Influence of spectral properties on cassava leaf development and metabolism

Cassava’s importance as a food security crop in Sub Saharan Africa will be enhanced by its special traits such as tolerance to drought and high yields under hydrothermal stress. Some of the special traits which include the light reflective and absorptive properties of the leaves that depend on the surface characteristics of the leaves, are variety dependent and may influence the plants’ reaction to light; hence, its photosynthetic capacity. We investigated the differences in the leaf spectral properties in different cassava varieties and related them to leaf biochemical properties using 20 cassava varieties established in a randomized complete block design in Kasese, western Uganda. Time dependent changes in leaf spectral characteristics were studied using Digimizer software and related to changes in sugar and pigment properties. Changes in the amount of reflected light were observed for the three main wavelengths used by plants (blue, green and red) with the blue being the most preferred. Total soluble free sugars exhibited a diurnal pattern from lower values (0.07 mg/g) after the dark period to higher values (0.313 mg/g) as the day progressed and was different from those of translocatable sugars such as sucrose. Chlorophyll a exhibited a curved pattern in all varieties increasing with increase in light intensity from 09:00 h (0.18 ug/g), peaking at 15:00 h (0.22 ug/g) and dropping down in concentration by 18:00 h (0.16 ug/g). Significant differences were observed in cassava varieties for the concentration of chlorophylls and carotenes. The results were obtained at a time of optimal growth conditions (four months after planting) and were used to classify these varieties into three broad groups showing that studies on spectral properties of leaves can still give a lot of insights in selection for stress tolerance under less optimal stress. The significant changes observed in the phenotype especially the foliar portion of the plant with the stay green and early recovering mechanisms of tolerance identified also tarried well with observed spectral differences. The results show that studies on plant spectral properties can be important in making inferences on the plants physiological and growth status.Keywords: Spectral properties, tolerance mechanisms, physiology, reflectance

Oesophageal cancer management guidelines for Uganda

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Drug procurement, the Global Fund and misguided competition policies

In an effort to increase competition and decrease price, the Global Fund to Fight AIDS, Tuberculosis and Malaria recently began asking some grant recipients to use international competitive bidding processes for certain drug purchases. Unfortunately, for countries like Kenya, this request has caused more harm than good. After awarding the tender for its annual supply of the anti-malarial artemether-lumefantrine to the lowest bidder, Ajanta Pharma, Kenya experienced wide stock-outs in part due to the company's inability to supply the order in full and on time. Similar problems could arise in Uganda. Despite Kenya's experience, Uganda has awarded its next tender for artemether-lumefantrine to Ajanta Pharma. Uganda is already facing wide stock-outs and risks exacerbating an already dire situation the longer it takes to fulfil the procurement contract. A tender process based primarily on price cannot account for a company's ability to consistently supply sufficient product in time

Diurnal oscillation of SBE expression in sorghum endosperm

Spatial and temporal expression patterns of the sorghum SBEI, SBEIIA and SBEIIB genes, encoding, respectively, starch branching enzyme (SBE) I, IIA and IIB, in the developing endosperm of sorghum (Sorghum bicolor) were studied. Full-length genomic and cDNA clones for sorghum was cloned and the SBEIIA cDNA was used together with gene-specific probes for sorghum SBEIIB and SBEI. In contrast to sorghum SBEIIB, which was expressed primarily in endosperm and embryo, SBEIIA was expressed also in vegetative tissues. All three genes shared a similar temporal expression profile during endosperm development, with a maximum activity at 15-24 days after pollination. This is different from barley and maize where SBEI gene activity showed a significantly later onset compared to that of SBEIIA and SBEIIB. Expression of the three SBE genes in the sorghum endosperm exhibited a diurnal rhythm during a 24-h cycle

In vitro embryo rescue and plant regeneration following self-pollination with irradiated pollen in cassava (Manihot esculenta Crantz)

