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221.
目的:探讨非小细胞肺癌(non-smallcelllungcancer,NSCLC)组织Medl9蛋白表达与DNA倍体和s期比例(Sphasefraction,SPF)的关系。方法:收集山东省肿瘤医院2010—02—01—2011-07—31手术治疗、临床病理资料完整的56例NSCLC组织,应用免疫组化技术检测56例NSCLC组织中Medl9蛋白水平,应用流式细胞术检测癌组织DNA倍体和SPF。结果:56例NSCLC组织中Medl9阳性45例,阴性11例,二倍体14例,异倍体42例。14例二倍体肿瘤中Medl9蛋白表达阴性6例,阳性8例;42例异倍体肿瘤中Medl9蛋白表达阳性37例,阴性5例,异倍体肿瘤Medl9蛋白阳性表达显著高于二倍体肿瘤,X2=6.373,P=0.012。27例低SPF的患者中Medl9蛋白表达阴性9例,阳性18例;29例高SPF的患者中Medl9蛋白表达阴性2例,阳性27例,高SPF的患者肿瘤组织Medl9蛋白阳性表达显著高于低SPF患者,P=0.018。结论:Medl9作为潜在癌基因在NSCLC细胞增殖和多倍体形成中起一定作用,有望成为一个新的肿瘤治疗靶点。  相似文献   
222.
Airborne transmission of H5N1 highly pathogenic avian influenza (HPAI) viruses has occurred among poultry and from poultry to humans during home or live-poultry market slaughter of infected poultry, and such transmission has been experimentally reproduced. In this study, we investigated simple, practical changes in the processing of H5N1 virus-infected chickens to reduce infectious airborne particles and their transmission. Our findings suggest that containing the birds during the killing and bleeding first step by using a disposable plastic bag, a commonly available cooking pot widely used in Egypt (halla), or a bucket significantly reduces generation of infectious airborne particles and transmission to ferrets. Similarly, lack of infectious airborne particles was observed when processing vaccinated chickens that had been challenged with HPAI virus. Moreover, the use of a mechanical defeatherer significantly increased total number of particles in the air compared to manual defeathering. This study confirms that simple changes in poultry processing can efficiently mitigate generation of infectious airborne particles and their transmission to humans.  相似文献   
223.
The aim of our study was to analyse the possible protective effect of quercetin application during the jejunal ischemia-reperfusion injury (IRI) in rats. Quercetin was administered intraperitoneally 30 min before 1 h ischemia of superior mesenteric artery with following 24 h lasting reperfusion period. The male specific pathogen-free (SPF) Charles River Wistar rats were used. In the group with applied quercetin, the significantly increased (p < 0.001) levels of anti-inflammatory cytokine IL10 were observed both in the blood serum and jejunal tissue. The improvement of the mucosal tissue morphology and proliferating and DNA repairing cell number measured by PCNA activity were recorded by more than 30% higher in the quercetin group. Simultaneously, significant elongation of the intestinal glands (p < 0.001) and increase in the number of CD68-positive cells in the lamina propria mucosae (p < 0.001) in comparison with control group were found. Based on our results, the preventive application of quercetin before induction of jejunal IRI stimulates faster jejunal mucosa restoration and it seems to have immunomodulatory and anti-inflammatory effects as well. CD68-positive macrophages could have crucial role in this process since they work as both growth factor and cytokine producers.  相似文献   
224.
BACKGROUND & AIMS: To explore the hypothesis that selective immune responses to distinct components of the intestinal microflora induce intestinal inflammation, we characterized disease kinetics and bacterial antigen-specific T-cell responses in ex germ-free interleukin 10 -/- and wild-type control mice monoassociated with Enterococcus faecalis , Escherichia coli , or Pseudomonas fluorescens . METHODS: Colitis was measured by using blinded histological scores and spontaneous interleukin 12 secretion from colonic strip culture supernatants. Interferon gamma secretion was measured from mesenteric or caudal lymph node CD4 + T cells stimulated with bacterial lysate-pulsed antigen-presenting cells. Luminal bacterial concentrations were measured by culture and quantitative polymerase chain reaction. RESULTS: Escherichia coli induced mild cecal inflammation after 3 weeks of monoassociation in interleukin 10 -/- mice. In contrast, Enterococcus faecalis-monoassociated interleukin 10 -/- mice developed distal colitis at 10-12 weeks that was progressively more severe and associated with duodenal inflammation and obstruction by 30 weeks. Neither bacterial strain induced inflammation in wild-type mice, and germ-free and Pseudomonas fluorescens-monoassociated interleukin 10 -/- mice remained disease free. CD4 + T cells from Enterococcus faecalis- or Escherichia coli-monoassociated interleukin 10 -/- mice selectively produced higher levels of interferon gamma and interleukin 4 when stimulated with antigen-presenting cells pulsed with the bacterial species that induced disease; these immune responses preceded the onset of histological inflammation in Enterococcus faecalis -monoassociated mice. Luminal bacterial concentrations did not explain regional differences in inflammation. CONCLUSIONS: Different commensal bacterial species selectively initiate immune-mediated intestinal inflammation with distinctly different kinetics and anatomic distribution in the same host.  相似文献   
225.
