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41.
The lamina terminalis (LT) contains three main regions, namely the subfornical organ (SFO), the median preoptic nucleus (MnPO) and the vascular organ of the LT (OVLT). Although LT is recognized of paramount importance in the regulation of hydromineral homeostasis, identity of the neurocircuits interconnecting the SFO and OVLT to the MnPO is not known. Furthermore, the phenotype of neuronal populations activated during acute hydromineral challenge is not yet determined. By using the high cellular resolution of the in situ hybridization histochemistry (ISHH), we investigated whether a furosemide-induced fluid and electrolyte depletion might modify both putative GABAergic and glutamatergic systems within the LT. We show that acute furosemide treatment (4 h) significantly reduced the expression of GAD67 mRNA, the active holoenzyme predictive of GABA synthesis, within the SFO. A strong tendency toward a reduction of GAD67 signal was also observed in the OVLT and MnPO. The hydromineral challenge did not alter the expression of GAD65 and type 2 vesicular glutamate transporter (vGlut2) mRNA in all the structures of the LT. Furosemide treatment was associated with a reduction in the population of GAD67-containing neurons in the periphery of the SFO and dorsal part of the MnPO. Contrastingly, GAD65-containing cells were shown to be increased in the OVLT and no change was observed for the vGlut2-containing neurons in the whole LT. By combining ISHH with immunohistochemistry (Fos immunoreactivity), we report that furosemide-induced water and sodium depletion did essentially recruit a glutamatergic network throughout the LT, although GABAergic neurons were specifically activated in the ring of the SFO and in the OVLT. The MnPO, the region of the LT that is considered as being an integrative area for sensory inputs arising from the SFO and OVLT, showed exclusive activation of excitatory neuronal populations. Taken together these results suggest that acute water and Na(+) depletion diminish the efficacy of the GABAergic system and mainly activates excitatory neuronal pathways in the regions of the LT. 相似文献
42.
Using a subtractlve strategy, we have cloned an activation-relatedgene from a human B cell cDNA library. Sequence analysis revealedthat this gene was identical to H12.3, a gene belonging to anexpanding family of guanlne nucleotlde-blndlng protein ßsubunlts. The expression of H12.3 was induclble in the latephase of mltogen-stlmulated T and B cells. In T cells, IL-2and IL-4 by themselves had no direct effect on the expressionof H12.3, but they could augment the level of steady-state H12.3mRNA stimulated by phytohemagglutlnln. On the other hand, IFN-and IL-6 had no obvious effect on the expression in B cellswith or without Staphytococcus aureus Cowan l-stlmulatlon. CyclosporinA, a strong immunosuppressant, Inhibited the mltogen-stlmulatedexpression of H12.3, but rapamycin, another such agent, didnot. In synchronized Jurkat cells, the expression of H12.3 hadno cell cycle-dependent decrease in S and G2/M phase, whilecyclin E, which controls the progression of the cell cycle unlate G1 phase, did show a periodic expression pattern. The resultssuggest that H12.3 might be involved in regulation of lymphocyteactivation. 相似文献
43.
Optimization of an elispot assay to detect cytomegalovirus-specific CD8+ T lymphocytes 总被引:1,自引:0,他引:1
Godard B Gazagne A Gey A Baptiste M Vingert B Pegaz-Fiornet B Strompf L Fridman WH Glotz D Tartour E 《Human immunology》2004,65(11):1307-1318
Various arguments suggest that CD8+ T lymphocytes play a major role in the control of cytomegalovirus (CMV) infection. The detection of CMV-specific CD8+ T cells may therefore provide additional information about CMV virus detection to predict the risk of development of CMV disease, especially in immunodepressed transplant recipients. We compared and tested various experimental conditions to optimize an enzyme-linked immunospot assay (Elispot) assay for the detection of CMV-specific CD8+ T lymphocytes. The indirect Elispot assay with one six-day in vitro sensitization step was found to be the most sensitive method to detect CMV-specific CD8+ T cells compared to direct Elispot with unfractionated peripheral blood mononuclear cells or purified CD8+ T cells. We showed that low doses of interleukin-2 during the in vitro culture enhanced the sensitivity of this test, and tetramer staining was performed to verify the high efficiency of this in vitro stimulation step. We directly loaded the specific CMV peptide during the Elispot assay and demonstrated that the use of T2 cells did not improve its sensitivity. Elispot for the detection of interferon-gamma appears to be more sensitive and reliable than measurement of tumor necrosis factor alpha or granzyme B. This technique was successfully applied to detect CMV-specific CD8+ T cells in human leukocyte antigen A2 (HLA-A2) and HLA-B7 healthy patients and in one lymphopenic post-transplant patient with positive CMV serology. This highly sensitive test may be a useful tool to assess T-cell immunity directed against CMV in immunodepressed patients. 相似文献
44.
Cytogenetic analysis of a mesenchymal hamartoma of the liver 总被引:4,自引:0,他引:4
F Speleman V De Telder K R De Potter P Dal Cin S Van Daele Y Benoit J G Leroy H Van den Berghe 《Cancer Genetics and Cytogenetics》1989,40(1):29-32
Cytogenetic analysis of a mesenchymal hamartoma of the liver in a 3-year-old child revealed a balanced translocation between chromosomes 15 and 19 as the sole chromosome change. 相似文献
45.
