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11.
Paul R Gard Pauline Daw Zhila Sayyad Mashhour Paula Tran 《Journal of the renin-angiotensin-aldosterone system》2007,8(3):133-138
INTRODUCTION: Angiotensin (Ang) IV enhances learning and memory in rats but there are strain differences in its effects in mice. Oxytocin (OT) also influences learning and memory in rats and mice and, in the light of the proposed effects of Ang IV on oxytocinase, the hypothesis that the effects of Ang IV on cognition in mice involve OT was tested. MATERIALS AND METHODS: The effects of Ang IV and OT, alone and combined, were determined in rat isolated uterine smooth muscle and in object recognition and forced swim tests in BKW mice. RESULTS: Ang potentiated the contractile effects of OT in the uterus. Neither peptide had any effect on object recognition nor locomotor activity. Ang IV had no effect in the forced swim test but abolished the effects of OT. CONCLUSIONS: Ang IV influences the actions of OT in vitro and in vivo, possibly by inhibition of oxytocinase, but the lack of effect of Ang IV on object recognition in BKW mice is unlikely to be a consequence of a deficiency endogenous OT. Unlike OT, Ang IV alone has no effect on learned helplessness in the forced swim test, an effect often used to predict potential antidepressant efficacy in humans. 相似文献
12.
Fix Joseph A. Alexander Jose Cortese Margot Engle Karen Leppert Paula Repta A. J. 《Pharmaceutical research》1990,7(4):384-387
Short-chain alkyl esters of L-dopa were administered to rats and mice via oral and rectal routes. Plasma L-dopa esters and L-dopa were determined in the systemic and portal circulation by HPLC. A comparison of isopropyl, butyl, and 4-hydroxybutyl esters of L-dopa demonstrated significantly higher levels of the esters in both systemic and portal blood samples following rectal administration than following oral administration. In most cases, oral administration resulted in nondetectable (<0.01 µg/ml) levels of the esters in plasma. Correspondingly, the plasma levels of L-dopa itself were consistently higher following rectal administration. At very high oral doses (500 mg L-dopa equivalents/kg body weight), systemic plasma levels of the butyl ester could be detected (1.25 µg/ml at 10 min), which might indicate saturation of the esterase activity of the small intestine. These studies indicate that the systemic availability of L-dopa from short-chain alkyl esters of L-dopa may be best optimized by rectal administration, which avoids the relatively high esterase activity characteristic of the small intestine. 相似文献
13.
Effect of a glutamine-supplemented enteral diet on methotrexate-induced enterocolitis 总被引:15,自引:0,他引:15
A D Fox S A Kripke J De Paula J M Berman R G Settle J L Rombeau 《JPEN. Journal of parenteral and enteral nutrition》1988,12(4):325-331
Administration of an elemental diet to rats given methotrexate (MTX), 20 mg/kg intraperitoneally (ip), results in 100% mortality from severe enterocolitis. Previous studies indicate that glutamine (GLN), which is not present in elemental diets, is the preferred oxidative substrate for the gut and may facilitate intestinal recovery after injury. This study investigated the effects of a glutamine-supplemented elemental diet (GLN-ED) on nutritional status, intestinal morphometry, bacterial translocation and survival in this lethal model of intestinal injury. Three experiments were performed. In the first experiment, rats received an intragastric elemental diet supplemented with either 2% GLN or an equivalent amount of glycine (Control). After 4 days animals received either MTX, 20 mg/kg ip, or saline ip and were killed 3 days later. The GLN-ED resulted in significantly decreased weight loss, improved nitrogen retention, and increased mucosal weight, protein, and DNA content of the jejunum and colon. In the second experiment rats were assigned to diet as in the first experiment, but all animals received MTX. Control diet animals died within 120 hrs of MTX administration. The GLN-ED group had significantly longer survival time and decreased mortality. In the third experiment animals were assigned to diet and MTX as in the first experiment. Ninety-six hrs later aortic blood cultures revealed enteric bacteremia in animals administered MTX. GLN-ED resulted in a significant reduction in the incidence of bacteremia. These experiments showed that a GLN-ED significantly improved nutritional status, decreased intestinal injury, decreased bacterial translocation, and resulted in improved survival in a lethal model of enterocolitis. 相似文献
14.
Detecting pediatric autoimmune neuropsychiatric disorders associated with streptococcus in children with obsessive-compulsive disorder and tics. 总被引:6,自引:0,他引:6
Tanya K Murphy Muhammad Sajid Ohel Soto Nathan Shapira Paula Edge Mark Yang Mark H Lewis Wayne K Goodman 《Neuropsychopharmacology》2004,55(1):61-68
BACKGROUND: A subgroup of children with obsessive-compulsive and tic disorders are proposed to have an infectious trigger. The purpose of this study was to investigate the relationship between group A streptococcal titers and symptom fluctuations in children with a clinical course resembling that described for pediatric autoimmune neuropsychiatric disorders associated with streptococcus. METHODS: Twenty-five children with obsessive-compulsive disorder and/or tic disorder were evaluated for neuropsychiatric severity and group A streptococcal antibody titers (streptolysin O, deoxyribonuclease B, and carbohydrate A) at 6-week intervals for > or = six consecutive evaluations (total visits=277). RESULTS: Children with large symptom fluctuations (n=15) were compared with children without dramatic fluctuations (n=10). Co-movements of obsessive-compulsive/tic severity and group A streptococcal antibodies were assessed. In subjects with large symptom changes, positive correlations were found between streptococcal titers and obsessive-compulsive severity rating changes (p=.0130). These subjects were also more likely to have elevated group A streptococcal titers during the majority of observations (p=.001). Tic symptom exacerbations occurred more often in the fall/winter months than spring/summer months (p=.03). CONCLUSIONS: Patients with marked obsessive-compulsive/tic symptom changes may be characterized by streptococcal titer elevations and exhibit evidence of seasonal tic exacerbations. 相似文献
15.
