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1.
Vaccine ; 42(14): 3365-3373, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38627145

RESUMO

The head domain of the hemagglutinin of influenza viruses plays a dominant role in the antibody response due to the presence of immunodominant antigenic sites that are the main targets of host neutralizing antibodies. For the H1 hemagglutinin, five major antigenic sites defined as Sa, Sb, Ca1, Ca2, and Cb have been described. Although previous studies have focused on defining the hierarchy of the antigenic sites of the hemagglutinin in different human cohorts, it is still unclear if the immunodominance profile of the antigenic sites might change with the antibody levels of individuals or if other demographic factors (such as exposure history, sex, or age) could also influence the importance of the antigenic sites. The major antigenic sites of influenza viruses hemagglutinins are responsible for eliciting most of the hemagglutination inhibition antibodies in the host. To determine the antibody prevalence towards each major antigenic site, we evaluated the hemagglutination inhibition against a panel of mutant H1 viruses, each one lacking one of the "classic" antigenic sites. Our results showed that the individuals from the Stop Flu NYU cohort had an immunodominant response towards the sites Sb and Ca2 of H1 hemagglutinin. A simple logistic regression analysis of the immunodominance profiles and the hemagglutination inhibition titers displayed by each donor revealed that individuals with high hemagglutination inhibition titers against the wild-type influenza virus exhibited higher probabilities of displaying an immunodominance profile dominated by Sb, followed by Ca2 (Sb > Ca2 profile), while individuals with low hemagglutination inhibition titers presented a higher chance of displaying an immunodominance profile in which Sb and Ca2 presented the same level of immunodominance (Sb = Ca2 profile). Finally, while age exhibited an influence on the immunodominance of the antigenic sites, biological sex was not related to displaying a specific immunodominance profile.


Assuntos
Anticorpos Antivirais , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Epitopos Imunodominantes , Influenza Humana , Humanos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Feminino , Masculino , Adulto , Epitopos Imunodominantes/imunologia , Pessoa de Meia-Idade , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Adulto Jovem , Fatores Etários , Fatores Sexuais , Adolescente , Estudos de Coortes , Idoso , Antígenos Virais/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue
2.
J World Fed Orthod ; 12(5): 197-206, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37558596

RESUMO

BACKGROUND: The purpose of this study was to compare the success rate of infrazygomatic mini-implants between adolescents and young adults. METHODS: A total of 60 subjects of different age groups ie, (group I [adolescents]: 12-18 years, mean age: 14.9 ± 2.9 years; group II [young adults]: 19-25 years, mean age = 21.9 ± 3.1 years) were assessed in the study. En-masse retraction of maxillary anterior teeth was carried out with extraction of upper first premolars with infrazygomatic crest (IZC) mini-implants as anchorage units. Clinical parameters such as success rate, soft tissue thickness, maximum insertion torque, maximum removal torque, pain response, soft tissue response, and cone-beam computed tomography parameters such as embedded angulation, penetration depth, thickness of bone on buccal and palatal aspect of mini-implant, and peri-implant bone density were evaluated. RESULTS: The success rate of IZC mini-implants in adolescents was found to be 96.6% and 98.3% in young adults respectively. There was no significant difference in success rate between the two groups. Intergroup comparison showed a significant difference (P < 0.05) in terms of maximum insertion torque, maximum removal torque, soft tissue thickness, cortical bone thickness, and peri-implant bone density values. Comparison between right and left side revealed a significant difference (P < 0.05) with regards to soft tissue response, soft tissue thickness, total bone thickness, cortical bone thickness, and peri-implant bone density. CONCLUSIONS: There was no significant difference in the success rate of IZC mini-implants between adolescents and young adults. Thus, the use of IZC mini-implants can be recommended in adolescents for successful orthodontic treatment.


