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1.
Chembiochem ; 25(5): e202300721, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38226959

RESUMO

Glycated hemoglobin (GHb) found in mammals undergoes irreversible damage when exposed to external redox agents, which is much more vulnerable than its normal counterpart hemoglobin (Hb). Besides the oxygen regulation throughout the body, Hb plays a vital role in balancing immunological health and the redox cycle. Photoinduced ultra-fast electron transfer phenomena actively participate in regulation of various kind of homeostasis involved in such biomacromolecules. In the present study we have shown that a well-known mutagen Ethidium Bromide (EtBr) reduces GHb in femtosecond time scale (efficiently) upon photoexcitation after efficient recognition in the biomolecule. We have performed similar experiment by colocalizing EtBr and Iron (Fe(III)) on the micellar surface as Hb mimic in order to study the excited state EtBr dynamics to rationalize the time scale obtained from EtBr in GHb and Hb. While other experimental techniques including Dynamic Light Scattering (DLS), Zeta potential, absorbance and emission spectroscopy have been employed for the confirmation of structural perturbation of GHb compared to Hb, a detailed computational studies involving molecular docking and density functional theory (DFT) have been employed for the explanation of the experimental observations.


Assuntos
Substâncias Redutoras , Oxibato de Sódio , Animais , Hemoglobinas Glicadas , Mutagênicos , Simulação de Acoplamento Molecular , Elétrons , Compostos Férricos , Etídio , Mamíferos
2.
Cell Biochem Funct ; 41(4): 461-477, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37139830

RESUMO

The ultimate driving force, stress, promotes adaptability/evolution in proliferating organisms, transforming tumorigenic growth. Estradiol (E2) regulates both phenomena. In this study, bioinformatics-tools, site-directed-mutagenesis (human estrogen-sulfotransferase/hSULT1E1), HepG2 cells tested with N-acetyl-cysteine (NAC/thiol-inducer) or buthionine-sulfoxamine (BSO/thiol-depletory) were evaluated for hSULT1E1 (estradiol-sulphating/inactivating) functions. Reciprocal redox regulation of steroid sulfatase (STS, E2-desulfating/activating) results in the Cys-formylglycine transition by the formylglycine-forming enzyme (FGE). The enzyme sequences and structures were examined across the phylogeny. Motif/domain and the catalytic conserve sequences and protein-surface-topography (CASTp) were investigated. The E2 binding to SULT1E1 suggests that the conserved-catalytic-domain in this enzyme has critical Cysteine 83 at position. This is strongly supported by site-directed mutagenesis/HepG2-cell research. Molecular-docking and superimposition studies of E2 with the SULT1E1 of representative species and to STS reinforce this hypothesis. SULT1E1-STS are reciprocally activated in response to the cellular-redox-environment by the critical Cys of these two enzymes. The importance of E2 in organism/species proliferation and tissue tumorigenesis is highlighted.


Assuntos
Cisteína , Estrogênios , Humanos , Cisteína/metabolismo , Estradiol , Oxirredução , Mutagênese Sítio-Dirigida
3.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688775

RESUMO

This study reports a simple template-based reverse transcription-polymerase amplification assay (ST-RT-RPA) for detection of citrus tristeza virus (CTV) from crude plant extract lysed in NaOH:EDTA (1:1) without the need of tedious RNA isolation. The developed assay showed versatility in its usage as amplification can be performed at wide temperature range (14°C to 42°C) and incubation time (4 to 32 min), although the best conditions were 38°C for 30 min. The developed ST-RT-RPA assay could detect the CTV up to 10-8 dilution of crude plant extract of NaOH:EDTA and up to 0.01 fg µl-1 of RNA of CTV-infected plant tissues and 0.001 ag µl-1 of plasmid DNA containing viral insert, thus exhibiting sufficient sensitivity. ST-RT-RPA assay showed high specificity without any cross-reaction with other citrus pathogens (Indian citrus ringspot virus, citrus yellow mosaic virus, citrus yellow vein clearing virus, and Candidatus Liberibacter asiaticus) and was more sensitive in detection of CTV infection in field samples as compared to standard reverse transcription-polymerase chain reaction (RT-PCR) with later showing false negative in 7.92% of samples tested after 1 week of sampling. The developed ST-RT-RPA assay used minimally processed crude plant extract as template, tolerant to sample degradation in transit and storage, while it can be easily performed at wide temperatures and could be adopted in resource-poor setup.


