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41.
Asare GA Bugyei K Sittie A Yahaya ES Gyan B Adjei S Addo P Wiredu EK Adjei DN Nyarko AK 《Genetics and molecular research : GMR》2012,11(1):100-111
Phyllanthus niruri is a medicinal plant (commonly known as stone breaker) found in the tropics and other parts of the world. It is known for its capacity to block the formation of calcium oxalate crystals and kidney stone formation in urolithiasis. This plant has been used to treat hyperglycemia, hypertension, pain, and mild cases of malaria. We examined the geno-, cyto- and overall toxicity of P. niruri whole plant ethanolic extract. The extract was administered as a single dose of 30 or 300 mg/kg to laboratory rats by gavage, accompanied by negative (0.9% saline) and positive (10 mg/mL N-ethyl-N-nitrosourea) controls that were injected intramuscularly 48 h after extract administration. The ratio of polychromatic (PCE)/normochromatic erythrocytes (NCE) from femur bone marrow was scored for genotoxicity. Cytotoxicity was determined using descending concentrations (0.2-0.0125 g/mL) of the extract incubated with peripheral blood mononuclear cells. Lactate dehydrogenase release from damaged cells was determined and the CC(50) calculated. Subchronic administration of the extract at 30 or 300 mg/kg was done for 90 days to determine general toxicity. PCE:NCE (%) for the extract and negative control was 63, compared to 168 (positive control). The CC(50) was 26.3 mg/mL and hepato-renal toxicity after subchronic extract administration was nil. We conclude that ethanol extract of P. niruri is not cytotoxic or genotoxic, and is generally non-toxic on subchronic administration. 相似文献
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Samuel Adjei Akira Sato Takahiro Nagase Kazumi Matsubara Yoichi Matsuda Takao Namikawa Akira Ishikawa 《Experimental Animals》2008,57(2):129-134
A genetic linkage map for Suncus murinus was previously constructed with 11 marker loci. In this study, we developed 172 new microsatellite and three RFLP markers, and re-constructed a new framework map by combining all markers. The new map comprises 42 markers that are distributed into 12 linkage groups, two of which are assigned to chromosomes, and spans 403.5 cM with an average inter-marker distance of 13.5 cM. 相似文献
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Schreiber N Khattab A Petter M Marks F Adjei S Kobbe R May J Klinkert MQ 《Parasitology》2008,135(2):155-167
Clinical immunity to Plasmodium falciparum malaria develops after repeated exposure to the parasite. At least 2 P. falciparum variant antigens encoded by multicopy gene families (var and rif) are targets of this adaptive antibody-mediated immunity. A third multigene family of variant antigens comprises the stevor genes. Here, 4 different stevor sequences were selected for cloning and expression in Escherichia coli and His6-tagged fusion proteins were used for assessing the development of immunity. In a cross-sectional analysis of clinically immune adults living in a malaria endemic area in Ghana, high levels of anti-STEVOR IgG antibody titres were determined in ELISA. A cross-sectional study of 90 nine-month-old Ghanaian infants using 1 recombinant STEVOR showed that the antibody responses correlated positively with the number of parasitaemia episodes. In a longitudinal investigation of 17 immunologically na?ve 9-month-old infants, 3 different patterns of anti-STEVOR antibody responses could be distinguished (high, transient and low). Children with high anti-STEVOR-antibody levels exhibited an elevated risk for developing parasitaemia episodes. Overall, a protective effect could not be attributed to antibodies against the STEVOR proteins chosen for the study presented here. 相似文献
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A polyomic approach to elucidate the fluoranthene-degradative pathway in Mycobacterium vanbaalenii PYR-1
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Kweon O Kim SJ Jones RC Freeman JP Adjei MD Edmondson RD Cerniglia CE 《Journal of bacteriology》2007,189(13):4635-4647
