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11.
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   
12.
BACKGROUND: The potential of hyperechogenic fetal bowel to act as a hallmark for prenatal cystic fibrosis screening in the general population is controversial. METHODS: Our goal was to evaluate the incidence of cystic fibrosis in 209 fetuses with hyperechogenic bowel diagnosed at routine ultrasonography and with no family history of cystic fibrosis. The diagnosis of cystic fibrosis was based on prenatal screening for the eight mutations most frequently observed in France (deltaF508, deltaI507, 1717-1G-->A, G542X, G551D, R553X, W1282X, N1303K) and at postnatal follow up. RESULTS: The overall incidence of cystic fibrosis was 7/209 (3.3%) which is 84 times the estimated risk of CF in the general population (112500). Of these seven cases, six were diagnosed prenatally based on DNA analysis (deltaF508/deltaF508, n=5; deltaF508/G542X, n=1). One case in which only one mutation had been recognised was diagnosed clinically after birth (deltaF508/unidentified mutation). Of the seven cases, none was diagnosed at 16-19 weeks, four at 16-24 weeks, and three after this. The incidence of heterozygous fetuses (15/209, 7%) was not significantly higher than the 5% expected in the general population. The mutations involved in these heterozygous cases were deltaF508 (n=13), G542X (n=1), and G551D (n=1). CONCLUSIONS: Screening for cystic fibrosis should be offered to families in which fetal hyperechogenic bowel is diagnosed at routine ultrasonography. This underlines the need to review genetic counselling in this situation where the fetus is the index case for a genetic disease.  相似文献   
13.
AIMS: To establish the prevalence of cyclooxygenase-2 (COX-2) expression in a large series of resected Barrett's adenocarcinoma and associated preneoplastic lesions and to correlate this expression with clinicopathological data and prognosis. METHODS: COX-2 expression was assessed by immunohistochemistry in resected surgical specimens of 66 Barrett's adenocarcinomas and 32 cases of Barrett's mucosa (with dysplasia in 17 cases). RESULTS: Epithelial expression of COX-2 protein was increased in Barrett's mucosa compared with normal oesophagus. Epithelial expression of COX-2 was found in 91% of Barrett's specialized mucosa negative for dysplasia, 94% of Barrett's mucosa with dysplasia, and 97% of Barrett's adenocarcinoma. COX-2 expression was significantly higher in the well-differentiated adenocarcinomas when compared with the poorly differentiated tumours. There was no significant correlation between COX-2 expression and the other pathological features of the tumours. Survival analysis showed no significant prognostic value for COX-2. CONCLUSION: Our results confirm up-regulation of COX-2 in Barrett's oesophagus-metaplastic and dysplastic-and in Barrett's adenocarcinoma. Increased COX-2 expression did not differ during the progression from Barrett's oesophagus negative for dysplasia to Barrett's adenocarcinoma and is related to adenocarcinoma whose histology is well differentiated. This suggests that enhanced expression of COX-2 may occur early during Barrett's-associated neoplastic transformation.  相似文献   
14.
Biomodulation of transcriptional factor NF-kappa B by ionizing radiation]   总被引:1,自引:0,他引:1  
NF-kappaB (Nuclear Factor-kappaB) was described for the first time in 1986 as a nuclear protein binding to the kappa immunoglobulin-light chain enhancer. Since then, NF-kappaB has emerged as an ubiquitous factor involved in the regulation of numerous important processes as diverse as immune and inflammatory responses, apoptosis and cell proliferation. These last two properties explain the implication of NF-kappaB in the tumorigenic process as well as the promise of a targeted therapeutic intervention. This review focuses on the current knowledge on NF-kappaB regulation and discusses the therapeutic potential of targeting NF-kappaB in cancer in particular during radiotherapy.  相似文献   
15.
BACKGROUND: The aim of this study was to determine the prognostic factors for patients with advanced stage, low malignant potential ovarian tumour (LMPOT). PATIENTS AND METHODS: A retrospective review of 80 patients with serous LMPOT and peritoneal implants treated at or referred to our institution was carried out. RESULTS: Sixty-five patients had non-invasive implants. Fifteen patients had invasive implants. Twenty-nine patients had stage II and 51 patients had stage III disease. Three patients died of evolutive invasive disease and four of complications of treatment. The only prognostic factor of progression to 'evolutive invasive disease' is the pathologic subtype of peritoneal implants. The 5-year rates of evolutive invasive disease in patients with non-invasive implants and invasive implants were 2% and 31%, respectively (P <0.002). CONCLUSIONS: In this series, the only prognostic factor for patients with advanced stage borderline tumour is the type of peritoneal implant. More patients died of the treatment's complications than of the disease itself. The patients' prognosis with non-invasive implants seems to be excellent, and conservative management could be discussed in younger patients.  相似文献   
16.