Assuntos
Citrus , Transcrição Reversa , Recombinases/metabolismo , Ácido Edético , Hidróxido de Sódio , RNA , Citrus/metabolismo , Sensibilidade e Especificidade , Técnicas de Amplificação de Ácido Nucleico
4.
Inorg Chem ; 61(33): 13115-13124, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35950896

RESUMO

Toxicity induced by inorganic arsenic as AsO33- (iAsIII) is of global concern. Reliable detection of the maximum allowed contaminant level for arsenic in drinking water and in the cellular system remains a challenge for the water quality management and assessment of toxicity in the cellular milieu, respectively. A new Ir(III)-based phosphorescent molecule (AS-1; λExt = 415 nm and λEms = 600 nm, Φ = 0.3) is synthesized for the selective detection of iAsIII in an aqueous solution with a ratiometric luminescence response even in the presence of iAsV and all other common inorganic cations and anions. The relatively higher affinity of the thioimidazole ligand (HPBT) toward iAsIII led to the formation of a fluorescent molecule iAsV-HPBT (λExt = 415 nm and λEms = 466 nm, Φ = 0.28) for the reaction of iAsIII and AS-1. An improved limit of quantitation (LOQ) down to 0.2 ppb is achieved when AS-1 is used in the CTAB micellar system. Presumably, the cationic surfactants favor the localization of AS-1@CTABMicelle in mitochondria of MCF7 cells, and this is confirmed from the images of the confocal laser fluorescence scanning microscopic studies. Importantly, cell viability assay studies confirm that AS-1@CTABMicelle induces dose-dependent detoxification of iAsIII in live cells. Further, luminescence responses at 466 nm could be utilized for developing a hand-held device for the in-field application. Such a reagent that allows for ratiometric detection of iAsIII with LOQ of 2.6 nM (0.5 ppb) in water, as well as helps in visualizing its distribution in mitochondria with a detoxifying effect, is rather unique in contemporary literature.


Assuntos
Arsênio , Arsênio/toxicidade , Cetrimônio , Indicadores e Reagentes , Micelas , Mitocôndrias
5.
Gastroenterology ; 159(6): 2101-2115.e5, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32828819

RESUMO

BACKGROUND & AIMS: Countries endemic for parasitic infestations have a lower incidence of Crohn's disease (CD) than nonendemic countries, and there have been anecdotal reports of the beneficial effects of helminths in CD patients. Tuft cells in the small intestine sense and direct the immune response against eukaryotic parasites. We investigated the activities of tuft cells in patients with CD and mouse models of intestinal inflammation. METHODS: We used microscopy to quantify tuft cells in intestinal specimens from patients with ileal CD (n = 19), healthy individuals (n = 14), and TNFΔARE/+ mice, which develop Crohn's-like ileitis. We performed single-cell RNA sequencing, mass spectrometry, and microbiome profiling of intestinal tissues from wild-type and Atoh1-knockout mice, which have expansion of tuft cells, to study interactions between microbes and tuft cell populations. We assessed microbe dependence of tuft cell populations using microbiome depletion, organoids, and microbe transplant experiments. We used multiplex imaging and cytokine assays to assess alterations in inflammatory response following expansion of tuft cells with succinate administration in TNFΔARE/+ and anti-CD3E CD mouse models. RESULTS: Inflamed ileal tissues from patients and mice had reduced numbers of tuft cells, compared with healthy individuals or wild-type mice. Expansion of tuft cells was associated with increased expression of genes that regulate the tricarboxylic acid cycle, which resulted from microbe production of the metabolite succinate. Experiments in which we manipulated the intestinal microbiota of mice revealed the existence of an ATOH1-independent population of tuft cells that was sensitive to metabolites produced by microbes. Administration of succinate to mice expanded tuft cells and reduced intestinal inflammation in TNFΔARE/+ mice and anti-CD3E-treated mice, increased GATA3+ cells and type 2 cytokines (IL22, IL25, IL13), and decreased RORGT+ cells and type 17 cytokines (IL23) in a tuft cell-dependent manner. CONCLUSIONS: We found that tuft cell expansion reduced chronic intestinal inflammation in mice. Strategies to expand tuft cells might be developed for treatment of CD.