Mycobacterium vanbaalenii PYR-1 is capable of degrading a wide range of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs), including fluoranthene. We used a combination of metabolomic, genomic, and proteomic technologies to investigate fluoranthene degradation in this strain. Thirty-seven fluoranthene metabolites including potential isomers were isolated from the culture medium and analyzed by high-performance liquid chromatography, gas chromatography-mass spectrometry, and UV-visible absorption. Total proteins were separated by one-dimensional gel and analyzed by liquid chromatography-tandem mass spectrometry in conjunction with the M. vanbaalenii PYR-1 genome sequence (http://jgi.doe.gov), which resulted in the identification of 1,122 proteins. Among them, 53 enzymes were determined to be likely involved in fluoranthene degradation. We integrated the metabolic information with the genomic and proteomic results and proposed pathways for the degradation of fluoranthene. According to our hypothesis, the oxidation of fluoranthene is initiated by dioxygenation at the C-1,2, C-2,3, and C-7,8 positions. The C-1,2 and C-2,3 dioxygenation routes degrade fluoranthene via fluorene-type metabolites, whereas the C-7,8 routes oxidize fluoranthene via acenaphthylene-type metabolites. The major site of dioxygenation is the C-2,3 dioxygenation route, which consists of 18 enzymatic steps via 9-fluorenone-1-carboxylic acid and phthalate with the initial ring-hydroxylating oxygenase, NidA3B3, oxidizing fluoranthene to fluoranthene cis-2,3-dihydrodiol. Nonspecific monooxygenation of fluoranthene with subsequent O methylation of dihydroxyfluoranthene also occurs as a detoxification reaction. 相似文献
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Richard Odame Phillips Delphin Mavinga Phanzu Marcus Beissner Kossi Badziklou Elysée Kalundieko Luzolo Fred Stephen Sarfo Wemboo Afiwa Halatoko Yaw Amoako Michael Frimpong Abass Mohammed Kabiru Ebekalisai Piten Issaka Maman Bawimodom Bidjada Adjaho Koba Koffi Somenou Awoussi Basile Kobara J?rg Nitschke Franz Xaver Wiedemann Abiba Banla Kere Ohene Adjei Thomas L?scher Bernhard Fleischer Gisela Bretzel Karl-Heinz Herbinger 《PLoS neglected tropical diseases》2015,9(1)
Background
The only available vaccine that could be potentially beneficial against mycobacterial diseases contains live attenuated bovine tuberculosis bacillus (Mycobacterium bovis) also called Bacillus Calmette-Guérin (BCG). Even though the BCG vaccine is still widely used, results on its effectiveness in preventing mycobacterial diseases are partially contradictory, especially regarding Buruli Ulcer Disease (BUD). The aim of this case-control study is to evaluate the possible protective effect of BCG vaccination on BUD.Methodology
The present study was performed in three different countries and sites where BUD is endemic: in the Democratic Republic of the Congo, Ghana, and Togo from 2010 through 2013. The large study population was comprised of 401 cases with laboratory confirmed BUD and 826 controls, mostly family members or neighbors.Principal Findings
After stratification by the three countries, two sexes and four age groups, no significant correlation was found between the presence of BCG scar and BUD status of individuals. Multivariate analysis has shown that the independent variables country (p = 0.31), sex (p = 0.24), age (p = 0.96), and presence of a BCG scar (p = 0.07) did not significantly influence the development of BUD category I or category II/III. Furthermore, the status of BCG vaccination was also not significantly related to duration of BUD or time to healing of lesions.Conclusions
In our study, we did not observe significant evidence of a protective effect of routine BCG vaccination on the risk of developing either BUD or severe forms of BUD. Since accurate data on BCG strains used in these three countries were not available, no final conclusion can be drawn on the effectiveness of BCG strain in protecting against BUD. As has been suggested for tuberculosis and leprosy, well-designed prospective studies on different existing BCG vaccine strains are needed also for BUD. 相似文献47.
