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Global demand for food is increasing day by day due to an increase in population and shrinkage of the arable land area. To meet this increasing demand, there is a need to develop high-yielding varieties that are nutritionally enriched and tolerant against environmental stresses. Various techniques are developed for improving crop quality such as mutagenesis, intergeneric crosses, and translocation breeding. Later, with the development of genetic engineering, genetically modified crops came up with the transgene insertion approach which helps to withstand adverse conditions. The process or product-focused approaches are used for regulating genetically modified crops with their risk analysis on the environment and public health. However, recent advances in gene-editing technologies have led to a new era of plant breeding by developing techniques including site-directed nucleases, zinc finger nucleases, and the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) that involve precise gene editing without the transfer of foreign genes. But these techniques always remain in debate for their regulation status and public acceptance. The European countries and New Zealand, consider the gene-edited plants under the category of genetically modified organism (GMO) regulation while the USA frees the gene-edited plants from such type of regulations. Considering them under the category of GMO makes a long and complicated approval process to use them, which would decrease their immediate commercial value. There is a need to develop strong regulatory approaches for emerging technologies that expedite crop research and attract people to adopt these new varieties without hesitation.
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Sistemas CRISPR-Cas , Produtos Agrícolas , Regulamentação Governamental , Plantas Geneticamente Modificadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Produtos Agrícolas/economia , Produtos Agrícolas/genética , Edição de Genes/métodos , Engenharia Genética/métodos , Genoma de Planta , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas/classificação , Plantas Geneticamente Modificadas/genética , TransgenesRESUMO
In the quest to harness renewable energy sources for green hydrogen production, alkaline water electrolysis has emerged as a pivotal technology. Enhancing the reaction rates of overall water electrolysis and streamlining electrode manufacturing necessitate the development of bifunctional and cost-effective electrocatalysts. With this aim, a complex compound electrocatalyst in the form of cobalt-sulfo-boride (Co-S-B) was fabricated using a simple chemical reduction method and tested for overall alkaline water electrolysis. A nanocrystalline form of Co-S-B displayed a combination of porous and nanoflake-like morphology with a high surface area. In comparison to Co-B and Co-S, the Co-S-B electrocatalyst exhibits better bifunctional characteristics requiring lower overpotentials of 144 mV for hydrogen evolution reaction and 280 mV for oxygen evolution reaction to achieve 10 mA/cm2 in an alkaline electrolyte. The improved Co-S-B performance is attributed to the synergistic effect of sulfur and boron on cobalt, which was experimentally confirmed through various material characterization tools. Tafel slope, electrochemical surface area, turnover frequency, and charge transfer resistance further endorse the active nature of the Co-S-B electrocatalyst. The robustness of the developed electrocatalyst was validated through a 50 h chronoamperometric stability test, along with a recyclability test involving 10,000 cycles of linear sweep voltammetry. Furthermore, Co-S-B was tested in an alkaline zero-gap water electrolyzer, reaching 1 A/cm2 at 2.06 V and 60 °C. The significant activity and stability demonstrated by the cobalt-sulfo-boride compound render it as a promising and cost-effective electrode material for commercial alkaline water electrolyzers.
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Objective The objective of this study was to determine the antimicrobial activity of type III gypsum at three different chloramine-T concentrations and to ascertain the most effective concentration to be added for optimum inhibitory activity against Candida albicans. Method Ten discs of type III gypsum were fabricated for each group. Standard type III gypsum without any disinfectant was used for the control group. For the experimental group, an admixture of chloramine-T and standard dental stone was employed in varying w/w concentrations (0.1%, 0.25%, and 0.5%). Discs were placed in a petri dish containing Sabouraud dextrose agar lawned with Candida albicans culture and incubated for 24 hours. The zone of inhibition created around the discs was measured and evaluated. Result The mean zone of inhibition (mean ± standard deviation) in the control group was 0 mm; 0.70±1.05 mm in group 1 (0.1% w/w concentration), 2.70 ± 2.35 mm in group 2 (0.25% w/w concentration), and 20.80 ± 1.68 mm in group 3 (0.5% w/w concentration). A one-way ANOVA test showed that there was a significant difference in the inhibition zone created around all groups (p < 0.05), with the discs of group 3 yielding the most positive results. Conclusion The addition of 0.5% chloramine-T to type III gypsum showed the most promising result, out of the concentrations tested, as a self-disinfecting dental stone and could be used for further investigations.
