Occurrence and recalcitrance of polyethylene bag waste in Nigerian soils

Attempts to biodegrade polyethylene bag wastes (pure water sachets) weighing 25.2 g each were made by burying them in the soil and subjecting them to acid treatment (0.5 M HNO3) and alkaline treatment (0.5 M NaOH) over a 24 week study period. The experimental polyethylene bags (ED1) were inoculated with a strain of Pseudomonas spp. isolated from a refuse dump and by inorganic nutrient supplementation to facilitate biodegradation. Samples without inorganic nutrient supplementation and Pseudomonas spp. inoculation served as first control (CD1), while those placed on a slab on the surface of the soil served as second control (CD2) to evaluate the roles played by microorganisms and physical degradation, respectively. ED1 showed a slight reduction in weight to 24.9 g at week 16 after the acid treatment for 5 days and further reduced to 24.7 g at the end of the study after the alkaline treatment. CD1 reflected no variations in weight, while CD2 reduced to 25.1 g. The study showed that recycling of used pure water sachets which yielded useful products such as water seal, polyethylene bags and jerry can covers, appears to be the only option of checking environmental pollution caused by this product as microbial degradation proved ineffective.Key words: Biodegradation, polyethylene, waste, recycling, recalcitrance

Microbial Profile, Antibacterial and Antioxidant Activities of some Imported Spices in Nigeria

Spices are commonly used in most Nigerian dishes as flavour and colour enhancer, nutrient supplements or to serve as preservatives, medicine and as part of cultural inclinations. They are naturally of plant parts and in recent times, certain synthetic creations of flavorists have found use in food as flavour and colour enhancers. The upsurge in quest for dishes of other cultures, and for food containing plant products deemed to have antioxidant properties have resulted in large import of different spices into the Nigerian market. This study was conducted to determine the microbial profile, antibacterial and antioxidant activities of some imported spices in Nigerian market. Fifteen each, of five different brands of imported spices packaged in polyethylene containers were purchased from supermarkets in different regions of Nigeria. The mean (cfu/g) total aerobic plate counts in the samples range from 1.8 x103 to 7.0x104, Coliform count was 1.1x102 to 4.1x103 and mean fungi count was 1.0x101 to 2.9x103. Microorganisms isolated from some of the spices include spp of Bacillus, Staphylococcus, Proteus, Enterobacter, Pseudomonas, Aspergillus, Rhizopus and Fusarium. Some of the spices had antimicrobial effects on the clinical isolates tested with MIC ranging from 6.25 to 25.0 mg/ml. The spices contain Phenolics and flavonoids and have DPPH, Hydrogen peroxide and Nitric oxide scavenging activities. Adequate HACCP evaluation and GMP in the processing of spices is advanced, further studies are necessary to harness the full antimicrobial and antioxidant activities of these spices for therapeutic purpose

Improving the Drug Bioavailability Property of Myricetin through a Structural Monosubstitution Modification Approach: an In-Silico Pharmacokinetics Study

Myricetin belongs to the members of polyphenolic compounds that make up the flavonoid class, which possess antioxidant properties. Myricetin is mostly obtained from vegetables, fruits, nuts, berries, tea, and is also found in red wine. It is also similar structurally to quercetin, fisetin and luteolin and is known to possess similar functions as the other members in the flavonol class of flavonoids. The health benefits of myricetin cuts across being an anticarcinogen compound to its antiviral, antithrombotic, antidiabetic, antiatherosclerotic, neuroprotective and anti-inflammatory properties among others. It also plays a role as a cyclooxygenase 1 inhibitor, an antineoplastic agent, an antioxidant, a plant metabolite, a food component and a hypoglycemic agent. It is a hexahydroxyflavone and a 7-hydroxyflavonol. The 2D structure of myricetin was obtained from the PubChem database while the MarvinSketch software was used to effect the various structural modifications on the compound. The structural modifications entails the substitution of the OH group attached to the C1 of myricetin with different functional groups such as the C=O, C2H5, CH3, CHO, CONH2, H and OCH3 which were saved as mrv files. The saved mrv files for each 2D structures were converted into canonical SMILES with the aid of the Open Babel software while the pharmacokinetic parameters for each compound was predicted using the SwissADME server. Results from this study showed that the C2H5, CH3 and H analogues of myricetin showed a higher gastrointestinal absorption rate compared to their C=O, CHO, CONH2 and OCH3 counterparts. This result shows that the C2H5, CH3 and H analogues of myricetin might be more orally bioavailable compared to myricetin and the other modified analogues. Preclinical studies on these compounds are therefore recommende

