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Genomic mutation of the virus may impact the viral adaptation to the local environment, their transmission, disease manifestation, and the effectiveness of existing treatment and vaccination. The objectives of this study were to characterize genomic variations, non-synonymous amino acid substitutions, especially in target proteins, mutation events per samples, mutation rate, and overall scenario of coronaviruses across the country. To investigate the genetic diversity, a total of 184 genomes of virus strains sampled from different divisions of Bangladesh with sampling dates between the 10th of May 2020 and the 27th of June 2020 were analyzed. To date, a total of 634 mutations located along the entire genome resulting in non-synonymous 274 amino acid substitutions in 22 different proteins were detected with nucleotide mutation rate estimated to be 23.715 substitutions per year. The highest non-synonymous amino acid substitutions were observed at 48 different positions of the papain-like protease (nsp3). Although no mutations were found in nsp7, nsp9, nsp10, and nsp11, yet orf1ab accounts for 56% of total mutations. Among the structural proteins, the highest non-synonymous amino acid substitution (at 36 positions) observed in spike proteins, in which 9 unique locations were detected relative to the global strains, including 516E>Q in the boundary of the ACE2 binding region. The most dominated variant G614 (95%) based in spike protein is circulating across the country with co-evolving other variants including L323 (94%) in RNA dependent RNA polymerase (RdRp), K203 (82%) and R204 (82%) in nucleocapsid, and F120 (78%) in NSP2. These variants are mostly seen as linked mutations and are part of a haplotype observed in Europe. Data suggest effective containment of clade G strains (4.8%) with sub-clusters GR 82.4%, and GH clade 6.4%.HighlightsWe have sequenced 137 and analyzed 184 whole-genomes sequences of SARS-CoV-2 strains from different divisions of Bangladesh.A total of 634 mutation sites across the SARS-CoV-2 genome and 274 non-synonymous amino acid substitutions were detected.The mutation rate of SARS-CoV-2 estimated to be 23.715 nucleotide substitutions per year.Nine unique variants were detected based on non-anonymous amino acid substitutions in spike protein relative to the global SARS-CoV-2 strains.

Background: Metabolic syndrome is a risk factor for cardiovascular disease. Objectives: The purpose of the present study was to see the association of metabolic syndrome with essential hypertension. Methodology: This cross sectional study was carried out in the OPD of the Department of Cardiology at Shaheed Suhrawardy Medical college Hospital, Dhaka from January 2008 to December 2010. All the All the Metabolic syndrome was defined as abnormal fasting serum level of glucose (≥ 110 mg/dl or 6.1 mmol/L) with abdominal obesity (waist circumference > 102 cm in men and > 88cm in women), triglycerides (≥ 150mg/dl), High density lipoprotein cholesterol (< 40 mg/dl in men and < 50 mg/dl in women) and hypertension. Results: . A total of 322 patients were enrolled Among hypertensive patients 31.8% had hyperglycemia, 37.9% had high waist circumference, 69.8% had low HDL cholesterol and 54.3% high triglycerides. As per definition of NCEP-ATP-III, metabolic syndrome had been detected in 17% of male, 37% of female and 27% of total population. Conclusion: Metabolic factors are a common association in hypertensive cases. These patients are at increased risk of coronary and cerebro-vascular disease and require more vigorous prevention. Furthermore in all hypertensive patients metabolic screening is recommended. Journal of Science Foundation 2014;12(2): 34-38 DOI: http://dx.doi.org/10.3329/jsf.v12i2.27736

