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61.
Modifications induced by dietary lipid source in adipose tissue phospholipid fatty acids and their consequences in lipid mobilization 总被引:1,自引:0,他引:1
Portillo MP Tueros AI Perona JS Ruiz-Gutiérrez V Torres I Macarulla MT 《The British journal of nutrition》1999,82(4):319-327
The aim of the present work was to assess the influence of dietary lipid source on fatty acid phospholipid profiles and on lipid mobilization. Forty male Wistar rats were divided into four groups and fed on high-fat diets which provided olive oil, sunflower oil, palm oil or beef tallow. All rats received the same amount of energy to avoid hyperphagia and differences in energy intake among groups. Phospholipid fatty acids were determined by GC. Lipolysis was stimulated in subcutaneous and perirenal isolated adipocytes by several lipolytic agents, and assessed by the determination of released glycerol. After 4 weeks of feeding, differences in body and adipose tissue weights were not observed. Dietary regimens caused great changes in adipose tissue phospholipid composition: rats fed on palm oil and beef tallow had higher concentrations of saturated fatty acids and animals fed on olive oil or sunflower oil had greater amounts of oleic and linoleic acids, respectively. These modifications did not lead to important changes in adipocyte lipolysis. Significant differences were only observed between palm-oil- and beef-tallow-fed groups when lipolysis was stimulated by isoproterenol in subcutaneous adipocytes. The fact that our feeding protocol did not induce differences in fat accumulation among groups avoids misinterpretations due to adiposity changes. The differences observed between both saturated-fat-fed groups, therefore, should only be attributable to dietary lipids. Despite this effect, the data from this work indicate that some diet-induced changes in adipose tissue fatty acid composition may have little effect on overall function. 相似文献
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The development of B cells requires the expression of an antigen receptor at distinct points during maturation. The Ig-alpha/beta heterodimer signals for these receptors, and mice harboring a truncation of the Ig-alpha intracellular domain (mb-1(delta(c)/delta(c)) have severely reduced peripheral B cell numbers. Here we report that immature mb-1(delta(c)/delta(c) B cells are activated despite lacking a critical Ig-alpha-positive signaling motif. As a consequence of abnormal activation, transitional immature IgMhighIgDlow B cells are largely absent in mb-1delta(c)/delta(c) mutants, accounting for the paucity of mature B cells. Thus, Ig-alpha cytoplasmic tail truncation yields an antigen receptor complex on immature B cells that signals constitutively. These data illustrate a role for Ig-alpha in negatively regulating antigen receptor signaling during B cell development. 相似文献
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Quiralte J Sánchez-García F Torres MJ Blanco C Castillo R Ortega N de Castro FR Pérez-Aciego P Carrillo T 《The Journal of allergy and clinical immunology》1999,103(4):685-689
BACKGROUND: Several HLA alleles have been associated with asthma induced by nonsteroidal anti-inflammatory drugs (NSAIDs). The existence of HLA markers linked to other NSAID-induced reactions, such as cutaneous and anaphylactoid reactions, has not been established. OBJECTIVE: The purpose of our work was to study the HLA-DRB1 and HLA-DQB1 alleles in patients with cutaneous and anaphylactoid reactions caused by NSAIDs. METHODS: We have analyzed 114 HLA DRB1 and 26 HLA-DQB1 alleles in 21 patients with anaphylactoid reactions caused by NSAIDs, 47 patients who had exclusively cutaneous reactions during single-blind, placebo-controlled oral challenges with NSAIDs, and 167 tolerant control subjects (29 of whom had also had an IgE-mediated anaphylaxis to different agents). HLA-DRB1 and HLA-DQB1 alleles were typed by the polymerase chain reaction sequence-specific primers method with genomic DNA. RESULTS: The frequency of HLA-DR11 alleles was 58.8% in the anaphylactoid reaction group, compared with 15.9% in the NSAID-tolerant healthy control subjects (OR, 7:3; 95% confidence interval, 2.8-19.0; P <.02) and 6.3% in the group of the patients with a tolerance for NSAIDs and with IgE-mediated anaphylaxis (OR, 18.75; 95% confidence interval, 4.3-81.1; P <.004). No differences were observed among HLA-DR11 alleles analyzed. There were no significant HLA-DQB1 associations with NSAID-induced anaphylactoid reactions. Patients with cutaneous reactions had HLA frequencies that did not differ significantly from the tolerant control subjects. CONCLUSION: The HLA-DRB1*11 alleles showed a positive association with NSAID-induced anaphylactoid reactions. 相似文献
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Marcelo Borges Cavalcante Candice Torres de Melo Bezerra Cavalcante Ana Catherine Sampaio Braga Dennyse Araújo Andrade Mariana Albuquerque Montenegro Paula Andrade Neiva Santos Paula Vitria Pereira Motoyama Marcelo Gondim Rocha Luciana Azr Dib Edward Araujo Júnior 《Geburtshilfe und Frauenheilkunde》2021,81(1):46
In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding 相似文献
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Personality and clinical predictors of recurrence of depression 总被引:3,自引:0,他引:3
Berlanga C Heinze G Torres M Apiquián R Caballero A 《Psychiatric services (Washington, D.C.)》1999,50(3):376-380
OBJECTIVE: To help clinicians more accurately predict outcomes of treatment for depression, variables associated with recurrence of depression in the year after treatment were examined in a group of patients who completed treatment for an index episode of depression. METHODS: Forty-two depressed patients who participated in a double-blind pharmacological treatment study were followed for one year after treatment was discontinued. Length of treatment for the index episode was determined by clinicians and ranged from eight to 76 consecutive weeks. Eighteen patients who had a recurrent episode (43 percent) and 24 patients who did not (57 percent) were compared on sociodemographic and clinical variables, including scores on the Eysenck Personality Questionnaire (EPQ). RESULTS: A combination of three variables predicted recurrence of depression in 90 percent of cases. They were an elevated EPQ score on the neuroticism subscale, a short duration of treatment of the index episode, and a slow onset of response to treatment of the index episode. CONCLUSIONS: The findings suggest that personality traits, treatment duration, and variations in response to treatment might have an impact on long-term treatment outcome. Clinicians should consider these factors when making treatment decisions for depressed patients. 相似文献
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