Assuntos
Células Quimiorreceptoras/imunologia , Doença de Crohn/imunologia , Microbioma Gastrointestinal/imunologia , Ileíte/imunologia , Mucosa Intestinal/imunologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Células Quimiorreceptoras/patologia , Doença de Crohn/microbiologia , Doença de Crohn/patologia , DNA Bacteriano/genética , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Humanos , Ileíte/microbiologia , Ileíte/patologia , Íleo/citologia , Íleo/imunologia , Íleo/microbiologia , Íleo/patologia , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Knockout , Fatores de Proteção , RNA Ribossômico 16S/genética , RNA-Seq , Análise de Célula Única , Ácido Succínico/imunologia , Ácido Succínico/metabolismo
6.
PLoS Biol ; 16(10): e2006687, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30346945

RESUMO

Single-cell RNA sequencing (scRNA-seq) has become a powerful tool for the systematic investigation of cellular diversity. As a number of computational tools have been developed to identify and visualize cell populations within a single scRNA-seq dataset, there is a need for methods to quantitatively and statistically define proportional shifts in cell population structures across datasets, such as expansion or shrinkage or emergence or disappearance of cell populations. Here we present sc-UniFrac, a framework to statistically quantify compositional diversity in cell populations between single-cell transcriptome landscapes. sc-UniFrac enables sensitive and robust quantification in simulated and experimental datasets in terms of both population identity and quantity. We have demonstrated the utility of sc-UniFrac in multiple applications, including assessment of biological and technical replicates, classification of tissue phenotypes and regional specification, identification and definition of altered cell infiltrates in tumorigenesis, and benchmarking batch-correction tools. sc-UniFrac provides a framework for quantifying diversity or alterations in cell populations across conditions and has broad utility for gaining insight into tissue-level perturbations at the single-cell resolution.


Assuntos
Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Análise por Conglomerados , Simulação por Computador , Bases de Dados de Ácidos Nucleicos , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Análise de Sequência de RNA/estatística & dados numéricos , Análise de Célula Única/estatística & dados numéricos , Software , Fluxo de Trabalho
7.
Nanomedicine ; 33: 102357, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33460779

RESUMO

Obesity induced chronic low-level inflammation is strongly associated with the development of insulin resistance and progression of type-2 diabetes. Systemic treatment with anti-inflammatory therapeutics requires high doses and is associated with serious adverse effects owing to generalized suppression of the immune system. Here we study localized knockdown of pro-inflammatory adipocytokines in adipose tissue macrophages (ATMs) and adipocytes using RNA interference for the treatment of insulin resistance. Chitosan nanomicelles conjugated to ATM and adipocyte targeting ligands were used to transfect short hairpin RNA (shRNA) against tumor necrosis factor-α (TNFα) and monocyte chemoattractant protein-1 (MCP-1). Subcutaneous administration of nanomicellar/pDNA polyplexes in obese-diabetic mice resulted in decreased concentration of pro-inflammatory cytokines TNFα, MCP-1, IL-6, and IL-1ß along with increased concentration of insulin-sensitizing adipokine adiponectin. Downregulation of inflammatory cytokines resulted in improved insulin sensitivity and glucose tolerance for up to six-weeks following single dose, compared to untreated obese-diabetic mice.


