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The outbreak of the current coronavirus disease (COVID-19) occurred in late 2019 and quickly spread all over the world. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) belongs to a genetically diverse group that mutates continuously leading to the emergence of multiple variants. Although a few antiviral agents and anti-inflammatory medicines are available, thousands of individuals have passed away due to emergence of new viral variants. Thus, proper surveillance of the SARS-CoV-2 genome is needed for the rapid identification of developing mutations over time, which are of the major concern if they occur specifically in the surface spike proteins of the virus (neutralizing analyte). This article reviews the potential mutations acquired by the SARS-CoV2 since the pandemic began and their significant impact on the neutralizing efficiency of vaccines and validity of the diagnostic assays.
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COVID-19/epidemiologia , Deriva Genética , Genoma Viral/genética , RNA Viral/genética , SARS-CoV-2/genética , Anticorpos Neutralizantes/imunologia , Frequência do Gene/genética , Variação Genética/genética , Humanos , Imunogenicidade da Vacina/imunologia , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
Bacteriocins exhibited a wide spectrum of antibacterial activity against different pathogens. The aim of current study was to characterize the bacteriocins produced by Bifidobacterium spp. isolated from ruminants. The Bifidobacterium isolates were identified as B. longum, B. pseudolongum, B. bifidum, B. thermophilum, B. boum, B. merycicum and B. ruminantium. Bacteriocins were found to be pH stable, heat resistant, highly diffusible, NaCl tolerant and resistant to UV radiations. SDS, EDTA and urea induced 14%, 21% and 24% bacteriocins activity loss. Modified MRS broth (1% tryptone, 1% yeast extract and 2% glucose) was found to be the best nutrient medium for optimal production of bacteriocins. Minimum inhibitory concentration (MIC) values varied from 300 µl/ml to 500 µl/ml and minimum bactericidal concentration (MBC) values ranged from 500 µl/ml to >500 µl/ml for E. coli and S. aureus respectively. The highest protein concentration (29.0248 mg/ml) was recorded for Bifidobacteria bacteriocin produced by B. longum. Tricine-Sodium Dodecyl Sulfate-Poly Acrylamide Gel Electrophoresis (SDS-PAGE) revealed that molecular weight of isolated bifidobacterial bacteriocins was in the range of 3.6 kDa-30 kDa. Current study indicated that bifidobacterial bacteriocins have considerable potential to be used as biopreservative.
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Bacteriocinas , Bifidobacterium , Ruminantes , Animais , Acrilamidas , Antibacterianos/farmacologia , Antibacterianos/química , Bacteriocinas/farmacologia , Bacteriocinas/química , Ácido Edético , Escherichia coli , Glucose , Concentração de Íons de Hidrogênio , Ruminantes/microbiologia , Cloreto de Sódio , Dodecilsulfato de Sódio , Staphylococcus aureus , UreiaRESUMO
Some soil microbes, with their diverse inhabitance, biologically active metabolites, and endospore formation, gave them characteristic predominance and recognition among other microbial communities. The present study collected ten soil samples from green land, agricultural and marshy soil sites of Khyber Pakhtunkhwa, Pakistan. After culturing on described media, the bacterial isolates were identified through phenotypic, biochemical and phylogenetic analysis. Our phylogenetic analysis revealed three bacterial isolates, A6S7, A1S6, and A1S10, showing 99% nucleotides sequence similarity with Brevibacillus formosus, Bacillus Subtilis and Paenibacillus dendritiformis. The crude extract was prepared from bacterial isolates to assess the anti-bacterial potential against various targeted multidrug-resistant strains (MDRS), including Acinetobacter baumannii (ATCC 19606), Methicillin-resistant Staphylococcus aureus (MRSA) (BAA-1683), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (BAA-2108), Staphylococcus aureus (ATCC 292013), Escherichia coli (ATCC25922) and Salmonella typhi (ATCC 14028). Our analysis revealed that all bacterial extracts possess activity against Gram-negative and Gram-positive bacteria at a concentration of 5 mg/mL, efficiently restricting the growth of E. coli compared with positive control ciprofloxacin. The study concluded that the identified species have the potential to produce antimicrobial compounds which can be used to control different microbial infections, especially MDRS. Moreover, the analysis of the bacterial extracts through GC-MS indicated the presence of different antimicrobial compounds such as propanoic acid, oxalic acid, phenol and hexadecanoic acid.