Strength Variation of OPC-Saw Dust Ash Composites with Percentage Saw Dust Ash

This work investigated the variation of OPC-Saw Dust Ash (SDA) composites strength with percentage SDA. 231 concrete cubes, 231 sandcrete cubes, and 231 soilcrete cubes of 150mm x 150mm x 150mm were produced at percentage OPC replacement with SDA of 0% (control), 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, and 50% and crushed to obtain their compressive strengths at 3, 7, 14, 21, 28, 50, and 90 days of curing. For concrete, the 90-day strength values decreased from 28.00N/mm2 at 5% SDA to 25.60N/mm2 at 15% SDA to 20.50N/mm2 at 35% SDA to 15.80N/mm2 at 50% SDA, while the control value was 27.00N/mm2. The 90-day strength values also decreased from 11.50N/mm2 at 5% SDA to 5.40N/mm2 at 50% SDA for sandcrete while the control value was 11.10N/mm2. Soilcrete strength values decreased from 9.70N/mm2 at 5% SDA to 4.50N/mm2 at 50% SDA while the control value was 9.50N/mm2. The results suggest that, with good quality control of the concreting process, 5% to 25% OPC replacement with SDA could be suitable for general reinforced concrete works, 25% to 40% for minor works in concrete, and 45% to 50% for plain concrete works. Also, 5% to 20% OPC replacement with SDA could be used for light load-bearing sandcrete and soilcrete works, while 25% to 50% could still be suitable for non-load-bearing works. Keywords: Blended cement, Composites, Compressive strength, Concrete, Sandcrete, Saw dust ash, Soilcrete

Patient characteristics associated with COVID-19 positivity and fatality in Nigeria: retrospective cohort study

Objective: Despite the increasing disease burden, there is a dearth of context-specific evidence on the risk factors for COVID-19 positivity and subsequent death in Nigeria. Thus, the study objective was to identify context-specific factors associated with testing positive for COVID-19 and fatality in Nigeria. Design Retrospective cohort study. Setting: COVID-19 surveillance and laboratory centres in 36 states and the Federal Capital Territory reporting data to the Nigeria Centre for Disease Control. Participants: Individuals who were investigated for SARSCoV-2 using real-time PCR testing during the study period 27 February–8 June 2020. Methods: COVID-19 positivity and subsequent mortality. Multivariable logistic regression analyses were performed to identify factors independently associated with both outcome variables, and findings are presented as adjusted ORs (aORs) and 95% CIs. Results: A total of 36 496 patients were tested for COVID-19, with 10 517 confirmed cases. Of 3215 confirmed cases with available clinical outcomes, 295 died. Factors independently associated with COVID-19 positivity were older age (p value for trend<0.0001), male sex (aOR 1.11, 95%CI 1.04 to 1.18) and the following presenting symptoms: cough (aOR 1.23, 95% CI 1.13 to 1.32), fever (aOR 1.45, 95% CI 1.45 to 1.71), loss of smell (aOR 7.78, 95% CI 5.19 to 11.66) and loss of taste (aOR 2.50, 95% CI 1.60 to 3.90). An increased risk of mortality following COVID-19 was observed in those aged ≥51 years, patients in farming occupation (aOR 7.56, 95% CI 1.70 to 33.53) and those presenting with cough (aOR 2.06, 95% CI 1.41 to 3.01), breathing difficulties (aOR 5.68, 95% CI 3.77 to 8.58) and vomiting (aOR 2.54, 95% CI 1.33 to 4.84). Conclusion: The significant risk factors associated with COVID-19 positivity and subsequent mortality in the Nigerian population are similar to those reported in studies from other countries and should guide clinical decisions for COVID-19 testing and specialist care referrals

Pneumococcal carriage in sub-Saharan Africa--a systematic review.

BACKGROUND: Pneumococcal epidemiology varies geographically and few data are available from the African continent. We assess pneumococcal carriage from studies conducted in sub-Saharan Africa (sSA) before and after the pneumococcal conjugate vaccine (PCV) era. METHODS: A search for pneumococcal carriage studies published before 2012 was conducted to describe carriage in sSA. The review also describes pneumococcal serotypes and assesses the impact of vaccination on carriage in this region. RESULTS: Fifty-seven studies were included in this review with the majority (40.3%) from South Africa. There was considerable variability in the prevalence of carriage between studies (I-squared statistic = 99%). Carriage was higher in children and decreased with increasing age, 63.2% (95% CI: 55.6-70.8) in children less than 5 years, 42.6% (95% CI: 29.9-55.4) in children 5-15 years and 28.0% (95% CI: 19.0-37.0) in adults older than 15 years. There was no difference in the prevalence of carriage between males and females in 9/11 studies. Serotypes 19F, 6B, 6A, 14 and 23F were the five most common isolates. A meta-analysis of four randomized trials of PCV vaccination in children aged 9-24 months showed that carriage of vaccine type (VT) serotypes decreased with PCV vaccination; however, overall carriage remained the same because of a concomitant increase in non-vaccine type (NVT) serotypes. CONCLUSION: Pneumococcal carriage is generally high in the African continent, particularly in young children. The five most common serotypes in sSA are among the top seven serotypes that cause invasive pneumococcal disease in children globally. These serotypes are covered by the two PCVs recommended for routine childhood immunization by the WHO. The distribution of serotypes found in the nasopharynx is altered by PCV vaccination