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101.
Boughton-Smith Nigel K. Deakin Angela M. Whittle Brendan J. R. 《Inflammation research》1992,36(1):C3-C9
The actions of nitric oxide (NO) on the acute gastrointestinal damage induced by platelet-activating factor (PAF) have been investigated in the rat.S-nitroso-N-acetyl penicillamine, which spontaneously generates NO, dose-dependently inhibited PAF-induced gastrointestinal plasma leakage, a measure of the initiation of vascular damage. The inhibitor of NO synthase,NG-monomethyl-l-arginine substantially potentiated gastrointestinal damage and plasma leakage induced byE. coli endotoxin, but had no effect on that induced by intravenous infusion of PAF.Endogenous NO may thus have a protective role in the gastrointestinal vascular that can be mimicked by generators of NO. The protection afforded by endogenous NO may, however, be dependent on the nature of the inflammatory stimulus used to induce gastrointestinal damage. 相似文献
102.
The rate of clearance of inhaled 99mTc-pentetate aerosols has been used as an indicator of pulmonary epithelial "permeability" in human and animal studies. In order to evaluate this technique further, groups of eight male ferrets (Mustela putorius furo) were given acute exposures to aerosols of CdCl2 or NaCl via endotracheal tube. Serial evaluations of the thoracic clearance rate of inhaled 99mTc-pentetate aerosols (MMAD = 0.6 microns, sigma g = 1.6) were made before exposure and at fixed time points after toxicant exposure (3 or 6, 24, 48 h, and 5 days after CdCl2). These serial evaluations of 99mTc-pentetate thoracic clearance were conducted at three cadmium intake levels (3, 10, and 30 min exposure to 10 mg/m3 CdCl2) in order to evaluate possible dose-related response relationships. The rate of thoracic clearance of Tc-pentetate was observed to be slowed at 3 h after exposure to CdCl2 aerosol and subsequently increased to well above control rates. The time sequence observed strongly suggests that increased Tc-pentetate clearance rates are indicative of a tissue response or repair process, rather than acute lung injury. Tracheal epithelial penetration of macromolecular tracers was not observed to increase in histological evaluations following serial sacrifice. 相似文献
103.
Effect of moderate exercise on salivary immunoglobulin A and infection risk in humans 总被引:3,自引:0,他引:3
Klentrou P Cieslak T MacNeil M Vintinner A Plyley M 《European journal of applied physiology》2002,87(2):153-158
The incidence of upper respiratory tract infections (URTI) and salivary immunoglobulin A concentrations [IgAs] of nine individuals were examined during 12 weeks of moderate exercise training, and compared to ten sedentary controls.
Changes in maximal oxygen uptake were assessed at initial, mid-point and final evaluations (T1–3), while changes in [IgAs] and salivary immunoglobulin concentration-salivary albumin concentration ratio ([IgAs]:[Albs]) were monitored at T1 and T3. During the 12 week period, symptoms of URTI were self-recorded daily. During the period of
training the level of fitness significantly increased (P<0.05) in the exercise group. The number of days recording symptoms of influenza, but not of cold, and total light URTI symptoms was significantly reduced in the exercise group during the last weeks of training. A significant increase in
[IgAs] and in [IgAs]:[Albs] was found in the exercise group after training. Both [IgAs] and [IgAs]:[Albs] were significantly related to the number of days showing symptoms of influenza (P<0.01) and the total number of days of sickness (P<0.05). These data provide quantitative support for the belief that regular, moderate exercise results in an increased [IgAs] at rest and [IgAs]:[Albs], which may contribute to a decreased risk of infection.
Electronic Publication 相似文献
104.
Karen W. Gripp Lindsey A. Morse Marni Axelrad Kathryn C. Chatfield Aaron Chidekel William Dobyns Daniel Doyle Bronwyn Kerr Angela E. Lin David D. Schwartz Barbara J. Sibbles Dawn Siegel Suma P. Shankar David A. Stevenson Mihir M. Thacker K. Nicole Weaver Sue M. White Katherine A. Rauen 《American journal of medical genetics. Part A》2019,179(9):1725-1744
Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition. 相似文献
105.
