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21.
BackgroundReduced visual function is associated with diminished quality of life as well as decreased physical and mental health. Poor visual function related to cataracts is also a risk factor for falls and traffic accidents, which may lead to hospital admissions and limit independence.ObjectiveTo evaluate patients'' satisfaction, visual functions and spectacle independence among patients in the Central Region of Ghana who had cataract surgery in one eye.MethodsA hospital-based prospective cohort study was carried out on 146 patients booked for cataract surgery: 16 were lost through follow-ups whilst 130 completed the study. Visual functions including visual acuity, contrast sensitivity, stereopsis and colour vision were assessed before and after a month of cataract surgery. Objective and subjective refractions were performed to determine the post-surgery refractive status of the participants. Participants completed the NEI-VFQ 25 questionnaire and the scores obtained were used as a construct of their satisfaction.ResultsThe NEI-VFQ 25 questionnaire scores indicated patients'' satisfaction was high with an average quality of life score of 77.46. Patients satisfaction was strongly correlated with contrast sensitivity (r=0.653, p<0.001) but moderately correlated with visual acuity (r=-0.554, p<0.001), stereopsis (r=0.490, p<0.001) and colour vision (r=0.466, p<0.001). Contrast sensitivity was a better predictor of patients'' satisfaction than visual acuity and stereopsis. Spectacle independence at distance was achieved in only 44.6% of the participants and 5.4% at near. There was a significant (p>0.001) association between spectacle independence and the two types of cataract surgery performed which included Small Incision Cataract Surgery (SICS) and Extracapsular Cataract Extraction (ECCE). Among those who were spectacle independent, 53.4% of them were low vision patients.ConclusionSatisfaction of patients after cataract surgery was high but was greatly influenced by visual functions with contrast sensitivity being a better predictor of satisfaction than visual acuity and stereopsis. Spectacle independence after cataract surgery was low at distance and extremely low at near. The type of cataract surgery performed influenced thespectacle independence.  相似文献   
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Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti‐Trypanosoma, anti‐Leishmania, and anti‐Plasmodium activities in vitro and investigated their mechanisms of action. Twenty‐three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC50 values less than 20 μg/ml. Eleven extracts showed high anti‐Trypanosoma activity with Bidens pilosa whole plant and Morinda lucida leaf extracts recording the highest activities. Their IC50 (selectivity index [SI]) values were 5.51 μg/ml (35.00) and 5.96 μg/ml (13.09), respectively. Nine extracts had high anti‐Leishmania activity with Annona senegalensis and Cassia alata leaf extracts as the most active. Their IC50 (SI) values were 10.8 μg/ml (1.50) and 10.1 μg/ml (0.37), respectively. Six extracts had high anti‐Plasmodium activity with the leaf and stem‐bark extracts of Terminalia ivorensis recording the highest activity. Their IC50 (SI) values were 7.26 μg/ml (129.36) and 17.45 μg/ml (17.17), respectively. Only M. lucida at 25 μg/ml induced significant apoptosis‐like cell death in Trypanosoma parasites. Anti‐Leishmania active extracts induced varying morphological changes in Leishmania parasites such as multiple nuclei and/or kinetoplast, incomplete flagella division, or nuclear fragmentation. Active extracts may be potential sources for developing new chemotherapy against these infections.  相似文献   
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The association between the clinical outcome of chloroquine treatment and mutations in the putative Plasmodium falciparum chloroquine resistance transporter (Pfcrt) gene at codon 76 and multidrug resistance gene 1 (Pf mdr1) at codon 86 were investigated among 406 children with uncomplicated malaria presenting at five sentinel health centres in Ghana. Presence of mutations in isolates taken at pre-treatment and on day of recurrence of parasites was detected using PCR followed by RFLP techniques. The prevalence of Pfcrt T76 mutants was 80% at Hohoe, 46% at Navrongo, 98% at Tarkwa, 61% at Sunyani and 46% at Yendi. The prevalence of the mutant Pfmdr1 at Hohoe, Navrongo, Tarkwa, Sunyani and Yendi were 78, 58, 95, 53 and 42%, respectively. Significant association between the Pfcrt mutation and treatment outcome was observed at Hohoe and Sunyani (p < 0.05), but not at Navrongo, Tarkwa or Yendi (p > 0.05). Similarly, a statistical significant association between Pfmdr1 86 and treatment failures was observed at Hohoe and Sunyani (p < 0.05) but not at the other three sites. A positive correlation was found between mutant Pfcrt prevalence only and treatment failures with a Spearman's rho-value of 0.872 and a p-value = 0.027. All parasite isolates from samples taken at recrudescence from patients with chloroquine treatment failures were found to have both Pfcrt and Pfmdr mutations.  相似文献   
