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排序方式: 共有6299条查询结果,搜索用时 15 毫秒
991.
Alaa Alkhalaf Astrid Klooster Willem van Oeveren Ulrike Achenbach Nanne Kleefstra Robbert J. Slingerland G. Sophie Mijnhout Henk J.G. Bilo Reinold O.B. Gans Gerjan J. Navis Stephan J.L. Bakker 《Diabetes care》2010,33(7):1598-1601
OBJECTIVE
To investigate the effect of benfotiamine on urinary albumin excretion (UAE) and the tubular damage marker kidney injury molecule-1 (KIM-1) in patients with type 2 diabetes and nephropathy.RESEARCH DESIGN AND METHODS
Patients with type 2 diabetes and UAE equivalent to 15–300 mg/24 h, despite ACE inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs), were randomly assigned to 12 weeks of benfotiamine (900 mg/day) (n = 39) or placebo (n = 43).RESULTS
Compared with placebo, benfotiamine treatment resulted in significant improvement of thiamine status (P < 0.001). Benfotiamine treatment did not significantly decrease 24-h UAE or 24-h KIM-1 excretion.CONCLUSIONS
In patients with type 2 diabetes and nephropathy, high-dose benfotiamine treatment for 12 weeks in addition to ACE-Is or ARBs did not reduce UAE or KIM-1 excretion, despite improvement of thiamine status.The pathophysiology of diabetic nephropathy includes albuminuria as a consequence of glomerular endothelial damage and further progression due to tubulointerstitial inflammation and fibrosis (1,2). Despite protective treatment with ACE inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs), many patients progress to end-stage renal disease (3).Thiamine and benfotiamine have been proposed as protective agents for diabetes complications (4,5). Benfotiamine is a lipophilic thiamine derivative with high bioavailability (6). In animal studies, both compounds had beneficial effects on microvascular complications, including diabetic nephropathy (5,7).We investigated whether benfotiamine results in reduction in urinary albumin excretion (UAE) or tubulointerstitial damage markers in patients with type 2 diabetes and increased UAE despite ACE-Is or ARBs. 相似文献992.
Arne Sattler Eva Schrezenmeier Ulrike A. Weber Alexander Potekhin Friederike Bachmann Henriette Straub-Hohenbleicher Klemens Budde Elena Storz Vanessa Proß Yasmin Bergmann Linda M.L. Thole Caroline Tizian Oliver Hlsken Andreas Diefenbach Hubert Schrezenmeier Bernd Jahrsdrfer Tomasz Zemojtel Katharina Jechow Christian Conrad Sren Lukassen Diana Stauch Nils Lachmann Mira Choi Fabian Halleck Katja Kotsch 《The Journal of clinical investigation》2021,131(14)
Novel mRNA-based vaccines have been proven to be powerful tools in combating the global pandemic caused by SARS-CoV-2, with BNT162b2 (trade name: Comirnaty) efficiently protecting individuals from COVID-19 across a broad age range. Still, it remains largely unknown how renal insufficiency and immunosuppressive medication affect development of vaccine-induced immunity. We therefore comprehensively analyzed humoral and cellular responses in kidney transplant recipients after the standard second vaccination dose. As opposed to all healthy vaccinees and the majority of hemodialysis patients, only 4 of 39 and 1 of 39 transplanted individuals showed IgA and IgG seroconversion at day 8 ± 1 after booster immunization, with minor changes until day 23 ± 5, respectively. Although most transplanted patients mounted spike-specific T helper cell responses, frequencies were significantly reduced compared with those in controls and dialysis patients and this was accompanied by a broad impairment in effector cytokine production, memory differentiation, and activation-related signatures. Spike-specific CD8+ T cell responses were less abundant than their CD4+ counterparts in healthy controls and hemodialysis patients and almost undetectable in transplant patients. Promotion of anti-HLA antibodies or acute rejection was not detected after vaccination. In summary, our data strongly suggest revised vaccination approaches in immunosuppressed patients, including individual immune monitoring for protection of this vulnerable group at risk of developing severe COVID-19. 相似文献
993.
