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1.
Arch Gynecol Obstet ; 309(6): 2771-2778, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38625545

RESUMO

PURPOSE: The primary objective of this study was to establish a benchmark by collecting baseline data on surgical education in obstetrics and gynecology in Germany, including factual number of operations performed. MATERIALS AND METHODS: A nationwide anonymous survey was conducted in Germany between January 2019 and July 2019 utilizing a specially designed questionnaire which addressed both residents and senior trainers. RESULTS: A total of 601 participants completed the survey, comprising 305 trainees and 296 trainers. The trainees reported performing a median of 125 non-obstetric surgeries (IQR: 41-332) and 75 obstetric procedures (IQR: 27-168) independently. While most last-year residents managed to meet the targeted numbers for minor surgical procedures outlined in the logbook, they fell short of achieving the required numbers for major operations, such as hysterectomies or more complex laparoscopies. Although both trainees and trainers emphasized the significance of surgical training, the overall quality of the training was rated poorly, particularly by trainees. This was attributed to a high proportion of administrative tasks and a deficiency in teaching time within the operating theater. External fellowship and mentoring programs, as well as the implementation of regular, centralized reviews of residency training, were identified as potentially beneficial by both trainees and trainers. CONCLUSION: The findings of this survey should serve as a wake-up call both within and outside of Germany, highlighting the importance of comprehensive and structured surgical training to enhance long-term patient care and increase satisfaction among obstetrics and gynecology trainees.


Assuntos
Ginecologia , Internato e Residência , Obstetrícia , Humanos , Obstetrícia/educação , Alemanha , Internato e Residência/estatística & dados numéricos , Ginecologia/educação , Feminino , Inquéritos e Questionários , Masculino , Adulto , Procedimentos Cirúrgicos em Ginecologia/educação , Procedimentos Cirúrgicos em Ginecologia/estatística & dados numéricos , Competência Clínica/estatística & dados numéricos , Pessoa de Meia-Idade
2.
Blood Adv ; 6(17): 5184-5197, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35819450

RESUMO

Megakaryocytes are large cells in the bone marrow that give rise to blood platelets. Platelet biogenesis involves megakaryocyte maturation, the localization of the mature cells in close proximity to bone marrow sinusoids, and the formation of protrusions, which are elongated and shed within the circulation. Rho GTPases play important roles in platelet biogenesis and function. RhoA-deficient mice display macrothrombocytopenia and a striking mislocalization of megakaryocytes into bone marrow sinusoids and a specific defect in G-protein signaling in platelets. However, the role of the closely related protein RhoB in megakaryocytes or platelets remains unknown. In this study, we show that, in contrast to RhoA deficiency, genetic ablation of RhoB in mice results in microthrombocytopenia (decreased platelet count and size). RhoB-deficient platelets displayed mild functional defects predominantly upon induction of the collagen/glycoprotein VI pathway. Megakaryocyte maturation and localization within the bone marrow, as well as actin dynamics, were not affected in the absence of RhoB. However, in vitro-generated proplatelets revealed pronouncedly impaired microtubule organization. Furthermore, RhoB-deficient platelets and megakaryocytes displayed selective defects in microtubule dynamics/stability, correlating with reduced levels of acetylated α-tubulin. Our findings imply that the reduction of this tubulin posttranslational modification results in impaired microtubule dynamics, which might contribute to microthrombocytopenia in RhoB-deficient mice. Importantly, we demonstrate that RhoA and RhoB are localized differently and have selective, nonredundant functions in the megakaryocyte lineage.