Assuntos
Adipocinas/metabolismo , Quitosana/química , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina/fisiologia , Insulina/metabolismo , Nanopartículas/química , Obesidade/metabolismo , Adipócitos/metabolismo , Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Animais , Materiais Biocompatíveis/química , Quitosana/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Experimental , Teste de Tolerância a Glucose , Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micelas , Células RAW 264.7 , Interferência de RNA , Fator de Necrose Tumoral alfa/metabolismo
8.
Proc Natl Acad Sci U S A ; 115(28): 7296-7301, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29941553

RESUMO

With the rise in diabetes mellitus cases worldwide and lack of patient adherence to glycemia management using injectable insulin, there is an urgent need for the development of efficient oral insulin formulations. However, the gastrointestinal tract presents a formidable barrier to oral delivery of biologics. Here we report the development of a highly effective oral insulin formulation using choline and geranate (CAGE) ionic liquid. CAGE significantly enhanced paracellular transport of insulin, while protecting it from enzymatic degradation and by interacting with the mucus layer resulting in its thinning. In vivo, insulin-CAGE demonstrated exceptional pharmacokinetic and pharmacodynamic outcome after jejunal administration in rats. Low insulin doses (3-10 U/kg) brought about a significant decrease in blood glucose levels, which were sustained for longer periods (up to 12 hours), unlike s.c. injected insulin. When 10 U/kg insulin-CAGE was orally delivered in enterically coated capsules using an oral gavage, a sustained decrease in blood glucose of up to 45% was observed. The formulation exhibited high biocompatibility and was stable for 2 months at room temperature and for at least 4 months under refrigeration. Taken together, the results indicate that CAGE is a promising oral delivery vehicle and should be further explored for oral delivery of insulin and other biologics that are currently marketed as injectables.


Assuntos
Glicemia/metabolismo , Insulina , Líquidos Iônicos , Administração Oral , Animais , Cápsulas , Colina/farmacocinética , Colina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Insulina/farmacocinética , Insulina/farmacologia , Líquidos Iônicos/farmacocinética , Líquidos Iônicos/farmacologia , Masculino , Ratos , Ratos Wistar , Terpenos/farmacocinética , Terpenos/farmacologia
9.
Drug Dev Res ; 82(1): 86-96, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32770567

RESUMO

SARS-CoV-2 or COVID-19 pandemic global outbreak created the most unstable situation of human health-economy. In the past two decades different parts of the word experienced smaller or bigger outbreak related to human coronaviruses. The spike glycoproteins of the COVID-19 (similar to SARS-CoV) attach to the angiotensin-converting enzyme (ACE2) and transit over a stabilized open state for the viral internalization to the host cells and propagate with great efficacy. Higher rate of mutability makes this virus unpredictable/less sensitive to the protein/nucleic acid based drugs. In this emergent situation, drug-induced destabilization of spike binding to RBD could be a good strategy. In the current study we demonstrated by bioinformatics (CASTp: computed atlas of surface topography of protein, PyMol: molecular visualization) and molecular docking (PatchDock and Autodock) experiments that tea flavonoids catechin products mainly epigallocatechin gallate or other like theaflavin gallate demonstrated higher atomic contact energy (ACE) value, binding energy, Ki value, ligand efficiency, surface area and more amino acid interactions than hydroxychloroquine (HCQ) during binding in the central channel of the spike protein. Moreover, out of three distinct binding sites (I, II and III) of spike core when HCQ binds only with site III (farthest from the nCoV-RBD of ACE2 contact), epigallocatechin gallate and theaflavin gallate bind all three sites. As sites I and II are in closer contact with open state location and viral-host contact area, these drugs might have significant effects. Taking into account the toxicity/side effects by chloroquine/HCQ, present drugs may be important. Our laboratory is working on tea flavonoids and other phytochemicals in the protection from toxicity, DNA/mitochondrial damage, inflammation and so on. The present data might be helpful for further analysis of flavonoids in this emergent pandemic situation.


