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201.
202.
We describe the case of a 29 weeks pregnant woman admitted after suffering her first generalised tonic-clonic seizure. Eclampsia was first ruled out by means of clinical history and analytical findings. The neurology department, after an exhaustive study, diagnosed the patient with cerebral neurocysticercosis. She received aetiological treatment which enabled her to have a normal pregnancy and delivery, thus avoiding a pre-term delivery, which is associated with high foetal morbidity and mortality. We also show the need to rule out non-endemic parasitic infection in our immigrant population.  相似文献   
203.
Molecular Basis for the Dominant White Phenotype in the Domestic Pig   总被引:11,自引:0,他引:11       下载免费PDF全文
The change of phenotypic traits in domestic animals and crops as a response to selective breeding mimics the much slower evolutionary change in natural populations. Here, we describe that the dominant white phenotype in domestic pigs is caused by two mutations in the KIT gene encoding the mast/stem cell growth factor receptor (MGF), one gene duplication associated with a partially dominant phenotype and a splice mutation in one of the copies leading to the fully dominant allele. The splice mutation is a G to A substitution in the first nucleotide of intron 17 and leads to skipping of exon 17. The duplication is most likely a regulatory mutation affecting KIT expression, whereas the splice mutation is expected to cause a receptor with impaired or absent tyrosine kinase activity. Immunocytochemistry showed that this variant form is expressed in 17- to 19-day-old pig embryos. Hundreds of millions of white pigs around the world are assumed to be heterozygous or homozygous for the two mutations.  相似文献   
204.
Cryopreservation introduces extreme temperature and osmolality changes that impart lethal and sublethal effects on spermatozoa. Additionally, there is evidence that the osmotic stress induced by cryopreservation causes oxidative stress to spermatozoa. The main sources of reactive oxygen species in mammalian sperm are the mitochondria. In view of this, the aim of our study was to test whether or not osmotic stress was able to induce mitochondrial damage and to explore the osmotic tolerance of the mitochondria of stallion spermatozoa. Ejaculates from 7 stallions were subjected to osmolalities ranging from 75 to 1500 mOsm/kg, and the effect on sperm membrane integrity and mitochondrial membrane potential was studied. Additionally, the effects of changes in osmolality from hyposmotic to isosmotic and from hyperosmotic to isosmotic solutions were studied (osmotic excursions). The cellular volume of stallion spermatozoa under isosmotic conditions was 20.4 ± 0.33 μm(3). When exposed to low osmolality, the stallion spermatozoa behaved like a linear osmometer, whereas exposure to high osmolalities up to 900 mOsm/kg resulted in decreased sperm volume. Although sperm membranes were relatively resistant to changes in osmolality, mitochondrial membrane potential decreased when osmolalities were low or very high (10.7 ± 1.74 and 16.5 ± 1.70 at 75 and 150 mOsm/kg, respectively, and 13.1 ± 1.83 at 1500 mOsm/kg), whereas in isosmolar controls the percentage of stallion sperm mitochondria with a high membrane potential was 41.1 ± 1.69 (P < .01). Osmotic excursions induced greater damage than exposure of spermatozoa to a given nonphysiologic osmolality, and again the mitochondria were more prone to damage induced by osmotic excursions than was the sperm plasma membrane. In search of intracellular components that could mediate these changes, we have detected for the first time the c-Jun N-terminal kinase 1/2 in stallion spermatozoa, which are apparently involved in the regulation of the viability of these cells.  相似文献   
205.
This paper focuses on the issue of longer appointment lead-time in the obstetrics outpatient department of a maternal-child hospital in Colombia. Because of extended appointment lead-time, women with high-risk pregnancy could develop severe complications in their health status and put their babies at risk. This problem was detected through a project selection process explained in this article and to solve it, Six Sigma methodology has been used. First, the process was defined through a SIPOC diagram to identify its input and output variables. Second, six sigma performance indicators were calculated to establish the process baseline. Then, a fishbone diagram was used to determine the possible causes of the problem. These causes were validated with the aid of correlation analysis and other statistical tools. Later, improvement strategies were designed to reduce appointment lead-time in this department. Project results evidenced that average appointment lead-time reduced from 6,89 days to 4,08 days and the deviation standard dropped from 1,57 days to 1,24 days. In this way, the hospital will serve pregnant women faster, which represents a risk reduction of perinatal and maternal mortality.  相似文献   
206.