The prevalence of non-communicable diseases (NCD) like diabetes, hypertension, dyslipidemia and atherosclerotic cardiovascular diseases (CVD) are on the increase globally and predominantly in the South East Asian Region (SEAR). The increasing NCD and its complications burdened the health cost of Bangladesh. The available literatures suggest that edible mushrooms are effective in controlling metabolic risks like hyperglycemia and hypercholesterolemia.The study addressed the metabolic effects of edible oyster mushroom (Pleurotus ostreatus) in diabetic individuals and to assess the undesirable effects of mushroom.A total of 5000 newly registered diabetic women were screened for eligible participants (urban housewives, age 30 – 50y, BMI 22 – 27, FBG 8 – 12 mmol/l; free from complications or systemic illnesses and agreed to adhere to the study for 360 days). The investigations included weight and height for BMI, waist- and hip-girth for WHR, BP, FBG, 2ABF, T-chol, TG, HDL, LDL, ALT and Creatinine starting from the day 0 (baseline) and each subsequent follow-up days: 60, 120, 180, 240, 300 and 360 for comparison between placebo and mushroom groups and also within group (baseline vs. follow up days), individually for placebo and mushroom. The daily intake of mushroom was 200g for the mushroom group and an equivalent calorie of vegetables for the placebo group.Overall, 73 diabetic housewives (mushroom / placebo = 43 /30) volunteered. The mean (with SEM) values of BMI, WHR, BP, FBG, 2ABF, T-chol, TG, HDL, LDL, ALT and Creatinine of the placebo group were compared with the mushroom group. Compared with the placebo, the mushroom group showed significant reductions of FBG (p

The study was conducted to select the best promising keratinolytic bacterial strain. A good keratinase positive bacterium isolated from the soil samples of Hazaribagh tannery industrial zone, Dhaka was identified as Arthrobacter genus depending on the conventional techniques and confirmed as Arthrobacter sp. by sequencing 16S rRNA gene. The medium components and culture conditions were optimized to enhance keratinase production through shake flask culture. Keratin and feather powder (10 g/l or 1%) were good substrates for the highest keratinase production along with yeast extract (0.2 g/l or 0.02%) as an organic nitrogen source and potassium nitrate (1 g or 0.1%) as an inorganic nitrogen source. Maximum yield of keratinase was found after 24 h of incubation at 37 °C with an initial pH of 7.0 and inoculums volume 5% under 150 rpm when keratin, yeast extract and potassium nitrate were used as nutrient sources. Keratinase production was more than 5.0-fold increased when all optimized parameters were applied simultaneously. The optimum reaction temperature and pH were determined to be 40 °C and 8.0 respectively for crude keratinase activity. Therefore, Arthrobacter sp. NFH5 might be used for large scale production of keratinase for industrial purposes in less time. Electronic supplementary material The online version of this article (doi:10.1186/s13568-017-0462-6) contains supplementary material, which is available to authorized users.

The present study demonstrates the first direct evidence of the novel role of OsACA6 in providing Cd 2+ stress tolerance in transgenic tobacco by maintaining cellular ion homeostasis and modulating ROS-scavenging pathway. Cadmium, a non-essential toxic heavy metal, interferes with the plant growth and development. It reaches the leaves through xylem and may become part of the food chain, thus causing detrimental effects to human health. Therefore, there is an urgent need to develop strategies for engineering plants for Cd2+ tolerance and less accumulation. The members of P-type ATPases family transport metal ions including Cd2+, and thus play important role an ion homeostasis. The present study elucidates the role of P-type 2B Ca2+ ATPase (OsACA6) in Cd2+ stress tolerance. The transcript levels of OsACA6 were up-regulated upon Cd2+, Zn2+ and Mn2+ exposure. Transgenic tobacco expressing OsACA6 showed tolerance towards Cd2+ stress as demonstrated by several physiological indices including root length, biomass, chlorophyll, malondialdehyde and hydrogen peroxide content. The roots of the transgenic lines accumulated more Cd2+ as compared to shoot. Further, confocal laser scanning microscopy showed that Cd2+ exposure altered Ca2+ uptake in OsACA6 transgenic plants. OsACA6 expression in tobacco also protected the transgenic plants from oxidative stress by enhancing the activity of enzymatic (SOD, CAT, APX, GR) and non-enzymatic (GSH and AsA) antioxidant machinery. Transgenic lines also tolerated Zn2+ and Mn2+ stress; however, tolerance for these ions was not as significant as observed for Cd2+ exposure. Thus, overexpression of OsACA6 confers Cd2+ stress tolerance in transgenic lines by maintaining cellular ion homeostasis and modulating reactive oxygen species (ROS)-scavenging pathway. The results of the present study will help to develop strategies for engineering Cd2+ stress tolerance in economically important crop plants.

