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A Monitoring System for Transboundary Foot and Mouth Disease (FMD) considering the Demographic Characteristics in Gairo, Tanzania
Get PDFThis research article was published in the Engineering, Technology & Applied Science Research Vol. 11, No. 4, 2021-Foot and Mouth Disease (FMD) is present in many
countries, including Tanzania. Gairo is among the districts that
frequently face FMD. This study found that the current
mechanism for communicating FMD in Gairo district suffers
from a long chain of information flow that causes delay and
insufficient information for FMD control. Therefore, this study
aimed to explore the implementation of an information system
named "Monitoring System for Transboundary Foot and Mouth
Disease," developed purposely to provide a standard platform for
communicating FMD between livestock keepers and other
stakeholders in the district. The system enables timely sharing of
FMD events such as outbreaks, precaution measures, clinical
signs, and negative impacts using Short Message Services (SMS),
Unstructured Supplementary Service Data (USSD), and Voice
Calls (robo-calls) through the mobile phones. Also, livestock
keepers may report FMD outbreaks direct to the system using
feature phones. The Statistical Package for Social Sciences
(SPSS) was used to analyze data and Microsoft Visio was used for
drawing the system architecture and information flow diagram.
Finally, the system was implemented using PHP hypertext
processor, JQuery, HTML, JSON, JavaScript, MySQL, and
Apache webserver
Conjugative Plasmids Disseminating CTX-M-15 among Human, Animals and the Environment in Mwanza Tanzania: A Need to Intensify One Health Approach
Get PDFThis research article was published in the Journals Antibiotics, Volume 10, Issue 7, 2021Background: Globally, blaCTX-M-15 beta-lactamases are the most popular extended spectrum beta-lactamase alleles that are widely distributed due its mobilisation by mobile genetic elements in several compartments. We aimed to determine the conjugation frequencies and replicon types associated with plasmids carrying blaCTX-M-15 gene from Extended Spectrum Beta-lactamase producing isolates in order to understand the dissemination of resistance genes in different compartments. Material and methods: A total of 51 archived isolates carrying blaCTX-M-15 beta-lactamases were used as donors in this study. Antibiotic susceptibility tests were performed as previously described for both donors and transconjugants. Conjugation experiment was performed by a modified protocol of the plate mating experiment, and plasmid replicon types were screened among donor and transconjugant isolates by multiplex Polymerase Chain Reaction in a set of three primer panels. Results: The conjugation efficiency of plasmids carrying blaCTX-M-15 was 88.2% (45/51) with conjugation frequencies in the order of 10−1 to 10−9 and a 100% transfer efficiency observed among E. coli of animal origin. Majority of donors (n = 21) and transconjugants (n = 14) plasmids were typed as either Inc FIA or Inc FIB. Resistance to non-beta-lactam antibiotics was transferrable in 34/45 (75.6%) of events. Ciprofloxacin, tetracycline and sulphamethoxazole-trimethoprim resistance was co-transferred in 29/34 (85.3%) such events. Gentamicin resistance was transferred in 17/34 (50%) of events. Conclusions: Majority of plasmids carrying blaCTX-M-15 were conjugatively transferred by IncF plasmids along with non-beta lactam resistance. There is a need for more research on plasmids to understand how plasmids especially multi replicon plasmids interact and the effect of such interaction on conjugation. One Health approach is to be intensified to address antimicrobial resistance which is a public health threat
Ensemble-based screening of natural products and FDA-approved drugs identified potent inhibitors of SARS-CoV-2 that work with two distinct mechanisms
Get PDFThis research article was published in the Elsevier Journal of Molecular Graphics and Modelling Volume 105, February 2021The recent outbreak of SARS-CoV-2 is responsible for high morbidity and mortality rate across the globe. This requires an urgent identification of drugs and other interventions to overcome this pandemic. Computational drug repurposing represents an alternative approach to provide a more effective approach in search for COVID-19 drugs. Selected natural product known to have antiviral activities were screened, and based on their hits; a similarity search with FDA approved drugs was performed using computational methods. Obtained drugs from similarity search were assessed for their stability and inhibition against SARS-CoV-2 targets. Diosmin (DB08995) was found to be a promising drug that works with two distinct mechanisms, preventing viral replication and viral fusion into the host cell. Isoquercetin (DB12665) and rutin (DB01698) work by inhibiting viral replication and preventing cell entry, respectively. Our analysis based on molecular dynamics simulation and MM-PBSA binding free energy calculation suggests that diosmin, isoquercetin, rutin and other similar flavone glycosides could serve as SARS-CoV-2 inhibitor, hence an alternative solution to treat COVID-19 upon further clinical validation
Mycobactericidal effect of different regimens measured by molecular bacterial load assay among people treated for multidrug-resistant tuberculosis in Tanzania.
