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691.

Glioblastoma (GB) is the most common primary brain tumour in adults. The lack of molecular biomarker, non-specific symptoms and fast growth rate often result in a significant delay in diagnosis. Despite multimodal treatment, the prognosis remains poor. Here, we verified the hypothesis that amino acids (AA) regulating the critical metabolic pathways necessary for maintenance, growth, reproduction, and immunity of an organism, may constitute a favourable target in GB biomarker research. We measured the plasma amino acids levels in 18 GB patients and 15 controls and performed the quantitative and qualitative metabolomic analysis of free AA applying high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). We present both the raw data and the results of our statistical analysis. The majority of AA were lowered in the study group in comparison to the control group. Five of these (arginine, glutamic acid, glutamine, glycine, and histidine) differed significantly (all p < 10–5 and AUC > 0.9). Plasma levels of leucine and phenylalanine decreased in the case of GB with lost alpha-thalassemia/mental retardation X-linked (ATRX) expression on immunohistochemistry (p = 0.003 and 0.045, respectively). We demonstrated for the first time that certain plasma-free AA levels of GB patients were significantly different from those in healthy volunteers. Target profiling of plasma-free AA, identified utilizing LC-QTOF-MS, may present prognostic value by indicating GB patients with lost ATRX expression. The on-going quest for glioma biomarkers still aims to determine the detailed metabolic profile and evaluate its impact on therapy and prognosis.

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692.
Analyses of the breadth and specificity of virus-specific CD8(+) T cell responses associated with control of HIV have largely relied on measurement of cytokine secretion by effector T cells. These have resulted in the identification of HIV elite controllers with low or absent responses in which non-T-cell mechanisms of control have been suggested. However, successful control of HIV infection may be associated with central memory T cells, which have not been consistently examined in these individuals. Gag-specific T cells were characterized using a peptide-based cultured enzyme-linked immunosorbent spot assay (ELISpot). Peripheral blood mononuclear cells from HIV elite controllers (n = 10), progressors (n = 12), and antiretroviral-treated individuals (n = 9) were cultured with overlapping peptides for 12 days. Specificity was assessed by tetramer staining, functional features of expanded cells were assessed by cytokine secretion, and virus inhibition and phenotypic characteristics were assessed by cell sorting and coculture assays. After peptide stimulation, elite controllers showed a greater number of previously undetectable (new) responses compared to progressors (P = 0.0008). These responses were highly polyfunctional, with 64.5% of responses having 3 to 5 functions. Expandable epitope-specific CD8(+) T cells from elite controllers had strong virus inhibitory capacity and predominantly displayed a central memory phenotype. These data indicate that elite controllers with minimal T cell responses harbor a highly functional, broadly directed central memory T cell population that is capable of suppressing HIV in vitro. Comprehensive examination of this cell population could provide insight into the immune responses associated with successful containment of viremia.  相似文献   
693.
? Premise of the study: Arabidopsis halleri is a model species to study the adaptation of plants to soils contaminated by zinc, cadmium, and lead. To provide a neutral genetic background with which adaptive genetic markers could be compared, we developed highly polymorphic neutral microsatellite markers. ? Methods and Results: Using a microsatellite-enriched library method, we identified 120 microsatellite loci for quantitative trait locus (QTL) mapping analysis, of which eight primer pairs were developed in a single multiplex for population genetic studies. Analyses were performed on 508 individuals from 26 populations. All loci were polymorphic with six to 23 alleles per locus. Genetic diversity varied between 0.56 and 0.76. ? Conclusions: Our results demonstrated the value of these eight microsatellite markers to investigate neutral population genetic structure in A. halleri. To increase the resolution of population genetic analyses, we suggest adding them to the 11 markers previously developed independently.  相似文献   
694.
Usher syndrome is rare genetic disorder impairing two human senses, hearing and vision, with the characteristic late onset of vision loss. This syndrome is divided into three types. In all cases, the vision loss is postlingual, while loss of hearing is usually prelingual. The vestibular functions may also be disturbed in Usher type 1 and sometimes in type 3. Vestibular areflexia is helpful in making a proper diagnosis of the syndrome, but, often, the syndrome is misdiagnosed as a nonsyndromic hearing loss. Here, we present a Polish family with hearing loss, which was clinically classified as nonsyndromic. After excluding mutations in the DFNB1 locus, we implemented the next-generation sequencing method and revealed that hearing loss was syndromic and mutations in the USH2A gene indicate Usher syndrome. This research highlights the importance of molecular analysis in establishing a clinical diagnosis of congenital hearing loss.  相似文献   
695.
RAM11 is a mouse monoclonal anti-rabbit macrophage antibody recognizing connective tissue and vascular (atheromatous tissue) macrophages. This study demonstrates a cross-reaction of RAM11 with an unknown antigen in rabbit normal epithelial cells. Formalin-fixed, paraffin sections of the New Zealand White rabbit normal skin, oral mucosa, esophagus, small intestine and lung were immunostained with RAM11 antibody followed by goat anti-mouse Cy-3-conjugated antiglobulin. RAM11-positive immunofluorescence was observed in basal layer cells of stratified squamous epithelia (skin, oral mucosa, esophagus). No RAM11 immunostaining was found in any cells of simple (intestinal, bronchial) epithelia. These findings show that basal cells of stratified squamous keratinized and non-keratinized epithelia of the rabbit express an antigenic epitope which is common with that of macrophage antigen recognized by RAM11 monoclonal antibody.  相似文献   
696.
