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11.
Karina R B Bastos Renato Barboza Luiz Sardinha Momtchilo Russo José M Alvarez Maria Regina D'Império Lima 《Journal of interferon & cytokine research》2007,27(5):399-410
Besides the established role of interleukin-12 (IL-12) and IL-18 on interferon-gamma (IFN-gamma) production by natural killer (NK), T, and B cells, the effects of these cytokines on macrophages are largely unknown. Here, we investigated the role of IL-12/IL-18 on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by CD11b(+) adherent peritoneal cells, focusing on the involvement of endogenously produced IFN-gamma. C57BL/6 cells released substantial amounts of NO when stimulated with IFN-gamma or lipopolysaccharide (LPS), but failed to respond to IL-12 or IL-18 or both. However, IL-12/IL-18 pretreatment was able to program these cells to release 6-8-fold more NO and TNF-alpha in response to LPS or Trypanosoma cruzi stimulation, with NO levels directly correlating with macrophage resistance to intracellular parasite growth. Analysis of IL-12/IL-18-primed cells from mice deficient in IFN-gamma, IFNGR, and IFN regulatory factor-1 (IRF-1) revealed that these molecules were essential for LPS-induced NO release, but TNF-alpha production was IFN-gamma independent. Conversely, the myeloid differentiation factor 88 (MyD88)-dependent pathway was indispensable for IL-12/IL-18-programmed LPS-induced TNF-alpha production, but not for NO release. Contaminant T and NK cells largely modulated the IL-12/IL-18 programming of LPS-induced NO response through IFN-gamma secretion. Nevertheless, a small population of IFN-gamma(+) cells with a macrophage phenotype was also identified, particularly in the peritoneum of chronically T. cruzi-infected mice, reinforcing the notion that macrophages can be an alternative source of IFN-gamma. Taken together, our data contribute to elucidate the molecular basis of the IL-12/IL-18 autocrine pathway of macrophage activation, showing that endogenous IFN-gamma plays an important role in programming the NO response, whereas the TNF-alpha response occurs through an IFN-gamma-independent pathway. 相似文献
12.
Taylor S Thordarson DS Maxfield L Fedoroff IC Lovell K Ogrodniczuk J 《Journal of consulting and clinical psychology》2003,71(2):330-338
The authors examined the efficacy, speed, and incidence of symptom worsening for 3 treatments of posttraumatic stress disorder (PTSD): prolonged exposure, relaxation training, or eye movement desensitization and reprocessing (EMDR; N = 60). Treaments did not differ in attrition, in the incidence of symptom worsening, or in their effects on numbing and hyperarousal symptoms. Compared with EMDR and relaxation training, exposure therapy (a) produced significantly larger reductions in avoidance and reexperiencing symptoms, (b) tended to be faster at reducing avoidance, and (c) tended to yield a greater proportion of participants who no longer met criteria for PTSD after treatment. EMDR and relaxation did not differ from one another in speed or efficacy. 相似文献
13.
Karina R B Bastos Renato Barboza Rosa M Elias Luiz R Sardinha Marcos G Grisotto Cláudio R F Marinho Gustavo P Amarante-Mendes José M Alvarez Maria Regina D'Império Lima 《Journal of interferon & cytokine research》2002,22(12):1191-1199
Aiming to clarify the role of endogenous interleukin-12 (IL-12) in protective immunity against blood stages of Plasmodium chabaudi chabaudi (AS), we evaluated the course of infection in IL-12p40 gene knockout (IL-12p40KO) and wild-type (WT) C57BL/6 mice, focusing (1) on the ability of T cells to develop adequate type 1 responses and (2) on the potentiality of macrophages to respond to parasites, interferon-gamma (IFN-gamma), or both. We observed that IL-12p40KO mice develop significantly higher parasitemias during the acute infection, although mice from both groups clear the parasites within a month and similarly eliminate a secondary challenge. Thus, fully protective immunity to P. c. chabaudi can be generated in the absence of IL-12. However, this cytokine may promote parasite control during the early phase of infection. The increased acute parasitemia of IL-12p40KO mice was associated with both impaired IFN-gamma and nitric oxide (NO) response by spleen cells. Because stimulation with recombinant IFN-gamma (rIFN-gamma) failed to improve the NO response in IL-12p40KO macrophages, we investigated whether these cells have an intrinsic defect. Analysis of peritoneal macrophages revealed that IL-12p40KO cells produce higher levels of transforming growth factor-beta1 (TGF-beta1) compared with WT cells and respond to infected erythrocytes or rIFN-gamma by releasing little NO. Moreover, IL-12p40KO macrophages had a severely impaired ability to internalize opsonized infected erythrocytes, suggesting that the low effector profile assumed by these cells may compromise antibody-mediated immunity. Taken together, our results support the idea that the absence of IL-12p40 not only affects IFN-gamma production but also has deep consequences in macrophage effector functions that may contribute to exacerbation of the early phase of P. c. chabaudi malaria. 相似文献
14.
