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Wedelia chinensis is a folk medicine used in many Asian countries to treat various ailments. Earlier investigations reported that the petroleum ether extract of the plant has potential biological activity, but the compounds responsible for activity are not yet completely known. Therefore, the current work was designed to isolate and characterize the compounds from the petroleum ether extract and to study their bioactivities. Four compounds including two diterepenes (-) kaur-16α-hydroxy-19-oic acid (1) and (-) kaur-16-en-19-oic acid (2), and two steroids ß-sitosterol (3), and cholesta-5,23-dien-3-ol (4) were isolated and characterized. Among the compounds, the diterpenes were found to have more biological activities than the steroidal compounds. Compound 1 showed the highest cytotoxicity with LC50 of 12.42 ± 0.87 µg/mL. Likewise, it possesses good antioxidant activity in terms of reducing power. On the contrary, compound 2 exerted the highest antiacetylcholinesterase and antibutyrylcholinesterase activity. Both the diterpenes showed almost similar antibacterial and antifungal activity. The identification of diterpenoid and steroid compounds with multifunctional activities suggests that W. chinensis may serve as an important source of bioactive compounds which should be further investigated in animal model for therapeutic potential in the treatment of different chronic diseases.
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Diterpenos , Wedelia , Animais , Inibidores da Colinesterase/farmacologia , Antioxidantes/farmacologia , Antibacterianos , Extratos Vegetais/farmacologiaRESUMO
Surface mining is a critical anthropogenic activity that significantly alters the ecosystem, while the use of appropriate revegetation techniques can be considered an important and feasible strategy in the way to improve the ecosystem services of degraded land. In the present study, we carried out a pot experiment to investigate the effects of three different variables on morpho-physiological and biochemical parameters of Onobrychis viciifolia to assess the capability of this species to be used for restoration purposes. Specifically, the variables studied were: (a) water (W) regime, working at five values as regards field capacity (FC) (i.e., 80% FC = highest, 72% FC = high, 60% FC = moderate, 48% FC = low, and 40% FC = very-low dose); and (b) rates of cattle manure compost (CMC) and wood biochar (BC) (weight/weight ratio), working at five rates (i.e., 4.0% = highest, 3.2% = high, 2.0% = moderate, 0.8% = low, and 0% = either no-CMC or no-BC dose). In addition, soil physical-chemical properties and enzyme activities were also investigated at the end of the experimental period. It was found that morphological growth attributes such as plant height, maximum root length, and dry biomass significantly increased with W, CMC and BC applications. Compared to control, moderate-to-high W, CMC and BC doses (W80CMC2BC2) increased net photosynthesis rate (by 42%), stomatal conductance (by 50%), transpiration rate (by 29%), water use efficiency (by 10%), chlorophyll contents (by 73%), carotenoid content (by 81%), leaf relative water content (by 33%) and leaf membrane stability index (by 30%). Under low-W content, the application of CMC and BC enhanced osmotic adjustments by increasing the content of soluble sugar and the activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, decreasing the oxidative stress, as verified by low levels of hydrogen peroxide, superoxide anion, malondialdehyde and proline contents in leaf tissues. Moreover, application of W, CMC and BC significantly improved soil water holding capacity, available nitrogen, phosphorus and potassium, urease and catalase activities, which facilitate plant growth. These results would aid in designing an appropriate strategy for achieving a successful revegetation of O. viciifolia, providing optimum doses of W (64% field capacity), CMC (2.4%) and BC (1.7%), with the final aim of reaching ecological restoration in arid degraded lands.