Anaerobic Gram-negative bacteria dominate in periodontitis locations, while Gram-positive bacteria characterize healthy sites. A well-established Gram-positive flora might therefore inhibit the colonization of Gram-negative pathogens. The purpose of the present investigation was to examine whether endogenous S. sanguis could prevent, or reduce, periodontal bone loss in rats infected with a virulent P. gingivalis strain. Sixty specific pathogen-free Wistar rats were divided into 6 groups. Doxycycline was administered in the drinking water for 2 weeks to the groups A, B, C, and D to suppress the preexisting microflora in the mouth. Rats in groups A and C were subsequently inoculated with an S. sanguis strain, isolated from one of the rats, once a day for 5 d. Infection with P. gingivalis 381 was then carried out for 5 d in groups A, B, and E. Group F was not treated with doxycycline nor infected with bacteria and served as untreated control. Six weeks after the P. gingivalis inoculation, the rats were killed. Periodontal bone levels were assessed radiographically and morphometrically, and serum antibody against P. gingivalis 381 was determined by a fluorescence immunoassay. Periodontal bone support, determined radiographically, was reduced in group B (doxycycline-treated, P. gingivalis-inoculated) compared with the other groups. In contrast, the morphometric determination showed no differences between the groups. In group B antibody levels against two different P. gingivalis 381 cell surface antigens were significantly elevated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
226.
We recently showed that lipid assemblies comprised of a novel polycationic sphingolipid (ceramide carbamoyl-spermine, CCS) are an effective adjuvant/carrier when complexed with cholesterol (CCS/C) for influenza and other vaccines administered parenterally and intranasally (i.n.) in mice. Here we expand these studies to ferrets, an established model of influenza infection. We also address the question of why the CCS/C-based liposomal vaccine (also known as VaxiSome™) in mice is superior to vaccines based on liposomes of other lipid compositions (neutral, anionic or cationic). Ferrets immunized i.n. with CCS/C-influenza vaccine produced significantly higher hemagglutination inhibition (HI) antibody titers compared to ferrets immunized intramuscularly with the unadjuvanted influenza vaccine, indicating that the CCS/C-based vaccine is very immunogenic. Furthermore, the i.n. adjuvanted vaccine was shown to significantly reduce the severity of influenza virus infection in ferrets following homologous viral challenge as determined by weight loss, temperature rise and viral titer. No adverse reactions were observed. Pharmacokinetic and biodistribution studies following i.n. administration in mice of CCS/C-based vaccine showed that both the lipids and antigens are retained in the nose and lung for at least 24 h, and it appears that this retention correlates with the superior immunogenicity elicited by the adjuvanted vaccine formulation. The CCS lipid also increases production of cytokines (mainly IFN gamma, IL-2 and IL-12) and co-stimulatory molecules’ expression, which might further explain the robust adjuvantation of this liposome-based vaccine.  相似文献   
227.
Tuberoinfundibular peptide of 39 residues (TIP39) is the recently purified endogenous ligand of the previously orphan G-protein coupled parathyroid hormone 2 receptor (PTH2R). The TIP39–PTH2R system is a unique neuropeptide–receptor system whose localization and functions in the central nervous system are different from any other neuropeptides. TIP39 is expressed in two brain regions, the subparafascicular area in the posterior thalamus, and the medial paralemniscal nucleus in the lateral pons. Subparafascicular TIP39 neurons seem to divide into a medial and a lateral cell population in the periventricular gray of the thalamus, and in the posterior intralaminar complex of the thalamus, respectively. Periventricular thalamic TIP39 neurons project mostly to limbic brain regions, the posterior intralaminar thalamic TIP39 neurons to neuroendocrine brain areas, and the medial paralemniscal TIP39 neurons to auditory and other brainstem regions, and the spinal cord. The widely distributed axon terminals of TIP39 neurons have a similar distribution as the PTH2R-containing neurons, and their fibers, providing the anatomical basis of a neuromodulatory action of TIP39. Initial functional studies implicated the TIP39–PTH2R system in nociceptive information processing in the spinal cord, in the regulation of different hypophysiotropic neurons in the hypothalamus, and in the modulation of affective behaviors. Recently developed novel experimental tools including mice with targeted mutations of the TIP39–PTH2R system and specific antagonists of the PTH2R will further facilitate the identification of the specific roles of TIP39 and the PTH2R.  相似文献   
228.
