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1.
Single amino acid substitutions in melanoma-associated peptides dramatically enhance T-cell cytotoxicity against target cells presenting the modified peptides (often referred to as heteroclitic peptides). The authors tried to determine whether peptide modifications influence other aspects of T-cell immunity toward malignant melanoma. A heteroclitic peptide, E26F, with an E to F substitution in melanoma antigen recognized by T cell 1 (MART-1)26-35, triggers an enhanced tyrosine phosphorylation response when compared with the native- and other-modified MART-1 peptides. Similarly, the E26F peptide enhances the production of mRNA for interleukin (IL)-5, IL-10, IL-13, IL-15, and interferon-gamma and significantly enhances release of IL-13 and IL-10 from anti-MART-1 cytotoxic T cells. Another heteroclitic peptide, 1L, with an A to L substitution in MART-1(27-35), also enhances the tyrosine phosphorylation response in anti-MART-1 cytotoxic CD8+ T cells. Yet, 1L does not enhance the production of T helper cell type 2-like cytokines (IL-10 and IL-13). Together these data show that minor amino acid modifications of immunodominant melanoma peptides profoundly influence the cytokine response in melanoma-specific T cells.  相似文献   
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Lymphotoxin α (LTα) plays a key role in the formation of lymphatic vasculature and secondary lymphoid structures. Cutaneous T cell lymphoma (CTCL) is the most common primary lymphoma of the skin and in advanced stages, malignant T cells spreads through the lymphatic to regional lymph nodes to internal organs and blood. Yet, little is known about the mechanism of the CTCL dissemination. Here, we show that CTCL cells express LTα in situ and that LTα expression is driven by aberrantly activated JAK3/STAT5 pathway. Importantly, via TNF receptor 2, LTα functions as an autocrine factor by stimulating expression of IL-6 in the malignant cells. LTα and IL-6, together with VEGF promote angiogenesis by inducing endothelial cell sprouting and tube formation. Thus, we propose that LTα plays a role in malignant angiogenesis and disease progression in CTCL and may serve as a therapeutic target in this disease.  相似文献   
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Background: Alongside metabolic diseases (esp. obesity), allergic disorders are becoming increasingly prevalent. Since both obesity and allergies are highly impacted by environmental determinants, with this study we assessed the potential link between metabolic implications and two distinct types of allergies. Methods: Using cross-sectional data from the German FoCus cohort, n = 385 allergy cases, either hay fever (=type I allergy, n = 183) or contact allergy (=type IV allergy, n = 202) were compared to age- and sex-matched healthy control subjects (1:1 ratio, in total n = 770) regarding their metabolic phenotype, diet, physical activity, sleep, gut microbial composition, and serum metabolite profile using suitable BMI-adjusted models. Results: Obesity and metabolic alterations were found significantly more prevalent in subjects with allergies. In fact, this relation was more pronounced in contact allergy than hay fever. Subsequent BMI-adjusted analysis reveals particular importance of co-occurring hyperlipidaemia for both allergy types. For contact allergy, we revealed a strong association to the dietary intake of poly-unsaturated fatty acids, particularly α-linolenic acid, as well as the enrichment of the corresponding metabolic pathway. For hay fever, there were no major associations to the diet but to a lower physical activity level, shorter duration of sleep, and an altered gut microbial composition. Finally, genetic predisposition for hyperlipidaemia was associated to both contact allergy and hay fever. Conclusions: Reflected by higher allergy prevalence, our findings indicate an impaired immune response in obesity and hyperlipidaemia, which is differentially regulated in type I and type IV allergies by an unfavourable lifestyle constellation and subsequent microbial and metabolic dysfunctions.  相似文献   
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Guinea pig tectorial membrane profile in an in vitro cochlear preparation   总被引:2,自引:0,他引:2  
The guinea pig cochlea was examined under high-magnification light microscopy in an in vitro preparation. After extraction of the otic capsule, the bulla was opened widely and a small hole made into the fourth turn of the scala vestibuli. The organ of Corti was visualized under artificial endolymph at 600 X magnification. Added 1-micron titanium dioxide particles settled on the upper surface of the transparent tectorial membrane. Particle positions showed that much of this upper surface lay in a flat sheet that extended centrifugally almost to the Hensen's cells, giving the impression it was attached there. The sheet extended at least to the level of the inner hair cells, where a tectorial membrane thickness of about 40 micron was reached. Titanium dioxide particles were seen regularly in immediate proximity to the hair cell cilia, indicating that scala media is continuous with the subtectorial space. Upon mechanical manipulation, Hensen's cells proved to be extremely cohesive and elastic. It is suggested that hair cell stereocilia provide major mechanical connections for the tectorial membrane.  相似文献   
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BackgroundCardiovascular risk factors and comorbidities are highly prevalent among COVID‐19 patients and are associated with worse outcomes.HypothesisWe therefore investigated if established cardiovascular risk assessment models could efficiently predict adverse outcomes in COVID‐19. Furthermore, we aimed to generate novel risk scores including various cardiovascular parameters for prediction of short‐ and midterm outcomes in COVID‐19.MethodsWe included 441 consecutive patients diagnosed with SARS‐CoV‐2 infection. Patients were followed‐up for 30 days after the hospital admission for all‐cause mortality (ACM), venous/arterial thromboembolism, and mechanical ventilation. We further followed up the patients for post‐COVID‐19 syndrome for 6 months and occurrence of myocarditis, heart failure, acute coronary syndrome (ACS), and rhythm events in a 12‐month follow‐up. Discrimination performance of DAPT, GRACE 2.0, PARIS‐CTE, PREDICT‐STABLE, CHA2‐DS2‐VASc, HAS‐BLED, PARIS‐MB, PRECISE‐DAPT scores for selected endpoints was evaluated by ROC‐analysis.ResultsOut of established risk assessment models, GRACE 2.0 score performed best in predicting combined endpoint and ACM. Risk assessment models including age, cardiovascular risk factors, echocardiographic parameters, and biomarkers, were generated and could successfully predict the combined endpoint, ACM, venous/arterial thromboembolism, need for mechanical ventilation, myocarditis, ACS, heart failure, and rhythm events. Prediction of post‐COVID‐19 syndrome was poor.ConclusionRisk assessment models including age, laboratory parameters, cardiovascular risk factors, and echocardiographic parameters showed good discrimination performance for adverse short‐ and midterm outcomes in COVID‐19 and outweighed discrimination performance of established cardiovascular risk assessment models.  相似文献   
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BACKGROUND: Ovarian cancer is a major cause of cancer deaths in women and usually presents with diffuse abdominal disease. Lymph node metastases are common, but axillary lymph nodes are rarely involved. CASE: A 63-year-old woman, initially presenting with abdominal symptoms and massive ascites, underwent optimal cytoreduction followed by intravenous chemotherapy with paclitaxel and carboplatin. The patient subsequently underwent a second-look surgery revealing only microscopically positive disease and then received intraperitoneal chemotherapy with cisplatin. At a follow-up visit, she was found to have bilateral axillary lymph node enlargement. Mammography revealed no lesions in either breast. Fine needle aspiration dissection confirmed the diagnosis of metastatic, recurrent ovarian adenocarcinoma and subsequently axillary lymph node dissection was undertaken. CONCLUSION: Ovarian carcinoma, which usually follows typical patterns of metastatic involvement, can appear in unusual areas.  相似文献   
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