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Browsing by Author "et. al"

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Ab initio investigation of O2 adsorption on Ca-doped LaMnO3 cathodes in solid oxide fuel cells
(Royal Society of Chemistry, 2018) Aniagyei, Albert; Dzade, Nelson Y.; Tia, Richard; Adei, Evans; Catlow, C. R. A.; et. al
We present a Hubbard-corrected density functional theory (DFT+U) study of the adsorption and reduction reactions of oxygen on the pure and 25% Ca-doped LaMnO3 (LCM25) {100} and {110} surfaces. The effect of oxygen vacancies on the adsorption characteristics and energetics has also been investigated. Our results show that the O2 adsorption/reduction process occurs through the formation of superoxide and peroxide intermediates, with the Mn sites found to be generally more active than the La sites. The LCM25{110} surface is found to be more efficient for O2 reduction than the LCM25{100} surface due to its stronger adsorption of O2, with the superoxide and peroxide intermediates shown to be energetically more favorable at the Mn sites than at the Ca sites. Moreover, oxygen vacancy defect sites on both the {100} and{110} surfaces are shown to be more efficient for O2 reduction, as reflected in the higher adsorption energies calculated on the defective surfaces compared to the perfect surfaces. We show from Lowdin population analysis that the O 2 adsorption on the pure and 25% Ca-doped ̈ LaMnO3 surfaces is characterized by charge transfer from the interacting surface species into the adsorbed oxygen pg orbital, which results in weakening of the O–O bonds and its subsequent reduction. The elongated O–O bonds were confirmed via vibrational frequency analysis.
Antibody screening tests variably overestimate the prevalence of hepatitis C virus infection among HIV-infected adults in Ghana
(John Wiley & Sons Ltd, 2014) King, S.; Adjei-Asante, K.; Appiah, L.; Adinku, D.; Phillips, Richard Odame; et. al
HIV coinfection with HCV has been poorly studied in sub-Saharan Africa, and the reliability of available seroprevalence estimates remains uncertain. The study aim was to determine HCV RNA prevalence in HIV-infected subjects receiving care in Kumasi, Ghana, and relate the findings to HCV antibody detection. From a population of 1520 HIV-infected adults, all HBsAg-positive subjects (n = 236) and a random subset of HBsAg-negative subject (n = 172) were screened for HCV RNA using pooled plasma; positive samples were genotyped by core and NS5B sequencing. HCV antibodies were detected by three commercial screening assays and confirmed by the line immunoassay. HCV RNA was detected in 4/408 subjects (1.0%, 95% confidence interval 0.0–1.9%), comprising 3/ 236 (1.3%; 0.0–2.8%) HBsAg-positive and 1/172 (0.6%; 0.0–1.8%) HBsAg-negative subjects. HCV RNA-positive subjects showed reactivity in all three antibody screening assays. Among HCV RNA-negative subjects, 5/67 (7.5%), 5/67 (7.5%) and 19/67 (28.4%) showed antibody reactivity by each screening assay, respectively, including two (3.0%) with reactivity by all three assays. Only one sample (1.5%) had confirmed antibody reactivity by line immunoassay indicating past HCV infection. HCV-positive subjects (three males, two females) were aged 30–46 years, by questionnaire-based interview reported surgical procedures and blood transfusion as risk factors for infection. HCV genotypes were 2 (subtypes 2j, 2l, 2k/unassigned) and 1 (subtype unassigned). Without further testing, HCV antibody screening assays variably overestimated HCV prevalence among HIV-infected subjects in Ghana. These findings inform the interpretation of previous seroprevalence estimates based upon screening assays alone.