B Charpentier P Lang C Hiesse P Fixy O Lantz J Bellamy G Benoit D Fries 《Annales de médecine interne》1987,138(5):366-368
An increased incidence of Kaposi's sarcoma is well known in renal transplant recipients in whom it may represent up to 3 p. 100 of all de novo tumours. This sarcoma has a close relationship with the potential oncogenicity of the cytomegalovirus (CMV) and with chronic immunological deficiency. Anti-CMV immunity is based on the integrity of cytotoxic cellular functions such as those of cytotoxic T lymphocytes (CTL), "natural killers" cells, and K cells which function in the antibody-dependent cell cytotoxicity (ADCC) system. Two cases of Kaposi's sarcoma were observed out of a total of 700 renal transplant recipients; they underwent the following investigations: lymphocyte sub-group counts by murine monoclonal antibodies, lymphocyte proliferation to lectins and allogenic cells, NK activity and generation of specific auxiliary and cytotoxic anti-CMV cells. Both cases of Kaposi's sarcoma were seropositive for CMV and seronegative for LAV. In one case, an abnormal number of peripheral OKT9 + lymphocytes (normally a thymocytic marker) was observed with small numbers of OKT4/OKT8, a reduced proliferative response to mitogens and allogenic cells. All these in vitro changes persisted despite reduction of immunosuppressive therapy and clinical improvement. A clinical and biological cure was only obtained after withdrawal of immunosuppressive therapy and return to haemodialysis. In the second case of Kaposi's sarcoma, the initial biochemical changes were minimal and a clinical cure was obtained by decreasing the immunosuppressive therapy. These two cases illustrate the complex dysregulation of the immune system in Kaposi's sarcoma. 相似文献
46.
This article analyzes a series of 302 female patients prone to cystitis. The fact that these women were seen in a urological crenotherapy center highlights the very evolutive nature of the disease. The high rate of E coli present in the urine should be noted. Most of the women had a normal intravenous urogram and a normal endoscopy. The "classic" causes are rarely responsible for attacks of cystitis, but sexual intercourse and pregnancy seem to play a part. Several of the women took estroprogestative pills, or wore an intra-uterine device. The rate of bowel symptomatology-colopathy or constipation--should be noted. The article assesses the evolution of cystitis before and after crenotherapy at La Preste. 相似文献
47.
David J. Stewart Brien Benoit Michael T. Richard Herman Hugenholtz Jean Dennery Neville Russell Eric Peterson Zvonimir Grahovac Garry Belanger Jean A. Maroun Vincent Young 《Journal of neuro-oncology》1984,2(1):53-58
Summary Twenty-six adult patients with astrocytomas were treated with BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) 180–240 mg/m2 1.V. every 6–9 weeks, with metronidazole 1.5 g/m2 p. o. 12 h and 1 h before BCNU and again 6 h and 24 h after BCNU. Of twenty-two evaluable patients, 9 (41%) responded with evidence of reduced tumor size on CT scan, 3 (14%) stabilized and 10 (45%) failed. Patients with no prior chemotherapy or radiotherapy, good performance. status, low grade tumors, and age 50 years had the highest response rates, although differences were not statistically significant. Median survival and duration of response have not been reached with a median follow-up time of ten months. Hematological toxicity was dose-limiting and was probably not augmented by the metronidazole. There was one death from infection that was possibly drug-related. Gastrointestinal toxicity was substantial, and was probably increased by the metronidazole.While the combination of BCNU and metronidazole were tolerable, the response rate seen was no higher than that noted for BCNU alone, and further studies using this dose-schedule are not recommended in astrocytomas.Presented at the 13th International Congress of Chemotherapy, Vienna Austria, August 1983. 相似文献
48.
F. M. Benoit G. L. LeBel D. T. Williams 《International archives of occupational and environmental health》1984,53(3):261-267
Summary In response to the question: Are datascreen terminals a source of increased PCB concentrations in the working atmosphere? a study of PCB emissions from video display terminals (VDT) was undertaken. Emissions of 2.4 to 8.1 ng PCB/h were observed from VDT located in a building (1) where the mean PCB level in the air was 46 ng PCB/m3 during the test period, whereas no PCB emissions were detected from VDT located in a building (2) where no PCB could be detected in the ambient air. However, both the air and the VDT from building 2 were found to be contaminated with polycyclic aromatic hydrocarbons. We conclude that the observed PCB emissions from VDT are the result of the vapourization of PCB deposited onto the VDT from the PCB contaminated air and do not originate from the electrical components of the VDT. 相似文献
49.
50.
Natacha Martin Anne Bergougnoux Nesrine Baatallah Benoit Chevalier Jessica Varilh David Baux Bruno Costes Pascale Fanen Caroline Raynal Isabelle Sermet-Gaudelus Emmanuelle Girodon Magali Taulan-Cadars Alexandre Hinzpeter 《Journal of cystic fibrosis》2021,20(3):464-472
BackgroundMinigenes and in silico prediction tools are commonly used to assess the impact on splicing of CFTR variants. Exon skipping is often neglected though it could impact the efficacy of targeted therapies. The aim of the study was to identify exon skipping associated with CFTR variants and to evaluate in silico predictions of seven freely available software.MethodsCFTR basal exon skipping was evaluated on endogenous mRNA extracted from non-CF nasal cells and on two CFTR minigene banks. In silico tools and minigene systems were used to evaluate the impact of CFTR exonic variants on exon skipping.ResultsData showed that out of 65 CFTR variants tested, 26 enhanced exon skipping and that in silico prediction efficacy was of 50%-66%. Some in silico tools presented predictions with a bias towards the occurrence of splicing events while others presented a bias towards the absence of splicing events (non-detection including true negatives and false negatives). Classification of exons depending on their basal exon skipping level increased prediction rates up to 80%.ConclusionThis study indicates that taking basal exon skipping into account could orientate the choice of the in silico tools to improve prediction rates. It also highlights the need to validate effects using in vitro assays or mRNA studies in patients. Eventually, it shows that variant-guided therapy should also target exon skipping associated with variants. 相似文献