Cystic fibrosis (CF) is genetically determined illness, which is caused by the mutation in the CFTR gene. CFTR protein is also expressed in epithelial cells of parotid glands, therefore parotid glands are also affected in CF patients. Cathepsin D is one of the proteolitic cascade enzymes. Physiological wearing out result in occurrence of trace quantities of this enzyme in serum and body fluids, including saliva. Among different enzymes, saliva contains cathepsin D (CTSD, EC 3.4.23.5). The aim of this study was to determine cathepsin D activity in mixed saliva in cystic fibrosis patients and healthy controls. The study was performed in a group of 26 CF patients (10F, 16M). The results obtained in CF group was compared with the results of thirty healthy subjects (12F, 14M). From each subject 8 ml of mixed saliva was obtained: before and after the stimulation of saliva excretion using paraffin pledgets. Protein and glycoprotein content was assessed using Winzler's method. Protein concentration in controls and CF group before stimulation of excretion was 1.15+/-0.714 mg/mL and 1.54+/-0.925 mg/mL. After stimulation protein concentration in saliva has lowered to 0.88+/-0.77 mg/mL in CF group and 1.24+/-1.213 mg/mL in controls. Glycoprotein concentration in controls and in CF group was respectively: before stimulation 1.08+/-0.271 mg/mL and 1.05+/-0.344 mg/mL; after stimulation 0.92+/-0.292 mg/mL and 0.86+/-0.283 mg/mL. The activity of CTSD in controls was 45.9+/-24.98 Tyr nmol/mL/4h before stimulation and 109.3+/-56.94 Tyr nmol/mL/4h after stimulation of excretion. In CF group CTSD activity before stimulation was 134.5+/-81.80 Tyr nmol/mL/4h and after stimulation 134.4+/-62.18 Tyr nmol/mL/4h. Comparing the CTSD activity in both groups statistically significant difference has been revealed in samples collected before stimulation of excretion (p=0.013). The activity of cathepsin D in saliva of cystic fibrosis patient is significantly higher than in healthy controls before the stimulation of excretion with paraffin pledgets.  相似文献   
697.
Transforming growth factor-beta (TGF-beta) signaling plays a pivotal role in extracellular matrix deposition by stimulating collagen production and other extracellular matrix proteins and by inhibiting matrix degradation. The present study was undertaken to define the role of sphingosine kinase (SphK) in TGF-beta signaling. TGF-beta markedly up-regulated SphK1 mRNA and protein amounts and caused a prolonged increase in SphK activity in dermal fibroblasts. Concomitantly, TGF-beta reduced sphingosine-1-phosphate phosphatase activity. Consistent with the changes in enzyme activity, corresponding changes in sphingolipid levels were observed such that sphingosine 1-phosphate (S1P) was increased (approximately 2-fold), whereas sphingosine and ceramide were reduced after 24 h of TGF-beta treatment. Given the relatively early induction of SphK gene expression in response to TGF-beta, we examined whether SphK1 may be involved in the regulation of TGF-beta-inducible genes that exhibit compatible kinetics, e.g. tissue inhibitor of metalloproteinase-1 (TIMP-1). We demonstrate that decreasing SphK1 expression by small interfering RNA (siRNA) blocked TGF-beta-mediated up-regulation of TIMP-1 protein suggesting that up-regulation of SphK1 contributes to the induction of TIMP-1 in response to TGF-beta. The role of SphK1 as a positive regulator of TIMP-1 gene expression was further corroborated by using ectopically expressed SphK1 in the absence of TGF-beta. Adenovirally expressed SphK1 led to a 2-fold increase of endogenous S1P and to increased TIMP-1 mRNA and protein production. In addition, ectopic SphK1 and TGF-beta cooperated in TIMP-1 up-regulation. Mechanistically, experiments utilizing TIMP-1 promoter constructs demonstrated that the action of SphK1 on the TIMP-1 promoter is through the AP1-response element, consistent with the SphK1-mediated up-regulation of phospho-c-Jun levels, a key component of AP1. Together, these experiments demonstrate that SphK/S1P are important components of the TGF-beta signaling pathway involved in up-regulation of the TIMP-1 gene.  相似文献   
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Differences were shown in histological localization of psoralensof Angelica archangelica, Daucus carota, Sium suave and Psoraleabituminosa. All the fruits examined contained furanocoumarinson the surface. Fruit tissues contained very low (Sium), medium(Angelica) or high (Psoralea) concentrations of these compounds.Seed covers showed low autofluorescence in Angelica but highin Sium . Not all the glands in fruit or seed tissue exhibitedautofluorescence. Embryos always contained furanocoumarins ontheir surface and in their tissues in varying proportions. Autofluorescencecan be homogeneously distributed among all cells of the embryo(Sium) or can be concentrated in certain cells (Psoralea).Copyright1993, 1999 Academic Press Autofluorescence, furanocoumarins  相似文献   
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