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141.
A Pavlovian conditioning model of tolerance emphasizes that an association between predrug cues and the systemic effects of the drug contributes to tolerance. On the basis of this model, established tolerance should be attenuated by external inhibition, i.e., by presentation of a novel, extraneous stimulus. This prediction was evaluated in the present experiment. Rats that were so tolerant to the hypothermic effect of ethanol that they evidenced no drug-induced decrease in temperature were presented with a bright strobe light following ethanol administration. The light precipitated a large decrease in temperature in these rats. These results provide further evidence that tolerance to the hypothermic effect of ethanol is, in part, mediated by learning. 相似文献
142.
Jerome Seidenfeld Katherine A. Komar Marisa F. Naujokas Adrienne L. Block 《Cancer chemotherapy and pharmacology》1986,17(1):16-20
Summary We investigated the effect of pretreatment with difluoromethylornithine (DFMO), an ornithine decarboxylase inhibitor, on the cytocidal responses of four human adenocarcinoma cell lines to two alkylating and crosslinking agents: chlorambucil and N,N,N-triethylenethio-phosphoramide (thiotepa). The cell lines studied included HuTu-80 (duodenum), HT-29 (colon), ME-180 (cervix), and A-427 (lung). A 48- to 72-h pretreatment with DFMO reduced intracellular putrescine and spermidine contents to <10% and <1% of control levels. This treatment also caused a 30%–70% decline in spermine content. Survival of control and DFMO-pretreated cells after treatment with chlorambucil or thiotepa was measured by a plating efficiency assy. For three of the four lines studied, the DFMO-induced partial polyamine depletion significantly protected cells from the lethal effects of chlorambucil. In ME-180 cultures alone, DFMO pretreatment did not alter the cytocidal efficacy of chlorambucil. Addition of exogenous putrescine to cultures of HuTu-80, HT-29, or A-427 24 h after DFMO addition but 24 h before treatment with chlorambucil reversed the polyamine depletion and its protective effects on chlorambucil-induced cell kill. In contrast to the above observations, DFMO and partial polyamine depletion had no effect on cell survival after thiotepa treatment for any of the cell lines investigated.Abbreviations BCNU
1,3-bis (2-chloroethyl)-1-nitrosourea
- CENU
chloroethylnitrosourea
-
cis-Pt (II)
cis-diamminedichloroplatinum (II)
- DFMO
difluoromethylornithine
- ODC
ornithine decarboxylase
- PU
putrescine
- SD
spermidine
- SP
spermine thiotepa
-
N,N,N
triethylenethiophosphoramide
This investigation was supported in part by PHS grant no. CA-32758 awarded by the National Cancer Institute, DHHS; by grant no. 82-6 from the American Cancer Society, Ill. Div., Inc.; and by a Biomedical Research Support Grant to Northwestern University Medical School from the US PHS, NIH (RR-05370) 相似文献
143.
Shipkin Rebecca Blackledge Kristin Jacob Jane Bosoy Frederick Schertz Katherine Bachmann Gloria 《Maternal and child health journal》2022,26(5):1005-1014
Maternal and Child Health Journal - This study assessed whether the use of a peer-to-peer educational book, written and illustrated by women who experienced common mental disorders (CMDs) in the... 相似文献
144.
Tudor Kate Maloney Shannon Raja Anam Baer Ruth Blakemore Sarah-Jayne Byford Sarah Crane Catherine Dalgleish Tim De Wilde Katherine Ford Tamsin Greenberg Mark Hinze Verena Lord Liz Radley Lucy Opaleye Emerita Satiro Taylor Laura Ukoumunne Obioha C. Viner Russell Kuyken Willem Montero-Marin Jesus 《Prevention science》2022,23(6):934-953
Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such... 相似文献
145.