Assuntos
Implantes Dentários , Humanos , Adolescente , Adulto Jovem , Criança , Adulto , Dente Pré-Molar/cirurgia , Estudos Prospectivos , Palato , Tomografia Computadorizada de Feixe Cônico
3.
Acta Diabetol ; 60(11): 1481-1490, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37380728

RESUMO

AIMS: To examine the efficacy and safety of dapagliflozin in the treatment of hyperglycemia in cardiac surgery patients with type 2 diabetes (T2D). METHODS: Cardiac surgery patients with T2D (n = 250) were randomly assigned (1:1) to receive dapagliflozin plus basal-bolus insulin (DAPA group) or basal-bolus insulin alone (INSULIN group) in the early postoperative period. The primary outcome was mean difference in daily blood glucose (BG) concentrations between groups. The major safety outcomes were the occurrence of severe ketonemia/diabetic ketoacidosis (DKA) and hypoglycemia. All analyses were performed according to the intention-to-treat principle. RESULTS: The median age of the patients was 61 years (range, 55-61), and 219 (87.6%) were men. Overall, the randomization blood glucose was 165 mg/dL (SD, 37) and glycated hemoglobin was 7.7% (SD, 1.4). There were no differences in mean daily BG concentrations (149 vs. 150 mg/dL), mean percentage of readings within target BG of 70-180 mg/dL (82.7% vs. 82.5%), total daily insulin dose (mean, 39 vs. 40 units/day), number of daily insulin injections (median, 3.9 vs. 4), length of hospital stay (median, 10 vs. 10 days), or hospital complications (21.6% vs. 24.8%) between the DAPA and INSULIN groups. The mean plasma ketone levels were significantly higher in the DAPA group than in the INSULIN group at day 3 (0.71 vs. 0.30 mmol/L) and day 5 (0.42 vs. 0.19 mmol/L) of randomization. Six patients in the DAPA group developed severe ketonemia, but no patient developed DKA. There were no differences in the proportion of patients with BG < 70 mg/dL (9.6% vs. 7.2%) between the two groups. CONCLUSION: Dapagliflozin complementary to basal-bolus insulin does not improve glycemia further over and above the basal-bolus insulin alone in hospitalized cardiac surgery patients. Dapagliflozin significantly increases plasma ketones levels. Safety of dapagliflozin in hospitalized patients needs further investigation. Trial registration ClinicalTrials.gov NCT05457933.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Diabetes Mellitus Tipo 2 , Cetoacidose Diabética , Hiperglicemia , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/cirurgia , Hipoglicemiantes/uso terapêutico , Glicemia , Pacientes Internados , Resultado do Tratamento , Insulina/uso terapêutico , Hiperglicemia/tratamento farmacológico , Hiperglicemia/etiologia , Cetoacidose Diabética/tratamento farmacológico , Hospitais
4.
Mini Rev Med Chem ; 23(19): 1871-1892, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37157201

RESUMO

Hepatocellular carcinoma (HCC) is rapidly spreading around the world with a high mortality rate. In the low- and middle-income nations most impacted by HCV and HBV infections, HCC places a significant strain on the healthcare system and leaches productive capability. An extensive study on HCC to create novel therapeutic approaches was motivated by the lack of adequate preventive or curative therapy methods. Several medications have been put forward and some drug molecules are under investigation by the Food and Drug Administration (FDA) for the treatment of HCC. However, these therapeutic choices fall short of the ideal due to toxicity and the rapid rise in drug resistance which decreases the efficacy of these therapeutics and leads to the severity of hepatocellular carcinoma. Therefore, concerning these problems, there is a critical need for novel systemic combination therapies as well as novel molecular entities that target various signalling pathways, reducing the likelihood that cancer cells may develop treatment resistance. In this review, we discuss the conclusions of several studies suggesting that the N-heterocyclic ring system is a key structural component of many synthetic drugs with a diverse range of biological activities. Following nuclei, such as pyridazine, pyridine, and pyrimidines, along with benzimidazole, indole, acridine, oxadiazole, imidazole, isoxazole, pyrazole, quinolines, and quinazolines, have been included to provide a general overview of the link between structure and activity between heterocyclics and their derivatives against hepatocellular carcinoma. A comprehensive investigation of the structure-activity relationship between the series may be done by the direct comparison of anticancer activities with the reference.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Relação Estrutura-Atividade , Pirimidinas/uso terapêutico
5.
Curr Med Chem ; 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37221681