Buruli ulcer treatment: Rate of surgical intervention differs highly between treatment centers in West Africa
(PLOS Neglected Tropical Diseases, 2019-10-28) Phillips, Richard Odame; Wadagni, Anita C.; Steinhorst, Jonathan; Barogui, Yves T.; Catraye, P. M.; et. al
Background Antibiotic treatment proved itself as the mainstay of treatment for Buruli ulcer disease. This neglected tropical disease is caused by Mycobacterium ulcerans. Surgery persists as an adjunct therapy intended to reduce the mycobacterial load. In an earlier clinical trial, patients benefited from delaying the decision to operate. Nevertheless, the rate of surgical interventions differs highly per clinic. Methods A retrospective study was conducted in six different Buruli ulcer (BU) treatment centers in Benin and Ghana. BU patients clinically diagnosed between January 2012 and December 2016 were included and surgical interventions during the follow-up period, at least one year after diagnosis, were recorded. Logistic regression analysis was carried out to estimate the effect of the treatment center on the decision to perform surgery, while controlling for interaction and confounders. Results A total of 1193 patients, 612 from Benin and 581 from Ghana, were included. In Benin, lesions were most frequently (42%) categorized as the most severe lesions (WHO criteria, category III), whereas in Ghana lesions were most frequently (44%) categorized as small lesions (WHO criteria, category I). In total 344 (29%) patients received surgical intervention. The percentage of patients receiving surgical intervention varied between hospitals from 1.5% to 72%. Patients treated in one of the centers in Benin were much more likely to have surgery compared to the clinic in Ghana with the lowest rate of surgical intervention (RR =46.7 CI 95% [17.5–124.8]). Even after adjusting for confounders (severity of disease, age, sex, limitation of movement at joint at time of diagnosis, ulcer and critical sites), rates of surgical interventions varied highly. Conclusion The decision to perform surgery to reduce the mycobacterial load in BU varies highly per clinic. Evidence based guidelines are needed to guide the role of surgery in the treatment of BU
CD27 expression of T-cells discriminates IGRA-negative TB patients from healthy contacts in Ghana
(Elsevier Masson SAS, 2019) Phillips, Richard Odame; Adankwah, Ernest; Güler, Alptekin; Mayatepek, Ertan; Nausch, Norman; et. al
IFN-g release assays (IGRAs) have suboptimal sensitivity for detection of Mycobacterium tuberculosis (Mtb) infection and cannot discriminate between tuberculosis (TB) patients and healthy -potentially Mtb infected- contacts (HCs). In a case-control study, we determined T-cell phenotypes of IGRAs in TB patients (n ¼ 20) and HCs (n ¼ 20) from Ghana. CD27 expression of T-cells was significantly lower in TB patients as compared to HCs independent from Mtb-specificity. CD27 expression discriminated both study groups - including TB patients with low or indeterminate IGRA results - effectively. We conclude that CD27 is a promising biomarker for diagnosis of TB patients with inconclusive IGRA results.
Characterization, Spatial Variation and Risk Assessment of Heavy Metals and a Metalloid in Surface Soils in Obuasi, Ghana
(Black Smith Institute, 2018-08) Akoto, Osei; Bortey-Sam, Nesta; Nakayama, Shouta M.M.; Ikenaka, Yoshinori; Baidoo, Elvis; et. al
Soil contamination with heavy metals and metalloids has become an increasingly important issue in recent years. Objectives. The present study examines possible contamination of the environment with metals from gold mining activities in Obuasi, Ghana. Methods. Soil samples were collected from commercial and residential areas and tailing dams in Obuasi in order to investigate the extent of lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu), zinc (Zn), cobalt (Co), chromium (Cr), nickel (Ni) and arsenic (As) pollution, create thematic maps showing the extent of heavy metals pollution, identify the sources of pollution, and to assess risks to humans and the surrounding ecological system. Results. Mean concentrations of metals from the study were found in the order of As > Cu > Zn > Cr > Ni > Pb > Co > Hg > Cd. The results showed that all communities were severely polluted with As, and distribution maps highlighted two hot spots at the sulfite treatment plant and Pompura treatment plant tailings dams. Additionally, the levels of Pb, Cu and Zn were elevated around the city center where vehicular traffic is very dense. Principal component analysis indicated that mining activities may have significantly contributed to metal levels in Obuasi soils. The potential ecological risk (RI) indicated that soils in 41% of the communities pose very high risks to the surrounding ecological system, 50% pose considerable risk, and 9% pose a moderate risk. Arsenic and Hg contributed 73 and 