Production and Characterization of Protease from Serratia marcescens

Extracellular protease produced by Serratia marcescens isolated from the gut of termite (Centrocestus formosanus) was investigated in this study. The effect of temperature, pH, carbon and nitrogen sources on protease production was examined. The extracellular protease was separated from the culture supernatant of the organism through precipitation with ammonium sulfate. The protease was purified by Sephadex G-150 gel filtration and diethylaminoethanol (DEAE) - Sephadex A-50 ion exchange chromatography. The effect of temperature, pH, and salts on the proteolytic activity of the enzyme was also investigated. Optimal protease production was obtained after about 12-hour incubation. The optimum temperature and pH for protease production was found to be 40°C and pH 7, respectively. Protease production was highest when rice bran and casein were used as the carbon and nitrogen sources, respectively. The native molecular weight of the protease was estimated to be 56 kDA. The optimal temperature for hydrolysis of casein was 50°C and the optimal pH was 8. The protease was found to be inhibited by ethylenediaminetetraacetic acid (EDTA), NaCl, CaCl2, FeCl2 and HgCl2. Proteolytic activity was however enhanced by KCl. The maximum velocity Vmax and Km values were 40 mg/min/mL and 0.91 mg/mL, respectively

Review of COVID‑19 Vaccine

Coronavirus disease 2019 (COVID‑19) accounts for over 92 million confirmed cases worldwide, with over 2.06 million deaths. In the past year, more than 290 candidate vaccines have been tested; COVID‑19 vaccine  development was sped up, with shortened timeline, due to the urgent global need in the face of the pandemic. In addition, people with the highest risk of contracting the disease, such as health workers with a high risk of exposure, elderlies, and people with underlying comorbidities, were prioritized with vaccination rollout. The article narratively reviewed original and review articles available on PubMed and Google Scholar related to the theme to provide up‑to‑date information. The different templates developed and studied for COVID‑19 vaccines include the whole‑virus vaccine, viral vector vaccine, nucleic acid (deoxyribonucleic acid and ribonucleic acid), and protein subunit vaccine. Myths impede vaccine uptake in this part of the globe. Adopting these myths leads to sharing and spreading, which negatively impacts the prevention of COVID‑19 and vaccine uptake. Adverse event following immunizations (AEFIs) is classified based on severity, from minor to severe. The minor ones are common events that pose no potential health risks to the receiver of the vaccine. The type determines the safety profile, severity, and frequency of AEFIs observed with the vaccine administration. Overall, this pandemichas heightened the global level of threat awareness; it has also provided motivation to prepare for future  pandemics by developing new vaccines

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Highway Development and Capacity Utilisation in Ogun State, Nigeria

Highway development in Nigeria pioneered other modes of transport including rail, air, water and pipeline. It serves as the most efficient means of distributing agricultural products, locally-made products and natural resources. As a result of this, highways requires adequate planning and periodic maintenance for effective and efficient performance. This study examined traffic situation and capacity utilisation of highways in Ogun State, Nigeria with particular reference to Lagos-Ibadan, Lagos-Abeokuta and Sagamu-Benin Highways. Manual traffic count method was employed for the estimation of traffic volume and flow pattern. The count took 12 hours a day for three consecutive days (Tuesday, Thursday and Saturday) of a week. The traffic data gathered were analyzed and interpreted using descriptive and inferential techniques to determine Average Daily Traffic Volume (ADTV), flow situation and capacity utilization rate of each highway through thorough observation of inbound and outbound traffic. Findings revealed significant variation in traffic flow situation observed on Tuesday, Thursday and Saturday of selected highways. Findings also revealed that Lagos-Ibadan Highway (2,085 vehicles/hour/lane) is well utilized while Abeokuta-Lagos and Sagamu-Benin Highways are underutilized with 820 and 1,184 vehicles/hour/lane respectively. Improvement measures and strategies to address traffic flow situation including route development and utilisation issues on the highways were proposed

Travel Behaviour and Mobility Challenges of Disabled Elderly in Selected Cities of Ogun State, Nigeria

The growth of disabled elderly with mobility constraints particularly in developing countries including Nigeria is becoming worrisome. The study examined travel behaviour and mobility challenges of disabled elderly in four cities in Ogun State, Nigeria. Purposive and convenient sampling methods were used to administer 400 questionnaire and data elicited were analyzed descriptively and inferentially. Findings revealed that most of respondents were male (69.5%), aged between 66-70 years (43.5%), and characterized with visual impairment (62%). On travel behaviour, majority generated about 10 trips a week (68.5%), through tricycle (45.5%) and basically for medical purposes (81%). Mobility challenges faced by respondents are mostly deplorable road (92%), inaccessibility to public transport (84%), poor public vehicle condition (76%) and longer-waiting time at bus stops (70%). These challenges have been blamed on weak policy framework and systematic withdrawal of governmentin public transport investment. Furthermore, binary logistics regression result shows that respondents travel behaviour is statistically influenced by their socioeconomic status (p<0.000). The Pseudo R-Square [Cox & Snell’s R-Square (36%) and Nagelkerke’s R (70%)] show that the model is relevant in predicting influence of vehicle ownership on travel behaviour. The study recommended among others, provision of quality public transport scheme with special features for disabled