Cassava is a highly heterozygous species; hence, current methods used in classical cassava breedingcannot match the urgent need to high yielding varieties. Recently, progress was made through androgenesis and gynogenesis as pathways for raising doubled cassava haploid lines to overcome problems associated with cassava’s inherent reproductive biology, but these efforts were limited (nocandidate cassava plantlets were regenerated). For the first time, this study shows that pollen irradiation coupled with self-pollination and embryo rescue regenerated 62 candidate cassava plantlets. Plants of an elite cassava variety, Nase14, served as a mother plant and as the pollen donor for the irradiation. Irradiation dosages of 50 to 250 Gray studied across five pollination events and 300 or 500 Gray in one pollination event caused a reduction in pollen germination up to 67.0%. By 15 days after pollination (DAP) with irradiated pollen, up to 89.7% of the pollinated flowers had aborted. By embryo rescue time (42 DAP), significant differences were observed in number of fruits, seeds and embryos generated, with the non-irradiated pollen treatments having significantly higher numbers. Sixteen (16) heterozygous SSR markers in the parent and ploidy analysis showed that none of the regenerated plants was haploid or homozygous. However, the plantlets resulting from pollination with non-irradiated pollen had 56.2% homozygous loci, while progeny derived from irradiated treatments had frequencies of homozygous loci between 28.1 and 55.0%. This is the first time to use irradiated pollen in cassava as a pathway to generate candidate plantlets as an initial step in double haploid production.Key words: Cassava, doubled haploids, embryo rescue, plant regeneration, pollen germination, pollenirradiation

Laboratory Diagnosis of Candidiasis

The burden of Candidiasis continues to increase and so does the Candida species. Although Candida species are closely similar phenotypically, they differ from each other in terms of epidemiology, genetic characteristics, antifungal susceptibility and virulence profile. Therefore, reliable and accurate laboratory methods for identification of Candida species can determine the Candidiasis burden and enable the administration of the most appropriate antifungal drug therapy to reduce fungal mortality rates. Conventional and biochemical methods are often used in identification of Candida species. However, these techniques are specific and sensitive enough in detecting the non albicans candida (NAC) species. Molecular techniques have improved the laboratory diagnosis and management of Candidiasis due to improved sensitivity and specificity threshold. This chapter provides an overview of different laboratory methods for diagnosis of Candidiasis

Adverse Childhood Experiences and Adult Cardiometabolic Risk Factors and Disease Outcomes: Cross-Sectional, Populationbased Study of Adults in Rural Uganda

Background: Cardiovascular diseases (CVD) pose a major threat to public health in sub-Saharan African communities, where the burden of these classes of illnesses is expected to double by 2030. Growing research suggests that past developmental experiences and early life conditions may also elevate CVD risk throughout the life course. Greater childhood stress and adversity are consistently associated with a range of adult CVDs and associated risk factors, yet little research exists on the long-term effects of early life stress on adult physical health outcomes, especially CVD risk, in sub-Saharan African contexts. This study aims to evaluate the associations between adverse childhood experiences and adult cardiometabolic risk factors and health outcomes in a population-based study of adults living in Mbarara, a rural region of southwestern Uganda. Methods Data come from an ongoing, whole-population social network cohort study of adults living in the eight villages of Nyakabare Parish, Mbarara. A modified version of the Adverse Childhood Experiences-International Questionnaire (ACEs) assessed past exposure to physical, emotional, and sexual adversity. Participants also took part in a health fair where medical histories on cardiometabolic risk factors and cardiovascular diseases were gathered. Multiple logistic regression models estimated the associations between ACEs and cardiometabolic risk factors and health outcomes. Results Data were available on 545 adults. The average number of ACEs was 4.9 out of a possible 16. The cumulative number of ACEs were associated with having a history of heart attack and/or heart failure (adjusted odds ratio (AOR) = 1.11, 95% confidence interval (CI) = 0.999-1.234, P = 0.051), but the estimated association was not statistically significant. ACEs did not have statistically significant associations with any others measures of adult cardiometabolic risk and CVD. Conclusions: Adverse childhood experiences are not associated with a range of adult cardiometabolic risk factors and health outcomes in this sample of rural Ugandan adults. Further research in this sample is necessary to identify the pathways that may motivate these null relationship and possibly protect against adverse cardiometabolic and cardiovascular health outcomes

Alternative splicing and differential subcellular localization of the rat FGF antisense gene product

