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101.
Roger Suau Marta Vidal Ruth Aguilar Gemma Ruiz-Olalla Miquel Vázquez-Santiago Chenjerai Jairoce Augusto J. Nhabomba Ben Gyan David Dosoo Kwaku Poku Asante Seth Owusu-Agyei Joseph J. Campo Luis Izquierdo David Cavanagh Ross L. Coppel Virander Chauhan Evelina Angov Sheetij Dutta Carlota Dobaño 《Vaccine》2021,39(4):687-698
BackgroundThe evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection.MethodsNinety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01E phase 3 clinical trial who received 3 doses of RTS,S/AS01E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay.ResultsRTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses.ConclusionsRTS,S/AS01E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01E immunization is necessary for the design of improved second-generation vaccines.Clinical trial registration: ClinicalTrials.gov: NCT008666191. 相似文献
102.
Ruth Naughton-Doe MSc PhD Ailsa Cameron MSc John Carpenter B.Sc. Cert. App. Soc. Studies C.Q.S.W. C.Psychol. AFBPsS DSc 《Health & social care in the community》2021,29(5):1285-1295
This paper explores the potential contribution of timebanking, an innovative volunteering scheme, to the co-production of preventive social care with adults in England. Interest in volunteering in social care has increased as one proposed solution to the international crisis of a rising demand for services in juxtaposition with decreased resources. Volunteering has been particularly promoted in preventive services that prevent or delay care needs arising. Despite sustained interest in volunteering and co-production in social care, little is known about how theory translates into practice. Reporting implementation data from a Realistic Evaluation of six case studies in England, this paper explores one volunteering scheme, timebanking. The research explores how timebanks were working, what contribution they can make to adult social care, and whether they are an example of co-production. Data collected included interviews, focus groups or open question responses on surveys from 84 timebank members, and semi-structured interviews with 13 timebank staff. Each timebank was visited at least twice, and all timebank activity was analysed for a period of 12 months. Data were triangulated to improve reliability. The research found that in practice, timebanks were not working as described in theory, there were small numbers of person-to-person exchanges and some timebanks had abandoned this exchange model. Timebanks faced significant implementation challenges including managing risk and safeguarding and the associated bureaucracy, a paternalistic professional culture and the complexity of the timebank mechanism which required adequate resources. Lessons for timebanks are identified, as well as transferable lessons about co-production and volunteering in social care if such schemes are to be successful in the future. 相似文献
103.
Wood RI 《Physiology & behavior》2004,83(2):279-289
Are androgens reinforcing? Androgenic-anabolic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, often with negative long-term health consequences. As a result, in 1991, testosterone was declared a controlled substance. Recently, Brower [K.J. Brower, Anabolic steroid abuse and dependence. Curr. Psychiatry Rep. 4 (2002) 377-387.] proposed a two-stage model of AAS dependence. Users initiate steroid use for their anabolic effects on muscle growth. With continued exposure, dependence on the psychoactive effects of AAS develops. However, it is difficult in humans to separate direct psychoactive effects of AAS from the user's psychological dependence on the anabolic effects of AAS. Thus, studies in laboratory animals are useful to explore androgen reinforcement. Testosterone induces a conditioned place preference in rats and mice, and is voluntarily consumed through oral, intravenous, and intracerebroventricular self-administration in hamsters. Active, gonad-intact male and female hamsters will deliver 1 microg/microl testosterone into the lateral ventricles. Indeed, some individuals self-administer testosterone intracerebroventricularly to the point of death. Male rats develop a conditioned place preference to testosterone injections into the nucleus accumbens, an effect blocked by dopamine receptor antagonists. These data suggest that androgen reinforcement is mediated by the brain. Moreover, testosterone appears to act through the mesolimbic dopamine system, a common substrate for drugs of abuse. Nonetheless, androgen reinforcement is not comparable to that of cocaine or heroin. Instead, testosterone resembles other mild reinforcers, such as caffeine, nicotine, or benzodiazepines. The potential for androgen addiction remains to be determined. 相似文献
104.
