Background: Toxoplasmosis is caused by the intracellular protozoan Toxoplasma gondii, which has a worldwide distribution.Here, in the first study of asymptomatic infection by this protozoan in the state of Espírito Santo, Brazil, we present an analysis of the prevalence and annual incidence of asymptomatic cases of toxoplasmosis in a rural area of this state.Methods: Plasma samples from 79 individuals who had responded to questionnaires were analyzed by IgG ELISA, and positive cases were subjected to an IgG avidity test.Follow-up lasted one year and consisted of quarterly visits.Results: Of the 79 individuals assessed, 67.1% were positive for IgG anti-Toxoplasma gondii, and the incidence was 6.2 per 100 person-years of observation.No statistically significant association was found between toxoplasmosis and contact with cats or between toxoplasmosis and consumption of pork, mutton or lamb, even if these were undercooked or raw.According to the multivariate analysis, the only risk factor related to infection appears to be increasing age (OR = 1.086).Confirming the data in the literature, the statistical analysis showed that with every additional year of age the risk of contracting toxoplasmosis increase by 8.6%. Conclusion:The inhabitants of rural communities in the mountainous region of Espírito Santo are very exposed to Toxoplasma gondii and know very little about the disease, making them vulnerable to exposure.
Altered gastric physiology in albino rats fed with aqueous extract of Gnetum africana and Talinum triangulare (water leaf) was investigated in gastric hydrochloric acid secretion for the period of 7, 21 and 28 days. The results of mean acid output in the test group that received Gnetum Africana extract alone was significantly increased P <0.05 on day 7 as compared with control group which was same on days 21 and 28. However, the mean acid output was significantly decreased , P <0.05 when compared with control on day 7 and 21 respectively. In the test group that received Gnetum afri-cana and Talinum triangulare extract there was significant decrease in gastric Hydrochloric acid after days 7 and 21 and more significantly decreased in 28 days, P < 0.01 as compared with control. But there was decrease mean hydrochloric acid output in Gnetum africana and Talinum triangulare mixture than Gnetum africana alone. It is concluded that increase consumption of Gnetum africana has the tendency of increasing gastric Hydrochloric acid secretion and likely associated pathology; gastric ulcer.
Aedes aegypti is the principal vector of the yellow fever virus and the four dengue serotypes and its hemorrhag-ic fever viruses. The genetic variability and differentiation of four Aedes aegypti populations from São Luis Island in the Brazilian state of Maranhão was analyzed based on the sequences of a fragment of the mitochondrial ND4 gene. A total of 58 sequences of 337 bps were analyzed, revealing the existence of 10 haplotypes, of which five were considered to be unique. Haplotype diversity for the total population was 0.6273 and nucleotide diversity 0.00748. The haplotype tree produced from the data indicated the presence of two mitochondrial lineages of the dengue vector, one of which was characterized by the H6 haplotype, found only in the population from one site (Raposa), and may represent the recent introduction of this lineage to the island. The results of the AMOVA indicated that the majority of the genetic variation (74.38%) was found within populations. However, the significant Fst value of 0.2572 indicates a certain inter-population differentiation which may result in differences in the vectorial capacity of the insect, its susceptibility to the virus or even resistance to insecticides or other ecological adaptations, all of which may limit the effectiveness of programs for the control of Ae. aegypti.
This study aimed to estimate the occurrence of Aedes aegypti adults at distinct climatic seasons at neighborhoods from the municipality of São Luís, Maranhão State, Brazil, as well as to verify the presence of Dengue virus (DENV) in the specimens collected.A total of 320 properties were visited in eight neighborhoods that were previously randomly chosen.Samplings were made at three periods: dry season/2008, rainy season/2009 and dry season/2009.A total of 563 Ae. aegypti mosquitoes were collected, with 141 of them collected during dry season/2008, 272 during rainy season/2009 and the remnant, during dry season/2009.Specimen were divided into lots and subjected to RT-semi-nested-PCR analysis and virus isolation was carried out using cell culture (C6/36 clone) of Ae. albopictus.The number of adults significantly varied at the neighborhoods of Coréia de Baixo, Lira, João Paulo, and Conjunto Cohatrac I. Molecular analyses of specimens showed no positivity for DENV.At the municipality of São Luís, seasonal climate variation might influence the density of Ae. aegypti adults, however, other factors such as population density, sanitation conditions, and the presence of mosquito breeding sites ought to be assessed as important parameters influencing vector dispersion.
