Analysis of the antioxidant activity and caffeine content of Barbula indica (Hook.) Spreng. (Bryophyta; Pottiaceae)

The current research aims to investigate the phytochemical content of Barbula indica different solvents, its antioxidant properties and quantification of the caffeine content in a methanolic extract by high-performance thin-layer chromatography (HPTLC). The total alkaloid content was higher in the methanolic extract, 32.06±0.28 mg/g. The antioxidant properties were evaluated by using DPPH and NOSA; the IC50 values of DPPH and NOSA were 61.09±1.26 µg/mL and 58.04±0.46 µg/mL, respectively. TLC and HPTLC are advanced standardization procedures that provide quantitative and semi-quantitative data about the active compound present in a sample. The development of such a biochemical fingerprint can be used to differentiate the species and adulterants through the analysis of phytochemical content and thus can serve as biochemical markers in pharmacological research and studies related to plant systematics

Resurrection plants: Imperative resources in developing strategies to drought and desiccation pressure

Resurrection plants are the vital assets of nature that have amazing mechanism to restrict the negative impacts of drought or desiccation stress by diminishing cell damage. These surprising plants are in minority on this planet but have the potential to serve as a powerful resource for developing new strategies for major crop plants that are unable to adapt well to the arid climate. In this review, an attempt is made to highlight the potential aspects of these resurrection plants especially the genetic engineering facet which has been done to develop drought tolerance in economically important plants

Responses of Rhizophora mangle L. to effluents from textile Industry in Kano, Nigeria

Polluted water discharge sourced from industrial effluent has emerge a distressing happening owing to its harmful effects on health, lives and safety of organisms. The extent of this unpleasant situation by and large remains unidentified. Thus, in the present study, the toxic effects of effluents from textile are analyzed through Rhizophora mangle L., by leaving it to polluted surface water by effluent from the Challawa stream.  An observation on the effects of textile effluent polluted water was analyzed on the growth, chlorophyll content, heavy metal quantification and membrane integrity in R. mangle was carried out. Seedlings raised from viviparous seeds (propagules) were grown in 50L effluent water from textile industry for 4 weeks.  Growth, physiological, biochemical parameters as well as quantification analysis of heavy metals of the seedlings were analysed immediately after the treatment period. The results proved that R. mangle seedlings were sensitive to metal toxicity. The treatment significantly reduced the growth index and chlorophyll contents evaluated. MDA content, catalase enzyme and heavy metal content (Fe, Ni and Cu) significantly increase when plants were grown in effluent water indicating ROS production. Therefore, this result implies that metals present in the textile effluent induce oxidative stress and membrane damage in R. mangle

Biodegradation of endosulfan by mixed bacteria culture strains of Pseudomonas aeruginosa and Staphylococcus aureus

Endosulfan is a synthetic cyclodiene non-systemic insecticide and acaricide with both contact and stomach activity. Microorganisms play a key role in removal of xenobiotics like endosulfan from the contaminanted sites because of their dynamic, complex, and complicated enzymatic systems which degrade these chemical. In this study, endosulfan was degraded by indigenous bacteria strains of Pseudomonas aeruginosa and Staphylococcus aureus. The biodegradation process was carried out according to the method established by Buff et al., 1992. The results obtained showed that the bacterial strains efficiently degraded endosulfan by consuming more than 90 % of 40 mg/l of the minimal media within 7 days of incubation. Maximum biodegration by these two selected bacterial stains was observed at an initial pH of 8.0 at an incubation temperature of 30 °C. The findings from present study suggest that these bacterial strains could be potentially promising as a low cost effective technology in the biodegradation of endosulfan from the environment.Keywords: Endosulfan, Microoganisms, Biodegradation, Contamination and Soi

Effect of nitrogen application on the phytochemical production in Jatropha curcas L. (Angiosperms: Euphorbiaceae) during drought conditions

Nitrogen is an important nutrient for the successful metabolism of plants, but its occurrence in soil is always very limited. This nutrient has a significant role to preserve plants during various stress conditions by altering the production rate of phytochemicals as defense weapons. Hence, this study was carried out to analyze the effect of nitrogen supply on the phytochemical composition and relative water content in Jatropha curcas L. under a simulated drought condition. The selected seedlings were grown from stem cuttings and categorized into different treated three groups along with the control. After the completion of the experiment, the growth pattern and phytochemical production were investigated. An increased malondialdehyde activity (MDA) was reported with a reduction in relative water content (RWC) of the leaf and in the biomass of seedlings under drought stress. A significant decrease in the levels of alkaloids, phenol, flavonoids and tannins with an increase in saponins and terpenoids was also observed in only simulated drought stressed plants. While a significant increase in the levels of total alkaloid, tannins, flavonoids and phenols was observed in those plants where exogenous nitrogen was supplied before the start of drought periods, unlike in treated and control plants. Therefore, it was revealed that application of Nitrogen enabled the plants to possess protective mechanism through the production of phytochemicals that facilitate the cell membrane to reduce the detrimental effects caused by drought stress

A systematic review of factors influencing Type 2 Diabetes Mellitus management in Nigerian public hospitals