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Compostagem , Esterco , Animais , Bovinos , Carvão Vegetal , Carvão Mineral , Desidratação , Suplementos Nutricionais , Ecossistema , Solo/químicaRESUMO
Methane (CH4) is one of the dominant greenhouse gases (GHG) that is largely emitted from rice fields and thus, significantly contributes to global warming. Significant efforts have been made to find out suitable strategies to mitigate CH4 emission from rice culture. However, the effectiveness of these management practices is often diverse with negative, no, or positive impacts making it difficult to adopt under a particular condition. The diversity of rice cultivation in terms of agro-climatic conditions and cultivation practices makes it difficult for providing specific recommendations. Here, we collected data from a total of 198 studies reporting 1052 observations. The management practices are categorized into five different management practices i.e., water, organic and inorganic fertilizer management, crop establishment method, and agronomic practices while major categories were subdivided into different classes. To test statistically significant differences in the effectiveness between major management practices, an analysis of variance (ANOVA) was applied. The Gaussian and bootstrapping model were applied to find out the best estimate of the effectiveness of each practice. In addition, mechanisms controlling the CH4 emission reductions were synthesized. Next, the adoption potentials of these practices were assessed based on the existing rice cultivation systems in Bangladesh. Our results showed that water and organic matter management were the most effective methods irrespective of the growing conditions. When these technologies are customized to Bangladesh, water management and crop establishment methods seem most feasible. Among the rice-growing seasons in Bangladesh, there is a larger scope to adopt these management practices in the Boro season (December to May), while these scopes are minimal in the other two seasons due to their rain-fed nature of cultivation. Altogether, our study provides fundamental insights on CH4 reductions strategies from rice fields in Bangladesh.
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Metano , Oryza , Agricultura/métodos , Bangladesh , Metano/análise , Óxido Nitroso/análise , Estações do Ano , SoloRESUMO
Coconut (Cocos nucifera L.) is one of the most important fruit trees in Bangladesh. This tree is susceptible to various pathogens. Among them, a fungus was consistently isolated from gray leaf spot symptom in coconut. This study aimed to isolate, characterize, and find the management strategies of the causal fungus of gray leaf spot disease in coconut. Both morphological and molecular characters identified the pathogen as Pestalotiopsis sp. for the first time in Bangladesh. Artificial inoculation of this fungus showed symptoms similar to those previously observed in the field. Cross-inoculation test suggests that Pestalotiopsis sp. has a wide host range. The infection process of Pestalotiopsis sp. started at 2 h after inoculation (hai) with the formation of germ tube followed by the formation of infection hyphae, which penetrated directly into the host at 6 hai. Gray leaf spot symptom was developed at 120 hai. Numerous conidia developed from the acervuli at 168 hai. These conidia acted as the source of inocula for secondary infection. The optimum temperature for the growth of Pestalotiopsis sp. was 25°C, however, the growth of Pestalotiopsis sp. ceased at 15°C and 35°C. This pathogen was completely inhibited by Autostin 50 WDG (carbendazim) at 100 ppm. Trichoderma viride (Pb-7) was found as the potential biocontrol agent against Pestalotiopsis sp. These findings could contribute to describing the disease cycle and epidemiology of Pestalotiopsis sp. that would ultimately require to undertake effective control measures against this pathogen.
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Cocos , Pestalotiopsis , Bangladesh , Frutas , Doenças das PlantasRESUMO
Electrospinning of a heterogeneous solution is difficult to continue because the required process parameters are different for multiple phases. In this study, nanofibrous mats were successfully prepared from a heterogeneous blend of solid cellulose nanocrystals (CNC) and hydroxyapatite nanoparticles (HAp) in a solution mixture of chitosan and gelatin using an electrospinning technique. HAp and CNC were used as filler materials in the nanofibrous mats. Gelatin and chitosan polymer chains in the mats were crosslinked using glutaraldehyde. The fiber diameter was noticed to decrease from around 86 to 43 nm with the increase of electrical conductivity of the spinning solution from 890 to 1166 µS cm-1 and after crosslinking a significant variation in fibers' diameter was noticed. The elemental analysis data showed that around 85% of the HAp used in the spinning solution was passed through the nozzle and the rest of the portion remained settled in the spinning syringe. In the XRD study, the crystallinity of chitosan, HAp and CNC was not observed in the non-crosslinked and crosslinked mats. The TGA analysis showed that the crosslinked mat has no weight retention at 500 °C which is due to its complete amorphous nature. The mats showed single-phase transition temperatures in DSC analysis which proves that no segregation of materials was present in the electrospun fibers. FTIR analysis of the mats showed a new peak at 1205 cm-1 which suggests the Michael addition type reactions to be happened between chitosan and gelatin. Cytotoxicity analysis of the mats on the vero-cell line showed around 95% of cell viability. The prepared mats were applied as wound dressings on a mice model experiment and 50% faster healing of wounds on the mice was noticed for the non-crosslinked mats than the control one.
