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1.
Bioconjug Chem ; 35(9): 1343-1351, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39223465

RESUMO

The production of recombinant proteins has become a focal point in biotechnology, with potential applications in catalysis, therapeutics, and diagnostics. Before their application, these proteins undergo cumbersome downstream processing, including multiple resin-based chromatography steps (ion exchange or affinity-based) to isolate the protein of interest from host cell proteins, which are more abundant. These methods often involve (1) nonspecific binding of host cell proteins onto the resin, (2) a trial and error approach in determining elution conditions for the protein of interest, and (3) complex functionalization of the resin. These processes are also further supplemented with additional processing steps including buffer exchange through dialysis or desalting. Despite the prevalence and need for proteins, challenges persist in optimizing elution conditions and minimizing downstream processing steps, which contribute to the overall cost, impeding their translation into the market. To address these challenges, there has been a growing interest in stimuli-responsive purification systems, which allow for precise control and modulation of the purification process for protein recovery by altering their properties or behavior in response to specific external conditions, such as heat, light, or chemicals. We have developed a light-activated molecular purification (LAMP) system, a stimuli-responsive chromatography technique where the purification of recombinant proteins is triggered by light. We employed a photocleavable protein (PhoCl1) that binds specifically to Ni-NTA resin through a hexa-histidine tag at its N-terminus. We harnessed the ability of PhoCl1 to undergo photocleavage into two fragments for the development of LAMP. To demonstrate LAMP, the protein of interest (POI) is genetically fused to the C-terminus of PhoCl1. The exposure to 405 nm light (1.5 mW cm-2 for 12 h) results in the release of POI into the supernatant. We showcased the potential of LAMP by purifying highly charged green fluorescent proteins and an enzyme, riboflavin kinase. Our custom-built violet light LED setup achieved more than 50% light-induced photocleavage of the fusion constructs, resulting in the release of more than 30% of the POI into the supernatant, with the remainder retained within the resin. All the proteins purified using LAMP were more than 90% pure. Moreover, the comparison of the riboflavin kinase purified through LAMP and the traditional chromatography (Ni-NTA affinity method) revealed no significant changes in the activity levels. These highlight the broad potential of LAMP in providing a facile, yet robust stimuli-responsive protein purification technique, which leverages the potential of light to purify the proteins and overcome the limitations of current conventional chromatography systems.


Assuntos
Luz , Proteínas Recombinantes , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Cromatografia de Afinidade/métodos , Humanos
2.
Cardiol Young ; 32(7): 1151-1153, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34732274

RESUMO

BACKGROUND: The present study aimed to quantify the burden of structural heart disease in Nepali children. METHODS: We performed a school-based cross-sectional echocardiographic screening study with cluster random sampling among children 5-16 years of age. RESULTS: Between December 2012 and January 2019, 6573 children (mean age 10.6 ± 2.9 years) from 41 randomly selected schools underwent echocardiographic screening. Structural heart disease was detected in 14.0 per 1000 children (95% CI 11.3-17.1) and was congenital in 3.3 per 1000 (95% CI 2.1-5.1) and rheumatic in 10.6 per 1000 (95% CI 8.3-13.4). Rates of rheumatic heart disease were higher among children attending public as compared to private schools (OR 2.8, 95% CI 1.6-5.2, p = 0.0001). CONCLUSION: Rheumatic heart disease accounted for three out of four cases of structural heart disease and was more common among children attending public as compared to private schools.


Assuntos
Cardiopatia Reumática , Adolescente , Criança , Estudos Transversais , Ecocardiografia , Humanos , Programas de Rastreamento , Prevalência , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/epidemiologia , Instituições Acadêmicas
4.
JNMA J Nepal Med Assoc ; 61(264): 651-653, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289820

RESUMO

Introduction: Stress is the response of body to any change. The end stage of renal disease and the process of haemodialysis treatment are long-term stressors that alter patients' well-being and everyday lifestyle. The aim of this study was to find out the prevalence of moderate stress levels among patients undergoing hemodialysis in a tertiary care centre. Methods: A descriptive cross-sectional study was conducted among patients undergoing hemodialysis from 1 October 2021 to 30 September 2022. Ethical clearance from the Institutional Review Committee. Patients undergoing maintenance haemodialysis for at least 3 months were included in the study. Convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval. Results: Among 118 patients, 82 (69.49%) (61.18-77.80, 95% Confidence Interval) had moderate stress levels, out of which 51 (62.20%) were male and 31 (37.80%) were female. Conclusions: The prevalence of moderate stess level was found to be higher than other studies done in similar settings. Keywords: hemodialysis; prevalence; psychiatric disorders.


