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Novel Population (novel + population)
Selected AbstractsGlutamate Receptor Subunit ,2 Is Highly Expressed in a Novel Population of Glial-Like Cells in Rat Pineal Glands in CultureJOURNAL OF NEUROCHEMISTRY, Issue 3 2000Shouki Yatsushiro Abstract: The mammalian pineal gland uses L-glutamate as an intercellular chemical transmitter to regulate negatively melatonin synthesis. To receive glutamate signals, pinealocytes express at least three kinds of glutamate receptors: metabotropic receptor types 3 and 5 and an ionotropic receptor, GluR1. In this study, we examined whether or not the fourth class of ionotropic receptor, ,, which is known for its nondefinitive molecular function and its unique expression pattern in brain, is expressed in pineal gland. RT-PCR analyses with specific probes indicated the expression of mRNA of ,2 but not that of ,1 in pineal gland and cultured pineal cells. Western blotting analysis with polyclonal antibodies specific to the carboxyl-terminal region of the ,2 receptor recognized a single 110-kDa polypeptide of cerebellar membranes and specifically immunostained Purkinje cells. The ,2 antibodies recognized a 110-kDa polypeptide of pineal membranes and specifically immunostained huge glial-like cells with the occasional presence of several long, branching processes in a pineal cell culture. ,2 is not uniformly distributed throughout the cells and is relatively abundant at the periphery of the cell bodies and long processes, where the terminals of synaptophysin-positive processes of pinealocytes, a site for glutamate secretion, are frequently present. The ,2-positive cells constitute a very minor population among total pineal cells (,0.03%). Double immunolabeling with ,2 antibodies and antibodies against marker proteins for pineal interstitial cells clearly distinguishes ,2-positive pineal cells and other known interstitial cells, including glial fibrillary acidic protein- or vimentin-positive glial-like cells. These results indicated that the ,2 glutamate receptor is expressed in a novel subpopulation of pineal glial-like cells in culture and suggest the presence of a glutamate-mediated intercellular signal transduction mechanism between pinealocytes and ,2-expressing cells. The pineal cells may provide a good experimental system for studies on the function of glutamate receptor ,2. [source] Doublecortin expression in the normal and epileptic adult human brainEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2008Y. W. J. Liu Abstract Mesial temporal lobe epilepsy (MTLE) is a neurological disorder associated with spontaneous recurrent complex partial seizures and hippocampal sclerosis. Although increased hippocampal neurogenesis has been reported in animal models of MTLE, increased neurogenesis has not been reported in the hippocampus of adult human MTLE cases. Here we showed that cells expressing doublecortin (Dcx), a microtubule-associated protein expressed in migrating neuroblasts, were present in the hippocampus and temporal cortex of the normal and MTLE adult human brain. In particular, increased numbers of Dcx-positive cells were observed in the epileptic compared with the normal temporal cortex. Importantly, 56% of Dcx-expressing cells in the epileptic temporal cortex coexpressed both the proliferative cell marker, proliferating cell nuclear antigen and early neuronal marker, TuJ1, suggesting that they may be newly generated neurons. A subpopulation of Dcx-positive cells in the epileptic temporal cortex also coexpressed the mature neuronal marker, NeuN, suggesting that epilepsy may promote the generation of new neurons in the temporal cortex. This study has identified, for the first time, a novel population of Dcx-positive cells in the adult human temporal cortex that can be upregulated by epilepsy and thus, raises the possibility that these cells may have functional significance in the pathophysiology of epilepsy. [source] Granulocyte transfusion therapy in abdominal organ transplant recipientsJOURNAL OF CLINICAL APHERESIS, Issue 5 2009Nikhil R. Oak Abstract Background: Patients with neutropenia are at increased risk for infections. Granulocyte transfusions (GT) have had mixed success in treatment of neutropenic infections in adult patients with hematologic malignancy. This study examined the outcomes of GT therapy in neutropenic solid organ transplant recipients, a novel population for this therapy. Methods: We performed a retrospective examination of the transfusion and medical records of all 