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81.
Schmitz Timo Meisinger Christa Kirchberger Inge Thilo Christian Amann Ute Baumeister Sebastian E. Linseisen Jakob 《European journal of epidemiology》2021,36(6):619-627
European Journal of Epidemiology - The aim of this study was to evaluate the impact of the COVID-19 pandemic lockdown on acute myocardial infarction (AMI) care, and to identify underlying stressors... 相似文献
82.
Rainer Amann Carlo Alberto Maggi Sandro Giuliani Josef Donnerer Fred Lembeck 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(6):534-537
Summary In the superfused isolated rat urinary bladder, capsaicin as well as electrical field stimulation evoked the release of calcitonin gene-related peptide-like immunoreactivity (CGRP-IR). Carbonyl cyanide p-trichloromethoxyphenylhydrazone (CCCP, threshold 2 M) reduced both, the capsaicin- and the electrical field stimulation-evoked release of CGRP-IR while a low concentration of Ruthenium Red (RR, 0.6 M and 2 M) selectively attenuated the capsaicin-evoked release of CGRP-IR but did not influence the effect of electrical field stimulation. 20 M RR nearly abolished the capsaicin-evoked release, but also attenuated the effect of electrical field stimulation.In the isolated guinea-pig bronchus, electrical field stimulation and capsaicin induced non-cholinergic contractions which are known to be caused by tachykinin release from afferent nerve terminals. CCCP (0.6 M) only reduced the response to field stimulation; a ten-fold higher concentration of CCCP attenuated field stimulation as well as capsaicin-induced contractions. This is in contrast to the reported selective inhibition of capsaic-ininduced contractions by RR.The present data demonstrate that CCCP generally inhibits evoked neuropeptide release, regardless of the kind of stimulation used while low concentrations of RR preferentially inhibit capsaicin-evoked neuropeptide release.Send offprint requests to: R. Amann at the above address 相似文献
83.
Vu Thuy Khanh Le-Trilling Jana-Fabienne Ebel Franziska Baier Kerstin Wohlgemuth Kai Robin Pfeifer Aart Mookhoek Philippe Krebs Madita Determann Benjamin Katschinski Alexandra Adamczyk Erik Lange Robert Klopfleisch Christian M. Lange Viktoriya Sokolova Mirko Trilling Astrid M. Westendorf 《European journal of immunology》2023,53(2):2249940
Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis. 相似文献
84.
Marcus Knorr Michael Völker Peter Oliver Denk Kerstin Wunderlich Hans-Jürgen Thiel 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(10):667-671
Background: Although platelet-derived growth factor (PDGF) has been thought to be critical in the wound-healing response of Tenon's capsule fibroblasts after glaucoma filtration surgery, no information is currently available concerning the proliferative effect of PDGF isoforms on this cell type. The aim of the present study was to evaluate the proliferative effect of PDGF-AB heterodimer and PDGF-AA and -BB homodimers on cultured human Tenon's capsule fibroblasts. Methods: Human Tenon's capsule fibroblasts, cultured under serum-free conditions, were stimulated with PDGF-AA, -AB and -BB isoforms in concentrations ranging from 1 to 100 ng/ml. Cell numbers were determined on days 1, 3, 5 and 7, using a cell counter. Results: Addition of PDGF-AB and -BB led to a dosedependent increase in cell proliferation. A maximal response (79.9% over control) was obtained after 7 days with 30 ng/ml of PDGF-BB, with an EC50 of 8.9 ng/ml. The maximal increase in cell proliferation caused by PDGF-AB (30 ng/ml) was 54.9%, with an EC50 of 12.5 ng/ml. Stimulation with PDGF-AA revealed a significant effect only with concentrations higher than 30 ng/ml. Conclusion: Our results indicate that PDGF-AB and -BB isoforms are potent stimulators of proliferation of human Tenon's capsule fibroblasts, suggesting that PDGF-AB and -BB isoforms play an important role in the wound-healing response after glaucoma filtration surgery.Presented in part at the annual meeting of the Deutsche Ophthalmologische Gesellschaft, Mannheim, September 1996 相似文献
85.