15% of the RI, respectively. The average hazard quotient due to soil As exposure was 2.51 ± 1.23 and ingestion of soils in 95% of the communities in the study area could pose non-carcinogenic health risks to children. Moreover, the average cancer risk for children from the communities was 1.13 × 10-3. Based on the United States Environmental Protection Agency (USEPA) recommendation for cancer risk of 10-6 to 10-4, the cancer risk for children (> 10-3) was higher in 45% of the studied communities. Conclusions. The central part of the study area is polluted with Pb, Zn and Cu, and As pollution is severe in all of the studied communities. The RI from all study sites revealed very high risk to the ecological system, including mammals. There could be non-cancer and cancer risks to Obuasi residents due to ingestion of As-contaminated soils, and children are particularly vulnerable. Competing Interests. The author declares no competing financial interests
CLIMATE VARIABILITY AND MALARIA INCIDENCE IN PERI-URBAN, URBAN AND RURAL COMMUNITIES AROUND KUMASI, GHANA: A CASE STUDY AT THREE HEALTH FACILITIES; EMENA, ATONSU AND AKROPONG
(Bioinfo Publications, 2012-01-01) Tay, S.C.k.; Danuor, S.K.; Mensah, D.C.; Acheampong, G.; Badu, K.; et. al
Background: Changes in temperature, rainfall and relative humidity due to climate change are expected to directly influence malaria transmission dynamics, by modifying the behavior and geographical distribution of malaria vectors while shortening the sporogonic cycle of the parasite in the vector. These changes will have varying effects on malaria incidence in different eco-epidemiological settings. The aim was to examine the impact of climate variability on malaria incidence in three micro-epidemiological ecosystems in the forest zone of Ghana, Ashanti Region. Methods: Data on climatic variables (rainfall, temperature and humidity) from January 2008 to- October 2009 were obtained from the two weather stations. Hospital based confirmed malaria incidence data were obtained for the same period from Akropong (rural) hospital whereas malaria incidence data were obtained from January 2008-June 2009 and January 2008-August 2009 for Emena (peri-urban) and Atonsu (urban) hospitals respectively. Microscopy was used to identify the predominant Plasmodium species. Spearman’s correla-tion analysis and cross correlation analysis that allowed a time-lag of 0-3 month were performed to examine the role of climatic variables on malaria incidence. Results: There was a direct correlation between monthly malaria incidence and monthly climatic variables at different time-lags and location. At every study site, different climatic variables were seen to play different roles on the occurrence of malaria. At Akropong and Emena, the study indicates that rainfall and minimum temperature are the major drivers of malaria incidence though this relationship was significant at different time-lags in different eco-epidemiological settings. At Atonsu, the study indicates that rainfall and maximum tem-perature are the major contributors to malaria incidence. Conclusion: Climatic variables have direct and indirect influence on malaria incidence and these variables can predict malaria inci-dence and be suited for forecasting the malaria occurrence in areas with similar ecological features in the Ashanti Region of Ghana.
Combined Inflammatory and Metabolic Defects Reflected by Reduced Serum Protein Levels in Patients with Buruli Ulcer Disease
(PLOS Neglected Tropical Diseases, 2014-04-10) Phillips, Richard Odame; Sarfo, Fred Stephen; Landier, Jordi; Oldenburg, Reid; Frimpong, Michael; et. al
Buruli ulcer is a skin disease caused by Mycobacterium ulcerans that is spreading in tropical countries, with major public health and economic implications in West Africa. Multi-analyte profiling of serum proteins in patients and endemic controls revealed that Buruli ulcer disease down-regulates the circulating levels of a large array of inflammatory mediators, without impacting on the leukocyte composition of peripheral blood. Notably, several proteins contributing to acute phase reaction, lipid metabolism, coagulation and tissue remodelling were also impacted. Their down-regulation was selective and persisted after the elimination of bacteria with antibiotic therapy. It involved proteins with various functions and origins, suggesting that M. ulcerans infection causes global and chronic defects in the host’s protein metabolism. Accordingly, patients had reduced levels of total serum proteins and blood urea, in the absence of signs of malnutrition, or functional failure of liver or kidney. Interestingly, slow healers had deeper metabolic and coagulation defects at the start of antibiotic therapy. In addition to providing novel insight into Buruli ulcer pathogenesis, our study therefore identifies a unique proteomic signature for this disease.