Assuntos
Megacariócitos , Trombocitopenia , Proteína rhoB de Ligação ao GTP/metabolismo , Animais , Plaquetas/metabolismo , Megacariócitos/metabolismo , Camundongos , Microtúbulos/metabolismo , Trombocitopenia/genética , Tubulina (Proteína)/metabolismo
3.
Thromb Res ; 217: 1-8, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810616

RESUMO

INTRODUCTION: Human immunodeficiency virus (HIV) in pregnant women is characterized by immune activation and inflammation despite suppressive antiretroviral therapy (ART). The extent to which ongoing inflammation contributes to activation of coagulation and fibrinolysis is unknown. MATERIALS AND METHODS: This cross-sectional study included pregnant women in the following three groups: HIV negative (n = 109), HIV infected virologically suppressed (n = 109) and HIV infected with HIV viral load (VL) of >50 copies/mL (n = 80). Fibrinolytic activity was evaluated by measuring d-dimer and plasminogen activator inhibitor-1 (PAI-1) as well as thrombin-antithrombin (TAT) complex concentrations, as an index of coagulation, in the first, second and third trimesters. RESULTS: In this population, with a mean age of 33 ± 6 years, pregnancy outcomes were recorded for 277 (93.0 %) participants with live births. HIV infected participants with virological suppression and VL of >50 copies/mL showed significantly increasing levels of d-dimer and PAI-1 in the first, second and third trimesters, as compared to HIV negative participants. No significant differences were observed between HIV infected participants with virological suppression and HIV infected participants with VL > 50 copies/mL for levels of first and third trimester d-dimer and PAI-1 in each trimester. In addition, TAT complex levels in the first trimester were significantly increased in HIV infected virologically suppressed participants as compared to HIV negative participants. CONCLUSION: HIV infected virologically suppressed pregnant women show evidence of persistently impaired markers of fibrinolysis. Future research should explore the risk of adverse pregnancy complications among HIV infected pregnant women in the modern era of ART.


Assuntos
Fibrinólise , Infecções por HIV , Adulto , Estudos Transversais , Feminino , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Inflamação , Inibidor 1 de Ativador de Plasminogênio , Gravidez , Gestantes
4.
Int J Lab Hematol ; 44(3): 635-642, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35132770

RESUMO

INTRODUCTION: Increased antiphospholipid antibodies (aPL) have been described in human immunodeficiency virus (HIV) infection. However, the association between aPL and the increased risk of thrombosis in HIV requires further clarification. METHODS: We reviewed the medical records of 215 consecutive women with a history of thrombosis and/or obstetric complications (158 HIV-uninfected and 57 HIV-infected) between July 2017 and March 2021. Participants (n = 215) without clinical criteria manifestations for antiphospholipid syndrome were included as matched controls. Testing for lupus anticoagulant (LAC), anticardiolipin (aCL) and anti-beta2-glycoprotein1 (aß2GP1) IgM and IgG was performed. RESULTS: Thirty-two (10.1%) HIV-uninfected and 15 (13.2%) HIV-infected participants were positive at baseline for one of the five criteria aPL, with no statistically significant difference. The profile of the HIV-infected participants with thrombosis (n = 11) included LAC in 15.8%, aCL IgG in 3.5% and aß2GP1 IgG in 1.8%. In contrast, the HIV-infected controls (n = 4), included aCL IgM in 1.8% and aß2GP1 IgM in 5.3%. Only LAC was significantly associated with thrombosis (p < 0.003). On repeat testing, in a HIV-infected sub-population, 2/7 with thrombosis were positive, while 3/3 controls tested negative. CONCLUSION: In contrast to earlier reports, the prevalence and expression of aPL in HIV-infected women with a history of thrombosis in the present study, in the era of antiretroviral therapy, were similar to HIV-uninfected women. Baseline LAC positivity was associated with a significantly increased risk for thrombosis in HIV. Future studies are recommended to explore additional coagulation abnormalities in HIV.


Assuntos
Síndrome Antifosfolipídica , Trombose , Anticorpos Anticardiolipina , Anticorpos Antifosfolipídeos , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Inibidor de Coagulação do Lúpus , Gravidez , beta 2-Glicoproteína I
5.
Clin Lab ; 67(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107617

RESUMO

BACKGROUND: Anticoagulation of pregnant woman with mechanical prosthetic heart valves is associated with significant maternal and fetal risks. METHODS: We describe a case of dorsal midline dysplasia in a fetus at 11 weeks' gestation. The mother was receiving warfarin therapy at a dose of 7.5 mg daily following a mechanical mitral valve replacement for rheumatic heart disease. RESULTS: Histological assessment revealed a meningocele with hemorrhage. No cerebellar or cerebral tissue was present in the skull confirming anencephaly. CONCLUSIONS: A multidisciplinary approach in pregnant women with mechanical prosthetic heart valves is essential in order to improve fetal outcomes.