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Both the rate of overall translation and the specific acceleration of proinsulin synthesis are known to be glucose-regulated processes in the beta-cell. In this study, we propose that glucose-induced stimulation of overall translation in beta-cells depends on a protein phosphatase-1-mediated decrease in serine-51 phosphorylation of eukaryotic translation initiation factor 2alpha (eIF2alpha), a pivotal translation initiation factor. The decrease was rapid and detectable within 15 min and proportional to the range of glucose concentrations that also stimulate translation. Lowered net eIF2alpha phosphorylation was not associated with a detectable decrease in activity of any eIF2alpha kinase. Moreover, okadaic acid blocked glucose-induced eIF2alpha dephosphorylation, suggesting that the net effect was mediated by a protein phosphatase. Experiments with salubrinal on intact cells and nuclear inhibitor of protein phosphatase-1 (PP1) on cell extracts suggested that this phosphatase was PP1. The net effect contained, however, a component of glucose-induced folding load in the endoplasmic reticulum because coincubation with cycloheximide further amplified the effect of glucose on eIF2alpha dephosphorylation. Thus, the steady-state level of eIF2alpha phosphorylation in beta-cells is the result of a balance between folding-load-induced phosphorylation and PP1-dependent dephosphorylation. Because defects in the pancreatic endoplasmic reticulum kinase-eIF2alpha signaling system lead to beta-cell failure and diabetes, deregulation of the PP1 system could likewise lead to cellular dysfunction and disease.
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Fator de Iniciação 2 em Eucariotos/metabolismo , Glucose/farmacologia , Células Secretoras de Insulina/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Cicloeximida/farmacologia , Sinergismo Farmacológico , Retículo Endoplasmático/metabolismo , Ativação Enzimática , Homeostase/fisiologia , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Dobramento de Proteína , Proteína Fosfatase 1 , Inibidores da Síntese de Proteínas/farmacologia , Proteínas/metabolismo , eIF-2 Quinase/metabolismoRESUMO
Replacement of single missing tooth in the aesthetic region presents a challenge for a dentist.1 Various treatment considerations have to be dealt before decision making. Treatment options for such cases are removable partial denture, conventional or resin - bonded fixed partial denture (FPD), and implant-supported fixed prosthesis. Each modality is a possible treatment option and has its advantages and disadvantages.2,3 The treatment option selected would depend on patients’ age, desires, compliance, also the treatment cost, adjacent teeth conditions, bone availability and aesthetics being of prime concern. However, it is found that implant-supported crown is the most preferred option in case of single missing tooth in the aesthetic zone.2,4,5 Implants besides being advantageous over resin-bonded or traditional fixed partial dentures, they also prevent the unnecessary restoration on the adjacent sound teeth as required in an FPD. Hence, implants help in saving the integrity of the existing tooth in situations where the adjacent tooth is vital and have no restorations.2 Also, many authors have suggested implant as a predictable treatment option in case of single tooth replacement.6,7The success of implant is not only defined by the Osseo integration achieved but also its proper placement and with harmonious and naturally blending prosthesis.8 Yet sometimes, there may be situations wherein misaligned placement of implant and reduced interarch space for future prosthesis may pose a challenge for the Prosthodontist, especially in aesthetic zone. Methods like angulated abutments, castable abutments or in severe cases even removable prosthesis have been suggested to surmount such complications.4 The following article presents with two such case scenarios dental implants were restored with castable abutment.Restoration of missing teeth in aesthetic zone is of concern for any individual. Treatment options like removable partial denture, fixed partial denture or implant retained prosthesis can be opted. The treatment option selected would depend on patients’ age, desires, compliance, also the treatment cost, adjacent teeth conditions, bone availability and aesthetics being of prime concern.Keeping in mind the patients’ age bone and periodontal conditions, implant-supported crown is the most preferred option in case of single missing tooth in the aesthetic zone. The success of implant is not only defined by osseointegration achieved, but also its proper placement and with harmonious and naturally blending prosthesis. Yet sometimes, there may be situations wherein misaligned placement of implant and reduced interarch space for future prosthesis may pose a challenge for the prosthodontist, especially in the aesthetic zone. In such complex cases, restoration with a customized treatment plan has to be carried out in order to fulfil patients’ aesthetic requirement as well as restore the implant with a fixed prosthesis. The following article presents with two such case scenarios where the misaligned dental implant placed and the other with reduced interarch space were restored with castable abutment.
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AIM: To determine if other molecules reported to modulate AMP-dependent protein kinase (AMPK) activity would have effects resembling those of metformin and phenformin on colon cancer cell proliferation and metabolism. METHODS: Studies were performed with four human colon cancer cell lines, Caco-2, HCT116, HT29 and SW1116. The compounds that were studied included A-769662, 5-aminoimidazole-4-carboxamide-1-ribofuranoside, butyrate, (-)-epigallocatechin gallate (EGCG), KU-55933, quercetin, resveratrol and salicylates. The parameters that were measured were cell proliferation and viability, glucose uptake, lactate production and acidification of the incubation medium. RESULTS: Investigations with several molecules that have been reported to be associated with AMPK activation (A-769662, 5-aminoimidazole-4-carboxamide-1-b-D-ribofuranoside, EGCG, KU-55933, quercetin, resveratrol and salicylates) or AMPK inhibition (compound C) failed to reveal increased medium acidification and increased glucose uptake in colon cancer cells as previously established with metformin and phenformin. The only exception was 5-aminosalicylic acid with which there were apparently lower glucose levels in the medium after incubation for 72 h. Further study in the absence of cells revealed that the effect was an artifact due to inhibition of the enzyme-linked glucose assay. The compounds were studied at concentrations that inhibited cell proliferation. CONCLUSION: It was concluded that treatment with several agents that can affect AMPK activity resulted in the inhibition of the proliferation of colon cancer cells under conditions in which glucose metabolism is not enhanced, in contrast to the effect of biguanides.