Assuntos
Transtornos Mentais , Humanos , Feminino , Masculino , Centros de Atenção Terciária , Estudos Transversais , Diálise Renal , Projetos de Pesquisa
5.
Environ Toxicol ; 27(9): 549-55, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21254321

RESUMO

Acute neurotoxic effects of high-dose methylmercury (MeHg) in humans have been well documented in the scientific literature. However, low-dose effects are less well described. This study was designed to evaluate the effects of low-dose MeHg (<100 nM) on human brain cells in a tissue culture model. Neuroblastoma (NB) cells (SH-SY5Y) were used in the cell culture model to study low-dose effects of MeHg on cell growth, cell survival, reactive oxygen species (ROS), and the phosphorylation of tau protein, as a measure of potential markers of cellular events associated with tauopathies. When cells were incubated in culture with MeHg (50 and 100 nM), there were significant decreases in cell viability as well as significant increase in ROS generation as determined by fluorescent dye analysis (H(2)DCFDA). Furthermore, a concomitant decrease in glutathione levels to 25% of control was observed at both 50 and 100 nM MeHg. In addition, the level of phosphorylated tau was significantly increased after treatment at both 50 and 100 nM MeHg, compared with controls. Pretreatment of NB cells with the antioxidant, N-acetylcysteine (1.25 mM) and the calpain inhibitor, MDL-28170 (10 µM), significantly attenuated the effects of MeHg (50 and 100 nM) on cell viability as well as on tau phosphorylation. These results indicate that low-dose MeHg toxicity may be related to an induction of tau phosphorylation through an oxidative stress-dependent mechanism and that blockade of this pathway may attenuate the toxic effects of MeHg.


Assuntos
Compostos de Metilmercúrio/toxicidade , Neuroblastoma/patologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas tau/química , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Butionina Sulfoximina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dipeptídeos/farmacologia , Glutationa/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neuroblastoma/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo
6.
J Clin Endocrinol Metab ; 107(5): 1328-1336, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35018440

RESUMO

CONTEXT: Wolfram syndrome (WFS) is a rare autosomal recessive disorder characterized by juvenile-onset diabetes, diabetes insipidus, optic atrophy, deafness, and progressive neurodegeneration. However, due to the progressive nature of the disease and a lack of complete clinical manifestations, a confirmed diagnosis of WFS at the time of onset of diabetes is a challenge. OBJECTIVE: With WFS1 rare heterozygous variants reported in diabetes, there is a need for comprehensive genetic screening strategies for the early diagnosis of WFS and delineating the phenotypic spectrum associated with the WFS1 gene variants in young-onset diabetes. METHODS: This case series of 11 patients who were positive for WFS1 variants were identified with next-generation sequencing (NGS)-based screening of 17 genemonogenic diabetes panel. These results were further confirmed with Sanger sequencing. RESULTS: 9 out of 11 patients were homozygous for pathogenic/likely pathogenic variants in the WFS1 gene. Interestingly, 3 of these probands were positive for the novel WFS1 (NM_006005.3): c.1107_1108insA (p.Ala370Serfs*173) variant, and haplotype analysis suggested a founder effect in 3 families from Southern India. Additionally, we identified 2 patients with young-onset diabetes who were heterozygous for a likely pathogenic variant or a variant of uncertain significance in the WFS1 gene. CONCLUSION: These results project the need for NGS-based parallel multigene testing as a tool for early diagnosis of WFS and identify heterozygous WFS1 variants implicated in young-onset diabetes.


Assuntos
Proteínas de Membrana , Síndrome de Wolfram , Feminino , Humanos , Índia/epidemiologia , Masculino , Proteínas de Membrana/genética , Mutação , Fenótipo , Síndrome de Wolfram/diagnóstico , Síndrome de Wolfram/genética , Síndrome de Wolfram/patologia
7.
Open Heart ; 8(1)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33820851