RESUMO

The uncontrolled growth and spread of aberrant cells characterize the group of disorders known as cancer. According to GLOBOCAN 2022 analysis of cancer patients in either developed countries or developing countries the main concern cancers are breast cancer, lung cancer, and liver cancer which may rise eventually. Natural substances with dietary origins have gained interest for their low toxicity, anti-inflammatory, and antioxidant effects. The evaluation of dietary natural products as chemopreventive and therapeutic agents, the identification, characterization, and synthesis of their active components, as well as the enhancement of their delivery and bioavailability, have all received significant attention. Thus, the treatment strategy for concerning cancers must be significantly evaluated and may include the use of phytochemicals in daily lifestyle. In the present perspective, we discussed one of the potent phytochemicals, that has been used over the past few decades known as curcumin as a panacea drug of the "Cure-all" therapy concept. In our review firstly we included exhausted data from in-vivo and in-vitro studies on breast cancer, lung cancer, and liver cancer which act through various cancer-targeting pathways at the molecular level. Now, the second is the active constituent of turmeric known as curcumin and its derivatives are enlisted with their targeted protein in the molecular docking studies, which help the researchers design and synthesize new curcumin derivatives with respective implicated molecular and cellular activity. However, curcumin and its substituted derivatives still need to be investigated with unknown targeting mechanism studies in depth.

6.
Diabet Med ; 40(1): e15002, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36354383

RESUMO

AIMS: To compare the efficacy and safety of degludec U100 versus glargine U300 for the early postoperative management of patients with type 2 diabetes mellitus (T2D) undergoing coronary artery bypass graft (CABG) surgery. METHODS: A total of 239 patients were randomly assigned (1:1) to receive a basal-bolus regimen in the early postoperative period using degludec U100 (n = 122) or glargine U300 (n = 117) as basal and glulisine before meals. The primary outcome was mean differences between groups in their daily BG concentrations. The major safety outcome was the occurrence of hypoglycemia. RESULTS: There were no differences in mean daily BG concentrations (157 vs. 162 mg/dl), mean percentage of readings within target BG of 70-180 mg/dl (74% vs. 73%), daily basal insulin dose (19 vs. 21 units/day), length of stay (median [IQR]: 9 vs. 9 days), or hospital complications (21.3% vs. 21.4%) between treatment groups. There were no differences in the proportion of patients with BG <70 mg/dl (15.6% vs. 23.1%) or <54 mg/dl (1.6% vs. 4.3%) between degludec-100 and glargine-300 groups. CONCLUSIONS: Treatment with degludec U100 is as effective and safe as glargine U300 for the early postoperative hospital management of patients with T2D undergoing CABG.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Insulina Glargina/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Ponte de Artéria Coronária , Período Pós-Operatório , Glicemia
7.
Viruses ; 14(5)2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35632677

RESUMO

Immunocompromised individuals are at risk of prolonged SARS-CoV-2 infection due to weaker immunity, co-morbidities, and lowered vaccine effectiveness, which may evolve highly mutated variants of SARS-CoV-2. Nonetheless, limited data are available on the immune responses elicited by SARS-CoV-2 infection, reinfections, and vaccinations with emerging variants in immunocompromised patients. We analyzed clinical samples that were opportunistically collected from eight immunocompromised individuals for mutations in SARS-CoV-2 genomes, neutralizing antibody (NAb) titers against different SARS-CoV-2 variants, and the identification of immunoreactive epitopes using a high-throughput coronavirus peptide array. The viral genome analysis revealed two SARS-CoV-2 variants (20A from a deceased patient and an Alpha variant from a recovered patient) with an eight amino-acid (aa) deletion within the N-terminal domain (NTD) of the surface glycoprotein. A higher NAb titer was present against the prototypic USA/WA1/2020 strain in vaccinated immunocompromised patients. NAb titer was absent against the Omicron variant and the cultured virus of the 20A variant with eight aa deletions in non-vaccinated patients. Our data suggest that fatal SARS-CoV-2 infections may occur in immunocompromised individuals even with high titers of NAb post-vaccination. Moreover, persistent SARS-CoV-2 infection may lead to the emergence of newer variants with additional mutations favoring the survival and fitness of the pathogen that include deletions in NAb binding sites in the SARS-CoV-2 surface glycoprotein.


