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Ultraviolet radiation (UVR) tends to damage key cellular machinery. Cells may adapt by developing several defence mechanisms as a response to such damage; otherwise, their destiny is cell death. Since cyanobacteria are primary biotic components and also important biomass producers, any drastic effects caused by UVR may imbalance the entire ecosystem. Cyanobacteria are exposed to UVR in their natural habitats. This exposure can cause oxidative stress which affects cellular morphology and vital processes such as cell growth and differentiation, pigmentation, photosynthesis, nitrogen metabolism, and enzyme activity, as well as alterations in the native structure of biomolecules such as proteins and DNA. The high resilience and several mitigation strategies adopted by a cyanobacterial community in the face of UV stress are attributed to the activation of several photo/dark repair mechanisms, avoidance, scavenging, screening, antioxidant systems, and the biosynthesis of UV photoprotectants, such as mycosporine-like amino acids (MAAs), scytonemin (Scy), carotenoids, and polyamines. This knowledge can be used to develop new strategies for protecting other organisms from the harmful effects of UVR. The review critically reports the latest updates on various resilience and defence mechanisms employed by cyanobacteria to withstand UV-stressed environments. In addition, recent developments in the field of the molecular biology of UV-absorbing compounds such as mycosporine-like amino acids and scytonemin and the possible role of programmed cell death, signal perception, and transduction under UVR stress are discussed.
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Cianobactérias , Raios Ultravioleta , Raios Ultravioleta/efeitos adversos , Ecossistema , Aminoácidos/metabolismo , Cianobactérias/metabolismoRESUMO
Optimal rehabilitation of asymmetric dentofacial deformity secondary to unilateral temporomandibular joint (TMJ) ankylosis is often a challenge. The purpose of this case series is to present an insight into esthetic, occlusal and functional rehabilitation of two patients with varying degree of asymmetric Class II dentofacial deformities secondary to long-standing unilateral TMJ ankylosis. The patients were treated with one-stage surgical protocol employing simultaneous dual distraction technique along with interpositional arthroplasty. Dual distraction technique entailed the simultaneous use of two distractors which allowed for proper control of proximal condylar segment during the course of distraction and lowering the risk of ankylosis recurrence. Thereafter, comprehensive fixed orthodontic mechanotherapy involving the use of temporary anchorage devices was instituted to align and level the compensated dentition. Post-treatment records showed significant improvements in skeletal disharmony and functional stability with good functional occlusion. At the three-year follow-up, the morphological and functionally acceptable results were reasonably well-maintained, with no signs of relapse. Through the two cases reported here, we would like to highlight that one-stage concurrent arthroplasty and dual distraction technique is a safe, stable, and reliable approach for surgical and functional rehabilitation of an adult asymmetric dentofacial deformity secondary to unilateral TMJ ankylosis. Meticulously executed comprehensive orthodontic manipulations involving use of acrylic bite-blocks, elastic traction, and temporary skeletal anchorage device play a crucial role in enhancing the final occlusal outcomes.
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Anquilose , Deformidades Dentofaciais , Ortodontia , Adulto , Humanos , Seguimentos , Anquilose/etiologia , Anquilose/cirurgia , Articulação Temporomandibular/cirurgiaRESUMO
In 2019-2020, the novel "severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)" had emerged as the biggest challenge for humanity, causing "coronavirus disease 19 (COVID-19)". Scientists around the world have been putting continuous efforts to unfold potential inhibitors of SARS-CoV-2. We have performed computational studies that help us to identify cyanobacterial photoprotective compounds as potential inhibitors against SARS-CoV-2 druggable target human angiotensin-converting enzyme (ACE2), which plays a vital role in the attachment and entry of the virus into the cell. Blocking the receptor-binding domain of ACE2 can prevent the access of the virus into the compartment. A molecular docking study was performed between photoprotective compounds mycosporine-like amino acids, scytonemins and ACE2 protein using AutoDock tools. Among sixteen molecularly docked metabolites, seven compounds were selected with binding energy < 6.8 kcal/mol. Afterwards, drug-likeness and toxicity of the top candidate were predicted using Swiss ADME and Pro Tox-II online servers. All top hits show desirable drug-likeness properties, but toxicity pattern analysis discloses the toxic effect of scytonemin and its derivatives, resulting in the elimination from the screening pipeline. Further molecular interaction study of the rest two ligands, mycosporine-glycine-valine and shinorine with ACE2 was performed using PyMol, Biovia Discovery studio and LigPlot+. Lastly biological activity of both the ligands was predicted by using the PASS online server. Combining the docking score and other studied properties, we believe that mycosporine-glycine-valine and shinorine have potential to be potent inhibitors of ACE2 and can be explored further to use against COVID-19.
