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IntroductionRhizosphere bacterial communities play a crucial role in promoting plant and soil ecosystem health and productivity. They also have great potential as key indicators of soil health in agroecosystems. Various environmental factors affect soil parameters, which have been demonstrated to influence soil microbial growth and activities. Thus, this study investigated how rhizosphere bacterial community structure and functions are affected by agronomic practices such as organic and conventional fertiliser application and plant species types.MethodsRhizosphere soil of vegetable crops cultivated under organic and conventional fertilisers in different farms was analysed using high-throughput sequencing of the 16S rRNA gene and co-occurrence network pattern among bacterial species. The functional structure was analysed with PICRUSt2 pipeline.ResultsOverall, rhizosphere bacterial communities varied in response to fertiliser type, with soil physicochemical parameters, including NH4, PO4, pH and moisture content largely driving the variations across the farms. Organic farms had a higher diversity richness and more unique amplicon sequence variants than conventional farms. Bacterial community structure in multivariate space was highly differentiated across the farms and between organic and conventional farms. Co-occurrence network patterns showed community segmentation for both farms, with keystone taxa more prevalent in organic than conventional farms.DiscussionModule hub composition and identity varied, signifying differences in keystone taxa across the farms and positive correlations between changes in microbial composition and ecosystem functions. The organic farms comprised functionally versatile communities characterised by plant growth-promoting keystone genera, such as Agromyces, Bacillus and Nocardioides. The results revealed that organic fertilisers support high functional diversity and stronger interactions within the rhizosphere bacterial community. This study provided useful information about the overall changes in soil microbial dynamics and how the changes influence ecosystem functioning under different soil nutrient management and agronomic practices.

Abstract Aloe species are often used interchangeably for medicinal and cosmeceutical applications, presenting a challenge to the biological efficacy consistency of some herbal preparations. Sustainable production of high-quality commonly used medicinal plants remains a limitation for commercialisation. Thus, this study investigated the potential for plant substitution by examining bacterial endophytes capable of producing similar host plant secondary metabolites. The metabolite profiles and endophytic bacterial communities of endangered Aloe lettyae were compared with those of Aloe longibracteata using nuclear magnetic resonance spectroscopy and 16 S rRNA gene sequencing. Only 15 metabolites were significantly different between A. lettyae and A. longibracteata based on metabolite concentrations. However, both plants’ functionality and potential application remain comparable. Phytohormones, including indole-3-acetate and 5-hydroxyindole-3-acetate, were more concentrated in A. lettyae than A. longibracteata. Metabolites such as tyrosine, allantoin, and myo-inositol, with human health benefits, were annotated in both species. Aloe lettyae harboured a phylogenetically diverse bacteria community compared to A. longibracteata, with a higher richness of bacterial species, indicating a likelihood of diverse metabolic capabilities among the bacteria. Dominant endophytes, including Bacillus, Comamonas, and Pseudomonas, possess enzymes contributing to various metabolic pathways. The enzymes have the potential to impact the synthesis, or breakdown of plant metabolites, consequently influencing the overall metabolic composition of the host plant. Therefore, this study supports the interchangeability of A. lettyae and A. longibracteata due to their ability to produce similar metabolites, and although the Aloe species exhibit phylogenetically diverse endophytic communities, the feasibility of utilizing their endophytes as producers of secondary metabolites remains viable. Graphical abstract

Cancer poses a significant global health challenge, with 10 million deaths and 19.3 million new cases reported annually. This review aims to investigate the emerging field of synbiotics and their potential to enhance the effectiveness of cancer therapies. By conducting a thorough analysis of preclinical and clinical studies, this review clarifies the various mechanisms through which synbiotics improve the efficacy of conventional cancer treatments, such as chemotherapy, immunotherapy, surgery, and radiotherapy. A search of literature on the anti-cancer efficacy of synbiotics was performed using the PubMed database and Google Scholar search engine to find important original research and review publications. A selection, analysis, and discussion of related English-language papers were conducted. This review unravels the intricate connections between microbiota and cancer therapeutics, harnessing the power of synbiotics as a promising strategy to improve treatment outcomes and elevate the standard of care in oncology. Further research is required to establish the efficacy and long-term safety of synbiotics, the ideal prebiotic-probiotic combinations, and the distinct microbiota signatures of different cancer types for the development of future synbiotics.