Koc S Kather A Markert UR Dürst M Schneider A Kaufmann AM 《American journal of reproductive immunology (New York, N.Y. : 1989)》2003,50(3):243-253
PROBLEM: The choriocarcinoma cell line Jeg3 suppresses immunity in vitro by secretion of soluble factors like leukemia inhibitory factor suppressing leukocyte activation. The cells lack expression of classical human leukocyte antigen (HLA)-A and -B alleles but express some HLA-C, and non-classical HLA-G and -E. Upon binding to killing inhibitory receptor on natural killer (NK) cells, HLA-G prevents activation of cytolytic activity. We investigated whether Jeg3 cells are capable of immune stimulation after complementation with classical HLA and T cell costimulatory signal CD80. METHOD OF STUDY: Jeg3 cells were transduced to express HLA-A*0201 and/or CD80. Parental Jeg3 or transfectants Jeg3-A2, Jeg3-CD80 or Jeg3-CD80-A2 were used to stimulate allogeneic resting and activated peripheral blood lymphocytes (PBL). The different cell lines were loaded with a HLA-A2-restricted Epstein-Barr virus (EBV) recall antigen peptide epitope and antigen presenting ability was examined. T cell lines specific for Jeg3 and transfectants were generated from HLA-A2 matched and nonmatched donors and compared for expansion, phenotypes and cytolytic activity. RESULTS: While all Jeg3 cell lines induced only marginal proliferation of resting T cells, phytohemagglutinin (PHA)-activated T cells were stimulated by CD80 or CD80-A2 expressing Jeg3. Only the transfectant Jeg3-CD80-A2 was capable of specific T cell stimulation by EBV recall antigen presentation. T cell lines of HLA-A2 non-matched donors stimulated with the Jeg3 transfectants showed significant expansion only when HLA-A2 and the costimulus CD80 were present. T cells from HLA-A2 positive donors did not expand significantly or differentially. No NK cells grew under any condition. In Jeg3-CD80-A2 stimulated T cells lines CD8+ cells expanded preferentially. These T cells exerted cytolytic activity toward all Jeg3 cell lines. CONCLUSION: Our data suggest that, in spite of immunosuppressive mechanisms, proliferative and cytolytic T cell responses are induced by Jeg3 cells when classical HLA- and/or costimulatory signals are present on the cells. 相似文献
106.
Expression of human immunodeficiency virus type 1gag gene using genetically engineered herpes simplex virus type 1 recombinants 总被引:1,自引:0,他引:1
Angela Rösen-Wolff Karl Raab Lothar Zöller Gholamreza Darai Josef Eberle Friedrich Deinhardt 《Virus genes》1990,4(4):325-337
Infectious herpes simplex virus type 1 (HSV-1) recombinants were constructed by inserting the cDNA sequence of the human immunodeficiency virus type 1 (HIV-1)gag gene (from nucleotide position 675 [SacI] to 3859 [Asp 718] of the cDNA sequences of HIV-1 strain BH-10) within the DNA sequences of theBamHI DNA fragment B of the genome of an apathogenic HSV-1 strain HFEM. This HSV-1 strain possesses a 4.1-kbp deletion within theBamHI DNA fragment B between 0.762 and 0.789 map units of the viral genome, which allows the insertion of at least 4 kbp of foreign genetic material into this particular region. The DNA sequences of the immediate early promoter (IE4) of HSV-1 that were inserted upstream from thegag gene were used as a promoter. The screening of 205 virus stocks derived from individual plaques revealed that 46 recombinant viruses harbor HIV-1gag-specific DNA sequences. However, it was found that only six of the recombinant viruses are able to express thegag gene product of HIV-1. This indicates that the ratio of the positive recombination events is about 2.9%. 相似文献
107.
