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1.
Nature ; 489(7416): 443-6, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22895189

RESUMO

Malaria causes approximately one million fatalities per year, mostly among African children. Although highlighted by the strong protective effect of the sickle-cell trait, the full impact of human genetics on resistance to the disease remains largely unexplored. Genome-wide association (GWA) studies are designed to unravel relevant genetic variants comprehensively; however, in malaria, as in other infectious diseases, these studies have been only partly successful. Here we identify two previously unknown loci associated with severe falciparum malaria in patients and controls from Ghana, West Africa. We applied the GWA approach to the diverse clinical syndromes of severe falciparum malaria, thereby targeting human genetic variants influencing any step in the complex pathogenesis of the disease. One of the loci was identified on chromosome 1q32 within the ATP2B4 gene, which encodes the main calcium pump of erythrocytes, the host cells of the pathogenic stage of malaria parasites. The second was indicated by an intergenic single nucleotide polymorphism on chromosome 16q22.2, possibly linked to a neighbouring gene encoding the tight-junction protein MARVELD3. The protein is expressed on endothelial cells and might therefore have a role in microvascular damage caused by endothelial adherence of parasitized erythrocytes. We also confirmed previous reports on protective effects of the sickle-cell trait and blood group O. Our findings underline the potential of the GWA approach to provide candidates for the development of control measures against infectious diseases in humans.


Assuntos
Resistência à Doença/genética , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Malária Falciparum/genética , Sistema ABO de Grupos Sanguíneos , Anemia Falciforme , Estudos de Casos e Controles , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 16/genética , Gana , Humanos , Malária Falciparum/parasitologia , Malária Falciparum/patologia , Proteínas de Membrana/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Polimorfismo de Nucleotídeo Único/genética
2.
World J Microbiol Biotechnol ; 30(3): 1129-34, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24142427

RESUMO

Competitiveness for nodulation is a desirable trait in rhizobia strains used as inoculant. In Sinorhizobium meliloti 1021 mutation in either of the trehalose utilization genes thuA or thuB influences its competitiveness for root colonization and nodule occupancy depending on the interacting host. We have therefore investigated whether mutation in the thuA ortholog in Mesorhizobium loti MAFF303099 also leads to a similar competitive phenotype on its hosts. The results show that M. loti thuA mutant Ml7023 was symbiotically effective and was as competitive as the wild type in colonization and nodule occupancy on Lotus corniculatus and Lotus japonicus. The thuA gene in M. loti was not induced during root colonization or in the infection threads unlike in S. meliloti, despite its induction by trehalose and high osmolarity in in vitro assays.


Assuntos
Proteínas de Bactérias/metabolismo , Lotus/microbiologia , Mesorhizobium/enzimologia , Mesorhizobium/crescimento & desenvolvimento , Nodulação , Trealose/metabolismo , Proteínas de Bactérias/genética , Mesorhizobium/metabolismo , Mesorhizobium/fisiologia , Mutação , Raízes de Plantas/microbiologia , Simbiose
3.
Clin Case Rep ; 12(5): e8835, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38681028

RESUMO

Key Clinical Message: In young women presenting with atypical features of intracerebral hemorrhage, metastatic choriocarcinoma should be considered as a differential diagnosis. In resource-poor settings, a high index of suspicion and serum ß-hCG are crucial for diagnosis. Abstract: Intracerebral hemorrhage in the young is rarely caused by metastatic choriocarcinoma. Diagnosis of this condition may be particularly challenging in resource-poor settings where access to diagnostic technologies may be limited. We present a case series of three young females diagnosed with metastatic choriocarcinoma after initially presenting with intracerebral hemorrhage, each demonstrating unique clinical manifestations. We aim to highlight the diagnostic considerations in the management of this infrequently encountered cause of intracerebral hemorrhage, especially in resource-constrained settings. Case 1 involved a 21-year-old woman who was initially diagnosed with intracerebral hemorrhage likely of tumoral origin from an unknown primary source. Further evaluation revealed extremely high levels of ß-hCG and features suggestive of an intrauterine malignancy, which led to a diagnosis of metastatic choriocarcinoma. This further became complicated by pulmonary embolism. Unfortunately, she succumbed to respiratory failure during treatment. Case 2 is a young woman who presented to the emergency unit and was managed as a case of lobar intracerebral hemorrhage. Further checks revealed a previous history of hysterectomy done on account of placental site trophoblastic tumor, which promoted an evaluation for choriocarcinoma. Case 3 involved a 20-year-old patient who initially presented with headache and vomiting. An enhanced magnetic resonance imaging showed a large subacute right temporal occipital subependymal hemorrhage with mass effect. After probing further, we discovered that she underwent exploratory laparotomy for suspected ruptured ectopic gestation, which later turned out to be a gestational trophoblastic neoplasia. After further evaluation a diagnosis of choriocarcinoma with brain metastasis. Our case series emphasizes the importance of having a high index suspicion in young females who present with atypical features of ICH. The varied clinical scenarios highlight the challenges in diagnosing young females. It also underscores the critical role of serum ß-hCG, especially in resource-limited settings where biopsies are not readily available. Building a repository of these diverse manifestations is essential for increasing the index of suspicion and ultimately improving patient outcomes.