Assuntos
Malformações do Sistema Nervoso , Complicações Cardiovasculares na Gravidez , Anticoagulantes/efeitos adversos , Feminino , Feto , Humanos , Gravidez , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Varfarina/efeitos adversos
6.
Cell Rep ; 35(6): 109102, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33979620

RESUMO

Megakaryocytes (MKs), the precursors of blood platelets, are large, polyploid cells residing mainly in the bone marrow. We have previously shown that balanced signaling of the Rho GTPases RhoA and Cdc42 is critical for correct MK localization at bone marrow sinusoids in vivo. Using conditional RhoA/Cdc42 double-knockout (DKO) mice, we reveal here that RhoA/Cdc42 signaling is dispensable for the process of polyploidization in MKs but essential for cytoplasmic MK maturation. Proplatelet formation is virtually abrogated in the absence of RhoA/Cdc42 and leads to severe macrothrombocytopenia in DKO animals. The MK maturation defect is associated with downregulation of myosin light chain 2 (MLC2) and ß1-tubulin, as well as an upregulation of LIM kinase 1 and cofilin-1 at both the mRNA and protein level and can be linked to impaired MKL1/SRF signaling. Our findings demonstrate that MK endomitosis and cytoplasmic maturation are separately regulated processes, and the latter is critically controlled by RhoA/Cdc42.


Assuntos
Citoplasma/metabolismo , Megacariócitos/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Humanos , Camundongos , Transdução de Sinais
7.
Int J Gynaecol Obstet ; 155(1): 110-118, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33448037

RESUMO

OBJECTIVE: To assess risk factors for venous thromboembolism (VTE) in African women in order to guide thromboprophylaxis. METHODS: A case-control study was performed at a specialist obstetric unit in South Africa from July 1, 2017 to June 30, 2020. We identified 128 cases with VTE and 640 controls, matched for gestation. RESULTS: Prepartum risk factors associated with VTE included; medical comorbidities (odds ratios [OR] 5.32, 95% confidence intervals [CI] 1.82-15.56), human immunodeficiency virus (HIV) (OR 2.84, 95% CI 1.50-5.41), and hospital admission or immobility (OR 5.33, 95% CI 1.17-24.22). Postpartum, the following were identified as significant risk factors; medical comorbidities (OR 23.72, 95% CI 8.75-64.27), hospital admission or immobility (OR 13.18, 95% CI 5.04-34.49), systemic infection (OR 4.48, 95% CI 1.28-15.68), HIV (OR 3.20, 95% CI 1.49-6.87), pre-eclampsia and fetal growth restriction (OR 2.74, 95% CI 1.18-6.36), and postpartum hemorrhage (OR 4.38, 95% CI 1.75-10.97). Antiretroviral therapy, opportunistic infections, and viral load >50 copies/ml, however, were not associated with VTE risk among HIV-infected participants. CONCLUSION: HIV was a significant risk factor for pregnancy-related thrombosis. This was independent of traditional HIV risk factors. As such, future studies are recommended to explore the mechanisms of thrombosis associated with HIV infection.