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Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina , Misturas Complexas , Escherichia coli , Testes de Sensibilidade Microbiana , Nucleotídeos , Ácido Oxálico , Ácido Palmítico , Fenóis , Filogenia , Propionatos , SoloRESUMO
Medicinal plants play important role in the public health sector worldwide. Natural products from medicinal plants are sources of unlimited opportunities for new drug leads because of their unique chemical diversity. Researchers have focused on exploring herbal products as potential sources for the treatment of cancer, cardiac and infectious diseases. Arisaema flavum (Forssk.) is an important medicinal plant found in the northwest Himalayan regions of Pakistan. It is a poisonous plant and is used as a remedy against snake bites and scorpion stings. In this study, two bioactive compounds were isolated from Arisaema flavum (Forssk.) and their anticancer activity was evaluated against human breast cancer cell line MCF-7 using an MTT assay. The crude extract of Arisaema flavum (Forssk.) was subjected to fractionation using different organic solvents in increasing order of polarity. The fraction indicating maximum activity was then taken for isolation of bioactive compounds using various chromatographic and spectroscopic techniques such as column chromatography, thin-layer chromatography (TLC), gas chromatography−mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Crude extract of Arisaema flavum (Forssk.), as well as various fractions extracted in different solvents such as n-hexane, chloroform and ethyl acetate, were tested against human breast cancer cell line MCF-7 using an MTT assay. The crude extract exhibited significant dose-dependent anticancer activity with a maximum activity of 78.6% at 500 µg/mL concentration. Two compounds, hexadecanoic acid ethyl ester with molecular formula C18H36O7 and molar mass 284 and 5-Oxo-19 propyl-docosanoic acid methyl ester with molecular formula C26H50O3 and molecular mass 410, were isolated from chloroform fraction. These compounds were tested against the MCF-7cell line for cytotoxic activity and exhibited a significant (p < 0.00l) decrease in cell numbers for MCF-7 cells with IC50 of 25 µM after 48 h of treatment. Results indicated that Arisaema flavum (Forssk.) possesses compounds with cytotoxic activity that can further be exploited to develop anticancer formulations.
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Antineoplásicos , Arisaema , Neoplasias da Mama , Plantas Medicinais , Humanos , Feminino , Extratos Vegetais/química , Clorofórmio , Plantas Medicinais/química , Cromatografia em Camada Fina , Antineoplásicos/farmacologia , Solventes , ÉsteresRESUMO
Soybean plants require high amounts of nitrogen, which are mainly obtained from biological nitrogen fixation. A field experiment was conducted by soybean (Glycine max) genotypes, growing two varieties (Shohag and BARI Soybean6) and two advanced lines (MTD10 and BGM02026) of soybean with or without Rhizobium sp. BARIRGm901 inoculation. Soybean plants of all genotypes inoculated with Rhizobium sp. BARIRGm901 produced greater nodule numbers, nodule weight, shoot and root biomass, and plant height than non-inoculated plants. Similarly, inoculated plants showed enhanced activity of nitrogenase (NA) enzyme, contributing to higher nitrogen fixation and assimilation, compared to non-inoculated soybean plants in both years. Plants inoculated with Rhizobium sp. BARIRGm901 also showed higher pod, stover, and seed yield than non-inoculated plants. Therefore, Rhizobium sp. BARIRGm901 established an effective symbiotic relationship with a range of soybean genotypes and thus increased the nodulation, growth, and yield of soybean grown in gray terrace soils in Bangladesh.
