Gabriel Kigen

Bio: Gabriel Kigen is an academic researcher from Moi University. The author has contributed to research in topics: Genome-wide association study & Whole genome sequencing. The author has an hindex of 10, co-authored 28 publications receiving 385 citations. Previous affiliations of Gabriel Kigen include University of Liverpool & Indiana University.

A study of the medicinal plants used by the Marakwet Community in Kenya

Abstract: Background: The medicinal plants used by herbalists in Kenya have not been well documented, despite their widespread use. The threat of complete disappearance of the knowledge on herbal medicine from factors such as deforestation, lack of proper regulation, overexploitation and sociocultural issues warrants an urgent need to document the information. The purpose of the study was to document information on medicinal plants used by herbalists in Marakwet District towards the utilization of indigenous ethnobotanical knowledge for the advancement of biomedical research and development. Methods: Semi- structured oral interviews were conducted with 112 practicing herbalists. The types of plants used were identified and the conditions treated recorded. Results: Herbal practice is still common in the district, and 111 plants were identified to have medicinal or related uses. Different herbal preparations including fruits and healing vegetables are employed in the treatment of various medical conditions. Veterinary uses and pesticides were also recorded. Conclusion: The study provides comprehensive ethnobotanical information about herbal medicine and healing methods among the Marakwet community. The identification of the active ingredients of the plants used by the herbalists may provide some useful leads for the development of new drugs.

Current trends of Traditional Herbal Medicine Practice in Kenya: A review

Abstract: The use of herbal medicine is increasingly finding more relevance today, especially with the recognition that we are facing more challenges in the treatment of some medical conditions such as diabetes and cancer. To date, there are not many publications or records on the traditional herbal medicine use among the various Kenyan communities despite the widespread use. There is therefore an urgent need to document traditional medicines in Kenya for future reference and research. The main objective of this review is to examine the current state of traditional herbal medicine practise in Kenya, the challenges facing the sector and the possible solutions to streamline the practice and maximize on the benefits. The method adopted in this research involved the analysis of the available records on herbal medicine in Kenya from various sources including internet and the available books. This information was then compared with those in other countries with established systems in order to establish the existing inadequacies. The various efforts to document herbal medicine incorporate into mainstream healthcare and the legal framework was also reviewed. Key words: Herbal medicine, documentation, research

Prevalence of potential drug-drug interactions involving antiretroviral drugs in a large Kenyan cohort

Abstract: Background: Clinically significant drug-drug interactions (CSDIs) involving antiretrovirals are frequent and under-recognizedin developed countries, but data are lacking for developing countries. Methodology and Principal Findings: To investigate the prevalence of CSDIs between antiretrovirals and coadministered drugs, we surveyed prescriptions dispensed in a large HIV clinic in Kenya. Of 1040 consecutive patients screened, 996 were eligible for inclusion. CSDIs were defined as ‘major’ (capable of causing severe or permanent damage, contraindicated, avoid or not recommended by the manufacturer, or requiring dose modification) ‘moderate’ (manufacturers advise caution, or close monitoring, or capable of causing clinical deterioration). A total of 334 patients (33.5%) were at risk for a CSDI, potentially lowering antiretroviral drug concentrations in 120 (12%) patients. Major interactions most frequently involved rifampicin (12.4%, mostly with efavirenz) and azoles (2.7%) whereas moderate interactions were frequently azoles (13%), steroids (11%), and antimalarials (3%). Multivariable analyses suggested that patients at risk for CSDIs had lower CD4 counts (P = 0.006) and baseline weight (P = 0.023) and WHO Stage 3 or 4 disease (P#0.007). Risk for CSDIs was not associated with particular regimens, although only 116 (11.6%) patients were receiving WHO second line regimens. Conclusions: One in three patients receiving antiretrovirals in our programme were at risk of CSDIs. Strategies need to be urgently developed to avoid important drug interactions, to identify early markers of toxicity and to manage unavoidable interactions safely in order to reduce risk of harm, and to maximize the effectiveness of mass antiretroviral deployment in Africa.

Ethnomedicinal Plants Traditionally Used by the Keiyo Community in Elgeyo Marakwet County, Kenya

Abstract: Objective:Traditional medicinal plants have long been used to treat various ailments in Keiyo district. However to date there are no records on medicinal plants used by the Keiyo despite threats of rapid disappearance of indigenous knowledge from deforestation, overexploitation among other factors. The purpose of the study was to document medicinal plants used by the Keiyo community in order to preserve traditional medical knowledge for future research and potential development of new drugs. Methods:The research team comprised of professionals from the fields of medicine and botany. Local leaders, community elders, church leaders and other stakeholders were used to identify herbalists and convince them to provide information. Semi structured interviews, group discussions and observations were used to collect information on traditional knowledge from herbalists. Details of the medical conditions treated, herbal preparations used, treatment methods, local plant names and methods of collection of herbs were recorded. Results:A total of 73 medicinal plant species belonging to 33 families were identified, used to treat 46 common human and three veterinary diseases. Leucas calostachys was the most widely used (17 medicinal uses) followed by Vachelia xanthophloea (10), Carissa edulis (9), Trimeria grandifolia (8), Terminalia brownii (7) and Rhamnus prinoides (6). Heartburn was treated using the largest number of plants (17) followed by cancer (9). Eight plants were used to either treat infertility in women or arthritis, whereas peptic ulcers, hypertension, headache, chest congestion and colic pains were each treated using seven plants. Conclusions:The study provides information on medicinal and healing methods used by the Keiyo community. It also revealed that traditional medicines are still widely used in Keiyo district. Some of the identified plants have been demonstrated to possess pharmacological activities related to those mentioned by the herbalists.