RESUMO

INTRODUCTION: Systematic echocardiographic screening of children in regions with an endemic pattern of rheumatic heart disease allows for the early detection of valvular lesions suggestive of subclinical rheumatic heart disease. The natural course of latent rheumatic heart disease is, however, incompletely understood at this time. METHODS: We performed a prospective cohort study of children detected to have echocardiographic evidence of definite or borderline rheumatic heart disease according to the World Heart Federation Criteria. RESULTS: Among 53 children found to have definite (36) or borderline (17) rheumatic heart disease, 44 (83%) children underwent follow-up at a median of 1.9 years (IQR 1.1-4.5). The median age of the children was 11 years (IQR 9-14) and 34 (64.2%) were girls. Among children with definite rheumatic heart disease, 21 (58.3%) were adherent to secondary antibiotic prophylaxis, 7 (19.4%) were not, information on adherence was missing in 2 (5.6%) children and 6 (16.7%) were lost to follow-up. Regression of disease was observed in 10 children (27.8%), whereas 20 children (55.6%) had stable disease. Among children adherent to secondary prophylaxis, seven (33.3%) showed regression of disease. Among children with borderline disease, seven (41.2%) showed regression of disease, three (17.6%) progression of disease, four (23.5%) remained stable and three (17.6%) were lost to follow-up. On univariate analysis, we identified no predictors of disease regression, and no predictors for lost to follow-up or non-adherence with secondary antibiotic prophylaxis. CONCLUSION: Definite rheumatic heart disease showed regression in one in four children. Borderline disease was spontaneously reversible in less than half of the children and progressed to definite rheumatic heart disease in one in five children. TRIAL REGISTRATION NUMBER: NCT01550068.


Assuntos
Diagnóstico Precoce , Programas de Rastreamento/métodos , Cardiopatia Reumática/epidemiologia , População Rural , População Urbana , Adolescente , Criança , Progressão da Doença , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Morbidade/tendências , Nepal/epidemiologia , Estudos Prospectivos , Cardiopatia Reumática/diagnóstico , Fatores de Tempo
8.
JNMA J Nepal Med Assoc ; 59(235): 243-247, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-34506437

RESUMO

INTRODUCTION: D-dimer is currently the best available marker for COVID-19 associated hemostatic abnormalities. This study aims to find out the prevelance of elevated D-dimer levels in confirmed COVID-19 cases in intensive care unit of a tertiary care hospital of western Nepal. METHODS: This descriptive cross-sectional study was conducted among 95 patients admitted to COVID Intensive Care Unit of a teriary care centre from August 2020 to January 2021 after taking ethical clearence from Institutional Review Committee in order to determine the D-dimer levels in confirmed COVID-19 cases. D-dimer value was measured at the admission and the highest D-dimer value was recorded during the course of hospital stay with the risk of mortality in confirmed COVID-19 cases. The normal range of D-dimer was taken as <0.35 mg/dl as per our hospital laboratory standards. Convenience sampling method was used. Data entry and descriptive analysis were done in Statistical Package for the Social Sciences version 25.0, point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data. RESULTS: Out of total 95 cases of COVID-19 included in this study, 25 (89.3%) patients with age ≥ 65 years and 42 (62.69%) patients aged <65 years had elevated D-dimer on admission. Data showed that 29 (67.4%) patients having elevated D-dimer at admission had mortality. CONCLUSIONS: Elevated D-dimer levels was frequently seen in patients admitted in Intensive Care Unit with COVID-19. Our study suggested that measurement of D-dimer may guide in clinical decision making.


Assuntos
COVID-19 , Idoso , Estudos Transversais , Produtos de Degradação da Fibrina e do Fibrinogênio , Humanos , Unidades de Terapia Intensiva , Nepal/epidemiologia , Prevalência , SARS-CoV-2 , Centros de Atenção Terciária
9.
JAMA Cardiol ; 6(4): 420-426, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33471029

RESUMO

Importance: Echocardiographic screening allows for early detection of subclinical stages of rheumatic heart disease among children in endemic regions. Objective: To investigate the effectiveness of systematic echocardiographic screening in combination with secondary antibiotic prophylaxis on the prevalence of rheumatic heart disease. Design, Setting, and Participants: This cluster randomized clinical trial included students 9 to 16 years of age attending public and private schools in urban and rural areas of the Sunsari district in Nepal that had been randomly selected on November 17, 2012. Echocardiographic follow-up was performed between January 7, 2016, and January 3, 2019. Interventions: In the experimental group, children underwent systematic echocardiographic screening followed by secondary antibiotic prophylaxis in case they had echocardiographic evidence of latent rheumatic heart disease. In the control group, children underwent no echocardiographic screening. Main Outcomes and Measures: Prevalence of the composite of definite or borderline rheumatic heart disease according to the World Heart Federation criteria in experimental and control schools as assessed 4 years after intervention. Results: A total of 35 schools were randomized to the experimental group (n = 19) or the control group (n = 16). After a median of 4.3 years (interquartile range [IQR], 4.0-4.5 years), 17 of 19 schools in the experimental group (2648 children; median age at follow-up, 12.1 years; IQR, 10.3-12.5 years; 1308 [49.4%] male) and 15 of 16 schools in the control group (1325 children; median age at follow-up, 10.6 years; IQR, 10.0-12.5 years; 682 [51.5%] male) underwent echocardiographic follow-up. The prevalence of definite or borderline rheumatic heart disease was 10.8 per 1000 children (95% CI, 4.7-24.7) in the control group and 3.8 per 1000 children (95% CI, 1.5-9.8) in the experimental group (odds ratio, 0.34; 95% CI, 0.11-1.07; P = .06). The prevalence in the experimental group at baseline had been 12.9 per 1000 children (95% CI, 9.2-18.1). In the experimental group, the odds ratio of definite or borderline rheumatic heart disease at follow-up vs baseline was 0.29 (95% CI, 0.13-0.65; P = .008). Conclusions and Relevance: School-based echocardiographic screening in combination with secondary antibiotic prophylaxis in children with evidence of latent rheumatic heart disease may be an effective strategy to reduce the prevalence of definite or borderline rheumatic heart disease in endemic regions. Trial Registration: ClinicalTrials.gov Identifier: NCT01550068.


