Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Glia ; 71(3): 485-508, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36380708

RESUMO

A major hallmark of neuroinflammation is the activation of microglia and astrocytes with the induction of inflammatory mediators such as IL-1ß, TNF-α, iNOS, and IL-6. Neuroinflammation contributes to disease progression in a plethora of neurological disorders ranging from acute CNS trauma to chronic neurodegenerative disease. Posttranscriptional pathways of mRNA stability and translational efficiency are major drivers for the expression of these inflammatory mediators. A common element in this level of regulation centers around the adenine- and uridine-rich element (ARE) which is present in the 3' untranslated region (UTR) of the mRNAs encoding these inflammatory mediators. (ARE)-binding proteins (AUBPs) such as Human antigen R (HuR), Tristetraprolin (TTP) and KH- type splicing regulatory protein (KSRP) are key nodes for directing these posttranscriptional pathways and either promote (HuR) or suppress (TTP and KSRP) glial production of inflammatory mediators. This review will discuss basic concepts of ARE-mediated RNA regulation and its impact on glial-driven neuroinflammatory diseases. We will discuss strategies to target this novel level of gene regulation for therapeutic effect and review exciting preliminary studies that underscore its potential for treating neurological disorders.


Assuntos
Doenças do Sistema Nervoso Central , Doenças Neurodegenerativas , Humanos , RNA/metabolismo , Doenças Neuroinflamatórias , Doenças Neurodegenerativas/metabolismo , Astrócitos/metabolismo , Doenças do Sistema Nervoso Central/genética , Doenças do Sistema Nervoso Central/terapia , Doenças do Sistema Nervoso Central/metabolismo , Mediadores da Inflamação/metabolismo
2.
BMC Cancer ; 23(1): 875, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723439

RESUMO

BACKGROUND: Vietnam and Saudi Arabia have high disease burden of primary hepatocellular carcinoma (HCC). Early detection in asymptomatic patients at risk for HCC is a strategy to improve survival outcomes in HCC management. GALAD score, a serum-based panel, has demonstrated promising clinical utility in HCC management. However, in order to ascertain its potential role in the surveillance of the early detection of HCC, GALAD needs to be validated prospectively for clinical surveillance of HCC (i.e., phase IV biomarker validation study). Thus, we propose to conduct a phase IV biomarker validation study to prospectively survey a cohort of patients with advanced fibrosis or compensated cirrhosis, irrespective of etiologies, using semi-annual abdominal ultrasound and GALAD score for five years. METHODS: We plan to recruit a cohort of 1,600 patients, male or female, with advanced fibrosis or cirrhosis (i.e., F3 or F4) and MELD ≤ 15, in Vietnam and Saudi Arabia (n = 800 each). Individuals with a liver mass ≥ 1 cm in diameter, elevated alpha-fetoprotein (AFP) (≥ 9 ng/mL), and/or elevated GALAD score (≥ -0.63) will be scanned with dynamic contrast-enhanced magnetic resonance imaging (MRI), and a diagnosis of HCC will be made by Liver Imaging Reporting and Data System (LiRADS) assessment (LiRADS-5). Additionally, those who do not exhibit abnormal imaging findings, elevated AFP titer, and/or elevated GALAD score will obtain a dynamic contrast-enhanced MRI annually for five years to assess for HCC. Only MRI nearest to the time of GALAD score measurement, ultrasound and/or AFP evaluation will be included in the diagnostic validation analysis. MRI will be replaced with an abdominal computed tomography scan when MRI results are poor due to patient conditions such as movement etc. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced MRI will not be carried out in study sites in both countries. Bootstrap resampling technique will be used to account for repeated measures to estimate standard errors and confidence intervals. Additionally, we will use the Cox proportional hazards regression model with covariates tailored to the hypothesis under investigation for time-to-HCC data as predicted by time-varying biomarker data. DISCUSSION: The present work will evaluate the performance of GALAD score in early detection of liver cancer. Furthermore, by leveraging the prospective cohort, we will establish a biorepository of longitudinally collected biospecimens from patients with advanced fibrosis or cirrhosis to be used as a reference set for future research in early detection of HCC in the two countries. TRIAL REGISTRATION: Name of the registry: ClinicalTrials.gov Registration date: 22 April 2022 Trial registration number: NCT05342350 URL of trial registry record.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Feminino , Masculino , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Estudos Prospectivos , alfa-Fetoproteínas , Cirrose Hepática/complicações
3.
Clin Transplant ; 37(6): e14983, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37026809