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Environmental stresses negatively affect plant development and significantly influence global agricultural productivity. The growth suppression due to soil salinity involves osmotic stress, which is accompanied by ion toxicity, nutritional imbalance, and oxidative stress. The amelioration of salinity stress is one of the fundamental goals to be achieved to ensure food security and better meet the issues related to global hunger. The application of exogenous chemicals is the imperative and efficient choice to alleviate stress in the agricultural field. Among them, hydrogen sulfide (H2 S, a gasotransmitter) is known for its efficient role in stress mitigation, including salinity stress, along with other biological features related to growth and development in plants. H2 S plays a role in improving photosynthesis and ROS homeostasis, and interacts with other signaling components in a cascade fashion. The current review gives a comprehensive view of the participation of H2 S in salinity stress alleviation in plants. Further, its crosstalk with other stress ameliorating signaling component or supplement (e.g., NO, H2 O2 , melatonin) is also covered and discussed. Finally, we discuss the possible prospects to meet with success in agricultural fields.
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Sulfeto de Hidrogênio , Plantas , Salinidade , Estresse Salino , Estresse FisiológicoRESUMO
BACKGROUND AND AIMS: Nitrogen (N) levels vary between ecosystems, while the form of available N has a substantial impact on growth, development and perception of stress. Plants have the capacity to assimilate N in the form of either nitrate (NO3-) or ammonium (NH4+). Recent studies revealed that NO3- nutrition increases nitric oxide (NO) levels under hypoxia. When oxygen availability changes, plants need to generate energy to protect themselves against hypoxia-induced damage. As the effects of NO3- or NH4+ nutrition on energy production remain unresolved, this study was conducted to investigate the role of N source on group VII transcription factors, fermentative genes, energy metabolism and respiration under normoxic and hypoxic conditions. METHODS: We used Arabidopsis plants grown on Hoagland medium with either NO3- or NH4+ as a source of N and exposed to 0.8 % oxygen environment. In both roots and seedlings, we investigated the phytoglobin-nitric oxide cycle and the pathways of fermentation and respiration; furthermore, NO levels were tested using a combination of techniques including diaminofluorescein fluorescence, the gas phase Griess reagent assay, respiration by using an oxygen sensor and gene expression analysis by real-time quantitative reverse transcription-PCR methods. KEY RESULTS: Under NO3- nutrition, hypoxic stress leads to increases in nitrate reductase activity, NO production, class 1 phytoglobin transcript abundance and metphytoglobin reductase activity. In contrast, none of these processes responded to hypoxia under NH4+ nutrition. Under NO3- nutrition, a decreased total respiratory rate and increased alternative oxidase capacity and expression were observed during hypoxia. Data correlated with decreased reactive oxygen species and lipid peroxidation levels. Moreover, increased fermentation and NAD+ recycling as well as increased ATP production concomitant with the increased expression of transcription factor genes HRE1, HRE2, RAP2.2 and RAP2.12 were observed during hypoxia under NO3- nutrition. CONCLUSIONS: The results of this study collectively indicate that nitrate nutrition influences multiple factors in order to increase energy efficiency under hypoxia.
