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ObjectiveImprovements to bladder cancer risk stratification guidelines are needed to better tailor post-operative surveillance and adjuvant therapy to individual patients. We previously identified STAG2 as a commonly mutated tumor suppressor gene in bladder cancer and an independent predictor of progression in NMIBC. Here we test the value of combining STAG2 immunostaining with other risk stratification biomarkers in NMIBC, and as an individual biomarker in MIBC.Materials and MethodsSTAG2 immunohistochemistry was performed on a progressor-enriched cohort of tumors from 297 patients with NMIBC, and on tumors from 406 patients with MIBC from Aarhus University Hospital in Denmark. Survival analysis was performed using Kaplan-Meier survival analysis, the log rank test, and Cox proportional hazards models.ResultsSTAG2-negative low-grade NMIBC tumors were 2.5 times less likely to progress to muscle invasion than STAG2-positive low-grade NMIBC tumors (Log-rank test, P = 0.008). In a composite group of patients with AUA intermediate and high-risk NMIBC tumors, STAG2-negative tumors were less likely to progress (Log-rank test, P = 0.02). In contrast to NMIBC, we show that STAG2 is not useful as a prognostic biomarker in MIBC.ConclusionsSTAG2 immunostaining can be used to subdivide low-grade NMIBC tumors into two groups with substantially different risks of disease progression. Furthermore, STAG2 immunostaining may be useful to enhance NMIBC risk stratification guidelines, though larger cohorts are needed to solidify this conclusion in individual risk groups. STAG2 is not useful as a biomarker in MIBC. Further study of the use of STAG2 immunostaining as a biomarker for predicting the clinical behavior in NMIBC is warranted.  相似文献   
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It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.  相似文献   
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PURPOSE: With limited response rates and potential toxicity of chemotherapeutic treatment in patients with recurrent glioma, reliable response assessment is essential. Currently, the assessment of treatment response in glioma patients is based on the combination of radiologic and clinical findings. However, response monitoring with computed tomography (CT) or magnetic resonance imaging (MRI) is hampered by several pitfalls and is prone to interobserver variability. The aim of this study was to establish the value of thallium-201 single-photon emission computed tomography (201Tl-SPECT) as a predictor of overall survival and response to chemotherapy in recurrent glioma, and to compare the value of 201Tl-SPECT with that of CT and MRI. PATIENTS AND METHODS: We studied patients who underwent CT or MRI and 201Tl-SPECT before chemotherapy (n = 57), and patients who also had undergone CT or MRI and 201Tl-SPECT after two courses of chemotherapy (n = 44). The value of the radiologic variables (CT-MRI tumor size, 201Tl-SPECT tumor size, and maximal tumor intensity) at baseline and at follow-up in predicting overall survival, and the percentage of patients alive and progression-free at 6 months (APF6) were examined using Cox regression and logistic regression analysis. RESULTS: Both at baseline and at follow-up, 201Tl-SPECT maximal tumor intensity was the strongest predictive variable and was inversely related to overall survival and APF6. In particular, progression of maximal tumor intensity after two courses of chemotherapy was a powerful predictor of poor outcome. CONCLUSION: 201Tl-SPECT is superior to conventional CT-MRI in the early prediction of overall survival and response to chemotherapy in patients with recurrent glioma.  相似文献   
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In patients with hematological malignancies receiving HLA-matched stem cell transplantation, T cells specific for minor histocompatibility antigens play a major role in graft rejection, induction of graft-versus-host disease and beneficial graft-versus-leukemia reactivity. Several human minor histocompatibility antigens recognized by T cells have been identified, but only two are presented by HLA class II molecules. In search of an efficient approach to identify antigenic peptides processed through the HLA class II pathway, we constructed a cDNA library in bacteria that were induced to express proteins. Bacteria were opsonized with complement to enforce receptor-mediated uptake by Epstein-Barr virus immortalized B cells that were subsequently used as antigen-presenting cells. This approach was validated with an HLA class II-restricted antigen encoded by gene DBY. We were able to identify bacteria expressing DBY diluted into a 300-fold excess of bacteria expressing a nonrelevant gene. Screening of a bacterial library using a DBY-specific CD4 T cell clone resulted in the isolation of several DBY cDNAs. We propose this strategy for a rapid identification of HLA class II-restricted antigenic peptides recognized by CD4 T cells.  相似文献   
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After experiences are encoded, post‐encoding reactivations during sleep have been proposed to mediate long‐term memory consolidation. Spindle–slow oscillation coupling during NREM sleep is a candidate mechanism through which a hippocampal‐cortical dialogue may strengthen a newly formed memory engram. Here, we investigated the role of fast spindle‐ and slow spindle–slow oscillation coupling in the consolidation of spatial memory in humans with a virtual watermaze task involving allocentric and egocentric learning strategies. Furthermore, we analyzed how resting‐state functional connectivity evolved across learning, consolidation, and retrieval of this task using a data‐driven approach. Our results show task‐related connectivity changes in the executive control network, the default mode network, and the hippocampal network at post‐task rest. The hippocampal network could further be divided into two subnetworks of which only one showed modulation by sleep. Decreased functional connectivity in this subnetwork was associated with higher spindle–slow oscillation coupling power, which was also related to better memory performance at test. Overall, this study contributes to a more holistic understanding of the functional resting‐state networks and the mechanisms during sleep associated to spatial memory consolidation.  相似文献   
28.