Assuntos
Biflavonoides/metabolismo , Catequina/análogos & derivados , Biologia Computacional/métodos , Ácido Gálico/análogos & derivados , Hidroxicloroquina/metabolismo , Simulação de Acoplamento Molecular/métodos , Glicoproteína da Espícula de Coronavírus/metabolismo , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Biflavonoides/química , Sítios de Ligação/fisiologia , COVID-19/metabolismo , Catequina/química , Catequina/metabolismo , Ácido Gálico/química , Ácido Gálico/metabolismo , Humanos , Hidroxicloroquina/química , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Glicoproteína da Espícula de Coronavírus/química , Difração de Raios X/métodos
10.
J Transl Med ; 18(1): 281, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650788

RESUMO

BACKGROUND: The recent outbreak by SARS-CoV-2 has generated a chaos in global health and economy and claimed/infected a large number of lives. Closely resembling with SARS CoV, the present strain has manifested exceptionally higher degree of spreadability, virulence and stability possibly due to some unidentified mutations. The viral spike glycoprotein is very likely to interact with host Angiotensin-Converting Enzyme 2 (ACE2) and transmits its genetic materials and hijacks host machinery with extreme fidelity for self propagation. Few attempts have been made to develop a suitable vaccine or ACE2 blocker or virus-receptor inhibitor within this short period of time. METHODS: Here, attempt was taken to develop some therapeutic and vaccination strategies with a comparison of spike glycoproteins among SARS-CoV, MERS-CoV and the SARS-CoV-2. We verified their structure quality (SWISS-MODEL, Phyre2, and Pymol) topology (ProFunc), motifs (MEME Suite, GLAM2Scan), gene ontology based conserved domain (InterPro database) and screened several epitopes (SVMTrip) of SARS CoV-2 based on their energetics, IC50 and antigenicity with regard to their possible glycosylation and MHC/paratope binding (Vaxigen v2.0, HawkDock, ZDOCK Server) effects. RESULTS: We screened here few pairs of spike protein epitopic regions and selected their energetic, Inhibitory Concentration50 (IC50), MHC II reactivity and found some of those to be very good target for vaccination. A possible role of glycosylation on epitopic region showed profound effects on epitopic recognition. CONCLUSION: The present work might be helpful for the urgent development of a suitable vaccination regimen against SARS CoV-2.


Assuntos
Betacoronavirus/imunologia , Biologia Computacional/métodos , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Epitopos/imunologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Motivos de Aminoácidos , Sequência de Aminoácidos , COVID-19 , Vacinas contra COVID-19 , Sequência Conservada , Infecções por Coronavirus/prevenção & controle , Glicosilação , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Concentração Inibidora 50 , Anotação de Sequência Molecular , Pandemias , Estrutura Secundária de Proteína , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química
11.
Pharm Res ; 37(3): 34, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31942651

RESUMO

PURPOSE: Alzheimer's disease is a neurodegenerative disorder, and most common form of dementia afflicting over 35 million people worldwide. Rivastigmine is a widely used therapeutic for ameliorating clinical manifestations of Alzheimer's disease. However, current treatments require frequent dosing either orally or via transdermal patch that lead to compliance issues and administration errors risking serious adverse effects. Our objective was to develop a smart polymer based delivery system for controlled release of rivastigmine over an extended period following a single subcutaneous injection. METHODS: Rivastigmine release was optimized by tailoring critical factors including polymer concentration, polymer composition, drug concentration, solvent composition, and drug hydrophobicity (rivastigmine tartrate vs base). Optimized in vitro formulation was evaluated in vivo for safety and efficacy. RESULTS: Formulation prepared using PLGA (50:50) at 5% w/v in 95:5 benzyl benzoate: benzoic acid demonstrated desirable controlled drug release characteristics in vitro. The formulation demonstrated sustained release of rivastigmine tartrate for 7 days in vivo with promising biocompatibility and acetylcholinesterase inhibition efficacy for 14 days. CONCLUSION: The results exemplify an easily injectable controlled release formulation of rivastigmine prepared using phase-sensitive smart polymer. The optimized formulation significantly increases the dosing interval, and can potentially improve patient compliance as well as quality of life of patients living with Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/química , Portadores de Fármacos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Rivastigmina/química , Polímeros Responsivos a Estímulos/química , Inibidores da Colinesterase/administração & dosagem , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Transição de Fase , Rivastigmina/administração & dosagem , Solventes/química
12.
BMC Pregnancy Childbirth ; 20(1): 698, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198663

