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61.
Effect of Mycobacterium bovis BCG vaccination on Mycobacterium-specific cellular proliferation and tumor necrosis factor alpha production from distinct guinea pig leukocyte populations 总被引:3,自引:0,他引:3
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Lasco TM Yamamoto T Yoshimura T Allen SS Cassone L McMurray DN 《Infection and immunity》2003,71(12):7035-7042
In this study, we focused on three leukocyte-rich guinea pig cell populations, bronchoalveolar lavage (BAL) cells, resident peritoneal cells (PC), and splenocytes (SPC). BAL cells, SPC, and PC were stimulated either with live attenuated Mycobacterium tuberculosis H37Ra or with live or heat-killed virulent M. tuberculosis H37Rv (multiplicity of infection of 1:100). Each cell population was determined to proliferate in response to heat-killed virulent H37Rv, whereas no measurable proliferative response could be detected upon stimulation with live mycobacteria. Additionally, this proliferative capacity (in SPC and PC populations) was significantly enhanced upon prior vaccination with Mycobacterium bovis BCG. Accordingly, in a parallel set of experiments we found a strong positive correlation between production of antigen-specific bioactive tumor necrosis factor alpha (TNF-alpha) and prior vaccination with BCG. A nonspecific stimulus, lipopolysaccharide, failed to induce this effect on BAL cells, SPC, and PC. These results showed that production of bioactive TNF-alpha from mycobacterium-stimulated guinea pig cell cultures positively correlates with the vaccination status of the host and with the virulence of the mycobacterial strain. 相似文献
62.
Ivanka G. Popovi Lynne Katsikas Udo Müller Jovan S. Veli
kovi Horst Weller 《Macromolecular chemistry and physics.》1994,195(3):889-904
A completely new method of initiating the homogeneous radical polymerization of methyl methacrylate in bulk or in solution via the photogeneration of an electron hole pair in colloidal cadmium sulfide is presented. A polymerization mechanism involving an excited cadmium sulfide particle in both the initiation and termination steps is proposed. In the initiation a methyl methacrylate molecule is oxidized by a positive hole photogenerated in a CdS particle, which results in a novel chain-end structure of the poly(methyl methacrylate) (PMMA). Degradative chain transfer to reduced excited cadmium sulfide particles is responsible for chain termination. Thus, for the first time, a detailed polymerization mechanism in which all states of the polymerization, i.e., initiation, propagation, chain transfer and termination, is presented for the polymerization of vinyl monomers initiated by semiconductors. Thermogravimetry (TG) showed that the newly synthesized PMMA has greatly enhanced thermal stability when compared to normal radically prepared PMMA. In fact, the thermal stability approaches that of anionically prepared PMMA but is experimentally much easier to prepare. This technique enables the homogeneous embedding of CdS particles in a polymer matrix. 相似文献
63.
Kathleen J. Sawin Rachel H.F. Margolis Monique M. Ridosh Melissa H. Bellin Jason Woodward Timothy J. Brei Lynne Romeiser Logan 《Disability and health journal》2021,14(1):100940
BackgroundSelf-management is critical to optimizing the health of individuals with a chronic condition or disability and is, therefore, a central concept in individual and family-centered healthcare delivery. The purpose of this review is to report the state of the science of self-management for individuals with spina bifida (SB) from a lifespan perspective.ObjectiveThis review will summarize the (a) development and use of self-management skills and behaviors across the life span, (b) factors related to self-management behaviors, (c) development of generic or condition-specific measures of self-management used with a spina bifida population, and (d) development and/or outcomes of interventions to improve self-management in SB.MethodsThe search strategy was limited to primary research articles published between 2003 and 2019 and followed PRISMA guidelines. The databases searched included: PubMed, CINAHL, PsycINFO, Web of Science, Cochrane, and Google Scholar. Studies that addressed self-management concepts in individuals throughout the life span and published in English were included.ResultsThe search yielded 108 citations and 56 articles met inclusion/exclusion criteria. A systematic narrative synthesis was reported. The level of evidence identified was primarily Level III articles of good quality. Multiple demographic, environmental, condition and process factors were related to self-management behaviors. SB self-management instruments and intervention development and testing studies were identified.ConclusionsThis review provides a synthesis of the state of the science of self-management including factors related to self-management behaviors, preliminary evidence of instruments for use in SB, factors important to consider in the development and testing of future interventions, and gaps in the literature. 相似文献
64.
Shylaja Srinivasan Ling Chen Jennifer Todd Jasmin Divers Samuel Gidding Steven Chernausek Rose A. Gubitosi-Klug Megan M. Kelsey Rachana Shah Mary Helen Black Lynne E. Wagenknecht Alisa Manning Jason Flannick Giuseppina Imperatore Josep M. Mercader Dana Dabelea Jose C. Florez 《Diabetes》2021,70(4):996
The prevalence of type 2 diabetes in youth has increased substantially, yet the genetic underpinnings remain largely unexplored. To identify genetic variants predisposing to youth-onset type 2 diabetes, we formed ProDiGY, a multiethnic collaboration of three studies (TODAY, SEARCH, and T2D-GENES) with 3,006 youth case subjects with type 2 diabetes (mean age 15.1 ± 2.9 years) and 6,061 diabetes-free adult control subjects (mean age 54.2 ± 12.4 years). After stratifying by principal component–clustered ethnicity, we performed association analyses on ∼10 million imputed variants using a generalized linear mixed model incorporating a genetic relationship matrix to account for population structure and adjusting for sex. We identified seven genome-wide significant loci, including the novel locus rs10992863 in PHF2 (P = 3.2 × 10−8; odds ratio [OR] = 1.23). Known loci identified in our analysis include rs7903146 in TCF7L2 (P = 8.0 × 10−20; OR 1.58), rs72982988 near MC4R (P = 4.4 × 10−14; OR 1.53), rs200893788 in CDC123 (P = 1.1 × 10−12; OR 1.32), rs2237892 in KCNQ1 (P = 4.8 × 10−11; OR 1.59), rs937589119 in IGF2BP2 (P = 3.1 × 10−9; OR 1.34), and rs113748381 in SLC16A11 (P = 4.1 × 10−8; OR 1.04). Secondary analysis with 856 diabetes-free youth control subjects uncovered an additional locus in CPEB2 (P = 3.2 × 10−8; OR 2.1) and consistent direction of effect for diabetes risk. In conclusion, we identified both known and novel loci in the first genome-wide association study of youth-onset type 2 diabetes. 相似文献
65.