BACKGROUND: Unsafe delivery and overuse of injections can result in the spread of hepatitis B virus, hepatitis C virus, and HIV. The aim of the present survey was to estimate the frequency of safe injection practices in Burkina Faso. METHOD: Using the new standardized World Health Organization tool to assess injection practices, we selected 80 primary health facilities with a two-stage cluster sampling method, collected information using structured observations and provider interviews, and analyzed the data using Epi-Info software. RESULTS: We observed 116 injections in 52 facilities. In 50 facilities [96%; 95% confidence interval (CI) 85-99%] injections were given with a new, single-use syringe and needle. In 29 facilities (56%; 95% CI 36-74%), staff recapped needles using two hands. All 80 facilities visited had a stock in the community to provide new, single-use syringes and needles. In 61% (95% CI 54-79%) of facilities, staff reported needlestick injuries in the last 12 months. Used needles were discarded in open containers in 66 facilities (83%; 95% CI 55-96%) and observed in the surroundings of 46 facilities (57%; 95% CI 32-80%). CONCLUSIONS: In 2000, most of the health facilities in Burkina Faso were using sterile injection equipment. However, practices were still observed that could expose patients, health care workers, and communities to risks, and that required specific interventions.  相似文献   
17.
BACKGROUND: Epidermal growth factor receptor (EGFR) is overexpressed in many types of cancers, especially colorectal cancer (CRC), and seems to reflect more aggressive histological and clinical behaviors. The aim of this study was to evaluate EGFR immunohistochemical reactivity in CRC biopsies, and to analyze its relationship with various histological and clinical characteristics and survival. PATIENTS AND METHODS: A composite EGFR score, obtained by multiplying the grade (% positive cells) by the intensity of labeling (0-9) was used to define patients with low or high EGFR expression whose clinicopathological features were then compared. Univariate tests and multivariate Cox proportional hazards model were applied for data analysis. RESULTS: Tissue sections from 150 CRC patients with a median follow-up of 40 months were examined. Median patient age at diagnosis was 70 years (range 38-89 years). EGFR reactivity was positive for 143 patients (97%) and high for 118 (80%). According to multivariate analysis, EGFR overexpression was significantly associated with tumor stage, with a higher percentage of EGFR overexpression in T3 than T4 (P=0.003) and not with overall survival. CONCLUSIONS: EGFR was overexpressed in this CRC patient population and was significantly associated with TNM (tumor-node-metastasis) stage T3. In the context of a new therapeutic strategy using EGFR-targeted therapies, although EGFR remains a controversial prognostic factor, this expression-stage association may play a crucial role in a decision to initiate an adjuvant treatment.  相似文献   
18.
Traditionally, bone has been viewed as a relatively static tissue only fulfilling mechanical and scaffolding function. In the past decade however, this classical view of the bone has considerably evolved towards a more complex picture. It is now clear that the skeleton is not only a recipient for hormonal input but it is also an endocrine organ itself. Through the secretion of an osteoblast-derived molecule, osteocalcin, the skeleton regulates glucose homeostasis and male reproductive functions. When undercarboxylated, osteocalcin acts following its binding to a G-coupled receptor, Gprc6a, on pancreatic β cells to increase insulin secretion, on muscle and white adipose tissue to promote glucose homeostasis and on Leydig cells of the testis to favor testosterone biosynthesis. More recently, it was also shown that osteocalcin acts via a pancreas-bone-testis axis that regulates, independently of and in parallel to the hypothalamus–pituitary–testis axis, male reproductive functions by promoting testosterone biosynthesis. Lastly, in trying to expand the biological relevance of osteocalcin from mouse to human, it was shown that Gprc6a is a potential new susceptibility locus for primary testicular failure in humans. Altogether, these results shed new light on the importance of the endocrine role of the skeleton and also provide credence to the search for additional endocrine functions of this organ.  相似文献   
19.
Paraganglioma of the ampulla of Vater: a potentially malignant neoplasm   总被引:4,自引:0,他引:4  
Paragangliomas are rare tumours originating from neuroectodermic remnants and are usually considered as benign. We present two cases of paraganglioma of the ampulla of Vater that were treated surgically by pancreaticoduodenectomy. In one case, histopathology revealed malignant characteristics of the tumour with invasion of the pancreas and simultaneous duodenal lymph-node metastases. Both patients had a favourable outcome without disease recurrence at 40 and 44 months postoperatively. Only 21 cases of ampullary paraganglioma have been reported in the literature, 7 of them with malignant characteristics. In conclusion, paragangliomas of the ampulla of Vater have malignant potential. Surgical therapy of these tumours should not be limited to local resection, as disease recurrence and lymph node involvement have been reported. We propose that paragangliomas of the ampulla of Vater should be operated by cephalic pancreaticoduodenectomy, which allows long-term and disease-free survival.  相似文献   
20.
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