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101.
The placenta is a vital, multi-functional organ that acts as an interface between maternal and fetal circulation during pregnancy. Nutritional deficiencies during pregnancy alter placental development and function, leading to adverse pregnancy outcomes, such as pre-eclampsia, infants with small for gestational age and low birthweight, preterm birth, stillbirths and maternal mortality. Maternal nutritional supplementation may help to mitigate the risks, but the evidence base is difficult to navigate. The primary purpose of this umbrella review is to map the evidence on the effects of maternal nutritional supplements and dietary interventions on pregnancy outcomes related to placental disorders and maternal mortality. A systematic search was performed on seven electronic databases, the PROSPERO register and references lists of identified papers. The results were screened in a three-stage process based on title, abstract and full-text by two independent reviewers. Randomized controlled trial meta-analyses on the efficacy of maternal nutritional supplements or dietary interventions were included. There were 91 meta-analyses included, covering 23 types of supplements and three types of dietary interventions. We found evidence that supports supplementary vitamin D and/or calcium, omega-3, multiple micronutrients, lipid-based nutrients, and balanced protein energy in reducing the risks of adverse maternal and fetal health outcomes. However, these findings are limited by poor quality of evidence. Nutrient combinations show promise and support a paradigm shift to maternal dietary balance, rather than single micronutrient deficiencies, to improve maternal and fetal health. The review is registered at PROSPERO (CRD42020160887).  相似文献   
102.
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells.  相似文献   
103.
International Urology and Nephrology - To test the value of preoperative and postoperative cystatin C (CysC) as a predictor on kidney function after partial (PN) or radical nephrectomy (RN) in...  相似文献   
104.
BackgroundDiffuse large B-cell lymphoma (DLBCL) is the most common subtype of non–Hodgkin lymphoma in the posttransplant setting. Treatment is based on chemotherapy; surgery is still debated and should be performed in very select cases.MethodsWe observed 2 patients out of 300 who underwent lung transplantation in the Nouvel Hopital Civil between 2013 and 2019 with primary hepatic lymphoma. Chemotherapy with a rituximab-cyclophosphamide, hydroxydaunorubicin, vincristine, prednisone protocol was performed in all patients. Mycophenolate mofetil was interrupted before treatment, and everolimus was introduced after chemotherapy by associating tacrolimus withdrawal.ResultsOne patient showed complete remission; after 7 years, no recurrence has been noticed. The second is still undergoing chemotherapy with no signs of disease progression.ConclusionsDLBCL risk is higher in solid organ transplant recipients than in the general population. Primary hepatic lymphoma diagnosis is often difficult and based on histologic findings after initial clinical and radiological suspicion of primary or secondary liver neoplasia. Diagnosis is challenging because no clinical, radiological, or biological features exist. Biopsy is always indicated for histologic confirmation. Chemotherapy is the mainstay of therapy, but surgery may be indicated in very select patients.  相似文献   
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Belatacept may increase cytomegalovirus (CMV) disease risk after conversion from CNI-based therapy. We analyzed CMV disease characteristics after belatacept conversion. Propensity score matching was used to compare CMV disease incidence in belatacept- and CNI-treated kidney transplant recipients (KTRs). CMV disease characteristics and risk factors under belatacept were analyzed. In total, 223 KTRs (median age [IQR] 59.2 years [45.4–68.5]) were converted to belatacept (median of 11.5 months [2.5–37.0] post-transplantation); 40/223 (17.9%) developed CMV disease. Independent risk factors included increased age (p = .0164), D+/R− CMV serostatus (p = .0220), and low eGFR at conversion (p = .0355). Among 181 belatacept-treated patients matched to 181 controls, 32/181 (17.7%) experienced CMV disease (vs. 5/181 controls [2.8%]). CMV disease cumulative incidences were 6.33 and 0.91/100 person-years (p-y) in belatacept and control groups, respectively. CMV disease risk was particularly high in elderly patients (converted >70 years) and those with eGFR <30 ml/min; cumulative incidences were 18.4 and 5.2/100 p-y, respectively. CMV diseases under belatacept were atypical, with late-onset disease (24/40 patients [60%]), high CMV seropositivity (27/40, 67%), increased severe and tissue-invasive disease rates (gastrointestinal involvement in 32/40 [80%]) and life-threatening diseases (4/40 [10%]). These findings should stimulate further research to secure the use of belatacept as a valuable rescue therapy in KTRs.  相似文献   
108.
Human lymphocytes derived from a lymph node draining a primary breast adenocarcinoma were fused with the mouse myeloma P3X63Ag8.653 to generate human-mouse hybridomas secreting human monoclonal antibodies (MAbs) to tumor associated antigens (TAAs). One of the resulting human MAbs, YBB 190 (IgM) is described. Enzyme-linked immunosorbent assays (ELISA) employing membrane and cytosol fractions of human tissues demonstrated YBB 190 reactivity against cytosol but not membrane components of malignant and normal epithelial tissues. When tested by an indirect immunoperoxidase staining method against fresh frozen human tissue sections, YBB 190 reacted with malignant cells in 26 of 28 epithelial cancers and with normal epithelia in 11 different benign tissues. Preliminary western blot antigen characterization indicated that YBB 190 recognizes cytokeratin intermediate filaments, or a protein that is closely associated with cytokeratins. These data indicate that B cells with specificity for intermediate filaments are present in tumor draining lymph nodes. Our findings provide insights into the nature of potential autoimmune responses in cancer patients and suggest that improved tumor directed sensitization procedures may be required to more effectively utilize lymphocytes from tumor draining lymph nodes to generate therapeutically useful human MAbs to TAAs.  相似文献   
109.
Alterations of gamma aminobutyric acid (GABA)-mediated neurotransmission have been implicated in the pathogenesis of epilepsies. Here we examine the distribution of the GABAA receptor in the hippocampus of 78 surgical specimens from patients with chronic pharmacoresistant focal epilepsies. The receptor was localized immunohistochemically with the monoclonal antibody bd-24 which selectively recognizes the 1 subunit of the GABAA receptor. The results were compared with the receptor distribution of 28 normal hippocampal specimens obtained at autopsy. In the great majority of the surgical specimens a loss of GABAA receptor immunoreactivity was present in CA1 (92.3%), CA4 (78.2%), the dentate granular cell layer (70.5%) and the molecular layer of the dentate gyrus (65.4%). The subiculum revealed a normal staining pattern in all but 4 cases. In no instance did we observe an increase of immunoreactivity in any region or cell population. The decrease of GABAA receptor immunoreactivity was closely related to neuronal loss in the respective specimen and to Ammon's horn sclerosis. There was no correlation between GABAA receptor loss and the patient's age at surgery, duration of seizures, age at onset of seizures and to the presence or absence of secondary generalized tonic clonic seizures. The data suggest that the observed loss of GABAA receptor immunoreactivity is a secondary phenomenon rather than an event that is relevant for the pathogenesis of epileptic seizures.  相似文献   
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