RESUMO

BACKGROUND: Full dilatation caesarean sections are associated with recurrent early spontaneous preterm birth and late miscarriage. The risk following first stage caesarean sections, are less well defined, but appears to be increased in late-first stage of labour. The mechanism for this increased risk of late miscarriage and early spontaneous preterm birth in these women is unknown and there are uncertainties with regards to clinical management. Current predictive models of preterm birth (based on transvaginal ultrasound and quantitative fetal fibronectin) have not been validated in these women and it is unknown whether the threshold to define a short cervix (≤25 mm) is reliable in predicting the risk of preterm birth. In addition the efficacy of standard treatments or whether benefit may be derived from prophylactic interventions such as a cervical cerclage is unknown. METHODS: There are three distinct components to the CRAFT project (CRAFT-OBS, CRAFT-RCT and CRAFT-IMG). CRAFT-OBS: Observational Study; To evaluate subsequent pregnancy risk of preterm birth in women with a prior caesarean section in established labour. This prospective study of cervical length and quantitative fetal fibronectin data will establish a predictive model of preterm birth. CRAFT-RCT: Randomised controlled trial arm; To assess treatment for short cervix in women at high risk of preterm birth following a fully dilated caesarean section. CRAFT-IMG: Imaging sub-study; To evaluate the use of MRI and transvaginal ultrasound imaging of micro and macrostructural cervical features which may predispose to preterm birth in women with a previous fully dilated caesarean section, such as scar position and niche. DISCUSSION: The CRAFT project will quantify the risk of preterm birth or late miscarriage in women with previous in-labour caesarean section, define the best management and shed light on pathological mechanisms so as to improve the care we offer to women and their babies. TRIAL REGISTRATION: CRAFT was prospectively registered on 25th November 2019 with the ISRCTN registry ( https://doi.org/10.1186/ISRCTN15068651 ).


Assuntos
Aborto Espontâneo/epidemiologia , Cerclagem Cervical/métodos , Cesárea/estatística & dados numéricos , Nascimento Prematuro/prevenção & controle , Dilatação , Feminino , Humanos , Primeira Fase do Trabalho de Parto , Trabalho de Parto , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Cell Mol Life Sci ; 76(20): 4145-4154, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31011770

RESUMO

A crucial contribution to the heterogeneity of the conformational landscape of a protein comes from the way an intermediate relates to another intermediate state in its journey from the unfolded to folded or misfolded form. Unfortunately, it is extremely hard to decode this relatedness in a quantifiable manner. Here, we developed an application of statistical cluster analyses to explore the conformational heterogeneity of a metalloenzyme, human cytosolic copper-zinc superoxide dismutase (SOD1), using the inputs from infrared spectroscopy. This study provides a quantifiable picture of how conformational information at one particular site (for example, the copper-binding pocket) is related to the information at the second site (for example, the zinc-binding pocket), and how this relatedness is transferred to the global conformational information of the protein. The distance outputs were used to quantitatively generate a network capturing the folding sub-stages of SOD1.


Assuntos
Cobre/química , Agregados Proteicos/genética , Superóxido Dismutase-1/química , Zinco/química , Sítios de Ligação , Clonagem Molecular , Análise por Conglomerados , Cobre/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Dobramento de Proteína , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Zinco/metabolismo
14.
Planta ; 250(3): 873-890, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31134340

