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An Investigation of the Antimicrobial Activity of Acmella caulirhiza
Get PDFBackground: Acmella caulirhiza is a plant that is used traditionally to treat several disorders such as mouth ulcers, sore throat, toothache and earache, among others. It is a small annual or perennial herb whose location is widespread worldwide. Objectives: The objective of the study was to determine whether the leaves, stem and the flowers extract of the plant possess antibacterial and antifungal activity and to find out which part of the plant is the most active, if any. Methodology: Acmella caulirhiza was collected from the wild in Kericho County. The flower heads, the leaves and the stems were dried separately, ground into a powder and extracted with chloroform. The plant extracts were tested for activity against Escherichia Coli, Staphylococcus aureus, Candida albicans and Bacillus pumilus. Results and Discussion: The plant extracts inhibited the growth of Escherichia Coli, Staphylococcus aureus and Bacillus pumilus. The activity was highest in the stems extracts. The extracts, however, did not have any anti-fungal activity when tested against Candida albicans. It was concluded from these results that the anti-bacterial activity may aid in the efficacy when the plant is used to treat mouth ulcers or sore throat. Key words: Acmella caulirhiza, anti-fungal activity, anti-bacterial activity, traditional medicin
Microbial Quality of Unregulated Herbal Medicinal Products in Kenya
Get PDFBackground: The use of herbal medicines is global, with the majority of the world’s population depending on traditional medicines, particularly herbal remedies for their primary healthcare needs. In Kenya, it is estimated that conventional healthcare system provides for approximately 30 % of the population, while nearly 70 % rely on herbal remedies. Herbal medicines, however, present safety concerns as they carry a relatively high risk of contamination by pathogenic microbes, organic and inorganic pollutants including toxic metals and non-metals, organic, mycotoxins, endotoxins, and agrochemical residues. Objective: This study was designed to assess the microbial quality of regulated and unregulated herbal medicinal products in diverse Kenyan markets, such as the supermarkets, roadside vendors, retail pharmacies and herbal clinics, for levels of microbial contaminants. Materials and Methods: Thirty samples of registered and unregistered herbal medicinal products were collected by purposive sampling from five Kenyan provinces. Microbial load analysis was performed in accordance to pharmacopoeial methods (BP and USP). Microorganisms were further isolated and characterized using differential and selective media and by biochemical analyses. Results: All registered products had microbial load below 100 cfu/ml, and complied with BP and USP requirements. However, none of the unregistered samples complied with pharmacopoeial limits for either or both bacterial and fungal load limits. Most of the unregistered samples had microbial loads ranging from 3.00×106 to 1.56 × 1010 cfu/ml, thus exceeding by far BP or USP standards. The microbial isolates belonged to fifteen (15) different bacterial genera and seven (7) fungal genera. Escherichia coli was the most frequently isolated bacteria from 75 % of the unregistered product samples while Klebsiella pneumoniae, Enterobacter aerogenes, and Staphylococcus aureus followed in 70 %, 60 % and 45 % of the samples, respectively. Salmonella spp was isolated in 40 % of the samples while Shigella spp was found in 20 % of the samples. Conclusion: Unregulated herbal medicinal products that are available in diverse Kenyan markets show poor microbial quality and exhibit contamination by pathogenic microorganisms. There is need to extend regulatory control by the drug authorities to herbal medicinal products to enhance microbial quality and safety. Keywords: Microbial contaminants, herbal medicines, microbial loa
Anti-inflammatory and analgesic effects of Lonchocarpus cyanescens root in mice - Supporting Information