66.
67.
Carolina I. Galarreta Erin Hoyt Laura Forero Cynthia J. Curry Lynne M. Bird 《American journal of medical genetics. Part A》2023,191(11):2693-2702
VACTERL association is typically defined as the presence of three components among these birth defects: vertebral anomalies, anal atresia, cardiac anomalies, esophageal atresia/tracheoesophageal fistula (EA/TEF), renal anomalies, and limb defects. There is increasing recognition that VACTERL and other recurrent constellations of embryonic development often overlap clinically and might share pathogenesis. We conducted a comprehensive chart review of a large patient population with VACTERL association from two tertiary care centers in California. We included patients with incomplete VACTERL expression, which we denoted as “partial VACTERL” (pVACTERL). We assessed the occurrence of craniofacial (CF) findings in these two groups and the combined cohort. We collected data on potential risk factors and demographic information such as sex, Hispanic ancestry, pregnancy complications, and maternal age. The study included 409 participants, of whom 263 had VACTERL and 146 pVACTERL. CF abnormalities were found in 17.3% of VACTERL patients and 9.4% of pVACTERL patients. In the VACTERL group, ear anomalies were found in 10.2%, microtia in 5.9%, hearing loss (HL) in 13.90%, and orofacial clefts in 3.1%. In the pVACTERL group, ear anomalies were found in 7.2%, microtia in 5.0%, HL in 9.3%, and orofacial cleft in 2.2%. Maternal diabetes significantly increased the risk for HL in VACTERL (odds ratio [OR]: 3.71, 95% confidence interval [CI]: 1.5–7.3) and pVACTERL patients (OR: 6.7, 95% CI: 1.70–23.4). Poorly controlled maternal diabetes significantly increased the risk for all the outcomes in VACTERL patients including CF anomalies (OR: 4.2, 95% CI: 1.9–9.6), ear anomalies (OR: 4.7, 95% CI: 1.8–11.8), microtia (OR: 5.4, 95% CI: 1.7–16.6), and HL (OR: 8.1, 95% CI: 3.4–19.4). Twin status was significantly associated with the occurrence of microtia (p = 0.038) in VACTERL patients. Occurrence of CF features, particularly ear anomalies, microtia, and HL, might be considered as part of phenotypic diversity of VACTERL association. Diabetes and twinning might appear to play a role in increasing the risk for this phenotype in VACTERL association. 相似文献
68.
SV40 infection of quiescent mouse cells leads to a re-entry of the cells into the cell cycle and to cellular DNA synthesis. At about 2 hours after virus infection the p53 protein becomes detectable. By using the p53 specific monoclonal antibody PAb246 we were able to demonstrate that p53 is expressed in wild-type conformation. At late time after virus infection wild-type p53 is complexed to the SV40 large T antigen. SV40 infection of quiescent cells in the presence of an elevated level of cAMP does not result in cellular DNA synthesis and not in expression of elevated levels of p53 suggesting that p53 is implicated in stimulation of cellular DNA synthesis. Phosphorylation of p53 increases with time after SV40 infection of quiescent cells indicating that phosphorylation of p53 varies during cell cycle progression. 相似文献
69.
Infection of G(0) arrested NIH3T3 fibroblasts with SV40 induces quiescent cells to re-enter the cell cycle and to initiate cellular DNA synthesis. We analyzed the contribution of second messengers to the stimulation of cellular DNA synthesis by SV40 infection of quiescent cells. A rapid increase in the intracellular Ca2+ ion concentration and a decrease in the intracellular cAMP concentration was found. An elevated cAMP level is incompatible with the stimulation of cellular DNA synthesis by SV40 infection of quiescent cells. Thus, overcoming the cAMP sensitive restriction point seems to be an early event after SV40 infection of quiescent cells. These data demonstrate that signal transduction mechanisms are implicated in early response to SV40 infection of quiescent cells. 相似文献
70.
Sturm R Zhang W Schoenbaum M 《The journal of behavioral health services & research》1999,26(2):203-210
Substance abuse (SA) care has been excluded from recent federal and state legislation mandating equal benefits for mental health and medical care (parity), largely because of cost concerns. This article studies how many patients are affected by SA coverage limits and the likely implications of limits on insurance payments, using 1996–97 claims from 25 managed care plans with unlimited SA benefits. Changing even stringent limits on annual SA benefits has a small absolute effect on overall insurance costs under managed care, even though a large percentage of SA patients are affected. Removing an annual limit of $10,000 per year on SA care is estimated to increase insurance payments by about 6 cents per member per year, removing a limit of $1,000 increases payments by about $3.40. As long as care is comprehensively managed, parity for SA in employer-sponsored health plans is not very costly. 相似文献