Senegalia Senegal response to inoculation with rhizobial strains vary in relation to seed provenance and soil type

Aims: The focus of the study was to determine the symbiotic and growth response of three Senegalia Senegal (Syn. Acacia Senegal, gum arabic tree) provenances, namely Dahra (Senegal), Tera (Niger) and Makueni (Kenya) to inoculation with selected S. Senegal-nodulating rhizobia in soils from Dahra and Goudiry regions of Senegal, representing typical soil and enviromental conditions for establishing gum arabic production plantations. Methods: A greenhouse experiment was performed to evaluate the effect of 11 rhizobial strains on nodulation and growth of three S. Senegal provenances in two field soils, differing in nutrient status and indigenous rhizobia. After 4 months, plants were harvested for determination of nodulation, shoot and root dryweight. Results: Nodulation and growth of S. Senegal varied in relation to rhizobial strain, provenance, soil type, and their interactions. Generally, nodulation was higher in Dahra than Goudiry soils, while Makueni provenance was the most compatible host. Inoculation had a significant effect on all parameters measured in Dahra field soil. By contrast, inoculation had a significant effect on height (shoot length), and shoot, root and total dry matter but not on nodulation. In the two field soils, seed provenance effect was significant for all parameters measured. The interaction between inoculation and provenance showed a significant effect on all parameters measured except nodule number in Dahra field soil while in Goudiry, the interaction had a significant effect on seedling height and shoot, root, and total dry matter but this effect was not significant with nodulation parameters. Conclusions: S. Senegal is variable in its response to inoculation, it is therefore advantageous to select and match effective rhizobia-provenance symbionts for each site

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research

Level of agreement between objectively determined body composition and perceived body image in 6- To 8-year-old South African children- To Body Composition-Isotope Technique study

To assess the level of agreement between body size self-perception and actual body size determined by body mass index (BMI) z-score and body fatness measured by the deuterium dilution method (DDM) in South African children aged 6-8 years. A cross-sectional sample of 202 children (83 boys and 119 girls) aged 6-8 years from the Body Composition-Isotope Technique study (BC-IT) was taken. Subjective measures of body image (silhouettes) were compared with the objective measures of BMI z-score and body fatness measured by the DDM. The World Health Organization BMI z-scores were used to classify the children as underweight, normal, overweight, or obese. DDM-measured fatness was classified based on the McCarthy centile curves set at 2nd, 85th and 95th in conjunction with fatness cut-off points of 25% in boys and 30% in girls. Data were analyzed using SPSS v26. Of 202 children, 32.2%, 55.1%, 8.8%, and 2.4% perceived their body size as underweight, normal, overweight, and obese, respectively. Based on BMI z-score, 18.8%, 72.8%, 6.9%, and 1.5% were classified as underweight, normal, overweight, and obese, respectively. Body fatness measurement showed that 2.5%, 48.0%, 21.8%, and 29.7% were underweight, normal weight, overweight, and obese, respectively

Modelling livestock test-and-treat: a novel One Health strategy to control schistosomiasis and mitigate drug resistance

Schistosomiasis, a neglected tropical disease, is a widespread chronic helminthiasis reported in 78 countries, predominantly those within sub-Saharan Africa, as well as Latin America, Asia, and most recently, even Europe. Species of the causative blood fluke infect not only humans but also animals, and hybrids between previously assumed human-specific and animal-specific schistosomes are being increasingly reported. Existing control programs across Africa focus on humans and rely heavily on mass drug administration of praziquantel, the sole drug available against schistosomiasis. Praziquantel is safe and highly efficacious but could become ineffective if resistance emerges. To reach the revised World Health Organization goal of elimination of schistosomiasis as a public health problem, and interruption of transmission within selected regions, by 2030, new consideration of the role of animal reservoirs in human transmission in general, and whether to also treat livestock with praziquantel in particular, has been raised. However, whilst there are no dedicated control programs targeting animals outside of Asia, there are emerging reports of the use and misuse of praziquantel in livestock across Africa. Therefore, to effectively treat livestock in Africa and to help mitigate against the potential evolution of praziquantel resistance, structured control strategies are required. Here, using a transmission modelling approach, we evaluate the potential effectiveness of a theoretical test-and-treat (TnT) strategy to control bovine schistosomiasis using a currently available point-of-care diagnostic test (developed for human use) to detect circulating cathodic antigen (POC-CCA). We show that implementing TnT at herd-level from 2022 to 2030 could be highly effective in suppressing infection in cattle and even, in lower prevalence settings, reaching nominal ‘elimination’ targets. We highlight the importance of enhancing the specificity of POC-CCA for use in livestock to avoid unnecessary treatments and discuss the outstanding challenges associated with implementing TnT as part of a holistic One Health approach to tackling human and animal schistosomiasis

Halotolerant aminopeptidase M29 from Mesorhizobium SEMIA 3007 with biotechnological potential and its impact on biofilm synthesis

Abstract The aminopeptidase gene from Mesorhizobium SEMIA3007 was cloned and overexpressed in Escherichia coli. The enzyme called MesoAmp exhibited optimum activity at pH 8.5 and 45 °C and was strongly activated by Co2+ and Mn2+. Under these reaction conditions, the enzyme displayed Km and kcat values of 0.2364 ± 0.018 mM and 712.1 ± 88.12 s−1, respectively. Additionally, the enzyme showed remarkable stability in organic solvents and was active at high concentrations of NaCl, suggesting that the enzyme might be suitable for use in biotechnology. MesoAmp is responsible for 40% of the organism’s aminopeptidase activity. However, the enzyme’s absence does not affect bacterial growth in synthetic broth, although it interfered with biofilm synthesis and osmoregulation. To the best of our knowledge, this report describes the first detailed characterization of aminopeptidase from Mesorhizobium and suggests its importance in biofilm formation and osmotic stress tolerance. In summary, this work lays the foundation for potential biotechnological applications and/or the development of environmentally friendly technologies and describes the first solvent- and halo-tolerant aminopeptidases identified from the Mesorhizobium genus and its importance in bacterial metabolism