Assuntos
Ecocardiografia/métodos , Programas de Rastreamento/métodos , Cardiopatia Reumática/diagnóstico , Adolescente , Antibioticoprofilaxia/métodos , Criança , Feminino , Humanos , Masculino , Nepal/epidemiologia , Prevalência , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/epidemiologia , Cardiopatia Reumática/prevenção & controle
10.
Cancer Sci ; 101(1): 103-11, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19811499

RESUMO

The molecular mechanisms involved in prostate cancer (PC) metastasis and bone remodeling are poorly understood. We recently reported that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) mediates transcriptional regulation and activation of bone morphogenetic protein (BMP)-2 signaling by nuclear factor (NF)-kappaB in bone metastatic prostate cancer cells. In the present study, we demonstrate that NF-kappaB, whether activated by recombinant human tumor necrosis factor (TNF)-alpha or by ectopic expression of the p65 subunit, is involved in extracellular matrix adhesion and invasion of osteotropic PC-3 and C4-2B, but not LNCaP, cells. The enhanced metastatic potential was associated with transcriptional upregulation of osteopontin, osteocalcin, and collagen IA1 in osteotropic PC cells, suggesting their role in osteomimicry of PC cells. Unlike BMP-4, BMP-2 protein enhanced the invasive properties of C4-2B cells, but not in LNCaP cells. Also, this effect was nullified by Noggin. In addition, BMP-2 mediates TNF-alpha-induced invasion of C4-2B cells in a NF-kappaB-dependent fashion. TNF-alpha or conditioned media (CM) of TNF-alpha-stimulated C4-2B cells upregulated BMP-2 and BMP-dependent Smad transcripts and inhibited receptor activator of NF-kappaB ligand transcripts in RAW 264.7 preosteoclast cells, respectively, implying that this factor may contribute to suppression of osteoclastogenesis via direct and paracrine mechanisms. In contrast, CM of TNF-alpha-stimulate or BMP2-stimulated C4-2B cells induced in vitro mineralization of MC3T3-E1 osteoblast cells in a BMP-2-dependent and NF-kappaB-dependent manner, respectively. Taken together, the results suggest that mutual interactions between these factors may be pivotal not only in enhancing the osteomimicry and metastatic potential of PC cells, but also in bone remodeling and in shifting the balance from osteoclastogenesis towards osteoblastogenesis.


Assuntos
Proteína Morfogenética Óssea 2/fisiologia , Calcificação Fisiológica , NF-kappa B/fisiologia , Osteoblastos/fisiologia , Neoplasias da Próstata/patologia , Fator de Necrose Tumoral alfa/fisiologia , Diferenciação Celular , Linhagem Celular Tumoral , Humanos , Masculino , Metástase Neoplásica , Osteoblastos/citologia , Ligante RANK/genética
11.
BJU Int ; 106(1): 78-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20002674