Assuntos
COVID-19 , Vacinas Virais , Humanos , Hospedeiro Imunocomprometido , Glicoproteínas de Membrana , SARS-CoV-2/genética
8.
In Silico Pharmacol ; 10(1): 7, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433192

RESUMO

Piperidine and piperazine derivatives exhibit a diverse range of biological applications, including antipsychotic activity. In this study, a dataset of molecules containing piperidine, piperazine moieties that possess serotonin 5-HT2A and dopamine D2 inhibitory activity have been chosen for Pharmacophore modeling, Quantitative Structure-Activity (3D-QSAR) Relationship, Molecular docking, and ADME studies. The pharmacophoric hypothesis was found to be AAHPRRR_1 having seven features as one H-bond acceptor (A), one hydrophobic (H), one positive ion acceptor (P), and three aromatic rings (R), with survival score = 6.465 and AUC = 0.92. Based on the best hypothesis, the ZINC-Data base was virtually screened to find out the lead molecules. 3D-QSAR model, including internal and external validation showed comparative molecular field analysis (CoMFA) against 5HT2A (q 2 = 0.552, R 2 = 0.889, and r 2 poured. = 0.653 and number of component 5) and comparative molecular similarity indices analysis (CoMSIA) (q 2 = 0.599, R 2 = 0.893, and r 2 pred. = 0.617), for D2 (CoMFA, q 2 = 0.577, R 2 = 0.863, and r 2 pred. = 0.598) (CoMSIA, q 2 = 0.532, R 2 = 0.82) all results exhibited better productivity and significant statistical reliability of the model. The docking study was carried out on the crystal structure of 5-HT2A having PDB ID; 6A93 and D2 receptor having PDB ID; 6CM4. The screened compound ZINC74289318 possess a higher docking score - 10.744 and - 11.388 than co-crystallized ligand docking score - 8.840 and - 10.06 against 5-HT2A and D2 receptor respectively. Further, ZINC74289318 was screened for all drug-likeness parameters and no showed violation of the Lipinski rule of five. Also, it was found to possess good bioavailability of 0.55 with synthetic accessibility of 4.42 which is greater than risperidone.

10.
Emerg Infect Dis ; 27(12): 3185-3188, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34708683

RESUMO

In June 2021, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases surged in Liberia. SARS-CoV-2 sequences from patients hospitalized during March-July 2021 revealed the Delta variant was in Liberia in early March and was dominant in June, irrespective of geography. Mutations and deletions suggest multiple SARS-CoV-2 Delta variant introductions.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Libéria/epidemiologia , Análise de Sequência
11.
Diabetes Metab Syndr ; 15(4): 102174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34186369

RESUMO

AIMS: To study the feasibility of diabetes education through telemedicine in patients with diabetes mellitus (DM) hospitalized for coronavirus disease 2019 (COVID-19) management. METHODS: This was a prospective study of 100 patients with DM who were admitted in a COVID isolation ward for management of COVID-19. Patients managed with multiple subcutaneous insulin injections were eligible. During teleconsultation, diabetes education including insulin injection technique was given by a diabetes educator via a phone call (audio and video) during hospitalization. They were also re-assessed after 2 weeks of discharge from the hospital via teleconsultation or in-person. RESULTS: Out of 100 patients, 72.0% had prior history of diabetes while 28.0% were newly diagnosed. The median age of our cohort was 56 years and median duration of diabetes was 7.0 years. Telemedicine as a mode of consult for diabetes education was accepted by 96.0% of patients during hospitalization. At 2 weeks' follow-up, 77.0% patients were following insulin instructions correctly and were satisfied with this mode of consultation. CONCLUSION: Diabetes education using telemedicine as a technology is feasible, acceptable, and effective in the management of most patients with DM. Telemedicine appears to be an effective way to replace routine visits in special situations.