Assuntos
Infecções por HIV , Tromboembolia Venosa , Anticoagulantes , Estudos de Casos e Controles , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Gravidez , Fatores de Risco , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia
8.
Radiology ; 244(2): 514-23, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17562811

RESUMO

PURPOSE: To prospectively evaluate the influence of superparamagnetic iron oxide (SPIO) or ultrasmall SPIO (USPIO) particles on the surface epitope pattern of adult mesenchymal stem cells (MSCs) by regulating the expression of transferrin receptor and to prospectively evaluate the influence of transfection agents (TAs) on the uptake of SPIO or USPIO particles in MSCs. MATERIALS AND METHODS: The study was approved by the institutional animal care committee of the University of Tübingen. MSCs were isolated from the bone marrow of four rats. To obtain highly homogeneous MSC populations, MSCs from one rat were single-cell cloned. One MSC clone was characterized and selected for the labeling experiments. The MSCs, which were characterized with flow cytometry and in vitro differentiation, were labeled with 200 microg/mL SPIO or USPIO or with 60 microg/mL SPIO or USPIO in combination with TAs. Aggregations of labeled cells were accommodated inside a defined volume in an agar gel matrix. Magnetic resonance (MR) imaging was performed to measure SPIO- or USPIO-induced signal voids. Quantification of cellular total iron load (TIL) (intracellular iron plus iron coating the cellular surface), determination of cellular viability, and electron microscopy were also performed. RESULTS: Labeling of MSCs with SPIO or USPIO was feasible without affecting cell viability (91.1%-94.7%) or differentiation potential. For MR imaging, SPIO plus a TA was most effective, depicting 5000 cells with an average TIL of 76.5 pg per cell. SPIO or USPIO particles in combination with TAs coated the cellular surface but were not incorporated into cells. In nontransfected cells, SPIO or USPIO was taken up. MSCs labeled with SPIO or USPIO but without a TA showed enhanced expression of transferrin receptor, in contrary to both MSCs labeled with SPIO or USPIO and a TA and control cells. CONCLUSION: SPIO or USPIO labeling without TAs has an influence on gene expression of MSCs upregulating transferrin receptor. Furthermore, SPIO labeling with a TA will coat the cellular surface.


Assuntos
Meios de Contraste/farmacocinética , Ferro/farmacocinética , Imageamento por Ressonância Magnética/métodos , Células-Tronco Mesenquimais , Óxidos/farmacocinética , Receptores da Transferrina/metabolismo , Animais , Dextranos , Estudos de Viabilidade , Óxido Ferroso-Férrico , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Nanopartículas de Magnetita , Masculino , Tamanho da Partícula , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , Transfecção , Regulação para Cima
9.
Stem Cells ; 24(10): 2220-31, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16794266

RESUMO

Adult mesenchymal stem cells (aMSCs) are a stem cell population present in bone marrow, which can be isolated and expanded in culture and characterized. Due to the lack of specific surface markers, it is difficult to separate the MSCs from bone marrow directly. Here, we present a novel method using high-specific nucleic acids called aptamers. Porcine MSCs were used as a target to generate aptamers by combinatorial chemistry out of a huge random library with in vitro technology called systematic evolution of ligands by exponential enrichment (SELEX). After cloning and sequencing, the binding affinity was detected using a cell-sorting assay with streptavidin-coated magnetic microbeads. We also used 12-well plates immobilized with aptamers to fish out MSCs from the cell solution and a fluorescein isothiocyanate-labeled aptamer to sort MSCs from bone marrow using high-speed fluorescence-activated cell sorting. The cells showed high potency to differentiate into osteogenic, as well as into adipogenic, lineages with typical morphological characteristics. Surface marker staining showed that the attached cells were CD29(+), CD44(+), CD45(-), CD90(+), SLA class I(+), SLA DQ(-), and SLA DR(-). Compared with existing methods, this study established a novel, rapid, and efficient method for direct isolation of aMSCs from porcine bone marrow by using an aptamer as a probe to fish out the aMSCs. This new application of aptamers can facilitate aMSC isolation and enrichment greatly, thereby enhancing the rate of aMSC-derived cells after in vitro differentiation for various applications in the emerging field of tissue engineering and regenerative medicine.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Células da Medula Óssea/citologia , Medula Óssea/metabolismo , Células-Tronco Mesenquimais/citologia , Animais , Células da Medula Óssea/metabolismo , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Citometria de Fluxo , Células-Tronco Mesenquimais/metabolismo , Reprodutibilidade dos Testes , Suínos
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