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The infant non-secretor histoblood group antigen phenotype is associated with reduced risk of symptomatic rotavirus diarrhea, one of the leading global causes of severe pediatric diarrheal disease and mortality. However, little is known regarding the role of secretor status in asymptomatic rotavirus infections. Therefore, we performed a nested case-control study within a birth cohort study previously conducted in Dhaka, Bangladesh, to determine the association between infant secretor phenotype and the odds of asymptomatic rotavirus infection, in addition to the risk of rotavirus diarrhea, in unvaccinated infants. In the parent cohort, infants were enrolled in the first week of life and followed through the first two years of life with multiple clinic visits and active surveillance for diarrheal illness. Secretor phenotyping was performed on saliva. Eleven surveillance stools collected over the first year of life were tested for rotavirus by real-time RT-PCR, followed by conventional PCR and amplicon sequencing to identify the infecting P-type of positive specimens. Similar to findings for symptomatic diarrhea, infant non-secretors experienced significantly fewer primary episodes of asymptomatic rotavirus infection through the first year of life in a likely rotavirus P-genotype-dependent manner. These data suggest that non-secretors experienced reduced risk from rotavirus due to decreased susceptibility to infection rather than reduced infection severity.
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Background: Monkeypox has emerged as a noteworthy worldwide issue due to its daily escalating case count. This illness presents diverse symptoms, including skin manifestations, which have the potential to spread through contact. The transmission of this infectious agent is intricate and readily transfers between individuals.Methods: The hypothetical protein MPXV-SI-2022V502225_00135 strain of monkeypox underwent structural and functional analysis using NCBI-CD Search, Pfam, and InterProScan. Quality assessment utilized PROCHECK, QMEAN, Verify3D, and ERRAT, followed by protein-ligand docking, visualization, and a 100-nanosecond simulation on Schrodinger Maestro.Results: Different physicochemical properties were estimated, indicating a stable molecular weight (49147.14) and theoretical pI (5.62) with functional annotation tools predicting the target protein to contain the domain of Chordopox_A20R domain. In secondary structure analysis, the helix coil was found to be predominant. The three-dimensional (3D) structure of the protein was obtained using a template protein (PDB ID: 6zyc.1), which became more stable after YASARA energy minimization and was validated by quality assessment tools like PROCHECK, QMEAN, Verify3D, and ERRAT. Protein-ligand docking was conducted using PyRx 9.0 software to examine the binding and interactions between a ligand and a hypothetical protein, focusing on various amino acids. The model structure, active site, and binding site were visualized using the CASTp server, FTsite, and PyMOL. A 100 nanosecond simulation was performed with ligand CID_16124688 to evaluate the efficiency of this protein.Conclusion: The analysis revealed significant binding interactions and enhanced stability, aiding in drug or vaccine design for effective antiviral treatment and patient management.
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Simulação de Acoplamento Molecular , Monkeypox virus , Proteínas Virais , Proteínas Virais/química , Proteínas Virais/metabolismo , Monkeypox virus/química , Simulação por Computador , Humanos , Ligantes , Ligação Proteica , Domínios Proteicos , Simulação de Dinâmica Molecular , Conformação Proteica , Modelos Moleculares , Relação Estrutura-Atividade , Sítios de LigaçãoRESUMO
Breast milk secretor status is associated with antibody seroconversion to oral rotavirus vaccination. Here, we were unable to detect a similar impact on risk of infant rotavirus diarrhea or vaccine efficacy through 2 years of life, underscoring limitations of immunogenicity assessment alone in evaluation of oral rotavirus vaccine response.
