Publications by authors named "Charles Katholi"

Despite mounting evidence that social factors and public policies affect state infant mortality rates (IMRs), few researchers have examined variation in IMRs associated with those factors and policies. We quantified disparities in infant mortality by state social factors and public policy characteristics. We hypothesized that some social factors and public policies would be more strongly associated with infant mortality than others, and that states with similar factors and policies would form clusters with varying levels of infant mortality.

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Objectives: The American Academy of Pediatrics (AAP) calls for the inclusion of office-based pediatricians in disaster preparedness and response efforts. However, there is little research about disaster preparedness and response on the part of pediatric practices. This study describes the readiness of pediatric practices to respond to disaster and delineates factors associated with increased preparedness.

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In the estimation of proportions by group testing, unequal sized groups results in an ambiguous ordering of the sample space, which complicates the construction of exact confidence intervals. The total number of positive groups is shown to be a suitable statistic for ordering outcomes, provided its ties are broken by the MLE. We propose an interval estimation method based on this quantity, with a mid-P correction.

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Background: Onchocerciasis a neglected tropical disease that historically has been a major cause of morbidity and an obstacle to economic development in the developing world. It is caused by infection with Onchocerca volvulus, which is transmitted by black flies of the genus Simulium. The discovery of the potent effect of Mectizan (ivermectin) on O.

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Onchocerciasis is a neglected tropical disease that has plagued mankind for decades with pathologies that involve the eyes and the skin. The WHO and the global health community have earmarked the disease for global elimination by 2045. However, as control programmes shift focus from reduction of the burden of the disease to elimination, new tools and strategies may be needed to meet targets.

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Entomological measures of transmission are important metrics specified by the World Health Organization to document the suppression and interruption of transmission of , the causative agent of onchocerciasis. These metrics require testing of large numbers of vector black flies. Black fly collection has relied on human landing collections, which are inefficient and potentially hazardous.

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A critique of the recommendation that skin snips be used for post-MDA surveillance of formerly endemic onchocerciasis areas is provided. After considering several fundamental aspects of the use of this methodology within the context of prolonged mass distribution of ivermectin, we argue that skin-snipping has no value for monitoring onchocerciasis elimination programs.

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The suite of pheromones that promote communal oviposition by Simulium vittatum, a North American black fly species, was identified and characterized using gas chromatography-mass spectrometry, electrophysiological, and behavioral bioassays. Behavioral assays demonstrated that communal oviposition was induced by egg-derived compounds that were active at short range and whose effect was enhanced through direct contact. Three compounds (cis-9-tetradecen-1-ol, 1-pentadecene, and 1-tridecene) were identified in a non-polar solvent extract of freshly deposited S.

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Background: Entomological indicators are considered key metrics to document the interruption of transmission of Onchocerca volvulus, the etiological agent of human onchocerciasis. Human landing collection is the standard employed for collection of the vectors for this parasite. Recent studies reported the development of traps that have the potential for replacing humans for surveillance of O.

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We present a frequentist Bernoulli-Beta hierarchical model to relax the constant prevalence assumption underlying the traditional prevalence estimation approach based on pooled data. This assumption is called into question when sampling from a large geographic area. Pool screening is a method that combines individual items into pools.

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Uganda is the only African country whose onchocerciasis elimination program uses a two-pronged approach of vector control and mass drug distribution. The Ugandan program relies heavily upon the use of serosurveys of children to monitor progress toward elimination. The program has tested over 39,000 individuals from 11 foci for Onchocerca volvulus exposure, using the Ov16 ELISA test.

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Background: Human landing collections are currently the standard method for collecting onchocerciasis vectors in Africa and Latin America. As part of the efforts to develop a trap to replace human landing collections for the monitoring and surveillance of onchocerciasis transmission, comprehensive evaluations of several trap types were conducted to assess their ability to collect Simulium ochraceum sensu lato, one of the principal vectors of Onchocerca volvulus in Latin America.

Methodology/principal Findings: Diverse trap designs with numerous modifications and bait variations were evaluated for their abilities to collect S.