A comparative studyof the interactionof nickel, titanium,palladium, andgold metalswith single-walled carbonnanotubes:A DFT approach
(Elsevier B.V., 2019-02-20) Kayang, K.W.; Nyankson, E.; Efavi, J.K.; Apalangya, V.A.; Tia, Richard; et. al
Interactions between transition metal atoms, nickel, titanium, palladium and gold and (3,3), (4,2), (6,0) and(5,1) carbon nanotubes were studied using first principles calculations. The Fermi energy levels of the carbonnanotubesstudiedwerefoundtoincreaseduringinteractionswiththetransitionmetalatoms.Amongstthefourmetals, gold atom was found to have an enhanced interaction with the nanotubes transforming from semi-conductingtoaconductingtube.Titaniumwasalsofoundtoshowsimilarcharacteristicstogoldonlywhentheatomwasplacedinthemiddleofthecarbonnanotubes.Nickelandpalladiumatomsinteractionsdidnotaffectmuchtheelectronicpropertiesofthecarbonnanotubes,withsomeslightchangesintheelectronicpropertiesatsomespecificsitesofthenanotubes.Itisproposedfromthisstudythat,thecarbonnanotube-metalinteractionscould be used as a guide to shed light on the electronic properties of such materials which could become pro-mising engineering materialsand revolutionizethe electronic industry.
Comparison of Two Assays for Molecular Determination of Rifampin Resistance in Clinical Samples from Patients with Buruli Ulcer Disease
(Journal of Clinical Microbiology, 2014-01-29) Phillips, Richard Odame; Jansson, Moritz; Beissner, Marcus; Badziklou, Kossi; Piten, Ebekalisai; et. al
Buruli ulcer disease (BUD), caused by Mycobacterium ulcerans, involves the skin, subcutaneous fatty tissue, and bones and predominantly affects children 15 years of age. If left untreated, contractures may cause severe functional limitation. Standardized antimycobacterial treatment consists of rifampin (RMP) and streptomycin administered for 8 weeks. An oral regimen combiningRMPand clarithromycin is currently under clinical evaluation (1–3). Notwithstanding the efficiency of chemotherapy, treatment failures and various types of secondary lesions have been reported, suggesting the need for customized clinical management strategies (4–6).
Contamination Levels and Sources of Heavy Metals and a Metalloid in Surface Soils in the Kumasi Metropolis, Ghana
(Black Smith Institute, 2017-09) Akoto, Osei; Bortey-Sam, Nesta; Ikenaka, Yoshinori; Nakayama, Shouta M.M.; Baidoo, Elvis; et. al
Environmental contamination with heavy metals and metalloids due to industrial, smelting and mining activities have become common in large and growing cities. Kumasi is one of the most industrialized cities in Ghana and experiences metal pollution due to recent and past activities. Although metals are naturally abundant in the area, their accumulation in soils could potentially lead to adverse effects on local ecosystems. Objectives. The aims of this study were to determine the distribution, enrichment, geo-accumulation and sources of metals in Kumasi soils and to estimate the contamination factor (CF) and pollution load index (PLI) of these metals in soils. Methods. Concentrations of eight heavy metals and a metalloid were determined in 112 soil samples randomly collected from 31 sampling sites in the area. In addition, 5 soil samples were collected from a pristine site (Kwame Nkrumah University of Science and Technology Botanical Gardens) for data comparison, to determine the local background values for metal concentrations and to evaluate the extent of metal pollution in the study area. Results. Heavy metals such as zinc (Zn), lead (Pb), cadmium (Cd) and chromium (Cr) were enriched in 65, 32, 58 and 93% of the sampling sites, respectively, and geo-accumulation indexes for Cr, Zn, Cd, mercury (Hg) and Pb showed moderate to extreme contamination in 100, 97, 77, 65 and 45% of the sampling sites, respectively. Principal component and cluster analyses revealed that industrial activities including mining were the major sources of metals in Kumasi soils with high metal input in the community of Suame. Distribution maps revealed hotspots of Cd, nickel (Ni), arsenic (As), cobalt (Co), copper (Cu) and Pb in Suame. The highest CFs for Cu, Cd, Ni, As, Co and Pb highlighted anthropogenic inputs in Suame, while Hg was highest in Mbrom, Zn in Suntreso, and Cr in Aboabo. Conclusions. The PLI of metals revealed Suame as the most polluted study site, while Anomangye and Bomso were the least polluted. Competing Interests. The authors declare no competing financial interests.