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and the resulting disease, coronavirus disease 2019 (COVID-19), have spread to millions of persons worldwide. Many vaccines have been developed; however, their efficacy in pediatric solid organ transplant recipients is yet to be determined. METHODS: This is a prospective observational, non-interventional single-center study on the safety and efficacy of a COVID-19 vaccine (BNT162b2) in pediatric kidney transplant recipients. The primary aim of this study was to evaluate immunogenicity according to SARS-CoV-2-specific neutralizing antibody titer after two vaccine doses. The secondary aims were to investigate the safety of the vaccines, solicited local and systemic adverse reactions, incidence of COVID-19 post-vaccination, and effects on transplant graft function. Baseline investigations were conducted on pediatric renal transplant recipients, and recruited participants were advised to have the Comirnaty® mRNA vaccine according to protocol. RESULTS: A total of 48 patients (male, n = 31, 64.6%; female, n = 17, 35.4%), median age 14 [12-16] years were included, and all received two doses of the vaccine. The vaccine had a favorable safety and side-effect profile. The S-antibody titer of all patients ranged between .4 and 2,500 U/ml and was > 50 U/ml in 89% of the patients. No difference in the measured antibody immune response was noted between infected and uninfected children. No major side effects were reported. CONCLUSION: The vaccine had a favorable safety profile in 12- to 15-year-old kidney transplant recipients, producing a greater measured antibody response than that in older transplant recipients.


Assuntos
COVID-19 , Transplante de Rim , Adolescente , Criança , Feminino , Humanos , Masculino , Anticorpos Antivirais , Vacina BNT162/efeitos adversos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , SARS-CoV-2 , Transplantados
4.
BMC Public Health ; 23(1): 789, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118706

RESUMO

BACKGROUND: Diabetes and arterial hypertension are the two most common types of non-communicable diseases (NCDs) impacting people globally. There is no prior research on the Syrian population's knowledge and treatment of hypertension and diabetes. It is crucial to investigate how the Syrian public understands and perceives these disorders in order to address the increased incidence and prevalence of hypertension and diabetes. This research intends to assess the level of hypertension and diabetes-related awareness, knowledge, attitude, and practices among Syrian individuals. METHODS: A cross-sectional survey was conducted online between 1 August and 25 August 2022. The questionnaire for the study was developed based on previous research, and the inclusion criteria for the sample were Syrian residents older than 18 who presently live in Syria. The survey consisted four sections: sociodemographics information, WHO STEPS survey instrument on knowledge of and lifestyle determinants for hypertension and diabetes, respondents' knowledge of and comprehension of hypertension and diabetes, and respondents' awareness of these disorders. RESULTS: Among 976 participants, 65.8% were females. the most common causes for hypertension from the perspective of participants were (90.1%) for stress, (87%) High salt consumption, (82.1%) genetics, (78.2%) old age, (78%) obesity (69%) anxiety, and (38.6%) for drug usage. Primary and middle school educational status participants had greater hypertension knowledge (92.3%) than other educational levels. There was a statistical significant difference between the knowledge toward the hypertension and the drinking alcohol, which the nonalcoholic knowledgeable persons were the most common (819 / 976)(P < 0.05). Participants whose lifestyles did not include alcohol use had a higher hypertension knowledge level (90.3%). Participants who do not consume alcohol have shown better hypertension knowledge (90.3%) than those who do (81.9%). Almost age groups have shown good knowledge of diabetes, especially participants aged above 55 (93.8%). However, most individuals have examined blood pressure (82.3%), whereas fewer than half had screened for blood sugar (64.4%). About 82.2% of individuals check their blood pressure frequently, whereas 6.2% monitor their blood sugar. There were significant associations between hypertension knowledge and gender, education, employment, and economic position (P value < 0.05). Men (mean = 8.39, SD = 2.02, P-value < 0.05) have a higher hypertension knowledge than females, and knowledge of hypertension among participants was shown to be higher among those in good income status than other economic levels (mean = 8.34, SD = 1.98). Age, gender, education, employment, and marital status were all associated with diabetes knowledge. Participants between the ages of 40 and 55 showed better knowledge of diabetes compared to other age groups (mean = 11.32, SD = 2.54); also, men demonstrated greater knowledge of diabetes than females (mean = 10.76, SD = 2.79). CONCLUSION: We indicated that the Syrian population has a good to moderate understanding of hypertension and diabetes. However, there is still a shortage of standardized, regular screening practices. Since individuals remain involved in unhealthy lifestyle habits, it is vital to provide accurate information about hypertension and diabetes to encourage them to make healthy changes.