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Glycine max/microbiologia , Filogenia , Nodulação/fisiologia , Raízes de Plantas/microbiologia , Rhizobium/genética , Microbiologia do Solo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biomassa , Expressão Gênica , Genótipo , Nitrogênio/metabolismo , Fixação de Nitrogênio/fisiologia , Nitrogenase/genética , Nitrogenase/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta , RNA Ribossômico 16S/genética , Rhizobium/classificação , Rhizobium/enzimologia , Rhizobium/crescimento & desenvolvimento , Glycine max/crescimento & desenvolvimento , Glycine max/metabolismo , Simbiose/fisiologiaRESUMO
Inflammatory bowel disease (IBD) is a chronic autoimmune condition that can have a wide range of symptoms among pediatric patients. Although clinical symptoms like hematochezia, diarrhea, and abdominal pain are commonly addressed, health-related quality of life (HRQOL) is often overlooked in patients with IBD and pediatric patients with chronic disease in general. Examining HRQOL can help improve patient outcomes, but it has been studied sparingly. In this review, we aim to compare HRQOL between pediatric patients suffering from IBD and healthy children, as well as those suffering from other illnesses. We searched through peer-reviewed primary literature related to IBD and HRQOL and selected 10 articles from the PubMed database to be reviewed. Our inclusion criteria included articles published after the year 2000 in English, primary studies, and those that corresponded to the aim of this review. Case reports and secondary and tertiary articles were excluded from our review. We found that patients with IBD reported worse HRQOL in terms of overall health and in various subdomains, including physical health and fatigue, compared to their healthy counterparts. However, children with IBD demonstrated a comparable HRQOL with children suffering from functional abdominal pain (FAP) and obesity. Additionally, children with IBD displayed a greater HRQOL than pediatric patients with gastroesophageal reflux disease (GERD) and chronic constipation. In addressing the aim of this review, we found that children with IBD had a lower HRQOL when compared to healthy children, but a comparable or greater HRQOL than other sick children. Some factors associated with a reduced HRQOL include disease activity, age, fatigue, gender, psychological variables, and associated symptoms. Going forward, HRQOL should be considered by practitioners when caring for pediatric IBD patients in a clinical setting as it can help improve patient care. More studies need to be conducted to further explore HRQOL in pediatric patients. This can help implement early psychosocial interventions in children to reduce the disease burden.
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The COVID-19 being a preconized global pandemic by the World Health Organization needs persuasive immediate research for possible medications. The present study was carried out with a specific aim to computationally evaluate and identify compounds derived from Bacillus species as the plausible inhibitors against 3-chymotrypsin-like main protease (3CLpro) or main protease (MPro), which is a key enzyme in the life-cycle of coronavirus. The compounds were isolated from the crude extracts of Bacillus species. Among the isolated compounds, novel inhibitory leads were identified using in silico techniques. Molecular docking revealed that stigmasterol (-8.3 kcal/mol), chondrillasterol (-7.9 kcal/mol) and hexadecnoic acid (-6.9 kcal/mol)) among others bind in the substrate-binding pocket and also interacted with the catalytic dyad of the 3-CLpro. Further evaluation using 50 ns molecular dynamic simulation and MMPB-GBSA indicated that among the top three docking hits, hexadecanoic acid was found to be the most promising anti-COVID-19 lead against the main protease. Hexadecanoic acid might serve as a potent anti-SARS-CoV-2 compound to combat COVID-19, however, in vitro and in vivo validation and optimization is needed.Communicated by Ramaswamy H. Sarma.