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The sodium influx into the cytosol of mesophyll protoplasts from Arabidopsis thaliana cv. Columbia, wild type, was compared with the influx into sos1-1 and nhx1 genotypes, which lack the Na+/H+ antiporter in the plasma membrane and tonoplast, respectively. Changes in cytosolic sodium and calcium concentrations upon a 100 mM NaCl addition were detected by use of epifluorescence microscopy and the sodium-specific fluorescent dye SBFI, AM, and calcium sensitive Fura 2, AM, respectively. There was a smaller and mainly transient influx of Na+ in the cytosol of the wild type compared with the sos1-1 and nhx1 genotypes, in which the influx lasted for a longer time. Sodium chloride addition to the protoplasts' medium induced a significant increase in cytosolic calcium concentration in the wild type at 1.0 mM external calcium, and to a lesser extent in nhx1, however, it was negligible in the sos1-1 genotype. LiCl inhibited the cytosolic calcium elevation in the wild type. The results suggest that the salt-induced calcium elevation in the cytosol of mesophyll cells depends on an influx from both internal and external stores and occurs in the presence of an intact Na+/H+ antiporter at the plasma membrane. The Arabidopsis SOS1 more effectively regulates sodium homeostasis than NHX1.
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Litorilituus sediminis is a Gram-negative, aerobic, novel bacterium under the family of Colwelliaceae, has a stunning hypothetical protein containing domain called von Hippel-Lindau that has significant tumor suppressor activity. Therefore, this study was designed to elucidate the structure and function of the biologically important hypothetical protein EMK97_00595 (QBG34344.1) using several bioinformatics tools. The functional annotation exposed that the hypothetical protein is an extracellular secretory soluble signal peptide and contains the von Hippel-Lindau (VHL; VHL beta) domain that has a significant role in tumor suppression. This domain is conserved throughout evolution, as its homologs are available in various types of the organism like mammals, insects, and nematode. The gene product of VHL has a critical regulatory activity in the ubiquitous oxygen-sensing pathway. This domain has a significant role in inhibiting cell proliferation, angiogenesis progression, kidney cancer, breast cancer, and colon cancer. At last, the current study depicts that the annotated hypothetical protein is linked with tumor suppressor activity which might be of great interest to future research in the higher organism.
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Alzheimer's disease (AD) is a progressive neurological disorder characterized by loss of memory and cognition. Stephania japonica is being used as traditional medicine in the treatment of different neurological problems. In this study, we evaluated the anticholinesterase and antioxidant activities of the crude methanol extract of S. japonica and its fractions in vitro and the neuroprotective effect of the most active fraction in the scopolamine-induced mouse model of memory impairment. Among the crude extract and its fractions, chloroform fraction exerted strong inhibition of acetylcholinesterase and butyrylcholinesterase enzymes with IC50 values of 40.06 and 18.78 µg/mL, respectively. Similarly, the chloroform fraction exhibited potent antioxidant activity and effectively inhibited the peroxidation of brain lipid in vitro. The phytochemical profile revealed the high content of polyphenolics and alkaloids in the chloroform fraction. Pearson's correlation studies showed a significant association of anticholinesterase and antioxidant activity with alkaloid and phenolic contents. Kinetic analysis showed that the chloroform fraction exhibited a noncompetitive type of inhibition. In experimental mice, the chloroform fraction restored the impaired learning and memory induced by scopolamine as evidenced by a significant decrease in latency time and increase of quadrant time in probe trial in Morris water maze task. The chloroform fraction also significantly reduced the activity of acetylcholinesterase and oxidative stress in mice. Our results suggest that the chloroform fraction of S. japonica may represent a potential candidate for the prevention and treatment of AD.