No full textBackground: The root of Lonchocarpus cyanescens is one common remedy of the Ibibios of Akwa Ibom State, Nigeria for the treatment of pain and inflammatory disorders. Objective: To study and validate the anti-inflammatory and analgesic potentials of the ethanol extract and fractions of L. cyanescens root in mice. Methodology: The ethanol extract and the partitioned fractions were tested using carrageenan-induced inflammation, xylene–induced ear oedema models as well as on pains induced chemically and thermally in mice. Results: L. cyanescens root extract and fractions demonstrated anti-inflammatory effects in all the models, suppressed acute oedema as well as exhibited dose and time dependent analgesic properties with butanol fraction showing the highest effects. Discussion: Since the extract and its fractions significantly affected oedema and pain in the various models of this study, it therefore justify the use of the root traditionally in the treatment of pain and inflammatory diseases. Keywords: Anti-inflammatory, analgesic, pain, Lonchocarpus cyanescen
Investigation of Prader-Willi-like Phenotype using a Whole Genome Array
Get PDFIntroductionPrader-Willi syndrome (PWS) is characterised byobesity, short stature, small hands and feet, neonatalhypotonia with difficulty in feeding at birth,hypogonadism and eye problems. At about two years ofage the feeding difficulties with poor suck are graduallyreplaced by hyperphagia and obsession with food,leading to the obesity. In addition to developmentaldelay which is manifested by short stature, small handsand feet, growth hormone deficiency andhypogenitalism/hypogonadism, there are alsobehavioural characteristics including learningdisabilities, temper tantrums, aggression, repetitivespeech, obsessive compulsive behaviour, sleep disorderand skin picking (Cassidy and Driscoll, 2009). Thisdisparate collection of symptoms led Holm et al (1993)to define the major and minor characteristics whichallowed a clinical diagnosis of this the most commongenetic form of obesity. Consensus diagnostic criteriawere defined and weighted scores in which the majorcriteria were awarded one point and the minor criteriahalf a point calculated. A score of 8 or more is clinicallydiagnostic for PWS.The majority of people with PWS have a paternallyderived deletion of approximately 5-7Mb in 15q11-q13,others have maternal disomy of chromosome 15(UPD15mat) and a minority have a defect of theimprinting centre located in exon 1 of the SNRPN genewhich leads to a maternal imprint on the paternallyderived chromosome. Any of these abnormalities willresult in loss of the paternal contribution to the Prader-Willi syndrome critical region (PWSCR), demonstratedby loss of a paternally derived unmethylated band at theimprinting centre and a lack of expression of the SNRPNgene. Although these do not differentiate between thedifferent genetic types of PWS they are diagnostic forthe syndrome (Cassidy and Driscoll, 2009; Ramsden etal, 2010; Zeschnigk et al, 1997).Within 15q11-q13 the complex imprintedSNURF/SNRPN gene hosts several untranslated snoRNAgenes located within intronic sequences. The finding ofa microdeletion involving SNORD116 in a boy with PWSled to the identification of this snoRNA as the candidategene for the syndrome (Sahoo et al, 2008).In the course of a large study of PWS in the UK(Whittington et al, 2001; Soni et al, 2007) three peoplewere identified who fulfilled the criteria for a clinicaldiagnosis of the syndrome but not the geneticlaboratory diagnostic criteria.The Affymetrix Cytogenetics Whole-Genome 2.7M arraywhile providing high resolution whole genome coveragereliably detects changes in copy number. Deletionsand/or duplications present in all three participants ifinvolved in annotated genes could potentiallycontribute to the Prader-Willi-like phenotype.Candidate genes can subsequently be evaluated toestimate their transcription levels and compared withthose shown by people with PWS and with unaffectedindividuals
Amino Acid changes at the hemagglutinin antigenic site amongst Kenyan influenza A(H1N1)pdm09 viruses in 2009-2010