© 2019 Introduction: Type 2 Diabetes Mellitus (T2DM) is often a preventable type of Diabetes Mellitus (DM). However, if developed, can be managed effectively, even at a low-or-no cost. A critical evaluation of the literature on T2DM management in Nigeria reveals sparse evidence-base surrounding external and internal context-specific factors influencing T2DM management in public hospitals across Nigeria. Identification of these factors is crucial to health policy, research, and patient management. This review provides holistic evidence about the influencing factors in public hospitals across Nigeria. Methods: We synthesised quantitative studies on T2DM management, published between 2006 and 2016 in Nigerian public hospitals. Searches of PsycINFO, EMBASE, and Google Scholar databases were undertaken, alongside the African Journals Online (AJOL) and the Cochrane Library resources. The websites of the World Health Organisation African Region (WHO, AFR) and International Diabetes Federation African Region (IDF, AFR) were also searched. The Critical Appraisal Skills Programme (CASP) and Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) checklists were used for quality appraisal and report. Results: This review revealed factors such as non-adherence/non-compliance (20 studies), self-care related (9 studies), psychological-related (6 studies), social-related (6 studies), cost-related (6 studies) and drug-related (3 studies). Impacts of these factors on patient health outcome were elevated glycaemic levels, poor self-management skills, early development of DM complications, and loss of trust in clinical management as well as high mortality rate. Conclusion: The outcome of this review offers practical recommendations for policy review and suggestions for potential change implementation to improve T2DM patient management in the context of clinical practice

Salicylic Acid Enhances Growth, Photosynthetic Performance and Antioxidant Defense Activity Under Salt Stress in Two Mungbean [Vigna radiata (L.) R. Wilczek] Variety

Salt is regarded as a main cause for reduced yield under challenging conditions. Mungbean, a valuable protein crop, is sensitive to salt stress, leading to yield shortage. The growth hormone, salicylic acid (SA), enhances several processes necessary to confer salt tolerance and relieves poor agricultural yield. Seeds of mungbean were initially pretreated with SA (0.5 mM) for 4 h before sowing, while under a cumulative combination of SA + salt regimes: control, SA, 100 mM, SA +100 mM, 200 mM and SA +200 mM. Our study examined photosynthesis parameters such as photosynthetic pigment concentration, chlorophyll a fluorescence, protein, proline, and antioxidant enzymes in plants subjected to single and combined SA + salt stress concentrations. The result showed a greater decline in SPAD and photosynthetic quantum yield under 200 mM NaCl at 43% in Var. 145 than in Var. 155 at 32% compared to 11% in SA +100 mM and 34% in SA + 200 mM treatments in both varieties. Var. 145 was found to be more sensitive to 100 and 200 mM NaCl salt stress. In Var. 155, chlorophyll a and chlorophyll b concentrations were higher under control 52%, SA + 100 mM 49%, and SA +200 mM 42% than in Var. 145 at 51%, 38%, and 31%. Protein and proline revealed a higher content in Var. 155 in contrast to the lower activity in Var. 145. The enhanced performance of the Var. 155 exposed to SA + salt stress was followed by an increase in the activities of peroxidase (POD), CAT while the activity of MDA revealed a significant increase in Var. 145 under 100 mM 43% and 200 mM 48% NaCl treatment compared to Var. 155, which had 38% and 34%. The above results suggest that SA-treated Var. 155 confers tolerance to salt stress and is accompanied with a high osmoprotectant responses as provided by SA in Var. 155 than Var. 145. The potency of SA in providing salt tolerance capacity to plants is a future research interest to maintain sustainable yield in mungbean seedlings

Silicon ameliorates cadmium (Cd) toxicity in pearl millet by inducing antioxidant defense system

Cadmium (Cd) stress is a significant environmental pollutant that can negatively impact crop yield and growth, and is a serious global issue. However, silicon (Si) has been shown to have a potential function in alleviating the effects of several abiotic stress conditions on crops, including Cd stress. This study investigated the effectiveness of applying silicon to soil as a method for reducing cadmium toxicity in pearl millet (IP14599) seedlings. Seeds of IP14599 were treated with Si + Cd element which cumulated to a combination of 9 treatments. Different Cd concentration of (0, 200, and 300 mg/kg-1) was taken and manually mixed into a sieved soil prior to planting and Si (0, 100 and 200 mg/kg-1) was selectively introduced till after attaining 12 days of seedling emergence. The physiochemical parameters of Cd stressed plants investigated includes chlorophyll, gas exchange attributes, proline, relative water contents, malondialdehyde (MDA) content and antioxidant enzymes (superoxide dismutase (SOD),catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD). Our result revealed that the metal (Cd) caused serious oxidative impairment thereby reducing photosynthetic performance, increased activity of MDA and Cd content in the roots and leaves of IP14599.In addition, Si increased the growth pattern and antioxidant defense action thereby mitigating the Cd toxicity. The results revealed that at Si 200, Si significantly increased the chlorophyll, carotenoids and plant height at 122 %, 69 % and 128 % under the Cd 200 and Cd 300 mg/kg-1 treatment, respectively. The single treatment at Si100 and Si 200 decreased ROS by 29 %, and 37 % respectively and MDA decreased by 33 % and 43 % in contrast to Cd 200 and 300 treatments, respectively. However, Si200 showed significant increase in the activities of APX 97 %, SOD by 89 %, CAT 35 % and POD 86 % as compared to single Si, Cd or combine Cd + Si treatment. Also, a gradual decline in Cd level in both the leaf and root was present when exposed to high concentrations of Si at Si200 and 300 mg/kg-1. Our findings revealed that Si might significantly increase the capacity to tolerate Cd stress in crop plants. Therefore, the study revealed that Si has the potential to alleviate Cd-induced toxicity by reducing Cd assimilation and enhancing the growth attributes of IP14599 plants

Risk of COVID-19 after natural infection or vaccinationResearch in context

Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health