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71.
Sonia Raskovsky Emilio Rivas Delia Bernik Jorge Medina Diana Jerusalinsky 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1990,13(1-2):17-32
The modulation of the binding of muscarinic cholinergic receptor ligands by phosphatidylserine purified from bovine cerebral cortex (BC-PS) was examined in vitro and in vivo. The enrichment of bovine cerebral cortical synaptosomal membranes with BC-PS, using a fusion technique, produced a concentration-dependent decrease in the affinity (increase in K d ) of [3H]quinuclidinyl benzylate (3H-QNB) specific binding to muscarinic acetylcholine receptors (mAChR), without changes in their maximal number (Bmax). Similar results were observed when [3H]oxotremorine (3H-OXO) was used to label a high affinity subpopulation of mAChR. On the other hand, preincubation of BC-PS liposomes with synaptosomal membranes in a nonoptimum fusion condition (at pH 7.4) did not alter the binding properties of both radioligands. Fusion experiments using a pure phosphatidylserine preparation from spinal cord revealed a similar decrement in the affinity of3H-QNB specific binding. Five day’s intraperitoneal (i.p.) administration of 15 mg/kg of BC-PS liposomes in rats increased the maximal number of cerebral cortical binding sites for3H-OXO. Scatchard analysis revealed no changes in the apparent dissociation constant. This modification is selective in relation to the neural structure studied. Thus, BC-PS treatment did not modify3H-OXO binding in the hippocampal formation and cerebellum. In contrast, parallel experiments using the muscarinic antagonist3H-QNB showed no alteration in the binding properties of mAChR. Five day’s i.p. administration of 15 mg/kg/d of phosphatidylcholine from bovine cerebral cortex (BC-PC) liposomes produced quite similar results to those obtained with BC-PS. These results indicate that mAChR are under the modulatory action of phosphatidylserine (PS) and phosphatidylcholine (PC), and suggest that this endogenous phospholipids may play a regulatory role on the mAChR. The possible implications of these findings on the effects of PC or PS treatment in neurological disorders involving a decrease in central cholinergic functions are discussed. 相似文献
72.
The shelter experiences, employment history, income and social service needs utilization were examined among 124 emergency shelter users in Vancouver, British Columbia. Thirty-six (30.5%) reported this as their first experience with living in a shelter; the length of stay in the present shelter ranged from one to 90 days. Reasons for shelter use included: eviction from last place of residence, loss of job, or suffering from health problems rendering one unable to work. The highest unmet service needs were finding affordable housing and finding a job. This combination of scarcity of low-cost housing, health problems, and difficulty in finding employment have led to a situation where emergency shelters have become extended places of residence, a home to many.Sonia Acorn, RN, PhD is an Associate Professor at the School of Nursing, University of British Columbia, Vancouver, Canada.This research was funded by the Mr. and Mrs. P.A. Woodward's Foundation and the Vancouver Foundation. 相似文献
73.
74.
Friedman D Cuneo S Valenzano M Marinari GM Adami GF Gianetta E Traverso E Scopinaro N 《Obesity surgery》1995,5(3):308-313
Background: 239 pregnancies occurred in 1136 women who had undergone biliopancreatic diversion (BPD). Methods: There were
73 abortions, and 14 pregnancies are presently in their course. The 152 term pregnancies (six twins) occurred in 129 women
2-173 months (mean 42.7) after BPD. Mean age and current excess weight were 31.4 years (20-42) and 29.1% (-6.9-78.2), and
mean excess weight loss was 72.9% (30.4-110.5). Results: Mean weight gain during pregnancy was 6.2 kg (-21-25). In 32 patients
(21%), parenteral nutritional support was needed. In all the other patients (79%), the usual supplementations were given.
Of the newborns, 122 were delivered at term (84.7%) with a mean weight of 2842.4 g (1760-4600 g) and a mean length of 48.5
cm (43-59 cm), while the 22 preterm babies (15.3%) weighed 2151.1 g (1400-3850 g) and had a length of 44.6 cm (33-56 cm).