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Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Metabolismo Energético , Nitratos/metabolismo , Fatores de Transcrição/genética , Anaerobiose , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Nutrientes/metabolismo , Oxigênio/análise , Fatores de Transcrição/metabolismoRESUMO
PURPOSE: Temporomandibular joint (TMJ) ankylosis, not only results in joint hypomobility, but also causes considerable facial deformity. Its unilateral variant can cause facial asymmetry, leading to major psychosocial effects on the individual. PATIENTS AND METHODS: We present the cases of 7 patients with unilateral TMJ ankylosis and facial asymmetry of various grades who have been treated using gap arthroplasty and simultaneous dual distraction. Considerable debate has surrounded the sequencing of TMJ release and distraction osteogenesis; however, the simultaneous approach has recently become popular. The use of a single distractor simultaneously with TMJ release has been widely reported. However, one disadvantage with this technique is that the proximal condylar segment remains unstable. Dual distraction is a newer technique which we have proposed as a single-stage approach for the correction of TMJ ankylosis and facial asymmetry and to address the problems resulting from the use of a single distractor. RESULTS: After treatment, all the patients showed a mouth opening ranging from 35 to 50 mm and satisfactory facial symmetry. CONCLUSIONS: Dual distraction is a promising technique in the correction of facial asymmetry. However, further studies with adequate statistical analysis and larger sample size are required.
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Anquilose , Assimetria Facial , Osteogênese por Distração , Transtornos da Articulação Temporomandibular , Anquilose/complicações , Anquilose/cirurgia , Artroplastia , Humanos , Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/cirurgiaRESUMO
Submergence, whether partial or complete, imparts some serious consequences on plants grown in flood prone ecosystems. Some plants can endure these conditions by embracing various survival strategies, including morphological adaptations and physiological adjustments. This review summarizes recent progress made in understanding of the stress and the acclimation responses of plants under waterlogged or submerged conditions. Waterlogging and submergence are often associated with hypoxia development, which may trigger various morphological traits and cellular acclimation responses. Ethylene, abscisic acid, gibberellic acid and other hormones play a crucial role in the survival process which is controlled genetically. Effects at the cellular level, including ATP management, starch metabolism, elemental toxicity, role of transporters and redox status have been explained. Transcriptional and hormonal interplay during this stress may provide some key aspects in understanding waterlogging and submergence tolerance. The level and degree of tolerance may vary depending on species or climatic variations which need to be studied for a proper understanding of waterlogging stress at the global level. The exploration of regulatory pathways and interplay in model organisms such as Arabidopsis and rice would provide valuable resources for improvement of economically and agriculturally important plants in waterlogging affected areas.
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Adaptação Fisiológica , Fenômenos Fisiológicos Vegetais , Plantas/anatomia & histologia , Água/fisiologia , Inundações , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/fisiologia , Estresse Fisiológico , Transcrição GênicaRESUMO
The AP2/ERFs are one of the most important family of transcription factors which regulate multiple responses like stress, metabolism and development in plants. We isolated PsAP2 a novel AP2/ERF from Papaver somniferum which was highly upregulated in response to wounding followed by ethylene, methyl jasmonate and ABA treatment. PsAP2 showed specific binding with both DRE and GCC box elements and it was able to transactivate the reporter genes in yeast. PsAP2 overexpressing transgenic tobacco plants exhibited enhanced tolerance towards both abiotic and biotic stresses . Real time transcript expression analysis showed constitutive upregulation of tobacco Alternative oxidase1a and Myo-inositol-1-phosphate synthase in PsAP2 overexpressing tobacco plants. Further, PsAP2 showed interaction with NtAOX1a promoter in vitro, it also specifically activated the NtAOX1a promoter in yeast and tobacco BY2 cells. The silencing of PsAP2 using VIGS lead to significant reduction in the AOX1 level in P. somniferum. Taken together PsAP2 can directly bind and transcriptionally activate NtAOX1a and its overexpression in tobacco imparted increased tolerance towards both abiotic and biotic stress.