Detection of Mycolactone A/B in Mycobacterium ulcerans–Infected Human Tissue
(PLoS Neglected Tropical Diseases, 2010-01-05) Sarfo, Fred Stephen; Phillips, Richard Odame; Rangers, Brian; Mahrous, Engy A.; Lee, Richard E.; et. al
Background: Mycobacterium ulcerans disease (Buruli ulcer) is a neglected tropical disease common amongst children in rural West Africa. Animal experiments have shown that tissue destruction is caused by a toxin called mycolactone. Methodology/Principal Findings: A molecule was identified among acetone-soluble lipid extracts from M. ulcerans (Mu)- infected human lesions with chemical and biological properties of mycolactone A/B. On thin layer chromatography this molecule had a retention factor value of 0.23, MS analyses showed it had an m/z of 765.6 [M+Na+] and on MS:MS fragmented to produce the core lactone ring with m/z of 429.4 and the polyketide side chain of mycolactone A/B with m/z of 359.2. Acetone-soluble lipids from lesions demonstrated significant cytotoxic, pro-apoptotic and anti-inflammatory activities on cultured fibroblast and macrophage cell lines. Mycolactone A/B was detected in all of 10 tissue samples from patients with ulcerative and pre-ulcerative Mu disease. Conclusions/Significance: Mycolactone can be detected in human tissue infected with Mu. This could have important implications for successful management of Mu infection by antibiotic treatment but further studies are needed to measure its concentration.
Detection of Viable Mycobacterium ulcerans in Clinical Samples by a Novel Combined 16S rRNA Reverse Transcriptase/IS2404 Real-Time qPCR Assay
(PLOS Neglected Tropical Diseases, 2012-08-28) Phillips, Richard Odame; Beissner, Marcus; Symank, Dominik; Amoako, Yaw Ampem; Awua-Boateng, Nana- Yaa; et. al
Buruli ulcer disease (BUD) caused by Mycobacterium ulcerans involves the skin and soft tissue. If left untreated, extensive destruction of tissue followed by scarring and contractures may lead to severe functional limitations. Following the introduction of standardized antimycobacterial chemotherapy with rifampicin and streptomycin, recurrence rates of less than 2% were reported. However, treatment failures occur and a variety of secondary lesions necessitating customized clinical management strategies have been reported. True recurrences by definition occur more than three months after completion of antibiotic treatment, are characterised by the presence of viable bacilli, and require a second course of antibiotics. ‘‘Non-healers’’ may harbour viable, possibly drug-resistant M. ulcerans strains and may benefit from surgical intervention. Early-onset immune-mediated paradoxical reactions emerging during or shortly after treatment do not contain viable bacilli and may heal under conventional wound care and/or minor surgery; lateonset secondary lesions presumably attributable to secondary infection foci may clear spontaneously through enhanced immune responses primed by initial treatment. None of the current diagnostic techniques is applicable to rapidly address the pivotal question of the presence of viable bacilli in non-healers and patients with secondary BUD lesions, and optimal time points for collection of follow-up samples have not yet been investigated. Therefore, to date treatment monitoring is mainly based on clinical observation [1– 5]. Reverse transcriptase assays targeting 16S rRNA and mRNA were successfully applied for the rapid detection of viable mycobacteria in clinical samples from patients with tuberculosis and leprosy [6,7]. To employ this technique for classification of BUD lesions and monitoring of treatment success we developed a M. ulcerans–specific RNA-based viability assay combining a 16S rRNA reverse transcriptase real-time PCR (RT-qPCR) to determine bacterial viability with an IS2404 quantitative real-time PCR (qPCR) for increased specificity and simultaneous quantification of bacilli.
Distribution of Heavy Metals in Organs of Sheep and Goat Reared in Obuasi: A Gold Mining Town in Ghana
(International Journal of Environmental Science and Toxicology, 2014) Akoto, Osei; Bortey-Sam, Nesta; Nakayama, Shouta M.M.; Ikenaka, Yoshinori; Elvis Baidoo; et. al
The aim of this study was to determine the concentration of metals in some organs of goat and sheep and assess the distribution of these metals in the sample tissues. Samples were digested with 60% nitric acid and concentrations of the heavy metals measured using atomic absorption spectrophotometer while the concentrations of Hg were measured with mercury analyzer. Concentrations of Zn, Cu were very high in the organs followed by Cr, Ni, Co, Pb, Cd, As and Hg. Total rank score assessment showed that liver, kidney and lung had accumulated high levels of metals while brain accumulated lowest. Mean Zn concentrations in all organs ranged between 24.88±11.22 in goat brain and 97.06±19.66 mg/kg in liver of goat. Mean Cu concentrations ranged between 7.96±1.20 (small intestine of sheep) and 106.63±111.24 mg/kg in liver of sheep. Cd concentration in liver and kidney in both species were above the EU set limit of 0.05 mg/kg. Concentrations of Co in liver, kidney and lungs of the two different animals did not vary significantly. As and Hg concentration were homogenous in all the organs of both animals and did not show any significant variation. Prolonged consumption of kidney, liver and lungs of goats and sheep having high concentrations of Zn Cu and Cd may lead to accumulation of these metals in humans and cause metal toxicity.
