHOxidasen ist Nox4 konstitutiv aktiv und produziert Wasserstoffperoxid (H2O2), welches in diversen zellulären Signalkaskaden involviert ist. Gleichzeitig gibt es zahlreiche Hinweise, dass Nox4 über die ROS-Produktion an Sport-induzierten Anpassungsprozessen in Skelettmuskeln beteiligt ist. Vor diesem Hintergrund wurde die Hypothese aufgestellt, dass Nox4 die Sport-induzierte Transformation von langsam- zu schnellkontrahierenden Muskelfasern, die Änderungen des Muskelstoffwechsels sowie die Sport-induzierte und die retinale Angiogenese beeinflusst. Die Untersuchung der Sportinduzierten Fasertyptransformation zeigte, dass die relative Zusammensetzung der Muskelfasern in Nox4-Knockout- und Wildtyp-Mäusen sehr ähnlich und somit von Nox4 unabhängig war. Obwohl das Training die Expression von PGC1α und GLUT4 sowie die AMPK-Aktivierung steigerte, hatte Nox4 nur eine geringe, nicht konstitutive Auswirkung auf den Muskelmetabolismus. Außerdem zeigte die vorliegende Studie, dass Nox4 die Sport-induzierte Angiogenese fördert. Nox4 führte zu einer erhöhten Stretch- und Hypoxie-induzierten Expression von VEGF in Myoblasten, die aus C2C12-Zellen und Satellitenzellen differenziert wurden. Als Folge des Nox4-Knockouts wurde nicht nur eine Reduktion der VEGF-Expression, sondern auch eine Steigerung der Expression von Angiopoietin 1 (Ang1) nachgewiesen, welches die Sport-induzierte Angiogenese hemmte. Das Fehlen von Nox4 schützte außerdem vor der retinalen Neoangiogenese und trug zu einer schnelleren Heilung nach der Oxygen-inducedretinopathy (OIR) bei, indem das Netzwerk neuer Gefäße mittels Ang1 stabilisiert wurde. Somit führt Nox4 zur Sport- und Hypoxie-induzierten Angiogenese durch einen Doppelmechanismus der Induktion und Aufrechterhaltung der VEGF Expression und der Hemmung von Ang1.
Combined diabetes-obesity syndromes severely impair regeneration of acute skin wounds in mouse models. This study assessed the contribution of subcutaneous adipose tissue to exacerbated wound inflammatory conditions. Genetically obese (ob/ob) mice showed an increased expression of positive transcriptional effectors of adipocyte differentiation such as Krüppel-like factor (KLF)-5 and peroxisome proliferator-activated receptor (PPAR)-γ and an associated expression of leptin and fatty acid-binding protein (FABP)-4, but also CXCL2 in isolated subcutaneous fat. This observation in obese mice is in keeping with differentially elevated levels of KLF-5, PPAR-γ, leptin, FABP-4 and CXCL2 in in vitro-differentiated 3T3-L1 adipocytes. Notably, CXCL2 expression restrictively appeared upon cytokine (IL-1β/TNF-α) stimulation only in mature, but not immature 3T3-L1 adipocytes. Of importance, the critical regulator of adipocyte maturation, PPAR-γ, was merely expressed in the final phase of in-vitro induced adipocyte differentiation from 3T3-L1 pre-adipocytes. Consistently, the PPAR-γ agonist rosiglitazone suppressed cytokine-induced CXCL2 release from mature adipocytes, but not from early 3T3-L1 adipocyte stages. The inhibitory effect of PPAR-γ activation on CXCL2 release appeared to be a general anti-inflammatory effect in mature adipocytes, as cytokine-induced cyclooxygenase (Cox)-2 was simultaneously repressed by rosiglitazone. In accordance with these findings, oral administration of rosiglitazone to wounded obese mice significantly changed subcutaneous adipocyte morphology, reduced wound CXCL2 and Cox-2 expression and improved tissue regeneration. Thus, our data suggest that PPAR-γ might provide a target to suppress inflammatory signals from mature adipocytes, which add to the prolonged wound inflammation observed in diabetes-obesity conditions.