A panel of six monoclonal antibodies (mAbs) against a grouper iridovirus (SGIV) were produced by immunization of Balb/c mice with purified virus preparations. Isotyping test revealed all the mAbs were IgG1. None of the mAbs possessed the ability to neutralize SGIV in cell cultures. Western blot showed that 4 mAbs reacted with 2 SGIV proteins at molecular mass of approximately 100 and 117 kDa in gradient-purified virus. Immunofluorescent studies showed that the two specific viral proteins VP100 and VP117 were localized within virus assembly sites in the cytoplasm of SGIV-infected grouper cells (GP). Fractionations of the iridovirus in a 20-60% sucrose gradient were detected successfully by all the six mAbs using immunodot blot. An antigen-capture enzyme-linked immunosorbent assay (ELISA) system, based on the use of mAb 7E11 for capture and a rabbit polyclonal antibody to SGIV for detection was developed. SGIV antigen was detected in gradient-purified virus and virus-infected grouper blood. These novel mAbs will facilitate the development of more specific and standardized diagnostic techniques for marine fish iridovirus. 相似文献
15.
Immune responses induced by the Leishmania (Leishmania) donovani A2 antigen,but not by the LACK antigen,are protective against experimental Leishmania (Leishmania) amazonensis infection 下载免费PDF全文
Coelho EA Tavares CA Carvalho FA Chaves KF Teixeira KN Rodrigues RC Charest H Matlashewski G Gazzinelli RT Fernandes AP 《Infection and immunity》2003,71(7):3988-3994
Leishmania amazonensis is one of the major etiologic agents of a broad spectrum of clinical forms of leishmaniasis and has a wide geographical distribution in the Americas, which overlaps with the areas of transmission of many other Leishmania species. The LACK and A2 antigens are shared by various Leishmania species. A2 was previously shown to induce a potent Th1 immune response and protection against L. donovani infection in BALB/c mice. LACK is effective against L. major infection, but no significant protection against L. donovani infection was observed, in spite of the induction of a potent Th1 immune response. In an attempt to select candidate antigens for an American leishmaniasis vaccine, we investigated the protective effect of these recombinant antigens (rLACK and rA2) and recombinant interleukin-12 (rIL-12) against L. amazonensis infection in BALB/c mice. As expected, immunization with either rA2-rIL-12 or rLACK-rIL-12 induced a robust Th1 response prior to infection. However, only the BALB/c mice immunized with rA2-rIL-12 were protected against infection. Sustained gamma interferon (IFN-gamma) production, high levels of anti-A2 antibodies, and low levels of parasite-specific antibodies were detected in these mice after infection. In contrast, mice immunized with rLACK-rIL-12 displayed decreased levels of IFN-gamma and high levels of both anti-LACK and parasite-specific antibodies. Curiously, the association between rA2 and rLACK antigens in the same vaccine completely inhibited the rA2-specific IFN-gamma and humoral responses and, consequently, the protective effect of the rA2 antigen against L. amazonensis infection. We concluded that A2, but not LACK, fits the requirements for a safe vaccine against American leishmaniasis. 相似文献
16.