IntroductionIn the Kell blood group system, the K and k antigens are the clinically most important ones. Maternal anti-K IgG antibodies can lead to the demise of a K-positive fetus in early pregnancy. Intervention can save the fetus. Prenatal K status prediction of the fetus in early pregnancy is desirable and gives a good basis for pregnancy risk management. We present the results from 7 years of clinical experience in predicting fetal K status as well as some theoretical considerations relevant for design of the assay and evaluation of results.MethodsBlood was collected from 43 women, all immunized against K, at a mean gestational age of 18 weeks (range 10–38). A total of 56 consecutive samples were tested. The KEL *01.01 /KEL *02 single nucleotide variant that determines K status was amplified from maternal plasma DNA by PCR without allele specificity. The PCR product was sequenced by NGS technology, and the number of sequenced KEL *01.01 and KEL *02 reads were counted. Prediction of the fetal K status was based on this count and was compared with the serologically determined K status of the newborns.ResultsAll fetal K predictions were in accordance with postnatal serology where available (n = 34), using our current data analysis.ConclusionWe have developed an NGS-based method for the non-invasive prediction of fetal K status. This approach requires special considerations in terms of primer design, stringent preanalytical sample handling, and careful analytical procedures. We analyzed samples starting at GA 10 weeks and demonstrated the correct prediction of fetal K status. This assay enables timely clinical intervention in pregnancies at risk of hemolytic disease of the fetus and newborn caused by maternal anti-K IgG antibodies.  相似文献   
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Bei vielen Organentitäten ist das neoadjuvante Konzept mittlerweile etablierter Bestandteil der Therapie. Die neoadjuvante Therapie scheint auch in speziellen Situationen für Zervixkarzinompatientinnen interessant. Dieser Artikel soll einen Überblick über die aktuell diskutierten Einsatzgebiete in der Neoadjuvanz beim Zervixkarzinom darlegen, die verschiedenen Optionen werden besprochen. Als Grundlage für diesen Artikel dient die S3-Leitlinie Diagnostik, Therapie und Nachsorge der Patientin mit Zervixkarzinom AWMF(Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften)-Registernummer 032/033OL in der Version von 2014. Diese wurde durch die Literatur zur Update-Recherche der Neufassung der Leitlinie erweitert. Die NACT(neoadjuvante Chemotherapie)-Ansprechrate liegt bei 84 %, das progressionsfreie Überleben (PFS) über 5 Jahre und das Gesamtüberleben (OS) betragen 61,9 und 72,8 %. Das Ansprechen auf eine NACT korreliert mit einem besseren Langzeitüberleben. In einer Cochrane-Analyse von 2012 wurde gezeigt, dass eine neoadjuvante Chemotherapie vor geplanter Operation zu einer Verbesserung des PFS (HR [Hazard Ratio] 0,75, 95 %-KI [Konfidenzintervall] 0,61–0,93, p = 0,008) und des Gesamtüberlebens (HR 0,77, 95 %-KI 0,62–0,96, p = 0,02) führt. Unter Berücksichtigung des Random-Effekt-Modells war der Effekt aber nicht mehr signifikant (OR [Odds Ratio] 0,60, 95 %-KI 0,32–1,12, p = 0,11). Bei makroinvasiven Karzinomen in der Schwangerschaft vor einer möglichen Entbindung ist die NACT fester Bestandteil der Therapie. Die Datenlage zum Einsatz der neoadjuvanten Therapie beim Zervixkarzinom ist unklar. Die neoadjuvante Therapie ist aktuell kein Standard in der Behandlung des Zervixkarzinoms. Ungeklärt ist auch die Rolle des operativen Stagings und positiver Lymphknoten nach der neoadjuvanten Therapie. In verschiedenen Metaanalysen konnte gezeigt werden, dass die neoadjuvante Therapie das PFS und das OS verbessert. Dies gilt insbesondere für Frauen, die auf die neoadjuvante Therapie angesprochen haben.  相似文献   
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