Chronic kidney disease (CKD) with diabetes mellitus is one of the most common and major public health problems globally. In Bangladesh, several studies indicate an increasing prevalence of diabetes though very few studies are available on CKD. For CKD, diagnostic method, criteria or cutoffs still remained undecided. This study aimed to determine the prevalence of CKD among the hospitalized patients and to compare the diagnostic approach practiced in the hospital. Methods: All patients admitted to the Department of Nephrology at BIRDEM from May 1 to July 31, 2012 were selected for investigation. An almost equal number of patients were also selected from other units of Medicine. The information included were age, sex, social class, blood pressure, height, weight, blood glucose, creatinine, triglycerides, total cholesterol, high-density lipoproteins and electrolytes. The CKDcreat was diagnosed based on creatinine (>1.2mg/dl) and the CKDgfr based on estimated GFR (1.2 mg/dl) groups. Similar comparisons were also made between CKDgfr and non-CKDgfr (>60 vs. ? 60 ml/min/1.732) groups. Results: A total of 4172 patients got admitted in the study period of 90 days; and 442 patients (m / f = 256 / 186) were investigated. Of the total (n=4172), 241 (5.8%) had CKDcreat and 272 (6.5%) had CKDgfr. Of the investigated 442 patients, 241 (54.5%) had CKDcreat and 272 (61.5%) had CKDgfr. The differences of characteristics between CKDcreat and non-CKDcreat groups were almost similar to the differences between CKDgfr and non-CKDgfr groups. Higher age, higher social class and higher blood pressure showed significant (p1.2 mg/dl and CKDgfr

The p68, a prototypic member of DEAD-box protein family, is involved in pre-mRNA splicing, RNA-induced silencing and transcription regulation. However, the role of plant p68 in stress tolerance and molecular targets responsible for this has not been reported. Here, we report the isolation and characterization of salinity-induced pea p68 (Psp68). The expression of Psp68 was more in aerial parts as compared to the roots in response to the abiotic stress. The transgenic-overexpressing Psp68 showed enhanced tolerance to salinity stress by efficiently attenuating ionic adjustment and scavenging reactive oxygen species (ROS). The enhanced tolerance was further confirmed by observing several physiological indices. Psp68-overexpressing rice accumulated higher K+ and Ca2+ and lower Na+ level as compared to the wild-type (WT) plants. Furthermore, Psp68 interacts with pea argonaute (AGO1), a catalytic component of the RNA-induced silencing complex (RISC) responsible for the gene silencing. The microarray analysis showed that Psp68 regulates many transcripts involved in the abiotic and oxidative stress responses as well as gene-silencing mechanisms in rice. Thus, the Psp68 functions as a molecular switch in different signaling pathways leading to stress tolerance. Overall, Psp68 may serve as a useful biotechnological tool for the improvement of stress tolerance crops.

Calcium (Ca²⁺) regulates several signalling pathways involved in growth, development and stress tolerance. Cellular Ca²⁺ homeostasis is achieved by the combined action of channels, pumps and antiporters, but direct evidence for a role of Ca²⁺ATPase pumps in stress tolerance is lacking. Here we report the characterization of a Ca²⁺ ATPase gene (OsACA6) from Oryza sativa, and elucidate its functions in stress tolerance. OsACA6 transcript levels are enhanced in response to salt, drought, abscisic acid and heat. In vivo localization identified plasma membranes as an integration site for the OsACA6-GFP fusion protein. Using transgenic tobacco lines, we demonstrate that over-expression of OsACA6 is triggered during salinity and drought stresses. The enhanced tolerance to these stresses was confirmed by changes in several physiological indices, including water loss rate, photosynthetic efficiency, cell membrane stability, germination, survival rate, malondialdehyde content, electrolyte leakage and increased proline accumulation. Furthermore, over-expressing lines also showed higher leaf chlorophyll and reduced accumulation of H₂O₂ and Na⁺ ions compared to the wild-type. Reduced accumulation of reactive oxygen species (ROS) was observed in transgenic lines. The increased proline accumulation and ROS scavenging enzyme activities in transgenic plants over-expressing OsACA6 efficiently modulate the ROS machinery and proline biosynthesis through an integrative mechanism. Transcriptional profiling of these plants revealed altered expression of genes encoding many transcription factors, stress- and disease-related proteins, as well as signalling components. These results suggest that Ca²⁺ ATPases have diverse roles as regulators of many stress signalling pathways, leading to plant growth, development and stress tolerance.