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Papaver/fisiologia , Proteínas de Plantas/fisiologia , Estresse Fisiológico/fisiologia , Fatores de Transcrição/fisiologia , Sequência de Aminoácidos , Sequência de Bases , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Inativação Gênica/fisiologia , Dados de Sequência Molecular , Papaver/genética , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Estresse Fisiológico/genética , Nicotiana/genética , Nicotiana/fisiologia , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Saponins are mainly amphipathic glycosides that posses many biological activities and confer potential health benefits to humans. Inspite of its medicinal attributes most of the triterpenes and enzymes involved in the saponin biosynthesis remains uncharacterized at the molecular level. Since the major steroidal components are present in the roots of A. racemosus our study is focussed on the comparative denovo transcriptome analysis of root versus leaf tissue and identifying some root specific transcripts involved in saponin biosynthesis using high-throughput next generation transcriptome sequencing. RESULTS: After sequencing, de novo assembly and quantitative assessment, 126861 unigenes were finally generated with an average length of 1200 bp. Then functional annotation and GO enrichment analysis was performed by aligning all-unigenes with public protein databases including NR, SwissProt, and KEGG. Differentially expressed genes in root were initially identified using the RPKM method using digital subtraction between root and leaf. Twenty seven putative secondary metabolite related transcripts were experimentally validated for their expression in root or leaf tissue using q-RT PCR analysis. Most of the above selected transcripts showed preferential expression in root as compared to leaf supporting the digitally subtracted result obtained. The methyl jasmonate application induces the secondary metabolite related gene transcripts leading to their increased accumulation in plants. Therefore, the identified transcripts related to saponin biosynthesis were further analyzed for their induced expression after 3, 5 and 12 hours of exogenous application of Methyl Jasmonate in tissue specific manner. CONCLUSIONS: In this study, we have identified a large set of cDNA unigenes from A. racemosus leaf and root tissue. This is the first transcriptome sequencing of this non-model species using Illumina, a next generation sequencing technology. The present study has also identified number of root specific transcripts showing homology with saponin biosynthetic pathway. An integrated pathway of identified saponin biosynthesis transcripts their tissue specific expression and induced accumulation after methyl jasmonate treatment was discussed.
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Genes de Plantas , Magnoliopsida/genética , Magnoliopsida/metabolismo , Folhas de Planta/genética , Raízes de Plantas/genética , Sapogeninas/metabolismo , Transcriptoma , Acetatos/farmacologia , Biologia Computacional , Ciclopentanos/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Oxilipinas/farmacologia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Reprodutibilidade dos TestesRESUMO
Plants posses a complex co-regulatory network which helps them to elicit a response under diverse adverse conditions. We used an in silico approach to identify the genes with both DRE and ABRE motifs in their promoter regions in Arabidopsis thaliana. Our results showed that Arabidopsis contains a set of 2,052 genes with ABRE and DRE motifs in their promoter regions. Approximately 72% or more of the total predicted 2,052 genes had a gap distance of less than 400 bp between DRE and ABRE motifs. For positional orientation of the DRE and ABRE motifs, we found that the DR form (one in direct and the other one in reverse orientation) was more prevalent than other forms. These predicted 2,052 genes include 155 transcription factors. Using microarray data from The Arabidopsis Information Resource (TAIR) database, we present 44 transcription factors out of 155 which are upregulated by more than twofold in response to osmotic stress and ABA treatment. Fifty-one transcripts from the one predicted above were validated using semiquantitative expression analysis to support the microarray data in TAIR. Taken together, we report a set of genes containing both DRE and ABRE motifs in their promoter regions in A. thaliana, which can be useful to understand the role of ABA under osmotic stress condition.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regiões Promotoras Genéticas/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologiaRESUMO
Crocus sativus is a valuable plant due to the presence of apocarotenoids in its stigma. Considerable work has been done in the past to understand the apocarotenoid biosynthetic pathway in saffron. However, the reports on understanding the regulation of flowering at the post-transcriptional level are meagre. The study aimed to discover the candidate miRNAs, target genes, transcription factors (TFs), and apocarotenoid biosynthetic pathway genes associated with the regulation and transition of flowering in C. sativus. In the present investigation, miRNA profiling was performed in flowering and non-flowering corms of saffron, along with expression analysis of apocarotenoid genes and transcription factors involved in the synthesis of secondary metabolites. Significant modulation in the expression of miR156, miR159, miR166, miR172, miR395, miR396, miR399, and miR408 gene families was observed. We obtained 36 known miRNAs (26 in flowering and 10 in non-flowering) and 64 novel miRNAs (40 in flowering and 24 in non-flowering) unique to specific tissues in our analysis. TFs, including CsMADS and CsMYb, showed significant modulation in expression in flowering tissue, followed by CsHB. Additionally, the miRNAs were predicted to be involved in carbohydrate metabolism, phytohormone signalling, regulation of flower development, and response to stress, cold, and defence. The comprehensive study has enhanced our understanding of the regulatory machinery comprising factors like phytohormones, abiotic stress, apocarotenoid genes, transcription factors, and miRNAs responsible for the synthesis of apocarotenoids and developmental processes during and after flowering.