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Colorectal cancer (CRC) is the second most deadly cancer worldwide. CRC management is challenging due to late detection, high recurrence rate, and multi-drug resistance. Herbs and spices used in cooking, practised for generations, have been shown to contain CRC protective effect or even be useful as an anti-CRC adjuvant therapy when used in high doses. Herbs and spices contain many bioactive compounds and possess many beneficial health effects. The chemopreventive properties of these herbs and spices are mainly mediated by the BCL-2, K-ras, and MMP pathways, caspase activation, the extrinsic apoptotic pathway, and the regulation of ER-stress-induced apoptosis. As a safer natural alternative, these herbs and spices could be good candidates for chemopreventive or chemotherapeutic agents for CRC management because of their antiproliferative action on colorectal carcinoma cells and inhibitory activity on angiogenesis. Therefore, in this narrative review, six different spices and herbs: ginger (Zingiber officinale Roscoe), turmeric (Curcuma longa L.), garlic (Allium sativum L.), fenugreek (Trigonella foenum-graecum L.), sesame (Sesamum indicum L.), and flaxseed (Linum usitatissimum L.) used in daily cuisine were selected for this study and analyzed for their chemoprotective or chemotherapeutic roles in CRC management with underlying molecular mechanisms of actions. Initially, this study comprehensively discussed the molecular basis of CRC development, followed by culinary and traditional uses, current scientific research, and publications of selected herbs and spices on cancers. Lead compounds have been discussed comprehensively for each herb and spice, including anti-CRC phytoconstituents, antioxidant activities, anti-inflammatory properties, and finally, anti-CRC effects with treatment mechanisms. Future possible works have been suggested where applicable.
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Over the years, leaked fluids from aircraft have caused severe deterioration of airfield pavement. The combined effect of hot exhaust from the auxiliary power unit of military aircraft and spilt aviation oils have caused rapid pavement spalling. If the disintegrated concreted pieces caused by spalling are sucked into the jet engine, they may cause catastrophic damage to the aircraft engine or physical injury to maintenance crews. This study investigates the effectiveness of incorporating hybrid fibres into ordinary concrete to improve the residual mechanical and thermal properties to prevent spalling damage of pavement. Three fibre-reinforced concrete samples were made with micro steel fibre and polyvinyl alcohol fibre with a fibre content of zero, 0.3%, 0.5% and 0.7% by volume fraction. These samples were exposed to recurring high temperatures and aviation oils. Tests were conducted to measure the effects of repeated exposure on the concrete's mechanical, thermal and chemical characteristics. The results showed that polyvinyl alcohol fibre-, steel fibre- and hybrid fibre-reinforced concrete suffered a 52%, 40% and 26.23% of loss of initial the compressive strength after 60 cycles of exposure to the conditions. Moreover, due to the hybridisation of concrete, flexural strength and thermal conductivity was increased by 47% and 22%. Thus, hybrid fibre-reinforced concrete performed better in retaining higher residual properties and exhibited no spalling of concrete.
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Team formation (TF) in social networks exploits graphs (i.e., vertices = experts and edges = skills) to represent a possible collaboration between the experts. These networks lead us towards building cost-effective research teams irrespective of the geolocation of the experts and the size of the dataset. Previously, large datasets were not closely inspected for the large-scale distributions & relationships among the researchers, resulting in the algorithms failing to scale well on the data. Therefore, this paper presents a novel TF algorithm for expert team formation called SSR-TF based on two metrics; communication cost and graph reduction, that will become a basis for future TF's. In SSR-TF, communication cost finds the possibility of collaboration between researchers. The graph reduction scales the large data to only appropriate skills and the experts, resulting in real-time extraction of experts for collaboration. This approach is tested on five organic and benchmark datasets, i.e., UMP, DBLP, ACM, IMDB, and Bibsonomy. The SSR-TF algorithm is able to build cost-effective teams with the most appropriate experts-resulting in the formation of more communicative teams with high expertise levels.