Food security is in danger under the continuous growing threat of various stresses including climate change and global warming, which ultimately leads to a reduction in crop yields. Calcium plays a very important role in many signal transduction pathways including stress signalling. Different extracellular stimuli trigger increases in cytosolic calcium, which is detrimental to plants. To cope with such stresses, plants need to develop efficient efflux mechanisms to maintain ionic homeostasis. The Ca(2+)-ATPases are members of the P-type ATPase superfamily, which perform many fundamental processes in organisms by actively transporting ions across cellular membranes. In recent years, many studies have revealed that, as well as efflux mechanisms, Ca(2+)-ATPases also play critical roles in sensing calcium fluctuations and relaying downstream signals by activating definitive targets, thus modulating corresponding metabolic pathways. As calcium-activated calmodulin (CaM) is reported to play vital roles in stress tolerance, the presence of a unique CaM-binding site in type IIB Ca(2+)-ATPases indicates their potential role in biotic as well as abiotic stress tolerance. The key roles of Ca(2+)-ATPases in transport systems and stress signalling in cellular homeostasis are addressed in this review. A complete understanding of plant defence mechanisms under stress will allow bioengineering of improved crop plants, which will be crucial for food security currently observed worldwide in the context of global climate changes. Overall, this article covers classification, evolution, structural aspects of Ca(2+)-ATPases, and their emerging roles in plant stress signalling.

Embracing micro-propagation method for large scale production of plantlets and also for protection of appropriate germplasm is a prerequisite that needs to be undertaken in order to develop a rapid in vitro regeneration protocol for Ocimum sanctum L. Shoot tips as well as nodal segments were subjected to numerous shoots inducement. Explants were cultured on Murashige and Skoog Basal Medium (MS) supplemented for different plants’ development controllers. HgCl 2 was utilized as a surface disinfecting agent. Nowadays, many researchers do not use HgCl 2 , so 1% sodium hypochlorite can be used. Cleaned explants were chiseled to 3-4cm length at right edges. The explants were inoculated vertically on the culture medium. The cultures were incubated at 25±2°C under cool fluorescent light. The photoperiod was set at 16 h light and 8 h darkness by automated timer. Data on shoot induction and expansion and root induction were recorded following three weeks of inoculation and utilized for figuring. Built up plantlets were transplanted in earthen pots under circumstances and outliving degree was recited. The practically viable surface sanitization medication for explants of O. sanctum was discovered at 0.1% HgCl 2 for 7 min. 1% sodium hypochlorite also showed same result. Maximum number of shoots per culture was recorded in MS medium containing 2.0 mg/l BAP in a mixture of 0.5 mg/l NAA. Regenerated shoots of O. sanctum were rooted most effectively in full MS medium supplemented with 1.0 mg/l NAA. It was observed that nodal segments are more responsive to micropropagation than shoot tips. This protocol is used to explore the opportunities of utilizing O. sanctum L., as important medicinal plant of Bangladesh, in modern medical health care system by rapid clonal propagation, and germplasm conservation. The developed plants were acclimatized in pot successfully and also maintained in normal environment. Keywords: Ocimum sanctum , micro-propagation, explants, nodal segments, medicinal plant, regeneration

Cadmium (Cd) stress significantly decreased membrane integrity and impaired the ascorbate (ASC)-glutathione (GSH) cycle in tobacco Bright Yellow-2 cells. Exogenous application of proline and glycinebetaine (betaine) significantly restored the membrane integrity and increased the activities of ASC-GSH cycle enzymes under Cd stress without maintenance of the rich ASC or GSH pools. Moreover, proline offered more efficient protection against Cd stress than betaine.