The reactivity of vesicular stomatitis virus (VSV) with kethoxal can be appreciably altered by treatment with 1-guanyl-3, 5-dimethyl pyrazole nitrate (GDMP) and proteolytic enzymes. Pretreatment of purified VSV with GDMP or proteolytic enzymes markedly reduced the effectiveness of kethoxal as a virucide. The rate of neutralizability of GDMP- and trypsin-treated viruses by specific antiserum differed from that of controls. 相似文献
108.
Presumptive Mosaic Partial Trisomy Associated with Congenital Anomalies and Mental Deficiency 下载免费PDF全文
Angela M. Vianna-Morgante Wanderley M. Domingues Claudio C. Ortega Sanae Kasahara 《Journal of medical genetics》1974,11(1):104-108
The case of a mentally retarded patient with congenital anomalies not typical of any known chromosome unbalance is reported. In his karyotype, 40·6% of the cells were normal, while 59·4% had a missing G and an almost metacentric marker longer than an F chromosome. The abnormal cell line was interpreted as resulting from a chromatid translocation involving the short arm of a No. 22 and a segment from an unidentified chromosome. The translocation probably took place after the first cell division and was followed by segregation of the translocated chromatids. Other obvious hypotheses were excluded by the study of fluorescence patterns. The patient's clinical features may be due to a partial autosomal trisomy. 相似文献
109.
Margaret?Holmes-RovnerEmail author Sue?Stableford Angela?Fagerlin John?T?Wei Rodney?L?Dunn Janet?Ohene-Frempong Karen?Kelly-Blake David?R?Rovner 《BMC medical informatics and decision making》2005,5(1):16
Background
Decision aids (DA) to assist patients in evaluating treatment options and sharing in decision making have proliferated in recent years. Most require high literacy and do not use plain language principles. We describe one of the first attempts to design a decision aid using principles from reading research and document design. The plain language DA prototype addressed treatment decisions for localized prostate cancer. Evaluation assessed impact on knowledge, decisions, and discussions with doctors in men newly diagnosed with prostate cancer. 相似文献110.
Angela Hong Stewart Davies Graham Stevens C Soon Lee 《Applied immunohistochemistry & molecular morphology》2004,12(1):26-30
The anatomic distribution and rate of progression vary significantly between acquired immunodeficiency syndrome (AIDS)-related Kaposi sarcoma (KS) and classic KS. The reasons are unclear, but cyclin D1 overexpression is associated with tumor progression in other malignancies. Cyclin D has an important regulatory role in the progression of cell cycle at the G1-S phase due to its effect in phosphorylating the retinoblastoma gene product. Forty-one paraffin-embedded surgical specimens (31 AIDS-related, 10 classic) were examined using streptavidin-biotin-peroxidase immunohistochemistry with monoclonal antibody to cyclin D1. A scoring system based on the intensity and extent of staining was used. The correlations among cyclin D1 expression and clinicopathologic parameters were statistically analyzed. Cyclin D1 overexpression was found in 29% (12/41) of all KS cases. There was a strong correlation between cyclin D1 overexpression and pathologic stage (0% in patch stage, 13% in plaque stage, 50% in nodular stage; P = 0.0017). Classic KS lesions had a higher incidence of cyclin D1 overexpression than AIDS-related lesions (70% vs 16%, P = 0.001). Cyclin D1 overexpression was detected in 78% of the classic nodular lesions and 31% of the AIDS-related nodular lesions (P = 0.03). On multivariate analysis, negative human immunodeficiency virus status (P = 0.001) and nodular lesions (P = 0.007) were strong predictors of cyclin D1 overexpression. Age, gender, recurrence of the tumor, multiplicity, and site of the lesions hold no statistically significant association with cyclin D1 expression on multivariate analysis. In summary, cyclin D1 overexpression was more prevalent in classic lesions and more advanced nodular stage. These findings raise the possibility of a different pathogenetic mechanism in the progression of AIDS-related KS and classic KS. 相似文献