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1.
Phys Chem Chem Phys ; 25(25): 16712-16717, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37338042

RESUMO

The vibrationally structured 3pz Rydberg excitation is identified and assigned in the VUV absorption spectrum of fenchone with an origin at 6.31 eV, below the prominent 6.4 eV C̃ (nominally 3p) band onset. This feature cannot, however, be observed in (2+1) REMPI spectra, as its relative excitation cross-section is much reduced in a two-photon transition. The 3py and 3px excitation thresholds, found to differ by only 10-30 meV, lie around 6.4 eV corresponding to the first intense C̃ band peak in both VUV and REMPI spectra. Calculations of vertical and adiabatic Rydberg excitation energies, photon absorption cross-sections, and vibrational profiles are used to support these interpretations.

2.
J Biochem Mol Toxicol ; 37(4): e23292, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36527247

RESUMO

Bisphenol A (BPA) is an omnipresent environmental pollutant. Despite being restrictions in-force for its utilization, it is widely being used in the production of polycarbonate plastics and epoxy resins. Direct, low-dose, and long-term exposure to BPA is expected when they are used in the packaging of food products and are used as containers for food consumption. Occupationally, workers are typically exposed to BPA at higher levels and for longer periods during the manufacturing process. BPA is a known endocrine disruptor chemical (EDC), that causes male infertility, which has a negative impact on human life from emotional, physical, and societal standpoints. To minimize the use of BPA in numerous consumer products, efforts and regulations are being made. Despite legislative limits in numerous nations, BPA is still found in consumer products. This paper examines BPA's overall male reproductive toxicity, including its impact on the hypothalamic-pituitary-testicular (HPT) axis, hormonal homeostasis, testicular steroidogenesis, sperm parameters, reproductive organs, and antioxidant defense system. Furthermore, this paper highlighted the role of non-monotonic dose-response (NMDR) in BPA exposure, which will help to improve the overall understanding of the harmful effects of BPA on the male reproductive system.


Assuntos
Disruptores Endócrinos , Masculino , Humanos , Disruptores Endócrinos/toxicidade , Sêmen , Genitália Masculina , Testículo , Compostos Benzidrílicos/toxicidade
3.
Med Vet Entomol ; 37(2): 209-212, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35822871

RESUMO

There are at least three known knockdown resistance (kdr) mutations reported globally in the human head louse Pediculus humanus capitis De Geer (Phthiraptera: Anoplura) that are associated with reduced sensitivity to pyrethroids. However, the prevalence of kdr mutation in head lice is not known in the Indian subcontinent. To identify kdr mutations in the Indian head lice population, the genomic region of the voltage-gated sodium channel gene encompassing IIS1-2 linker to IIS6 segments was PCR-amplified and sequenced from P. humanus capitis samples collected from different geographic localities of India. DNA sequencing revealed the presence of four kdr mutations: M827I, T929I, L932F and L1014F. The presence of a classical kdr mutation L1014F, the most widely reported mutation across insect-taxa associated with the kdr-trait, is being reported for the first time in P. humanus capitis.


Assuntos
Inseticidas , Infestações por Piolhos , Pediculus , Piretrinas , Humanos , Animais , Pediculus/genética , Resistência a Inseticidas/genética , Infestações por Piolhos/veterinária , Mutação , Inseticidas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
4.
Int J Mol Sci ; 24(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38003466

RESUMO

The continuum of antioxidant response dysregulation in aging/oxidative stress-driven Nlrp3 inflammasome activation-mediated inflammatory response is associated with age-related diseases. Peroxiredoxin (Prdx) 6 is a key antioxidant that provides cytoprotection by regulating redox homeostasis. Herein, using lens epithelial cells (LECs) derived from the targeted inactivation of Prdx6 gene and aging lenses, we present molecular evidence that Prdx6-deficiency causes oxidative-driven Nlrp3 inflammasome activation, resulting in pyroptosis in aging/redox active cells wherein Prdx6 availability offsets the inflammatory process. We observed that Prdx6-/- and aging LECs harboring accumulated reactive oxygen species (ROS) showed augmented activation of Nlrp3 and bioactive inflammatory components, like Caspase-1, IL-1ß, ASC and Gasdermin-D. Similar to lipopolysaccharide treatment, oxidative exposure led to further ROS amplification with increased activation of the Nlrp3 inflammasome pathway. Mechanistically, we found that oxidative stress enhanced Kruppel-like factor 9 (Klf9) expression in aging/Prdx6-/- mLECs, leading to a Klf9-dependent increase in Nlrp3 transcription, while the elimination of ROS by the delivery of Prdx6 or by silencing Klf9 prevented the inflammatory response. Altogether, our data identify the biological significance of Prdx6 as an intrinsic checkpoint for regulating the cellular health of aging or redox active LECs and provide opportunities to develop antioxidant-based therapeutic(s) to prevent oxidative/aging-related diseases linked to aberrant Nlrp3 inflammasome activation.


