7 results on '"Schmidt WE"'
Search Results
2. Sex-specific cardiovascular remodeling leads to a divergent sex-dependent development of heart failure in aged hypertensive rats.
- Author
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Kovács Á, Zhazykbayeva S, Herwig M, Fülöp GÁ, Csípő T, Oláh N, Hassoun R, Budde H, Osman H, Kaçmaz M, Jaquet K, Priksz D, Juhász B, Akin I, Papp Z, Schmidt WE, Mügge A, El-Battrawy I, Tóth A, and Hamdani N
- Subjects
- Animals, Male, Female, Rats, Sex Factors, Connectin metabolism, Disease Models, Animal, Calcium-Calmodulin-Dependent Protein Kinase Type 2 metabolism, Echocardiography, Phosphorylation, Muscle, Smooth, Vascular metabolism, Muscle, Smooth, Vascular physiopathology, Heart Failure physiopathology, Heart Failure metabolism, Hypertension metabolism, Hypertension physiopathology, Rats, Transgenic, Ventricular Remodeling physiology, Myocytes, Cardiac metabolism
- Abstract
Introduction: The prevalence of heart failure with preserved ejection fraction (HFpEF) is continuously rising and predominantly affects older women often hypertensive and/or obese or diabetic. Indeed, there is evidence on sex differences in the development of HF. Hence, we studied cardiovascular performance dependent on sex and age as well as pathomechanisms on a cellular and molecular level., Methods: We studied 15-week- and 1-year-old female and male hypertensive transgenic rats carrying the mouse Ren-2 renin gene (TG) and compared them to wild-type (WT) controls at the same age. We tracked blood pressure and cardiac function via echocardiography. After sacrificing the 1-year survivors we studied vascular smooth muscle and endothelial function. Isolated single skinned cardiomyocytes were used to determine passive stiffness and Ca
2+ -dependent force. In addition, Western blots were applied to analyse the phosphorylation status of sarcomeric regulatory proteins, titin and of protein kinases AMPK, PKG, CaMKII as well as their expression. Protein kinase activity assays were used to measure activities of CaMKII, PKG and angiotensin-converting enzyme (ACE)., Results: TG male rats showed significantly higher mortality at 1 year than females or WT male rats. Left ventricular (LV) ejection fraction was specifically reduced in male, but not in female TG rats, while LV diastolic dysfunction was evident in both TG sexes, but LV hypertrophy, increased LV ACE activity, and reduced AMPK activity as evident from AMPK hypophosphorylation were specific to male rats. Sex differences were also observed in vascular and cardiomyocyte function showing different response to acetylcholine and Ca2+ -sensitivity of force production, respectively cardiomyocyte functional changes were associated with altered phosphorylation states of cardiac myosin binding protein C and cardiac troponin I phosphorylation in TG males only. Cardiomyocyte passive stiffness was increased in TG animals. On a molecular level titin phosphorylation pattern was altered, though alterations were sex-specific. Thus, also the reduction of PKG expression and activity was more pronounced in TG females. However, cardiomyocyte passive stiffness was restored by PKG and CaMKII treatments in both TG sexes., Conclusion: Here we demonstrated divergent sex-specific cardiovascular adaptation to the over-activation of the renin-angiotensin system in the rat. Higher mortality of male TG rats in contrast to female TG rats was observed as well as reduced LV systolic function, whereas females mainly developed HFpEF. Though both sexes developed increased myocardial stiffness to which an impaired titin function contributes to a sex-specific molecular mechanism. The functional derangements of titin are due to a sex-specific divergent regulation of PKG and CaMKII systems., (© 2024. The Author(s).)- Published
- 2024
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3. Oxidative stress and inflammation distinctly drive molecular mechanisms of diastolic dysfunction and remodeling in female and male heart failure with preserved ejection fraction rats.