Andreas Kupz Ulrike Zedler Manuela St?ber Carolina Perdomo Anca Dorhoi Roland Brosch Stefan H.E. Kaufmann 《The Journal of clinical investigation》2016,126(6):2109-2122
IFN-γ is a critical mediator of host defense against Mycobacterium tuberculosis (Mtb) infection. Antigen-specific CD4+ T cells have long been regarded as the main producer of IFN-γ in tuberculosis (TB), and CD4+ T cell immunity is the main target of current TB vaccine candidates. However, given the recent failures of such a TB vaccine candidate in clinical trials, strategies to harness CD4-independent mechanisms of protection should be included in future vaccine design. Here, we have reported that noncognate IFN-γ production by Mtb antigen–independent memory CD8+ T cells and NK cells is protective during Mtb infection and evaluated the mechanistic regulation of IFN-γ production by these cells in vivo. Transfer of arenavirus- or protein-specific CD8+ T cells or NK cells reduced the mortality and morbidity rates of mice highly susceptible to TB in an IFN-γ–dependent manner. Secretion of IFN-γ by these cell populations required IL-18, sensing of mycobacterial viability, Mtb protein 6-kDa early secretory antigenic target–mediated (ESAT-6–mediated) cytosolic contact, and activation of NLR family pyrin domain–containing protein 3 (NLRP3) inflammasomes in CD11c+ cell subsets. Neutralization of IL-18 abrogated protection in susceptible recipient mice that had received noncognate cells. Moreover, improved Mycobacterium
bovis bacillus Calmette-Guérin (BCG) vaccine–induced protection was lost in the absence of ESAT-6–dependent cytosolic contact. Our findings provide a comprehensive mechanistic framework for antigen-independent IFN-γ secretion in response to Mtb with critical implications for future intervention strategies against TB. 相似文献
994.
995.
Kruszewska D Sahl HG Bierbaum G Pag U Hynes SO Ljungh A 《The Journal of antimicrobial chemotherapy》2004,54(3):648-653
OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) often colonize the anterior nares, and nasal carriage remains the main source of bacterial dissemination. The aim of this study was to assess the in vivo activity of the lantibiotic mersacidin against MRSA colonizing nasal epithelia. METHODS: The efficiency of mersacidin in the eradication of MRSA was tested employing mice pre-treated with hydrocortisone and inoculated intranasally either three or six times with a bacterial suspension. RESULTS: In mersacidin-treated animals, pre-colonized with MRSA, bacteria could not be detected in blood, lungs, liver, kidney, spleen or nasal scrapings and there were no lesions manifested after intraperitoneal drug application. Blood samples from infected mice obtained 2 h after mersacidin therapy revealed anti-MRSA activity in a serum bactericidal test. Moreover, elevated interleukin-1beta and tumour necrosis factor-alpha titres were noticed in the pre-infected but not in cured animals. In contrast, mersacidin did not induce differences in the cytokine profiles of treated uninfected control mice. CONCLUSIONS: In the mouse rhinitis model, mersacidin was able to eradicate MRSA colonization. The site of action (epithelium versus blood) of mersacidin needs to be further explored. 相似文献
996.
Seifert U Liermann H Racanelli V Halenius A Wiese M Wedemeyer H Ruppert T Rispeter K Henklein P Sijts A Hengel H Kloetzel PM Rehermann B 《The Journal of clinical investigation》2004,114(2):250-259
The high incidence of hepatitis C virus (HCV) persistence raises the question of how HCV interferes with host immune responses. Studying a single-source HCV outbreak, we identified an HCV mutation that impaired correct carboxyterminal cleavage of an immunodominant HLA-A2-restricted CD8 cell epitope that is frequently recognized by recovered patients. The mutation, a conservative HCV nonstructural protein 3 (NS3) tyrosine to phenylalanine substitution, was absent in 54 clones of the infectious source, but present in 15/21 (71%) HLA-A2-positive and in 11/24 (46%) HLA-A2-negative patients with chronic hepatitis C. In order to analyze whether the mutation affected the processing of the HLA-A2-restricted CD8 cell epitope, mutant and wild-type NS3 polypeptides were digested in vitro with 20S constitutive proteasomes and with immunoproteasomes. The presence of the mutation resulted in impaired carboxyterminal cleavage of the epitope. In order to analyze whether impaired epitope processing affected T cell priming in vivo, HLA-A2-transgenic mice were infected with vaccinia viruses encoding either wild-type or mutant HCV NS3. The mutant induced fewer epitope-specific, IFN-gamma;-producing and fewer tetramer(+) cells than the wild type. These data demonstrate how a conservative mutation in the flanking region of an HCV epitope impairs the induction of epitope-specific CD8(+) T cells and reveal a mechanism that may contribute to viral sequence evolution in infected patients. 相似文献
997.