Assuntos
Antioxidantes , Inflamassomos , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Inflamassomos/metabolismo , Estresse Oxidativo , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , Células Epiteliais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
5.
Toxicol Ind Health ; 38(3): 139-150, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35230206

RESUMO

Blood lead level (BLL) is the primary biomarker for lead-exposure monitoring in occupationally exposed workers. We evaluated occupational lead-exposure (OE) impact on cardiopulmonary functions in lead-acid battery recycling unit workers. Seventy-six OE cases and 30 control subjects were enrolled for questionnaire-based socio-demographic, dietary, tobacco usage, and medical history data. Anthropometric measurements, systolic and diastolic blood pressure (SBP and DBP), and pulmonary function tests were performed. Venous blood was collected for BLL, hematological analysis, and biochemical analysis. OE caused a significant increase in BLL, SBP, DBP, and small airways obstruction in lung function tests. It also impaired platelet indices, affected renal and liver biochemical measurements, and promoted oxidative stress and DNA damage. Multilinear regression analysis suggested that BLL affected SBP (ß = 0.314, p = .034) and increased small airways obstruction (FEV1/FVC, ß = -0.37, p = .05; FEV25-75%, ß = -0.351, p = .016). Higher BLL appears to be an independent modulator of hypertension and poor pulmonary function upon occupational lead exposure in lead-acid battery recyclers.


Assuntos
Hipertensão , Exposição Ocupacional , Pressão Sanguínea/fisiologia , Estudos Transversais , Humanos , Hipertensão/etiologia , Chumbo , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise
6.
Exp Eye Res ; 199: 108194, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32822701

RESUMO

A sight threatening, pterygium is a common ocular surface disorders identified by fibrovascular growth of the cornea and induced by variety of stress factors, like ultraviolet (UV) exposure. However, the genes involved in the etiopathogenesis of this disease is not well studied. Herein, we identified the gene expression pattern of pterygium and examined the expression of pterygium-related genes in UV-B-induced human primary cultured corneal epithelial cells (HCEpCs), telomerase immortalized human corneal epithelial (hTCEpi), primary conjunctival fibroblast (HConFs) and primary pterygium fibroblast cells (HPFCs). A careful analysis revealed that the expression of 10 genes was significantly modulated (by > 10-fold). Keratin 24 (KRT24) and matrix metalloproteinase 9 (MMP-9) were dramatically upregulated by 49.446- and 24.214-fold, respectively. Intriguingly, UV-B exposure (50 J/m2) induced the upregulation of the expressions of MMP-9 in corneal epithelial cells such as HCEpCs and hTCEpi. Furthermore, UV-B exposure (100 and/or 200 J/m2) induced the upregulation of the expressions of MMP-9 in fibroblast such as HConFs and HPFCs. The exposure of HCEpCs to 100 and 200 J/m2 UV-B induced significant expressions of KRT24 mRNA. Nevertheless, no expression of KRT24 mRNA was detected in HConFs and HPFCs. The findings provide evidence that the progression of pterygium may involve the modulation of extracellular matrix-related genes and vasculature development and the up-regulation of KRT24 and MMP-9 by UV stress. UV radiation may promote the modulation of these pterygium-related genes and induce the initiation and progression of human pterygium.