BackgroundThe DEAD-box helicases are required mostly in all aspects of RNA and DNA metabolism and they play a significant role in various abiotic stresses, including salinity. The p68 is an important member of the DEAD-box proteins family and, in animal system, it is involved in RNA metabolism including pre-RNA processing and splicing. In plant system, it has not been well characterized. Here we report the cloning and characterization of p68 from pea (Pisum sativum) and its novel function in salinity stress tolerance in plant.ResultsThe pea p68 protein self-interacts and is localized in the cytosol as well as the surrounding of cell nucleus. The transcript of pea p68 is upregulated in response to high salinity stress in pea. Overexpression of p68 driven by constitutive cauliflower mosaic virus-35S promoter in tobacco transgenic plants confers enhanced tolerances to salinity stress by improving the growth, photosynthesis and antioxidant machinery. Under stress treatment, pea p68 overexpressing tobacco accumulated higher K+ and lower Na+ level than the wild-type plants. Reactive oxygen species (ROS) accumulation was remarkably regulated by the overexpression of pea p68 under salinity stress conditions, as shown from TBARS content, electrolyte leakage, hydrogen peroxide accumulation and 8-OHdG content and antioxidant enzyme activities.ConclusionsTo the best of our knowledge this is the first direct report, which provides the novel function of pea p68 helicase in salinity stress tolerance. The results suggest that p68 can also be exploited for engineering abiotic stress tolerance in crop plants of economic importance.

Background Plasma membrane Ca2+ATPase is a transport protein in the plasma membrane of cells and helps in removal of calcium (Ca2+) from the cell, hence regulating Ca2+ level within cells. Though plant Ca2+ATPases have been shown to be involved in plant stress responses but their promoter regions have not been well studied. Results The 1478 bp promoter sequence of rice plasma membrane Ca2+ATPase contains cis-acting elements responsive to stresses and plant hormones. To identify the functional region, serial deletions of the promoter were fused with the GUS sequence and four constructs were obtained. These were differentially activated under NaCl, PEG cold, methyl viologen, abscisic acid and methyl jasmonate treatments. We demonstrated that the rice plasma membrane Ca2+ATPase promoter is responsible for vascular-specific and multiple stress-inducible gene expression. Only full-length promoter showed specific GUS expression under stress conditions in floral parts. High GUS activity was observed in roots with all the promoter constructs. The −1478 to −886 bp flanking region responded well upon treatment with salt and drought. Only the full-length promoter presented cold-induced GUS expression in leaves, while in shoots slight expression was observed for −1210 and −886 bp flanking region. The −1210 bp deletion significantly responded to exogenous methyl viologen and abscisic acid induction. The −1210 and −886 bp flanking region resulted in increased GUS activity in leaves under methyl jasmonate treatments, whereas in shoots the −886 bp and −519 bp deletion gave higher expression. Salicylic acid failed to induce GUS activities in leaves for all the constructs. Conclusions The rice plasma membrane Ca2+ATPase promoter is a reproductive organ-specific as well as vascular-specific. This promoter contains drought, salt, cold, methyl viologen, abscisic acid and methyl jasmonate related cis-elements, which regulated gene expression. Overall, the tissue-specificity and inducible nature of this promoter could grant wide applicability in plant biotechnology.

Methylglyoxal (MG) is one of the aldehydes accumulated in plants under environmental stress. Cytosolic ascorbate peroxidase (cAPX) plays a key role in the protection of cells from oxidative damage by scavenging reactive oxygen species in higher plants. A cDNA encoding cAPX, named NtcAPX, was isolated from Nicotiana tabacum. We characterized recombinant NtcAPX (rNtcAPX) as a fusion protein with glutathione S-transferase to investigate the effects of MG on APX. NtcAPX consists of 250 amino acids and has a deduced molecular mass of 27.5 kDa. The rNtcAPX showed a higher APX activity. MG treatments resulted in a reduction of APX activity and modifications of amino groups in rNtcAPX with increasing Km for ascorbate. On the contrary, neither NaCl nor cadmium reduced the activity of APX. The present study suggests that inhibition of APX is in part due to the modification of amino acids by MG. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:315–321, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21423

Methylglyoxal (MG) is one of the aldehydes that accumulate in plants under environmental stress. Glutathione S-transferases (GSTs) play important roles, including detoxification, in the stress tolerance systems of plants. To determine the effects of MG, we characterized recombinant GST. MG decreased GST activity and thiol contents with increasing K(m). GST can serve as a target of MG modification, which is suppressed by application of reduced glutathione.