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Objective: State public health preparedness units (SPHPUs) were developed in response to federal funding to improve response to disasters: a responsibility that had not traditionally been within the purview of public health. The SPHPUs were created within the existing public health organizational structure, and their placement may have implications for how the unit functions, how communication takes place, and ultimately how well the key responsibilities are performed. This study empirically identifies a taxonomy of similarly structured SPHPUs and examines whether this structure is associated with state geographic, demographic, and threat-vulnerability characteristics.

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The control of bovine tuberculosis and atypical mycobacterioses in cattle in developing countries is important but difficult because of the existence of wildlife reservoirs. In cattle farms in Tanzania, mycobacteria were detected in 7.3% of 645 small mammals and in cow's milk.

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Study Objective: To study the effect of intravenous (IV) sedation on blood pressure (BP), heart rate (HR), and respiratory rates (RR) to determine if IV sedatives differ with respect to their effect on BP, HR, and RR.

Design: Prospective, randomized, single-blinded, placebo-controlled study.

Setting: Monitored patient care room at a clinical research center.

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Host blood meals in seven mosquito species previously shown to be infected with eastern equine encephalitis virus at a site in the Tuskegee National Forest in southcentral Alabama were investigated. Of 1374 blood meals derived from 88 different host species collected over 6 years from these seven mosquito species, 1099 were derived from Culex erraticus. Analysis of the temporal pattern of Cx.

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Two promoters from the human filarial parasite Brugia malayi have been mapped in detail. The essential domains of both promoters lacked canonical eukaryotic core promoter motifs. However, the largest contiguous essential domain in both promoters flanked and included the splice leader addition site.

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Reptiles and amphibians constitute a significant portion of vertebrate biomass in terrestrial ecosystems and may be important arbovirus reservoirs. To investigate mosquito preference for ectothermic hosts, feeding indices were calculated from data collected in Tuskegee National Forest, Alabama, USA. Four mosquito species fed upon ectothermic hosts, with Culex peccator and Cx.

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Marked spatiotemporal variabilities in mosquito infection of arboviruses, exemplified by the transmission of West Nile virus (WNV) in America, require adaptive strategies for mosquito sampling, pool screening and data analyses. Currently there is a lack of reliable and consistent measures of risk exposure, which may compromise comparison of surveillance data. Based on quantitative reasoning, we critically examined fundamental issues regarding mosquito sampling design and estimation of transmission intensity.

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Background: The use of safe iodinated contrast media (CM) to prevent contrast-induced nephropathy (CIN) is an important consideration among renally impaired diabetic patients during coronary angiography.

Hypothesis: Diabetic patients with normal or mild renal dysfunction are less likely to receive renal protective measures during angiography, yet they may also be at risk for CIN. We compared the renal effects of iopamidol and iodixanol in diabetic patients who were referred for angiography.

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Unravelling gene regulatory mechanisms in human filarial parasites will require an understanding of their basic promoter structure. Only a single promoter from a human filarial parasite has been characterised in detail, the 70 kDa heat shock promoter of Brugia malayi (BmHSP70). This promoter was found to lack features found in a typical eukaryotic promoter.

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With the rising number of patients with human immunodeficiency virus (HIV)/AIDS in developing countries, the control of mycobacteria is of growing importance. Previous studies have shown that rodents and insectivores are carriers of mycobacteria. However, it is not clear how widespread mycobacteria are in these animals and what their role is in spreading them.

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The source of bloodmeals in 2,082 blood-fed mosquitoes collected from February 2002 through December 2003 in Memphis and surrounding areas of Shelby County, Tennessee were determined. Members of the genus Culex and Anopheles quadrimaculatus predominated in the collections. Members of the Cx.

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An experimental study of lateral displacement of ganglion cells (GCs) from foveal cones in six human retinas is reported. At 406-675 microm in length, as measured in radially oriented cross-sections, Henle fibers are substantially longer than previously reported. However, a new theoretical model indicates that the discrepancies in these reports are mainly due to meridional differences.

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To study the impact of mass Mectizan treatment on Onchocerca volvulus transmission in Mexico, entomological surveys were carried out in the endemic foci of Oaxaca, Southern Chiapas, and Northern Chiapas. Collected flies were screened by polymerase chain reaction (PCR) for O. volvulus parasites.

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