<p>Abstract</p> <p>Background</p> <p>GFG/NUDT is a nudix hydrolase originally identified as the product of the fibroblast growth factor-2 antisense (FGF-AS) gene. While the FGF-AS RNA has been implicated as an antisense regulator of FGF-2 expression, the expression and function of the encoded GFG protein is largely unknown. Alternative splicing of the primary FGF-AS mRNA transcript predicts multiple GFG isoforms in many species including rat. In the present study we focused on elucidating the expression and subcellular distribution of alternatively spliced rat GFG isoforms.</p> <p>Results</p> <p>RT-PCR and immunohistochemistry revealed tissue-specific GFG mRNA isoform expression and subcellular distribution of GFG immunoreactivity in cytoplasm and nuclei of a wide range of normal rat tissues. FGF-2 and GFG immunoreactivity were co-localized in some, but not all, tissues examined. Computational analysis identified a mitochondrial targeting sequence (MTS) in the N-terminus of three previously described rGFG isoforms. Confocal laser scanning microscopy and subcellular fractionation analysis revealed that all rGFG isoforms bearing the MTS were specifically targeted to mitochondria whereas isoforms and deletion mutants lacking the MTS were localized in the cytoplasm and nucleus. Mutation and deletion analysis confirmed that the predicted MTS was necessary and sufficient for mitochondrial compartmentalization.</p> <p>Conclusion</p> <p>Previous findings strongly support a role for the FGF antisense RNA as a regulator of FGF2 expression. The present study demonstrates that the antisense RNA itself is translated, and that protein isoforms resulting form alternative RNA splicing are sorted to different subcellular compartments. FGF-2 and its antisense protein are co-expressed in many tissues and in some cases in the same cells. The strong conservation of sequence and genomic organization across animal species suggests important functional significance to the physical association of these transcript pairs.</p

Maternal participation in a nutrition education program in Uganda is associated with improved infant and young child feeding practices and feeding knowledge: a post-program comparison study

Abstract Background Cost-effective approaches to improve feeding practices and to reduce undernutrition are needed in low-income countries. Strategies such as nutritional counseling, food supplements, and cash transfers can substantially reduce undernutrition among food-insecure populations. Lipid-based nutrient supplements (LNS) are an increasingly popular strategy for treating and preventing undernutrition and are often delivered with nutrition education. The post-program effects of participation in a LNS-supported supplemental feeding program on Infant and Young Child Feeding (IYCF) practices and caregiver child feeding knowledge are not well understood. The objective of this study was to understand whether children’s diet quality and caregiver nutrition knowledge was improved after participation in such a program. Methods We conducted a post-program comparison group study to compare feeding practices and caregiver nutrition knowledge among mother-child dyads who completed a nutrition education program and a community comparison group in western Uganda. We administered a feeding practices survey and two 24-h dietary recalls to 61 Post-Program (PP) caregivers and children ages 6 to 59 months (mean age = 25.1 months) who participated in a supplemental feeding program (which included growth monitoring, caregiver nutrition education, and LNS) and a Comparison Group (CG) of 61 children and caregivers. PP caregivers were recruited 4 to 8 weeks after program participation ended. We hypothesized that PP caregivers would report better IYCF practices and greater knowledge of key nutrition education messages related to IYCF. Results PP children had higher dietary diversity scores (3.0 vs 2.1, p =0.001) than CG children, and were more fed more frequently (3.0 vs 2.1 times per day, p = 0.001). IYCF indicators were higher in the PP group for minimum meal frequency (44.8% vs. 37.9%), minimum dietary diversity (10.3 vs. 3.4%), iron-rich complementary foods (17.2 vs. 20.7%), and minimally acceptable diet (10.3% vs 3.6%), but differences were non-significant. Caregivers in the PP group demonstrated greater knowledge of healthful IYCF practices. Conclusions Nutrition education can be effective to improve caregiver feeding practices and children’s dietary diversity and the frequency by which they are fed. A 10-week nutrition education and supplemental feeding program appears to provide some benefit to children in terms of dietary diversity and frequency of meals, and caregiver knowledge of feeding 1 to 2 months after program completion. However, children in this rural Ugandan region have diets that are still largely inadequate, highlighting the need for enhanced interventions and policies to promote diverse and appropriate diets for young children in this region. Future follow-up work in LNS-supported programs is recommended to understand how other similar approaches influence children's diet quality after program completion in other contexts

Multinational data show that conspiracy beliefs are associated with the perception (and reality) of poor national economic performance

While a great deal is known about the individual difference factors associated with conspiracy beliefs, much less is known about the country-level factors that shape people's willingness to believe conspiracy theories. In the current article we discuss the possibility that willingness to believe conspiracy theories might be shaped by the perception (and reality) of poor economic performance at the national level. To test this notion, we surveyed 6723 participants from 36 countries. In line with predictions, propensity to believe conspiracy theories was negatively associated with perceptions of current and future national economic vitality. Furthermore, countries with higher GDP per capita tended to have lower belief in conspiracy theories. The data suggest that conspiracy beliefs are not just caused by intrapsychic factors but are also shaped by difficult economic circumstances for which distrust might have a rational basis.info:eu-repo/semantics/publishedVersio