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Sara Boulaïch Annie Daszuta Michel Geffard Olivier Bosler 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,101(3):353-364
We have previously reported that a cell suspension from the rostral part of the embryonic raphe grafted to the basal hypothalamus of 5,7-dihydroxytryptamine-denervated rats produced incomplete serotonin (5-HT) re-innervation of the suprachiasmatic nucleus (SCN) as opposed to hyper-innervation of the supraoptic nucleus (SON). We took advantage of this experimental model to investigate whether the graft-derived, 5-HT fibres retained normal ultrastructural features, and, particularly, a normal density of synaptic junctions, irrespective of the extent of target re-innervation. The intrinsic features of immunostained, graft-derived 5-HT axonal varicosities in both the SCN (ventral portion) and the SON were essentially similar to those exhibited by the respective endogenous innervation. Analysis of well-preserved varicosities in uninterrupted series of thin sections allowed us to evaluate directly the proportions of junctional to non-junctional 5-HT varicosities in both regions. Synaptic incidences were also remarkably conserved after grafting (45.5% in the SCN versus 38.5% in the SON; 48% and 38% in normal rats, respectively). Synapses were primarily reestablished on dendritic shafts, which also were identified as the major post-synaptic targets of the normal 5-HT innervations. We noted, however, a tendency toward increased numbers of symmetrical versus asymmetrical synapses in both the SCN and SON of grafted rats. Thus, irrespective of whether hypo-or hyper-innervation patterns developed post-grafting, the transplanted 5-HT neurons essentially retained normal ultrastructural features in their target territories, with a normal incidence of synaptic junctions. The data provide further support to the hypothesis that the innervation territory is the major determinant of the frequency with which ingrowing 5-HT fibres make synaptic junctions. 相似文献
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Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency 总被引:1,自引:0,他引:1
Hong YS; Kerr DS; Craigen WJ; Tan J; Pan Y; Lusk M; Patel MS 《Human molecular genetics》1996,5(12):1925-1930
An infant girl with elevated blood lactate, pyruvate, and plasma
branched-chain amino acids was diagnosed with dihydrolipoamide
dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4)
deficiency. Activities of the pyruvate dehydrogenase complex and E3 from
patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in
cultured skin fibroblasts, respectively. Western blot analysis demonstrated
that the amount of E3 protein in fibroblasts from the patient and her
father was about half of controls, while Northern blot analysis showed
normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs
from the patient revealed two mutations in separate alleles. One is a
single base insertion of an extra adenine in the last codon of the leader
peptide sequence (TAC-->TAAC) leading to a nonsense mutation which
results in the premature termination of the precursor E3 polypeptide
(Y35X). The other is a missense mutation due to substitution of guanine for
adenine, causing an Arg-->Gly substitution at amino acid 460 of the
mature protein (R460G) which triggers the loss of E3 activity probably by
structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the
parents demonstrated that the nonsense mutation was inherited from the
father and the missense mutation was inherited from the mother.