Lisa Marlene Krassuski Sibylle Kautz-Freimuth Vera Vennedey Kerstin Rhiem Rita K. Schmutzler Stephanie Stock 《Geburtshilfe und Frauenheilkunde》2021,81(6):679
Introduction Women with a pathogenic BRCA1/2 mutation have a markedly increased lifetime risk of developing breast and/or ovarian cancer. The current preventive treatment alternatives that are offered are an intensified breast cancer screening programme and risk-reducing operations. Before deciding on one option, medical and personal factors such as life situation and individual preferences must be weighed carefully. Decision aids are used internationally to support BRCA1/2 mutation carriers during their decision-making process. In this study these are analysed structurally for the first time and their applicability to the German context is examined. Material and Methods A systematic literature search in five electronic databases and a manual search were performed. The identified decision aids were evaluated with regard to formal criteria, medical content and quality. The qualitative assessment used the criteria of the International Patient Decision Aid Standards Collaboration (IPDASi v4.0), which examined various dimensions (e.g., information, probabilities, values). Results Twenty decision aids, which were published between 2003 and 2019 in Australia (n = 4), the United Kingdom (n = 3), Canada (n = 2), the Netherlands (n = 2) and the USA (n = 9), were included. Nine focus on BRCA1/2 mutation carriers and eleven include other risk groups. Eighteen include risk-reducing operations as decision options, 14 list screening methods for breast and/or ovarian cancer, and 13 describe the possibility of pharmacological prevention by means of selective oestrogen receptor modulators or aromatase inhibitors. Nine of the 20 decision aids meet fundamental quality criteria (IPDASi v4.0 qualification criteria). Conclusion International decision aids can serve formally as a basis for a German decision aid for BRCA1/2 mutation carriers. Some of them differ markedly in content from the recommendations of German guidelines. Only a few achieve a high quality. Key words: BRCA1, BRCA2, decision aid, familial breast cancer, familial ovarian cancer 相似文献
86.
The aim of the present study was to investigate whether amperozide, an antipsychotic drug which possesses anti-aggressive and anxiolytic-like properties, stimulates the secretion of oxytocin and if so, by which receptor mechanism. For this purpose, female or male Sprague Dawley rats were given amperozide (0.5, 2.5 and 5.0 mg/kg IP), ritanserin (5.0 mg/kg), raclopride (2.0 mg/kg) and prazosin (1.0 mg/kg) and were subsequently decapitated for collection of blood (30 and 120 min) after injection. Oxytocin levels were measured with radioimmunoassay. Amperozide 2.5 and 5 mg/kg increased plasma levels of oxytocin significantly (P<0.05 and <0.001). The effect appeared maximal about 30 min after injection of the drug and oxytocin levels were almost back to basal within 120 min. Similar effects were obtained in female and male rats as well as in animals that were freely fed or food deprived for 24 h. CSF levels of oxytocin were also increased. Ritanserin, a 5-HT2-receptor antagonist but not the D2 receptor antagonist raclopride or the 1-adrenoceptor antagonist prazosin stimulated oxytocin release. In addition, clozapine, a neuroleptic with potent HT2-antagonistic properties, was a potent releaser of oxytocin, whereas haloperidol was without effect. A possible role for oxytocin in the behavioural effects of amperozide and clozapine remains to be explored. 相似文献
87.
Athanassios Argiris Bruce E Brockstein Daniel J Haraf Kerstin M Stenson Bharat B Mittal Merrill S Kies Fred R Rosen Borko Jovanovic Everett E Vokes 《Clinical cancer research》2004,10(6):1956-1962
PURPOSE: The purpose of this retrospective analysis was to evaluate the emergence of second primary malignancies and the contribution of different causes of death to the outcome of patients with locoregionally advanced head and cancer receiving primary chemoradiotherapy. EXPERIMENTAL DESIGN: We studied 324 patients with stage IV squamous cell head and neck cancer who were enrolled on five consecutive multicenter Phase II studies of concurrent chemoradiotherapy. All of the regimens included concurrent 5-fluorouracil and hydroxyurea on an alternate week schedule with radiotherapy, either alone (FHX) or with cisplatin (C-FHX) or paclitaxel (T-FHX). The cumulative incidence of second primary tumors or death from any cause was estimated using methods of competing risk analysis. RESULTS: Median follow-up of surviving patients was 5.2 years (2-10.6 years). The 5-year overall survival and progression-free survival of the cohort were 46% and 65%, respectively. Causes of death and median time of occurrence were as follows: disease (n = 88; 1.5 years), treatment-associated acute or late complications (n = 30; 4 months), second primary tumors (n = 18; 3.5 years), comorbidities (n = 41; 1.9 years), and unknown (n = 20; 5.1 years). Predominant causes of death from comorbidities were cardiac and respiratory illnesses. Twenty-six patients (8%) developed a second primary tumor at a median time of 2.8 years (4 months to 10 years). The cumulative incidence of second primary tumors was 5%, 7%, and 13% at 3, 5, and 10 years, respectively. The most frequent site of second primaries was the lung (n = 13), followed by the esophagus (n = 3) and head and neck (n = 2) CONCLUSIONS: Patients with locoregionally advanced head and neck cancer treated with concurrent chemoradiotherapy are potentially curable but face significant risks of mortality from causes other than disease progression. Ameliorating toxicity, and implementing secondary screening and chemoprevention strategies are major goals in the management of head and neck cancer. 相似文献
88.
