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971.
Melatoninergic neuroprotection of the murine periventricular white matter against neonatal excitotoxic challenge. 总被引:4,自引:0,他引:4
Isabelle Husson Bettina Mesplès Pierre Bac Joseph Vamecq Philippe Evrard Pierre Gressens 《Annals of neurology》2002,51(1):82-92
Periventricular leukomalacia is one of the main causes of cerebral palsy. Perinatal white matter lesions associated with cerebral palsy appears to involve glutamate excitotoxicity and excess free radical production. When injected intracerebrally into newborn mice, the glutamatergic analog ibotenate induces white matter cysts mimicking human periventricular leukomalacia. Melatonin acts on specific receptors. It also exhibits intrinsic free radical scavenging properties. The goal of the present study is to determine whether melatonin can protect against excitotoxic lesions induced by ibotenate in newborn mice. Mice that received intraperitoneal melatonin had an 82% reduction in size of ibotenate-induced white matter cysts when compared with controls. Although melatonin did not prevent the initial appearance of white matter lesions, it did promote secondary lesion repair. Axonal markers supported the hypothesis that melatonin induced axonal regrowth or sprouting. The protective effects of melatonin were suppressed by coadministration of luzindole, a melatonin receptor antagonist. Forskolin, an adenylate cyclase activator, prevented the protective effects of melatonin; inhibitors of protein kinase C and mitogen-associated protein kinase had no detectable effect. Melatonin and derivatives that block cAMP production through activation of melatonin receptors could represent new avenues for treating human periventricular leukomalacia. 相似文献
972.
T. Lombardi J. Samson F. Plantier C. Husson R. Küffer 《Journal of oral pathology & medicine》2004,33(2):115-120
BACKGROUND: Purposely, cosmetic injections in orofacial tissues of various resorbable, biodegradable, or permanent fillers may be followed by development of foreign-body granulomas. The aim of this article is to contribute to the histologic identification of the filler material. METHODS: Histologic and clinical features of 11 cases of granulomas on orofacial fillers are described. RESULTS: Only 3/11 patients knew the nature of the injected product. Four histologic patterns were found: (i) Artecoll, (ii) Dermalive, and (iii) New-Fill granuloma, all three of the classic giant cell granuloma type, differing in respect of foreign particles; and (iv) Liquid Silicone granuloma, which featured a cystic and macrophagic type. Information was often missing or misleading, patients or practitioners being reluctant to give the details. CONCLUSION: Increasing demand for orofacial tissue augmentation makes pathologists face new, and sometimes, puzzling granuloma types. Identification of the foreign product might be required for therapeutic or medico-legal reasons. 相似文献
973.
Influence of teicoplanin and vancomycin on degranulation by polymorphonuclear leucocytes stimulated by various agonists: an in-vitro study 总被引:1,自引:0,他引:1
The interaction between vancomycin and teicoplanin (50 and 100 mg/l) on human neutrophils was studied using fMLP- and A23187-induced degranulation of elastase, beta-glucuronidase and vitamin B12-binding-protein. Each of these proteins is a marker of a different population of granules. fMLP-induced degranulation of beta-glucuronidase was significantly impaired by pre-incubating the neutrophils with teicoplanin (without affecting cell viability) although the inhibition was at most 23% at 100 mg/l, a concentration not achieved in the serum of patients after normal doses. Calcium ionophore-induced degranulation of beta-glucuronidase and elastase were slightly impaired (Student two-tailed; P less than 0.1) by both glycopeptides (beta-glucuronidase) and teicoplanin only (elastase). Again, inhibition remained below 25%. Vancomycin and teicoplanin at high concentrations, seldom achieved in patients, can moderately impair neutrophil degranulation. 相似文献
974.
975.
The bio-inactivation of netilmicin and amikacin by binding with intact and disrupted human normal leucocytes was compared. Even after prolonged incubation of the aminoglycosides with intact cells, no binding could be demonstrated. On the other hand, partial binding of netilmicin and amikacin by disrupted leucocytes occurred: a linear relationship between the logarithm of the initial number of cells and the degree of binding of the drug was observed. The decrease in biological activity occurred rapidly in the presence of disrupted cells and remained unchanged during the next 18 h. 相似文献
976.
The purpose of this study was to examine the feasibility of a range of strategies to engage and to enhance secondary school nurse involvement in teenage smoking prevention and cessation. School nurses were willing to assist students to quit smoking, but they felt unprepared. Information provided by nurses involved in a three-stage review, pilot-testing, and trial design resulted in the development of a resource for nurses. This resource comprised individual student approaches (brief intervention based on motivational interviewing and written activities designed to help students examine their smoking behavior), approaches to assist parents (letter of support for parents of students who smoke), and school newsletter items. Each component of the resource was found by school nurses to be appropriate, useful, and complementary to their other school- wide approaches to assist adolescents to quit smoking. Nurses also reported an interest to expand or to enhance their smoking cessation role in the school. 相似文献
977.
