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51.
BackgroundUrinary Schistosomiasis is a neglected tropical disease endemic in many sub Saharan -African countries. Collectin Kidney 1 (CL-K1, encoded by COLEC11 on chromosome 2p25.3), a member of the vertebrate C-type lectin super family, has recently been identified as pattern-recognition molecule (PRR) of the lectin complement pathway. CL-K1 is preferentially expressed in the kidneys, but also in other organs and it is considered to play a role in host defense to some infectious agents. Schistosome teguments are fucosylated and CL-K1 has, through its collagen-like domain, a high binding affinity to fucose.ConclusionsIn agreement with findings from our earlier published study, our findings support the observation that CL-K1 and their functional variants may be host factors associated with protection in schistosomiasis and may be a useful marker for further investigations.  相似文献   
52.

Background

Malaria and intestinal helminths co-infection are major public health problems particularly among school age children in Nigeria. However the magnitude and possible interactions of these infections remain poorly understood. This study determined the prevalence, impact and possible interaction of Plasmodium falciparum and intestinal helminths co-infection among school children in rural communities of Kwara State, Nigeria.

Methods

Blood, urine and stool samples were collected from 1017 primary school pupils of ages 4–15 years. Stool samples were processed using both Kato-Katz and formol-ether concentration techniques and microscopically examined for intestinal helminths infection. Urine samples were analyzed using sedimentation method for Schistosoma haematobium. Plasmodium falciparum was confirmed by microscopy using thick and thin blood films methods and packed cell volume (PCV) was determined using hematocrit reader. Univariate analysis and chi-square statistical tests were used to analyze the data.

Results

Overall, 61.2% of all school children had at least an infection of either P. falciparum, S. haematobium, or intestinal helminth. S. haematobium accounted for the largest proportion (44.4%) of a single infection followed by P. falciparum (20.6%). The prevalence of malaria and helminth co-infection in the study was 14.4%. Four species of intestinal helminths were recovered from the stool samples and these were hookworm (22.5%), Hymenolepis species (9.8%), Schistosoma mansoni (2.9%) and Enterobius vermicularis (0.6%). The mean densities of P. falciparum in children co-infected with S. haematobium and hookworm were higher compared to those infected with P. falciparum only though not statistically significant (p = 0.062). The age distribution of both S. haematobium (p = 0.049) and hookworm (p = 0.034) infected children were statistically significant with the older age group (10–15 years) recording the highest prevalence of 47.2% and 25% respectively. Children who were infected with S. haematobium (RR = 1.3) and hookworm (RR = 1.4) have equal chances of being infected with P. falciparum as children with no worm infection. On the other hand children infected with Hymenolepis spp. (p<0.0001) are more likely to be infected with P. falciparum than Hymenolepis spp. uninfected children (RR = 2.0)

Conclusions

These findings suggest that multiple parasitic infections are common in school age children in rural communities of Kwara State Nigeria. The Hymenolepis spp. induced increase susceptibility to P. falciparum could have important consequences on how concurrent infections affect the expression or pathogenesis of these infections.  相似文献   
53.

Background

In Nigeria, 30% of child deaths are due to malaria. The National Malaria Control Program of Nigeria (NMCP) during 2009 initiated a program to improve the quality of paediatric malaria services delivered in health facilities (HF). This study reports a rapid approach used to assess the existing quality of services in Jigawa state at decentralised levels of the health system.

Methods

NMCP selected Lot Quality Assurance Sampling (LQAS) to identify the variation in HF service quality among Senatorial Districts (SD). LQAS was selected because it was affordable and could be used by local health workers (HW) in a population-based survey. NMCP applied a 2-stage LQAS using a structured Rapid Health Facility Assessment (R-HFA) tool to identify high and low performing SD for specified indicators.