Assuntos
Diabetes Mellitus , Hipertensão , Masculino , Feminino , Humanos , Idoso , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Síria/epidemiologia , Glicemia , Hipertensão/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Prevalência
5.
Heart Fail Rev ; 27(5): 1579-1586, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35048207

RESUMO

Literature regarding recent trends, mortality outcomes of ST-elevation myocardial infarction (STEMI) in cardiac amyloidosis (CA) patients is limited.To study coronary interventions, and trends in prevalence and mortality outcomes among CA patients with STEMI.Data from the national readmissions database (NRD) sample that constitutes 49.1% of the stratified sample of all hospitals in the USA, representing more than 95% of the national population, were analyzed for hospitalizations associated with CA with STEMI. A linear p-trend was used to assess the trends.Out of the total 4252 adult patients (mean age 73.3 ± 11.7 years, 40.2% females) with diagnosis of CA, 439 (10.3%) had STEMI while 3813 (89.7%) had no STEMI. STEMI-CA patients had higher rates of multi-organ manifestations including VT/VF (12% vs 8.5%; p-value < 0.001), cardiogenic shock (12.7% vs 7.3%; p < 0.001), AKI requiring dialysis (5.3% vs 4%; p < 0.001), and ICU admissions (25.2% vs 15.3%; p < 0.001) compared to CA without STEMI. CA-STEMI had increased mortality rates (23.7% vs 16.1%, p < 0.001) compared to CA without STEMI. On multivariate logistic regression analysis, coronary interventions including PCI (OR 0.6, CI 0.4-1.1; p = 0.3) and CABG (OR 0.7, CI 0.3-1.8; p = 0.2) had no association with mortality among CA patients. The absolute yearly trends for prevalence and mortality associated with STEMI in CA patients remained steady over the study years (linear p-trends 0.2 and 0.6, respectively).CA-STEMI is associated with significant complications and mortality. Coronary interventions may not have significant mortality benefits. Thus, more research will be needed to improve mortality rates among these patients.


Assuntos
Amiloidose , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Fatores de Tempo , Resultado do Tratamento
6.
J Emerg Med ; 62(3): 306-315, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35058097

RESUMO

BACKGROUND: Literature regarding trends in incidence and mortality of ST-elevation myocardial infarction (STEMI) in emergency departments (EDs) is limited. OBJECTIVE: To study the trends of incidence and mortality of STEMI. METHODS: Using the National Emergency Department Sample database in the United States, we identified all ED encounters for patients presenting with STEMI using International Classification of Diseases codes. A linear p-trend was used to assess the trends. RESULTS: Out of the 973 million ED encounters represented, 641,762 (65/100,000; mean age 69 [59-81] years, 35.8% female) adult patients were recorded with STEMI. Among the major complications associated with STEMI, a total of 49,401 (7.7%) had cardiac complications, which included acute heart failure (n = 9361, 1.6%), ventricular tachycardia or fibrillation (n = 12,267, 1.91%), conduction block (n = 20,165, 3.1%), and cardiogenic shock (n = 7608, 1.2%). There were 5675 (0.9%) patients recorded with cerebrovascular events, which included acute ischemic stroke among 5205 (0.8%) patients and 470 (0.1%) with transient ischemic attack. Acute kidney injury was recorded for 10,082 (1.6%) patients. The trend for incidence of STEMI in the ED had decreased from 7.76/10,000 in 2011 to 4.07/10,000 in 2018 (linear p-trend 0.0006). However, the yearly mortality of STEMI related to ED encounters had remained relatively steady: 7.56% in 2011 to 7.50% in 2018 (linear p-trend 0.2364). CONCLUSION: Despite the fact that the number of patients presenting to the ED with STEMI has been decreasing, the mortality trends have remained steady. Further research of in-hospital STEMI may yield opportunities to reduce the risk of complications, improve patient outcomes and decrease health care burden.


Assuntos
AVC Isquêmico , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Adulto , Idoso , Estudos de Coortes , Serviço Hospitalar de Emergência , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Choque Cardiogênico , Estados Unidos/epidemiologia
7.
COPD ; 18(5): 567-575, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34530662