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Zhazykbayeva S, Hassoun R, Herwig M, Budde H, Kovács Á, Mannherz HG, El-Battrawy I, Tóth A, Schmidt WE, Mügge A, and Hamdani N
- Abstract
Heart failure with preserved ejection fraction (HFpEF) is a complex cardiovascular insufficiency syndrome presenting with an ejection fraction (EF) of greater than 50% along with different proinflammatory and metabolic co-morbidities. Despite previous work provided key insights into our understanding of HFpEF, effective treatments are still limited. In the current study we attempted to unravel the molecular basis of sex-dependent differences in HFpEF pathology. We analyzed left ventricular samples from 1-year-old female and male transgenic (TG) rats homozygous for the rat Ren-2 renin gene (mRen2) characterized with hypertension and diastolic dysfunction and compared it to age-matched female and male wild type rats (WT) served as control. Cardiomyocytes from female and male TG rats exhibited an elevated titin-based stiffness (F
passive ), which was corrected to control level upon treatment with reduced glutathione indicating titin oxidation. This was accompanied with high levels of oxidative stress in TG rats with more prominent effects in female group. In vitro supplementation with heat shock proteins (HSPs) reversed the elevated Fpassive indicating restoration of their cytoprotective function. Furthermore, the TG group exhibited high levels of proinflammatory cytokines with significant alterations in apoptotic and autophagy pathways in both sexes. Distinct alterations in the expression of several proteins between both sexes suggest their differential impact on disease development and necessitate distinct treatment options. Hence, our data suggested that oxidative stress and inflammation distinctly drive diastolic dysfunction and remodeling in female and male rats with HFpEF and that the sex-dependent mechanisms contribute to HF pathology., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Zhazykbayeva, Hassoun, Herwig, Budde, Kovács, Mannherz, El-Battrawy, Tóth, Schmidt, Mügge and Hamdani.)- Published
- 2023
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4. In-depth analysis of T cell immunity and antibody responses in heterologous prime-boost-boost vaccine regimens against SARS-CoV-2 and Omicron variant.
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Heinen N, Marheinecke CS, Bessen C, Blazquez-Navarro A, Roch T, Stervbo U, Anft M, Plaza-Sirvent C, Busse S, Klöhn M, Schrader J, Vidal Blanco E, Urlaub D, Watzl C, Hoffmann M, Pöhlmann S, Tenbusch M, Steinmann E, Todt D, Hagenbeck C, Zimmer G, Schmidt WE, Quast DR, Babel N, Schmitz I, and Pfänder S
- Subjects
- Humans, Adult, COVID-19 Vaccines, CD8-Positive T-Lymphocytes, Antibody Formation, Leukocytes, Mononuclear, SARS-CoV-2, Cytokines, COVID-19 prevention & control, Vaccines
- Abstract
With the emergence of novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) Variants of Concern (VOCs), vaccination studies that elucidate the efficiency and effectiveness of a vaccination campaign are critical to assess the durability and the protective immunity provided by vaccines. SARS-CoV-2 vaccines have been found to induce robust humoral and cell-mediated immunity in individuals vaccinated with homologous vaccination regimens. Recent studies also suggest improved immune response against SARS-CoV-2 when heterologous vaccination strategies are employed. Yet, few data exist on the extent to which heterologous prime-boost-boost vaccinations with two different vaccine platforms have an impact on the T cell-mediated immune responses with a special emphasis on the currently dominantly circulating Omicron strain. In this study, we collected serum and peripheral blood mononuclear cells (PBMCs) from 57 study participants of median 35-year old's working in the health care field, who have received different vaccination regimens. Neutralization assays revealed robust but decreased neutralization of Omicron VOC, including BA.1 and BA.4/5, compared to WT SARS-CoV-2 in all vaccine groups and increased WT SARS-CoV-2 binding and neutralizing antibodies titers in homologous mRNA prime-boost-boost study participants. By investigating cytokine production, we found that homologous and heterologous prime-boost-boost-vaccination induces a robust cytokine response of CD4
+ and CD8+ T cells. Collectively, our results indicate robust humoral and T cell mediated immunity against Omicron in homologous and heterologous prime-boost-boost vaccinated study participants, which might serve as a guide for policy decisions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor JM declared a shared affiliation with the author MT at the time of review., (Copyright © 2022 Heinen, Marheinecke, Bessen, Blazquez-Navarro, Roch, Stervbo, Anft, Plaza-Sirvent, Busse, Klöhn, Schrader, Vidal Blanco, Urlaub, Watzl, Hoffmann, Pöhlmann, Tenbusch, Steinmann, Todt, Hagenbeck, Zimmer, Schmidt, Quast, Babel, Schmitz and Pfänder.)- Published
- 2022
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5. Low Risk of Severe Acute Respiratory Syndrome Coronavirus 2 Transmission by Fomites: A Clinical Observational Study in Highly Infectious Coronavirus Disease 2019 Patients.