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Crocus , Flores , Regulação da Expressão Gênica de Plantas , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Crocus/genética , Perfilação da Expressão Gênica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: Tibial eminence fracture is an intra-articular fracture of bony attachment of ACL. The displaced fragment could hinder the mobility of the knee and may lead joint instabilty; therefore, requires fixation. Arthroscopic suture and screw fixation are the widely used surgical modalities for eminence fractures of the tibia. Past studies have not yet depicted the superiority of one method over the other. Through this cohort study, comparison of the clinical and functional outcomes of these two surgical methods was done. METHODS: A prospective, randomized, interventional study was conducted from December 2019 to January 2022 for comparing the clinical outcome of arthroscopic pull through suture fixation and arthroscopic antegrade cancellous screw fixation in skeletally mature individuals. Ninety patients (45 in each group) were randomly assigned and treated with the above two methods. A comprehensive clinical analysis was done after nine months of surgery for assessment of functional outcome, ligament laxity, range of motion, and complications if any. RESULTS: 65.55% of anterior tibial eminence fractures were caused by road traffic accidents followed by sports injuries (28.88%). The postoperative mean subjective IKDC score in the suture group was 91.36 and for the screw fixation group was 85.71 (p = 0.001). After nine months of surgery, the mean LKS was 91.96 in patients treated with suture fixation and 86.00 in patients treated with screw fixation (p = 0.001). Pivot shift grading was grade 3 in one patient of the suture group and in three patients of the screw group (p = 0.319). Seven patients who had screw fixation required re-surgery for removal of the implant; however, no such complication was seen in the suture fixation group. CONCLUSION: Arthroscopic pull-through suture fixation of tibial avulsion of ACL in skeletally mature patients seems to be a superior intervention over arthroscopic screw fixation with the benefits of better clinical and functional outcomes and decreased chances of re-surgery.
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Introduction: Pediatric sudden sensorineural hearing loss (SSNHL) is a rare otological emergency. With the emergence of the Coronavirus 19 pandemic, alcohol-based hand sanitizers are among the essential household items. Many hand sanitizers are frequently coupled with scents that young children may find pleasant. Case Report: A 5-year-old girl presented to our clinic with hearing loss after the consumption of alcohol-based hand sanitizer. A pure tone audiogram showed bilateral SSNHL. The child was prescribed systemic corticosteroids resulted in a slight improvement in hearing thresholds. The child was followed up at 6 and 18 months showing no further improvement in hearing thresholds. Conclusion: Although various infective, vascular, and immune responses have been proposed, alcohol-based hand sanitizer consumption has not been reported to present with SSNHL to the best of our knowledge. In the current scenario of the Coronavirus pandemic, otorhinolaryngologists must keep in mind that SSNHL may occur as a result of hazardous alcohol-based hand disinfectant consumption.