Environmental stress, including heavy metal stress, can cause oxidative damage to plants. Up-regulation of the antioxidant defense system induced by proline and glycinebetaine (betaine) alleviates the damaging effects of oxidative stress in plants. Here, we investigated the protective effects of exogenously applied proline and betaine on growth, accumulation of proline and betaine, lipid peroxidation and activity of antioxidant enzymes in cultured tobacco Bright Yellow-2 (BY-2) cells exposed to cadmium (Cd) stress. Cadmium stress (at 100 microM Cd) caused a significant inhibition of the growth of BY-2 cells, and both proline and betaine significantly mitigated this inhibition. In addition, the mitigating effect of proline was more pronounced than that of betaine. Cadmium stress leads to an accumulation of Cd and endogenous proline in cultured cells, increased lipid peroxidation and peroxidase (POX) activity, and decreased activity of superoxide dismutase (SOD) and catalase (CAT). Exogenous application of proline resulted in a decrease in lipid peroxidation and an increase in SOD and CAT activities without reducing Cd contents under Cd stress, while application of betaine resulted in a decrease in lipid peroxidation and an increase in CAT activity with reducing Cd accumulation. Furthermore, exogenous proline and betaine intensified the accumulation of proline and betaine in Cd-stressed BY-2 cells, respectively. The present study suggests that proline and betaine confer tolerance to Cd stress in tobacco BY-2 cells by different mechanisms.

Summary Salt stress causes oxidative damage and cell death in plants. Plants accumulate proline and glycinebetaine (betaine) to mitigate detrimental effects of salt stress. The aim of this study was to investigate the protective effects of proline and betaine on cell death in NaCl-unadapted tobacco (Nicotiana tabacum) Bright Yellow-2 suspension-cultured cells subjected to salt stress. Salt stress increased reactive oxygen species (ROS) accumulation, lipid peroxidation, nuclear deformation and degradation, chromatin condensation, apoptosis-like cell death and ATP contents. Neither proline nor betaine affected apoptosis-like cell death and G1 phase population, and increased ATP contents in the 200 mM NaCl-stressed cells. However, both of them effectively decreased ROS accumulation and lipid peroxidation, and suppressed nuclear deformation and chromatin condensation induced by severe salt stress. Evans Blue staining experiment showed that both proline and betaine significantly suppressed increment of membrane permeability induced by 200 mM NaCl. Furthermore, among the ROS scavenging antioxidant defense genes studied here, mRNA levels of salicylic acid-binding (SAbind) catalase (CAT) and lignin-forming peroxidase (POX) were found to be increased by proline and betaine under salt stress. It is concluded that both proline and betaine provide a protection against NaCl-induced cell death via decreasing level of ROS accumulation and lipid peroxidation as well as improvement of membrane integrity.

Salt stress impairs reactive oxygen species (ROS) and methylglyoxal (MG) detoxification systems, and causes oxidative damage to plants. Up-regulation of the antioxidant and glyoxalase systems provides protection against NaCl-induced oxidative damage in plants. Thiol-disulfide contents, glutathione content and its associated enzyme activities involved in the antioxidant defense and glyoxalase systems, and protein carbonylation in tobacco Bright Yellow-2 cells grown in suspension culture were investigated to assess the protection offered by proline and glycinebetaine against salt stress. Salt stress increased protein carbonylation, contents of thiol, disulfide, reduced (GSH) and oxidized (GSSG) forms of glutathione, and the activity of glutathione-S-transferase and glyoxalase II enzymes, but decreased redox state of both thiol-disulfide and glutathione, and the activity of glutathione peroxidase and glyoxalase I enzymes involved in the ROS and MG detoxification systems. Exogenous application of proline or glycinebetaine resulted in a reduction of protein carbonylation, and in an increase in glutathione redox state and activity of glutathione peroxidase, glutathione-S-transferase and glyoxalase I under salt stress. Neither proline nor glycinebetaine, however, had any direct protective effect on NaCl-induced GSH-associated enzyme activities. The present study, therefore, suggests that both proline and glycinebetaine provide a protective action against NaCl-induced oxidative damage by reducing protein carbonylation, and enhancing antioxidant defense and MG detoxification systems.