RESUMO

Literature regarding trends of incidence, mortality, and complications of acute exacerbation of chronic obstructive pulmonary disease (COPD) in the emergency departments (ED) is limited. What are trends of COPD exacerbation in ED? Data were obtained from the Nationwide Emergency Department Sample (NEDS) that constitutes a 20% sample of hospital-owned EDs and inpatient sample in the US. All ED encounters were included in the analysis. Complications of AECOPD were obtained by using ICD codes. Out of 1.082 billion ED encounters, 5,295,408 (mean age 63.31 ± 12.63 years, females 55%) presented with COPD exacerbation. Among these patients, 353,563(6.7%) had AECOPD-plus (features of pulmonary embolism, acute heart failure and/or pneumonia) while 4,941,845 (93.3%) had exacerbation without associated features or precipitating factors which we grouped as AECOPD. The AECOPD-plus group was associated with statistically significantly higher proportion of cardiovascular complications including AF (5.6% vs 3.5%; p < 0.001), VT/VF (0.14% vs 0.06%; p < 0.001), STEMI (0.22% vs 0.11%; p < 0.001) and NSTEMI (0.65% vs 0.2%; p < 0.001). The in-hospital mortality rates were greater in the AECOPD-plus population (0.7% vs 0.1%; p < 0.001). The incidence of both AECOPD and AECOPD-plus had worsened (p-trend 0.004 and 0.0003) and the trend of mortality had improved (p-trend 0.0055 and 0.003, respectively). The prevalence of smoking for among all COPD patients had increased (p-value 0.004), however, the prevalence trend of smoking among AECOPD groups was static over the years 2010-2018. There was an increasing trend of COPD exacerbation in conjunction with smoking; however, mortality trends improved significantly. Moreover, the rising burden of AECOPD would suggest improvement in diagnostics and policy making regarding management.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Doença Aguda , Idoso , Progressão da Doença , Serviço Hospitalar de Emergência , Feminino , Mortalidade Hospitalar , Humanos , Incidência , Classificação Internacional de Doenças , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Estados Unidos/epidemiologia
8.
Eur Arch Otorhinolaryngol ; 277(1): 121-128, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31552526

RESUMO

PURPOSE: Allergic fungal rhinosinusitis (AFRS) is a common disorder with a high prevalence and a very high incidence of recurrence. Management includes surgery and medical treatment in the form of local and/or systemic steroids. However, some cases are resistant to the action of steroids and further treatment is warranted. Being an immune-mediated disorder, targeting IgE seems a logical step. Immunotherapy drugs acting on the IgE (e.g. omalizumab) can modify the clinical course of the disease. This study aimed at evaluating the effect of omalizumab on the clinical course of patients undergoing surgery for AFRS. MATERIALS AND METHODS: This is a two-arm prospective, randomized, single blind clinical trial among patients with AFRS. Twenty patients were included and randomly divided into two groups: Group A; 10 patients received a single subcutaneous injection of omalizumab (Xolair ' Novartis) (150 mg) 2 weeks postoperatively. Group B: 10 patients received local steroids nasal sprays (budesonide or mometasone furoate, 100 µg twice daily for 6 months, starting 2 weeks postoperatively. All patients underwent history, examination, CT scan and IgE level estimation and were submitted to endoscopic sinus surgery. They were evaluated at 4 weeks interval for 6 months. RESULTS: In both groups there were highly significant differences between pre/post-operative SNOT-20 scores, TNSS scores, total IgE level and Philpott-Javer staging scores. Comparison between the two study groups at 24 weeks showed a highly significant difference (p = 0.001) between post-operative SNOT 20 and TNSS scores in favour of group A. There was no statistically significant difference between the two study groups as regarding postoperative total IgE or Philpott-Javer scores. There were two recurrences in both arms, but no significant side effects. DISCUSSION: We compared a single post operative injection of omalizumab with twice daily intranasal steroid spray for 6 months. Both treatments were effective, but the omalizumab group showed a more significant clinical and endoscopic response. There were no significant side effects in both arms. This novel approach used a single low dose injection of omalizumab increased the compliance of the patients with minimal complications. Longer follow-up of the patients is ongoing to determine the optimal time for re-injection. The only downside was the higher cost of omalizumab compared to that of local steroids.


Assuntos
Glucocorticoides/administração & dosagem , Micoses/tratamento farmacológico , Omalizumab/administração & dosagem , Rinite Alérgica/tratamento farmacológico , Sinusite/tratamento farmacológico , Administração Intranasal , Adolescente , Adulto , Antialérgicos/administração & dosagem , Antialérgicos/uso terapêutico , Budesonida/administração & dosagem , Budesonida/imunologia , Budesonida/uso terapêutico , Doença Crônica , Endoscopia , Feminino , Glucocorticoides/uso terapêutico , Indicadores Básicos de Saúde , Humanos , Imunoglobulina E/imunologia , Injeções Subcutâneas , Masculino , Furoato de Mometasona/administração & dosagem , Furoato de Mometasona/uso terapêutico , Micoses/imunologia , Micoses/microbiologia , Micoses/cirurgia , Pólipos Nasais/tratamento farmacológico , Pólipos Nasais/imunologia , Pólipos Nasais/cirurgia , Sprays Nasais , Omalizumab/uso terapêutico , Estudos Prospectivos , Rinite Alérgica/imunologia , Rinite Alérgica/microbiologia , Rinite Alérgica/cirurgia , Método Simples-Cego , Sinusite/imunologia , Sinusite/microbiologia , Sinusite/cirurgia , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Mol Biol Rep ; 45(5): 699-711, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29948634

