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91.
María R Becerra José A Tantaleán Víctor J Suárez Margarita C Alvarado Jorge L Candela Flor C Urcia 《BMC pediatrics》2010,10(1):1-9
Background
Infantile spasms represent a serious epileptic syndrome that occurs in the early infantile age. ACTH and Vigabatrin are actively investigated drugs in its treatment. This study describes the comparison of their efficacy in a large series of patients with infantile spasms from Pakistan.Methods
All patients with infantile spasms who presented to Aga Khan University Hospital, Karachi, Pakistan from January, 2006 to April, 2008 were included in this study. Inclusion criteria were clinical symptoms of infantile spasms, hypsarrythmia or modified hyparrythmia on electroencephalography, at least six months of follow-up period and receipt of any of the two drugs mentioned above. The type of drug distribution was random according to the availability, cost and ease of administration.Results
Fifty six cases fulfilled the inclusion criteria. 62.5% were males. Mean age at onset of seizures was 5 ± 1.4 months. Fifty two (92.8%) patients demonstrated hypsarrythmia on electroencephalography. 64.3% cases were identified as symptomatic while 19.6% were cryptogenic and 16.1% were idiopathic. Eighteen patients received ACTH while 38 patients received Vigabatrin as first line therapy. Initial response to first line therapy was similar (50% for ACTH and 55.3% for Vigabatrin). Overall, the symptomatic and idiopathic groups responded better to Vigabatrin. The relapse rate was higher for ACTH as compared to Vigabatrin (55.5% vs. 33.3%) when considering the first line therapy. Four patients evolved to Lennox-Gastaut variant; all of these patients had initially received Vigabatrin and then ACTH.Conclusion
Vigabatrin and ACTH showed no significant difference in the initial treatment of infantile spasms. However, patients receiving ACTH were 1.2 times more likely to relapse as compared to the patients receiving Vigabatrin when considering monotherapy. We suggest that Vigabatrin should be the initial drug of choice in patients presenting with infantile spasms. However, larger studies from developing countries are required to validate the therapeutic trends observed in this study. 相似文献92.
Maria-Victoria Zunzunegui Beatriz-Eugenia Alvarado François Béland Bilkis Vissandjee 《Social science & medicine (1982)》2009
This paper describes differences in health and functional status among older men and women and attempts to anchor the explanations for these differences within a lifecourse perspective. Seven health outcomes for men and women 60 years and older from seven Latin American and Caribbean cities are examined, using data from the 2000 SABE survey (Salud, Bienestar y Envejecimiento—n = 10,587). Age-adjusted as well as city- and sex-specific prevalence was estimated for poor self-rated health, comorbidity, mobility limitations, cognitive impairment, depressive symptoms and disability in basic and instrumental activities of daily living. Logistic regressions were fitted to determine if the differences between men and women in each outcome could be explained by differential exposures in childhood (hunger, poverty), adulthood (education, occupation) and old age (income) and/or by differential vulnerability of men and women to these exposures. Sao Paulo, Santiago and Mexico, cities in countries with a high level of income inequalities, presented the highest prevalence of disability, functional limitations and poor physical health for both women and men. Women showed poorer health outcomes as compared with men for all health indicators and in all cities. Controlling for lifecourse exposures in childhood, adulthood and old age did not attenuate these differences. Women's unadjusted and adjusted odds of reporting poor self-rated health, cognitive impairment and basic activities of daily living disability were approximately 50% higher than for men, twice as high for number of comorbidities, depressive symptoms and instrumental activities of daily living disability, and almost three times as high for mobility limitations. Higher vulnerability to lifecourse exposures in women as compared with men was not found, meaning that lifecourse exposures have similar odds of poor health outcomes for men and women. A more integrated understanding of how sex and gender act together to influence health and function in old age needs consideration of additional biological and social factors. 相似文献
93.