Assuntos
Túnica Conjuntiva/metabolismo , Córnea/metabolismo , Regulação da Expressão Gênica/efeitos da radiação , Queratinas Tipo I/genética , Metaloproteinase 9 da Matriz/genética , Pterígio/metabolismo , Raios Ultravioleta , Idoso , Western Blotting , Células Cultivadas , Túnica Conjuntiva/patologia , Córnea/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Queratinas Tipo I/biossíntese , Masculino , Metaloproteinase 9 da Matriz/biossíntese , Pterígio/patologia , RNA/genética
7.
Chemphyschem ; 21(21): 2468-2483, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-32893958

RESUMO

The VUV absorption spectrum of fenchone is re-examined using synchrotron radiation Fourier transform spectrometry, revealing new vibrational structure. Picosecond laser (2+1) resonance enhanced multiphoton ionization (REMPI) spectroscopy complements this, providing an alternative view of the 3spd Rydberg excitation region. These spectra display broadly similar appearance, with minor differences that are largely explained by referring to calculated one- and two-photon electronic excitation cross-sections. Both show good agreement with Franck-Condon simulations of the relevant vibrational structures. Parent ion REMPI ionization yields with both femtosecond and picosecond excitation laser pulses are studied as a function of laser polarization and intensity, the latter providing insight into the relative two-photon excitation and one-photon ionization rates. The experimental circular-linear dichroism observed in the parent ion yields varies strongly between the 3s and 3p Rydberg states, in good overall agreement with the calculated two-photon excitation circular-linear dichroism, while corroborating other evidence that the 3pz sub-state plays no more than a very minor role in the (2+1) REMPI spectrum. Vibrationally resolved photoelectron spectra are recorded with picosecond pulse duration (2+1) REMPI at selected intermediate vibrational excitations. The 3s intermediate state displays a very strong Δv=0 propensity on ionization, but the 3p intermediate evidences more complex vibronic dynamics, and we infer some 3p→3s internal conversion prior to ionization.

8.
Indian J Crit Care Med ; 24(5): 361-362, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32728330

RESUMO

Parvovirus B19 has rarely been associated with acute liver failure (ALF), which has a high mortality. Plasma exchange that usually acts as a bridge to liver transplantation removes toxins, antibodies, cytokines, and can correct coagulopathy while maintaining a euvolemic state. Pediatric data regarding its use are scarce. We report a case of 16-year-old girl with acute liver failure in stage 4 encephalopathy with coagulopathy due to parvovirus B19 who was successfully managed with high-volume therapeutic plasma exchange (TPE). We tried to use it as a treatment modality due to nonavailability of in-hospital transplant facilities. Parvovirus B19 may be an underdiagnosed cause of acute viral hepatitis. Therapeutic plasma exchange can act as a bridge to liver transplant (LT) or bridge to recovery especially in self-limiting illnesses such as viral hepatitis. HOW TO CITE THIS ARTICLE: Singh DP, Agarwal S, Singh R, Nandan D, Gupta A. Therapeutic Plasma Exchange in Parvovirus B19-induced Acute Hepatic Failure. Indian J Crit Care Med 2020;24(5):361-362.

10.
Arch Toxicol ; 92(5): 1767-1783, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29623357

RESUMO

Chronic obstructive pulmonary disease (COPD) is predicted to become the third leading cause of death and disability worldwide by 2030; with cigarette smoking (active or passive) being one of the chief cause of its occurrence. Cigarette smoke exposure has been found to result in excessive inflammation and tissue injury, which might lead to COPD, although the exact pathophysiology of the disease remains elusive. While previous studies have demonstrated the role of membrane-bound Toll-like receptors (TLRs) in cigarette smoke (CS)-induced inflammation, scant information is available about the role of cytosolic NOD-like receptors (NLRs) in regulating CS-mediated inflammatory responses. Thus, we investigated the role of NLRP10 and NLRP12 in regulating inflammatory responses in human alveolar type II epithelial cells (A549) and human monocytic cells (THP-1) in response to a challenge with cigarette smoke extract (CSE). We observed CSE-mediated increase in caspase-1 activity; production of IL-1ß and IL-18; and expression of NLRP10 and NLRP12 in A549 and THP-1 cells. Interestingly, immunofluorescence imaging results demonstrated an increase in the membrane recruitment of NLRP10 and NLRP12 proteins in CSE-challenged A549 cells. We also observed an increase in the expression of lipid raft proteins (caveolin-1, caveolin-2, and flotillin-1) and an induction of lipid raft assembly following CSE-exposure in A549 cells. Lipid rafts are cholesterol-rich membrane microdomains well known to act as harbours for signalling molecules. Here we demonstrate  the recruitment of NLRP10 and NLRP12 in lipid raft entities as well as the interaction of NLRP12 with the lipid raft protein caveolin-1 in CSE-challenged A549 cells. Furthermore, enrichment of lipid raft entities with poly-unsaturated fatty acids (PUFA) rescued A549 cells from CSE-mediated membrane recruitment of NLRP10 and NLRP12, and also from inflammatory responses and inflammasome activation. Enrichment of membrane microdomains with PUFA was able to reverse filipin (chemical agent used for disrupting lipid rafts)-mediated enhanced inflammation in CSE-challenged A549 cells. Overall, our findings unveil a novel mechanism by identifying an important role of membrane microdomains (lipid rafts) in regulating CSE-induced inflammation and NLRP10/NLRP12-dependent signalling in A549 cells.