Peiniger S Nienaber U Lefering R Braun M Wafaisade A Wutzler S Borgmann M Spinella PC Maegele M;Trauma Registry of the Deutsche Gesellschaft für Unfallchirurgie 《Critical care (London, England)》2011,15(1):R68
Introduction
Retrospective studies have demonstrated a potential survival benefit from transfusion strategies using an early and more balanced ratio between fresh frozen plasma (FFP) concentration and packed red blood cell (pRBC) transfusions in patients with acute traumatic coagulopathy requiring massive transfusions. These results have mostly been derived from non-head-injured patients. The aim of the present study was to analyze whether a regime using a high FFP:pRBC transfusion ratio (FFP:pRBC ratio >1:2) would be associated with a similar survival benefit in severely injured patients with traumatic brain injury (TBI) (Abbreviated Injury Scale (AIS) score, head ≥3) as demonstrated for patients without TBI requiring massive transfusion (≥10 U of pRBCs). 相似文献998.
999.
Jan-Michael Prill Sigrid Espenlaub Ulrike Samen Tatjana Engler Erika Schmidt Francesco Vetrini Amanda Rosewell Nathan Grove Donna Palmer Philip Ng Stefan Kochanek Florian Kreppel 《Molecular therapy》2011,19(1):83-92
In vivo gene transfer with adenovirus vectors would significantly benefit from a tight control of the adenovirus-inherent liver tropism. For efficient hepatocyte transduction, adenovirus vectors need to evade from Kupffer cell scavenging while delivery to peripheral tissues or tumors could be improved if both scavenging by Kupffer cells and uptake by hepatocytes were blocked. Here, we provide evidence that a single point mutation in the hexon capsomere designed to enable defined chemical capsid modifications may permit both detargeting from and targeting to hepatocytes with evasion from Kupffer cell scavenging. Vector particles modified with small polyethylene glycol (PEG) moieties specifically on hexon exhibited decreased transduction of hepatocytes by shielding from blood coagulation factor binding. Vector particles modified with transferrin or, surprisingly, 5,000 Da PEG or dextran increased hepatocyte transduction up to 18-fold independent of the presence of Kupffer cells. We further show that our strategy can be used to target high-capacity adenovirus vectors to hepatocytes emphasizing the potential for therapeutic liver-directed gene transfer. Our approach may lead to a detailed understanding of the interactions between adenovirus vectors and Kupffer cells, one of the most important barriers for adenovirus-mediated gene delivery. 相似文献
1000.
Gerdemann U Katari U Christin AS Cruz CR Tripic T Rousseau A Gottschalk SM Savoldo B Vera JF Heslop HE Brenner MK Bollard CM Rooney CM Leen AM 《Molecular therapy》2011,19(12):2258-2268
Although immunotherapy with Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) can treat EBV-associated Hodgkin and non-Hodgkin lymphoma (HL/NHL), more than 50% of such tumors are EBV negative. We now describe an approach that allows us to consistently generate, in a single line, CTLs that recognize a wide spectrum of nonviral tumor-associated antigens (TAAs) expressed by human HL/NHL, including Survivin, MAGE-A4, Synovial sarcoma X (SSX2), preferentially expressed antigen in melanoma (PRAME) and NY-ESO-1. We could generate these CTLs from nine of nine healthy donors and five of eight lymphoma patients, irrespective of human leukocyte antigen (HLA) type. We reactivated TAA-directed T cells ex vivo, by stimulation with dendritic cells (DCs) pulsed with overlapping peptide libraries spanning the chosen antigens in the presence of an optimized Th1-polarizing, prosurvival/proliferative and Treg inhibitory cytokine combination. The resultant lines of CD4(+) and CD8(+), polycytokine-producing T cells are directed against a multiplicity of epitopes expressed on the selected TAAs, with cytolytic activity against autologous tumor cells. Infusion of such multispecific monocultures may extend the benefits of CTL therapy to treatment even of EBV negative HL and NHL. 相似文献