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1.
Febrile-range hyperthermia (FRH) improves survival in experimental infections by accelerating pathogen clearance, but may also increase collateral tissue injury. We hypothesized that FRH would worsen the outcome of inflammation stimulated by a non-replicating agonist and tested this hypothesis in a murine model of pulmonary oxygen toxicity. Using a conscious, temperature-controlled mouse model, we showed that maintaining a core temperature at FRH (39 degrees C to 40 degrees C) rather than at euthermic levels (36.5 degrees C to 37 degrees C) during hyperoxia exposure accelerated lethal pulmonary vascular endothelial injury, reduced the inspired oxygen threshold for lethality, induced expression of granulocyte-colony stimulating factor, and expanded the circulating neutrophil pool. In these same mice, FRH augmented pulmonary expression of the ELR(+) CXC chemokines, KC and LPS-induced CXC chemokine, enhanced recruitment of neutrophils, and changed the histological pattern of lung injury to a neutrophilic interstitial pneumonitis. Immunoblockade of CXC receptor-2 abrogated neutrophil recruitment, reduced pulmonary vascular injury, and delayed death. These combined data demonstrate that FRH may enlist distinct mediators and effector cells to profoundly shift the host response to a defined injurious stimulus, in part by augmenting delivery of neutrophils to sites of inflammation, such as may occur in infections. In certain conditions, such as in the hyperoxic lung, this process may be deleterious.  相似文献   
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A locus for recessive neurosensory nonsyndromic hearing impairmentmaps to chromosome 9q13–q21 in two regionally separateconsanguineous families from India. Each family demonstratesa LOD score greater than 4.5 to this region. D9S15, tightlylinked to the Friedreich's ataxia locus, a region that has beendefined with over 1 Mb of YAC contig information and severalexpressed sequences, is one of the flanking markers. In mice,the deafness (dn) locus maps to mouse chromosome 19 and flankingloci are syntenic to human chromosome 9q11–q21. The dnmouse is a potential model for the hearing impairment foundin both these families.  相似文献   
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Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for specific diagnosis of GM2 gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders.  相似文献   
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Background: Ageing is associated with an accumulation of free radical damage, which leads to physiological and clinical modifications. The study aims to find out the status of lipid profile, antioxidant enzymes, malondialdehyde in geriatric population. Patients/methods: The study was conducted on 150 subjects (75 healthy control between the ages of 20–30 years and 75 elderly subjects between ages of 50–70 years as cases). The following parameters were analyzed using the standard reference methods: lipid profile, reduced glutathione, glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase and malondialdehyde. Results: The present study was conducted to estimate the oxidative stress parameters in geriatric population. Highly significant increase in total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C), VLDL-cholesterol (VLDL-C), malondialdehyde, catalase and decrease in high density lipoprotein cholesterol (HDL-C), reduced glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase was observed in geriatrics when compared with their younger counterparts. Conclusion: This study concluded that there is enhanced oxidative stress and decreased antioxidant defence in geriatrics as compared to younger subjects which could play an important role in ageing. Dyslipidemia has become one of the important risk factors for the increasing prevalence of cardiovascular diseases. There is lack of awareness on the relationship between blood lipids and the risk of cardiovascular diseases in geriatric population. The strategy of early prevention should be adopted against dyslipidemia.  相似文献   
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Automated blood counts revealing lymphocytosis necessitate smear reviews. Even expert morphological evaluation may however, fail to differentiate a benign-versus-malignant etiology without further testing. Automated analyser-derived quantitative data on leukocyte cell populations remain undertested for distinguishing such etiologies. Instrument manufacturers claim that if successful, they may be used to generate software flags that help under-resourced laboratories better triage hemogram specimens requiring further testing. We tested the diagnostic accuracy of volume-conductivity-scatter (VCS) indices together with complete blood count (CBC) parameters in such scenarios. We compared LH780-derived (Beckman Coulter, FL, USA) CBC + VCS parameters from patients with clonal lymphoproliferations (n = 42, including 30 chronic lymphocytic leukemia cases) versus 83 controls with absolute or relative lymphocytosis (derivation cohort). Diagnostic performances of 11 logistic regression equations derived were subsequently evaluated on two specific validation cohorts (n = 130 and n = 1465). Clonal lymphocytoses showed significantly lower hemoglobin and higher leukocyte counts but similar lymphocyte percentages (LY %) vis-à-vis controls. The most significant, albeit overlapping predictor of clonality was the absolute lymphocyte count, LY# (47.8 ± 48.4 × 109/L vs. 2.9 ± 1.4 × 109/L in clonal vs. benign cases). In eleven logistic regression equations constructed using four combinatorial approaches, only the models with LY# (highest sensitivity/specificity of 99.3%/100%) and the lymphocytic VCS parameters alone (highest sensitivity/specificity of 76.2%/90.2%) performed consistently in both validation cohorts. Lymphocytic VCS parameters were moderately successful in distinguishing benign-versus-malignant lymphocytes. Other approaches of CBC-plus-VCS parameters did not sustain their initial excellent performances in the validation cohorts, highlighting a need for careful appraisal and better standardization of automated cellular analysis technologies.  相似文献   
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In addition to vision, light information is used to regulate a range of animal physiology. Such nonimage‐forming functions of light are mediated by nonvisual photoreceptors expressed in distinct neurons in the retina and the brain in most vertebrates. A nonvisual photoreceptor vertebrate ancient long opsin (VAL‐opsin) possesses two functional isoforms in the zebrafish, encoded by valopa and valopb, which has received little attention. To delineate the neurochemical identities of valop cells and to test for colocalization of the valop isoforms, we used in situ hybridization to characterize the expression of the valop genes along with that of neurotransmitters and a neuropeptide known to be present at the sites of valop expression. Double labeling showed that the thalamic valop population coexpresses valopa and valopb. All the thalamic valop cells overlapped with a GABAergic cell mass that continues from the anterior nucleus to the intercalated thalamic nucleus. A novel valopa cell population found in the superior raphe was serotonergic in nature. A valopb cell population in the Edinger‐Westphal nucleus was identified as containing thyrotropin‐releasing hormone. Valopb cells localized in the hindbrain intermediate reticular formation were noncholinergic in nature (nonmotorneurons). Thus, the presence of valop cell populations in different brain regions with coexpression of neurotransmitters and neuropeptides and the colocalization of valop isoforms in the thalamic cell population indicate regulatory and functional complexity of VAL‐opsin in the brain of the zebrafish. J. Comp. Neurol. 522:3847–3860, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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Purpose  

The tumor suppressor gene PTEN negatively regulates Akt, a downstream mediator phosphoinositol 3-kinase. Several studies have reported the role of PTEN gene in Akt downregulation and apoptosis induction in different cancers and cell lines. However, the role of loss of PTEN expression in Akt activation and spontaneous apoptosis in oral squamous cell carcinoma clinical specimens is not well established.  相似文献   
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