Meghan Prin Takondwa Itaye Sarah Clark Rohesh J. Fernando Felix Namboya Gregor Pollach Nyengo Mkandawire Julia Sobol 《World journal of surgery》2016,40(11):2635-2642
Background
The provision of critical care services is essential to healthcare systems and increasingly a global health focus, but many hospitals in sub-Saharan Africa are unable to meet this need. Intensive care unit (ICU) mortality in this region is high, but studies describing the provision of critical care services are scarce.Methods
This was a retrospective cohort study of all patients admitted to the ICU at Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi, between September 1, 2013, and October 17, 2014. We summarized demographics, clinical characteristics, and outcomes, and analyzed factors associated with mortality.Results
Of 390 patients admitted to ICU during the study, 44.9 % of patients were male, and the median age was 22 years (IQR 6–35) years. Although most patients (73.1 %) were admitted with surgical diagnoses, the highest mortality was among patients admitted with sepsis (59.3 %), or obstetric (44.7 %) or medical (40.0 %) diagnoses. Overall ICU mortality was high (23.6 %).Conclusions
There is a shortage of data describing critical care in low-resource settings, particularly in sub-Saharan Africa. Surgical disease comprises the majority of ICU utilization in this study site, but medical and obstetric illness carried higher ICU mortality. These data may guide strategies for improving critical care in the region.978.
Hdac3 Deficiency Increases Marrow Adiposity and Induces Lipid Storage and Glucocorticoid Metabolism in Osteochondroprogenitor Cells
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979.
Nadeeka K. Wawegama Philip F. Markham Anna Kanci Meghan Schibrowski Sally Oswin Tamsin S. Barnes Simon M. Firestone Timothy J. Mahony Glenn F. Browning 《Journal of clinical microbiology》2016,54(5):1269-1275
Mycoplasma bovis is a pathogen of emerging significance in cattle throughout the world that is causing a range of diseases, including mastitis, arthritis, and pneumonia. The limited availability and efficacy of current diagnostic and prophylactic tools for its control and its increasing antimicrobial resistance are contributing to its increasing importance in beef and dairy cattle. We have developed an indirect IgG enzyme-linked immunosorbent assay (ELISA) based on a recombinant fragment of the MilA protein and have shown its potential as an effective diagnostic tool. To more comprehensively estimate the diagnostic sensitivity and specificity of this IgG ELISA for detection of infection with M. bovis in cattle and to define a suitable cutoff for use in the field, we further assessed its performance in experimentally infected calves in a closed beef herd and by applying Bayesian latent class modeling to laboratory testing results from 7,448 cattle entering Australian feedlots. The most effective cutoff points were estimated to be 68.6 antibody units (AU) for experimentally infected calves and to be 58.7 AU for a closed adult herd. Under field conditions, in feedlot cattle the globally optimal cutoff was estimated to be 105 AU. At this cutoff, the diagnostic sensitivity was 94.3% (95% probability interval [PI], 89.9% to 99.6%) with a diagnostic specificity of 94.4% (95% PI, 90.3% to 99.6%). Applying this 105 AU cutoff, 13.1% of cattle were seropositive for infection with M. bovis on entry into feedlots, and 73.5% were seropositive when followed up approximately 6 weeks later suggesting a high risk of infection shortly after entry into feedlots. 相似文献
980.
Mixed‐methods study identifies key strategies for improving infant and young child feeding practices in a highly stunted rural indigenous population in Guatemala
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Kelley Brown Nicole Henretty Anita Chary Meghan Farley Webb Heather Wehr Jillian Moore Caitlin Baird Anne Kraemer Díaz Peter Rohloff 《Maternal & child nutrition》2016,12(2):262-277
Guatemala's rural indigenous population suffers from one of the highest rates of chronic child malnutrition (stunting) in the world. Successfully addressing stunting requires defining the barriers to and opportunities for new behaviour‐change initiatives. We undertook a mixed‐methods assessment of feeding practices and food purchasing behaviours around infants and young children aged 6–36 months in two rural indigenous Guatemalan communities. We found that most caregivers were aware only of acute forms of child malnutrition and that they greatly underestimated the local prevalence of malnutrition. Despite moderate adherence to exclusive breastfeeding and timing of complementary food introduction, diets had poor diversity and inadequate meal frequency. Furthermore, perceptions of food insecurity were high even in the presence of land ownership and agricultural production. Although fortified foods were highly valued, they were considered expensive. At the same time, proportionally equivalent amounts of money were spent on junk foods or other processed foods by most participants. Biological mothers often lacked autonomy for food purchasing and nutritional decisions because of the power exerted by husbands and paternal grandmothers. Our findings suggest several creative and community‐based programming initiatives including education about the acute vs. chronic malnutrition distinction, engaging landowners in discussions about domestic food consumption, engaging with caregivers to redirect funds towards fortified foods rather than junk food purchases and directing behaviour‐change initiatives towards all household stakeholders. 相似文献