Verónica Jiménez-Suárez Antonio Nieto-Camacho Manuel Jiménez-Estrada Brenda Alvarado Sánchez 《Pharmaceutical biology》2016,54(9):1822-1830
Context Hamelia patens Jacq. (Rubiaceae) is traditionally used to treat wounds, inflammation and diabetes. However, there is still a lack of scientific evidence to support these applications.Objective The objective of this study is to evaluate the anti-inflammatory, antioxidant and antidiabetic activities of Hamelia patens, and identify its bioactive compounds.Materials and methods Four extracts were obtained by maceration and liquid–liquid extraction: HEX, DCM–EtOAc, MeOH–EtOAc and MeOH–Aq. The anti-inflammatory effect was evaluated orally on rat paw carrageenan-induced oedema over 6?h (50, 200 and 500?mg/kg), and topically in mouse ear oedema induced by 12-tetradecanoylphorbol-13-acetate (TPA) after 4?h (0.5 and 1?mg/ear). We also evaluated myeloperoxidase levels in ear tissue, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and in vitro α-glucosidase inhibition. The chemical compounds were separated by column chromatography and identified by spectroscopic analysis.Results We found that the oral administration of the HEX extract at 500 and 200?mg/kg significantly decreased the carrageenan-induced inflammation after 1 and 3?h, respectively. The MeOH–EtOAc extract significantly inhibited myeloperoxidase activity (83.5%), followed by the DCM–EtOAc extract (76%), β-sitosterol/stigmasterol (72.7%) and the HEX extract (55%), which significantly decreased oedema induced by TPA at both doses, giving a similar effect to indomethacin. We also found that the MeOH–EtOAc, MeOH–Aq and DCM–EtOAc extracts showed good DPPH scavenging activity (IC50 values of 18.6, 93.9 and 158.2?μg/mL, respectively). The HEX extract showed the lowest α-glucosidase inhibition (an IC50 value of 26.07?μg/mL), followed by the MeOH–EtOAc extract (an IC50 value of 30.18?μg/mL), β-sitosterol/stigmasterol (IC50 34.6?μg/mL) and compound A ((6E,10E,14E,18E)-2,6,10,14,18,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, an IC50 value of 114.6?μg/mL), which were isolated for the first time from Hamelia patens.Discussion and conclusion Hamelia patens possesses anti-inflammatory, antioxidant and α-glucosidase inhibitory activities, which support its traditional use. These effects can be attributed to the identified compounds. 相似文献
94.
Alvarado Esquivel C Leroux-Roels G 《Revista de investigación clínica; organo del Hospital de Enfermedades de la Nutrición》1999,51(5):315-322
This review summarizes what is currently known about the cellular and humoral immune responses to hepatitis C virus. The results of viral protein immunogenicity studies reported so far are analyzed, and points of controversy about the immunology and immunopathology of hepatitis C are discussed. A body of evidence supports the existence in hepatitis C virus-infected subjects of strong humoral and cellular immune responses. HCV Core, NS3 and NS4 proteins are the most immunogenic antigens for B cells and HLA class II-restricted CD4+ T cells. For its part, liver-infiltrating CD8+ CTL recognize epitopes within the Core, E1, E2/NS1 and NS2 proteins in a HLA class I restricted manner. CTL responses to HCV Core, NS3, NS4 and NS5 have been detected in peripheral blood of patients chronically infected with HCV. Although these B and T cell responses may contribute to clear the virus, in most cases they are unable to resolve chronic HCV infections. No protective B or T cell epitope has been found yet. It is becoming clearer that the immune response plays a fundamental role in the pathogenesis of liver disease in hepatitis C patients. 相似文献
95.
Identifying condom users at risk for breakage and slippage: findings from three international sites. 总被引:3,自引:0,他引:3 下载免费PDF全文
A Spruyt M J Steiner C Joanis L H Glover C Piedrahita G Alvarado R Ramos C Maglaya M Cordero 《American journal of public health》1998,88(2):239-244
OBJECTIVES: This study examined whether past condom failure (breakage, slippage, or both) can predict future failure and evaluated other predictors of condom failure. METHODS: At each of 3 international sites, approximately 130 male condom users were enrolled and given 5 condoms to use for vaginal intercourse over a 3-week period. RESULTS: Men at increased risk (history of 1 or more condoms that broke or slipped off) reported approximately twice as many condom failures as those not in this group. Condom failure increased with the number of adverse condom use behaviors reported per participant. Opening condom packages with sharp objects and unrolling condoms before donning were associated with breakage. Unrolling condoms before donning and lengthy or intense intercourse were associated with slippage. Of background characteristics evaluated, having less education was associated with condom failure. CONCLUSIONS: These data suggest that a history of condom failure predicts future failure, a finding that may be useful for targeted intervention. Moreover, these data provide further evidence that certain behaviors and lower educational attainment are associated with condom failure. 相似文献
96.
Díaz S Hardy E Alvarado G Ezcurra E 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2003,19(6):1729-1737
A multi-center study was performed in Brazil, Chile, and Mexico to identify factors that may facilitate or hinder the introduction of emergency contraception (EC) as well as perceptions concerning emergency contraceptive pills. Background information on the socio-cultural, political, and legal context and the characteristics of reproductive health services was collected. The opinions of potential users and providers were obtained through discussion groups, and those of authorities and policymakers through semi-structured interviews. Barriers to introduction included: perception of EC as an abortifacient, opposition by the Catholic Church, limited recognition of sexual and reproductive rights, limited sex education, and insensitivity to gender issues. Facilitating factors were: perception of EC as a method that would prevent abortion and pregnancy among adolescents and rape victims; interest in the method shown by potential users as well as by some providers and authorities. It appears possible to reduce barriers through support from segments of society committed to improving sexual and reproductive health and adequate training of health care providers. 相似文献
97.