Excretion of polycyclic aromatic hydrocarbon metabolites (OH-PAHs) in cattle urine in Ghana
(Elsevier, 2016-11-01) Bortey-Sam, Nesta; Ikenaka, Yoshinori; Akoto, Osei; Nakayama, Shouta M.M.; Marfo, Jemima; et. al
Previous studies of polycyclic aromatic hydrocarbons (PAHs) in particulate matter, soils and livers of wild rats indicated that the city centre of Kumasi, Ghana has been severely polluted with high cancer potency. Cattle urine were therefore collected from Kumasi (urban) and Offinso (rural), Ghana: to determine concentrations of urinary PAH metabolites (OH-PAHs); and find their association with sex; and to estimate exposure of cattle to PAHs from the different sites. From the results, geometric mean concentrations (adjusted by specific gravity), GMSG, showed that 2-OHNaphthalene (2-OHNap) was the most abundant OH-PAH in cattle urine from all study sites, and naphthalene-containing-mothballs might have contributed significantly to the levels. There was no significant difference between urinary OH-PAHs concentrations in cattle from urban and rural sites except for 2-OHPhe and 4-OHPhe, and similar to urban areas, rural sites could also be polluted with PAHs. GMSG of 2-OHNap in cattle urine in Kokote (21.9 ± 6.51 ng/mL; a rural area), was significantly higher compared to the other sites followed by Oforikrom (4.15 ± 4.37 ng/mL; urban). The GMSG concentration (ng/mL) of the sum of OH-PAHs decreased in the order, Kokote (44.7) > Oforikrom (7.87) > Saboa (6.98) > Santasi (6.68) > and Twumasen Estate (5.23). The high concentrations of urinary 2-OHNap, 2-3-OHFlu, 2-OHPhe, 3-OHPhe and 4-OHPhe in Kokote indicated high PAHs exposure to cattle in this area or different/specific source of PAHs exposure. GMSG of 2-OHNap was significantly higher in male cattle compared to females while 1-9-OHPhe was significantly higher in females. Capsule: 3 PAH metabolites were measured in cattle urine in urban and rural areas in Ghana; 2- OHNaphthalene (2-OHNap) was the most abundant PAH metabolites.
Exposure levels of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in wild rats in Kumasi, Ghana
(Peer reviewed and revised papers, 2015-08-31) Bortey-Sam, Nesta; Ikenaka, Yoshinori; Akoto, Osei; Nakayama, Shouta M.M.; Yohannes, Yared Beyene; et. al
Wild rats were trapped from communities in Kumasi, Ghana, to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and heavy metals. The results of the study showed that phenanthrene (0.51 ± 0.08 ng/g dw) was the most abundant individual PAH in the liver of wild rats. The ΣPAH concentrations in liver ranged from 0.05 to 1.64 ng/g dw in Bomso (a community) and city centre, respectively. Abundance of individual PAHs in the liver of wild rats decreased in the order: phenanthrene > pyrene > acenaphthene > naphthalene > fluoranthene and > anthracene. Levels of phenanthrene and pyrene detected were significantly higher than other PAHs. Naphthalene and fluoranthene were detected in 80% and 78% of the samples collected respectively. Heavy metals in the liver of wild rats in Kumasi decreased in the order Zn > Cu > As > Ni > Pb > Co > Cd > Cr.