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Anterior maxillary distraction osteogenesis (AMDO) is often used for the correction of maxillary retrognathia in select cleft lip and palate cases. The restoration of alveolar arch continuity is desirable before the initiation of AMDO in these cleft maxillary deformities; however, AMDO is technically difficult in a patient with coexisting alveolar cleft where there is a discontinuity of the defect that presents a challenge in terms of adequate vector control of the movement of the anterior segment and the potential risk of tipping of teeth, which already have compromised anchorage/bone support on the cleft side. The treatment becomes more challenging when ongoing management is compounded by failed previous alveolar cleft grafting procedures, along with the patient's reluctance to undergo further grafting of alveolar clefts. This technical note demonstrates a novel application of the modification of the Hyrax screw where an initially fully opened Hyrax screw was utilised as an interim assembly for accomplishing the single-step closure of a small alveolar cleft before the commencement of anterior maxillary distraction osteogenesis. This technique may prove to be feasible for patients presenting with alveolar cleft defects of smaller widths of up to 5 mm and relatively well-aligned upper arches.
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Fenda Labial , Fissura Palatina , Osteogênese por Distração , Humanos , Fissura Palatina/cirurgia , Fenda Labial/cirurgia , Osteogênese por Distração/métodos , Maxila/cirurgia , Maxila/anormalidades , Parafusos ÓsseosRESUMO
BACKGROUND: Magnesium sulphate (MgSO4) is conventionally used in the treatment of eclampsia, refractive arrhythmias, asthma, etc. In our study, we aimed to study the analgesic effects of MgSO4 as an adjuvant to fentanyl and reduce the intraoperative opioid requirement to decrease their adverse effects. METHODS: A total of 122 patients scheduled for hysteroscopy were randomly divided into two groups. Patients in the magnesium group (group A) received intravenous MgSO4 50 mg/kg in 100 ml of isotonic saline over 15 minutes before anaesthesia induction and then 15 mg/kg per hour by continuous intravenous infusion. Patients in the control group (group B) received an equal volume of isotonic saline as a placebo. All the patients were induced with fentanyl and propofol. Perioperative haemodynamic monitoring and postoperative assessment of pain were done. RESULTS: Only 18% of the patients in group A required rescue analgesics as compared to 39.3% of patients in group B. The patients receiving MgSO4 displayed lower verbal numeric rating scale scores in the postoperative period. In addition, the intraoperative requirement of fentanyl (101 (21.33) vs. 144 (28.4) µg, mean (SD)) and propofol (121 (13.3) vs. 140 (16.5) mg, mean (SD)) was significantly lower in group A as compared to that in group B. CONCLUSION: MgSO4, when administered as an adjuvant to opioids, provided effective postoperative analgesia thereby reducing the need for rescue analgesics. It also decreases intraoperative fentanyl consumption and its dose-related side effects.
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A biofilm is an aggregation of surface-associated microbial cells that is confined in an extracellular polymeric substance (EPS) matrix. Infections caused by microbes that form biofilms are linked to a variety of animals, including insects and humans. Antibiotics and other antimicrobials can be used to remove or eradicate biofilms in order to treat infections. However, due to biofilm resistance to antibiotics and antimicrobials, clinical observations and experimental research clearly demonstrates that antibiotic and antimicrobial therapies alone are frequently insufficient to completely eradicate biofilm infections. Therefore, it becomes crucial and urgent for clinicians to properly treat biofilm infections with currently available antimicrobials and analyze the results. Numerous biofilm-fighting strategies have been developed as a result of advancements in nanoparticle synthesis with an emphasis on metal oxide np. This review focuses on several therapeutic strategies that are currently being used and also those that could be developed in the future. These strategies aim to address important structural and functional aspects of microbial biofilms as well as biofilms' mechanisms for drug resistance, including the EPS matrix, quorum sensing (QS), and dormant cell targeting. The NPs have demonstrated significant efficacy against bacterial biofilms in a variety of bacterial species. To overcome resistance, treatments such as nanotechnology, quorum sensing, and photodynamic therapy could be used.