Purpose: Much of the stigma associated with leprosy is caused by disfiguring disabilities following irreversible nerve damage and much of this damage is the end result of leprosy reactions which are either not recognized in early enough stages, not treated appropriately or both. In an effort to improve access to care, to reduce stigma and to integrate leprosy into general health care services, guidelines for standardized treatment in field conditions of the infection itself and of leprosy reactions have been developed and implemented. This has sparked debate among experts concerning the efficacy of treatment protocols for especially leprosy reactions outlined in the guidelines. The principle points of contention are the duration of treatment, dosage and tapering strategies of the drug mainly used, prednisolone. This study investigates on what evidence these guidelines are based. Methods: Electronic databases were used in search of randomized controlled trials and other non-randomized evidence that could shed light on the validity of the strategies advocated and already implemented in most leprosy control programs
Lovastatin, an anti-cholesterol drug, is a potent inhibitor of the enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMG CoA reductase) that catalyses conversion of HMG CoA to mevalonate involved in cholesterol biosynthesis.Lovastatin does not only find a role as anti-cholesterol agent but also plays a key role as an anti-inflammatory agent, cancer cell apoptosis, renal function restoration, treatment for bone disorders etc. Production of statins has been undertaken by Submerged Fermentation (SmF) and Solid State Fermentation (SSF) by using fungi.In view of the advantages of SSF over SmF, the focus has shifted to production by SSF in recent years.The use of various agro based wastes as substrates has been proven.With recent developments in molecular biology and genome studies it has been able to decode genetic aspects of lovastatin gene expression levels.This review gives an insight into works reported on lovastatin production by SSF, various substrates employed, mutation studies, optimisation parameters, molecular studies and medical application of lovastatin.
Our group analyzed species of Anopheles of the subgenus Nyssorhynchus (An.darlingi, An. marajoara, An. oswaldoi, An. benarrochi, An. triannulatus and An.rangeli) and a single species of the subgenus Anopheles (An.mattogrossensis), originating in the Amazon, based on the mitochondrial DNA control region.The fragment had 381 pb and the nucleotide composition in A+T ranged from 85.8 to 89.5%.DNA polymorphism analysis of the species detected 15 haplotypes, with the presence of 81 polymorphic loci, 95 mutations, haplotypic divergence of 0.879, nucleotide diversity of 0.06507, nucleotide differences pair the pair mean of 23.1749, and the observed and expected variances of 113.840 and 8.33, respectively.The genetic distance among the Anopheles species varied from 0.06 to 1.37%.An. oswaldoi and An.rangeli were the most similar, with nucleotide divergence of 0.17%.The An. benarrochi populations of Ji-Paraná and Bolivia showed nucleotide divergence of 0.06%.An. darlingi, An. marajoara and An.triannulatus presented nucleotide divergences of 0.35% between An. triannulatus and An.darlingiand of 0.47% between An. darlingi and An.marajoara.This data showed ample interspecific nucleotide variation, though with low nucleotide divergence.The cladogram separated the species of the subgenus Nyssorhynchus and those of the subgenera Cellia and Anopheles, with 98% bootstrap.The region control data did not show strong phylogenetic support, as indicated by the transition/transversion mean rate (0.4643), which is necessary for increasing fragment size and using other more conservative genes for greater inference concerning the phylogeny of the Anopheles species of the subgenus Nyssorhynchus.