Reduced Paneth cell alpha-defensins in ileal Crohn's disease   总被引:17,自引:0,他引:17       下载免费PDF全文
The pathogenesis of Crohn's disease (CD), an idiopathic inflammatory bowel disease, is attributed, in part, to intestinal bacteria that may initiate and perpetuate mucosal inflammation in genetically susceptible individuals. Paneth cells (PC) are the major source of antimicrobial peptides in the small intestine, including human alpha-defensins HD5 and HD6. We tested the hypothesis that reduced expression of PC alpha-defensins compromises mucosal host defenses and predisposes patients to CD of the ileum. We report that patients with CD of the ileum have reduced antibacterial activity in their intestinal mucosal extracts. These specimens also showed decreased expression of PC alpha-defensins, whereas the expression of eight other PC products either remained unchanged or increased when compared with controls. The specific decrease of alpha-defensins was independent of the degree of inflammation in the specimens and was not observed in either CD of the colon, ulcerative colitis, or pouchitis. The functional consequence of alpha-defensin expression levels was examined by using a transgenic mouse model, where we found changes in HD5 expression levels, comparable to those observed in CD, had a pronounced impact on the luminal microbiota. Thus, the specific deficiency of PC defensins that characterizes ileal CD may compromise innate immune defenses of the ileal mucosa and initiate and/or perpetuate this disease.  相似文献   
207.
CB(2) cannabinoid receptor-selective agonists are promising candidates for the treatment of pain. CB(2) receptor activation inhibits acute, inflammatory, and neuropathic pain responses but does not cause central nervous system (CNS) effects, consistent with the lack of CB(2) receptors in the normal CNS. To date, there has been virtually no information regarding the mechanism of CB(2) receptor-mediated inhibition of pain responses. Here, we test the hypothesis that CB(2) receptor activation stimulates release from keratinocytes of the endogenous opioid beta-endorphin, which then acts at opioid receptors on primary afferent neurons to inhibit nociception. The antinociceptive effects of the CB(2) receptor-selective agonist AM1241 were prevented in rats when naloxone or antiserum to beta-endorphin was injected in the hindpaw where the noxious thermal stimulus was applied, suggesting that beta-endorphin is necessary for CB(2) receptor-mediated antinociception. Further, AM1241 did not inhibit nociception in mu-opioid receptor-deficient mice. Hindpaw injection of beta-endorphin was sufficient to produce antinociception. AM1241 stimulated beta-endorphin release from rat skin tissue and from cultured human keratinocytes. This stimulation was prevented by AM630, a CB(2) cannabinoid receptor-selective antagonist and was not observed in skin from CB(2) cannabinoid receptor-deficient mice. These data suggest that CB(2) receptor activation stimulates release from keratinocytes of beta-endorphin, which acts at local neuronal mu-opioid receptors to inhibit nociception. Supporting this possibility, CB(2) immunolabeling was detected on beta-endorphin-containing keratinocytes in stratum granulosum throughout the epidermis of the hindpaw. This mechanism allows for the local release of beta-endorphin, where CB(2) receptors are present, leading to anatomical specificity of opioid effects.  相似文献   
208.
Tyrosine kinase inhibitors have revolutionized the treatment of chronic myeloid leukemia and are increasingly used for other indications. Fluid retention, however, including pleural effusions, are a significant side effect of imatinib, the first-line treatment for chronic myeloid leukemia. We investigated pleural and pulmonary complications in patients treated with dasatinib, a novel multitargeted tyrosine kinase inhibitor, as part of clinical trial protocols. Of 40 patients who received dasatinib (70 mg twice daily) for imatinib resistance or intolerance, 9 (22.5%) developed dyspnea, cough, and chest pain. Of these nine patients, six had pleural effusions (all were exudates) and seven had lung parenchyma changes with either ground-glass or alveolar opacities and septal thickening (four patients had both pleural effusions and lung parenchyma changes). Lymphocytic accumulations were detected in pleural and bronchoalveolar lavage fluids in all patients except for one who presented with neutrophilic alveolitis. Pleural biopsies revealed lymphocytic infiltration in one patient and myeloid infiltration in another. After dasatinib interruption, lung manifestations resolved in all cases and did not recur in three of four patients when dasatinib was reintroduced at a lower dose (40 mg twice daily). Thus, lung physicians should be aware that lung manifestations, presumably related to an immune-mediated mechanism rather than fluid retention, may occur with dasatinib treatment.  相似文献   
209.