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Meister TL, Dreismeier M, Blanco EV, Brüggemann Y, Heinen N, Kampf G, Todt D, Nguyen HP, Steinmann J, Schmidt WE, Steinmann E, Quast DR, and Pfaender S
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- Humans, SARS-CoV-2, Fomites, Pandemics, Viral Load, COVID-19, Communicable Diseases
- Abstract
Background: The contribution of droplet-contaminated surfaces for virus transmission has been discussed controversially in the context of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. More importantly, the risk of fomite-based transmission has not been systematically addressed. Therefore, the aim of this study was to evaluate whether confirmed hospitalized coronavirus disease 2019 (COVID-19) patients can contaminate stainless steel carriers by coughing or intensive moistening with saliva and to assess the risk of SARS-CoV-2 transmission upon detection of viral loads and infectious virus in cell culture., Methods: We initiated a single-center observational study including 15 COVID-19 patients with a high baseline viral load (cycle threshold value ≤25). We documented clinical and laboratory parameters and used patient samples to perform virus culture, quantitative polymerase chain reaction, and virus sequencing., Results: Nasopharyngeal and oropharyngeal swabs of all patients were positive for viral ribonucleic acid on the day of the study. Infectious SARS-CoV-2 could be isolated from 6 patient swabs (46.2%). After coughing, no infectious virus could be recovered, however, intensive moistening with saliva resulted in successful viral recovery from steel carriers of 5 patients (38.5%)., Conclusions: Transmission of infectious SARS-CoV-2 via fomites is possible upon extensive moistening, but it is unlikely to occur in real-life scenarios and from droplet-contaminated fomites., Competing Interests: Potential conflicts of interest . All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors declare no competing interests. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
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- 2022
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6. Whipple's disease - a rare and challenging complication in a patient with Crohn's disease.
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Bulut K, Markova A, Canbay AE, Schmidt WE, and Kahraman A
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- Anti-Bacterial Agents therapeutic use, Diarrhea diagnosis, Diarrhea etiology, Humans, Male, Tropheryma, Tumor Necrosis Factor Inhibitors, Crohn Disease complications, Crohn Disease diagnosis, Crohn Disease drug therapy, Whipple Disease complications, Whipple Disease diagnosis, Whipple Disease drug therapy
- Abstract
Introduction: Whipple's disease (WD) is a rare and infectious condition leading to multi-organ impairment caused by Tropheryma whipplei (TW), a ubiquitously occurring bacterium. TW can be detected in tissues by histological detection of PAS ("periodic acid-ship reaction")-positive macrophages and by polymerase-chain-reaction (PCR). Clinically, WD is often characterized by diarrhea, abdominal pain, and weight loss. These symptoms are also typical for a flare in Crohn's disease (CD) and, therefore, can lead to fatal misdiagnosis and wrong treatment by using biologics (e.g., anti-TNF-α)., Case Report: We here report a young male patient with pre-existing CD. The patient's symptoms were misinterpreted as a flare of CD and illustrate the multifaceted nature of WD. After intensifying immunosuppressive therapy, the patient developed therapy-refractory diarrhea with several opportunistic infections with a final, fatal outcome., Conclusion: Patients with inflammatory bowel disease (IBD) are not only at risk from infectious complications known with clostridium difficile or cytomegalovirus (CMV); infection with WD should also be ruled out by endoscopy and biopsy before the escalation of the immunosuppressive regime., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
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- 2022
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7. Low Serological Prevalence of SARS-CoV-2 Antibodies in Cancer Patients at a German University Oncology Center.
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Overheu O, Quast DR, Schmidt WE, Sakinç-Güler T, and Reinacher-Schick A
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- Antibodies, Viral, Humans, Prevalence, SARS-CoV-2, Universities, COVID-19 epidemiology, Neoplasms epidemiology
- Abstract
Background: Coronavirus disease 2019 (COVID-19) cases in Germany, as in most other places in Europe or worldwide, are still highly prevalent. Vaccination rates currently remain low, putting cancer patients at a continued risk of infection with SARS-CoV-2, while prevalence of SARS-CoV-2 antibodies among cancer patients in Germany remains essentially unknown., Methods: Between August 2020 and February 2021, patients admitted to our hospital were prospectively enrolled in our COVID-19 biobank. Collected sera were analyzed for SARS-CoV-2-IgM/IgG using Elecsys Anti-SARS-CoV-2 assay., Results: One hundred and ten patients with cancer were included in this study. With 71 (65%) patients, most had active cancer treatment, mainly chemotherapy (56%). The most frequent diagnosis was gastrointestinal cancer (54%) with pancreatic cancer being the most common cancer type (24%). Hematologic malignancies were present in 21 patients (17%). Among the cancer patients first diagnosed during the pandemic, the rate of palliative treatment situations tended to be higher (76% vs. 67%, p = 0.17). A history of SARS-CoV-2 infection was documented in 15 (14%) patients; however, SARS-CoV-2 antibodies were detected in 10 (67%) patients only. Of the patients without a history of SARS-CoV-2 infection, none displayed SARS-CoV-2 antibodies., Conclusion: In the present single-center experience, a low serological prevalence of SARS-CoV-2 antibodies among cancer patients even after SARS-CoV-2 infection was found. The results support continued strict preventive measures as well as efforts toward faster vaccination, due to a low immunity level in the population., (© 2021 S. Karger AG, Basel.)
- Published
- 2022
- Full Text
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