相似文献
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Vuillet J Kerkerian-Le Goff L Kachidian P Dusticier G Bosler O Nieoullon A 《The European journal of neuroscience》1990,2(8):672-681
Dual labelling methods were applied to localize simultaneously neuropeptide Y (NPY) and glutamate decarboxylase (GAD) immunoreactivities on ultrathin sections of the rat caudate-putamen (CP). By means of a double peroxidase-anti-peroxidase technique, using 3,3'-diaminobenzidine and benzidine dihydrochloride as chromogens in animals with no colchicine pretreatment, GAD immunoreactivity was found to be present in terminals only whereas NPY immunoreactivity was detected in neurons displaying the features of aspiny type cells and processes. With this approach, we observed numerous synaptic associations of the symmetrical type between GAD-immunoreactive (-Ir) axonal boutons and NPY-Ir cell bodies and dendrites. By combining immunoperoxidase and radioimmunocytochemical labelling in animals pretreated with colchicine, NPY was again detected in a single population of aspiny type neurons whereas GAD immunoreactivity was observed in neurons which could be classified as aspiny and spiny on the basis of their ultrastructural characteristics. All the cells of the aspiny type displaying clear-cut NPY immunoreactivity were also found to be GAD-positive. Some other neurons of both the aspiny and the spiny type were found to be immunoreactive to GAD alone. GAD/NPY dually labelled terminals were also observed and some axo-axonic appositions between GAD- and NPY-Ir terminals were also detected. All in all, these data show that NPY aspiny type neurons of the rat CP receive GABAergic afferents and provide morphological support for two hypotheses: that NPY is co-localized with GABA in some cell bodies, dendrites and axons, and that presynaptic interactions may occur between NPY and GABAergic neuronal systems. 相似文献
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Bacterial meningitis in infants: sonographic findings 总被引:1,自引:0,他引:1
A retrospective study was performed on 78 patients (newborn to 2 years old) with clinically proved bacterial meningitis. Sonograms were obtained during the acute illness and medical records were reviewed. The spectrum of sonographic features of meningitis included normal scans (30 patients), ventriculomegaly (11 patients), echogenic sulci (31 patients), extra-axial fluid collections (26 patients), abnormal parenchymal echogenicity (9 patients), evidence of ventriculitis (5 patients), and brain abscess (1 patient). In 46 patients, correlation between the sonographic findings and neurologic outcome on clinical follow-up (6 months to 4 years) was made. Findings of abnormal parenchymal echogenicity and/or moderate-to-marked ventriculomegaly were associated with significant neurologic sequelae; however, echogenic sulci and small extra-axial fluid collections did not appear to have any prognostic significance. Twenty-nine of the 78 patients had sonography without clinical indication of complications of meningitis, and in no patient was a significant abnormality found. Our study suggests that sonography is indicated only when there is clinical suspicion of complications. 相似文献
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Sireesha Koneru FRACS Mifanwy M. Reece MPhil FRACS Dulani Goonawardhana BMed MD Pierre H. Chapuis DS FRACS Krishanth Naidu FRACS Kheng-Seong Ng PhD FRACS Matthew J. F. X. Rickard MMed Dip Paed FRACS 《ANZ journal of surgery》2023,93(6):1646-1651
Backgrounds
Surgery remains mainstay management for colon cancer. Post-operative anastomotic leak (AL) carries significant morbidity and mortality. Rates of, and risk factors associated with AL following right hemicolectomy remain poorly documented across Australia and New Zealand. This study examines the Bowel Cancer Outcomes Registry (BCOR) to address this.Methods
A retrospective cohort study was undertaken of consecutive BCOR-registered right hemicolectomy patients undergoing resection for colon cancer (2007–2021). The primary outcome measure was AL incidence. Clinicopathological data were extracted from the BCOR. Factors associated with AL and primary anastomosis were identified using logistic regression. AL-rate trends were assessed by linear regression.Results
Of 13 512 patients who had a right hemicolectomy (45.2% male, mean age 72.5 years, SD 12.1), 258 (2.0%) had an AL. On multivariate analysis, male sex (OR 1.33; 95% CI 1.03–1.71) and emergency surgery (OR 1.41; 95% CI 1.04–1.92) were associated with AL. Private health insurance status (OR 0.66; 95% CI 0.50–0.88) and minimally-invasive surgery (OR 0.61; 95% CI 0.47–0.79) were protective for AL. Anastomotic technique (handsewn versus stapled) was not associated with AL (P = 0.84). Patients with higher ASA status (OR 0.47; 95% CI 0.39–0.58), advanced tumour stage (OR 0.56; 95% CI 0.50–0.63), and emergency surgery (OR 0.16; 95% CI 0.13–0.20) were less likely to have a primary anastomosis. AL-rate and year of surgery showed no association (P = 0.521).Conclusion
The AL rate in Australia and New Zealand following right hemicolectomy is consistent with the published literature and was stable throughout the study period. Sex, emergency surgery, insurance status, and minimally invasive surgery are associated with AL incidence. 相似文献10.
DS Keller RN Tahilramani JR Flores-Gonzalez S. Ibarra EM Haas 《Surgical endoscopy》2016,30(6):2192-2198