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Algoritmos , Comportamento Cooperativo , Rede Social , Gráficos por Computador , Heurística Computacional , Bases de Dados Factuais , Humanos , Filmes CinematográficosRESUMO
PURPOSE: Adequate knowledge, positive attitude, and proper practice of personal protective equipment by healthcare workers are necessary to get protection from COVID-19 infection. But this area is yet to be explored. Hence, we aimed to assess the knowledge, attitude, and practice (KAP) regarding personal protective equipment (PPE) among healthcare workers, along with a survey of the possible determinants. SUBJECTS AND METHODS: For this cross-sectional study, online and offline surveys were conducted among a sample of 393 healthcare workers from five different districts of Bangladesh. A validated self-administered questionnaire comprising five sections (socio-demography, work-related information, knowledge, attitude, and practice) was used for data collection. Multivariate stepwise forward logistic regression was applied to find significant factors associated with good attitude, and practice using SPSS version 25. RESULTS: The average age of the 393 participants was 28.9±5.2 years with a male-female ratio of one. Of them, 99.5% (n=391) had good knowledge, 88.8% (n=349) had positive attitude and 51.7% (n=203) had good practice regarding PPE. Results revealed that being a physician and living at home were significantly associated with a positive attitude. While being a non-physician, having lower education, working in private hospitals, and using office transport were associated with good practice regarding PPE. CONCLUSION: The findings demonstrated that the healthcare workers had an overall good knowledge and a positive attitude but a poor practice regarding PPE. This study also highlighted the factors influencing KAP towards PPE that must be addressed in future education, awareness, and counseling programs.
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Group A rotaviruses (RVA) remain a leading cause of pediatric diarrhea worldwide, in part due to underperformance of currently approved live-attenuated, oral vaccines in low-and-middle income countries. Improved immune correlates of protection (CoP) for existing oral vaccines and novel strategies to evaluate the performance of next-generation vaccines are needed. Use of oral vaccines as challenge agents in controlled human infection models is a potential approach to CoP discovery that remains underexplored. In a live-attenuated, oral rotavirus vaccine (Rotarix, GlaxoSmithKline) efficacy trial conducted among infants in Dhaka, Bangladesh, we explored the potential for the second dose of the two-dose series to be considered a challenge agent through which RVA immunity could be explored, using fecal virus shedding post-dose 2 as a marker of mucosal immunity. Among 180 vaccinated infants who completed the parent study per protocol, the absence of fecal vaccine shedding following the second dose of Rotarix suggested intestinal mucosal immunity generated by the first dose and a decreased risk of RVA diarrhea through 2 years of life (RR 0.616, 95% CI 0.392-0.968). Further development of controlled human infection models for group A rotaviruses, especially in prospective studies with larger sample sizes, may be a promising tool to assess rotavirus vaccine efficacy and CoPs.