Get PDFThis research article published by the American Society for Microbiology, 2021Rifampicin or multidrug-resistant-tuberculosis (RR/MDR-TB) treatment has largely transitioned to regimens free of the injectable aminoglycoside component despite the drug class' purported bactericidal activity early in treatment. We tested whether () killing rates measured by molecular bacterial load assay (TB-MBLA) in sputa correlate with composition of the RR/MDR-TB regimen. Serial sputa were collected from patients with RR/MDR- and drug-sensitive TB at day 0, 3, 7, 14, and then monthly for 4 months of anti-TB treatment. TB-MBLA was used to quantify viable 16S rRNA in sputum for estimation of colony-forming-unit per mL (eCFU/mL). killing rates were compared among regimens using nonlinear-mixed-effects modelling of repeated measures. Thirty-seven patients produced 296 serial sputa: 13 patients received an injectable-containing but bedaquiline-free reference regimen, 9 received an injectable and bedaquiline-containing regimen, 8 received an all-oral bedaquiline-based regimen, and 7 patients were treated for drug-sensitive TB with conventional rifampin/isoniazid/pyrazinamide/ethambutol (RHZE). Compared to the adjusted killing of -0.17 (95% CI; -0.23 to -0.12) for the injectable-containing but bedaquiline-free reference regimen, the killing rates were -0.62 (95% CI; -1.05 to -0.20) log eCFU/mL for the injectable and bedaquiline-containing regimen (p = 0.019), -0.35 (95% CI; -0.65 to -0.13) log eCFU/mL for the all-oral bedaquiline-based regimen (p = 0.054), and -0.29 (95% CI; -0.78 to +0.22) log eCFU/mL for RHZE (p = 0.332). killing rates from sputa were higher among patients who received bedaquiline but were further improved with the addition of an injectable aminoglycoside
Integrating stakeholders' perspectives and spatial modelling to develop scenarios of future land use and land cover change in northern Tanzania.
Get PDFThis research article published by PLOS ONE, 2021Rapid rates of land use and land cover change (LULCC) in eastern Africa and limited instances of genuinely equal partnerships involving scientists, communities and decision makers challenge the development of robust pathways toward future environmental and socioeconomic sustainability. We use a participatory modelling tool, Kesho, to assess the biophysical, socioeconomic, cultural and governance factors that influenced past (1959-1999) and present (2000-2018) LULCC in northern Tanzania and to simulate four scenarios of land cover change to the year 2030. Simulations of the scenarios used spatial modelling to integrate stakeholders' perceptions of future environmental change with social and environmental data on recent trends in LULCC. From stakeholders' perspectives, between 1959 and 2018, LULCC was influenced by climate variability, availability of natural resources, agriculture expansion, urbanization, tourism growth and legislation governing land access and natural resource management. Among other socio-environmental-political LULCC drivers, the stakeholders envisioned that from 2018 to 2030 LULCC will largely be influenced by land health, natural and economic capital, and political will in implementing land use plans and policies. The projected scenarios suggest that by 2030 agricultural land will have expanded by 8-20% under different scenarios and herbaceous vegetation and forest land cover will be reduced by 2.5-5% and 10-19% respectively. Stakeholder discussions further identified desirable futures in 2030 as those with improved infrastructure, restored degraded landscapes, effective wildlife conservation, and better farming techniques. The undesirable futures in 2030 were those characterized by land degradation, poverty, and cultural loss. Insights from our work identify the implications of future LULCC scenarios on wildlife and cultural conservation and in meeting the Sustainable Development Goals (SDGs) and targets by 2030. The Kesho approach capitalizes on knowledge exchanges among diverse stakeholders, and in the process promotes social learning, provides a sense of ownership of outputs generated, democratizes scientific understanding, and improves the quality and relevance of the outputs
Betanidin isomerisation and decarboxylation, thermodynamic and charge transfer dye properties towards dye sensitised solar cells application
Get PDFThis research article published by John Wiley & Sons, Inc., 2021Along with attractiveness of natural dyes for solar technologies, the instability is a well‐known drawback of the dyes, which impedes their usage for dye sensitised solar cells (DSSCs) application. The planar isomer appeared to be predominant in equilibrium vapour despite its less energetic stability. Both betanidins belong to red–purple pigments betacyanins, which experimentally demonstrated good adsorption in a visible range. In this study, the structural, thermodynamic, and optoelectronic properties of betanidins have been determined from density functional theory (DFT) and time‐dependent DFT (TD–DFT) computations. On the basis of the thermodynamic approach, isomerisation reaction between two structural conformers of betanidin, bent and planar, and also decarboxylation reactions have been analysed. The planar isomer appeared to be predominant in equilibrium vapour despite its less energetic stability; both betanidin molecules exhibit an inclination to decay into decarboxylated betanidin and CO2. As for worthy optoelectronic properties and applicability in DSSCs, the dyes considered satisfy most requirements to sensitise the semiconductor TiO2 and be regenerated by electrolytes. Adsorption of the dyes at the TiO2 surface has been simulated; for the dye@TiO2 complexes, the binding energies, electronic spectra, and relevant molecular orbital (MO) isosurfaces have been computed and discussed
Anthropogenic Pressure on Tree Species Diversity, Composition, and Growth of Balanites aegyptiaca in Dinder Biosphere Reserve, Sudan
Get PDFThis research article published by MDPI, 2021Anthropogenic disturbances, such as illegal harvesting and livestock browsing, often affect
natural forests. However, the resulting tree species diversity, composition, and population structure
have rarely been quantified. We assessed tree species diversity and importance value indices and, in
particular, Balanites aegyptiaca (L.) Del. population structure, across 100 sample plots of 25 m × 40 m
in disturbed and non-disturbed sites at the Dinder Biosphere Reserve, Sudan, from April 2019 to
April 2020. We found that the tree species diversity in non-disturbed sites was more than double that
of disturbed sites (p < 0.001, T = 32.6), and seedlings and saplings comprised more than 72% of the
entire tree population (F2,48 = 116.4, p = 0.034; F2,48 = 163.2, p = 0.021, respectively). The tree density
of B. aegyptiaca in the disturbed site was less than half that of the non-disturbed site (p = 0.018, T = 2.6).