4.
J Bacteriol ; 195(17): 3797-807, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23772075

RESUMO

The thu operon (thuEFGKAB) in Sinorhizobium meliloti codes for transport and utilization functions of the disaccharide trehalose. Sequenced genomes of members of the Rhizobiaceae reveal that some rhizobia and Agrobacterium possess the entire thu operon in similar organizations and that Mesorhizobium loti MAFF303099 lacks the transport (thuEFGK) genes. In this study, we show that this operon is dedicated to the transport and assimilation of maltitol and isomers of sucrose (leucrose, palatinose, and trehalulose) in addition to trehalulose, not only in S. meliloti but also in Agrobacterium tumefaciens. By using genetic complementation, we show that the thuAB genes of S. meliloti, M. loti, and A. tumefaciens are functionally equivalent. Further, we provide both genetic and biochemical evidence to show that these bacteria assimilate these disaccharides by converting them to their respective 3-keto derivatives and that the thuAB genes code for this ketodisaccharide-forming enzyme(s). Formation of 3-ketotrehalose in real time in live S. meliloti is shown through Raman spectroscopy. The presence of an additional ketodisaccharide-forming pathway(s) in A. tumefaciens is also indicated. To our knowledge, this is the first report to identify the genes that code for the conversion of disaccharides to their 3-ketodisaccharide derivatives in any organism.


Assuntos
Agrobacterium tumefaciens/metabolismo , Maltose/análogos & derivados , Óperon , Sinorhizobium meliloti/metabolismo , Sacarose/metabolismo , Álcoois Açúcares/metabolismo , Trealose/metabolismo , Agrobacterium tumefaciens/química , Agrobacterium tumefaciens/genética , Transporte Biológico , Biotransformação , Teste de Complementação Genética , Maltose/metabolismo , Redes e Vias Metabólicas/genética , Sinorhizobium meliloti/química , Sinorhizobium meliloti/genética , Análise Espectral Raman
5.
Health Sci Rep ; 6(4): e1177, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37008811

RESUMO

Background and Aims: Hemolysis is a fundamental feature of sickle cell disease (SCD) contributing to the vaso-occlusive crisis of patients. The objectives of the study were to assess the link between hemolysis proteins and hematological parameters, and to validate cystatin C (CYS C) as a potent renal marker in diagnoising SCD. Method: Here, a cross-sectional study carried out at the pediatric SCD clinic of the Komfo Anokye Teaching Hospital comprised 90 SCD children (HbSC, HbSF, and HbSS). ANOVA, t-test, and Spearman's rank correlation analysis were done. Elevated proteins levels were compared to standard values; alpha-1 microglobulin (A1M) (1.8-65 µg/L), CYS C (0.1-4.5 µmol/L), and haemopexin (HPX) (500-1500 µg/mL). Results: The mean (standard deviation) age of participants was 9.830 (±0.3217) years, and 46% of them were males. From simple descriptive analysis, we observed that all but one patient had their HPX level below the reference range (<500 µg/mL). Here, A1M levels were shown to be within the appropriate reference range for all the patients except few patients. CYS C levels were also all within the required reference values. A Spearman's rank correlation test between full blood count and HPX generally suggested a weak but positive correlation; RBC (coef. = 0.2448; p = 0.0248), HGB (coef. = 0.2310; p = 0.030), hematocrit (coef. = 0.2509; p = 0.020), and platelet (coef. = 0.1545; p = 0.160). Mean corpuscular volume (coef. = -0.5645; p = 0.610) had a stronger but negative correlation with HPX. This study depicts a positive and stronger association between CYS C and HPX levels (coef. = 0.9996; p < 0.0001), validating the use of CYS C as a useful marker of renal function in persons with SCDs. Conclusion: In the present study, we show that A1M levels were normal for most of the patients, hence CYS C levels are not alarming in this study. Further, there exists a correlation between hemolysis scavenger proteins and hematological parameters.