RESUMO

STUDY TYPE: Aetiology (case control) Level of Evidence 3b OBJECTIVE To evaluate the effect of N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension (HT) on erectile function in the rat and determine if the phosphodiesterase (PDE)-5 inhibitor, sildenafil, can reverse the effects of nitric oxide (NO) deficiency, as HT is a risk factor for erectile dysfunction (ED) and the NO synthase (NOS) inhibitor L-NAME induces NO-deficient HT. MATERIALS AND METHODS: Thirty-six adult Sprague-Dawley male rats were divided into three groups, i.e. a control, L-NAME-HT (40 mg/rat/day in the drinking water for 4 weeks), and sildenafil-treated L-NAME-HT (1.5 mg/rat/day sildenafil, by oral gavage concomitantly with L-NAME). The erectile response expressed as a ratio of intracavernosal pressure (ICP)/mean arterial pressure (MAP), evaluated after electrical stimulation of the right cavernous nerve. The isometric tension of corpus cavernosum smooth muscle (CCSM) was measured in organ-bath experiments. NOS expression was determined immunohistochemically for neuronal (n)NOS and by Western blot analysis for endothelial (e) and inducible (i) NOS protein. cGMP levels were evaluated by enzyme-linked immunosorbent assay. RESULTS: The erectile response was diminished in the HT group. Nitrergic and endothelium-dependent relaxation was reduced, while the relaxation response to sodium nitroprusside and contractile response to phenylephrine were not altered in CCSM from L-NAME-treated rats. HT rats showed decreased expression of nNOS, whereas eNOS and iNOS protein expression was increased. Sildenafil partly restored endothelial and molecular changes in CCSM from HT rats, but did not reverse the decreased erectile response, even as cGMP levels returned to normal levels. CONCLUSIONS: Sildenafil treatment did not correct the ED in L-NAME-treated HT rats. Under sustained high blood pressure, up-regulation of PDE5 expression failed to reverse the depletion of neuronal NO and/or impaired nNOS activity. However, endothelium-dependent relaxation was restored. Drug targeting of neuronal dysfunction might delay the onset of ED in HT.


Assuntos
Disfunção Erétil/tratamento farmacológico , Hipertensão/complicações , Óxido Nítrico Sintase/metabolismo , Ereção Peniana/efeitos dos fármacos , Inibidores de Fosfodiesterase/uso terapêutico , Piperazinas/uso terapêutico , Sulfonas/uso terapêutico , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Disfunção Erétil/etiologia , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Purinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Citrato de Sildenafila , Regulação para Cima
12.
Prostate ; 69(2): 168-80, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18942118

RESUMO

BACKGROUND: Bone morphogenetic proteins (BMPs) exert osteoinductive effects in prostate cancer (PC) via uncharacterized mechanisms. In this study, we investigated whether the nuclear transcription factor NF-kappaB, implicated in PC metastasis, is involved in transcriptional regulation and activation of BMP-2 or BMP-4/Smad signaling in PC cells. METHODS: NF-kappaB inhibition was achieved by IkappaBalpha super-repressor adenoviral vector and activation was monitored by EMSA and reporter assays. BMP expression and activation was measured by PCR and reporter assays. Promoter binding assay was performed by chromatin immunoprecipitation (ChIP) assay. Smad1/5/8 phosphorylation was measured by Western blot analysis. RESULTS: PCR and chimeric BMP-2 and BMP-4 luciferase assays demonstrate that NF-kappaB confers robust and selective activation of BMP-2 in p65 overexpressing or rhTNF-alpha-stimulated PC cells. Inhibition of NF-kappaB significantly reduced transcript levels and autocrine production of BMP-2 by rhTNF-alpha stimulated C4-2B cells and to a lesser extent by the parental LNCaP cells. Selective inhibition of PI3K/Akt suppressed the NF-kappaB-induced BMP-2 promoter activity. Furthermore, suppression of NF-kappaB activation decreased the transcript levels and BMP-2-induced phosphorylation of Smad1/5/8, critical downstream targets of BMP-2 signaling in PC cells. Notably, the activation of BMPRII by BMP-2 is required for modulation of Smad activation by NF-kappaB in PC cells. Based on ChIP analysis, the transcriptional regulation of BMP-2 gene by NF-kappaB may be partially attributed to binding to kappab site on the BMP-2 promoter. CONCLUSIONS: The data suggest that PI3K/Akt-NF-kappaB axis may promote PC bone metastasis in part by regulating transcription and activation of the BMP-2-Smad signaling cascade in osteotropic PC cells.


Assuntos
Proteína Morfogenética Óssea 2/fisiologia , NF-kappa B/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Smad/fisiologia , Transcrição Gênica , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 4/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Luciferases/genética , Masculino , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Proteínas de Neoplasias/metabolismo , Plasmídeos , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Exp Biol Med (Maywood) ; 234(4): 442-53, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19234050