Dynamic multi-objective optimization problems (DMOPs) are optimization problems where elements of the problems, such as the objective functions and/or constraints, change with time. These problems are characterized by two or more objective functions, where at least two objective functions are in conflict with one another. When solving real-world problems, the incorporation of human decision-makers (DMs)’ preferences or expert knowledge into the optimization process and thereby restricting the search to a specific region of the Pareto-optimal Front (POF) may result in more preferred or suitable solutions. This study proposes approaches that enable DMs to influence the search process with their preferences by reformulating the optimization problems as constrained problems. The subsequent constrained problems are solved using various constraint handling approaches, such as the penalization of infeasible solutions and the restriction of the search to the feasible region of the search space. The proposed constraint handling approaches are compared by incorporating the approaches into a differential evolution (DE) algorithm and measuring the algorithm’s performance using both standard performance measures for dynamic multi-objective optimization (DMOO), as well as newly proposed measures for constrained DMOPs. The new measures indicate how well an algorithm was able to find solutions in the objective space that best reflect the DM’s preferences and the Pareto-optimality goal of dynamic multi-objective optimization algorithms (DMOAs). The results indicate that the constraint handling approaches are effective in finding Pareto-optimal solutions that satisfy the preference constraints of a DM.

Presently, the global biofertilizer market is expanding due to the rising acceptance of efficient soil nutrient management practices such as the application of biofertilizers amongst farmers. Biofertilizers are preferred to chemical fertilizers because they are cost-effective, ecologically friendly, and guarantee sustainable agricultural production. However, the biofertilizer industry is underdeveloped in many African countries due to several challenges; thus, the full adoption and benefits of biofertilizer are yet to be fully realized compared to the developed nations. Therefore, the present review describes the production, usage, challenges as well as the strategies and opportunities for the development of biofertilizer in Africa. The findings show that inadequate biofertilizer research, lack of technology development, and ineffective regulatory framework have largely contributed to the challenges of biofertilizer development in Africa. Although there is evidence of some form of regulations in some African nations, effective biofertilizer regulations and quality control management championed by the government would further promote the production of quality biofertilizers and usage amongst African farmers. Adequate and effective extension programs, agromarket development, as well as agricultural and research institution development, could improve the production and adoption of biofertilizers in Africa. To achieve increased commercial production and optimal application of biofertilizer amongst farmers in Africa, a deliberate intervention by African government through biofertilizer policy, funding and the development of efficient quality control system and market strategies is essential. More so, government and private sector participation in sustainable investment and technical support will lead to substantial biofertilizer commercialization and adoption in Africa.

This study investigated 13-commercial biofertilisers for their microbial contents and potential functional capabilities using a culture-based approach. Isolates obtained were identified by sequencing the partial I6S rRNA gene and ITS 1 and 2 regions and screened for plant growth-promoting capabilities. A total of 58 bacterial and three fungal isolates were obtained from all biofertilisers, with major genera being Bacillus, Rhizobium, Pseudomonas, Candida and Aspergillus. Five of the biofertilisers had the microbes (all or some) listed in the label detected while eight products had none detected. All the products had more microbes than that declared in the labels, suggesting the presence of potential contaminants. Generally, all the identified microbes, including the potential contaminants, had different beneficial capabilities. Approximately 40% of the isolates showed potential for nitrogen-fixation, while 27% exhibited high phosphate-solubilisation ability. Additionally, 87% of the isolates produced indole acetic acid in the range of 0.1–114.4 μg/mL. High levels of siderophore production were mainly observed amongst Bacillus and Pseudomonas genera. The potential of the microbes, including those not listed in the label, to fix nitrogen and produce acid phosphatase, indole acetic acid and siderophore, was highest in four products. This suggests the products have multiple functional abilities in improving crop productivity. However, other qualities of biofertiliser, such as viable cell count and level of contamination, must always be within the acceptable standards. This will guarantee high product quality as well as efficiency when applied in the field. Overall, the results show that there is a high correlation between microbial compositions and potential capability of biofertilisers for plant-growth promotion.