Phase II trial of ZD1839 in recurrent or metastatic squamous cell carcinoma of the head and neck. 总被引:11,自引:0,他引:11
Ezra E W Cohen Fred Rosen Walter M Stadler Wendy Recant Kerstin Stenson Dezheng Huo Everett E Vokes 《Journal of clinical oncology》2003,21(10):1980-1987
PURPOSE: The epidermal growth factor receptor (EGFR) is a mediator of squamous cell carcinoma of the head and neck (SCCHN) development. ZD1839 is an orally active, selective EGFR tyrosine kinase inhibitor. This phase II study sought to explore the activity, toxicity, and pharmacodynamics of ZD1839 in SCCHN. PATIENTS AND METHODS: Patients with recurrent or metastatic SCCHN were enrolled through the University of Chicago Phase II Consortium. Patients were allowed no more than one prior therapy for recurrent or metastatic disease and were treated with single-agent ZD1839 500 mg/d. Patient tumor biopsies were obtained and stained immunohistochemically for EGFR, extracellular signal-regulated kinase 1 (ERK1), and phosphorylated ERK1 (p-ERK). Study end points included response rate, time to progression, median survival, and inhibition of p-ERK. RESULTS: Fifty-two patients were enrolled (40 male and 12 female) with a median age of 59 years (range, 34 to 84 years). Fourteen patients received ZD1839 through a feeding tube. Half the cohort received ZD1839 as second-line therapy. Forty-seven patients were assessable for response, with an observed response rate of 10.6% and a disease control rate of 53%. Median time to progression and survival were 3.4 and 8.1 months, respectively. The only grade 3 toxicity encountered was diarrhea in three patients. Performance status and development of skin toxicity were found to be strong predictors of response, progression, and survival. Ten biopsy samples were assessable and revealed no significant change in EGFR or p-ERK expression with ZD1839 therapy. CONCLUSION: ZD1839 has single-agent activity and is well tolerated in refractory SCCHN. In contrast to other reports, development of skin toxicity was a statistically significant predictor of response and improved outcome. 相似文献
89.
Everett E Vokes Kerstin Stenson Fred R Rosen Merrill S Kies Alfred W Rademaker Mary Ellyn Witt Bruce E Brockstein Marcy A List Bing Bing Fung Louis Portugal Bharat B Mittal Harold Pelzer Ralph R Weichselbaum Daniel J Haraf 《Journal of clinical oncology》2003,21(2):320-326
PURPOSE: The paclitaxel, fluorouracil, and hydroxyurea regimen of paclitaxel, infusional fluorouracil, hydroxyurea, and twice-daily radiation therapy (TFHX) administered every other week has resulted in 3-year survival rates of 60% of stage IV patients. Locoregional and distant failure rates were 13% and 23%, respectively. To reduce distant failure rates, we added a brief course of induction chemotherapy to TFHX. PATIENTS AND METHODS: Sixty-nine patients received six weekly doses of carboplatin (AUC2) and paclitaxel (135 mg/m2) followed by five cycles of TFHX. RESULTS: Ninety-six percent had stage IV disease. Response to induction chemotherapy was partial response 52% and complete response (CR) 35%. Symptomatically, there was a significant reduction in mouth and throat pain. The most common grade 3 or 4 toxicity was neutropenia (36%). Best response following completion of TFHX was CR in 83%. Toxicities of TFHX consisted of grade 3 or 4 mucositis (74% and 2%) and dermatitis (47% and 14%). At a median follow-up of 28 months, locoregional or systemic disease progression were each noted in five patients. The overall 3-year progression-free survival was 80% (95% confidence interval [CI], 71% to 90%), and the 2- and 3-year overall survival rates were 77% (95% CI, 66% to 87%) and 70% (95% CI, 59% to 82%), respectively. At 12 months, five patients were completely feeding-tube dependent. CONCLUSION: Administration of carboplatin and paclitaxel before TFHX chemoradiotherapy results in high response activity and may decrease distant failure rates. Overall survival, progression, and organ preservation/functional outcome data support definitive evaluation of this approach. 相似文献