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This report shows the impact of a pentavalent vaccine that includes Haemophilus influenzae type b (Hib) conjugate vaccine on bacterial meningitis in children younger than 5 years in Ghana. A review of the first 3 years of a pediatric bacterial meningitis surveillance program, started in August 2001 in Accra, Ghana, was undertaken. There was a significant reduction, P = 0.042 and 0.017, in percentage of purulent meningitis in children younger than 1 year, comparing the first year when the vaccine was introduced, to the second and third years, respectively.  相似文献   
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Journal of Autism and Developmental Disorders - Individuals with developmental disabilities (DD) are twice as likely to have obesity than non-disabled individuals. Replacing the consumption of...  相似文献   
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We studied the malaria transmission dynamics in Kassena Nankana district (KND), a site in northern Ghana proposed for testing malaria vaccines. Intensive mosquito sampling for 1 year using human landing catches in three micro-ecological sites (irrigated, lowland and rocky highland) yielded 18 228 mosquitoes. Anopheles gambiae s.l. and Anopheles funestus constituted 94.3% of the total collection with 76.8% captured from the irrigated communities. Other species collected but in relatively few numbers were Anopheles pharoensis (5.4%) and Anopheles rufipes (0.3%). Molecular analysis of 728 An. gambiae.s.l. identified Anopheles gambiae s.s. as the most dominant sibling species (97.7%) of the An. gambiae complex from the three ecological sites. Biting rates of the vectors (36.7 bites per man per night) were significantly higher (P<0.05) in the irrigated area than in the non-irrigated lowland (5.2) and rocky highlands (5.9). Plasmodium falciparum sporozoite rates of 7.2% (295/4075) and 7.1% (269/3773) were estimated for An. gambiae s.s. and An. funestus, respectively. Transmission was highly seasonal, and the heaviest transmission occurred from June to October. The intensity of transmission was higher for people in the irrigated communities than the non-irrigated ones. An overall annual entomological inoculation rate (EIR) of 418 infective bites was estimated in KND. There were micro-ecological variations in the EIRs, with values of 228 infective bites in the rocky highlands, 360 in the lowlands and 630 in the irrigated area. Approximately 60% of malaria transmission in KND occurred indoors during the second half of the night, peaking at daybreak between 04.00 and 06.00 hours. Vaccine trials could be conducted in this district, with timing dependent on the seasonal patterns and intensity of transmission taking into consideration the micro-geographical differences and vaccine trial objectives.  相似文献   
29.
Demographics and health practices of 2,232 pregnant women in rural northeastern Ghana and characteristics of their 2,279 newborns were analyzed to determine benefits associated with intermittent preventive treatment (IPTp), antenatal care, and/or bed net use during pregnancy. More than half reported bed net use, 90% reported at least two antenatal care visits, and > 82% took at least one IPTp dose of sulfadoxine-pyrimethamine. Most used a bed net and IPTp (45%) or IPTp alone (38%). Low birth weight (< 2,500 grams) characterized 18.3% of the newborns and was significantly associated with female sex, Nankam ethnicity, first-born status, and multiple births. Among newborns of primigravidae, IPTp was associated with a significantly greater birth weight, significantly fewer low birth weight newborns, improved hemoglobin levels, and less anemia. Babies of multigravidae derived no benefit to birth weight or hemoglobin level from single or multiple doses of sulfadoxine-pyrimethamine during pregnancy. No differences or benefits were seen when a bed net was the only protective factor.  相似文献   
30.
BACKGROUND: Usefulness of sulfadoxine-pyrimethamine as first-line therapy for uncomplicated Plasmodium falciparum malaria and intermittent preventive treatment in pregnancy throughout sub-Saharan Africa is compromised by the spread of dhfr alleles associated with pyrimethamine resistance. A predominant haplotype associated with the N51I+C59R+S108N triple-mutant dhfr allele has been reported recently in 4 African countries. A more comprehensive picture of the evolution of this mutant allele in Africa is lacking. METHODS: Seventy-five P. falciparum isolates carrying the wild-type dhfr allele and 204 carrying the triple-mutant dhfr allele from 11 African countries were selected. The genetic diversity of the chromosomes bearing these alleles was analyzed with 4 microsatellite markers closely linked to the dhfr gene. RESULTS: Seventy-three different 4-locus haplotypes carrying the wild-type dhfr allele were found. By contrast, 175 (85%) of 204 isolates carrying the triple-mutant dhfr allele shared a unique haplotype, identical to the one identified in Thailand. For the remaining triple-mutant isolates and one isolate with the quadruple-mutant dhfr allele (N51I+C59R+S108N+I164L), haplotypes were closely related to the predominant haplotype by mutation or recombination. CONCLUSIONS: Migration of parasites carrying an ancestral triple-mutant dhfr allele drives the spread of dhfr alleles associated with pyrimethamine resistance throughout West and Central Africa.  相似文献   
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