Forty infants (27.8%) were small for gestational age but 17 of them weighed more than 2500 g. Eleven twins (one abortion at
26th week) were also delivered, with a mean weight of 2088.6 g (1200-3100 g) and a mean length of 45.6 cm (35-50 cm). Delivery
was spontaneous in 85 instances (56%), while vacuum extractor was used in one, and 66 cesarean sections were performed. There
were two birth malformations, one infant died after surgery for meconium obstruction and two died from unknown causes. Of
the 129 women, 35 had been infertile before BPD. Conclusions: Disappearance of infertility and decrease of pregnancy risk
are to be considered among the beneficial effects of weight reduction following BPD. 相似文献
75.
Ancoli-Israel S Walsh JK Mangano RM Fujimori M 《Primary care companion to the Journal of clinical psychiatry》1999,1(4):114-120
BACKGROUND: Insomnia is a very common symptom, particularly in the elderly. Thus, all hypnotic medications should be carefully evaluated in the elderly population. Zaleplon, a new nonbenzodiazepine hypnotic with a short elimination half-life (approximately 1 hour), was evaluated in the current study. METHOD: This multicenter, randomized, placebo-controlled outpatient study evaluated the efficacy and safety of zaleplon, 5 and 10 mg, in elderly patients with insomnia (as defined by DSM-IV); zolpidem, 5 mg, was the active comparator. Sleep was assessed in 549 elderly patients (>/= 65 years old) by using morning questionnaires completed after each of 7 baseline nights during which placebo was given, 14 nights of double-blind treatment, and 7 nights of placebo after discontinuation of active treatment. RESULTS: Zaleplon, 10 mg, and zolpidem, 5 mg, significantly reduced sleep latency during both weeks of the study. Zaleplon, 5 mg, reduced sleep latency only during week 2. Sleep duration was increased with zolpidem, 5 mg, during weeks 1 and 2 and with zaleplon, 10 mg, during week 1. No clinically significant rebound insomnia was observed after discontinuation of treatment with zaleplon, whereas evidence of rebound effects was seen with zolpidem. There was no significant difference between either zaleplon dose and placebo in the frequency of any central nervous system adverse events. CONCLUSION: Zaleplon is effective in reducing latency to sleep without evidence of undesired effects in elderly patients with insomnia. 相似文献
76.
Widespread Horizontal Connections Arising from Layer 5/6 Border Inverted Cells in Rabbit Visual Cortex 总被引:1,自引:0,他引:1
Reblet C López-Medina A Gómez-Urquijo SM Bueno-López JL 《The European journal of neuroscience》1992,4(3):221-234
Herein we describe the inverted cells [defined as those projection neurons having a major dendritic shaft abpially oriented (Bueno-López et al., Eur. J. Neurosci. , 3, 415, 1991)] originating a unique set of cortical connections characterized by extraordinarily widespread horizontal distribution. Single and multiple injections of wheatgerm agglutinin - horseradish peroxidase were made in areas 17 and 18 and the resulting retrograde labelling in the cortex was analysed. The findings were assessed in independent control experiments in which Fluoro-Gold was used as retrograde tracer. Following single injections in area 17 several separate patches of labelled cells comprising layers 2–6 were consistently found in area 18. In addition to these associational cells a number of labelled cells appeared at the layer 5/6 border but were distributed over most of the tangential extent of the visual occipital cortex. This widespread pattern was particularly striking in brains after multiple injections. In these brains a conspicuous band of labelled cells at the 5/6 border radiated from the injection sites, making up an apparently continuous horizontal sheet that intersected the striate - extrastriate boundary and merged with the patches of labelled cells in area 18 and beyond. Most of the cells in the 5/6 border band were inverted cells (82%; n = 2081). Injections in area 18 failed to produce such a widespread set of labelled cells in area 17. The functional significance of these connections furnished by the 5/6 border inverted cells remains to be determined, but their distribution would allow for convergent/divergent binding interactions both intra-areally (within area 17) and inter-areally (from area 18 to area 17). 相似文献
77.