Former Buruli Ulcer Patients' Experiences and Wishes May Serve as a Guide to Further Improve Buruli Ulcer Management
(PLOS Neglected Tropical Diseases, 2016-12-29) Phillips, Richard Odame; Velink, Anita; Woolley, Rebecca J.; Abass, Kabiru M.; Agumah, Emmanuel; et. al
Background Buruli ulcer (BU), caused by Mycobacterium ulcerans, is a neglected tropical disease frequently leading to permanent disabilities. The ulcers are treated with rifampicin and streptomycin, wound care and, if necessary surgical intervention. Professionals have exclusively shaped the research agenda concerning management and control, while patients' perspective on priorities and preferences have not explicitly been explored or addressed. Methodology/Principal findings To get insight into patient perception of the management and control of Buruli ulcer a mixed methods research design was applied with a questionnaire and focus group discussions among former BU patients. Data collection was obtained in collaboration with a local team of native speakers in Ghana. A questionnaire was completed by 60 former patients and four focus group discussions were conducted with eight participants per group. Former patients positively evaluated both the effectiveness of the treatment and the financial contribution received for the travel costs to the hospitals. Pain experienced during treatment procedures, in particular wound care and the streptomycin injections, and the side-effects of the treatment were negatively evaluated. Former patients considered the development of preventive measures and knowledge on the transmission as priorities. Additionally, former patients asked for improved accessibility of health services, counselling and economic support. Conclusions These findings can be used to improve clinical management and to guide the international research agenda.
Genetic Susceptibility and Predictors of Paradoxical Reactions in Buruli Ulcer
(PLOS Neglected Tropical Diseases, 2016-04-20) Barogui, Yves Thierry; Klis, Sandor-Adrian; Johnson, Roch Christian; Phillips, Richard Odame; Veer, Eveline van der; et. al
Buruli ulcer is an infectious disease of skin, subcutaneous fat and sometimes bone, mainly affecting children in West Africa. It is considered as one of the Neglected Tropical Diseases but the disease occurs also in moderate climates like South East Australia and Japan where it may also affect adults. Once a patient has started antibiotic treatment, lesions may increase in size even if the antimicrobial treatment is effective; this is highly confusing for doctors and patients as they may think that treatment actually fails. The cause of Buruli ulcer is Mycobacterium ulcerans, related to other mycobacteria that cause disease in man, like leprosy and tuberculosis. Using data from two different studies in West Africa, we show that these paradoxical reactions are associated with trunk localization and that they occur more often in larger lesions. The chance to develop these reactions appeared partly inherited: carrying the homozygous ins/ins genotype of 3’UTR TGTG 285 polymorphism in the SLC11A1 gene increased the risk of paradoxical reactions. Vitamin D is important for the immune defense against infections by mycobacteria. Vitamin D blood concentrations were not associated with paradoxical reactions; patients generally did well, and we did not need corticosteroid immune suppression to overcome these reactions.
Good Quality of Life in Former Buruli Ulcer Patients with Small Lesions: Long-Term Follow-up of the BURULICO Trial
(PLOS Neglected Tropical Diseases, 2014-07-10) Klis, Sandor; Ranchor, Adelita; Phillips, Richard Odame; Abass, Kabiru M.; Tuah, Wilson; et. al
Background: Buruli Ulcer is a tropical skin disease caused by Mycobacterium ulcerans, which, due to scarring and contractures can lead to stigma and functional limitations. However, recent advances in treatment, combined with increased public health efforts have the potential to significantly improve disease outcome. Objectives: To study the Quality of Life (QoL) of former Buruli Ulcer patients who, in the context of a randomized controlled trial, reported early with small lesions (cross-sectional diameter ,10 cm), and received a full course of antibiotic treatment. Methods: 127 Participants of the BURULICO drug trial in Ghana were revisited. All former patients aged 16 or older completed the Dermatology Life Quality Index (DLQI) and the abbreviated World Health Organization Quality of Life scale (WHOQOL-BREF). The WHOQOL-BREF was also administered to 82 matched healthy controls. Those younger than 16 completed the Childrens’ Dermatology Life Quality Index (CDLQI) only. Results: The median (Inter Quartile Range) score on the DLQI was 0 (0–4), indicating good QoL. 85% of former patients indicated no effect, or only a small effect of the disease on their current life. Former patients also indicated good QoL on the physical and psychological domains of the WHOQOL-BREF, and scored significantly higher than healthy controls on these domains. There was a weak correlation between the DLQI and scar size (r = 0.32; p,0.001). Conclusions: BU patients who report early with small lesions and receive 8 weeks of antimicrobial therapy have a good QoL at long-term follow-up. These findings contrast with the debilitating sequelae often reported in BU, and highlight the importance of early case detection.