RESUMO

MYD88 is an adaptor protein known to involve in activation of NF-κB through IL-1 receptor and TLR stimulation. It consists of N-terminal death domain and C-terminal Toll/IL-R homology domain that mediates its interaction with IL-1R associated kinase and IL-1R/TLR, respectively. MYD88 contributes to various types of carcinogenesis due to its involvement in oncogene induced inflammation. In the present study, we have recognized two new alternatively spliced variants of MyD88 gene in mouse using bioinformatics tools and molecular biology techniques in combination. The newly identified non-coding exon (NE-1) from 5' upstream region alternatively splices with either exon E-2 or exon E-5 to produce two novel transcript variants MyD88N1 and MyD88N2 respectively. The transcript variant MyD88N1 was expressed in several tissues studied while the variant MyD88N2 was found to be expressed only in the brain. The analysis of the upstream region of novel exon by in silico approach revealed new promoter region PN, which possess potential signature sequences for diverse transcription factors, suggesting complex gene regulation. Studies of post translational modifications of conceptualized amino acid sequences of these isoforms revealed diversity in properties. Western blot analysis further confirmed the expression of protein isoform MYD88N1.


Assuntos
Processamento Alternativo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Neoplasias/genética , Animais , Encéfalo/metabolismo , Simulação por Computador , Domínio de Morte , Éxons , Regulação da Expressão Gênica , Humanos , Camundongos , Fator 88 de Diferenciação Mieloide/química , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Distribuição Tecidual , Fatores de Transcrição
10.
IUBMB Life ; 69(2): 106-114, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28111880

RESUMO

Nur77 is a member of nuclear receptor superfamily that acts as a transcription factor and regulates expression of multiple genes. Subcellular localization of Nur77 protein plays an important role in the survival and cell death. In this study, we have predicted and confirmed alternatively spliced two new transcripts of Nur77 gene in mouse. The newly identified transcripts have their alternatively spliced first exon located upstream of published 5'-UTR of the gene. Transcription factor binding sites in the possible promoter regions of these transcripts were also analyzed. Expression of novel transcript variants was found to be significantly lower than the already published transcript. New transcript variants encode for NUR77 protein isoforms which are significantly smaller in size due to lack of transactivation domain and a part of DNA binding domain. Western blot analysis using NUR77 specific antibody confirmed the existence of these smaller variants in mouse. Localization of these new isoforms was predicted to be majorly outside the nucleus. In silico analysis of the conceptually translated proteins was performed using different bioinformatics tools. The results obtained in this study offer further insight into novel area of research on extensively studied Nur77. © 2017 IUBMB Life, 69(2):106-114, 2017.


Assuntos
Núcleo Celular/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Processamento Alternativo/genética , Animais , Éxons/genética , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , Domínios Proteicos/genética
11.
Arch Biochem Biophys ; 625-626: 1-12, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28558964

RESUMO

Pirenzepine is an anti-ulcer agent which belongs to the anti-cholinergic group of gastrointestinal disorder drugs and functions as an M1 receptor selective antagonist. Drug-DNA interaction studies are of great significance as it helps in the development of new therapeutic drugs. It provides a deeper understanding into the mechanism through which therapeutic drugs control gene expression. Interaction of pirenzepine with calf-thymus DNA (Ct-DNA) was determined via a series of biophysical techniques. UV-visible absorption and fluorescence spectroscopy confirmed the formation of pirenzepine-Ct-DNA complex. The values of binding constant from various experiments were calculated to be in the order of 103 M-1 which is consistent with the groove binding mode. Various spectrofluorimetric experiments like competitive displacement of well known dyes with drug, iodide quenching experiments and the effect of Ct-DNA denaturation in presence of drug confirmed the binding of pirenzepine to the groove of Ct-DNA. The binding mode was further established by viscometric, circular dichroic and molecular modelling studies. Thermodynamic parameters obtained from isothermal titration calorimetric studies suggest that the interaction of pirenzepine with Ct-DNA is enthalpically driven. The value of TΔS and ΔH calculated from calorimetric studies were found to be 4.3 kcal mol-1 and -2.54 kcal mol-1 respectively, indicating that pirenzepine-Ct-DNA complex is mainly stabilized by hydrophobic interaction and hydrogen bonding. The binding energy calculated was -7.5 kcal mol-1 from modelling studies which was approximately similar to that obtained by isothermal titration calorimetric studies. Moreover, the role of electrostatic interaction in the binding of pirenzepine to Ct-DNA cannot be precluded.