Background and Objective: The recent trend in cataract surgery is the use of regional ophthalmic nerve blocks or topical anesthesia. We determined and compared the effect of peribulbar and subtenon block on pain and patients' satisfaction, following small incision cataract surgery (SICS). Methods: This was age-sex-matched comparative study involving 462 ASA I-III patients, aged 18 years and above scheduled for SICS. They were assigned to receive either peribulbar block (Group P) or subtenon (Group ST). The pain score and patients' satisfaction with the anesthetic experiences were recorded by a study-masked anesthesiologist during surgery and postoperatively at 30 min and 1, 2, 4, and 24 h. Results: The median numeric rating score was significantly lower in the subtenon group than the peribulbar group: During surgery, Group ST 1 (1) versus group P 1.5 (2.25), P < 0.001. At 30 min after surgery, Group ST 0 (1) versus Group P 1 (2.5) versus P < 0.001, and at 1 h after surgery, Group ST 0 (1) versus group P 1 (2), P = 0.002. Ten patients had akinesia in the peribulbar group compared with one in the subtenon group. Chemosis was significantly higher in the subtenon group 10 (3.2%) than in the peribulbar group 0 (0%), P = 0.035. Similarly, a significant difference was not with subconjuctival hemorrhage; subtenon 14 (4.5%) versus peribulbar 2 (1.3%), P = 0.105. Conclusion: The use of subtenon block resulted in lower pain scores and higher patient's satisfaction than peribulbar block. However, subconjuctival hemorrhage and chemosis were more common with subtenon block.

Background: Presbyopia is an age-related loss of lens accommodation resulting in difficulty in performing near task with attendant effect on the quality of life. Objective: The objective of the study was to determine the prevalence of presbyopia and presbyopic spectacle correction coverage among public school teachers in Ifo township, with a view to providing a baseline information that could be useful for advocacy and planning appropriate intervention. Study Design: The study was a descriptive, cross-sectional study. Materials and Methods: Six hundred public school teachers aged 30 years and above were examined in 25 clusters using a multistage random sampling technique with probability proportional to size. Questionnaire was used to obtain information on demographic data, sources of spectacle and barriers to spectacle use. All participants underwent a standardised protocol including visual acuity assessment (distance and near acuity), anterior and posterior segment examinations and refraction. Results: Six hundred teachers were examined with an age range of 30–61 years. The mean age was 44.7 ± 7.5 years and the male to female ratio was 1:2.2. The prevalence of presbyopia was 81.3% and 38.5% of the presbyopic teachers did not have presbyopic correction. However, the average age of onset of presbyopia was earlier in females 33 years compared to 36 years observed in males, although not statistically significant (P = 0.88). The presbyopic correction coverage was 61.5%. One hundred and eighty-six (62%) presbyopic teachers obtained their spectacle from opticians, and the main barriers to the use of near vision spectacle were lack of awareness (23.7%) and cost (13.7%). Conclusion: This study demonstrated a high prevalence of presbyopia among public school teachers in Ifo town, South-West Nigeria, but less presbyopic spectacle correction coverage.

Background: Destructive eye surgeries are terminal treatment modalities for some ophthalmic conditions with psychological, emotional and cosmetic implications, especially for the patients and their relatives. Objective: The aim of this study was to determine the frequency and indications for destructive eye surgeries at an Eye Centre of a Nigerian Tertiary Hospital with a view to identifying the preventable indications for which appropriate preventive measures could be recommended. Patients and Methods: A retrospective, descriptive study of all patients who underwent evisceration, enucleation or exenteration at the Guinness Eye Centre, Lagos University Teaching Hospital from January 2003 to December 2012 was performed. Their outpatient, ward and theatre records were retrieved and reviewed. Information obtained included age, sex, eye affected, duration of symptoms before presentation, visual acuity of affected eye at diagnosis, indication for surgery and type of destructive surgery. Results: A total of 186 eyes of 185 patients were surgically removed constituting 4.8% of a total of 3866 surgeries performed during the period of study. Children below 16 years accounted for 33.5% of the cases while 30.3% were in their first decade of life. Overall, the most common indication for destructive eye surgery was trauma (36.2%) followed by tumour (27.6%) and ocular infection (18.4%). However, tumour (73.2%) was the most common indication in the first decade of life with retinoblastoma accounting for 92.7% of these. Conclusion: Ocular trauma, tumour and infection were the most common indications for destructive eye surgery in this centre.

Small incision cataract surgery (SICS) offers the benefits of a phacoemulsification (phaco) surgery without the attendant high cost, but it is not without certain risk such as nucleus drop into the vitreous as seen in phaco. A retrospective study of SICS and associated factors leading to nucleus drop during surgery, challenges of management and the visual outcomes. Of 793 eye surgeries performed during the study 586 were SICSs. Nucleus drop during SICS occurred in 0.68% of patients. Can-opener technique of capsulotomy, use of dispersive viscoelastic, diabetes mellitus, lack of anterior vitrectomy machine and poor access to immediate posterior vitrectomy were important problems in the management of the cases of nucleus drop in this study. The visual outcomes were poor in all the cases of nucleus drop. Careful patient selection for SICS and the use of continuous curvilinear capsulorhexis are advocated. An interior vitrectomy machine should be available to all cataract surgeons. It is good professional practice to be acquainted with the available vitreo-retina surgeons for urgent assistance in cases of nucleus drop.