Balanites aegyptiaca was seven times more aggregated in disturbed sites compared to more regularly
spaced trees in non-disturbed sites (T = 39.3 and p < 0.001). The poor B. aegyptiaca population status of
the disturbed site shows that the conservation of this vulnerable species is essential for a sustainable
management and utilization scheme
Predicting land use/cover changes and its association to agricultural production on the slopes of Mount Kilimanjaro, Tanzania
Get PDFThis research article published by Taylor & Francis Online, 2021Increasing demand for food production results in Land use and land cover (LULC) changes, which afflicts the provision of ecosystem services in high mountain areas. This work used time-series LULC and selected spatial metrics to predict the LULC changes for Kikafu-Weruweru-Karanga (KWK) watershed (on the southern slopes of Mt. Kilimanjaro) for the next decade. LULC maps were generated by classifying time-series satellite images. We further predicted the implications for selected staple crop production over the next decade. The simulated LULC shows expansion in built-up (by 32.55%/27.04 km2) and agriculture (by 39.52%/52.0 km2) areas from 2018 to 2030. These results suggest that urbanization is likely the next biggest threat to water availability and food production. Grasslands and wetlands are expected to decrease by 57.24% and 39.29%, respectively. The forest area is likely to shrink by 6.37%, about 9.82 km2, and 1.26 km2 being converted to agriculture and built-up areas, respectively. However, expansion in agricultural land shows very little increase in staple food crop production records, suggesting that farm size plays a minor role in increasing crop production. Predicting the near future LULC around KWK is useful for evaluating the likelihood of achieving development and conservation targets that are set locally, nationally and internationally
Modeling and analysis of taeniasis and cysticercosis transmission dynamics in humans, pigs and cattle
Get PDFThis research article published by Springer Nature, 2021Taeniasis and cysticercosis pose a significant challenge to food safety and public
health. Cysticercosis reduces the market value for pigs and cattle by making pork and
beef unsafe for consumption. In this paper, a mathematical model for the
transmission dynamics of taeniasis and cysticercosis in humans, pigs and cattle is
formulated and analyzed. The analysis shows that both the disease free equilibrium
(DFE) and the endemic equilibrium (EE) exist. To study the dynamics of the diseases,
we derived the basic reproduction number R0 by next generation matrix method.
When R0 1 the EE is
globally asymptotically stable. The normalized forward sensitivity index was used to
determine sensitive parameters to the diseases. Humans’ recruitment rate, probability
of humans’ infection with taeniasis and the defecation rate of taenia eggs by humans
with taeniasis are the most positive sensitive parameters to diseases’ transmission
whereas the human natural death rate is the most negative sensitive parameter.
However, it is biologically unethical and not practical to increase human natural
mortality rate for disease control. In this case, other parameters with negative
sensitivity indices such as death rate of taenia eggs and proportions of unconsumed
infected beef and pork can be considered for disease control. Generally, to control the
diseases, more efforts should be made directed to reducing the number of humans
who have taeniasis and defecate in the open environment. Also meat inspection and
indoor keeping of cattle and pigs should be emphasized
Endophytic Rhizobacteria for Mineral Nutrients Acquisition in Plants: Possible Functions and Ecological Advantages
Get PDFThis book chapter published by Springer Nature Switzerland AG., 2021Nutrient-deficiency in agricultural soils is a major problem in many parts of the world, it is, therefore, artificial fertilizers are widely used to boost crop production. Unfortunately, these fertilizers are associated with a myriad of environmental problems hence, there is a need for viable alternatives. The realization that the plant microbiome can improve plant health, soil fertility, and crop productivity is one of the most fascinating scientific discoveries in the world. For several decades, rhizobacteria have been studied due to their various plant growth-promoting (PGP) traits. Endophytic rhizobacteria are unique plant microbiome that establish themselves within plant root tissues and exert beneficial functions to their hosts without harming them. A lot of emphases have been put on these bacteria as viable tools for sustainable agriculture and it is advanced that they could be better plant growth promoters than their external counterparts. However, this theory is not yet clearly understood. This chapter provides the current state of understanding of the putative functions of endophytic rhizobacteria and their future prospects for plant mineral nutrients acquisition. Their advantageous traits that largely advanced to facilitate these PGP functions are also discussed. Such informations can provide better opportunities for improved plant mineral nutrients acquisition and enhance the application of these microbes as viable strategies for sustainable agriculture