RESUMO

The highly active anti-retroviral therapy (HAART) regimen has considerably reduced the mortality rate in HIV-1 positive patients. However, long-term exposure to HAART is associated with a metabolic syndrome manifesting cardiovascular dysfunction, lipodystrophy, and insulin resistance syndrome (IRS). The inclusion of HIV-1 protease inhibitors (PIs) in HAART has been linked to the induction of IRS. Although several molecular mechanisms of PI-induced effects on insulin action have been postulated, the deleterious effects of PIs on insulin production by pancreatic beta-cells have not been fully investigated and therapeutic strategies to ameliorate insulin dysregulation at this level have not been targeted. The present study showed that exposure to several different PIs, nelfinavir (5-10 microM), saquinavir (5-10 microM) and atazanavir (8-20 microM), decreases glucose stimulated insulin secretion from rat pancreatic beta-cells (INS-1). Nelfinavir significantly increased reactive oxygen species (ROS) generation and suppressed cytosolic, but not mitochondrial superoxide dismutase (SOD) levels. Nelfinvair also decreased both glutathione and ATP and increased UCP2 levels in these cells. Simultaneous treatment with thymoquinone (TQ) (2.5 microM), an active ingredient of black seed oil, significantly inhibited the effect of nelfinavir on augmented ROS production and suppressed SOD levels. Both TQ and black seed oil exposure increased glucose stimulated insulin secretion and ameliorated the suppressive effect of nelfinavir. The present findings imply a direct role of ROS in PI induced deleterious effects on pancreatic beta-cells. Our findings also suggest that TQ may be used as a potential therapeutic agent to normalize the dysregulated insulin production observed in HAART treated patients.


Assuntos
Benzoquinonas/farmacologia , Glucose/farmacologia , Inibidores da Protease de HIV/toxicidade , Insulina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Sulfato de Atazanavir , Linhagem Celular , Citosol/efeitos dos fármacos , Citosol/enzimologia , Glutationa/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/enzimologia , Células Secretoras de Insulina/metabolismo , Canais Iônicos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Nelfinavir/toxicidade , Nigella sativa/química , Oligopeptídeos/toxicidade , Óleos de Plantas/farmacologia , Piridinas/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , Saquinavir/toxicidade , Sementes/química , Superóxido Dismutase/metabolismo , Proteína Desacopladora 2
14.
Cancer Lett ; 267(1): 116-24, 2008 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-18455293

RESUMO

We have measured the expression of T-type Ca2+ channel mRNA in breast cancer cell lines (MCF-7 (ERalpha+) using Western blot and quantitative real-time PCR (Q-RT-PCR). These results revealed that the MCF-7 cells express both alpha1G and alpha1H isoforms of T-type Ca2+ channels. In order to further clarify the role of T-type Ca2+ channels in proliferation, we tested the effects of a selective T-type Ca2+ channel inhibitor NNC-55-0396 on cellular proliferation. MCF-7 (ERalpha+) cellular proliferation was inhibited by the compound. In contrast, NNC-55-0396 at same concentration had no effect on the proliferation of MCF-10A cells, a non-cancer breast epithelial cell line. We also found that message expression of the T-type Ca2+ channels were only expressed in rapidly growing non-confluent cells but not in the cytostatic confluent cells. Knocking down the expression of T-type Ca2+ channels with siRNA targeting both alpha1G and alpha1H resulted in growth inhibition as much as 45%+/-5.0 in MCF-7 cells as compared to controls. In conclusion, our results suggest that T-type Ca2+ channel antagonism/silencing may reduce cellular proliferation in mitogenic breast cells.


Assuntos
Benzimidazóis/farmacologia , Neoplasias da Mama/metabolismo , Canais de Cálcio Tipo T/metabolismo , Proliferação de Células/efeitos dos fármacos , Mama/efeitos dos fármacos , Mama/metabolismo , Neoplasias da Mama/patologia , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular , Ciclopropanos , Humanos , Naftalenos , RNA Interferente Pequeno/farmacologia
15.
BJU Int ; 102(11): 1651-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18990166

RESUMO

OBJECTIVE: To determine how partial bladder outlet obstruction (PBOO) in a rat model affects erectile function, and whether an uroselective alpha1-adrenoceptor antagonist, alfuzosin (Sanofi-Aventis, Paris, France) attenuates any erectile dysfunction (ED). MATERIALS AND METHODS: Adult male Sprague-Dawley rats (120) were randomized into four groups: 1, sham-operated; 2, alfuzosin-treated; 3, PBOO; and 4, alfuzosin-treated with PBOO. Groups 3 and 4 were subjected to PBOO for 6 weeks by ligation of the urethra, while groups 2 and 4 rats received daily oral alfuzosin (10 mg/day) for 6 weeks. In vivo erectile responses were monitored by evaluating ratios of intracavernosal pressure (ICP)/mean arterial pressure, and total ICP (area under the curve). Organ-bath studies were performed on corpus cavernosum smooth muscle (CCSM) strips. Nitric oxide synthase (NOS) expression was determined immunohistochemically (IHC) for neuronal (n)NOS and by Western blot analysis for endothelial (e) and inducible (i) NOS protein. RESULTS: Rats with PBOO showed lower erectile responses than controls. Maximum electrical field stimulation-mediated and endothelium-dependent acetylcholine-induced relaxations and contractile responses to phenylephrine were significantly reduced in CCSM strips from the PBOO group. The NO donor sodium nitroprusside completely relaxed CCSM from rats in all groups. IHC analyses showed decreased expression of nNOS in PBOO groups compared with controls; by contrast, protein expression of eNOS and iNOS was increased. Alfuzosin-treatment partially attenuated functional and molecular changes in penises of PBOO rats. CONCLUSION: Rats with PBOO show ED, most likely due to altered NOS expression and NO bioavailability. The alpha-adrenoreceptor antagonist alfuzosin reversed this ED by altering sympathetic tone, increasing NO-induced relaxation and augmenting blood flow in the penis. This study suggests a rationale for further clinical trials using combinations of alpha-adrenoceptor antagonists and phosphodiesterase-5 inhibitors in patients with ED and lower urinary tract symptoms.