6.
Appl Environ Microbiol ; 77(15): 5513-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21652738

RESUMO

Very little is known about rhizobia that form nodules on Thermopsis spp. We report the isolation of a Mesorhizobium huakuii strain with a unique nodA gene that form nodules on Thermopsis lupinoides in Kamtchatka, Russia. The isolate did not form nodules on Thermopsis chinensis or Thermopsis caroliniana, which suggests it may be host specific.


Assuntos
Aciltransferases/genética , Fabaceae/microbiologia , Gleiquênias/microbiologia , Mesorhizobium/genética , Aciltransferases/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Genes Bacterianos , Variação Genética , Mesorhizobium/enzimologia , Mesorhizobium/isolamento & purificação , Dados de Sequência Molecular , Fixação de Nitrogênio , Filogenia , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Simbiose/genética
7.
BMC Res Notes ; 12(1): 802, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831048

RESUMO

OBJECTIVE: The association between unbalanced iron indices and the conditions of schizophrenia are not well understood. Liver dysfunction which has been linked to iron metabolism might be a contributing factor. This case-control study evaluated serum iron indices and liver function in treatment-naïve schizophrenia patients and those already on treatment at the Psychiatric Department of the Komfo Anokye Teaching Hospital (KATH), Kumasi-Ghana. RESULTS: The mean age of the respondents was 39.6 ± 0.8 years. Increased levels of serum iron, TS, AST, ALT and AST:ALT ratio and lower levels of UIBC, TIBC, Transferrin, and log Ferritin:AST ratio levels were observed among the treatment-naïve group compared to the control. The treatment-naïve and treatment groups showed significantly higher serum AST:ALT ratio, and lower log10ferrtin:AST ratio than the healthy controls. There was a significant correlation between log10ferritin and AST, and log10ferritin and GGT in both treatments (r = 0.343; p = 0.003, and r = 0.502; p = 0.001 respectively) and treatment-naïve groups (r = 0.348; p = 0.002, and r = 0.614; p < 0.001 respectively). Percentage transferrin saturation correlated significantly with GGT only, in the treatment-naïve group (r = 0.667; p < 0.001), and ALT and GGT in the treatment group (r = 0.252; p = 0.030 and r = 0.646; p = 0.014 respectively).


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Ferritinas/sangue , Sobrecarga de Ferro/sangue , Ferro/sangue , Esquizofrenia/complicações , Adulto , Alanina Transaminase/análise , Aspartato Aminotransferases/análise , Estudos de Casos e Controles , Feminino , Ferritinas/análise , Gana , Humanos , Sobrecarga de Ferro/complicações , Fígado/metabolismo , Testes de Função Hepática , Masculino , Esquizofrenia/sangue , Transferrina/química , Transferrina/metabolismo
8.
Syst Appl Microbiol ; 40(1): 51-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27939530

RESUMO

Rhizobia nodulating native Astragalus and Oxytropis spp. in Northern Europe are not well-studied. In this study, we isolated bacteria from nodules of four Astragalus spp. and two Oxytropis spp. from the arctic and subarctic regions of Sweden and Russia. The phylogenetic analyses were performed by using sequences of three housekeeping genes (16S rRNA, rpoB and recA) and two accessory genes (nodC and nifH). The results of our multilocus sequence analysis (MLSA) of the three housekeeping genes tree showed that all the 13 isolates belonged to the genus Mesorhizobium and were positioned in six clades. Our concatenated housekeeping gene tree also suggested that the isolates nodulating Astragalus inopinatus, Astragalus frigidus, Astragalus alpinus ssp. alpinus and Oxytropis revoluta might be designated as four new Mesorhizobium species. The 13 isolates were grouped in three clades in the nodC and nifH trees. 15N analysis suggested that the legumes in association with these isolates were actively fixing nitrogen.


