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101.
Gisela Soledad Gualdoni Martín Ricardo Ventureira Tamara Anahí Coll Wilder Alberto Palomino Claudio Gustavo Barbeito Elisa Cebral 《Reproductive biomedicine online》2021,42(3):481-504
Research questionMaternal alcohol consumption produces fetal retardation and malformations, probably associated with placental defects. Does perigestational alcohol consumption up to organogenesis lead to abnormal placentation and embryo growth restriction by disrupting the vascular endothelial growth factor (VEGF) system in embryo–placental development?DesignFemale mice were treated with 10% ethanol in drinking water before and up to day 10 of gestation. Control mice received ethanol-free water. After treatment, the trophoblastic tissue, embryo growth and the angiogenic VEGF pathway were analysed.ResultsFemale mice who had received treatment had resorbed and delayed implantation sites with poor ectoplacental cone development. Reduced trophoblastic area tissue from female mice who had received treatment had abnormal junctional zone and diminished labyrinthine vascularization. After treatment, the labyrinth had increased chorionic trophoblast proliferation, hypoxia inducible factor-1α immunoexpression but reduced apoptosis. The embryo growth was reduced concomitantly with low VEGF immunostaining but high endothelial nitric oxide synthase (eNOS) expression. In junctional and labyrinth of treated female mice, gene and protein immunoexpression of VEGF was reduced and the protein expression of FLT-1 increased compared with controls. Increased activation of kinase insert domain receptor receptor (phosphorylated KDR) and expression of eNOS were observed in placenta of treated female mice. Immunoexpression of metalloproteinase-9, however, was reduced in junctional zone but increased in labyrinth, compared with controls.ConclusionsThese data reveal inadequate expression of VEGF/receptors and angiogenic eNOS and metalloproteinase factors related to abnormal early placentation after perigestational alcohol ingestion, providing insight into aetiological factors underlying early placentopathy associated with intrauterine growth restriction caused by maternal alcohol consumption. 相似文献
102.
Bickert T Wohlleben G Brinkman M Trujillo-Vargas CM Ruehland C Reiser CO Hess J Erb KJ 《Medical microbiology and immunology》2007,196(1):31-39
We analysed the effects of murine polyomavirus-like particles (PLPs) on bone marrow-derived dendritic cells (BMDCs) and T cells in vitro. BMDCs activated with PLPs up-regulated CD40, CD80, CD86 and major histocompatibility complex (MHC) class II surface markers and produced proinflammatory cytokines. Chimeric PLPs [expressing the ovalbumin (OVA)-peptides OVA(257-264) or OVA(323-339)], but not wildtype PLPs, activated OVA-specific CD8 T cells and OVA-specific CD4 T cells, respectively, indicating both MHC class I and II presentation of the peptides by antigen-presenting cells. Our results suggest that PLPs may be used as vaccine adjuvants priming dendritic cells to induce potent T cell responses. 相似文献
103.
Rochelle W Tyl Christina B Myers Melissa C Marr Carol S Sloan Nora P Castillo M Michael Veselica John C Seely Stephen S Dimond John P Van Miller Ronald S Shiotsuka Gisela D Stropp John M Waechter Steven G Hentges 《Toxicological sciences》2008,102(2):392-412
No information exists on reproductive/developmental effects in mice exposed to dietary 17beta-estradiol (E2) over multiple generations. Therefore, under OECD Test Guideline 416 with enhancements, CD-1 mice (F0 generation, 25 mice/sex/group) were exposed to dietary E2 at 0, 0.001, 0.005, 0.05, 0.15, or 0.5 ppm ( approximately 0, 0.2, 1, 10, 30, or 100 mug E2/kg body weight/day) for 8 weeks prebreed, 2 weeks mating, approximately 3 weeks gestation, and 3 weeks lactation. At weaning, selected F1 offspring (F1 parents; 25/sex/group) and extra retained F1 males (one per litter) were exposed to the same dietary concentrations and durations as the F0 generation; study termination occurred at F2 weaning; F1/F2 weanlings (up to three per sex per litter) were necropsied with organs weighed. At 0.5 ppm, effects were increased F1/F2 perinatal loss, prolonged F0/F1 gestational length, reduced numbers of F2 (but not F1) litters/group, reduced F1/F2 litter sizes, accelerated vaginal patency (VP) and delayed preputial separation (PPS), increased uterus + cervix + vagina weights (UCVW) in F0/F1 adults and F1/F2 weanlings, and decreased testes and epididymides weights (TEW) in F1/F2 weanlings. At 0.15 ppm, effects were increased UCVW in F0/F1 adults and F1/F2 weanlings, accelerated VP, delayed PPS, and reduced TEW in F1/F2 weanlings. At 0.05 ppm, UCVW were increased in F1/F2 weanlings, and PPS was delayed only in extra retained F1 males. There were no biologically significant or treatment-related effects on F0/F1 parental body weights, feed consumption, or clinical observations, or on F0/F1 estrous cyclicity, F0/F1 andrology, or F1/F2 anogenital distance at any dose. The no observable effect level was 0.005 ppm E2 ( approximately 1 mug/kg/day). Therefore, the mouse model is sensitive to E2 by oral administration, with effects on reproductive development at doses of 10- 100 mug/kg/day. 相似文献
104.