Assuntos
DNA/metabolismo , Fármacos Gastrointestinais/metabolismo , Pirenzepina/metabolismo , Animais , Calorimetria , Bovinos , DNA/química , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico/efeitos dos fármacos , Desnaturação de Ácido Nucleico/efeitos dos fármacos , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
12.
IUBMB Life ; 68(2): 122-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26707719

RESUMO

The aryl hydrocarbon receptor nuclear translocator (ARNT/HIF1-ß) is an obligatory transcriptional partner of the aryl hydrocarbon receptor (AHR) and hypoxia-inducible factor-1α (HIF-1α). It has a basic helix-loop-helix domain that belongs to period-ARNT-single-minded (PAS) protein family. PAS proteins act as heterodimeric transcription factors with ARNT being master dimerization partner. The ARNT-HIF-1α complex is an important transcriptional regulator of the hypoxic response of the tumor cells. Previous studies have reported two transcript variants of the gene produced by alternative splicing in mouse. One transcript variant contains all 22 exons while the other variant lacks exon-E5. In our study, using combinatorial approach comprising bioinformatics tools and molecular biology techniques involving RT-PCR, semi-nested PCR, sequencing and qPCR, we have identified three novel transcript variants of Arnt gene in mouse. All three new transcripts arise as a result of alternative splicing of newly identified exons with exon-E2, replacing reported exon-E1. These transcripts encode for three protein isofoms having different N-termini. The expression of these transcripts was found to be different in different tissues of adult mice. In silico analysis of the upstream region of the new exons revealed three distinct promoter regions designated as PA, PB and PC present upstream of newly identified exons. These promoters possess potential signature sequences for common as well as different transcription factors suggesting complex regulation of Arnt gene. In silico post translational studies of the conceptually translated amino acid sequences of these transcripts show similarity in some of the properties while differ in others. The diversity at N-termini of protein isoforms suggests the possibility of forming different complexes in different tissues and may also be important for unique interactions with partner molecules.


Assuntos
Processamento Alternativo/genética , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Isoformas de Proteínas/genética , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/biossíntese , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Hipóxia Celular/genética , Éxons , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Regiões Promotoras Genéticas , Isoformas de Proteínas/biossíntese
13.
Oncologist ; 20(7): 737-41, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26054632

RESUMO

BACKGROUND: Cixutumumab (a humanized monoclonal antibody against insulin-like growth factor-1 receptor [IGF-1R]) and the mammalian target of rapamycin (mTOR) inhibitor temsirolimus were combined in a phase I study of patients with advanced cancer. We investigated the prevalence of metabolic toxicities, their management, and impact on outcome. METHODS: The temsirolimus dose was 25 mg or 37.5 mg i.v. weekly with escalating doses of cixutumumab (3, 5, or 6 mg/kg i.v. weekly). No patients with diabetes or hyperlipidemia at baseline were eligible until the expansion cohort. We assessed metabolic derangements in our patient cohort, their management, and their association with tumor shrinkage, time to progression (TTP) and overall survival (OS). RESULTS: Of the 57 patients analyzed, hyperglycemia was seen in 36 (63%) (grade 1-2: 33 [58%]; grade 3-4: 3 [5%]). The median blood sugar level (fasting and nonfasting) across cohorts was 149 mg/dL (upper limit of normal: 110 mg/dL). No patient developed diabetic ketoacidosis or nonketotic hyperosmolar coma or pancreatitis during treatment. Median maximum triglyceride, cholesterol, and low-density lipoprotein levels achieved were 247 mg/dL (range: 65-702 mg/dL), 243 mg/dL (range: 103-424 mg/dL), and 153 mg/dL (range 50-375 mg/dL), respectively. Higher glucose levels were associated with more RECIST tumor shrinkage (r = -.30 [95% confidence interval: -.52, -.03; p = .03]). There was no association between metabolic toxicities of the mTOR and IGF-1R combination and TTP or OS. CONCLUSION: The combination of temsirolimus and cixutumumab was safe and resulted in manageable metabolic toxicities. More tumor shrinkage was seen in patients who developed these adverse events. Although perhaps limited by the small number of patients, no significant association was discerned between hyperglycemia, hypertriglyceridemia, or hypercholesterolemia and TTP or OS. IMPLICATIONS FOR PRACTICE: Results of this study show that the combination of temsirolimus and cixutumumab is safe. The most common side effects, hyperglycemia and hyperlipidemia, are tolerable and manageable. This combination of therapies should not be withheld from diabetic patients and patients with high cholesterol levels. Collaboration between oncologist and endocrinologist allows for individualized treatment and better control of these adverse events, with few dose interruptions and reductions. Supportive care and close monitoring is needed. Those patients who develop hyperglycemia or hypercholesterolemia may benefit more from the drug.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hiperglicemia/induzido quimicamente , Hiperlipidemias/induzido quimicamente , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Feminino , Humanos , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/epidemiologia , Hiperglicemia/tratamento farmacológico , Hiperglicemia/epidemiologia , Hiperlipidemias/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/metabolismo , Neoplasias/patologia , Receptor IGF Tipo 1/imunologia , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/análogos & derivados , Análise de Sobrevida , Serina-Treonina Quinases TOR/antagonistas & inibidores , Resultado do Tratamento , Adulto Jovem
14.
Toxicol Appl Pharmacol ; 289(2): 251-61, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26415834