在了解及处理坚持用药的情况较差时,医生往往遇到很多困难。困扰医生的一个主要问题是,如何护理患有急性或危及生命的疾病而不能长期坚持治疗的儿童。对医生来说,更难的是如何了解父母何时不能为子女提供适当的护理。近30%~70%的患慢性疾病者,因为治疗时间长、服用的药物种类多及症状时有缓解而不能坚持用药。临床经验表明,患有慢性疾病,如囊性纤维化、癫痫、哮喘、糖尿病患者坚持用药的情况较差。 相似文献
16.
Luiz H Castro Luiz K Ferreira Leandro R Teles Carmen L Jorge Paula R Arantes Carla R Ono Carla C Adda Rosa F Valerio 《Seizure》2007,16(1):50-58
PURPOSE: Hypothalamic hamartoma (HH) related epilepsy presents with gelastic seizures (GS), other seizure types and cognitive deterioration. Although seizure origin in GS has been well established, non-GS are poorly characterized. Their relationship with the HH and cognitive deterioration remains poorly understood. We analyzed seizure type, spread pattern in non-GS and their relationship with the epileptic syndrome in HH. METHODS: We documented all current seizure types in six adult patients with HH-epilepsy with video-EEG monitoring, characterized clinical-electrographic features of gelastic and non-gelastic seizures and correlated these findings with cognitive profile, as well as MRI and ictal SPECT data. RESULTS: Only four seizure types were seen: GS, complex partial (CPS), tonic seizures (TS) and secondarily generalized tonic-clonic seizures (sGTC). An individual patient presented either CPS or TS, but not both. GS progressed to CPS or TS, but not both. Ictal patterns in GS/TS and in GS/CPS overlapped, suggesting ictal spread from the HH to other cortical regions. Ictal SPECT patterns also showed GS/TS overlap. Patients with GS-CPS presented a more benign profile with preserved cognition and clinical-EEG features of temporal lobe epilepsy. Patients with GS-TS had clinical-EEG features of symptomatic generalized epilepsy, including mental deterioration. CONCLUSIONS: Video-EEG and ictal SPECT findings suggest that all seizures in HH-related epilepsy originate in the HH, with two clinical epilepsy syndromes: one resembling temporal lobe epilepsy and a more catastrophic syndrome, with features of a symptomatic generalized epilepsy. The epilepsy syndrome may be determined by HH size or by seizure spread pattern. 相似文献
17.
Perry D. Cohen Linda Herman Sheryl Jedlinski Peggy Willocks Paula Wittekind 《Neurotherapeutics》2007,4(3):537-544
A patient-centered paradigm for clinical research and medical care is presented as a solution to the problem of declining
innovation and increasing costs and development time in the pipeline for new therapies. Fundamental differences in values
and motivations among scientists, clinicians, industry sponsor, and patients in neurotherapeutics provide a framework for
analysis of ethical conflicts and the loss of public confidence in medical research. Parkinson advocates’ views on clinical
trial participation, perceived risks and benefits, placebo controls, and sham surgery are presented. These views reflect the
sense of urgency and the unique perspective that comes from living with this progressive, debilitating condition full time.
A patient-centered paradigm that includes authentic voices of patients as collaborators at every stage of development will
help to resolve conflicts, build trust, recruit trial participants, and accelerate new therapies. Key elements are adaptive
clinical trial methods and the development of information technology for the assessment of outcomes and surveillance of safety
over the life cycle of a medical product. Supported by the Parkinson’s Disease Foundation, the Parkinson Pipeline Project
is a grassroots group of Parkinson’s patients whose goal is to represent an authentic voice for patients in the treatment
development process. This group promotes education and communication between members of the Parkinson’s community and active
stakeholders in medical research, industry, and regulatory agencies. Its members are an example of a new breed of knowledgeable
consumers, armed with first-hand access to research findings and reinforced by on-line connections to like-minded peers throughout
the world. 相似文献
18.
The effectiveness of organizational interventions in reducing the adverse consequences of work–family conflict has produced mixed findings. This paper examines the relationship between the use of organizational ‘family friendly’ resources (such as crèche facilities, flexible working hours, and job sharing), with levels of work–family conflict, and job and family satisfaction over time. Using structural equation modelling, these associations were tested in 398 employed men and women who each completed a self‐report questionnaire administered on two occasions. The use of organizational interventions directly predicted increased levels of concurrent (Time 1) work–family interference and increased levels of subsequent (Time 2) job satisfaction. Both organizational interventions and family interventions (i.e. support) positively predicted subsequent family satisfaction. The research demonstrates that the provision of organizational ‘family‐friendly’ practices will produce improved psychological outcomes for employees. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
19.
Joseph Cofrancesco Nina Shah Khalil G Ghanem Adrian S Dobs Robert S Klein Kenneth Mayer Paula Schuman David Vlahov Anne M Rompalo 《Gynecological endocrinology》2006,22(5):244-251
Drug use and HIV infection may affect sex hormone levels in women. One hundred and ninety-six women with and without a history of illicit drug use (50 HIV-negative and 148 HIV-infected), with regular menses, who never used antiretrovirals, were evaluated. Luteinizing hormone levels were significantly higher in women with a CD4 cell count <200/microl (p < 0.002). Current methadone use was associated with lower levels of total testosterone (p = 0.03) and higher levels of prolactin (p = 0.002); mean estradiol levels were 43% lower in women who used intravenous drugs (p < 0.001). Alcohol and crack cocaine use was not associated with sex hormone levels. Age, race, body mass index and degree of HIV immunosuppression were also associated with differences in sex hormone levels. 相似文献
20.