14 solid organ-transplant recipients without hematologic malignancy who experienced neutropenia and received GT therapy from 2004 to 2006. Results: Twelve patients received GT therapy for an active infection and two patients for infection prophylaxis. The mean absolute neutrophil count (ANC) one day increment per GT in these patients was 526/,l (median 215/,l). The mean ANC one day increment per dose of 1010 granulocytes was 246/,l (median 86/,l). Of the 12 infected patients, four patients (33%) showed a clinical response to GT with improvement or resolution of the infection, 7 (58%) patients had no clinical response and one additional patient had a clinical response to a course of GT but died during a second GT course. Neither patient receiving GT for prophylaxis developed an infection. Conclusions: We observed temporal increases in ANC to levels above 1,000/,l in 15/18 (83.3%) courses of GT. We observed a clinical response to infection in 5/12 (42%) patients, the remaining infected patients had no clinical response. Our results suggest that GT therapy in neutropenic solid organ transplant recipients can boost peripheral blood neutrophil counts. Additional studies areneeded to document an independent clinical benefit for GT in this patient population. J. Clin. Apheresis, 2009. © 2009 Wiley-Liss, Inc. [source] Specific central nervous system recruitment of HLA-G+ regulatory T cells in multiple sclerosis,ANNALS OF NEUROLOGY, Issue 2 2009Yu-Hwa Huang MSci Objective We have recently described a novel population of natural regulatory T cells (Treg) that are characterized by the expression of HLA-G and may be found at sites of tissue inflammation (HLA-Gpos Treg). Here we studied the role of these cells in multiple sclerosis (MS), a prototypic autoimmune inflammatory disorder of the central nervous system (CNS). Methods Sixty-four patients with different types of MS, 9 patients with other neurological diseases, and 20 healthy donors were included in this study. Inflamed brain lesions from 5 additional untreated MS patients were examined. HLA-Gpos Treg were analyzed in the cerebrospinal fluid (CSF) by flow cytometry and in inflammatory demyelinating lesions of MS brain specimens by immunohistochemistry. Functional capacity was accessed and transmigration was determined using an in vitro model of the human blood-brain barrier (BBB). Results HLA-Gpos Treg were found enriched in the inflamed CSF of MS patients and in inflammatory demyelinating lesions of MS brain specimens. HLA-Gpos Treg showed a strong propensity to transmigrate across BBB, which was vigorously driven by inflammatory chemokines, and associated with a gain of suppressive capacity upon transmigration. CSF-derived HLA-Gpos Treg of MS patients represented a population of activated central memory activated T cells with an upregulated expression of inflammatory chemokine receptors and exhibiting full suppressive capacity. Unlike natural FoxP3-expressing Treg, HLA-Gpos Treg derived from peripheral blood were functionally unimpaired in MS. Interpretation In MS, HLA-Gpos Treg may serve to control potentially destructive immune responses directly at the sites of CNS inflammation and to counterbalance inflammation once specifically recruited to the CNS. Ann Neurol 2009 [source] QUANTITATIVE ANALYSIS OF SHAPE VARIATION IN TYPE AND MODERN POPULATIONS OF MERIDION (BACILLARIOPHYCEAE)JOURNAL OF PHYCOLOGY, Issue 1 2001Kristina M. Rhode Subtle differences in valve morphology can indicate sexually isolated populations in diatoms (Bacillariophyceae). Shape descriptors, like Legendre coefficients, have been used to quantify differences in valve outline so that morphologically distinct groups can be recognized. Legendre coefficients were used as shape descriptors to quantify differences in valve outline among five populations in the genus Meridion Ag. Two novel populations of Meridion from North America, a North American population of M. constrictum Ralfs, type material for M. circulare (Greve.) Ag., and type material of M. constrictum were included in this analysis. Results of a principle components analysis and discriminate analyses on the shape descriptors of all five populations support the hypotheses that the two novel North American populations are undescribed taxa within Meridion and that the North American M. constrictum can be considered Meridion constrictum sensu stricto. A new taxon, Meridion hohii Rhode, is described. There appears to be greater diversity within the genus Meridion than is currently recognized. [source] | |||||||||||||