Assuntos
Antagonistas Adrenérgicos alfa/uso terapêutico , Disfunção Erétil/tratamento farmacológico , Quinazolinas/uso terapêutico , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Animais , Western Blotting , Disfunção Erétil/etiologia , Disfunção Erétil/fisiopatologia , Imuno-Histoquímica , Masculino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Ereção Peniana/efeitos dos fármacos , Pênis/irrigação sanguínea , Pênis/efeitos dos fármacos , Pênis/fisiopatologia , Ratos , Ratos Sprague-Dawley , Obstrução do Colo da Bexiga Urinária/complicações
16.
Int J Radiat Biol ; 84(11): 900-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19016138

RESUMO

PURPOSE: N-(2-mercaptoethyl)1,3-diaminopropane (WR-1065), is the active metabolite of amifostine, a broad spectrum cytoprotective agent used in conjunction with both chemo- and radiotherapy of certain cancers. This report describes for the first time an oral formulation of WR-1065 and follows on from our earlier report of a similar oral formulation of amifostine. MATERIALS AND METHODS: The nanoparticles of WR-1065 were prepared by spray drying technique using poly lactide-co-glycolide (PLGA) as the polymer matrix. Radioprotection was determined by measuring reductions in radiation-induced: (i) 30-day survival; (ii) bone marrow suppression; and (iii) intestinal injury following 9 Gray (Gy) whole body gamma irradiation in mice. All treatments were given 1 hour pre-irradiation and WR-1065 was tested at the dose of 500 mg/kg. RESULTS: The WR-1065/PLGA nanoparticles were smooth and spherical with the average diameter of 206 nm and contained 21.7% (w/w) WR-1065. While irradiation markedly reduced 30-day survival in non-treated control mice, and caused significant bone marrow suppression and intestinal injury in surviving mice, oral administration of WR-1065/PLGA nanoparticles resulted in significant radioprotection as evidenced by a marked reduction in all three of the above mentioned parameters of radiation injury. CONCLUSIONS: These findings clearly demonstrate the feasibility of developing an effective oral formulation of WR-1065 as a radioprotective agent.


Assuntos
Mercaptoetilaminas/administração & dosagem , Mercaptoetilaminas/farmacologia , Nanopartículas/química , Poliglactina 910/química , Protetores contra Radiação/administração & dosagem , Protetores contra Radiação/farmacologia , Administração Oral , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Jejuno/citologia , Jejuno/efeitos dos fármacos , Jejuno/efeitos da radiação , Masculino , Mercaptoetilaminas/química , Camundongos , Protetores contra Radiação/química , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/efeitos da radiação , Taxa de Sobrevida
17.
Int Med Case Rep J ; 11: 125-127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29872353

RESUMO

BACKGROUND: Drug-induced hypersensitivity reaction is of great clinical significance in therapeutics. The objective of this reporting of two cases is to show that anaphylaxis reaction can occur with pantoprazole. CASE SUMMARIES: A 38-year-old female reported to the emergency ward in a critical condition, with a history of periorbital edema, edema of the skin, pruritus, nausea, vomiting, and difficulty breathing 20 minutes after ingestion of a pantoprazole 40 mg tablet. A 32-year-old female reported to the emergency ward in a critical condition, with complaints of rashes all over the body, itching on the whole body, and swollen lips and eyes after ingestion of a pantoprazole 40 mg tablet. CONCLUSION: It is necessary for all health care providers to know that pantoprazole can cause anaphylaxis, which is a life-threatening reaction, and to be cautious while prescribing it.