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Imunidade nas Mucosas , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Administração Oral , Estudos de Coortes , Fezes/química , Humanos , Lactente , Rotavirus/imunologia , Vacinas contra Rotavirus/análise , Vacinas Atenuadas/análise , Vacinas Atenuadas/imunologiaRESUMO
Surface mining is a critical anthropogenic activity that significantly alters the ecosystem. Revegetation practices are largely utilized to compensate for these detrimental impacts of surface mining. In this study, we investigated the effects of five water (W) regimes [W40: 40%, W48: 48%, W60: 60%, W72: 72%, and W80: 80% of field capacity (FC)], five nitrogen (N) (N0: 0, N24: 24, N60: 60, N96: 96, and N120: 120 mg kg-1 soil), and five phosphorus (P) fertilizer doses (P0: 0, P36: 36, P90: 90, P144: 144, and P180: 180 mg kg-1 soil) on morpho-physiological and biochemical parameters of Ammopiptanthus mongolicus plants to assess the capability of this species to be used for restoration purposes. The results showed that under low W-N resources, A. mongolicus exhibited poor growth performance (i.e., reduced plant height, stem diameter, and dry biomass) in coal-degraded spoils, indicating that A. mongolicus exhibited successful adaptive mechanisms by reducing its biomass production to survive long in environmental stress conditions. Compared with control, moderate to high W and N-P application rates greatly enhanced the net photosynthesis rates, transpiration rates, water-use efficiency, chlorophyll (Chl) a, Chl b, total Chl, and carotenoid contents. Under low-W content, the N-P fertilization enhanced the contents of proline and soluble sugar, as well as the activities of superoxide dismutase, catalase, and peroxidase in leaf tissues, reducing the oxidative stress. Changes in plant growth and metabolism in W-shortage conditions supplied with N-P fertilization may be an adaptive strategy that is essential for its conservation and restoration in the desert ecosystem. The best growth performance was observed in plants under W supplements corresponding to 70% of FC and N and P doses of 33 and 36 mg kg-1 soil, respectively. Our results provide useful information for revegetation and ecological restoration in coal-degraded and arid-degraded lands in the world using endangered species A. mongolicus.
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Vitamin A deficiency remains a common public health problem among the rice-dependent poor people in the developing countries of Asia. Conventional milled rice does not contain provitamin A (ß-carotene) in is edible part (endosperm) and is also deficient in essential minerals, such as iron and zinc. Transgenic Golden Rice event GR2E, which produces ß-carotene in its endosperm, was used as a parent to introgress the transgene locus conferring ß-carotene biosynthesis into a widely grown rice variety, BRRI dhan29, which covers around 26.1% of the irrigated rice area (4.901 Mha) of Bangladesh in the dry season. The current study reports the introgression process and field performance of GR2E BRRI dhan29 Golden Rice. The background recovery of GR2E BRRI dhan29 lines at BC5F2 generation was more than 98% with a 6K SNP-chip set. The transgenic GR2E BRRI dhan29 yielded 6.2 t/ha to 7.7 t/ha with an average of 7.0 ± 0.38 t/ha, while the non-transgenic BRRI dhan29 yielded 7.0 t/ha under confined field conditions in Bangladesh. Moreover, no significant difference between GR2-E BRRI dhan29 Golden Rice and non-transgenic BRRI dhan29 in any measured trait was observed in the multi-location trials conducted at five locations across the country. Furthermore, the appearance of cooked and uncooked rice was similar to that of BRRI dhan29 except for the yellow color indicating the presence of carotenoids. Total carotenoid content in the selected introgression lines ranged from 8.5 to 12.5 µg/g with an average of 10.6 ± 1.16 µg/g. This amount is sufficient to deliver approximately 66 and 80% of the recommended daily intake of vitamin A for children and women, respectively, assuming complete substitution of white rice in the diet with Golden Rice. However, the lead selected line(s) need further evaluation at open field conditions before deciding for commercial cultivation. A large-scale feeding trial among the malnourished community with this newly developed GR2-E BRRI dhan29 Golden Rice is also required to validate its efficacy in alleviating vitamin A deficiency.
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Golden Rice with ß-carotene in the grain helps to address the problem of vitamin A deficiency. Prior to commercialize Golden Rice, several performance and regulatory checkpoints must be achieved. We report results of marker assisted backcross breeding of the GR2E trait into three popular rice varieties followed by a series of confined field tests of event GR2E introgression lines to assess their agronomic performance and carotenoid expression. Results from confined tests in the Philippines and Bangladesh have shown that GR2E introgression lines matched the performance of the recurrent parents for agronomic and yield performance, and the key components of grain quality. Moreover, no differences were observed in terms of pest and disease reaction. The best performing lines identified in each genetic background had significant amounts of carotenoids in the milled grains. These lines can supply 30-50% of the estimated average requirements of vitamin A.