Neurological diseases associated with neuronal death are also accompanied by axonal denervation of connected brain regions. In these areas, denervation leads to a decrease in afferent drive, which may in turn trigger active central nervous system (CNS) circuitry rearrangement. This rewiring process is important therapeutically, since it can partially recover functions and can be further enhanced using modern rehabilitation strategies. Nevertheless, the cellular mechanisms of brain rewiring are not fully understood. We recently reported a mechanism by which neurons remodel their local connectivity under conditions of network-perturbance: hippocampal pyramidal cells can extend spine head protrusions (SHPs), which reach out toward neighboring terminals and form new synapses. Since this form of activity-dependent rewiring is observed only on some spines, we investigated the required conditions. We speculated, that the actin-associated protein synaptopodin, which is involved in several synaptic plasticity mechanisms, could play a role in the formation and/or stabilization of SHPs. Using hippocampal slice cultures, we found that ~70 % of spines with protrusions in CA1 pyramidal neurons contained synaptopodin. Analysis of synaptopodin-deficient neurons revealed that synaptopodin is required for the stability but not the formation of SHPs. The effects of synaptopodin could be linked to its role in Ca(2+) homeostasis, since spines with protrusions often contained ryanodine receptors and synaptopodin. Furthermore, disrupting Ca(2+) signaling shortened protrusion lifetime. By transgenically reintroducing synaptopodin on a synaptopodin-deficient background, SHP stability could be rescued. Overall, we show that synaptopodin increases the stability of SHPs, and could potentially modulate the rewiring of microcircuitries by making synaptic reorganization more efficient.
B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is an aggressive hematologic malignancy of bone-marrow (BM)-derived lymphoid precursor cells at various stages of differentiation. Although first-line therapy with chemotherapy and—in the case of BCR-ABL1 positive ALL—tyrosine kinase inhibitors is initially highly effective with remission rates of >90%, the overall survival rate in adult patients is 40–50% across all risk groups. Relapse originates from putative leukemia-initiating cells (LICs) that are intrinsically resistant to chemotherapeutic regimens, which may explain the poor long-term prognosis of patients with disease recurrence. Eradication of LICs thus is a principal aim of novel therapeutic approaches. A prerequisite for developing effective LIC-targeted treatments is the ability to identify and clinically monitor LICs in ALL, a goal that has to date been elusive. The existence, phenotype, biological properties and the hierarchical organization of LICs in BCP-ALL remain highly controversial. ...
Background: Lectures remain an important teaching method to present and structure knowledge to many students concurrently. Adequate measures are necessary to maintain the quality of the lectures. The aim of this study was to determine the impact on the lecture quality using written structured feedback and to compare the ratings of surgical lectures between students and surgical peers.
Methods: Prospective analysis of two consecutive surgical lecture series for undergraduate students at Goethe-University Medical School was performed before and after evaluation of the lecturers via independent written feedback from trained undergraduate students and surgeons. The 22-item feedback instrument covered three areas of performance: content, visualization, and delivery. Additional suggestions for improvement were provided from
both students and surgical peers who anonymously attended the lectures. The lecturers, experienced surgeons, as well as the student and peer raters were blinded in terms of the aim and content of the study. Their response to the feedback was collected using a web-based 13-item questionnaire. The Kendall’s-W coefficient was computed to calculate inter-rater reliability (IRR). Differences between ratings before and after feedback were analyzed using Student’s t-test for dependent samples. The Kolmogorov-Smirnov-test was used for independent samples.
Results: A total of 22 lectures from a possible 32 given by 13 lecturers were included and analyzed by at least three surgeons and two students. There were significant improvements in overall score as well as in the details of 9 of the 13 items were found. The average inter-rater reliability was 0.71. There were no differences in the ratings as a function of the rater’s level of expertise (peers vs. students). We found that 13/23 lecturers (56.5%) answered the questionnaire, and 92% strongly agreed that the written feedback was useful. 76.9% of the lecturers revised their lecture based on the written feedback requiring on average 112.5 min (range from 20 to 300 min).
Conclusions: Overall, this study indicates that structured written feedback provided by trained peers and students that is subsequently discussed by the lecturers concerned is a highly effective and efficient method to improve aspects of lecturing. We anticipate that structured written feedback by trained students that is discussed by the lecturers concerned will improve lecturing.
Keywords: Lecture, Feedback, Surgery, Peer-feedback, Evaluation, Undergraduate training