Assuntos
Proteínas de Transporte/metabolismo , Fumar Cigarros/efeitos adversos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microdomínios da Membrana/efeitos dos fármacos , Células A549 , Proteínas Adaptadoras de Transdução de Sinal , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/genética , Caspase 1/metabolismo , Linhagem Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Ácidos Graxos Insaturados/farmacologia , Filipina/efeitos adversos , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microdomínios da Membrana/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Int J Mol Sci ; 19(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304871

RESUMO

Transforming growth factor (TGF) ß and fibroblast growth factor (FGF) 2 are related to the development of posterior capsule opacification (PCO) after lens extraction surgery and other processes of epithelial⁻mesenchymal transition (EMT). Oxidative stress seems to activate TGF ß1 largely through reactive oxygen species (ROS) production, which in turn alters the transcription of several survival genes, including lens epithelium-cell derived growth factor (LEDGF). Higher ROS levels attenuate LEDGF function, leading to down-regulation of peroxiredoxin 6 (Prdx6). TGF ß is regulated by ROS in Prdx6 knock-out lens epithelial cells (LECs) and induces the up-regulation of tropomyosins (Tpms) 1/2, and EMT of LECs. Mouse and rat PCO are accompanied by elevated expression of Tpm2. Further, the expression of Tpm1/2 is induced by TGF ß2 in LECs. Importantly, we previously showed that TGF ß2 and FGF2 play regulatory roles in LECs in a contrasting manner. An injury-induced EMT of a mouse lens as a PCO model was attenuated in the absence of Tpm2. In this review, we present findings regarding the roles of TGF ß and FGF2 in the differential regulation of EMT in the lens. Tpms may be associated with TGF ß2- and FGF2-related EMT and PCO development.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Cristalino/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Animais , Biomarcadores , Opacificação da Cápsula/etiologia , Opacificação da Cápsula/metabolismo , Opacificação da Cápsula/patologia , Catarata/etiologia , Catarata/metabolismo , Catarata/patologia , Transição Epitelial-Mesenquimal/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Peroxirredoxina VI/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tropomiosina/metabolismo , Cicatrização
12.
Int J Mol Sci ; 19(11)2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413111

RESUMO

Sumoylation is a downstream effector of aging/oxidative stress; excess oxidative stress leads to dysregulation of a specificity protein1 (Sp1) and its target genes, such as Peroxiredoxin 6 (Prdx6), resulting in cellular damage. To cope with oxidative stress, cells rely on a signaling pathway involving redox-sensitive genes. Herein, we examined the therapeutic efficacy of the small molecule Ginkgolic acid (GA), a Sumoylation antagonist, to disrupt aberrant Sumoylation signaling in human and mouse lens epithelial cells (LECs) facing oxidative stress or aberrantly expressing Sumo1 (small ubiquitin-like modifier). We found that GA globally reduced aberrant Sumoylation of proteins. In contrast, Betulinic acid (BA), a Sumoylation agonist, augmented the process. GA increased Sp1 and Prdx6 expression by disrupting the Sumoylation signaling, while BA repressed the expression of both molecules. In vitro DNA binding, transactivation, Sumoylation and expression assays revealed that GA enhanced Sp1 binding to GC-boxes in the Prdx6 promoter and upregulated its transcription. Cell viability and intracellular redox status assays showed that LECs pretreated with GA gained resistance against oxidative stress-driven aberrant Sumoylation signaling. Overall, our study revealed an unprecedented role for GA in LECs and provided new mechanistic insights into the use of GA in rescuing LECs from aging/oxidative stress-evoked dysregulation of Sp1/Prdx6 protective molecules.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Peroxirredoxina VI/genética , Salicilatos/farmacologia , Fator de Transcrição Sp1/genética , Animais , Proteínas de Ligação a DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Cristalino/citologia , Cristalino/efeitos dos fármacos , Cristalino/metabolismo , Camundongos , Triterpenos Pentacíclicos , Regiões Promotoras Genéticas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sumoilação/efeitos dos fármacos , Triterpenos/farmacologia , Ácido Betulínico
13.
J Cell Mol Med ; 21(5): 916-928, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27976512