Arantza Me?aca Harry Tagbor Rose Adjei Constance Bart-Plange Yvette Collymore Antoinette Ba-Nguz Kelsey Mertes Allison Bingham 《PloS one》2014,9(10)
Malaria is a leading cause of morbidity and mortality among children in Ghana. As part of the effort to inform local and national decision-making in preparation for possible malaria vaccine introduction, this qualitative study explored community-level factors that could affect vaccine acceptance in Ghana and provides recommendations for a health communications strategy. The study was conducted in two purposively selected districts: the Ashanti and Upper East Regions. A total of 25 focus group discussions, 107 in-depth interviews, and 21 semi-structured observations at Child Welfare Clinics were conducted. Malaria was acknowledged to be one of the most common health problems among children. While mosquitoes were linked to the cause and bed nets were considered to be the main preventive method, participants acknowledged that no single measure prevented malaria. The communities highly valued vaccines and cited vaccination as the main motivation for taking children to Child Welfare Clinics. Nevertheless, knowledge of specific vaccines and what they do was limited. While communities accepted the idea of minor vaccine side effects, other side effects perceived to be more serious could deter families from taking children for vaccination, especially during vaccination campaigns. Attendance at Child Welfare Clinics after age nine months was limited. Observations at clinics revealed that while two different opportunities for counseling were offered, little attention was given to addressing mothers’ specific concerns and to answering questions related to child immunization. Positive community attitudes toward vaccines and the understanding that malaria prevention requires a comprehensive approach would support the introduction of a malaria vaccine. These attitudes are bolstered by a well-established child welfare program and the availability in Ghana of active, flexible structures for conveying health information to communities. At the same time, it would be important to improve the quality of Child Welfare Clinic services, particularly in relation to communication around vaccination. 相似文献
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Debrah AY Mand S Specht S Marfo-Debrekyei Y Batsa L Pfarr K Larbi J Lawson B Taylor M Adjei O Hoerauf A 《PLoS pathogens》2006,2(9):e92
Lymphatic filariasis is a disease of considerable socioeconomic burden in the tropics. Presently used antifilarial drugs are able to strongly reduce transmission and will thus ultimately lower the burden of morbidity associated with the infection, however, a chemotherapeutic principle that directly induces a halt or improvement in the progression of the morbidity in already infected individuals would constitute a major lead. In search of such a more-effective drug to complement the existing ones, in an area endemic for bancroftian filariasis in Ghana, 33 microfilaremic and 18 lymphedema patients took part in a double-blind, placebo-controlled trial of a 6-wk regimen of 200 mg/day doxycycline. Four months after doxycycline treatment, all patients received 150-200 microg/kg ivermectin and 400 mg albendazole. Patients were monitored for Wolbachia and microfilaria loads, antigenemia, filarial dance sign (FDS), dilation of supratesticular lymphatic vessels, and plasma levels of lymphangiogenic factors (vascular endothelial growth factor-C [VEGF-C] and soluble vascular endothelial growth factor receptor-3 [(s)VEGFR-3]). Lymphedema patients were additionally monitored for stage (grade) of lymphedema and the circumferences of affected legs. Wolbachia load, microfilaremia, antigenemia, and frequency of FDS were significantly reduced in microfilaremic patients up to 24 mo in the doxycycline group compared to the placebo group. The mean dilation of supratesticular lymphatic vessels in doxycycline-treated patients was reduced significantly at 24 mo, whereas there was no improvement in the placebo group. Preceding clinical improvement, at 12 mo, the mean plasma levels of VEGF-C and sVEGFR-3 decreased significantly in the doxycycline-treated patients to a level close to that of endemic normal values, whereas there was no significant reduction in the placebo patients. The extent of disease in lymphedema patients significantly improved following doxycycline, with the mean stage of lymphedema in the doxycycline-treated patients being significantly lower compared to placebo patients 12 mo after treatment. The reduction in the stages manifested as better skin texture, a reduction of deep folds, and fewer deep skin folds. In conclusion, a 6-wk regimen of antifilarial treatment with doxycycline against W. bancrofti showed a strong macrofilaricidal activity and reduction in plasma levels of VEGF-C/sVEGFR-3, the latter being associated with amelioration of supratesticular dilated lymphatic vessels and with an improvement of pathology in lymphatic filariasis patients. 相似文献
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This research provides a new way to measure error in microarray data in order to improve gene expression analysis.Microarray data contains many sources of error.In order to glean information about mRNA expression levels,the true signal must first be segregated from noise.This research focuses on the variation that can be captured at the spot level in cDNA microarray images.Variation at other levels,due to differences at the array,dye,and block levels,can be corrected for by a variety of existing normalizati... 相似文献