We conducted a cross-sectional parasitological survey for Human African Trypanosomiasis (HAT) among the inhabitants of 12 villages in Chama District, Luangwa valley, in the Eastern Province of Zambia from 21 August to 4 September 2010. These villages have had a history of being the origin of HAT cases occasionally diagnosed and treated at Chama District hospital. Historically Luangwa valley has been known to be a significant focus for sleeping sickness transmission in Zambia [1]. HAT in Zambia is caused by the haemoflagellate Trypanosoma brucei rhodesiense.
This study aimed to investigate the malaria infection prevalence and predisposing risk factors among some pregnant women in Greater Khartoum area, Sudan.Following informed consent, eight hundred thirty six pregnant women were interviewed and thick blood films were prepared and examined for malaria parasites.Parasite densities were determined by counting parasites against 200 leukocytes assuming a white blood cells count of 6,000/µl.PCR was performed using outer and nested primers to enhance detection of parasitemia below the microscopy threshold, after DNA extraction by chelex method.Microscopy and species-specific PCR results showed that 26.2% and 56.5% of women were positive respectively.Low parity and young-aged pregnant women were significantly associated with parasitemia (p=0.001,0.004).Second trimester pregnancy [adjusted odd ratio (aOR), 3.2 (95% CI, 2.9-5.8,)] and season of antenatal visit [(aOR), 1.7 (95% CI, (0.9-1.1)] constituted a significant risk factor for contracting malaria.In a multivariate analysis, mothers <20 years [(aOR), 2.4 (95% CI, 1.3-3.0)],first and second pregnancies [(aOR), 2.0 (95% CI, 1.1-1.9)],povertyrelated factors (low-income, illiteracy) were independent predictors for P. falciparum infection.Pregnancy-associated P. falciparum malaria is prevalent among Sudanese pregnant women with evidence of close correlation to low parity, young age and socioeconomic status.
Even though treatment of symptomatic cases as well as improving hygiene and sanitation conditions decrease giardiasis in underdeveloped and/or developing countries, Giardia duodenalis infection is still frequently encountered especially in children living in crowded conditions leading to public health problems. We studied the prevalence of G. duodenalis infection in 274 asymptomatic Thai boy orphans, living in/around the Bangkok metropolitan area, by use of direct fecal smear and formalin-ethyl acetate techniques. This was done to explore our hypothesis that children with asymptomatic giardiasis, who are not likely to be treated, have a high potential for spreading this pathogen. Positive Giardia cases were further genotyped by 2 genes: small subunit ribosomal RNA (ssrRNA) and glutamate dehydrogenase (gdh) to determine the distribution of each G. duodenalis assemblage. Positive G. duodenalis infection was 11.67 % and revealed at 10.63%, 12% and 15%, in PK, TMK, and MHK orphanages, respectively. The overall parasitic infection, including Giardia, was 48.54% consisting mostly of non-pathogenic organisms i.e. Blastocystis hominis, Entamoeba coli, Endolimax nana, Entamoeba histolytica-like, Chilomastix mesnili, Trichuris trichiura, Hymenolepis nana, Strongyloides stercoralis and Hookworm. Fourteen (70 %) and 4 (20 %) out of the 20 positive Giardia samples could be amplified by ssrRNA and gdh genes, respectively; three belonged to the sub-assemblage BIV and only one indicated sub-assemblage AII. Thus children infected with sub-assemblage BIV isolate are more common in this study. In conclusion, we focused on asymptomatic giardiasis children, hitherto unrecognized, who consistently contaminate their environments with cysts. We favor not only treating these children to eradicate the source of the infection, but also to encourage an active surveillance program consisting of highly sensitive methods to identify silent giardiasis cases. In addition to these 2 strategies, a continuous fruitful health education program for all stakeholders is another crucial tool. These actions will benefit the control of human giardiasis and reduce public health problems.
