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111.
Dinesh DS Das ML Picado A Roy L Rijal S Singh SP Das P Boelaert M Coosemans M 《PLoS neglected tropical diseases》2010,4(10):e859
Objectives
To investigate the DDT and deltamethrin susceptibility of Phlebotomus argentipes, the vector of Leishmania donovani, responsible for visceral leishmaniasis (VL), in two countries (India and Nepal) with different histories of insecticide exposure.Methods
Standard WHO testing procedures were applied using 4% DDT and 0.05% deltamethrin impregnated papers. The effect of the physiological status (fed and unfed) of females on the outcome of the bioassays was assessed and the optimal time of exposure for deltamethrin was evaluated on a colony population. Field populations from both countries were tested.Results
Fed and unfed females responded in a similar way. For exposure time on field samples 60 min was adopted for both DDT and deltamethrin. In Bihar, knockdown and mortality with DDT was respectively 20 and 43%. In Nepal almost all sand flies were killed, except at the border with Bihar (mortality 62%). With 0.05% deltamethrin, between 96 and 100% of the sand flies were killed in both regions.Conclusions
Based on literature and present data 4% DDT and 0.05% deltamethrin seem to be acceptable discriminating concentrations to separate resistant from susceptible populations. Resistance to DDT was confirmed in Bihar and in a border village of Nepal, but the sand flies were still susceptible in villages more inside Nepal where only synthetic pyrethroids are used for indoor spraying. The low effectiveness of indoor spraying with DDT in Bihar to control VL can be partially explained by this resistance hence other classes of insecticides should be tested. In both countries P. argentipes sand flies were susceptible to deltamethrin. 相似文献112.
Background
While three countries in South Asia decided to eliminate anthroponotic visceral leishmaniasis (VL) by 2015, its control in other regions seems fraught with difficulties. Is there a scope for more effective VL control in the Americas where transmission is zoonotic? We reviewed the evidence on VL control strategies in Latin America—diagnosis, treatment, veterinary interventions, vector control—with respect to entomological and clinical outcomes.Methodology/Principal Findings
We searched the electronic databases of MEDLINE, LILACS, and the Cochrane Central Register of Controlled Trials, from 1960 to November 2008 and references of selected articles. Intervention trials as well as observational studies that evaluated control strategies of VL in the Americas were included. While the use of rapid diagnostic tests for VL diagnosis seems well established, there is a striking lack of evidence from clinical trials for drug therapy and few well designed intervention studies for control of vectors or canine reservoirs.Conclusion
Elimination of zoonotic VL in the Americas does not seem a realistic goal at this point given the lack of political commitment, gaps in scientific knowledge, and the weakness of case management and surveillance systems. Research priorities and current strategies should be reviewed with the aim of achieving better VL control. 相似文献113.
114.
115.
Differences in risk factors for second and third degree hypospadias in the national birth defects prevention study 下载免费PDF全文
116.
Edwin C. M. Mariman F. G. Bouwman Erik E. J. G. Aller Marleen A. van Baak Ping Wang 《Genes & nutrition》2014,9(3)
Relatively rare variants with a moderate-to-high biological effect may contribute to the genetic predisposition of common disorders. To investigate this for obesity, we performed exome sequencing for 30 young (mean age: 29.7 years) extremely obese Caucasian subjects (mean body mass index: 51.1 kg/m2; m/f = 11/29). Rare variants with a moderate-to-high predicted biological effect were assembled and subjected to functional clustering analysis. It showed that the 55 clustered protocadherin genes on chromosome 5q31 have a significantly (P = 0.002) higher frequency of rare variants than a set of 325 reference genes. Since the protocadherin genes are expressed in the hypothalamus, we tested another 167 genes related to the function of the hypothalamus, but in those genes, the frequency of rare variants was not different from that of the reference genes. To verify the relation of variation in the protocadherin genes with extreme obesity, we analyzed data from more than 4,000 European Americans present on the Exome Variant Server, representing a sample of the general population. The significant enrichment of rare variants in the protocadherin genes was only observed with the group of extremely obese individuals but not in the “general population”, indicating an association between rare variants in the protocadherin cluster genes and extreme obesity. 相似文献
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118.