No full textBackground: Influenza viruses evolve very rapidly and mutations in the HA1 gene can lead to genetic drifts necessitating alterations in the annual vaccine formulations. It is therefore important to constantly monitor evolution of these viruses globally for timely detection and interventions to such events. Objective: To study the changes that occurred within antigenic HA1 protein of the influenza A(H1N1)pdm09 viruses that circulated in Kenya at the height of the 2009 influenza pandemic. Methodology: Nasopharyngeal samples from patients meeting the WHO pandemic influenza case definition were collected from consenting patients between 2009 and 2010 from across Kenya. The detection of influenza A(H1N1)pdm09 viruses was carried out using real-time RT-PCR. The positive samples were then cultured in MDCK cells and confirmed using the HAI assay. 23 isolates from this period were selected for RNA extraction followed by PCR amplification of the HA1 gene segments. Nucleotide sequencing was performed using the Sanger method followed by data analysis using a suite of bioinformatics tools. Results: HAI assays showed that the Kenyan isolates were antigenically similar to A/California/07/2009 vaccine strain. However, at the genetic level, all Kenyan isolates had P83S, S203T and I321V parallel amino acid changes in the HA1 protein not present in the vaccine strain. The P83S change occurred in the Cb antigenic binding site. Additionally all the 2010 Kenyan isolates except isolates A/Kenya/057/2010 and A/Kenya/059/2010 had D97N, S185T and E374K amino acid changes when compared to the vaccine strain. The Kenyan isolates A/Kenyan/057/2010 and A/Kenyan/059/2010 showed K142R amino acid changes instead. There were other mutations which occurred randomly among the Kenyan individual isolates, these included changes such as N129D on (A/Kenyan/0015/2009, A/Kenya/0043/2009, and A/Kenya/0016/2009), K142R on (A/Kenyan/057/2010 and A/Kenya/059/2010) and G170R change which were present in the A/Kenya/057/2010 isolate. These other mutation occurred at Sa, Ca2 and Ca1 antigenic sites of the HA1 protein. Conclusion: Our results show that although amino acid changes rapidly occurred on antibody binding sites of HA1 protein, the antigenicity of the protein was retained and that the A/California/07/2009 vaccine strain component was appropriate for Kenya
Factors associated with mother to child transmission of Human Immunodeficiency Virus in Kenya
No full textIntroduction: In Kenya, provision of Early Infant Diagnosis (EID) of HIV using PCR nationwide was commenced in 2006 free of charge. Objectives: Our objective was to determine the impact antiretroviral therapy has had on infant HIV in Kenya, and to describe the factors associated with transmission of HIV from mothers to infants. Methodology: This was a cross sectional descriptive study. Dried blood spot samples collected from infants from all over the country were sent to the testing laboratories in KEMRI and tested for HIV using the Abbot M2000SP of the Cobas Ampliprep-Cobas Taqman platforms. All data analysis was done using Stata SE Version 12 for Mac OSX Mountain Lion. Results: A total of 32,671 infant samples were tested between January 2010 and March 2012. 29,571 (91.5%) infants were HIV negative and 2,666 (8.3%) were HIV positive. The odds of being seropositive were higher in females (OR 1.15, p=0.0010) overall, and were also higher than for males in most age categories. The odds of positivity associated with exclusive breastfeeding before 6 months were 0.48 (p = 0.0000), exclusive replacement feeding before 6 months 0.77 (p = 0.0393), mixed feeding before 6 months 1.88 (p= 0.0000), breastfeeding after 6 months 2.14 (p= 0.0000), and not breastfeeding after 6 months 1.66 (p= 0.0000). The odds of seropositivity were 2.54 (p=0.0000) in the absence of maternal prophylaxis and 2.96 (p= 0.0000) without infant prophylaxis. All other prophylactic approaches were associated with lower odds of seropositivity. Babies who received no prophylaxis and breastfed beyond six months, whose mothers received no prophylaxis, faced the highest seropositivity odds (OR 2.11, p = 0.0086). Conclusion: The transmission rates of HIV from mother to child in Kenya are low. Regardless of age, female infants are more likely to test HIV positive than their male counterparts. The highest odds of seropositivity are in babies who receive no prophylaxis and breastfeed beyond six months, and whose mothers receive no prophylaxis
Analyses of selection pressure on the Hemagglutinin gene of influenza A/H3N2 Viruses circulating in Kenya 2007-2011