Stephanie Andraos Beatrix Jones Clare Wall Eric Thorstensen Martin Kussmann David Cameron-Smith Katherine Lange Susan Clifford Richard Saffery David Burgner Melissa Wake Justin OSullivan 《Nutrients》2021,13(3)
Scope: B vitamers are co-enzymes involved in key physiological processes including energy production, one-carbon, and macronutrient metabolism. Studies profiling B vitamers simultaneously in parent–child dyads are scarce. Profiling B vitamers in parent–child dyads enables an insightful determination of gene–environment contributions to their circulating concentrations. We aimed to characterise: (a) parent–child dyad concordance, (b) generation (children versus adults), (c) age (within the adult subgroup (age range 28–71 years)) and (d) sex differences in plasma B vitamer concentrations in the CheckPoint study of Australian children. Methods and Results: 1166 children (11 ± 0.5 years, 51% female) and 1324 parents (44 ± 5.1 years, 87% female) took part in a biomedical assessment of a population-derived longitudinal cohort study: The Growing Up in Australia’s Child Health CheckPoint. B vitamer levels were quantified by UHPLC/MS-MS. B vitamer levels were weakly concordant between parent–child pairs (10–31% of variability explained). All B vitamer concentrations exhibited generation-specificity, except for flavin mononucleotide (FMN). The levels of thiamine, pantothenic acid, and 4-pyridoxic acid were higher in male children, and those of pantothenic acid were higher in male adults compared to their female counterparts. Conclusion: Family, age, and sex contribute to variations in the concentrations of plasma B vitamers in Australian children and adults. 相似文献
146.
Kim Han Komudi Singh Matthew J. Rodman Shahin Hassanzadeh Yvonne Baumer Rebecca D. Huffstutler Jinguo Chen Julin Candia Foo Cheung Katherine E. R. Stagliano Mehdi Pirooznia Tiffany M. Powell-Wiley Michael N. Sack 《Nutrients》2021,13(5)
Intermittent fasting and fasting mimetic diets ameliorate inflammation. Similarly, serum extracted from fasted healthy and asthmatic subjects’ blunt inflammation in vitro, implicating serum components in this immunomodulation. To identify the proteins orchestrating these effects, SOMAScan technology was employed to evaluate serum protein levels in healthy subjects following an overnight, 24-h fast and 3 h after refeeding. Partial least square discriminant analysis identified several serum proteins as potential candidates to confer feeding status immunomodulation. The characterization of recombinant IGFBP1 (elevated following 24 h of fasting) and PYY (elevated following refeeding) in primary human CD4+ T cells found that they blunted and induced immune activation, respectively. Furthermore, integrated univariate serum protein analysis compared to RNA-seq analysis from peripheral blood mononuclear cells identified the induction of IL1RL1 and MFGE8 levels in refeeding compared to the 24-h fasting in the same study. Subsequent quantitation of these candidate proteins in lean versus obese individuals identified an inverse regulation of serum levels in the fasted subjects compared to the obese subjects. In parallel, IL1RL1 and MFGE8 supplementation promoted increased CD4+ T responsiveness to T cell receptor activation. Together, these data show that caloric load-linked conditions evoke serological protein changes, which in turn confer biological effects on circulating CD4+ T cell immune responsiveness. 相似文献
147.
Irina Maljkovic Berry Melanie C. Melendrez Simon Pollett Katherine Figueroa Darunee Buddhari Chonticha Klungthong Ananda Nisalak Michael Panciera Butsaya Thaisomboonsuk Tao Li Tyghe G. Vallard Louis Macareo In-Kyu Yoon Stephen J. Thomas Timothy Endy Richard G. Jarman 《Emerging infectious diseases》2021,27(6):1637
Dengue control approaches are best informed by granular spatial epidemiology of these viruses, yet reconstruction of inter- and intra-household transmissions is limited when analyzing case count, serologic, or genomic consensus sequence data. To determine viral spread on a finer spatial scale, we extended phylogenomic discrete trait analyses to reconstructions of house-to-house transmissions within a prospective cluster study in Kamphaeng Phet, Thailand. For additional resolution and transmission confirmation, we mapped dengue intra-host single nucleotide variants on the taxa of these time-scaled phylogenies. This approach confirmed 19 household transmissions and revealed that dengue disperses an average of 70 m per day between households in these communities. We describe an evolutionary biology framework for the resolution of dengue transmissions that cannot be differentiated based on epidemiologic and consensus genome data alone. This framework can be used as a public health tool to inform control approaches and enable precise tracing of dengue transmissions. 相似文献
148.
