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The effect of agitation on granulocyte storage was examined. Granulocyte concentrates were obtained as buffy coats from fresh blood by centrifugation and stored for up to 48 hours at 22 degrees C with or without horizontal agitation (80 rpm). The cell counts, mean cell volumes, morphologic changes, phagocytosis, and bactericidal activity of the stored granulocytes did not differ significantly. However, chemotaxis was maintained better in granulocytes that were agitated. At 48 hours, the ability of unagitated cells to adhere to both immunoglobulin-coated and uncoated glass surfaces increased, and clumps were observed on the surfaces. These results seem to be related to the decrease in chemotaxis. The pH of unagitated sedimented cells was more acid. To avoid the decrease of this local pH, stored granulocytes need gentle agitation. 相似文献
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Naho Fujiwara Katsumi Miyahara Nana Nakazawa-Tanaka Chihiro Akazawa Atsuyuki Yamataka 《Journal of pediatric surgery》2018,53(2):326-329
Purpose
Semaphorins are guidance cues for developing neurons, implicated in the determination of the migratory pathway of neural crest-derived neural precursors during enteric nervous system development. Recently, it has been reported that Semaphorin 3A (SEMA3A) expression is up-regulated in the aganglionic colon in Hirschsprung disease (HD) patients, suggesting that increased SEMA3A expression may be a risk factor for HD. Thus, the aim of our study was to determine the expression of SEMA3A using Sox10-Venus mice gut.Methods
We harvested the gut on postnatal day 2 (P2). SOX10-Venus +/EDNRB?/? mice were compared with SOX10-Venus +/EDNRB+/+ mice as controls. QRT-PCR was performed to determine gene expression of SEMA3A (n = 8). Fluorescent immunohistochemistry was performed to assess protein distribution.Results
On P2, gene expression levels of SEMA3A were significantly increased in the HD group compared to controls in the proximal and distal colon (p < 0.05). Laser scanning microscopy revealed SEMA3A expression was localized within the submucosa and muscle layer of the gut in both HD and controls. In HD, SEMA3A was highly expressed in the proximal and distal colon.Conclusions
In the present study, we demonstrated that SEMA3A expression is increased in the EDNRB ?/? HD model on P2, suggesting that SEMA3A may interfere with ENCC migration, resulting in an absence of enteric neurons. 相似文献114.
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Neurotrophic factor receptors in epiretinal membranes after human diabetic retinopathy 总被引:7,自引:0,他引:7
Harada T Harada C Mitamura Y Akazawa C Ohtsuka K Ohno S Takeuchi S Wada K 《Diabetes care》2002,25(6):1060-1065
OBJECTIVE: Formation of epiretinal membranes (ERMs) in the posterior fundus results in progressive deterioration of vision. ERMs have been associated with numerous clinical conditions, including proliferative diabetic retinopathy (PDR), but its pathogenic mechanisms are still unknown. This study was conducted to determine whether neurotrophic factor receptors (tyrosine kinase receptors trkA, trkB, and trkC; low-affinity neurotrophin [NT] receptor p75 [p75(NTR)]; glial cell line-derived neurotrophic factor receptor-alpha1 [GFR alpha 1] and GFR alpha 2; and Ret) are involved in the formation of ERMs after PDR. RESEARCH DESIGN AND METHODS: ERM samples were obtained by vitrectomy from 19 subjects with PDR aged 57 +/- 8 years with 17 +/- 8 years of diabetes and 15 subjects with idiopathic ERM. They were processed for RT-PCR analysis. In addition, 11 ERM samples from PDR patients aged 47 +/- 18 years with 13 +/- 4 years of diabetes were processed for immunohistochemical analysis. RESULTS: Expressions of trkA, trkB, trkC, p75(NTR), and Ret mRNAs were similar in both groups. In contrast, GFR alpha 2 expression levels were significantly higher (17 of 19 vs. 2 of 15 subjects in idiopathic ERM, P < 0.0001) in PDR subjects. Accordingly, immunohistochemical analysis revealed expression of GFR alpha 2 protein in all of the 11 ERMs derived from PDR patients, and that region was double-labeled with glial cell-specific markers. On the other hand, GFR alpha 1 expression was lower (8 of 19 vs. 12 of 15 subjects with idiopathic ERM, P = 0.0258) in PDR subjects. CONCLUSIONS: These results suggest a possibility that glial cell line-derived neurotrophic factor receptor (GDNF) subtypes are differently involved in the formation of ERMs. 相似文献
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Extent of Laminin-5 Assembly and Secretion Effect Junctional Epidermolysis Bullosa Phenotype 总被引:1,自引:0,他引:1 下载免费PDF全文
Chihiro Matsui Phyllis Pereira C. Kathy Wang Charlotte F. Nelson Timothy Kutzkey Caroline Lanigan David Woodley Masaaki Morohashi Elizabeth A. Welsh Warren K. Hoeffler 《The Journal of experimental medicine》1998,187(8):1273-1283
Junctional epidermolysis bullosa (JEB) is an autosomal recessive skin blistering disease with both lethal and nonlethal forms, with most patients shown to have defects in laminin-5. We analyzed the location of mutations, gene expression levels, and protein chain assembly of the laminin-5 heterotrimer in six JEB patients to determine how the type of genetic lesion influences the pathophysiology of JEB. Mutations within laminin-5 genes were diversely located, with the most severe forms of JEB correlating best with premature termination codons, rather than mapping to any particular protein domain. In all six JEB patients, the laminin-5 assembly intermediates we observed were as predicted by our previous work indicating that the α3β3γ2 heterotrimer assembles intracellularly via a β3γ2 heterodimer intermediate. Since assembly precedes secretion, mutations that disrupt protein–protein interactions needed for assembly are predicted to limit the secretion of laminin-5, and likely to interfere with function. However, our data indicate that typically the most severe mutations diminish mRNA stability, and serve as functional null alleles that block chain assembly by resulting in either a deficiency (in the nonlethal mitis variety) or a complete absence (in lethal Herlitz-JEB) of one of the chains needed for laminin-5 heterotrimer assembly. 相似文献
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Chihiro Shingu Hironori Koga Satoshi Hagiwara Shigekiyo Matsumoto Koji Goto Isao Yokoi Takayuki Noguchi 《Journal of anesthesia》2010,24(4):569-574