Low fertility and inefficient management of sub-Saharan African soils have been the major challenges facing productivity among smallholder farmers. Unfortunately, inorganic fertiliser used as major soil nutrient management is unsustainable, causing soil degradation and environmental pollution. Therefore, smallholder farmers may only realise their maximum potential if a more sustainable, low-cost and efficient integrated nutrient management system compatible with their socioeconomic status is practised. Currently, the increasing demand for sustainable agriculture is driving the use of biological fertilisers, which are composed of beneficial microorganisms; ranging from bacteria to blue-green algae and fungi. Biofertilisers such as Rhizobium, Azotobacter, Azospirillum, Pseudomonas and Bacillus have invaluable use in sustainable agriculture owing to their environmentally-friendliness, cost-effectiveness and improved productivity benefits. They improve plant nutrition and yield through biological nitrogen fixation, nutrient solubilisation, biocontrol activities and production of plant growth promoting substances. This review specifically focuses on biofertiliser potential as an efficient integrated nutrient management in increasing smallholder farmer productivity and profitability. It also suggests that increasing biofertiliser awareness and use is an impetus for maintaining and improving ecological stability and alleviating poverty, especially among the rural dwellers. Importantly, efficient biofertiliser strategies by stakeholders will improve adoption of this technology among smallholder farmers. Subjects: Soil science; Microbiology; Biotechnology; Agricultural science

Background: . Up to 20% of people with HIV (PWH) who undergo virologically suppressed antiretroviral therapy (ART) fail to experience complete immune restoration. We recently reported that plasma anti-CD4 IgG (antiCD4IgG) autoantibodies from immune non-responders specifically deplete CD4 + T cells via antibody-dependent cytotoxicity. However, the mechanism of antiCD4IgG production remains unclear., Methods: . Blood samples were collected from 16 healthy individuals and 25 PWH on suppressive ART. IgG subclass, plasma lipopolysaccharide (LPS), and antiCD4IgG levels were measured by ELISA. Gene profiles in B cells were analyzed by microarray and quantitative PCR. Furthermore, a patient-derived antiCD4IgG-producing B cell line was generated and stimulated with LPS in vitro. B cell IgG class switch recombination (CSR) was evaluated in response to LPS in splenic B cells from C57/B6 mice in vitro., Results: . Increased plasma anti-CD4 IgGs in PWH were predominantly IgG1 and associated with increased plasma LPS levels as well as B cell expression of TLR2, TLR4, and MyD88 mRNA in vivo. Furthermore, LPS stimulation induced antiCD4IgG production in the antiCD4IgG B cell line in vitro. Finally, LPS promoted CSR in vitro., Conclusion: . Our findings suggest that persistent LPS translocation may promote anti-CD4 autoreactive B cell activation and antiCD4IgG production in PWH on ART, which may contribute to gradual CD4 + T cell depletion. This study suggests that reversing a compromised mucosal barrier could improve ART outcomes in PWH who fail to experience complete immune restoration., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Coronavirus disease 2019 (COVID-19) is associated with autoimmune features and autoantibody production in a small subset of the population. Pre-existing neutralizing antitype I interferons (IFNs) autoantibodies are related to the severity of COVID-19. Plasma levels of IgG and IgM against 12 viral antigens and 103 self-antigens were evaluated using an antibody protein array in patients with severe/critical or mild/moderate COVID-19 disease and uninfected controls. Patients exhibited increased IgGs against Severe acute respiratory syndrome coronavirus-2 proteins compared to controls, but no difference was observed in the two patient groups. 78% autoreactive IgGs and 93% autoreactive IgMs were increased in patients versus controls. There was no difference in the plasma levels of anti-type I IFN autoantibodies or neutralizing anti-type I IFN activity of plasma samples from the two patient groups. Increased anti-type I IFN IgGs were correlated with higher lymphocyte accounts, suggesting a role of nonpathogenic autoantibodies. Notably, among the 115 antibodies tested, only plasma levels of IgGs against human coronavirus (HCOV)-229E and HCOV-NL63 spike proteins were associated with mild disease outcome. COVID-19 was associated with a bystander polyclonal autoreactive B cell activation, but none of the autoantibody levels were linked to disease severity. Long-term humoral immunity against HCOV-22E and HCOV-NL63 spike protein was associated with mild disease outcome. Understanding the mechanism of life-threatening COVID-19 is critical to reducing mortality and morbidity., (© 2022 Wiley Periodicals LLC.)