Objective
To assess the coverage for cervical cancer screening as well as the use of cervical cytology, colposcopy and other diagnostic and therapeutic interventions on the uterine cervix in Belgium, using individual health insurance data.Methods
The Intermutualistic Agency compiled a database containing 14 million records from reimbursement claims for Pap smears, colposcopies, cervical biopsies and surgery, performed between 2002 and 2006. Cervical cancer screening coverage was defined as the proportion of women aged 25–64 that had a Pap smear within the last 3 years.Results
Cervical cancer screening coverage was 61% at national level, for the target population of women between 25 and 64 years old, in the period 2004–2006. Differences between the 3 regions were small, but varied more substantially between provinces. Coverage was 70% for 25–34 year old women, 67% for those aged 35–39 years, and decreased to 44% in the age group of 60–64 years. The median screening interval was 13 months. The screening coverage varied substantially by social category: 40% and 64%, in women categorised as beneficiary or not-beneficiary of increased reimbursement from social insurance, respectively. In the 3-year period 2004–2006, 3.2 million screen tests were done in the target group consisting of 2.8 million women. However, only 1.7 million women got one or more smears and 1.1 million women had no smears, corresponding to an average of 1.88 smears per woman in three years of time. Colposcopy was excessively used (number of Pap smears over colposcopies = 3.2). The proportion of women with a history of conisation or hysterectomy, before the age of 65, was 7% and 19%, respectively.Conclusion
The screening coverage increased slightly from 59% in 2000 to 61% in 2006. The screening intensity remained at a high level, and the number of cytological examinations was theoretically sufficient to cover more than the whole target population. 相似文献119.
Background
Intimate partner violence (IPV) around the time of pregnancy is a widespread global health problem with many negative consequences. Nevertheless, a lot remains unclear about which interventions are effective and might be adopted in the perinatal care context.Objective
The objective is to provide a clear overview of the existing evidence on effectiveness of interventions for IPV around the time of pregnancy.Methods
Following databases PubMed, Web of Science, CINAHL and the Cochrane Library were systematically searched and expanded by hand search. The search was limited to English peer-reviewed randomized controlled trials published from 2000 to 2013. This review includes all types of interventions aiming to reduce IPV around the time of pregnancy as a primary outcome, and as secondary outcomes to enhance physical and/or mental health, quality of life, safety behavior, help seeking behavior, and/or social support.Results
We found few randomized controlled trials evaluating interventions for IPV around the time of pregnancy. Moreover, the nine studies identified did not produce strong evidence that certain interventions are effective. Nonetheless, home visitation programs and some multifaceted counseling interventions did produce promising results. Five studies reported a statistically significant decrease in physical, sexual and/or psychological partner violence (odds ratios from 0.47 to 0.92). Limited evidence was found for improved mental health, less postnatal depression, improved quality of life, fewer subsequent miscarriages, and less low birth weight/prematurity. None of the studies reported any evidence of a negative or harmful effect of the interventions.Conclusions and implications
Strong evidence of effective interventions for IPV during the perinatal period is lacking, but some interventions show promising results. Additional large-scale, high-quality research is essential to provide further evidence about the effect of certain interventions and clarify which interventions should be adopted in the perinatal care context. 相似文献120.
Rafael Delgado y Palacios Marleen Verhoye Kim Henningsen Ove Wiborg Annemie Van der Linden 《PloS one》2014,9(4)
The pathophysiology of major depressive disorder (MDD) and other stress related disorders has been associated with aberrations in the hippocampus and the frontal brain areas. More recently, other brain regions, such as the caudate nucleus, the putamen and the amygdala have also been suggested to play a role in the development of mood disorders. By exposing rats to a variety of stressors over a period of eight weeks, different phenotypes, i.e. stress susceptible (anhedonic-like) and stress resilient animals, can be discriminated based on the sucrose consumption test. The anhedonic-like animals are a well validated model for MDD. Previously, we reported that in vivo diffusion kurtosis imaging (DKI) of the hippocampus shows altered diffusion properties in chronically stressed rats independent of the hedonic state and that the shape of the right hippocampus is differing among the three groups, including unchallenged controls. In this study we evaluated diffusion properties in the prefrontal cortex, caudate putamen (CPu) and amygdala of anhedonic-like and resilient phenotypes and found that mean kurtosis in the CPu was significantly different between the anhedonic-like and resilient animals. In addition, axial diffusion and radial diffusion were increased in the stressed animal groups in the CPu and the amygdala, respectively. Furthermore, we found that the CPu/brain volume ratio was increased significantly in anhedonic-like animals as compared with control animals. Concurrently, our results indicate that the effects of chronic stress on the brain are not lateralized in these regions. These findings confirm the involvement of the CPu and the amygdala in stress related disorders and MDD. Additionally, we also show that DKI is a potentially important tool to promote the objective assessment of psychiatric disorders. 相似文献