Driving Behaviour of Taxi Drivers towards Sustainable Public Road Transport in Ogun State, Nigeria

Driving is a psychomotor activity that requires combination of mental concentration and good visual functions. Regrettably, incessant deviant driving behaviour of commercial taxi drivers is worrisome. This study examines the driving behaviour of taxi drivers towards sustainable public road transport in Ogun State, Nigeria. Seven hundred and fifty (750) copies of questionnaire were distributed using multistage and random sampling techniques. Multiple Regression and Analysis of Variance (ANOVA) were used to test postulated hypotheses at 0.05 level of significance. More males (94%) are involved in commercial taxi driving than female (6%); and 91% had driving experience of more than two years. Factors influencing deviant driving behaviour of taxi drivers are intake of alcohol (72%); intake of drugs and other local substances before and while driving (65%); attitudes of traffic officers (96%); traffic situation (90%); demand for services (96%) and vehicle condition (88%). There is statistically significant relationship between years of driving experience and driving behaviour of taxi drivers (F14735 17.118= P&lt;0.05). Meanwhile, nine (9) out of the fourteen (14) predictors best predict driving behaviour of commercial drivers. This study recommends adherence to road safety driving rules and enforcement measures

A qualitative exploration of malaria operational research situation in Nigeria

<div><p>Background</p><p>Malaria, remains one of the leading causes of high morbidity and mortality in Nigeria despite implementation of several public health interventions for its control. Operational limitations and methodological gaps have been associated with malaria control interventions and research, and these have necessitated the need for a well-tailored Malaria Operational Research (MOR) agenda. However, there is paucity of evidence-based information on relevant stakeholders’ experience, awareness, perceptions and use of MOR and suggestions on setting MOR agenda. As part of a larger study to provide data for national MOR agenda setting, we assessed the MOR research situation from the perspectives of key stakeholders in Nigeria and contribution of MOR to the malaria elimination agenda</p><p>Methods</p><p>We conducted key informant interviews among 40 purposively selected stakeholders from the six geo-political zones in Nigeria. Data was collected using a pre-tested key informant interview guide which comprised issues related to experience, awareness, use of MOR and MOR needs, and suggestions for MOR. We conducted a detailed content analysis.</p><p>Results</p><p>Half of the participants had participated in MOR. Participants perceived MOR as important. Only few were aware of existing framework for MOR in Nigeria while above half expressed that MOR is yet to be used to inform policy in Nigeria. Participants identified several MOR needs such as development of improved diagnostic techniques, and interventions for promoting early diagnosis, prompt treatment and quality programmatic data. Participants opined the need for country-specific prioritised MOR agenda that cut across malaria thematic areas including malaria prevention and case management. Participants suggested the involvement of various stakeholders and multi-disciplinary approach in setting MOR.</p><p>Conclusion</p><p>Although some stakeholders have been involved in MOR, it is still rarely used to inform policy and several needs exist across thematic areas. A broad-based stakeholder involvement, multi-disciplinary approach to agenda setting and its wide dissemination have been suggested.</p></div

Diurnal rhythm of blood pressure among Nigerians with hypertension using 24-hour ambulatory blood pressure monitoring

Introduction:&nbsp;hypertension is the most common cardiac disease in Nigeria. There are very limited studies in Nigeria on the use of 24-hour ambulatory blood pressure monitoring (24-h ABPM) for evaluation of hypertensive patients. Twenty four-hour ABPM, unlike office blood pressure (OBP), can assess diurnal variation using parameters like awake blood pressure (BP), asleep (nocturnal) BP, mean 24-hour BP and dipping pattern. This can help in assessment of increased cardiovascular risk and management of hypertensive patients. We purposed to assess the diurnal rhythm of BP among Nigerians with hypertension. Methods:&nbsp;this was a prospective cross-sectional study. Consecutive 77 hypertensive subjects were studied using Schiller MT-300 for 24-h ABPM. Results:&nbsp;out of the 77 patients reviewed, 39 (50.6%) were females. The mean age was 50.9 years (SD 13.5). The mean awake systolic and diastolic BP were 135.6mmHg (SD 15.0) and 83.2mmHg (SD 10.0) respectively; mean asleep systolic and diastolic BP were 127.6mmHg (SD 17.9) and 76.2mmHg (SD 12.2) respectively; and mean 24-h systolic and diastolic BP were 133.6mmHg (SD 15.3) and 81.4mmHg (SD 10.2) respectively. Awake BP was elevated in 59.7% of study subjects. Elevated awake systolic BP and awake diastolic BP were present in 50.6% and 41.6% of the study population. Nocturnal (asleep) BP was elevated in 79.2%. Non-dipping pattern was the most prevalent pattern at 55.8%, followed by dipping (24.7%), reverse dipping (15.6%) and extreme dipping (3.9%). Conclusion:&nbsp;a high proportion had nocturnal hypertension (79.2%) and non-dipping pattern was the most prevalent pattern (55.8%). Mean awake systolic BP, mean asleep systolic and diastolic BP and mean 24-h systolic and diastolic BP were elevated. The use of 24-h ABPM will enhance assessment of increased cardiovascular risk and management of Nigerians with hypertension