Assuntos
Astrágalo/microbiologia , Variação Genética , Mesorhizobium/classificação , Mesorhizobium/isolamento & purificação , Oxytropis/microbiologia , Nodulação , Nódulos Radiculares de Plantas/microbiologia , Regiões Árticas , Proteínas de Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Polimerases Dirigidas por DNA/genética , Mesorhizobium/genética , Tipagem de Sequências Multilocus , N-Acetilglucosaminiltransferases/genética , Oxirredutases/genética , Filogenia , RNA Ribossômico 16S/genética , Recombinases Rec A/genética , Federação Russa , Suécia
9.
Syst Appl Microbiol ; 39(3): 203-210, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26924220

RESUMO

Despite the recognition that Rhizobium leguminosarum sv. viciae is the most common symbiont of Vicia species worldwide, there is no available information on rhizobia nodulating native Vicia species in Sweden. We have therefore studied the genetic diversity and phylogeny of root nodule bacteria isolated from V. cracca, V. hirsuta, V. sepium, V. tetrasperma and V. sylvatica growing in different locations in Sweden as well as an isolate each from V. cracca in Tromsø, Norway, and V. multicaulis in Siberia, Russia. Out of 25 isolates sampled from the six Vicia species in 12 different locations, there were 14 different genotypes based on the atpD, recA and nodA gene phylogenies. All isolates were classified into Rhizobium leguminosarum sv. viciae group based on the concatenated atpD and recA phylogeny and the nodA phylogeny.


Assuntos
Rhizobium leguminosarum/classificação , Rhizobium leguminosarum/isolamento & purificação , Nódulos Radiculares de Plantas/microbiologia , Vicia/microbiologia , Aciltransferases/genética , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Variação Genética/genética , Genótipo , Filogenia , Recombinases Rec A/genética , Rhizobium leguminosarum/genética , Análise de Sequência de DNA , Suécia , Fatores de Transcrição/genética
10.
Rev Environ Health ; 31(1): 145-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26812848

RESUMO

Electrical and electronic waste (e-waste) has become an emerging environmental and human health problem in the world in the 21st century. Recently, the developing nations of West Africa (e.g. Ghana and Nigeria) have become a major destination for e-waste worldwide. In Ghana, the e-waste recyclers use primitive methods (mechanical shredding and open burning) to remove plastic insulation from copper cables. This technique can release highly toxic chemicals and severely affect the environment and human health if improperly managed. It is as a result of the adverse impact on human health that some interventions are being made in Ghana to reduce exposure. The present mode of recycling/dismantling, which happens at Agbogbloshie must be replaced by official receiving/recycling centers to be established. Currently, equipment to strip both large and small cables are available in the country via the Blacksmith Institute (USA) and it is expected that the e-waste workers will embrace the use of these machines. This technology will go a long way to help prevent the burning of e-waste and will be replicated in other smaller e-waste centers in the country.


Assuntos
Países em Desenvolvimento , Resíduo Eletrônico/análise , Saúde Pública/métodos , Gerenciamento de Resíduos/métodos , Gana , Humanos , Saúde Pública/legislação & jurisprudência , Reciclagem , Gerenciamento de Resíduos/legislação & jurisprudência
11.
Ann Glob Health ; 82(5): 700-710, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28283120