Motivation to provide care is a significant predictor of informal caregiving among family caregivers of persons with dementia. Adequate support is an important source of help and relief to caregivers, but fragmentation of dementia care services is common and better ways of supporting these caregivers are needed. Knowledge of adult-child caregivers' motivation and how this motivation is influenced by community healthcare services is lacking. The aim of this study is therefore to describe and explore adult children's experiences with community healthcare services for their home-dwelling parent with dementia and how these influence their caregiver motivation. The study applied a qualitative design based on three focus group interviews with 15 of these caregivers (40–69 years) in Norway in 2017. The study results indicate three categories supporting adult children's sustained motivation as caregivers: (a) caregivers prioritize their parent's need for healthcare services over their own need for support; (b) caregivers need acknowledgement through respect and involvement; and (c) caregivers need timely information and competence as the dementia progresses. To stimulate collaboration among adult-child caregivers, their parents with dementia, and community healthcare services, we claim that a relationship-centred care framework could be emphasised as a way of supporting sustained motivation among caregivers to parents with dementia as part of community healthcare services. 相似文献
17.
Power Thomas G. Garcia Karina Silva Martinez AnaMaria Diaz Parker Louise A. Hidalgo-Mendez Jackelyn Ramos Guadalupe 《Prevention science》2022,23(6):1018-1028
Prevention Science - “Madres Apoyando el Desarrollo Emocional de Sus Hijos” (“Mothers Supporting the Emotional Development of Their Children”) is a parenting... 相似文献
18.
Diana Gabriela Figueroa-Pia Jorge Luis Chvez-Servín Karina de la Torre-Carbot María del Carmen Caamao-Prez Gabriela Lucas-Deecke Patricia Roitman-Genoud Laura Regina Ojeda-Navarro 《Nutrition Research And Practice》2021,15(2):235
BACKGROUND/OBJECTIVESIncreasing the consumption of vegetables and fruits in Mexico remains a challenge. Promoting sustainable food production systems through schools may be an effective way to educate young people about food and nutrition issues. A study of nutritional education in adolescents, based on the school garden, is necessary in order to evaluate its effects on the consumption of fruits and vegetables among middle- and upper-income segments of the population. The objective of this study was to evaluate the effect of an educational intervention, accompanied by a school garden as an educational teaching tool, to improve vegetable and fruit consumption by Mexican teenagers attending a private middle/high school.SUBJECTS/METHODSTeenagers between 12 and 18 years of age (n = 126) attending a private middle/high school in Queretaro, Mexico participated in a 3-arm, controlled, comparative impact study using a vegetable and fruit consumption frequency questionnaire, food consumption diaries, a psychosocial factor assessment questionnaire of vegetable and fruit consumption, and structured interviews. The participants were randomized into 3 experimental groups: 1) food education + school garden (FE + SG), 2) FE only, and 3) control group (CG).RESULTSThe FE + SG and FE groups significantly increased the frequency and daily intake of vegetables and fruits compared to the CG. The FE + SG group showed greater understanding of, reflection upon, and analysis of the information they received about vegetable and fruit consumption, as well as a greater willingness to include these in their daily diet.CONCLUSIONSFE accompanied by a SG as a teaching tool is more effective at promoting vegetable and fruit consumption than either education alone or control in teenagers in middle-upper income segments of the population. 相似文献
19.
Dietermann Karina Winter Vera Schneider Udo Schreyögg Jonas 《The European journal of health economics》2021,22(5):833-846
The European Journal of Health Economics - The goal of this study is to provide empirical evidence of the impact of nurse staffing levels on seven nursing-sensitive patient outcomes (NSPOs) at the... 相似文献
20.
Barroso Rosmeire Aparecida Navarro Ricardo Tim Carla Roberta de Paula Ramos Lucas de Oliveira Luciane Dias Araki Ângela Toshie Fernandes Karina Gonzales Camara Macedo Daniela Assis Lívia 《Lasers in medical science》2021,36(6):1235-1240
Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial... 相似文献