This paper describes the effect on Sun Protection Factor (SPF) of the combination of inorganic and organic filters in sunscreen products as determined by an in vitro method. O/W emulsions containing inorganic filters, such as titanium dioxide and zinc oxide, combined with 18 EU-authorized UV-B organic filters were tested. SPF measurements were carried out using a spectrophotometer equipped with an integrating sphere.

This study observed a synergic effect when titanium dioxide was combined with either anisotriazine or octyldimethylPABA. The combination of zinc oxide with 11 UV-B organic filters also exhibited a similar synergy; however, the measured SPF was systematically lower than the protection factor achieved with titanium dioxide.  相似文献   

229.
Breast cancer is a heterogeneous disease and it is of importance to select patients with regard to different prognosis and treatment sensitivity to individualize treatment regimes. In this study we successfully adapted a protein extraction protocol from mRNA extracted tumor samples enabling two-dimensional gel electrophoresis (2-DE) analysis of samples previously analyzed by cDNA microarray. The aim was to find candidate proteins that distinguish breast cancer patients with or without recurrences after adjuvant CMF (cyclophosphamide, methotrexate and 5-FU) treatment within four years to follow-up. We identified several proteins distinguishing the recurrence group from the non-recurrence group, especially in the ER and PgR positive subgroup (n=7). The induced proteins were involved in translation/folding, iron ion binding, and protease inhibition, whereas proteins involved in signaling, ubiquitination, and splicing were decreased in expression. These results show that it is possible to use 2-DE to separate high abundant proteins in breast cancer tissue and to find discriminating proteins to identify patients with different prognosis after adjuvant CMF treatment.  相似文献   
230.
T-cell function is critical for murine cholesterol gallstone formation   总被引:3,自引:0,他引:3  
Maurer KJ  Rao VP  Ge Z  Rogers AB  Oura TJ  Carey MC  Fox JG 《Gastroenterology》2007,133(4):1304-1315
BACKGROUND & AIMS: The formation of cholesterol gallstones is a complex process involving contributions from genes and environmental factors. Although gallbladder inflammation is believed to be common during cholelithogenesis, the role of immunologic factors is unknown. METHODS: The role of adaptive immunity in cholesterol cholelithogenesis was analyzed utilizing immunocompetent Helicobacter spp.-infected and -uninfected BALB/c and congenic immunodeficient Rag2(-/-) (Rag) mice. Lymphocyte transfer studies were performed to determine which cellular subset was responsible for cholesterol gallstone formation. Also, gallbladder inflammation was quantified to determine the nature of the inflammatory response associated with cholelilithogenesis. RESULTS: When fed a lithogenic diet for 8 weeks, wild-type mice developed significantly more cholesterol gallstones (27%-80% prevalence) than Rag mice ( approximately 5%, P < .05). Helicobacter spp.-infected BALB/cJ mice displayed statistically significant increases in cholesterol gallstone prevalence compared with uninfected mice (81% vs. 39%; P < .05). Transfer of splenocytes or T lymphocytes to Rag2(-/-) mice increased stone prevalence markedly (26% and 40% respectively; P < .05), whereas transfer of B cells was not appreciably cholelithogenic (13%). The adaptive immune response increased the expression of gallbladder Muc genes and accumulation of mucin gel. In addition, T cells and cholesterol monohydrate crystals induced proinflammatory gene expression in the gallbladder, which likely contributes to gallbladder dysfunction. CONCLUSIONS: These studies indicate that T cells are critical in murine cholesterol cholelithogenesis. Furthermore, cholesterol monohydrate crystals induce expression of proinflammatory cytokines in a T-cell-dependent fashion. Acquired immunity and inflammation are likely to be crucial factors in cholesterol gallstone pathogenesis, rather then merely the result of cholelithogenesis.  相似文献   
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