No full textBackground: The hemagglutinin (HA) gene of Influenza viruses, especially the HA1 portion, exhibits a rapid rate of change, largely in response to human immune surveillance in a partially immune human population. Mutations in influenza viral genes accumulate over time and are under selection pressure during epidemics or pandemics. Objective: To determine whether the Kenyan influenza A/H3N2 viruses are undergoing adaptive evolution to become epidemic threats. Methods: Nasopharyngeal samples from patients meeting the WHO ILI case definition were collected between 2007 and 2010 from across Kenya. The detection of H3N2 virus was carried out using real-time RT-PCR. Positive samples were then cultured in MDCK cells and confirmed using the HAI assay. 156 isolates from this period were selected for amplification of the HA1 portion of the HA gene and the resulting amplicons sequenced. Global estimates, ω, of dN and dS, averaged over the entire alignment, were compared to calculate the overall strength of selection using the HyPhy 2.0 software package implemented in datamonkey. Results: Analysis of neutrality using, Kumar’s method showed that ω varied from 0.50 in 2007, 0.36 in 2008, 0.32 in 2009, 0.61 in 2010 and 0.41 in 2011. Further site by site analysis identified amino acid positions 46, 158 and 173 to be under positive selection. Analysis of differential selection showed 7 sites that harbored two or more amino acid substitutions. Amino acid positions 158, 160 and 189 had the highest number of amino acid polymorphisms. Conclusions: Overall, this study shows that local Influenza A(H3N2) viruses have been evolving via a series of ‘adaptive bursts’ characterized by positive selection occurring largely in immunological epitopes B and D. In between these bursts there is little evidence for positive selection and newly-emergent strains slowly replace the existent strains. Based on this study alone, we propose that these bursts occur after every two years. Since in a single population, dN/dS <1does not follow monotonic function, it is difficult to infer selection pressure in these results. However, by focusing on the antigenic sites we were able to observe an evolutionary pattern in the Kenyan samples. Thus evolution of Kenyan Influenza A(H3N2) is characterized by non synonymous changes followed by a period of stasis that is then followed by another period of non synonymous changes which is followed by purification selection
Development of Rapid Diagnostics and Establishment of an Alert system for outbreaks of Yellow Fever and Rift Valley fever in Kenya
No full textBackground: Outbreaks of arthropod borne viruses occur periodically in Kenya, and cause significant morbidity and mortality. Yellow Fever Virus, Chikungunya Virus, Dengue Virus and Rift Valley Fever Virus are some of the most important arboviruses. Definitive diagnosis takes several days, partially because point of care tests (POCTs) are not available. Such tests could help speed up diagnosis and if coupled with mHealth and eHealth, can strengthen the surveillance network for disease outbreaks and facilitate timely interventions that can reduce morbidity and slow down the spread of these diseases. Methods: Our research team has assembled expertise to develop and produce POCTs for YF virus and RVF virus and to design an early vigilance model against outbreaks of these arbovirus infections in partnership with MOPHS. We have successfully applied for and received funding from the Science and Technology Research Partnership for Sustainable Development (SATREPS Program, which is funded by JICA and JST) for five years to do this. Expected results: In addition to developing POCTs and assembling an alert network, we expect to strengthen both the KEMRI Production Department (PD) and the Arboviruses and Hemorrhagic Fevers Reference Laboratory, and to build a field surveillance laboratory at KEMRI-Centre for Infectious and Parasitic Diseases Control Research (CIPDCR) in Alupe
Viral Hemorrhagic Fever Surveillance, Laboratory Testing, and Outbreak Response in Uganda: 2010-2012