Up-regulation of the antioxidant system provides protection against NaCl-induced oxidative damage in plants. Antioxidants and activity of enzymes involved in the ascorbate-glutathione (ASC-GSH) cycle in tobacco Bright Yellow-2 (BY-2) were investigated to assess the antioxidant protection offered by exogenous proline and glycinebetaine (betaine from now on) against salt stress using cells grown in suspension culture. Reduced ascorbate (ASC) was detected in BY-2 cells but dehydroascorbate (DHA) was not. Large quantities of a reduced form of glutathione (GSH) and smaller quantities of an oxidized form of glutathione (GSSG) were detected in BY-2 cells. Salt stress significantly reduced the contents of ASC and GSH as well as activities of ASC-GSH cycle enzymes such as ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR). Exogenous proline or betaine increased the activities of all enzymes except MDHAR involved in NaCl-induced ASC-GSH cycle. Levels of ASC and GSH in BY-2 cells under salt stress were lower in the presence of proline or betaine than in the absence of proline or betaine whereas there was no difference in redox status. Proline proved more effective than betaine in maintaining the activity of enzymes involved in NaCl-induced ASC-GSH cycle. Neither proline nor betaine had any direct protective effect on NaCl-induced enzyme activity involved in the antioxidant system; however, both improved salt tolerance by increasing enzyme activity. The present study, together with our earlier findings [Hoque MA, Okuma E, Banu MNA, Nakamura Y, Shimoishi Y, Murata Y. Exogenous proline mitigates the detrimental effects of salt stress more than exogenous betaine by increasing antioxidant enzyme activities. J Plant Physiol 2006;164:553-61.], suggests that proline offered greater protection against salt stress than betaine did because proline was more effective in increasing the activity of enzymes involved in the antioxidant system.

Proline and betaine accumulate in plant cells under environmental stresses including salt stress. Here, we investigated effects of proline and betaine on the growth and activities of antioxidant enzymes in tobacco Bright Yellow-2 (BY-2) culture cells in suspension under salt stress. Both proline and betaine mitigated the inhibition of growth of BY-2 cells under salt stress and the mitigating effect of proline was more than that of betaine. Salt stress significantly decreased the activities of superoxide dismutase (SOD), catalase and peroxidase in BY-2 cells. Exogenous application of proline or betaine alleviated the reduction in catalase and peroxidase activities but not SOD activity under salt stress. In addition, proline was found to be effective in alleviating the inhibition of salt stress-induced catalase and peroxidase activities in BY-2 cells. Neither proline nor betaine directly scavenged superoxide (O(2)(-)) or hydrogen peroxide (H(2)O(2)). It is concluded that exogenous proline mitigates the detrimental effects of salt stress more than exogenous betaine because of its superior ability to increase the activities of antioxidant enzymes.

Coronary heart disease (CHD) is a major global health problem with the majority of burden observed increasingly in the developing countries. There has been no estimate of CHD in Bangladesh. This study addresses the prevalence of CHD in a Bangladeshi rural population which also aimed to determine the risk factors related to CHD. Ten villages of Nandail sub-district under Mymensingh were selected purposively. All subjects of age ≥20y were considered eligible and were interviewed about family income, family history of T2DM, CHD and HTN. The investigations included height, weight, waist-girth, hip-girth, systolic and diastolic blood pressure (SBP & DBP), fasting blood glucose (FBG), triglycerides (TG), cholesterol (Chol) and high density lipoprotein (HDL). Hemoglobin A1c (HbA1c) and albumin-creatinine ratio (ACR) were also estimated. Finally, electrocardiography (ECG) was undertaken in all participants who had family history of diabetes or hypertension or CHD. Diagnosis of CHD was based on history of angina or changes in ECG or diagnosed by a cardiologist. A total of 6235 subjects were enlisted as eligible (age ≥20y) participants. Of them, 4141 (m / f: 1749 / 2392) subjects volunteered for the study. The age-adjusted (20-69y) prevalence of CHD was 1.85 with 95% CI, 1.42 - 2.28. There was no significant difference between men and women. The mean (SD) values of age (p