Gemma M. J. Taylor Katherine Sawyer David Kessler Marcus R. Munaf Paul Aveyard Alison Shaw 《Health expectations》2021,24(2):411
BackgroundTobacco smoking rates are significantly higher in people with common mental illness compared to those without. Smoking cessation treatment could be offered as part of usual outpatient psychological care, but currently is not.ObjectiveTo understand patient and health care professionals'' views about integrating smoking cessation treatment into outpatient psychological services for common mental illness.DesignQualitative in‐depth interviews, with thematic analysis.ParticipantsEleven Improving Access to Psychological Therapies (IAPT) psychological wellbeing practitioners (PWPs), six IAPT patients, and six stop smoking advisors were recruited from English smoking cessation, and IAPT services.ResultsPatients reported psychological benefits from smoking, and also described smoking as a form of self‐harm. Stop smoking advisors displayed therapeutic pessimism and stigmatizing attitudes towards helping people with mental illness to quit smoking. PWPs have positive attitudes towards smoking cessation treatment for people with common mental illness. PWPs and patients accept evidence that smoking tobacco may harm mental health, and quitting might benefit mental health. PWPs report expertise in helping people with common mental illness to make behavioural changes in the face of mood disturbances and low motivation. PWPs felt confident in offering smoking cessation treatments to patients, but suggested a caseload reduction may be required to deliver smoking cessation support in IAPT.ConclusionsIAPT appears to be a natural environment for smoking cessation treatment. PWPs may need additional training, and a caseload reduction. Integration of smoking cessation treatment into IAPT services should be tested in a pilot and feasibility study.Patient or public contributionService users and members of the public were involved in study design and interpretation of data. 相似文献
149.
150.
Effect of Condoms on Reducing the Transmission of Herpes Simplex Virus Type 2 From Men to Women 总被引:21,自引:1,他引:20
Wald Anna; Langenberg Andria G. M.; Link Katherine; Izu Allen E.; Ashley Rhoda; Warren Terri; Tyring Stephen; Douglas John M. Jr; Corey Lawrence 《JAMA》2001,285(24):3100-3106
Context Herpes simplex virus type 2 (HSV-2) is one of the most common sexually transmitted infections in the United States. No prospective study has shown the ability of condoms to reduce transmission of HSV-2. Objective To evaluate risk factors for HSV-2 acquisition and efficacy of condoms in prevention of HSV-2 transmission. Design Analysis of data from a randomized, double-blind, placebo-controlled trial conducted December 13, 1993, to June 28, 1996, of an ineffective candidate HSV-2 vaccine with 18 months of follow-up. Setting Eighteen clinical trial centers in the United States. Participants A total of 528 monogamous couples discordant for HSV-2 infection, including an HSV-2susceptible population of 261 men and 267 women. Main Outcome Measure Acquisition of HSV-2 infection by susceptible partners, compared with those remaining free of HSV-2 with regard to demographic characteristics, sexual activity, and condom use. Results Twenty-six women (9.7%) vs 5 men (1.9%) acquired HSV-2, for a rate per 10 000 sex acts (episodes of sexual intercourse) of 8.9 vs 1.5, respectively (P<.001). In multivariable analysis, younger age (adjusted hazard ratio [HR] per 5 years, 1.57; 95% confidence interval [CI], 1.22-2.04), seropositivity for HSV-1 and HSV-2 vs HSV-2 alone in the source partner (adjusted HR, 2.34; 95% CI, 1.14-4.82), and more frequent sexual activity (adjusted HR per additional sex act per week, 1.10; 95% CI, 1.01-1.19) were associated with higher risk of HSV-2 acquisition. Condom use during more than 25% of sex acts was associated with protection against HSV-2 acquisition for women (adjusted HR, 0.085; 95% CI, 0.01-0.67) but not for men (adjusted HR, 2.02; 95% CI, 0.32-12.50). Risk of HSV-2 transmission declined from 8.5 per 100 person-years in the initial 150-day interval to 0.9 per 100 person-years in the final 150-day interval (P = .002 for trend), concurrent with a decrease in sexual activity and proportion of sex acts occurring when the source partner had genital lesions. Conclusions Condom use offers significant protection against HSV-2 infection in susceptible women. Changes in sexual behavior, correlated with counseling about avoiding sex when a partner has lesions, were associated with reduction in HSV-2 acquisition over time. These data suggest that identification of discordant couples can reduce transmission of HSV-2, especially for heterosexual couples in which the male partner has HSV-2 infection. 相似文献