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Bacillus , Tratamento Farmacológico da COVID-19 , Bacillus/metabolismo , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ácido Palmítico , Inibidores de Proteases/química , Inibidores de Proteases/farmacologiaRESUMO
BACKGROUND AND OBJECTIVES: Family-centered rounds (FCR) can lead to improved communication, satisfaction, and care delivery. However, FCR are variable in practice. Our primary goal was to implement and sustain consistent communication practices during FCR (a subset of all rounds in which parents were present) for patients on a pediatric hospital medicine service. We aimed to achieve 80% reliability for the following FCR practices: (1) discussion of risk factors and prevention strategies for hospital-acquired conditions (HACs), (2) discussion of discharge planning, and (3) asking families for questions. METHODS: Research assistants observed FCR on a pediatric acute care unit at an academic medical center and recorded if the rounding team discussed HAC risk factors, discussed discharge, or asked families for questions. Using the Model for Improvement, we performed multiple plan-do-study-act cycles to test and implement interventions, including (1) standardized note templates, (2) education via peer-led group discussions and team e-mails, and (3) routine provider feedback about performance. Data were analyzed by using statistical process control charts. RESULTS: From October 2017 to April 2019, reliability increased to >80% and sustained for (1) discussion of HAC risk factors (increased from 11% to 89%), (2) discussion of discharge planning (from 60% to 92%), and (3) asking families for questions (from 61% to 87%). Peer-led physician education, reminder e-mails, and physician engagement were the most impactful interventions corresponding to centerline shifts. CONCLUSIONS: Using multiple interventions, we achieved and sustained improvements in key communication-related elements of FCR. Future work will focus on determining if improved practices impact clinical outcomes.
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Melhoria de Qualidade , Visitas de Preceptoria , Criança , Comunicação , Humanos , Relações Profissional-Família , Reprodutibilidade dos TestesRESUMO
The acquisition of multi-drug resistance (MDR) genes by pathogenic bacterial bugs and their dispersal to different food webs has become a silent pandemic. The multiplied use of different antibacterial therapeutics during COVID-19 pandemic has accelerated the process among emerging pathogens. Wild migratory birds play an important role in the spread of MDR pathogens and MDR gene flow due to the consumption of contaminated food and water. Escherichia fergusonii is an emerging pathogen of family Enterobacteriaceae and commonly causes disease in human and animals. The present study focused on the isolation of E. fergusonii from blood, saliva, and intestine of selected migratory birds of the Hazara Division. The sensitivity of isolated strains was assessed against ten different antibiotics. The isolation frequency of E. fergusonii was 69%. In blood samples, a high rate of resistance was observed against ceftriaxone (80%) followed by ampicillin (76%) whereas, in oral and intestinal samples, ceftriaxone resistant strains were 56% and 57% while ampicillin resistance was 49% and 52% respectively. The overall ceftriaxone and ampicillin-resistant cases in all three sample sources were 71% and 65% respectively. In comparison to oral and intestinal samples, high numbers of ceftriaxone-resistant strains were isolated from the blood of mallard while ampicillin-resistant strains were observed in blood samples of cattle egrets. 16S rRNA-based confirmed strains of E. fergusonii were processed for detection of CTX-M and TEM-1 gene through Polymerase chain reaction (PCR) after DNA extraction. Hundred percent ceftriaxone resistant isolates possessed CTX-M and all ampicillin-resistant strains harbored TEM-1 genes. Amplified products were sequenced by using the Sanger sequencing method and the resulted sequences were checked for similarity in the nucleotide Database through the BLAST program. TEM-1 gene showed 99% and the CTX-M gene showed 98% similar sequences in the Database. The 16S rRNA sequence and nucleotide sequences for TEM-1 and CTX-M genes were submitted to Gene Bank with accession numbers LC521304, LC521306, LC521307 respectively. We posit to combat MDR gene flow among the bacterial pathogens across different geographical locations, regular surveillance of new zoonotic pathogens must be conducted.
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Salmonella enterica serovar Typhi is Gram negative, rod shaped, facultative anaerobic bacterium, belongs to enterobacteriaceae family that causes typhoid fever in humans. This bacterium has become a super bug due to acquisition of multi drug resistance. Bacteria is transmitted through food and water contaminated with human feaces. Present study reports the screening of Adhatoda vasica, Amaranthus hybridus and Aloe barbadensis and their evaluation against multi-drug resistant Salmonella enterica serovar Typhi. Qualitative analysis of ten phytochemicals was conducted using chemical method and Gas Chromatography-Mass Spectrometry (GCMS). Antibacterial activity of plants was carried out by agar well diffusion method on Mueller Hinton agar. Total tannins, total alkaloids and total flavonoids of different parts of three plants were estimated through spectrophotometer. Total tannins content in different parts of plants was present in the given order Amaranthus hybridus leaf > Aloe barbadensis leaf > Adhatoda vasica leaf > Adhatoda vasica flower > Adhatoda vasica stem. Whereas, the order of total flavonoid concentration was Amaranthus hybridus leaf > Aloe barbadensis leaf > Adhatoda vasica leaf > Amaranthus hybridus seed. Total alkaloids have order, Adhatoda vasica leaf > Amaranthus hybridus leaf > Adhatoda vasica flower > Amaranthus hybridus seed > Aloe barbadensis leaf. Results of phytochemical analysis suggested that plants have strong profile of antioxidants, total phenolic contents and various enzymes proposing them best alternate to cure bacterial infections. GC-MS analysis further confirmed stronger phytochemical profile that can be utilized as antagonists to Salmonella enterica serovar Typhi.