Assuntos
COVID-19/complicações , Diabetes Mellitus/tratamento farmacológico , Hospitalização/estatística & dados numéricos , Insulina/administração & dosagem , Consulta Remota/métodos , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/transmissão , COVID-19/virologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Diabetes Mellitus/virologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
J World Fed Orthod ; 10(3): 89-97, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34112627

RESUMO

OBJECTIVE: To assess the rate of tooth movement and the periodontal tissue status over a period of 90 days with and without micro-osteoperforation (MOP). METHOD: Thirty-three adults of the 19 to 25 age group undergoing labial fixed orthodontic treatment with bilateral maxillary first premolar extraction, requiring individual canine retraction as a part of the treatment plan, were recruited for this split-mouth randomized clinical trial. While performing micro-implant-assisted canine retraction in the maxillary arch, the experimental side received three MOPs each on the mesial and distal aspects of the canine root. The amount of tooth movement was measured clinically at every 15 days interval for 90 days; the periodontal status was assessed clinically (probing depth, relative attachment level) and tomographically (canine root length, alveolar bone level) at the 1st day and 90th day of retraction. The data were subjected to appropriate statistical analyses. RESULTS: A statistically significant difference in tooth movement on the MOP side was observed in the first 45 days, amounting to 1.5 times more than that of the control side. However, during 45 to 90 days, the difference in the rate of tooth movement between the sides was not statistically significant. Changes in periodontal variables were also insignificant between the sides except for the distal alveolar bone level. CONCLUSION: An increase in the rate of tooth movement can be achieved without any periodontal adverse effects in the first 45 days of the MOP procedure. The effectiveness of the MOP procedure on the rate of tooth movement gradually declined thereafter. TRIAL REGISTRATION: CTRI/2019/07/020403.


Assuntos
Boca , Técnicas de Movimentação Dentária , Dente Pré-Molar/cirurgia , Face , Maxila/diagnóstico por imagem
13.
Fish Shellfish Immunol Rep ; 2: 100023, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36420511

RESUMO

•Argulosis, a disease caused by Argulus spp. of ectoparasites in scaly fish, is a global concern for aquaculture industry.•The resistance of the parasite to anti-parasitic drugs and the quantum of loss has been felt world-wide.•The current scenario of management and the development in vaccination are discussed herewith.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32154188

RESUMO

Outer membrane proteins (OMPs) of gram-negative bacteria play an important role in mediating antibacterial resistance, bacterial virulence and thus affect pathogenic ability of the bacteria. Over the years, prevalence of environmental antibiotic resistant organisms, their transmission to clinics and ability to transfer resistance genes, have been studied extensively. Nevertheless, how successful environmental bacteria can be in establishing as pathogenic bacteria under clinical setting, is less addressed. In the present study, we utilized an integrated approach of investigating the antibiotic resistance profile, presence of outer membrane proteins and virulence factors to understand extent of threat posed due to multidrug resistant environmental Enterobacter isolates. Also, we investigated clinical Enterobacter isolates and compared the results thereof. Results of the study showed that multidrug resistant environmental Enterobacter isolates lacked OmpC, lacked cell invasion abilities and exhibited low reactive oxygen species (ROS) production in neutrophils. In contrast, clinical isolates possessed OmpF, exhibited high invasive and adhesive property and produced higher amounts of ROS in neutrophils. These attributes indicated limited pathogenic potential of environmental Enterobacter isolates. Informations obtained from whole genome sequence of two representative bacterial isolates from environment (DL4.3) and clinical sources (EspIMS6) corroborated well with the observed results. Findings of the present study are significant as it highlights limited fitness of multidrug resistant environmental Enterobacter isolates.


Assuntos
Enterobacter , Fatores de Virulência , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter/genética , Testes de Sensibilidade Microbiana , Análise de Sequência , Fatores de Virulência/genética
16.
ACS Appl Mater Interfaces ; 11(46): 42998-43017, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31664808

RESUMO

Multidrug resistant (MDR) bacteria have emerged as a major clinical challenge. The unavailability of effective antibiotics has necessitated the use of emerging nanoparticles as alternatives. In this work, we have developed carbohydrate-coated bimetallic nanoparticles (Au-AgNP, 30-40 nm diameter) that are nontoxic toward mammalian cells yet highly effective against MDR strains as compared to their monometallic counterparts (Ag-NP, Au-NP). The Au-AgNP is much more effective against Gram-negative MDR Escherichia coli and Enterobacter cloacae when compared to most of the potent antibiotics. We demonstrate that in vivo, Au-AgNP is at least 11000 times more effective than Gentamicin in eliminating MDR Methicillin Resistant Staphylococcus aureus (MRSA) infecting mice skin wounds. Au-AgNP is able to heal and regenerate infected wounds faster and in scar-free manner. In vivo results show that this Au-AgNP is very effective antibacterial agent against MDR strains and does not produce adverse toxicity. We conclude that this bimetallic nanoparticle can be safe in complete skin regeneration in bacteria infected wounds.