Low-coverage sequencing cost-effectively detects known and novel variation in underrepresented populations.

Abstract: Genetic studies in underrepresented populations identify disproportionate numbers of novel associations. However, most genetic studies use genotyping arrays and sequenced reference panels that best capture variation most common in European ancestry populations. To compare data generation strategies best suited for underrepresented populations, we sequenced the whole genomes of 91 individuals to high coverage as part of the Neuropsychiatric Genetics of African Population-Psychosis (NeuroGAP-Psychosis) study with participants from Ethiopia, Kenya, South Africa, and Uganda. We used a downsampling approach to evaluate the quality of two cost-effective data generation strategies, GWAS arrays versus low-coverage sequencing, by calculating the concordance of imputed variants from these technologies with those from deep whole-genome sequencing data. We show that low-coverage sequencing at a depth of ≥4× captures variants of all frequencies more accurately than all commonly used GWAS arrays investigated and at a comparable cost. Lower depths of sequencing (0.5-1×) performed comparably to commonly used low-density GWAS arrays. Low-coverage sequencing is also sensitive to novel variation; 4× sequencing detects 45% of singletons and 95% of common variants identified in high-coverage African whole genomes. Low-coverage sequencing approaches surmount the problems induced by the ascertainment of common genotyping arrays, effectively identify novel variation particularly in underrepresented populations, and present opportunities to enhance variant discovery at a cost similar to traditional approaches.

British HIV Association guidelines for the treatment of HIV-1-positive adults with antiretroviral therapy 2012

Abstract: The overall purpose of these guidelines is to provide guidance on best clinical practice in the treatment and management of adults with HIV infection with antiretroviral therapy (ART). The scope includes: (i) guidance on the initiation of ART in those previously naive to therapy; (ii)support of patients on treatment; (iii) management of patients experiencing virological failure; and (iv) recommendations in specific patient populations where other factors need to be taken into consideration. The guidelines are aimed at clinical professionals directly involved with and responsible for the care of adults with HIV infection and at community advocates responsible for promoting the best interests and care of HIV-positive adults. They should be read in conjunction with other published BHIVA guidelines.

Patient-Reported Barriers to Adherence to Antiretroviral Therapy: A Systematic Review and Meta-Analysis

Abstract: CITATION: Shubber, Z., et al. 2016. Patient-reported barriers to adherence to antiretroviral therapy : a systematic review and meta-analysis. PLoS Medicine, 13(1):e1002183, doi:10.1371/journal.pmed.1002183.

Ethnobotanical survey of medicinal plant species used by communities around Mabira Central Forest Reserve, Uganda

Abstract: An ethnobotanical study of medicinal plants was carried out in 14 villages adjacent to Mabira Central Forest Reserve (CFR) in Central Uganda between August 2013 and March 2014. Information was obtained through interviews using semi- structured questionnaires. Field excursions with traditional healers and herbal medicine collectors were carried out. Descriptive statistics were used to present the data. Fidelity ratios and Informant consensus agreements were calculated. A total of 190 plant species in 61 families and 152 genera were reported in the treatment of various health conditions. Family Fabaceae was dominant representing 14 % of the plant species documented. Vernonia amygdalina was the preferred species for treating malaria. Leaves (68 %) were the most frequently used parts in preparing herbal remedies. Decoctions (29 %) and oral route (53 %) of administration were commonly used method of herbal medicine preparation and administration respectively. Fifty-eight health conditions grouped in 25 categories were treated using medicinal plants. Informant consensus agreement was highest for blood system disorders (0.9) that included anaemia, hypertension and blood cleansing indicating homogeneity of informant’s knowledge about remedies used. Vernonia amygdalina and Erythrina abyssinica had 100 % fidelity level for treatment of malaria and vomiting respectively. The diversity of medicinal plant species used and the associated indigenous knowledge are of great value to the local community and their conservation and preservation is paramount. The therapeutic uses of the documented plants provides basic data for further research focused on pharmacological studies and conservation of the most important species.

A study of the medicinal plants used by the Marakwet Community in Kenya

Abstract: Background: The medicinal plants used by herbalists in Kenya have not been well documented, despite their widespread use. The threat of complete disappearance of the knowledge on herbal medicine from factors such as deforestation, lack of proper regulation, overexploitation and sociocultural issues warrants an urgent need to document the information. The purpose of the study was to document information on medicinal plants used by herbalists in Marakwet District towards the utilization of indigenous ethnobotanical knowledge for the advancement of biomedical research and development. Methods: Semi- structured oral interviews were conducted with 112 practicing herbalists. The types of plants used were identified and the conditions treated recorded. Results: Herbal practice is still common in the district, and 111 plants were identified to have medicinal or related uses. Different herbal preparations including fruits and healing vegetables are employed in the treatment of various medical conditions. Veterinary uses and pesticides were also recorded. Conclusion: The study provides comprehensive ethnobotanical information about herbal medicine and healing methods among the Marakwet community. The identification of the active ingredients of the plants used by the herbalists may provide some useful leads for the development of new drugs.