19.
Cancer Res ; 65(21): 9891-8, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16267013

RESUMO

The chemokine stromal-derived factor-1alpha (SDF-1alpha/CXCL-12) and its receptor, CXCR4, play a crucial role in adhesion and transendothelium migration (TEM) of prostate cancer cells. We tested the hypothesis that enhanced expression of CXCR4 in prostate cancer cells is dependent upon SDF-1alpha-mediated activation of nuclear factor-kappaB (NF-kappaB). SDF-1alpha increased the CXCR4 mRNA and protein expression in PC-3 cells but not in LNCaP cells. Similarly, SDF-1alpha enhanced the NF-kappaB-dependent transcriptional activity in PC-3 cells but not in LNCaP cells. SDF-1alpha increased PC-3 cell adhesion to the human umbilical vein endothelial cell monolayer and enhanced TEM, which was abrogated with anti-CXCR4 monoclonal antibody (mAb). Suppression of NF-kappaB activity in PC-3 cells by a mutant IkappaBalpha super-repressor adenoviral vector decreased the CXCR4 mRNA expression and inhibited adhesion and TEM. Transient overexpression of p65 subunit of NF-kappaB in PC-3 cells up-regulated CXCR4 receptor expression and increased the adhesion and TEM of these cells in response to SDF-1alpha gradient. Treatment of PC-3 cells with SDF-1alpha leads to nuclear translocation of NF-kappaB protein within 15 to 30 minutes, which correlated with IkappaBalpha phosphorylation. A p42/44 mitogen-activated protein kinase [MAPK, extracellular signal regulated kinase-1/2 (ERK-1/2)] biphasic activation pattern was observed in these cells at 15 minutes and 3 hours after SDF-1alpha treatment. Phosphorylation of IkappaB kinase alpha was observed within 30 minutes, which was blocked by PD98059 [MAPK kinase (MEK) inhibitor]. PD98059 cotreatment significantly inhibited SDF-1alpha-induced NF-kappaB reporter activity and CXCR4 receptor expression as shown by flow cytometry. These data suggest that SDF-1alpha-induced expression of CXCR4 in PC-3 cells is dependent on MEK/ERK signaling cascade and NF-kappaB activation.


Assuntos
Quimiocinas CXC/farmacologia , Células Endoteliais/citologia , Sistema de Sinalização das MAP Quinases/fisiologia , NF-kappa B/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores CXCR4/biossíntese , Neoplasias Ósseas/secundário , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Quimiocina CXCL12 , Quimiocinas CXC/metabolismo , Células Endoteliais/metabolismo , Humanos , Proteínas I-kappa B/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , NF-kappa B/antagonistas & inibidores , Fosforilação , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Receptores CXCR4/genética , Proteínas Recombinantes/farmacologia , Fator de Transcrição RelA/biossíntese , Fator de Transcrição RelA/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Indian J Endocrinol Metab ; 21(5): 719-723, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28989881

RESUMO

OBJECTIVES: The objective of the study was to assess the differences of iodine status as measured by urinary iodine excretion (UIE) between cases of hypothyroidism and healthy controls. MATERIALS AND METHODS: The study was conducted in cases with subclinical hypothyroidism (n = 58) and overt hypothyroidism (n = 41) and compared with age- and sex-matched healthy euthyroid controls (n = 52) attending Universal College of Medical Sciences Teaching Hospital, Bhairahawa, Nepal. Serum free triiodothyronine (fT3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH) were estimated by competitive ELISA and sandwich ELISA, respectively (Diametra, Italy). The urinary iodine concentration (UIC) in urine samples was estimated by ammonium persulfate digestion method recommended by the WHO. RESULTS: A significantly higher median UIC was observed among cases of subclinical hypothyroidism (224.90 µg/l) and overt hypothyroidism (281.0 µg/l) as compared to the controls (189.90 µg/l) (P = 0.0001, P = 0.001). Serum TSH in the cases of subclinical hypothyroid was higher, whereas fT3 was lower as compared to controls (P = 0.028, P = 0.0001), respectively. Similarly, serum TSH in the cases of overt hypothyroid was higher and fT3 and fT4 were lower as compared to controls (P = 0.0001, P = 0.0001, P = 0.015), respectively. There was positive correlation of UIC with TSH (r = 0.269, P = 0.0001), whereas negative correlation was seen with fT3 (r = -0.328, P = 0.0001) and fT4 (r = -0.145, P = 0.076). The test of multiple regression has shown that fT3 (ß = -0.262, P = 0.012) as an independent predictor in association with UIE in cases. CONCLUSION: Excessive iodine intake was found in hypothyroid patients as assessed by UIE concluding that it may trigger the thyroid hypofunction. Cohort studies to generate further evidence should be done to explore potential mechanism of hypothyroidism in excess iodine intake.

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