No full textBackground: Uganda is endemic for viral hemorrhagic fevers (VHFs) and other zoonotic diseases. Beginning in July 2010 the Viral Special Pathogens Branch (VSPB), CDC, the Uganda Virus Research Institute (UVRI), and the Ministry of Health (MOH) established a first of it’s kind National VHF surveillance program. In addition, a permanent National VHF diagnostics reference laboratory has been established at the UVRI in Entebbe. Objective: To establish and maintain a National standardized, integrated, viral hemorrhagic fever surveillance system in Uganda that will detect the first instances of suspect VHFs, report them to rapidly report them to the national level, and perform rule-out testing within 24 hours of sample receipt. Methodology: Training on VHF case definitions, data collection, and clinical case identification was carried out at 6 VHF sentinel sites. Training on safe sample collection and transport was also performed. Results: Since July 2010, 6 sentinel VHF surveillance sites were established and over 30 clinical and laboratory staff were trained on case identification, reporting, and sample collection for suspect cases. The laboratory has tested over 1000 clinical samples for suspect VHFs and serosurveys. The program identified an outbreak of Yellow Fever in Northern Uganda in 2010. The program also confirmed three outbreaks of Ebola hemorrhagic fever. The first was a single Ebola case in Luwero district in May, 2011. The second outbreak was in Kibaale District, Uganda in June 2012. 115 suspect, 13 probable, and 11 laboratory confirmed Ebola cases were identified (CFR=67%). A third outbreak was confirmed in Isiro, DRC and is currently ongoing. The VHF surveillance program continues to receive suspect VHF case reports from Uganda and the region. Conclusions: Rapid identification and confirmation of VHF cases has led to the rapid response and containment of recent outbreaks in Uganda and DRC. Continued efforts are needed to build and sustain VHF surveillance networks throughout Africa
Surveillance of Human Parainfluenza viruses in Kenya during the 2007-2011 Period
No full textBackground: Human parainfluenza viruses (HPIVs) belong to the paramyxoviridae family and are classified into four types. These viruses account for a large percentage of pediatric respiratory disease, including syndromes such as upper respiratory tract infections (URTIs), laryngotracheobronchitis (croup), bronchiolitis, and pneumonia. HPIV is the major cause of croup in which type 1 is most frequent cause, followed by type 3 and type 2 respectively. In January 2007, through an existing influenza surveillance network, the Kenyan National Influenza center started screening for parainfluenza and other non-influenza respiratory viruses within the designated Influenza surveillance network made up of eight sentinel sites spread throughout the country. Objective: The objective of this study was to monitor and document circulation of Human parainfluenza viruses in Kenya in the period 2007-2011. Methodology: Specimens were collected from the nasopharynx using a flocked swab from consenting patients meeting the WHO influenza-like-illness (ILI) case definition. Specimens were transported to the NIC while observing the cold chain and inoculated into LLCMK2 cell line. After incubation and observation for cytopathic effect, all samples were screened by direct immunofluorescence assay (IFA) using the Respiratory Panel I Viral Screening and Identification kit (Chemicon International, Inc). Results: 14,990 nasopharyngeal swab samples were collected between January 2007-October 2011. HPIV were detected in 801 (5.3%) cases. 361 (45%) of the detections were HPIV-3 followed by HPIV-1 in 296 (37%) and 144 (18%) for HPIV-2 respectively. This confirms what has been observed elsewhere that HPIV1 and HPIV3 are the most frequently detected types. Analyses of co-infections involving HPIVs showed that HPIV1/HPIV2 (16cases) were the most frequent followed by HPIV1/HPIV3 (15) cases and HPIV2/HPIV3 (15 cases). There were 30 cases of triple infections of HPIV1/HPIV2/HPIV3. Generally, parainfluenza viruses circulated throughout the period under study. Parainfluenza virus infections were observed throughout the year with no distinct seasonal patterns. Conclusion: This study shows that parainfluenza viruses contributed to a significant level to the respiratory disease burden in Kenya in 2007-2011. Furthermore, our study has shown that parainfluenza viruses circulated in the human population in Kenya throughout the study period and did not show any distinct seasonality