J. Mauricio Peñarrieta Trinidad Salluca Leslie Tejeda J. Antonio Alvarado Björn Bergenståhl 《Journal of food composition and analysis》2011,24(4-5):580-587
Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and the amounts of individual phenolic compounds were assessed in Bolivian potato cultivars (various Solanum species) before, during and after the traditional freezing and sun-drying of potatoes known as chuños. The TAC of chuños ranged from 0.4 to 2.7 μmol Trolox equivalents/g dry matter using 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and from 0.7 to 3.0 according to the ferric reduction antioxidant power (FRAP). The values of TAC obtained using FRAP were about 70% lower after freeze-drying while they remained essentially constant when measured using ABTS. High-performance liquid chromatography showed the presence of epicatechin, chlorogenic acid, gallic acid, syringaldehyde and protocatechuic acid in both potato and chuño samples although the values were lower in the chuño samples. The results suggest that the antioxidant capacity and the content of individual phenolics are somewhat decreased but far from eliminated during the process. Chuño can therefore still be considered an important source of antioxidants in the diet. 相似文献
98.
BackgroundCo-occurring disabilities are common and data indicate that those with both physical and mental disabilities face greater discrimination in the workforce. However, studies that consider disability type in determining labor market outcomes are needed; particularly in Canada.ObjectiveThe objective was to examine the association of disability type and unemployment among working-aged Canadians using data from the 2006 Participation and Activity Limitation Survey (PALS).MethodsThe 2006 PALS is a post-censal sample survey of individuals whose everyday activities are limited due to a physical/mental condition. The study design is cross-sectional. Two groups were compared: persons with one or more physical disabilities exclusively vs. those with one or more physical disabilities and a mental disability. We calculated the prevalence of unemployment and used multiple logistic regression to measure the association between disability type and unemployment, while considering relevant covariates.ResultsThe prevalence of unemployment was 20% overall; 35.4% in those with a co-morbid mental disability and 18.5% in those with exclusively physical disabilities. Those with a mental co-morbidity had approximately double the odds of being unemployed relative to those with exclusively physical disabilities and the effect remained significant (at p < 0.05) after adjustment for socio-economic indicators and disability severity.ConclusionsCompared to those with exclusively physical disabilities, individuals with co-morbid physical and mental disabilities were found to be at a significantly greater disadvantage when accessing employment. More research is needed to clarify whether these findings are indicative of discrimination and to proceed toward removing workplace barriers that persist in this population. 相似文献
99.
Because of the substantial impact of families on the developmental trajectories of children, family interventions should be a critical ingredient in comprehensive prevention programs. Very few family interventions have been adapted to be culturally sensitive for different ethnic groups. This paper examines the research literature on whether culturally adapting family interventions improves retention and outcome effectiveness. Because of limited research on the topic, the prevention research field is divided on the issue. Factors to consider for cultural adaptations of family-focused prevention are presented. Five research studies testing the effectiveness of the generic version of the Strengthening Families Program (SFP) compared to culturally-adapted versions for African Americans, Hispanic, Asian/Pacific Islander, and American Indian families suggest that cultural adaptations made by practitioners that reduce dosage or eliminate critical core content can increase retention by up to 40%, but reduce positive outcomes. Recommendations include the need for additional research on culturally-sensitive family interventions. 相似文献
100.
Analysis of small sample size studies using nonparametric bootstrap test with pooled resampling method 总被引:1,自引:0,他引:1
Alok Kumar Dwivedi Indika Mallawaarachchi Luis A. Alvarado 《Statistics in medicine》2017,36(14):2187-2205
Experimental studies in biomedical research frequently pose analytical problems related to small sample size. In such studies, there are conflicting findings regarding the choice of parametric and nonparametric analysis, especially with non‐normal data. In such instances, some methodologists questioned the validity of parametric tests and suggested nonparametric tests. In contrast, other methodologists found nonparametric tests to be too conservative and less powerful and thus preferred using parametric tests. Some researchers have recommended using a bootstrap test; however, this method also has small sample size limitation. We used a pooled method in nonparametric bootstrap test that may overcome the problem related with small samples in hypothesis testing. The present study compared nonparametric bootstrap test with pooled resampling method corresponding to parametric, nonparametric, and permutation tests through extensive simulations under various conditions and using real data examples. The nonparametric pooled bootstrap t‐test provided equal or greater power for comparing two means as compared with unpaired t‐test, Welch t‐test, Wilcoxon rank sum test, and permutation test while maintaining type I error probability for any conditions except for Cauchy and extreme variable lognormal distributions. In such cases, we suggest using an exact Wilcoxon rank sum test. Nonparametric bootstrap paired t‐test also provided better performance than other alternatives. Nonparametric bootstrap test provided benefit over exact Kruskal–Wallis test. We suggest using nonparametric bootstrap test with pooled resampling method for comparing paired or unpaired means and for validating the one way analysis of variance test results for non‐normal data in small sample size studies. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献