Department of Pure and Applied Sciences
http://ir.tum.ac.ke/handle/123456789/177
Contains PDF journal articles for this department2024-03-29T06:02:53ZAntimalarial Activity of Nigella sativa L. Seed Extracts and Selection of Resistance in Plasmodium berghei ANKA in a Mouse Model
http://ir.tum.ac.ke/handle/123456789/17569
Antimalarial Activity of Nigella sativa L. Seed Extracts and Selection of Resistance in Plasmodium berghei ANKA in a Mouse Model
Yusuf, Rahma Udu; Oyweri, Job; Gathirwa, Jeremiah
Chemotherapy plays a crucial role in malaria control. However, the main obstacle to treatment has been the rise of
parasite resistance to most antimalarial drugs. Artemisinin-based combination therapies (ACTs) remain the most effective
antimalarial medicines available today. However, malaria parasite tolerance to ACTs is now increasingly prevalent especially in
Southeast Asia presenting the danger of the spread of ACTs resistance to other parts of the world. Consequently, this creates the
need for alternative effective antimalarials. (erefore, this study sought out to determine antimalarial potential, safety, and
resistance development of the extracts in a mouse model. Method. Methanolic and ethyl acetate extracts were obtained by solvent
extraction. (e extracts were assayed for acute toxicity in vivo. Additionally, the two extracts were evaluated for antimalarial
activity in vivo against Plasmodium berghei ANKA strain by the 4-day suppressive test at 500, 250, and 125 mg/kg/day. Packed cell
volume was evaluated to determine anemia manifestation. Finally, continuous drug pressure experiment at 500 mg/kg and DNA
amplification via PCR were conducted. (e amplicons underwent through Sanger sequencing. Results. (ere was no toxicity
realized in the animals at 2000 mg/kg. Importantly, high parasitemia suppression of 75.52% and 75.30% using a dose of 500 mg/kg
of methanolic and ethyl acetate extracts, respectively, was noted. (e extracts were able to reverse packed cell volume reduction.
Nigella sativa-resistant phenotype was selected as delayed parasite clearance. However, there was no change in the nucleotide
sequences of PbMDR1 and PbCRT genes. Conclusion. (e results provide room for future exploitation of the plant as an antimalarial
https://doi.org/10.1155/2021/6165950
2021-02-03T00:00:00ZMalaria Transmission After Artemether-Lumefantrine and Dihydroartemisinin-Piperaquine: A Randomized Trial
http://ir.tum.ac.ke/handle/123456789/17568
Malaria Transmission After Artemether-Lumefantrine and Dihydroartemisinin-Piperaquine: A Randomized Trial
Sawa, Patrick; Shekalaghe, Seif A.; Drakeley, Chris J.; Sutherland, Colin J.; Mweresa, Collins K.; Baidjoe, Amrish Y.; Manjurano, Alphaxard; Kavishe, Reginald A.; Beshir, Khalid B.; Yussuf, Rahma U.; Omar, Sabah A.; Hermsen, Cornelus C.; Okell, Lucy; Schallig, Henk D. F. H.; Sauerwein, Robert W.; Hallett, , Rachel L.; Bousema, Teun
Artemisinin-based combination therapy (ACT) reduces the potential for malaria transmission, compared with non-ACTs. It is unclear whether this effect differs between ACTs.
https://doi.org/10.1093/infdis/jit077
2013-03-06T00:00:00ZStreptococcus pneumoniae serotype epidemiology among PCV-10 vaccinated and unvaccinated children at Gertrude’s Children’s Hospital, Nairobi County: a cross-sectional study
http://ir.tum.ac.ke/handle/123456789/17543
Streptococcus pneumoniae serotype epidemiology among PCV-10 vaccinated and unvaccinated children at Gertrude’s Children’s Hospital, Nairobi County: a cross-sectional study
Walekhwa, Michael; Muturi, Margaret; Gunturu, Revathi; Kenya, Eucharia; Kabera, Beatrice
Background: Serotype replacement and emergence of multidrug resistant S.
pneumoniae has exacerbated the need for continuous regional serotype
surveillance especially in the developing world. We investigated S. pneumoniae
serotypes circulating among vaccinated and unvaccinated children ≤5 years in
Nairobi County post PCV10 era.
Methods: A total of 206 vaccinated and unvaccinated children attending
Gertrude’s Children’s Hospital (GCH) were recruited for this study.