The flavonol quercetin activates basolateral K(+) channels in rat distal colon epithelium 总被引:2,自引:0,他引:2
1. The flavonol quercetin has been shown to activate a Cl(-) secretion in rat colon. Unlike the secretory activity of the related isoflavone genistein, quercetin's secretory activity does not depend on cyclic AMP; instead, it depends on Ca(2+). We investigated the possible involvement of Ca(2+) dependent basolateral K(+) channels using apically permeabilized rat distal colon epithelium mounted in Ussing chambers. 2. In intact epithelium, quercetin induced an increase in short-circuit current (I(sc)), which was diminished by the Cl(-) channel blockers NPPB and DPC, but not by glibenclamide, DIDS or anthracene-9-carboxylic acid. The effect of the flavonol was also inhibited by several serosally applied K(+) channel blockers (Ba(2+), quinine, clotrimazole, tetrapentylammonium, 293B), whereas other K(+) channel blockers failed to influence the quercetin-induced increase in I(sc) (tetraethylammonium, charybdotoxin). 3. The apical membrane was permeabilized by mucosal addition of nystatin and a serosally directed K(+) gradient was applied. The successful permeabilization was confirmed by experiments demonstrating the failure of bumetanide to inhibit the carbachol-induced current. 4. In apically permeabilized epithelium, quercetin induced a K(+) current (I(K)), which was neither influenced by ouabain nor by bumetanide. Whereas DPC, NPPB, charybdotoxin and 293B failed to inhibit this I(K), quinine, Ba(2+), clotrimazole and tetrapentylammonium were effective blockers of this current. 5. We conclude from these results that at least part of the quercetin-induced Cl(-) secretion can be explained by an activation of basolateral K(+) channels. 相似文献
105.
Becker A Grecksch G Kraus J Loh HH Schroeder H Höllt V 《Naunyn-Schmiedeberg's archives of pharmacology》2002,365(4):296-302
To investigate the role of mu opioid receptors in the reinforcing effects of psychotropic drugs, the voluntary ethanol intake and ethanol- and cocaine-induced conditioned place preference in mu opioid receptor-deficient mice and their wild-type counterpartners was tested. Moreover, dopamine D1 and D2 receptor binding was measured. It was found that ethanol intake was significantly lower in deficient mice. Conditioned place preference in wild-type animals was induced with 5.0 mg/kg cocaine and this dose was ineffective in the knockouts. In this group conditioned place preference occurred after injection of 10.0 mg/kg cocaine. Cocaine induced a similar increase in locomotor activity in both groups of mice. There was no difference in dopamine D1 receptor binding, whereas dopamine D2 receptor binding was significantly lower in the hippocampus of deficient animals. This suggests that interaction between opioid systems and dopaminergic systems may account for the differences in responding to the drugs. 相似文献
106.
Analysis of TP53 and PTEN in gliomatosis cerebri 总被引:5,自引:0,他引:5
Mawrin C Kirches E Schneider-Stock R Scherlach C Vorwerk C Von Deimling A Van Landeghem F Meyermann R Bornemann A Müller A Romeike B Stoltenburg-Didinger G Wickboldt J Pilz P Dietzmann K 《Acta neuropathologica》2003,105(6):529-536
Gliomatosis cerebri (GC) is a rare glial neoplasm with extensive diffuse brain infiltration but relative preservation of the underlying architecture. Previous molecular studies, mostly analyzing biopsy samples, have suggested an astrocytic origin of GC, but a larger collective of autopsy tissue has not been investigated so far. Furthermore, whether the widespread neoplastic infiltration is based on a monoclonal process is still a matter of debate. In the present study, we screened paraffin-embedded brain tissue from different areas of 18 cases (8 autopsy cases and 10 biopsies) for alterations in the TP53 and PTEN genes. Nuclear accumulation of p53 protein was detected in 9 cases (50%). Somatic TP53 mutations occurred in two autopsy cases (11% of all cases). In the first case, a C-->T transition in codon 273 (Arg-->Cys) was detected in all tumor samples. In the second case, in tumor samples from one hemisphere, nuclear accumulation of p53 was caused by a G-->A transition in codon 244 (Gly-->Asp). In the present series, no mutations within the coding region of PTEN were found. Pten expression was observed in two autopsy cases (25%) and seven biopsy samples (70%). These data suggest that TP53 is affected in some cases, but other yet-unidentified genetic alterations might contribute to tumorigenesis in GC. Furthermore, although GC might be a monoclonal process, the presence of different tumor clones cannot be ruled out. 相似文献
107.