Findings

LQAS identified variations in HF performance (n = 21) and enabled resources to be targeted to address priorities. All SD exhibited deficient essential services, supplies and equipment. Only 9.7% of HF had Artemisinin-based Combination Therapies and other first-line treatments for childhood illnesses. No SD and few HF exhibited adequate HW performance for the assessment, treatment or counselling of sick children. Using the IMCI algorithm, 17.5% of HW assessed the child’s vaccination status, 46.8% assessed nutritional status, and 65.1% assessed children for dehydration. Only 5.1% of HW treatments were appropriate for the assessment. Exit interviews revealed that 5.1% of caregivers knew their children’s illness, and only 19.9% could accurately describe how to administer the prescribed drug.

Conclusion

This R-HFA, using LQAS principles, is a rapid, simple tool for assessing malaria services and can be used at scale. It identified technical deficiencies that could be corrected by improved continuing medical education, targeted supervision, and recurrent R-HFA assessments of the quality of services.  相似文献   
54.
55.
Field surveys were conducted during the 2012 wet season in five Local Government Areas (LGAs) each of Kaduna and Kano States, Nigeria, to determine the incidence of potyviruses infecting sorghum. Sorghum leaves (n = 450) showing mosaic, streak, dwarfism and asymptomatic ones were collected from 30 fields. Based on the fields, the virus disease incidence in Kaduna State was 19.3, 17.1, 53.7, 35.4 and 32.7% for Sabon Gari, Giwa, Lere, Kubau and Makarfi LGAs, respectively. In Kano State, the incidence was 13.3, 32.9, 28.9, 34.3 and 50.9% for Tsanyawa, Minjibir, Wudil, Sumaila and Garun Malam LGAs, respectively. Enzyme-linked immunosorbent assay (ELISA) was employed in the detection of the viruses. There was overall incidence of Sorghum mosaic virus 2.8%, Maize dwarf mosaic virus 2.0%, Sugarcane mosaic virus 3.3% and unidentified potyvirus 4.2% from the two states.  相似文献   
56.

Background

Rapid muscle fatigue during functional electrical stimulation (FES)-evoked muscle contractions in individuals with spinal cord injury (SCI) is a significant limitation to attaining health benefits of FES-exercise. Delaying the onset of muscle fatigue is often cited as an important goal linked to FES clinical efficacy. Although the basic concept of fatigue-resistance has a long history, recent advances in biomedical engineering, physiotherapy and clinical exercise science have achieved improved clinical benefits, especially for reducing muscle fatigue during FES-exercise. This review evaluated the methodological quality of strategies underlying muscle fatigue-resistance that have been used to optimize FES therapeutic approaches. The review also sought to synthesize the effectiveness of these strategies for persons with SCI in order to establish their functional impacts and clinical relevance.

Methods

Published scientific literature pertaining to the reduction of FES-induced muscle fatigue was identified through searches of the following databases: Science Direct, Medline, IEEE Xplore, SpringerLink, PubMed and Nature, from the earliest returned record until June 2015. Titles and abstracts were screened to obtain 35 studies that met the inclusion criteria for this systematic review.

Results

Following the evaluation of methodological quality (mean (SD), 50 (6) %) of the reviewed studies using the Downs and Black scale, the largest treatment effects reported to reduce muscle fatigue mainly investigated isometric contractions of limited functional and clinical relevance (n = 28). Some investigations (n = 13) lacked randomisation, while others were characterised by small sample sizes with low statistical power. Nevertheless, the clinical significance of emerging trends to improve fatigue-resistance during FES included (i) optimizing electrode positioning, (ii) fine-tuning of stimulation patterns and other FES parameters, (iii) adjustments to the mode and frequency of exercise training, and (iv) biofeedback-assisted FES-exercise to promote selective recruitment of fatigue-resistant motor units.