Nasopharyngeal swabs collected using Copan Flocked Swabs were the main
study specimen. Culturing and isolation of S. pneumoniae was done on BA with
gentamicin and BA plates respectively at the GCH main laboratory. Serotyping
was done using the Quellung reaction at the KEMRI-Wellcome Trust, Kilifi.
Results: Out of the 206 subjects sampled, 20.39% (42) were found to be
carriers of S. pneumoniae. About 52% (n=22) of the S. pneumoniae carriers
had received the recommended dose of PCV-10, while 48% (n=20) of the
carriers had not. Almost all (n=41; 19.90% of subjects) isolates contained
non-vaccine type S. pneumoniae serotypes, while n=1 of the serotypes (in
0.49% of subjects) were untypeable. Serotypes 28F, 6A, 11A, 3 and 7C were
prevalent in both vaccinated and unvaccinated children, whereas serotypes
23A, 17F, 35F, 48, 13 and 35B, and 23B, 20, 19B, 21, untypeable, 15B and 39
were found among unvaccinated and vaccinated groups, respectively.
Conclusions: All S. pneumoniae serotypes isolated from the subjects sampled
were non PCV-10 vaccine type. These results therefore highlight the
importance of monitoring and evaluation to provide epidemiological information
to determine the effectiveness of PCV10 in Kenya’s Public health services.
doi: 10.12688/f1000research.14387.2
2018-01-01T00:00:00ZSeroprevalence of foot-and-mouth disease virus in cattle herds raised in Maasai Mara ecosystem in Kenya
http://ir.tum.ac.ke/handle/123456789/17542
Seroprevalence of foot-and-mouth disease virus in cattle herds raised in Maasai Mara ecosystem in Kenya
Nthiwa, Daniel; Bett, Bernard; Odongo, David; Kenya, Eucharia; Wainaina, Martin; Grazioli, Santina; Foglia, Efrem; Brocchi, Emiliana; Alonso, Silvia
A cross-sectional study was carried out to determine foot-and-mouth disease (FMD) seroprevalence and identify risk factors of exposure among cattle herds raised in three zones with different types of land use and progressively distant from the Maasai Mara National Reserve (MMNR) boundary. We selected five villages purposively; two in zone 1 (area < 20 km from the MMNR), another two in zone 2 (area between 20−40 km away from the MMNR) and one in zone 3 (area >40 km away from the MMNR). A total of 1170 cattle sera were collected from 390 herds in all the zones and tested for antibodies against the non-structural proteins (NSPs) of FMD virus (FMDV) using two 3ABC-based Enzyme-Linked Immunosorbent Assay ELISA kits. All sera samples were also screened for serotype-specific antibodies using Solid Phase Competitive ELISA (SPCE) kits (IZSLER, Italy). We targeted FMDV serotypes A, O, South African Territory [SAT] 1 and SAT 2, known to be endemic in East Africa including Kenya. Data on putative risk factors for FMD seropositivity in cattle were collected using a questionnaire. The overall apparent animal-level FMD seroprevalence based on the parallel comparison of the two anti-NSPs ELISA kits was 83.8 % (95 % CI; 81.8–85.9), and differed significantly across zones. Zone 1 had a higher seroprevalence than zones 2 and 3 (χ2 = 116.1, df = 2, p < 0.001). In decreasing order, the overall seroprevalences of FMDV serotypes A, SAT 2, O and SAT 1 were 26.3 % (95 % CI; 23.5–29.2), 21.4 % (95 % CI; 18.8–24.0), 21.2 % (95 % CI; 18.7–23.9) and 13.1 % (95 % CI; 11.1–15.3), respectively. The distribution of these serotypes differed significantly between zones (p < 0.05) except for SAT 2 serotype (χ2 = 0.90, df = 2, p = 0.639). Both serotypes A and O were more prevalent in zones 1 and 2 than zone 3 while serotype SAT 1, was higher in zone 3 compared to other zones. The results of multivariable analyses identified animal sex (i.e., female), raising of cattle in zones 1 and 2 (areas < 40 km away from the MMNR); mixing of cattle from multiple herds at watering points, and pastoral husbandry practices, as significant predictors of animal-level FMD seropositivity. This study established that FMD seroprevalence declined with distance from the MMNR.
https://doi.org/10.1016/j.prevetmed.2020.104929
2020-01-01T00:00:00Z