RESUMO

BACKGROUND: Exposure to heavy metals at contaminated industrial and mining sites, known also as hot spots, is a significant source of toxic exposure and adverse health outcomes in countries around the world. The Toxic Sites Identification Program (TSIP) developed by Pure Earth, a New York-based nongovernmental organization, is the only systematic effort to catalogue contaminated sites globally. To date, TSIP has identified and catalogued 3282 sites in low- and middle-income countries. The TSIP methodology is not designed to survey all contaminated sites in a country. Rather sites are prioritized based on their perceived impact on human health, and only a limited number of the most highly hazardous sites are surveyed. The total number of contaminated sites globally and the fraction of contaminated sites captured by TSIP is not known. OBJECTIVE: To determine the TSIP site capture rate, the fraction of contaminated sites in a country catalogued by TSIP. METHODS: Ghana was selected for this analysis because it is a rapidly industrializing lower middle income country with a heterogeneous industrial base, a highly urban population (51%), and good public records systems. To develop an estimate of the fraction of sites in Ghana captured by TSIP, assessors targeted randomly selected geographic quadrats for comprehensive assessment using area and population statistics from the Ghana Statistical Service. Investigators physically walked all accessible streets in each quadrat to visually identify all sites. Visual identification was supplemented by field-based confirmation with portable x-ray fluorescence instruments to test soils for metals. To extrapolate from survey findings to develop a range of estimates for the entire country, the investigators used 2 methodologies: a "bottom-up" approach that first estimated the number of waste sites in each region and then summed these regional subtotals to develop a total national estimate; and a "top-down" method that estimated the total number of sites in Ghana and then allocated these sites to each region. Both methods used cluster random sampling principles. FINDINGS: The investigators identified 72 sites in the sampled quadrats. Extrapolating from these findings to the entire country, the first methodology estimated that there are 1561 sites contaminated by heavy metals in Ghana (confidence interval [CI]: 1134-1987), whereas the second estimated 1944 sites (CI: 812-3075). The estimated total number of contaminated sites in Ghana is thus 7-9 times the number of sites captured through TSIP. On a population basis, it was estimated that there are between 31 and 115 contaminated sites per million inhabitants in Ghana. CONCLUSIONS: The findings of this study indicate that the TSIP methodology provides a sound statistical basis for policy formulation. The statistical approaches used in this study can be replicated in other countries to improve estimates of the prevalence of contaminated sites. This information provides important input to calculations of the global burden of disease attributable to hazardous exposures at contaminated sites.


Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/análise , Poluição Ambiental/análise , Substâncias Perigosas , Locais de Resíduos Perigosos/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Poluição Ambiental/estatística & dados numéricos , Gana , Humanos , Indústrias , Prevalência
12.
J Affect Disord ; 197: 125-33, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26991367

RESUMO

BACKGROUND: Little is known about the course of perinatal anxiety, particularly in low and middle income countries. This study aimed at examining trajectories of ante- and postpartum generalized anxiety symptoms in West-African women and their associations with mother and child characteristics. METHODS: 778 women from Côte d'Ivoire and Ghana were investigated between 04/2010 and 03/2014. Anxiety symptoms were measured using the seven-item Generalized Anxiety Disorder scale (GAD-7) at three months antepartum and three, 12 and 24 months postpartum. Growth mixture modeling was applied to identify latent trajectory classes of anxiety. Multinomial logistic regression was used to investigate the associations of psychosocial, sociodemographic, obstetric and clinical characteristics with different trajectories. RESULTS: Four distinct trajectories of anxiety were identified. The majority of women (79.8%) had consistent low anxiety symptoms, while 11.4% had elevated anxiety scores before and around childbirth that decreased gradually. 5.4% of women showed increasing anxiety symptoms over time. Few women (3.3%) had transient anxiety with elevated scores at three and 12 months postpartum. Risk factors for elevated anxiety levels around childbirth were antepartum depressive symptoms, higher levels of stress (economic, marital and social stress), lower child birth weight, and multiparity. Partner support was found to be protective. LIMITATIONS: Anxiety symptoms were assessed using a screening instrument and not through a formal diagnostic classification system. Some putative risk factors were not investigated, and some psychosocial factors were assessed retrospectively. CONCLUSION: The presence of different trajectories underline the importance of monitoring anxiety symptoms in pregnant women and in mothers with infants/toddlers.


Assuntos
Transtornos de Ansiedade/diagnóstico , Ansiedade/psicologia , Depressão Pós-Parto/diagnóstico , Mães/psicologia , Período Pós-Parto/psicologia , Gestantes/psicologia , Estresse Psicológico/psicologia , Adulto , Transtornos de Ansiedade/psicologia , Côte d'Ivoire , Depressão/diagnóstico , Depressão Pós-Parto/psicologia , Feminino , Gana , Humanos , Estudos Longitudinais , Gravidez , Fatores de Risco , Índice de Gravidade de Doença , Estresse Psicológico/etiologia
13.
Mol Plant Microbe Interact ; 18(7): 694-702, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16042015

RESUMO

Genes thuA and thuB in Sinorhizobium meliloti Rm1021 code for a major pathway for trehalose catabolism and are induced by trehalose but not by related structurally similar disaccharides like sucrose or maltose. S. meliloti strains mutated in either of these two genes were severely impaired in their ability to grow on trehalose as the sole source of carbon. ThuA and ThuB show no homology to any known enzymes in trehalose utilization. ThuA has similarity to proteins of unknown function in Mesorhizobium loti, Agrobacterium tumefaciens, and Brucella melitensis, and ThuB possesses homology to dehydrogenases containing the consensus motif AGKHVXCEKP. thuAB genes are expressed in bacteria growing on the root surface and in the infection threads but not in the symbiotic zone of the nodules. Even though thuA and thuB mutants were impaired in competitive colonization of Medicago sativa roots, these strains were more competitive than the wild-type Rml021 in infecting alfalfa roots and forming nitrogen-fixing nodules. Possible reasons for their increased competitiveness are discussed.