RESUMO

Ferulic acid (FA) is a plant polyphenol showing diverse therapeutic effects against cancer, diabetes, cardiovascular and neurodegenerative diseases. FA is a known antioxidant at lower concentrations, however at higher concentrations or in the presence of metal ions such as copper, it may act as a pro-oxidant. It has been reported that copper levels are significantly raised in different malignancies. Cancer cells are under increased oxidative stress as compared to normal cells. Certain therapeutic substances like polyphenols can further increase this oxidative stress and kill cancer cells without affecting the proliferation of normal cells. Through various in vitro experiments we have shown that the pro-oxidant properties of FA are enhanced in the presence of copper. Comet assay demonstrated the ability of FA to cause oxidative DNA breakage in human peripheral lymphocytes which was ameliorated by specific copper-chelating agent such as neocuproine and scavengers of ROS. This suggested the mobilization of endogenous copper in ROS generation and consequent DNA damage. These results were further validated through cytotoxicity experiments involving different cell lines. Thus, we conclude that such a pro-oxidant mechanism involving endogenous copper better explains the anticancer activities of FA. This would be an alternate non-enzymatic, and copper-mediated pathway for the cytotoxic activities of FA where it can selectively target cancer cells with elevated levels of copper and ROS.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cobre/metabolismo , Ácidos Cumáricos/farmacologia , Dano ao DNA , Neoplasias/tratamento farmacológico , Oxidantes/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Células CHO , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quelantes/farmacologia , Ensaio Cometa , Cobre/química , Ácidos Cumáricos/química , Cricetulus , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/farmacologia , Células HEK293 , Células Hep G2 , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Oxidantes/química , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
15.
Tumour Biol ; 36(2): 1237-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25344215

RESUMO

6-Mercaptopurine (6MP) is a well-known purine antimetabolite used to treat childhood acute lymphoblastic leukemia and other diseases. Cancer cells as compared to normal cells are under increased oxidative stress and show high copper level. These differences between cancer cells and normal cells can be targeted to develop effective cancer therapy. Pro-oxidant property of 6MP in the presence of metal ions is not well documented. Redox cycling of Cu(II) to Cu(I) was found to be efficiently mediated by 6MP. We have performed a series of in vitro experiments to demonstrate the pro-oxidant property of 6MP in the presence of Cu(II). Studies on human lymphocytes confirmed the DNA damaging ability of 6MP in the presence of Cu(II). Since 6MP possesses DNA damaging ability by producing reactive oxygen species (ROS) in the presence of Cu(II), it may also possess apoptosis-inducing activity by involving endogenous copper ions. Essentially, this would be an alternative and copper-dependent pathway for anticancer activity of 6MP.


Assuntos
Antineoplásicos/administração & dosagem , Mercaptopurina/administração & dosagem , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Cobre/metabolismo , Dano ao DNA/efeitos dos fármacos , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
16.
Arch Biochem Biophys ; 576: 49-60, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25951786

RESUMO

Drug-DNA interactions have been extensively studied in the recent past. Various techniques have been employed to decipher these interactions. DNA is a major target for a wide range of drugs that may specifically or non-specifically interact with DNA and affect its functions. Interaction between small molecules and DNA are of two types, covalent interactions and non-covalent interactions. Three major modes of non-covalent interactions are electrostatic interactions, groove binding and intercalative binding. This review primarily focuses on discussing various techniques used to study non-covalent interactions that occur between drugs and DNA. Additionally, we report several techniques that may be employed to analyse the binding mode of a drug with DNA. These techniques provide data that are reliable and simple to interpret.