RESUMO

MAIN CONCLUSION: Required genetic resources for the improvement of agronomic, nutritional and economic value of rice bean are available in the world collection. International cooperative effort is required to utilize and conserve them. Rice bean [Vigna umbellata (Thunb.) Ohwi and Ohashi], a lesser known pulse among the Asiatic Vigna, has long been considered as a food security crop of small and marginal farmers of Southeast Asia. Considered as a nutritionally rich food and fodder, it is also a source of genes for biotic and abiotic stress tolerance including drought, soil acidity and storage pest. Although it spread from its centre of domestication in the Indo-China region to other parts around the world, it never became an important crop anywhere probably because of agronomic disadvantages. Crop improvement for determinate nature, good yield, less variable seed colour, pleasant organoleptic properties and lower antinutrients is required. Scanning of scientific literature indicates that genetic resources with desirable agronomic and nutritional traits exist within the current collection but are spread across countries. Genomic studies in the species indicate that except for insect resistance and aluminium toxicity tolerance, not much attention has been paid to decipher and utilize other stress tolerance and nutritional quality traits. Collaborative efforts towards improving farming, food, trade value and off-farm conservation of rice bean would not only help marginal farmers but will also help to preserve the yet to be explored genomic resources available in this sturdy pulse.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Vigna/crescimento & desenvolvimento , Produção Agrícola/métodos , Abastecimento de Alimentos , Genoma de Planta/genética , Valor Nutritivo , Vigna/genética
15.
Mol Syst Biol ; 11(10): 835, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26519361

RESUMO

Understanding heterogeneous cellular behaviors in a complex tissue requires the evaluation of signaling networks at single-cell resolution. However, probing signaling in epithelial tissues using cytometry-based single-cell analysis has been confounded by the necessity of single-cell dissociation, where disrupting cell-to-cell connections inherently perturbs native cell signaling states. Here, we demonstrate a novel strategy (Disaggregation for Intracellular Signaling in Single Epithelial Cells from Tissue-DISSECT) that preserves native signaling for Cytometry Time-of-Flight (CyTOF) and fluorescent flow cytometry applications. A 21-plex CyTOF analysis encompassing core signaling and cell-identity markers was performed on the small intestinal epithelium after systemic tumor necrosis factor-alpha (TNF-α) stimulation. Unsupervised and supervised analyses robustly selected signaling features that identify a unique subset of epithelial cells that are sensitized to TNF-α-induced apoptosis in the seemingly homogeneous enterocyte population. Specifically, p-ERK and apoptosis are divergently regulated in neighboring enterocytes within the epithelium, suggesting a mechanism of contact-dependent survival. Our novel single-cell approach can broadly be applied, using both CyTOF and multi-parameter flow cytometry, for investigating normal and diseased cell states in a wide range of epithelial tissues.


Assuntos
Apoptose/fisiologia , Células Epiteliais/metabolismo , Sistema de Sinalização das MAP Quinases , Transdução de Sinais , Análise de Célula Única , Fator de Necrose Tumoral alfa/fisiologia , Ativação Enzimática , Humanos
16.
Arch Virol ; 161(7): 1957-61, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27063408

RESUMO

Chilli veinal mottle virus (ChiVMV) causes significant economic loss to chilli cultivation in northeastern India, as well as in eastern Asia. In this study, we have developed a single-tube one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for rapid, sensitive and specific diagnosis of ChiVMV. Amplification could be visualized after adding SYBR Green I (1000×) dye within 60 min under isothermal conditions at 63 °C, with a set of four primers designed based on the large nuclear inclusion protein (NIb) domain of ChiVMV (isolate KC-ML1). The RT-LAMP method was 100 times more sensitive than one-step reverse transcription polymerase chain reaction (RT-PCR), with a detection limit of 0.0001 ng of total RNA per reaction.


Assuntos
Capsicum/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Doenças das Plantas/virologia , Potyvirus/imunologia , Potyvirus/isolamento & purificação , Primers do DNA/genética , Potyvirus/classificação , Potyvirus/genética , Transcrição Reversa , Sensibilidade e Especificidade , Proteínas Virais/genética
18.
J Biol Chem ; 289(11): 7702-17, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24469461