Assuntos
Bactérias/crescimento & desenvolvimento , Materiais Revestidos Biocompatíveis , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Ouro , Nanopartículas Metálicas , Prata , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Prata/química , Prata/farmacologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/metabolismo , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/patologia
17.
Crit Rev Biotechnol ; 39(7): 861-883, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31362527

RESUMO

Abiotic stress imposed by many factors such as: extreme water regimes, adverse temperatures, salinity, and heavy metal contamination result in severe crop yield losses worldwide. Plants must be able to quickly respond to these stresses in order to adapt to their growing conditions and minimize metabolic losses. In this context, transporter proteins play a vital role in regulating stress response mechanisms by facilitating movement of a variety of molecules and ions across the plasma membrane in order to maintain fundamental cellular processes such as ion homeostasis, osmotic adjustment, signal transduction, and detoxification. Aquaporins play a crucial role in alleviating abiotic stress by transporting water and other small molecules to maintain cellular homeostasis. Similarly, other transporter families such as CDF, ZIP, ABC, NHX, HKT, SWEETs, TMTs, and ion channels also contribute to abiotic stress tolerance. Hormones and other signaling molecules are necessary to coordinate responses across different tissues and to precisely regulate molecular trafficking. The present review highlights the current understanding of how membrane transporters orchestrate stress responses in plants. It also provides insights about the importance of these sensing and adaptive mechanisms for ensuring improved sustainable crop production during unfavorable conditions. Finally, this review discusses future prospects for the use of computational tools in constructing signaling networks to improve our understanding of the behavior of transporters under abiotic stress.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Estresse Fisiológico/fisiologia , Transporte Biológico , Secas , Metais Pesados/toxicidade , Salinidade , Temperatura
18.
Curr Comput Aided Drug Des ; 15(1): 55-66, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30324892

RESUMO

INTRODUCTION: Caspase-3 plays a leading role in apoptosis and on activation, it cleaves many protein substrates in cells and causes cell death. Since many chemotherapeutics are known to induce apoptosis in cancer cells, promotion or activation of apoptosis via targeting apoptosis regulators has been suggested as a promising strategy for anticancer drug discovery. In this paper, we studied the interaction of 1,2,4-Oxadiazoles derivatives with anticancer drug target enzymes (PDB ID 3SRC). METHODS: Molecular docking studies were performed on a series of 1,2,4-Oxadiazoles derivatives to find out molecular arrangement and spatial requirements for their binding potential for caspase-3 enzyme agonistic affinity to treat cancer. The Autodock 4.2 and GOLD 5.2 molecular modeling suites were used for the molecular docking analysis to provide information regarding important drug receptor interaction. RESULTS AND CONCLUSION: Both suites explained the spatial disposition of the drug with the active amino acid in the ligand binding domain of the enzyme. The amino acid asparagine 273 (ASN 273) of target has shown hydrogen bond interaction with the top ranked ligand.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Caspase 3/metabolismo , Ativadores de Enzimas/química , Ativadores de Enzimas/farmacologia , Simulação de Acoplamento Molecular , Humanos , Modelos Moleculares , Estrutura Molecular , Oxidiazóis/química , Oxidiazóis/farmacologia , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Relação Estrutura-Atividade
19.
Curr Comput Aided Drug Des ; 15(4): 334-366, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30394213