RESUMO

Transforming growth factor (TGF) ß2 and fibroblast growth factor (FGF) 2 are involved in regulation of posterior capsule opacification (PCO) and other processes of epithelial-mesenchymal transition (EMT) such as cancer progression, wound healing and tissue fibrosis as well as normal embryonic development. We previously used an in vivo rodent PCO model to show the expression of tropomyosin (Tpm) 1/2 was aberrantly up-regulated in remodelling the actin cytoskeleton during EMT. In this in vitro study, we show the Tpms family of cytoskeleton proteins are involved in regulating and stabilizing actin microfilaments (F-actin) and are induced by TGFß2 during EMT in lens epithelial cells (LECs). Importantly, we found TGFß2 and FGF2 played contrasting roles. Stress fibre formation and up-regulation of α-smooth muscle actin (αSMA) induced by TGFß2 could be reversed by Tpm1/2 knock-down by siRNA. Expression of Tpm1/2 and stress fibre formation induced by TGFß2 could be reversed by FGF2. Furthermore, FGF2 delivery to TGFß-treated LECs perturbed EMT by reactivating the mitogen-activated protein kinase (MAPK)/ extracellular signal-regulated kinase (ERK) pathway and subsequently enhanced EMT. Conversely, MEK inhibitor (PD98059) abated the FGF2-mediated Tpm1/2 and αSMA suppression. However, we found that normal LECs which underwent EMT showed enhanced migration in response to combined TGFß and FGF2 stimulation. These findings may help clarify the mechanism reprogramming the actin cytoskeleton during morphogenetic EMT cell proliferation and fibre regeneration in PCO. We propose that understanding the physiological link between levels of FGF2, Tpm1/2 expression and TGFßs-driven EMT orchestration may provide clue(s) to develop therapeutic strategies to treat PCO based on Tpm1/2.


Assuntos
Opacificação da Cápsula/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fator de Crescimento Transformador beta2/farmacologia , Tropomiosina/metabolismo , Actinas/metabolismo , Animais , Biomarcadores/metabolismo , Opacificação da Cápsula/patologia , Movimento Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Cápsula do Cristalino/efeitos dos fármacos , Cápsula do Cristalino/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Fenótipo , RNA Interferente Pequeno/metabolismo , Transfecção
14.
Cell Biol Toxicol ; 33(5): 429-455, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28275881

RESUMO

Infectious diseases pose major socioeconomic and health-related threats to millions of people across the globe. Strategies to combat infectious diseases derive from our understanding of the complex interactions between the host and specific bacterial, viral, and fungal pathogens. Lipid rafts are membrane microdomains that play important role in life cycle of microbes. Interaction of microbial pathogens with host membrane rafts influences not only their initial colonization but also their spread and the induction of inflammation. Therefore, intervention strategies aimed at modulating the assembly of membrane rafts and/or regulating raft-directed signaling pathways are attractive approaches for the. management of infectious diseases. The current review discusses the latest advances in terms of techniques used to study the role of membrane microdomains in various pathological conditions and provides updated information regarding the role of membrane rafts during bacterial, viral and fungal infections.


Assuntos
Doenças Transmissíveis/fisiopatologia , Microdomínios da Membrana/fisiologia , Animais , Infecções Bacterianas/microbiologia , Infecções Bacterianas/fisiopatologia , Doenças Transmissíveis/microbiologia , Humanos , Microdomínios da Membrana/metabolismo , Microdomínios da Membrana/microbiologia , Transdução de Sinais , Viroses/microbiologia , Viroses/fisiopatologia
15.
Am J Physiol Cell Physiol ; 310(1): C1-16, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26447207