RESUMO

Hydroxynaphthoquinone-based inhibitors of the lysine acetyltransferase KAT3B (p300), such as plumbagin, are relatively toxic. Here, we report that free thiol reactivity and redox cycling properties greatly contribute to the toxicity of plumbagin. A reactive 3rd position in the naphthoquinone derivatives is essential for thiol reactivity and enhances redox cycling. Using this clue, we synthesized PTK1, harboring a methyl substitution at the 3rd position of plumbagin. This molecule loses its thiol reactivity completely and its redox cycling ability to a lesser extent. Mechanistically, non-competitive, reversible binding of the inhibitor to the lysine acetyltransferase (KAT) domain of p300 is largely responsible for the acetyltransferase inhibition. Remarkably, the modified inhibitor PTK1 was a nearly non-toxic inhibitor of p300. The present report elucidates the mechanism of acetyltransferase activity inhibition by 1,4-naphthoquinones, which involves redox cycling and nucleophilic adduct formation, and it suggests possible routes of synthesis of the non-toxic inhibitor.


Assuntos
Proteína p300 Associada a E1A/antagonistas & inibidores , Inibidores Enzimáticos/química , Naftoquinonas/química , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular , Proteína p300 Associada a E1A/química , Células HEK293 , Células HeLa , Humanos , Cinética , Lisina/química , Oxirredução , Estrutura Terciária de Proteína , Espécies Reativas de Oxigênio , Relação Estrutura-Atividade , Compostos de Sulfidrila/química
19.
Biochem Biophys Res Commun ; 462(4): 352-7, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25960297

RESUMO

Recognition of core histone components of chromatin along with chromosomal DNA by a class of small molecule modulators is worth examining to evaluate their intracellular mode of action. A plant alkaloid ellipticine (ELP) which is a putative anticancer agent has so far been reported to function via DNA intercalation, association with topoisomerase II and binding to telomere region. However, its effect upon the potential intracellular target, chromatin is hitherto unreported. Here we have characterized the biomolecular recognition between ELP and different hierarchical levels of chromatin. The significant result is that in addition to DNA, it binds to core histone(s) and can be categorized as a 'dual binder'. As a sequel to binding with histone(s) and core octamer, it alters post-translational histone acetylation marks. We have further demonstrated that it has the potential to modulate gene expression thereby regulating several key biological processes such as nuclear organization, transcription, translation and histone modifications.


Assuntos
Cromatina/efeitos dos fármacos , Elipticinas/farmacologia , Acilação , Cromatina/metabolismo , Dicroísmo Circular , Histonas/metabolismo , Ligação Proteica , Espectrometria de Fluorescência
20.
ChemMedChem ; 19(11): e202400037, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38459687

RESUMO

Non-invasive delivery of drugs is important for the reversal of respiratory diseases essentially by-passing metabolic pathways and targeting large surface area of drug absorption. Here, we study the inhalation of a redox nano medicine namely citrate functionalized Mn3O4 (C-Mn3O4) duly encapsulated in droplet evaporated aerosols for the balancing of oxidative stress generated by the exposure of Chromium (VI) ion, a potential lung carcinogenic agent. Our optical spectroscopic in-vitro experiments demonstrates the efficacy of redox balancing of the encapsulated nanoparticles (NP) for the maintenance of a homeostatic condition. The formation of Cr-NP complex as an excretion of the heavy metal is also demonstrated through optical spectroscopic and high resolution transmission optical microscopy (HRTEM). Our studies confirm the oxidative stress mitigation activity of the Cr-NP complex. A detailed immunological assay followed by histopathological studies and assessment of mitochondrial parameters in pre-clinical mice model with chromium (Cr) induced lung inflammation establishes the mechanism of drug action to be redox-buffering. Thus, localised delivery of C-Mn3O4 NPs in the respiratory tract via aerosols can act as an effective nanotherapeutic agent against oxidative stress induced lung inflammation.


Assuntos
Cromo , Nanopartículas , Oxirredução , Estresse Oxidativo , Pneumonia , Estresse Oxidativo/efeitos dos fármacos , Animais , Camundongos , Cromo/química , Cromo/farmacologia , Pneumonia/tratamento farmacológico , Pneumonia/metabolismo , Nanopartículas/química , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Nanomedicina , Óxidos/química , Óxidos/farmacologia , Sistemas de Liberação de Medicamentos , Ácido Cítrico/química , Humanos , Tamanho da Partícula
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