Lamberto Re Cinzia Corneli Emanuele Sturani Giancarlo Paolucci Francesca Rossini Olga Sonia León Gregorio Martínez Marica Bordicchia Quintilio Tomassetti 《Pharmacological research》2003,48(1):55-60
The St. John's Wort (Hypericum perforatum) extract (Hp) represents one of the most useful natural therapeutic agents in the treatment of moderate and mild depression. The antidepressant effects of Hp are different, by a molecular mechanism point of view, when compared to those of other antidepressant drugs and, we think, a further pharmacological characterization is needed. It is suggested that the neurochemical effects of Hp could be bind either to its activity on the uptake of some mediators in the central nervous system or to the inhibition of some enzymatic activity at the receptor level. The present study carried out with the loose patch clamp (LPC) in the mouse neuromuscular junction, indicates a potentiation of the acetylcholine (ACh) action at the mouse neuromuscular junction. The spontaneous release of ACh was unaffected by Hp indicating that neither presynaptic nor postsynaptic function are modified by Hp. Indeed, both the frequency and the amplitude of the miniature end-plate currents (mepcs) were unmodified by Hp. Furthermore, the mepcs decay time (tau), i.e. the apparent cholinergic channel life time, was significantly increased after Hp treatment. The other parameter affected was the amplitude of the evoked end-plate currents (epcs) which was constantly and in a dose dependent manner increased by Hp. These findings suggest a possible action of Hp on the acetylcholinesterase (AChE) in terms of a reduction of the degradation rate of ACh. 相似文献
78.
Gianni Sava Sonia Zorzet Claudia Turrin Francesca Vita MariaRosa Soranzo Giuliano Zabucchi Moreno Cocchietto Alberta Bergamo Stefano DiGiovine Gabriella Pezzoni Luigi Sartor Spiridione Garbisa 《Clinical cancer research》2003,9(5):1898-1905
NAMI-A is a ruthenium complex endowed with a selective effect on lung metastases of solid metastasizing tumors. The aim of this study is to provide evidence that NAMI-A's effect is based on the selective sensitivity of the metastasis cell, as compared with other tumor cells, and to show that lungs represent a privileged site for the antimetastatic effects. The transplantation of Lewis lung carcinoma cells, harvested from the primary tumor of mice treated with 35 mg/kg/day NAMI-A for six consecutive days, a dose active on metastases, shows no change in primary tumor take and growth but a significant reduction in formation of spontaneous lung metastases. Transmission electron microscopy examination of lungs and kidney shows NAMI-A to selectively bind collagen of the lung extracellular matrix and also type IV collagen of the basement membrane of kidney glomeruli. The half lifetime of NAMI-A elimination from the lungs is longer than for liver, kidney, and primary tumor. NAMI-A bound to collagen is active on tumor cells as shown in vitro by an invasion test, using a modified Boyden chamber and Matrigel, and it inhibits the matrix metallo-proteinases MMP-2 and MMP-9 at micromolar concentrations, as shown in vitro by a zimography test. These data show NAMI-A to significantly affect tumor cells with metastatic ability. Binding to collagen allows NAMI-A to exert its selective activity on metastatic cells during dissemination and particularly in the lungs. These data also stress the wide spectrum of daily doses and treatment schedules at which NAMI-A is active against metastases. 相似文献
79.
Gerardo Zanetta Consultant Stefania Chiari Consultant Sonia Rota Registrar Giorgio Bratina Professor rea Maneo Registrar Valter Torri Medical Statistician Costantino Mangioni Professor 《BJOG : an international journal of obstetrics and gynaecology》1997,104(9):1030-1035
Objective To assess the results of a policy of tailored conservative surgical management for young women with stage I ovarian carcinomas.
Design Retrospective study.
Participants Ninety-nine women aged 40 years or younger who underwent either primary surgery in our department or were referred after primary surgery performed elsewhere.