Assuntos
Medicago sativa/metabolismo , Medicago sativa/microbiologia , Sinorhizobium meliloti/metabolismo , Trealose/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Transporte Biológico Ativo , DNA Bacteriano/genética , Genes Bacterianos , Teste de Complementação Genética , Dados de Sequência Molecular , Mutação , Raízes de Plantas/microbiologia , Sinorhizobium meliloti/genética , Simbiose
14.
Int J Environ Res Public Health ; 12(10): 13587-601, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26516882

RESUMO

Associations between contaminated land and socio demographics are well documented in high-income countries. In low- and middle-income countries, however, little is known about the extent of contaminated land and possible demographic correlations. This is an important yet sparsely researched topic with potentially significant public health implications as exposure to pollution remains a leading source of morbidity and mortality in low-income countries. In this study, we review the associations between several socio demographic factors (population, population density, unemployment, education, and literacy) and contaminated sites in Ghana. Within this context, both correlation and association intend to show the relationship between two variables, namely contaminated sites and socio demographics. Aggregated district level 2010 census data from Ghana Statistical Service and contaminated site location data from Pure Earth's Toxic Sites Identification Program (TSIP) were spatially evaluated using the number of sites per kilometer squared within districts as the unit of measurement. We found a low to medium positive correlation (ρ range: 0.285 to 0.478) between contaminated sites and the following socio demographics: higher population density, higher unemployment, greater education, and higher literacy rate. These results support previous studies and suggest that several socio demographic factors may be reasonably accurate predictors of contaminated site locations. More research and targeted data collection is needed to better understand these associations with the ultimate goal of developing a predictive model.


Assuntos
Poluição Ambiental/análise , Habitação , Gana , Humanos , Fatores Socioeconômicos
15.
Syst Appl Microbiol ; 34(4): 267-75, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21497473

RESUMO

Very little is known about the genetic diversity and phylogeny of rhizobia nodulating Lotus species in northern temperate regions. We have therefore studied the genetic diversity among a total of 61 root nodule bacteria isolated from Lotus corniculatus and Anthyllis vulneraria from different geographic sites and habitats in Sweden by restriction fragment length polymorphism (RFLP) of the internal transcribed spacer between their 16S rRNA and 23S rRNA (IGS) region. A high diversity consisting of 26 IGS types from 54 L. corniculatus isolates and five IGS types from seven A. vulneraria isolates was found. The 16S rRNA sequences and phylogeny of representatives of the different IGS types showed four interesting exceptions from the majority of the isolates belonging to the genus Mesorhizobium: Two isolates were both found to be closely related to Rhodococcus spp., and two other isolates showed close relationship with Geobacillus spp. and Paenibacillus spp., respectively. The nodA sequences and phylogeny showed that all the isolates, including those not belonging to the traditional rhizobia genera, harbored nodA sequences which were typical of Mesorhizobium loti. Generally, the 16S rRNA and nodA phylogenetic trees were not congruent in that isolates with similar 16S rRNA sequences were associated with isolates harboring different nodA sequences. All the isolates were confirmed to nodulate L. corniculatus in an inoculation test. This is the first report of members of these non-rhizobia genera being able to nodulate legumes, and we suggest that they may have acquired their nodulating properties through lateral gene transfer.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Fabaceae/microbiologia , Variação Genética , Nódulos Radiculares de Plantas/microbiologia , Aciltransferases/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Tipagem Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Suécia
17.
New Phytol ; 179(2): 495-504, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19086182