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Zearalenone (ZEA) is a secondary metabolite produced by Fusarium spp., the filamentous fungi. Food and feed contamination with zearalenone has adverse effects on health and economy. ZEA degradation through microorganisms is providing a promising preventive measure. The current study includes isolation of 47 bacterial strains from 100 different food and rumen samples. Seventeen isolates showed maximum activity of ZEA reduction. A bacterial isolate, RS-5, reduced ZEA concentration up to 78.3% through ELISA analysis and 74.3% as determined through HPLC. Ten of the most efficient strains were further selected for comparison of their biodegradation activity in different conditions such as incubation period, and different growth media. The samples were analyzed after 24 h, 48 h, and 72 h of incubation. De Man Rogosa Sharp (MRS) broth, Tryptic soy broth, and nutrient broth were used as different carbon sources for comparison of activity through ELISA. The mean degradation % ± SD through ELISA and HPLC were 70.77% ± 3.935 and 69.11% ± 2.768, respectively. Optimum reducing activity was detected at 72 h of incubation, and MRS broth is a suitable medium. Phylogenetic analysis based on 16S rRNA gene nucleotide sequences confirmed that one of the bacterial isolate RS-5 bacterial isolates with higher mycotoxin degradation is identified as Bacillus subtilis isolated from rumen sample. B05 (FSL-8) bacterial isolate of yogurt belongs to the genus Lactobacillus with 99.66% similarity with Lactobacillus delbrukii. Similarly, three other bacterial isolates, D05, H05 and F04 (FS-17, FSL-2 and FS-20), were found to be the sub-species/strains Pseudomonas gessardii of genus Pseudomonas based on their similarity level of (99.2%, 96% and 96.88%) and positioning in the phylogenetic tree. Promising detoxification results were revealed through GC-MS analysis of RS-5 and FSL-8 activity.
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Bacillus subtilis/metabolismo , Lactobacillus/metabolismo , Pseudomonas/metabolismo , Zearalenona/metabolismo , Bacillus subtilis/efeitos dos fármacos , Biotransformação , Microbiologia de Alimentos , Lactobacillus/efeitos dos fármacos , Pseudomonas/efeitos dos fármacosRESUMO
This molecular epidemiological study was designed to determine the antimalarial drug resistance pattern, and the genetic diversity of malaria isolates collected from a war-altered Federally Administered Tribal Area (FATA), in Pakistan. Clinical isolates were collected from Bajaur, Mohmand, Khyber, Orakzai and Kurram agencies of FATA region between May 2017 and May 2018, and they underwent DNA extraction and amplification. The investigation of gene polymorphisms in drug resistance genes (dhfr, dhps, crt, and mdr1) of Plasmodium falciparum and Plasmodium vivax was carried out by pyrosequencing and Sanger sequencing, respectively. Out of 679 PCR-confirmed malaria samples, 523 (77%) were P. vivax, 121 (18%) P. falciparum, and 35 (5%) had mixed-species infections. All P. falciparum isolates had pfdhfr double mutants (C59R+S108N), while pfdhfr/pfdhps triple mutants (C59R+S108N+A437G) were detected in 11.5% of the samples. About 97.4% of P. falciparum isolates contained pfcrt K76T mutation, while pfmdr1 N86Y and Y184F mutations were present in 18.2% and 10.2% of the samples. P. vivax pvdhfr S58R mutation was present in 24.9% of isolates and the S117N mutation in 36.2%, while no mutation in the pvdhps gene was found. Pvmdr1 F1076L mutation was found in nearly all samples, as it was observed in 98.9% of isolates. No significant anti-folate and chloroquine resistance was observed in P. vivax; however, mutations associated with antifolate-resistance were found, and the chloroquine-resistant gene has been observed in 100% of P. falciparum isolates. Chloroquine and sulphadoxine-pyrimethamine resistance were found to be high in P. falciparum and low in P. vivax. Chloroquine could still be used for P. vivax infection but need to be tested in vivo, whereas a replacement of the artemisinin combination therapy for P. falciparum appears to be justified.