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Men who have sex with men (MSM) are at particular risk for HIV/sexually transmitted infections (STI). To investigate the European guidance used for MSM STI and HIV screening, risk level profiling and how this translated to practice, we conducted a questionnaire survey of leading physicians in the European branch of the International Union against Sexually Transmitted Infections (IUSTI). We identified that most European countries have limited guidance on screening intervals for MSM. Where risk profiling is advised, it is often left to clinicians to weight different behaviours and decide on screening frequency. Our results suggest that European MSM STI and HIV testing guidelines be developed with clear and specific recommendations around screening intervals and risk profiling. These guidelines will be particularly helpful due to rapidly evolving models of sexual healthcare, and the emergence of new providers who may benefit from guidelines that require less interpretation.
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Infecções por HIV/diagnóstico , Homossexualidade Masculina/estatística & dados numéricos , Programas de Rastreamento/métodos , Guias de Prática Clínica como Assunto , Infecções Sexualmente Transmissíveis/diagnóstico , Adolescente , Adulto , Diagnóstico Precoce , Europa (Continente)/epidemiologia , Infecções por HIV/epidemiologia , Comportamentos Relacionados com a Saúde , Pesquisa sobre Serviços de Saúde , Inquéritos Epidemiológicos , Homossexualidade Masculina/psicologia , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Programas de Rastreamento/tendências , Prevalência , Medição de Risco , Assunção de Riscos , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários , Adulto JovemRESUMO
As the molecular processes of complex cell stress signaling pathways are defined, the subsequent challenge is to elucidate how each individual event influences the final biological outcome. Phosphorylation of the translation initiation factor 2 (eIF2alpha)atSer(51) is a molecular signal that inhibits translation in response to activation of any of four diverse eIF2alpha stress kinases. We used gene targeting to replace the wild-type Ser(51) allele with an Ala in the eIF2alpha gene to test the hypothesis that translational control through eIF2alpha phosphorylation is a central death stimulus in eukaryotic cells. Homozygous eIF2alpha mutant mouse embryo fibroblasts were resistant to the apoptotic effects of dsRNA, tumor necrosis factor-alpha, and serum deprivation. TNFalpha treatment induced eIF2alpha phosphorylation and activation of caspase 3 primarily through the dsRNA-activated eIF2alpha kinase PKR. In addition, expression of a phospho-mimetic Ser(51) to Asp mutant eIF2alpha-activated caspase 3, indicating that eIF2alpha phosphorylation is sufficient to induce apoptosis. The proapoptotic effects of PKR-mediated eIF2alpha phosphorylation contrast with the anti-apoptotic response upon activation of the PKR-related endoplasmic reticulum eIF2alpha kinase, PERK. Therefore, divergent fates of death and survival can be mediated through phosphorylation at the same site within eIF2alpha. We propose that eIF2alpha phosphorylation is fundamentally a death signal, yet it may promote either death or survival, depending upon coincident signaling events.
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Apoptose , Fator de Iniciação 2 em Eucariotos/fisiologia , eIF-2 Quinase/química , Animais , Caspase 3 , Caspases/metabolismo , Linhagem Celular , DNA/química , Células HeLa , Homozigoto , Humanos , Camundongos , Fosforilação , RNA de Cadeia Dupla/química , TransfecçãoRESUMO
The double-stranded (ds) RNA-activated protein kinase (PKR) plays an important role in control of viral infections and cell growth. We have studied the role of PKR in viral infection in mice that are defective in the PKR signaling pathway. Transgenic mice were derived that constitutively express a trans-dominant-negative kinase-defective mutant PKR under control of the beta-actin promoter. The trans-dominant-negative PKR mutant expressing transgenic mice do not have a detectable phenotype, similar to observations with PKR knock-out mice. The requirement for PKR in viral pathogenesis was studied by intracerebral infection of mice with a mouse-adapted poliovirus. Histopathological analysis revealed diffuse encephalomyelitis with severe inflammatory lesions throughout the central nervous system (CNS) in infected wild-type mice. In contrast, histopathological evaluation of virus-injected trans-dominant-negative PKR transgenic mice as well as PKR knock-out mice yielded no signs of tissue damage associated with inflammatory host responses. However, the virus did replicate in both models of PKR-deficient mice at a level equal to that observed in wild-type infected mice. Although the results indicate a clear difference in susceptibility to poliovirus-induced encephalitis, this difference manifests clinically as a slight delay in fatal neuropathy in trans-dominant-negative PKR transgenic and PKR knock-out animals. Our observations support the finding that viral-induced PKR activation may play a significant role in pathogenesis by mediating the host response to viral CNS infection. They support PKR to be an effective target to control tissue damage due to deleterious host responses to viral infection.