Helicobacter pylori Coinfection Is Associated With Decreased Markers of Immune Activation in ART-Naive HIV-Positive and in HIV-Negative Individuals in Ghana
(Oxford University Press, 2015-11-15) Phillips, Richard Odame; Eberhardt, Kirsten Alexandra; Sarfo, Fred Stephen; Dompreh, Albert; Kuffour, Edmund Osei; et. al
Background. Helicobacter pylori coinfection in human immunodeficiency virus (HIV) patients has been associated with higher CD4+ cell counts and lower HIV-1 viral loads, with the underlying mechanisms being unknown. The objective of this study was to investigate the impact of H. pylori infection on markers of T-cell activation in HIVpositive and HIV-negative individuals. Methods. In a cross-sectional, observational study, HIV patients (n = 457) and HIV-negative blood donors (n = 79) presenting to an HIV clinic in Ghana were enrolled. Data on clinical and sociodemographic parameters, CD4+/CD8+ T-cell counts, and HIV-1 viral load were recorded. Helicobacter pylori status was tested using a stool antigen test. Cell surface and intracellular markers related to T-cell immune activation and turnover were quantified by flow cytometry and compared according to HIV and H. pylori status. Results. Helicobacter pylori infection was associated with decreased markers of CD4+ T-cell activation (HLADR+ CD38+CD4+; 22.55% vs 32.70%; P = .002), cell proliferation (Ki67; 15.10% vs 26.80%; P = .016), and immune exhaustion (PD-1; 32.45% vs 40.00%; P = .005) in 243 antiretroviral therapy (ART)–naive patients, but not in 214 patients on ART. In HIV-negative individuals, H. pylori infection was associated with decreased frequencies of activated CD4+ and CD8+ T cells (6.31% vs 10.40%; P = .014 and 18.70% vs 34.85%, P = .006, respectively). Conclusions. Our findings suggest that H. pylori coinfection effectuates a systemic immune modulatory effect with decreased T-cell activation in HIV-positive, ART-naive patients but also in HIV-negative individuals. This findingmight, in part, explain the observed association of H. pylori infection with favorable parameters of HIV disease progression. Clinical Trials Registration. Clinicaltrials.gov NCT01897909.
Hepatitis C Virus (HCV) RNA screening and sequencing using dry plasma spots
(Elsevier B.V., 2017-10) Phillips, Richard Odame; Geretti, Anna Maria; King, Simon; Adjei-Asante, Kwabena; Appiah, Lambert Tetteh; et. al
Background: HCV RNA screening of large sample repositories provides data on HCV epidemic patterns that may help guide control policies. In resource-limited settings, shipment of frozen samples to molecular laboratory facilities and testing of individual samples may be prohibitively expensive. Objective: Our aim was to detect and sequence HCV RNA in a large HIV-positive cohort from Kumasi, Ghana, using pooled and individual dried plasma spots (DPS) produced from samples stored at −80 °C. Study design: In the validation phase, replicate DPS were prepared with six dilutions (500–10,000 IU/ml) of the 4th International Standard for HCV and tested in three independent experiments. In the testing phase, DPS prepared with plasma samples from 875 HIV-positive subjects were pooled for screening, followed by testing of individual DPS of positive pools. Input from individual DPS was two 6 mm punches; pools comprised two punches from each of five DPS. Genotypes were determined by Sanger sequencing of HCV core and NS5B. Results: With the dilution series, sensitivity of HCV RNA detection was ≥2500 IU/ml. Replicate DPS gave intraassay and inter-assay coefficients of variation ≤1.4%. With the stored samples, HCV RNA was detected in 5/175 DPS pools and in one DPS from each positive pool, yielding a HCV RNA prevalence of 5/875 (0.57%; 95% confidence interval 0.07-1.07%). The five samples were sequenced as HCV genotypes 2l and 2r. Discussion: DPS allowed reproducible HCV RNA detection, and pooling effectively contained the cost and labour of screening a previously untested, low-prevalence cohort. DPS were also suitable for HCV sequencing.

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