RESUMO

BACKGROUND: The phosphodiesterase (PDE) is a superfamily represented by four genes: PDE4A, B,C, and D which cause the hydrolysis of phosphodiester bond of cAMP to yield inactive AMP. c-AMP catalyzing enzyme is predominant in inflammatory and immunomodulatory cells. Therapy to treat Chronic Obstructive Pulmonary Disease (COPD) with the use of PDE4 inhibitors is highly envisaged. OBJECTIVE: A molecular docking experiment with large dataset of diverse scaffolds has been performed on PDE4 inhibitors to analyze the role of amino acid responsible for binding and activation of the secondary transmitters. Apart from the general docking experiment, the main focus was to discover the role of water molecules present in the ligand-binding domain. METHODS: All the compounds were docked in the PDE4B and PDE4D active cavity to produce the free binding energy scores and spatial disposition/orientation of chemical groups of inhibitors around the cavity. Under uniform condition, the experiments were carried out with and without water molecules in the LBD. The exhaustive study was carried out on the Autodock 4.2 software and explored the role of water molecules present in the binding domain. RESULTS: In presence of water molecule, Roflumilast has more binding affinity (-8.48 Kcal/mol with PDE4B enzyme and -8.91 Kcal/mol with PDE4D enzyme) and forms two hydrogen bonds with Gln443 and Glu369 and amino acid with PDE4B and PDE4D enzymes respectively. While in absence of water molecule its binding affinity has decreased (-7.3 Kcal/mol with PDE4B enzyme and -5.17 Kcal/mol with PDE4D enzyme) as well as no H-bond interactions were observed. Similar observation was made with clinically tested molecules. CONCLUSION: In protein-ligand binding interactions, appropriate selection of water molecules facilitated the ligand binding, which eventually enhances the efficiency as well as the efficacy of ligand binding.


Assuntos
Aminopiridinas/farmacologia , Benzamidas/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Inibidores da Fosfodiesterase 4/farmacologia , Aminopiridinas/química , Benzamidas/química , Sítios de Ligação/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Ciclopropanos/química , Ciclopropanos/farmacologia , Desenho de Fármacos , Humanos , Ligação de Hidrogênio/efeitos dos fármacos , Simulação de Acoplamento Molecular , Inibidores da Fosfodiesterase 4/química , Termodinâmica , Água/química
20.
Front Microbiol ; 9: 823, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780364

RESUMO

Antibacterial therapy is of paramount importance in treatment of several acute and chronic infectious diseases caused by pathogens. Over the years extensive use and misuse of antimicrobial agents has led to emergence of multidrug resistant (MDR) and extensive drug resistant (XDR) pathogens. This drastic escalation in resistant phenotype has limited the efficacy of available therapeutic options. Thus, the need of the hour is to look for alternative therapeutic approaches to mitigate healthcare concerns caused due to MDR bacterial infections. Nanoparticles have gathered much attention as potential candidates for antibacterial therapy. Equipped with advantages of, wide spectrum bactericidal activity at very low dosage, inhibitor of biofilm formation and ease of permeability, nanoparticles have been considered as leading therapeutic candidates to curtail infections resulting from MDR bacteria. However, substrate non-specificity of efflux pumps, particularly those belonging to resistance nodulation division super family, have been reported to reduce efficacy of many potent antibacterial therapeutic drugs. Previously, we had reported antibacterial activity of polysaccharide-capped silver nanoparticles (AgNPs) toward MDR bacteria. We showed that AgNPs inhibits biofilm formation and alters expression of cytoskeletal proteins FtsZ and FtsA, with minimal cytotoxicity toward mammalian cells. In the present study, we report no reduction in antibacterial efficacy of silver nanoparticles in presence of AcrAB-TolC efflux pump proteins. Antibacterial tests were performed according to CLSI macrobroth dilution method, which revealed that both silver nanoparticles exhibited bactericidal activity at very low concentrations. Further, immunoblotting results indicated that both the nanoparticles modulate the transporter AcrB protein expression. However, expression of the membrane fusion protein AcrA did show a significant increase after exposure to AgNPs. Our results indicate that both silver nanoparticles are effective in eliminating MDR Enterobacter cloacae isolates and their action was not inhibited by AcrAB-TolC efflux protein expression. As such, the above nanoparticles have strong potential to be used as effective and alternate therapeutic candidates to combat MDR gram-negative Enterobacterial pathogens.

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