Treatment of severe lichen planus with mycophenolate mofetil 总被引:2,自引:0,他引:2
Frieling U Bonsmann G Schwarz T Luger TA Beissert S 《Journal of the American Academy of Dermatology》2003,49(6):1063-1066
Lichen planus (LP) is an inflammatory skin disorder with a wide range of clinical appearances. The treatment of disseminated and especially erosive forms of LP is often difficult and disappointing. Activated T cells are important in the pathogenesis of LP as indicated by the dermal lymphocytic infiltrate leading to keratinocyte destruction and lesion formation. Similar histologic findings are present in graft-versus-host disease. Since T cells are key players in the development of both disorders and mycophenolate mofetil has been successfully introduced in the treatment of graft-versus-host disease, we have examined the therapeutic potential of this agent in 3 patients suffering from disseminated and erosive LP. Mycophenolate mofetil was well tolerated and induced complete remission in 2 patients, and substantial improvement in the third patient. 相似文献
108.
109.
Kidney transplant in children weighing less than 15 kg: donor selection and technical considerations
Neipp M Offner G Lück R Latta K Strehlau J Schlitt HJ Ehrich JH Klempnauer J Nashan Br 《Transplantation》2002,73(3):409-416
BACKGROUND: Small children represent a challenging patient group in kidney transplantation (KTx). The aim of this study was to analyze patient and donor data influencing outcome in children that weighed <15 kg. METHODS: Sixty-eight kidneys were transplanted in 64 children that weighed <15 kg. In 44 cases, kidneys came from cadaveric donors (CAD) and in 24 cases from living-related donors (LRD). Grafts were placed transperitoneally via midline incision (n=16) or extraperitoneally to the iliac fossa (n=52). Vascular anastomoses were routinely performed to the aorta and vena cava even when the extraperitoneal approach was used. RESULTS: Vascular thrombosis was observed in two (3%), urinary leaks in five (7%), and stenosis in four (6%) patients. In six children receiving organs from adults to the iliac fossa, wound closure was performed using an absorbable mesh to avoid organ compression. Initial graft function occurred in 60 cases (88%). Frequency of initial graft function was significantly higher after KTx from LRD (100%) compared with CAD (82%). The 1-, 5-, and 10-year patient survival was 93%, 91%, and 91%, respectively, and the 1-, 5-, and 10-year graft survival was 92%, 85%, and 85%, respectively. There was no significant difference in patient and graft survival when KTx from LRD and CAD were compared. Within the CAD group, graft survival was improved using kidneys from donors >12 years compared with younger donors. CONCLUSION: Despite size discrepancy between recipients and grafts, KTx is feasible in children that weigh <15 kg by using an improved surgical technique even when adult organs are placed to the iliac fossa. 相似文献
110.
Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes 总被引:11,自引:0,他引:11
Graham J Hagopian WA Kockum I Li LS Sanjeevi CB Lowe RM Schaefer JB Zarghami M Day HL Landin-Olsson M Palmer JP Janer-Villanueva M Hood L Sundkvist G Lernmark A Breslow N Dahlquist G Blohmé G;Diabetes Incidence in Sweden Study Group;Swedish Childhood Diabetes Study Group 《Diabetes》2002,51(5):1346-1355
Age-dependent associations between type 1 diabetes risk genes HLA, INS VNTR, and CTLA-4 and autoantibodies to GAD65 (GADAs), ICA512/IA-2, insulin, and islet cells were determined by logistic regression analysis in 971 incident patients with type 1 diabetes and 702 control subjects aged 0-34 years. GADAs were associated with HLA-DQ2 in young but not in older patients (P = 0.009). Autoantibodies to insulin were negatively associated with age (P < 0.0001) but positively associated with DQ8 (P = 0.03) and with INS VNTR (P = 0.04), supporting possible immune tolerance induction. ICA512/IA-2 were negatively associated with age (P < 0.0001) and with DQ2 (P < 0.0001) but positively associated with DQ8 (P = 0.04). Males were more likely than females to be negative for GADA (P < 0.0001), autoantibodies to islet cells (P = 0.04), and all four autoantibody markers (P = 0.004). The CTLA-4 3' end microsatellite marker was not associated with any of the autoantibodies. We conclude that age and genetic factors such as HLA-DQ and INS VNTR need to be combined with islet autoantibody markers when evaluating the risk for type 1 diabetes development. 相似文献