Four populations of Aedes aegypti from Manaus were studied, using allozymes and RAPD loci, to determine intra-and interpopulation genetic variability and differentiation and to compare genetic structure parameters assessed with both markers.Five RAPD primers produced 52 polymorphic fragments, whereas only seven of 18 isozyme loci were polymorphic.The population from Praça 14 was the most polymorphic (P= 94.23% and P= 55.6%); while those from Coroado (P= 82.69% and P= 44.40%) and from Cidade Nova (P= 84.61% and P= 44.40%) were the least polymorphic, for both RAPD and isozymes respectively.The observed heterozygosity was higher between populations (Ho= 0.33 -0.38) as assessed by RAPD.Wright's F statistics showed an F is value higher than F st (F is = 0.164 > F st = 0.048).AMOVA indicated that 95.12% of the genetic variability is intrapopulational.Even so, both of the genetic markers evaluated showed a relatively high gene flow ((N m = 15.15), and possibly are still random couplings, although the F is value was not low.The genetic distance between populations was similarly low for both markers: RAPD (0.012 -0.016) and Isozymes (0.003 -0.016).These results show that as assessed by both markers, the populations are genetically similar, and that isozymes (codominant) are the most efficient to detect the population genetic structure.Although isozymes revealed less genetic diversity than RAPDs, the estimated levels of genetic distance were identical.
The T. cruzi strains are a complex of multi-clonal populations that affects the brain with more severity in children or young animals, suggesting that functional immaturity of the blood brain barrier (BBB) might be involved in T. cruzi infection in the brain.This study investigated relationships between BBB permeability and T. cruzi infection in the rat brain.The animals were inoculated with one of 3 strains of T. cruzi at 30 days of age, and BBB permeability was increased by subcutaneous kainic acid injection in half of the infected animals.The animals were sacrificed at 13 days of infection.The brain sections were stained with hematoxylin and eosin.The all brains of the infected animals with and without kainic acid showed both glial nodules and perivascular infiltrates due to T. cruzi infection.Number of these glial nodules was counted in each rat, and statistical comparison indicated that kainic acid-treatment significantly increased mean numbers of glial nodules in all of the rats infected with the 3 strains.The results indicated that the increased BBB permeability was one of the factors for facilitation of the entry of T. cruzi into the brain.
We primarily identified Leishmania donovani parasites from eastern Sudan using species-specific primers that amplify a whole length minicircle.Based on the amplification of a cytochrome oxidase II fragment (COII), heteroduplex analysis (HDA) was performed.In HDA, the appearance of the extra bands with molecular weights higher than 540 bp indicates the presence of mismatched bases in the selected samples.Such bands were detected when hybridization was between reference strains and clinical isolates, as well as between the reference strains themselves, while no heteroduplexes were detected between the clinical isolates.Moreover, an RFLP assay using the restriction enzyme Ssp1 was performed on the original 540 bp products to discern an A-G transition, which differentiates between members of the Leishmania (L) infantum and those of Leishmania (L) donovani subspecies.The proposed minicircle genes-based analysis was rapid and easy to perform method for the characterization of Leishmania donovani complex isolates and with a potential to be extended to characterization of other species of Leishmania.