OBJECTIVE: The objective of this study is to determine the association between risk factors and nonalcoholic fatty liver disease (NAFLD), and to establish the relationship between risk factors and hepatic histological changes in obese women. METHODS: A case-control design study. Women with NAFLD (cases) were compared with a control group of obese women without NAFLD matched by age, body mass index, waist circumference, and body fat. Irrespective of serum aminotransferases levels, diagnosis of NAFLD was established by the presence of type II diabetes, hypertriglyceridemia, and ultrasonographic changes of hepatic steatosis. Diagnosis of nonalcoholic steatohepatitis was performed by a liver biopsy. Women with an aspartate aminotransferase/alanine aminotransferase (ALT) ratio of at least 1 underwent liver biopsy. Alcohol consumption, hepatitis, and drugs that promote cholestasis or liver injury were the exclusion criteria. Multiple regression analysis was used to compute the association between the risk factors and NAFLD, and Spearman's analysis was used to examine its relationship with histological hepatic changes. RESULTS: A total of 108 obese women were enrolled. The frequency of high blood pressure, hypertriglyceridemia, and diabetes was similar between the groups. ALT (54.4+/-33.3 and 39.8+/-29.8, P=0.03) but not aspartate aminotransferase (45.4+/-23.1 and 36.7+/-21.2, P=0.06) was significantly higher in the women with NAFLD. The multivariate regression analysis showed a significant association of ALT (odds ratio 2.7; 95% confidence interval, 1.3-10.4), but not other variables with NAFLD. Type II diabetes was strongly correlated with ballooning and inflammation, and ALT with inflammation and fibrosis. CONCLUSION: Obese women with similar metabolic alterations exhibit different hepatic outcomes. Elevation of ALT, but not other risk factors, was associated with NAFLD. Diabetes and ALT correlate with histological hepatic changes.  相似文献   
210.
Management of acute pain remains a significant clinical problem. In preclinical studies, CB2 cannabinoid receptor-selective agonists inhibit nociception without producing central nervous system side effects. The CB2 receptor-selective agonist AM1241 produces antinociceptive effects that are antagonized by CB2, but not CB1, receptor-selective antagonists, suggesting that activation of CB2 receptors results in antinociception. However, it has not been possible to definitively demonstrate that these effects are mediated by CB2 receptors, because we have lacked the pharmacological tools to confirm the in vivo receptor selectivity of the antagonists used. Further, recent evidence for cannabinoid-like receptors beyond CB1 and CB2 raises the possibility that AM1241 exerts its antinociceptive effects at uncharacterized CB2-like receptors that are also inhibited by AM630. The experiments reported here further test the hypothesis that CB2 receptor activation inhibits nociception. They evaluated the antinociceptive actions of AM1241 and the less-selective CB2 receptor agonist WIN55,212-2 in wild-type (CB2+/+) mice and in mice with genetic disruption of the CB2 receptor (CB2-/- mice). AM1241 inhibited thermal nociception in CB2+/+ mice, but had no effect in CB2-/- littermates. WIN55,212-2 produced equivalent antinociception in CB1+/+ and CB1-/- mice, while its antinociceptive effects were reduced in CB2-/- compared to CB2+/+ mice. The effects of morphine were not altered in CB2-/- compared to CB2+/+ mice. These data strongly suggest that AM1241 produces antinociception in vivo by activating CB2 cannabinoid receptors. Further, they confirm the potential therapeutic relevance of CB2 cannabinoid receptors for the treatment of acute pain.  相似文献   
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