RESUMO

Oxidative stress or reduced expression of naturally occurring antioxidants during aging has been identified as a major culprit in neuronal cell/tissue degeneration. Peroxiredoxin (Prdx) 6, a protective protein with GSH peroxidase and acidic calcium-independent phospholipase A2 activities, acts as a rheostat in regulating cellular physiology by clearing reactive oxygen species (ROS) and thereby optimizing gene regulation. We found that under stress, the neuronal cells displayed reduced expression of Prdx6 protein and mRNA with increased levels of ROS, and the cells subsequently underwent apoptosis. Using Prdx6 fused to TAT transduction domain, we showed evidence that Prdx6 was internalized in human brain cortical neuronal cells, HCN-2, and mouse hippocampal cells, HT22. The cells transduced with Prdx6 conferred resistance against the oxidative stress inducers paraquat, H2O2, and glutamate. Furthermore, Prdx6 delivery ameliorated damage to neuronal cells by optimizing ROS levels and overstimulation of NF-κB. Intriguingly, transduction of Prdx6 increased the expression of endogenous Prdx6, suggesting that protection against oxidative stress was mediated by both extrinsic and intrinsic Prdx6. The results demonstrate that Prdx6 expression is critical to protecting oxidative stress-evoked neuronal cell death. We propose that local or systemic application of Prdx6 can be an effective means of delaying/postponing neuronal degeneration.


Assuntos
Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Peroxirredoxina VI/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Criança , Citoproteção , Relação Dose-Resposta a Droga , Endocitose , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/metabolismo , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais , Transfecção
16.
Langmuir ; 32(42): 10808-10814, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27709958

RESUMO

For over five decades, an enhancement in pool boiling heat transfer has been achieved by altering the surface wetting, wickability, roughness, nucleation site density, and providing separate liquid/vapor pathways. In this work, a new enhancement mechanism based on the early evaporation of the microlayer is discovered and validated. The microlayer is a thin liquid film present at the base of a vapor bubble. The presence of microridges on the silicon dioxide surface partitions the microlayer and disconnects it from the bulk liquid, causing it to evaporate sooner, thus leading to increase in the bubble growth rate, heat transfer, departure frequency, and critical heat flux (CHF). Compared to a plain surface, an ∼120% enhancement in CHF is obtained with only an ∼18% increase in surface area. A CHF enhancement map is developed on the basis of the ridge height and spacing, resulting in three regions of full, partial, and no enhancement. The new mechanism is validated by comparing the growth rate of a laser-created vapor bubble on a ridge-structured surface and a plain surface, and the corresponding prediction of the CHF enhancement is found to be in good agreement with the experimental boiling data. This discovery opens up a new field of CHF enhancement and can potentially be coupled with existing techniques to further push the limits of boiling heat transfer.

17.
J Sci Food Agric ; 95(2): 359-66, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24796530

RESUMO

BACKGROUND: Detection of improper labelling of raw and processed seafood is of global importance for reducing commercial fraud and enhancing food safety. Crabs are crustaceans with intricate morphological as well as genetic divergence among species and are popular as seafood in restaurants. Owing to the high number of crab species available, it can be difficult to identify those included in particular food dishes, thus increasing the chance of supersession. DNA barcoding is an advanced technology for detecting improper food labelling and has been used successfully to authenticate seafood. RESULTS: This study identified 11 edible crab species from India by classical taxonomy and developed molecular barcodes with the cytochrome c oxidase I (COI) gene. These barcodes were used as reference barcodes for detecting any improper labelling of 50 restaurant crab samples. Neighbour-joining tree analysis with COI barcodes showed distinct clusters of restaurant samples with respective reference species. The study demonstrated 100% improper labelling of restaurant samples to cover up acts of inferior crab supersession. CONCLUSION: DNA barcoding successfully identified 11 edible crabs in accordance with classical taxonomy and discerned improper crab food labelling in restaurants of India.


Assuntos
Braquiúros/genética , Código de Barras de DNA Taxonômico , DNA/análise , Complexo IV da Cadeia de Transporte de Elétrons/genética , Rotulagem de Alimentos , Restaurantes , Frutos do Mar , Animais , Humanos , Índia , Filogenia , Especificidade da Espécie
18.
Br J Nutr ; 112(9): 1447-58, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25234097