A novel form of human malaria Plasmodium knowlesi has been identified in small epidemic foci occurred during the last decade in Malaysia. Based on a review of the available literature data, the Authors underline the diagnostic importance of molecular biology examinations performed with primers which are specific of Plasmodium knowlesi, since the standard hemoscopy may fail in distinguishing Plasmodium knowlesi from Plasmodium malariae, due to their similar appearance. P. knowlesi has been reported as a causative parasite agent of life-threatening and even lethal forms of malaria. In humans, its clinical picture is more severe a compared to that of P. malariae, since the disease is characterized by a greater parasitemia, versus that is referred in the course of P. malariae disease. The most effective carrier of P. knowlesi is represented by the mosquito Anopheles leucosphyrus, which is attracted by both humans and monkeys. Among primates, the natural hosts of P. Knowlesi are known until now and have been represented by Macaca fascicularis and Macaca nemestina, while other monkeys including Saimiri scirea and Macaca mulatta, which cannot become infected. These might be useful in eventual experimental models. When facing the potentially severe evolution of human disease by P. knowlesi, we remark the key role played by a prompt disease recognition, which is expected to be more easy and obvious in patients followed in endemic countries at elevate risk, but should be carefully implemented for subjects coming back to health care services of western countries, presenting with a number of typical signs and symptoms of malaria, after travelling in South-East Asia where they were engaged in staying or making excursions in the tropical forest. In these last cases, both diagnosis and treatment should be prompt, timely, and appropriate. According to literature data, in non-severe human cases the old and trivial chloroquine remained very effective against P. knowlesi, achieving the disappearance of signs and symptoms in 96% of cases within the first day of pharmacological therapy. On the ground of the emerging epidemiological figures, P. knowlesi was added to Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium falciparum, as the fifth etiological agent of human malaria. During the next years, it will become mandatory to plan an adequate surveillance programme of the epidemiological evolution of this novel form of human malaria, paying also maximum attention to the clinical presentation of patients affected by P. knowlesi malaria, which are expected to suffer from a more severe clinical course, according to the time elapsed from the appearance of the early signs and symptoms. Some preliminary clinical figures suggest that a greater severity is related to an increased parasitemia, and parallels the increased interhuman infectious passages of parasites.
A non-compartment pharmacokinetic model was used to evaluate the potential of antimalarial drugs to influence malaria transmission using the ratio of sex specific gametocyte half-lives male:female-the gametocyte maleness index (GMI), and the ratio of the sex specific area inscribed by the plot of gametocyte sex density versus time curves AUCmg:AUCfg-the gametocyte maleness load index (GMLI).Data on gametocyte sexes collected in children with symptomatic Plasmodium falciparum malaria who were treated with various antimalarial drugs in an endemic area were examined using the two indices.Both GMI and GMLI were positively correlated (r = 0.71, P < 0.0001) and with 95% limits of agreement of -9.7 to 13.8 using Altman-Bland plot.Based on the assumption that, a male-biased sex ratio, if gametocytaemia is low, may increase mosquito infectivity, both GMI and GMLI, consistently gave index ratios > 1 for 4aminoquinolines and antifolates suggesting potential for increasing the chance of mosquito infectivity.By contrast, artesunate and artemisinin-based combination therapies (ACTs), artemether-lumefantrine, and artesunate-amodiaquine, and a non-ACT, amodiaquine plus sulfalene-pyrimethamine, had ratios < 1 suggesting potential for reducing the chance of mosquito infectivity.The advantages and drawbacks of using these indices as tools in assessing the influence of antimalarials on transmission potentials in endemic areas of malaria are discussed.
Strain diversity may play a role in delaying development of protective immunity in endemic areas. We evaluated genetic diversity of Plasmodium falciparum infected children before being treated with Sulphadoxine Pyrimethamine (SP) and Coartem™ in Southeastern Tanzania. Allelic diversity of P. falciparum strains were determined in order to further assist in correct estimation of recrudescent and new infections. P. falciparum isolated from 300 children aged 1-59 months was used in the study, where nested PCR followed by Restriction Fragment Length Polymorphism (RFLP) of highly polymorphic Merozoite surface protein 2 (msp2) was employed to understand the genetic diversity of the parasites population. Frequency of msp2 gene alleles was calculated and further associated with multiplicity of infection of children under five years of age. A total of 71 and 83 different msp2 alleles were found in Rufiji and Ulanga districts respectively. Children infected with either FC27 or 3D7 allelic type in Rufiji were 42% single, 55.3% double and 2.7% triple, while in Ulanga, 36.7% single, 62% double and 1.3% triple infections. Mean numbers of multiplicity of infections (MOI) in Rufiji and Ulanga were 1.6 and 1.3, respectively. These findings show a high genetic diversity of P. falciparum strains in study areas and low MOI could reflect production of susceptible parasites that immune response can accommodate or can be cleared by the drugs. Furthermore, 3D7 allelic type of msp2 gene was more prevalent than FC27 in Ulanga district, indicating association between msp2 allelic type and disease severity, hence predict possible vaccine candidate in the future.