Methods Of the 99 women in our study, 56 underwent fertility-sparing surgery and 43 more radical surgery. Minimal requirements for conservative management were adequate staging and complete information about the therapeutic options. Factors important in the choice of the treatment were, age, wish to preserve fertility, histologic type and grade, and the stage of the tumour.
Results Conservative treatment was conducted in 84% of nulliparous and in 33% of parous women; 62% of grade 1 tumours, 48% of grade 2, and 50% of grade 3 were treated conservatively. With a median follow up of seven years, we observed five recurrences (9%) of carcinoma in women treated conservatively and five (12%) in those treated more radically. Two women (one in each treatment arm) were saved after recurrence. Two recurrences after conservative surgery involved the residual ovary (3.6%). Two women developed borderline tumour in the contralateral ovary and both were treated by surgery.
Conclusion After adequate staging and accurate information is given to the patient, conservative treatment may be safe in some women with early ovarian cancer. The risk of recurrence in the contralateral ovary is low. Conservative surgery may be also considered in some Stage I grade 3 tumours and in some women with stage IC tumours. 相似文献
Design Retrospective study.
Participants Ninety-nine women aged 40 years or younger who underwent either primary surgery in our department or were referred after primary surgery performed elsewhere.
Methods Of the 99 women in our study, 56 underwent fertility-sparing surgery and 43 more radical surgery. Minimal requirements for conservative management were adequate staging and complete information about the therapeutic options. Factors important in the choice of the treatment were, age, wish to preserve fertility, histologic type and grade, and the stage of the tumour.
Results Conservative treatment was conducted in 84% of nulliparous and in 33% of parous women; 62% of grade 1 tumours, 48% of grade 2, and 50% of grade 3 were treated conservatively. With a median follow up of seven years, we observed five recurrences (9%) of carcinoma in women treated conservatively and five (12%) in those treated more radically. Two women (one in each treatment arm) were saved after recurrence. Two recurrences after conservative surgery involved the residual ovary (3.6%). Two women developed borderline tumour in the contralateral ovary and both were treated by surgery.
Conclusion After adequate staging and accurate information is given to the patient, conservative treatment may be safe in some women with early ovarian cancer. The risk of recurrence in the contralateral ovary is low. Conservative surgery may be also considered in some Stage I grade 3 tumours and in some women with stage IC tumours. 相似文献
80.
Fernando Chaves Jesus García-Martínez Sonia de Miguel Francisca Sanz Joaquín R Otero 《Infection control and hospital epidemiology》2005,26(2):150-156
OBJECTIVES: To describe the relative proportions of nosocomial and community-onset Staphylococcus aureus bacteremia at our institution and the epidemiologic characteristics and clonal diversity of S. aureus isolates, as determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance patterns. DESIGN: Retrospective cohort study of all cases of S. aureus bacteremia between October 2001 and October 2002. SETTING: A 1300-bed, tertiary-care hospital. RESULTS: One hundred sixty-two unique episodes of S. aureus bacteremia were identified. Forty-three cases (26.5%) were caused by methicillin-resistant S. aureus (MRSA). Most cases of S. aureus bacteremia, whether MRSA or methicillin susceptible (MSSA), were nosocomial in origin (77.2%) or were otherwise associated with the healthcare system (16%). Only 11 (6.8%) of the cases (all MSSA) were strictly community acquired. Thirty-five unique macrorestriction patterns were identified among the 154 isolates that were typed by PFGE. Four major genotypes were defined among the isolates of MRSA, with 36 (85.7%) represented by a single PFGE type. Of the isolates within this major clone, all (100%) were ciprofloxacin resistant and 77.8% were erythromycin resistant. In contrast, the 112 isolates of MSSA comprised 31 different PFGE types, 3 of which represented 42.9% of all MSSA isolates and were associated with both nosocomial and community-onset bacteremia. CONCLUSIONS: Most cases of S. aureus bacteremia in our healthcare region are nosocomial in origin or are acquired through contact with the healthcare system and are thus potentially preventable. To preclude dissemination of pathogenic clones, it is therefore necessary to redouble preventive measures in both the hospital and the community. 相似文献