Candace S. Johnson Ming-Jei Chang Wei-Dong Yu Ruth A. Modzelewski Jennifer R. Grandis Daniel R. Vlock Philip Furmanski 《Cancer chemotherapy and pharmacology》1993,32(5):339-346
Administration of interleukin-1 (IL-1 ) plus certain cytotoxic drugs causes substantially greater clonogenic tumor-cell kill and tumor-regrowth delay than does treatment with either agent alone. IL-1 itself has little effect on tumor growth despite its ability to induce acute hemorrhagic necrosis, restrict tumor blood flow, and cause microvascular injury in a variety of murine model systems. To investigate further IL-1 's ability to enhance the antitumor activity of cytotoxic drugs, we initiated studies to examine the effect of IL-1 on cisplatin (cDDP)-mediated cytotoxicity using the RIF-1 tumor system. The antitumor activity of IL-1 and cDDP was quantitated through standard clonogenic tumor-cell survival assays, a tumor hemorrhagic necrosis assay and tumor-regrowth delay studies, with the interaction between IL-1 and cDDP being analyzed through median dose-effect. In vitro, IL-1 had no enhancing effect on the cDDP-mediated tumorcell kill. For examination of the in vivo efficacy of this regimen. RIF-1 tumor-bearing C3H/HeJ mice (14 days postimplantation) were treated concurrently with single i.p. injections of IL-1 and/or cDDP at various doses. The increased clonogenic tumor-cell kill obtained with IL-1 /cDDP was dose-dependent, with significant enhancement by IL-1 being observed (P<0.001), even at the lowest doses tested (2 mg/kg and 6 g/kg for cDDP and IL-1 , respectively), but it did not correlate with an increase in tumor hemorrhage. Using median dose-effect analysis, this interaction was determined to be strongly synergistic. When treated animals were monitored for long-term antitumor effects, combinations with IL-1 significantly increased the tumor-regrowth delay and decreased the fractional tumor volume (P<0.001). These results demonstrate that IL-1 synergistically enhances cDDP mediated in vivo antitumor activity and suggest that the combination of IL-1 and cDDP may have potential therapeutic application in the design of effective treatment modalities for cancer.Abbreviations IL-1
interleukin-1
- cDDP
cis-diamminedichloroplatinum (cisplatin)
- BRMs
biological response modifiers
- TNF
tumor necrosis factor
- IFN
interferon
- Fa
traction affected
- Dm or ED50
drug concentration necessary to produce Fa=0.5 as compared with untreated controls
- CI
combination index; SF, surviving fraction
- ANOVA
oneway analysis of variance
This work was supported in part by Public Health Service grant CA-48077 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services, by the Mary Hillman Jennings Foundation, and by the Ramona DeSantis Cancer Research Fund 相似文献
105.
Peter J. O'Dwyer Mark J. Cornfeld Ruth Peter Robert L. Comis 《Cancer chemotherapy and pharmacology》1990,27(2):131-134
Summary The ongoing evaluation of combination chemotherapy with 5-fluorouracil (5-FU) and cisplatin in several tumors prompted a phase I clinical trial of cisplatin with 5-FU modulated by leucovorin. A total of 26 patients were treated with varying doses of 5-FU by continuous i.v. infusion for 5 days; 200 mg/m2 leucovorin was given by daily bolus injection for 5 days; and 20 mg/m2 cisplatin was infused over 2 h on each day of treatment. Courses were repeated every 21–28 days. The starting dose of 5-FU was 300 mg/m2. Poor-risk patients (extensive prior radiation, performance status of 2 or worse) did not tolerate the initial dose; the maximum tolerated dose of 5-FU in this group was 200 mg/m2 daily. Good-risk patients tolerated 300 mg/m2, but a majority had excessive toxicity at higher doses. The dose-limiting toxicity was gastrointestinal (mucositis/diarrhea) and/or myelosuppression; additional side effects included were nausea and vomiting (grade 2) and ataxia (one patient). Among 13 patients with colorectal cancer, 4 partial responses were observed. The marked reduction in the tolerable dose of 5-FU occasioned by the addition of modulating doses of leucovorin is noteworthy. The response observed support further investigation of this regimen in phase II trials. 相似文献
106.