The need for new and effective/efficient antibacterial therapeutics and diagnostics is necessary if we want to be able to maintain and improve the protection against pathogenic bacteria.Bacteria are becoming increasingly resistant to traditionally used antibiotics and as a result are a major health concern.The number of deaths and hospitalizations due to bacteria is increasing.Current methods of bacterial diagnostics are inefficient as they lack speed and ultra sensitivity and cannot be performed on site.This is where nanomedicine is playing a vital role.The discovery of new and innovative materials through the improvement in fabrication techniques has seen the establishment of an influx of novel antibacterial therapeutics and diagnostics.The goal of this review is to highlight the research that has been done through the implementation of nanomaterials and nanotechnologies for antibacterial medical therapeutic and diagnostic.
Malaria parasite multi-drug resistance poses serious health problems in tropical countries.The aim of this study was to assess the Sulfadoxine-pyrimethamine (S/P) resistance of Plasmodium falciparum parasite in central Sudan, using the molecular markers.The genotying of P. falciparum parasite from forty-four patients using RFLP and PCR showed that the polymorphism of dhfr gene was in codons 51, 59 and 108.In codon 51; two strains (4.5%) were mutant type; 3 (6.8%)were found as mixed infection (both mutant and wild types) and 28 (63.6%) were found as wild type.One sample (2.2 %) was dhfr 59 mutant and 31 (70.4.%) were wild type, while 14 (31.8%) were dhfr 108 mutant; three (6.8%) were found as mixed infection and 24 (54.5%) were wild types.The Screening of dhps 540 polymorphisms of the gene revealed that 2 (4.5%) were found as mixed infection, and 42 (95.5%)as wild type.Fifteen samples were analyzed for Pfcrt T76, and Pfmdr-1 Y 86 for CQ resistant polymorphisms from the current study, the result showed that 33.3% were found to be mutant at dhfr 108 and PfcrtT76 genes reflecting the link between dhfr108 and Pfcrt76 genes.In conclusion, the polymorphism in the dhfr and dhps genes in central Sudan are increasing, but less abundant compared to the neighboring countries.However, the current studies indicate the link between dhfr108 and Pfcrt76 genes.Therefore, further study is need for using the S/P in areas that confirmed with chloroquine resistant strains.
Endomyocardial fibrosis (EMF) is a common restrictive cardiomyopathy of unknown etiology, endemic to regions close to the equator.According to previously published reports, the disease affects only the right ventricle (RV) 10-28% of patients with endomyocardial fibrosis.The aims of this study were to determine the prevalence of EMF among patients with heart failure in Equatorial Guinea, and to describe its clinical manifestations.We used transthoracic echocardiography to determine the prevalence of EMF among 50 patients with newly diagnosed heart failure.We compared the demographic data, clinical features and eosinophilic counts in patients with EMF and patients with other forms of heart failure.During a study period of nine months ten patients were diagnosed with EMF, accounting for 20% of the patients diagnosed with heart failure.Curiously, all ten patients had exclusive right-sided disease.The average time from the onset of symptoms to diagnosis was 6.1±2.0 years (range 3-9 years), implicating a much better prognosis than previously reported.Eosinophil count was not higher in patients with EMF when compared to other patients with heart failure.The exclusive involvement of the right ventricle in ten consecutive patients, and the relatively long survival after the onset of symptoms, hint towards a specific variant of the disease in Equatorial Guinea.