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Antimaláricos , Malária Falciparum , Antimaláricos/farmacologia , Resistência a Medicamentos/genética , Humanos , Mutação , Paquistão , Plasmodium falciparum/genética , Plasmodium vivax/genética , Proteínas de Protozoários/genéticaRESUMO
Rice bran oil is known as wonder oil and it is the most important vegetable oil in Asia. Rice bran oil is extracted from bran that is the outer hard layer of rice. It is an emerging category in edible oil with a lot of nutritional properties and health benefits. Rice bran oil is heart-friendly, boosts up immunity, and prevents from other diseases occurring commonly in Pakistan. The current study aimed to stabilize rice bran oil through different probiotic isolates and to assess the nutritional content of rice bran oil after stabilization. The study was aimed to inactivate naturally occurring lipases that can hydrolyze oil into glycerol and free fatty acid which is a serious problem that gives it a rancid taste and smell. Antilipase activity was used to inactivate naturally occurring lipases that are a huge threat to the stabilization process. The fermentation process utilizes antilipase activity without affecting the nutritional value of oil. Lactobacillus strains were used for the stabilization of rice bran oil. Rice bran oil was extracted in the Soxhlet apparatus. The probiotic lab isolates Lactobacillus delbrueckii S2, Lactobacillus casei S5 and Lactobacillus plantarum S13 were applied to it to increase its shelf life and prevent oxidative rancidity. The extraction temperature of rice bran oil was maintained above 40 °C to inhibit lipase activity. Rice bran oil samples were stored at refrigeration temperature to arrest lipase activity. Probiotics maintained acidic pH to keep oil stabilization. Qualitative analysis was done to confirm rice bran oil stabilization. Determination of Free Fatty Acid (FFA) and saponification value confirmed that oxidative rancidity of rice bran oil was controlled by probiotics. FFA count was less than 10% and Saponification Value (SV) was 180. GC analysis was performed to analyze the FFA profile. Gas Chromatography results have shown 3 fatty acids. Statistical analysis has shown non-significant effect on different incubation temperatures of Lactobacillus isolates. Among the biological methods of stabilization, the use of probiotics is a novel concept and recommended for commercial application.
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The current study focuses on the usage of bio synthesized zinc oxide nanoparticles to increase the tissue culture efficiency of important forage grass Panicum virgatum. Zinc being a micronutrient enhanced the callogenesis and regeneration efficiency of Panicum virgatum at different concentrations. Here, we synthesized zinc oxide nanoparticles through Cymbopogon citratus leaves extract to evaluate the effect of zinc oxide nanoparticles on plant regeneration ability in switchgrass. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) validate phase purity of green synthesize Zinc oxide nanoparticles whereas, electron microscopy (SEM) has illustrated the average size of particle 50±4 nm with hexagonal rod like shape. Energy dispersive spectroscopy X-ray (EDS) depicted major peaks of Zn (92.68%) while minor peaks refer to Oxygen (7.32%). ZnO-NPs demonstrated the incredibly promising results against callogenesis. Biosynthesized ZnO-NPs at optimum concentration showed very promising effect on plant regeneration ability. Both the explants, seeds and nodes showed dose dependent response and upon high doses exceeding 40 mg/L the results were recorded negative, whereas at 30 mg/L both explants demonstrated 70% and 76% regeneration frequency. The results conclude that ZnO-NPs enhance the plant growth and development and tailored the nutritive properties at nano-scale. Furthermore, eco-friendly approach of ZnO-NPs synthesis is strongly believed to improve in vitro regeneration frequencies in several other monocot plants.