RESUMO

Several epidemiological studies have shown that the consumption of finger millet (FM) alleviates diabetes-related complications. In the present study, the effect of finger millet whole grain (FM-WG) and bran (FM-BR) supplementation was evaluated in high-fat diet-fed LACA mice for 12 weeks. Mice were divided into four groups: control group fed a normal diet (10 % fat as energy); a group fed a high-fat diet; a group fed the same high-fat diet supplemented with FM-BR; a group fed the same high-fat diet supplemented with FM-WG. The inclusion of FM-BR at 10 % (w/w) in a high-fat diet had more beneficial effects than that of FM-WG. FM-BR supplementation prevented body weight gain, improved lipid profile and anti-inflammatory status, alleviated oxidative stress, regulated the expression levels of several obesity-related genes, increased the abundance of beneficial gut bacteria (Lactobacillus, Bifidobacteria and Roseburia) and suppressed the abundance of Enterobacter in caecal contents (P≤ 0·05). In conclusion, FM-BR supplementation could be an effective strategy for preventing high-fat diet-induced changes and developing FM-BR-enriched functional foods.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Eleusine , Inflamação/prevenção & controle , Intestinos/microbiologia , Obesidade/metabolismo , Estresse Oxidativo , Tecido Adiposo/metabolismo , Animais , Carga Bacteriana , Glicemia/metabolismo , Suplementos Nutricionais , Regulação da Expressão Gênica , Lipídeos/sangue , Fígado/metabolismo , Camundongos , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Nutrigenômica , Obesidade/genética , Pâncreas/metabolismo , Sementes , Aumento de Peso
19.
Cell Death Discov ; 10(1): 296, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909054

RESUMO

The physiological quantum of stress-inducible transcriptional protein, Lens Epithelium-Derived Growth Factor (LEDGF), is vital for the maintenance of cellular physiology. Erratic epigenetic reprogramming in response to oxidative stress or with advancing age is found to be a major cause in the gene silencing, leading to pathobiologies. Using aging human (h) eye lens/lens epithelial cells (LECs) coupled with redox-active Peroxiredoxin 6 (Prdx6)-deficient (Prdx6-/-) mLECs as model systems, herein, we showed that in aging/oxidative stress, the human LEDGF gene was regulated by unique methylation patterns of CGs nucleotides within and around the Sp1 binding site(s) of CpG island of the LEDGF promoter (-170 to -27nts). The process caused the repression of LEDGF and its target, Hsp27, resulting in reactive oxygen species (ROS) amplification and cellular insults. This phenomenon was opposed to the unmethylated promoter in LECs. Clinically, we observed that the loss of LEDGF in the Prdx6-/- mLECs or aging lenses/LECs, correlating with increased expression of DNMT1, DNMT3a, and DNMT3b along with the methyl CpG binding protein 2 (MeCP2). Upon oxidative stress, the expression of these molecules was increased with the dramatic reduction in LEDGF expression. While demethylating agent, 5-Aza deoxycytidine (5-AzaC) transposed the aberrant methylation status, and revived LEDGF and Hsp27 expression. Mechanistically, the chloramphenicol acetyltransferase (CAT) reporter gene driven by the LEDGF promoter (-170/ + 35) and ChIP assays uncovered that 5-AzaC acted on GC/Sp1 sites to release LEDGF transcription. The data argued, for the first time, that de novo methylation of CGs around and within Sp1 sites of the CpG island directly disrupted Sp1 activity, which ensued in LEDGF repression and its biological functions. The findings should improve our understanding of cellular insults-associated with aberrant DNMTs-mediated LEDGF's activity, and can offer strategies for therapeutic intervention to halt aging/oxidative stress-induced abnormalities.

20.
J Phys Chem Lett ; 15(3): 834-839, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38235964

RESUMO

The broadening in photoelectron spectra of polymers can be attributed to several factors, such as light source spread, spectrometer resolution, the finite lifetime of the hole state, and solid-state effects. Here, for the first time, we set up a computational protocol to assess the peak broadening induced for both core and valence levels by solid-state effects in four amorphous polymers by using a combination of density functional theory, many-body perturbation theory, and classical polarizable embedding. We show that intrinsic local inhomogeneities in the electrostatic environment induce a Gaussian broadening of 0.2-0.7 eV in the binding energies of both core and semivalence electrons, corresponding to a full width at half-maximum (FWHM) of 0.5-1.7 eV for the investigated systems. The induced broadening is larger in acrylate-based than in styrene-based polymers, revealing the crucial role of polar groups in controlling the roughness of the electrostatic landscape in the solid matrix.

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