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Plants are one of the vital sources of secondary metabolites. These secondary metabolites have diverse roles in human welfare, including therapeutic implication. Nevertheless, secondary metabolite yields obtained through the exploitation of natural plant populations is insufficient to meet the commercial demand due to their accumulation in low volumes. Besides, in-planta synthesis of these important metabolites is directly linked with the age and growing conditions of the plant. Such limitations have paved the way for the exploration of alternative production methodologies. Hairy root cultures, induced after the interaction of plants with Rhizobium rhizogenes (Agrobacterium rhizogenes), are a practical solution for producing valuable secondary metabolite at low cost and without the influence of seasonal, geographic or climatic variations. Hairy root cultures also offer the opportunity to get combined with other yield enhancements strategies (precursor feeding, elicitation and metabolic engineering) to further stimulate and/or enhance their production potential. Applications of metabolic engineering in exploiting hairy root cultures attracted the interest of several research groups as a means of yield enhancement. Currently, several engineering approaches like overexpression and silencing of pathway genes, and transcription factor overexpression are used to boost metabolite production, along with the contextual success of genome editing. This review attempts to cover metabolic engineering in hairy roots for the production of secondary metabolites, with a primary emphasis on alkaloids, and discusses prospects for taking this research forward to meet desired production demands.
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Alcaloides , Engenharia Metabólica , Humanos , Plantas Geneticamente Modificadas/genética , Agrobacterium/genética , Raízes de Plantas/metabolismoRESUMO
Cyanobacteria have been recognized as a rich source of bioactive metabolites with potential biotechnological applications in the pharmacological industry. The chemically diverse natural compounds or their analogues cause cytotoxicity. They may kill various cancer cells by inducing apoptosis or changing the activation of cell signaling, particularly involving the protein kinase-C family of enzymes, mitochondrial dysfunctions, and oxidative damage. B cell lymphoma 2 (Bcl-2) is an essential component of apoptosis and is an antiapoptotic molecule. The key apoptotic regulators associated with cancer are members of the Bcl-2 protein family, the key member of which is Bcl-2. The Bcl-2 protein is a promising target for the emergence of new anti-tumor therapies because of its critical role in controlling apoptosis. This review explores the significance of Bcl-2 in the onset of cancer; it may be used as a target for developing high-quality drug therapies to treat various tumors. In addition, a number of computational techniques were used to identify novel hit compounds that may act as inhibitors of the apoptotic protein Bcl-2, including virtual screening, toxicity prediction, and drug-likeness analysis. Twenty-three compounds were assessed as potential hits against Bcl-2, and these compounds were subjected to ADMET property prediction. Dendroamide A and Welwitindolinone A appear to be the most stable and effective drugs against Bcl-2 out of all those evaluated. This article gives an overview of the bioactive compounds produced by cyanobacteria that have anticancer properties and may be exploited to create novel anticancer medications in the future.
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Antineoplásicos , Cianobactérias , Neoplasias , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Proteínas Reguladoras de Apoptose/farmacologia , Neoplasias/tratamento farmacológico , Linhagem Celular TumoralRESUMO
Salinity or salt stress has deleterious effects on plant growth and development. It imposes osmotic, ionic, and secondary stresses, including oxidative stress on the plants and is responsible for the reduction of overall crop productivity and therefore challenges global food security. Plants respond to salinity, by triggering homoeostatic mechanisms that counter salt-triggered disturbances in the physiology and biochemistry of plants. This involves the activation of many signaling components such as SOS pathway, ABA pathway, and ROS and osmotic stress signaling. These biochemical responses are accompanied by transcriptional modulation of stress-responsive genes, which is mostly mediated by salt-induced transcription factor (TF) activity. Among the TFs, the multifaceted significance of WRKY proteins has been realized in many diverse avenues of plants' life including regulation of plant stress response. Therefore, in this review, we aimed to highlight the significance of salinity in a global perspective, the mechanism of salt sensing in plants, and the contribution of WRKYs in the modulation of plants' response to salinity stress. This review will be a substantial tool to investigate this problem in different perspectives, targeting WRKY and offering directions to better manage salinity stress in the field to ensure food security.