RESUMO

The role of host and bacterial genotypes in determining the competitiveness of trehalose utilization mutants of Sinorhizobium meliloti and Sinorhizobium medicae was investigated here. Trehalose utilization mutants of S. meliloti and S. medicae were obtained by mutagenesis of their trehalose utilization gene thuB. The mutant strains and the wild type were coinoculated on three cultivars of alfalfa (Medicago sativa) and two cultivars of Medicago truncatula and assessed for competitiveness in root colonization, and nodule occupancy. The thuB mutants formed more nodules than their parent strains on two of the three alfalfa lines tested and on one of the two M. truncatula lines tested. They were not more competitive on the other alfalfa and M. truncatula lines. Their competitiveness for nodule occupancy did not correlate positively with their ability to colonize these roots but correlated with the extent of thuB induction in the infection threads. Induction of thuB was shown to be dependent on the concentration of trehalose in the environment. These results suggest a direct role for host trehalose metabolism in early plant-symbiont interactions and show that the ability to manage host-induced stresses during infection, rather than the ability to colonize the root, is critical for competitive nodulation.


Assuntos
Medicago sativa/genética , Medicago truncatula/genética , Nodulação/fisiologia , Sinorhizobium/metabolismo , Trealose/metabolismo , Relação Dose-Resposta a Droga , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/fisiologia , Genótipo , Medicago sativa/classificação , Medicago sativa/microbiologia , Medicago truncatula/classificação , Medicago truncatula/microbiologia , Concentração Osmolar , Estresse Oxidativo , Sinorhizobium/efeitos dos fármacos , Sinorhizobium/genética , Trealose/farmacologia , beta-Galactosidase/metabolismo
18.
J Pediatr ; 149(5): 676-81, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17095342

RESUMO

OBJECTIVES: To improve algorithms for the identification of children at risk of dying of malaria in endemic areas. STUDY DESIGN: In a prospective study of 2446 children with severe and complicated malaria admitted to a tertiary referral center in Ghana, West Africa, 12 clinical and laboratory signs were evaluated as indicators of death. RESULTS: A prolonged (> 2 seconds) capillary refill time (pCRT) was identified as an independent prognostic indicator of death along with acidosis, coma, and respiratory distress. Among the clinical signs, pCRT increased the risk of dying from 4-fold to 11-fold when present in addition to coma and respiratory distress. CONCLUSIONS: The recognition of pCRT as an independent indicator of death justifies its inclusion as a defining criterion of severe and complicated malaria and improves the use of clinical examinations in the triage of patients with malaria. As pCRT has been shown to reflect circulatory disturbances in children, it should be included in upcoming studies as a possible sign to indicate the need for intravenous fluid administration.


Assuntos
Resistência Capilar , Malária/fisiopatologia , Acidose/mortalidade , Acidose/fisiopatologia , Adolescente , Adulto , Idoso , Análise de Variância , Anemia/mortalidade , Anemia/fisiopatologia , Biomarcadores/sangue , Criança , Pré-Escolar , Coma/mortalidade , Coma/fisiopatologia , Feminino , Gana/epidemiologia , Frequência Cardíaca , Humanos , Malária/mortalidade , Masculino , Pessoa de Meia-Idade , Parasitemia/mortalidade , Parasitemia/fisiopatologia , Prognóstico , Estudos Prospectivos , Insuficiência Respiratória/mortalidade , Insuficiência Respiratória/fisiopatologia , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Taxa de Sobrevida , Fatores de Tempo
19.
World J Microbiol Biotechnol ; 12(5): 531-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24415385

RESUMO

Controlled fermentation of maize was carried out using six strains of Lactobacillus fermentum and one strain of yeast, Saccharomyces cerevisiae, isolated from traditionally fermented maize dough as starter cultures for inoculum enrichement. The fermentations were monitored by pH, acidity, microbiological analysis and taste panel evaluation of two products, kenkey and koko, prepared from the fermented doughs. The strains of L. fermentum used as starter culture dominated the microflora during fermentation and in most inoculated doughs the required pH was attained by 24 h instead of 48 h of dough fermentation. Higher contents of lactic acid bacteria and yeasts were observed in inoculated doughs at the initial stages of fermentation but the spontaneously fermented doughs attained similar lactic acid bacteria and yeasts counts by 24 h of dough fermentation. The organoleptic quality of kenkey and koko prepared from doughs fermented with starter culture for 48 h was not significantly different from the traditional products. Kenkey prepared from doughs fermented for 24 h with starter culture were found to be unacceptable by the taste panel although similarly produced koko was acceptable.

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