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Nanopartículas Metálicas , Panicum/efeitos dos fármacos , Panicum/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Óxido de Zinco/farmacologia , Cymbopogon , Nanopartículas Metálicas/ultraestrutura , Regeneração , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Óxido de Zinco/síntese químicaRESUMO
INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are rare. Nevertheless, some may present with a life-threatening hemorrhage or intestinal obstruction. The aim of this study was to review the various modes of the presentation of GIST, especially hemorrhage and obstruction, and to assess the role of laparoscopic surgery in the management of acute cases and the correlation of such cases with malignant potential. METHODS: Data were collected from the hospital in the patient records as well as a prospective database. Their presentation, management, histologic features, and follow-up periods were analyzed. RESULTS: Nine cases of GIST were collected. Five (56%) presented with hemorrhage, 3 (33%) with intestinal obstruction, and 1 (11%) with a tender epigastric mass. Six patients had a gastroscopy procedure, and 6 had a computed tomography scan of the abdomen and pelvis. Five (67%) patients underwent a partial gastrectomy (3 laparoscopic and 2 open procedures), 1 had a laparoscopic localized resection of a gastric GIST, and 3 (33%) had a resection and anastomosis of the bowel. All patients presented acutely, and 78% had emergency surgery performed. The laparoscopic approach was attempted in 6 patients (67%), and was successful in 4 (67%). All patients who had a laparoscopic treatment performed had less pain, a quicker recovery, and a shorter hospital stay, as compared to those patients who had open surgery. Five cases were malignant tumors. Immunohistochemistry revealed a positive c-kit and CD34 for all tumors. The median follow-up was 24 months with one recurrence. CONCLUSIONS: Our experience showed that GISTs can present acutely and may need immediate surgical intervention. A laparoscopic treatment is safe and practical in experienced hands. Tumor size and hemorrhage at presentation can predict a patient's malignant potential.
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Tumores do Estroma Gastrointestinal/cirurgia , Laparoscopia/métodos , Neoplasias Gástricas/cirurgia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/complicações , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Prospectivos , Neoplasias Gástricas/complicações , Resultado do TratamentoRESUMO
NADPH-dependent thioredoxin reductases (NTRs) are key-regulatory enzymes determining the redox state of the thioredoxin (Trx) system that provides reducing power to peroxidases or oxidoreductases. Moreover, it also plays an essential function in the direct reduction of ROS and acquiring stress tolerance in plant. Cytoplasmic NTRA, mitochondrial NTRB, and chloroplastic NTRC are the three conserved NTRs which cooperate with specific sub-cellularly localized Trxs in Arabidopsis. However, cytosolic NTRs such as NTRA in Arabidopsis have not previously been identified in plants or mammals as a source of functional redundancy with mitochondrial NTRs. Here, we show the involvement of NTRA in the plant stress response counteracting oxidative and drought stresses. Methyl viologen (MV), an inducer of oxidative stress in plants, enhanced the NTRA transcripts. To identify the physiological role of NTRA influencing ROS homeostasis by stress, NTRA overexpression (NTRAOX) and knock-out mutants (ntra-ko) were generated. After exposure to oxidative stress, wild-type and ntra-ko plants were sensitive, but NTRAOX plants tolerant. ROS range was increased by MV in wild-type and ntra-ko plants, but not in NTRAOX. Investigating the involvement of Arabidopsis NTRA in drought, NTRAOX plants exhibited extreme drought tolerance with high survival rates, lower water loss and reduced ROS compared to wild-type and ntra-ko plants. Transcripts of drought-responsive genes, such as RD29A and DREB2A, were highly expressed under drought and antioxidant genes, namely CuZnSOD and APX1 were enhanced in the absence of drought in NTRAOX plants. The results suggest that NTRA overexpression confers oxidative and drought tolerance by regulation of ROS amounts.