Conclusion

Although the need for further in-depth clinical trials (especially RCTs) was clearly warranted to establish external validity of outcomes, current evidence was sufficient to support the validity of certain techniques for rapid fatigue-reduction in order to promote FES therapy as an integral part of SCI rehabilitation. It is anticipated that this information will be valuable to clinicians and other allied health professionals administering FES as a treatment option in rehabilitation and aid the development of effective rehabilitation interventions.  相似文献   
57.
Constant, systematic exposure to rotenone has been utilized in animal models to induce Parkinsonism. Ellagic acid is a polyphenol with anti-inflammatory and antioxidative properties which is found in numerous natural fruits. Here, we investigated the therapeutic effects of ellagic acid in rotenone-induced toxicity in Drosophila melanogaster evaluating their antioxidant and mitoprotective properties. Adult flies were treated with rotenone and ellagic acid through their diet for 7 days, thereafter markers of neurotoxicity (acetylcholinesterase, monoamine oxidase, tyrosine hydroxylase), antioxidant and oxidative stress markers (hydrogen peroxide, nitric oxide, lipid peroxidation, protein carbonyl contents, catalase, total thiol, and nonprotein thiol) was measured. Mitochondrial respiration was also evaluated in the flies. Survival assay was carried out with both genders of the flies, and we observed a significant increase in the survival rate of flies exposed to both rotenone and ellagic acid when compared with the increased mortality rate in the groups exposed to rotenone alone. The impaired locomotion, altered redox status, and enzymes of neurotoxicity induced by rotenone were significantly ameliorated by ellagic acid to levels comparable to the control. In addition, rotenone-induced complex 1 inhibition and altered bioenergetic state were restored upon ellagic acid supplementation. These findings show the beneficial properties of ellagic acid against pesticides induced toxicity.  相似文献   
58.
Pierce's disease (PD, Xylella fastidiosa) of grapevine is the primary pathogen limiting vinifera grape production in Florida and other regions of the southeastern United States. Quick and accurate detection of PD strains is essential for PD studies and control. A unique random amplified polymorphic DNA (PD1-1-2) was isolated from a PD strain from Florida. Fragment PD1-1-2 was cloned, sequenced, and found to be 1005 bp in length. PCR primers were designed to utilize these sequence data for PD strain detection. One primer set (XF176f–XF954r) amplified a 779-bp DNA fragment from 34 PD strains including seven pathotypes of X. fastidiosa, but not from strains of Xanthomonas campestris pv. campestris, Xan. vesicatoria or Escherichia coli. A second primer set (XF176f and XF686r) amplified a 511-bp fragment specific to 98 PD strains, but not from strains of citrus variegated chlorosis, mulberry leaf scorch, oak leaf scorch, periwinkle wilt, phony peach, or plum leaf scald. Sequence analysis indicated that RAPD fragment PD1-1-2 contains a Ser-tRNA gene. The PD-specific region includes a TaqI restriction site (TCGA) and is 150 bp downstream of the Ser-tRNA gene. Received: 1 March 1999 / Accepted: 5 April 1999  相似文献   
59.
Feathers, nails and beaks of one hundred and twenty common birds in Nigeria, Chicken [50], Ducks [20], Turkeys [15] and Pigeons[35], were examined using the soil plate technique for their mycoflora.15 species of fungi were recovered and they belong to the genera Chrysosporium, Trichophyton, Microsporum, Aspergillus, Fusarium, Mucor, Rhizopus, Penicillium and Trichoderma. Microsporum gypseum was the species most frequently isolated (35% of the samples). The most common genus was Chrysosporium and C. keratinophilum was the species with the highest frequency in the genus (28.3%). The species isolated included potential pathogens and mycotoxin producing fungi (Aspergillus flavus, A. niger, Fusarium oxysporum). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
60.
Rice yellow mottle genus Sobemovirus is an important disease of rice worldwide. Although the virus attacks both upland and lowland rice cultivars, the latter are worse infected. The disease is spread by insect vectors belonging to the families Chrysomelidae, Coccinelidae, and Tettigonidae. It is also transmitted by domestic cattle (Bos spp.), donkeys (Asinus spp.), grass rats (Arvicanthis niloticus), weed species of the family Poaceae, debris, irrigation water and through mechanical inoculation. Six strains of the virus have been reported so far. Rice yellow mottle virus (RYMV) incidence ranges between 5 and 100% and yield losses vary from 20 to 100%. Effective management includes the use of resistant cultivars, control of insect vectors, good sanitation and integrated pest and production management. This paper reviews the current status of the virus, with emphasis on its geographical distribution, characteristics, strains, symptomatology, diagnosis, transmission, host range and management strategies.  相似文献   
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