Perrin JM Kuhlthau K Walker DK Stein RE Newacheck PW Gortmaker SL 《Maternal and child health journal》1997,1(1):15-23
Objective: Children with chronic health conditions face special issues in their interactions with managed care. These children often require additional and more varied services than do other children. Managed care plans increasingly include these children, especially with the growth of Medicaid managed care. This article examines the special issues facing children with chronic conditions and develops strategies for monitoring their care in managed care settings. Methods: The project staff conducted an extensive review of the research and policy literature related to managed care and the special needs of families with children with chronic conditions. The project also reviewed current and proposed plans of federal, state, and private groups for monitoring and, working with parents and other outside groups, identified key issues to consider in developing monitoring plans. Results: The relative rarity of many childhood conditions and the complex interactions among child, family, and community over time make assessment of their care difficult. We describe these child and family characteristics, outline essential features and domains for monitoring systems, and describe population-based and plan-based monitoring systems to assess managed care for these children and their families. Conclusions: Monitoring for children with chronic conditions in managed care arrangements will require public health agencies and health providers to define populations systematically, assess across a variety of conditions, and monitor several domains central to the health of these families. 相似文献
107.
Hasmall Susan C.; Pyrah Ian T. G.; Soames Anthony R.; Roberts Ruth A. 《Toxicological sciences》1997,40(1):129-137
The involvement of the immediate-early (IE) genes c-fos, c-jun,and c-myc in regenerative liver hyperplasia is accepted, buttheir involvement in direct hyperplasia is uncertain. We haveexamined the hypothesis that the ability to induce IE genesmay reflect the hepatocarcinogenic potential of a chemical.The ability of 1,4-dichlorobenzene (DCB) (300 mg/kg) (a noncarcinogemcrat liver mitogen), diethylhexyl phthalate (DEHP) (950 mg/kg),and chlorendic acid (120 mg/kg) (both nongenotoxic hepatocarcinogens)to induce c-fos, c-jun. and c-myc expression in rat liver wasdetermined by Northern blot analysis and by in situ hybridization.Results were correlated to hepatic labeling index (LI) as determinedby incorporation of BrdU in each of three lobes for each ofthree male F344 rats per group. Carbon tetrachioride (CCl4 (2ml/kg) was used as a positive control. Increased LI was precededby elevated expression of all three IE genes after CCl4., butalso after DCB and DEHP, although induction by these was lessmarked. In all cases, there was considerable interanimal variationwithin groups, but little interlobe variation. Interestingly,there was a good correlation (r2 0.85) between c-myc expressionand LI, but not between LI and c-fos or c-jun. Despite the disparatecarcinogenic potential of DEHP and DCB, both chemicals inducedsimilar patterns of IE gene expression, suggesting that thiscannot distinguish hepatocarcinogenic liver mitogens from noncarcinogenicliver mitogens. These data assist in the evaluation of IE geneexpression both as a marker of direct versus regenerative hyperplasiaand as an indicator of the hepatocarcinogenic potential of livermitogens. 相似文献
108.
109.
110.
Ruth A. Etzel David L. Ashley 《International archives of occupational and environmental health》1994,66(2):125-129
Between March and November of 1991, approximately 9000 workers from 43 different countries battled the burning oil wells in Kuwait. To document the exposure of persons in Kuwait during the oil well fires to volatile organic compounds (VOCs), we obtained samples of blood from 14 U.S. personnel in Kuwait City in May of 1991 (group I) and 40 American firefighters working in the oil fields in October of 1991 (group II). Concentrations of VOCs in group I and group II were compared with those of a random sample of 114 persons in the United States (reference group). The median concentrations of VOCs in group I were equal to or lower than those in the reference group. We found significant differences between the median concentrations of several VOCs in group 11 and the reference group. Median levels of ethylbenzene were about 10 times higher among group II than among the reference group (0.53 g/I vs 0.052 g/l). Median levels of benzene, m-/p-xylene, o-xylene, styrene, and toluene among group II were more than double those of the reference group. Although firefighters had higher median concentrations of VOCs than the reference group, those American personnel in Kuwait not involved in fighting the oil fires had concentrations of VOCs comparable to those in the reference group. Blood VOC measurements indicate a significant increase in exposure to VOCs in firefighters, but do not demonstrate this in personnel in Kuwait City. 相似文献