Assuntos
DNA/metabolismo , Substâncias Intercalantes/farmacologia , Preparações Farmacêuticas/metabolismo , Animais , Sítios de Ligação , DNA/química , Humanos , Substâncias Intercalantes/química , Substâncias Intercalantes/metabolismo , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Preparações Farmacêuticas/química , Eletricidade Estática
17.
Arch Biochem Biophys ; 566: 7-14, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25528167

RESUMO

Non-covalent interactions of chlorambucil with calf thymus DNA was investigated using multi-spectroscopic techniques and molecular docking study. Binding constant calculated was found to be 1.54×10(4)M(-1) at 290K, significantly lower than various known intercalators. Quenching process was found to be static as evident by biomolecular quenching constant. Thermodynamic parameters revealed the involvement of hydrophobic interactions and hydrogen bonds in the binding. Chlorambucil was found to interact via external binding mode and follow groove binding as it replaces Hoechst (a typical groove binder) from the groove of DNA but does not replace intercalating dyes including ethidium bromide and acridine orange from the DNA helix. These results were further supported by KI quenching experiments, DNA melting studies, CD spectroscopy and molecular docking.


Assuntos
Antineoplásicos Alquilantes/química , Clorambucila/química , DNA/química , Laranja de Acridina/química , Animais , Bisbenzimidazol/química , Bovinos , Etídio/química , Ligação de Hidrogênio , Cinética , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Análise Espectral , Termodinâmica
18.
Trop Med Int Health ; 20(10): 1376-84, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26094960

RESUMO

OBJECTIVE: To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh. METHODS: Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert(®) blood cultures and real-time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test-it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S. Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid-test cassette lateral flow assay detecting IgG and IgM antibodies against S. Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against S. Typhi proteins. RESULTS: In 300 malaria smear-negative febrile patients [median (IQR) age of 13.5 (5-31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for S. Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for S. Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR-confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut-off of ≥2+ and analysed using a Bayesian latent class model. CONCLUSIONS: These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed.


Assuntos
Testes Diagnósticos de Rotina/normas , Rickettsia/isolamento & purificação , Salmonella enterica/isolamento & purificação , Febre Tifoide/diagnóstico , Adolescente , Adulto , Bangladesh , Criança , Pré-Escolar , Dengue/diagnóstico , Testes Diagnósticos de Rotina/métodos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Leptospirose/diagnóstico , Masculino , Sensibilidade e Especificidade , Adulto Jovem
19.
Phys Chem Chem Phys ; 17(21): 13837-50, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25761147

RESUMO

Ibuprofen is an important nonsteroidal anti-inflammatory drug endowed with various pharmacological and biological activities. In the present study, the photochemical properties of ibuprofen were evaluated by assaying the generation of various reactive oxygen species (ROS) such as superoxide, singlet oxygen and the hydroxyl radical. ROS generated by ibuprofen in the presence of white light causes DNA strand scission as observed by plasmid nicking assay. Ibuprofen induced ROS generation is also capable of causing DNA degradation in lymphocytes as observed by photocomet assay. ROS generation properties of ibuprofen were further strengthened by the formation of carbonyl groups in BSA and TBARS in linoleic acid as observed by carbonyl assay and lipid peroxidation assay respectively. We have also investigated the mode of interaction of ibuprofen with calf thymus DNA through a series of in vitro experiments. UV-visible spectroscopy established the formation of a complex between ibuprofen and Ct DNA. The steady state fluorescence experiments at different temperatures revealed a binding constant of ∼10(4) L mol(-1), which is indicative of intercalative binding between ibuprofen and the DNA helix. Analysis of the various thermodynamic parameters ΔG, ΔH and ΔS calculated at different temperatures indicated that the hydrogen bonds played a major role in the interaction. The intercalative binding mode is further confirmed by competitive displacement assays, urea denaturation, iodide quenching, viscosity measurements and CD analysis. In silico molecular docking revealed the binding of ibuprofen within the GC base pairs of DNA, confirming the intercalative binding mode.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , DNA/metabolismo , Ibuprofeno/efeitos adversos , Substâncias Intercalantes/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Animais , Bovinos , DNA/química , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Humanos , Luz , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Simulação de Acoplamento Molecular , Fotólise/efeitos dos fármacos , Fotólise/efeitos da radiação , Termodinâmica
20.
J West Afr Coll Surg ; 14(2): 199-207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562390

RESUMO

Background: Oral and maxillofacial surgery (OMFS) is the surgical specialty concerned with the treatment of a broad range of conditions that affect the head, face, mouth, neck, and jaw. In Africa, there is a paucity of information about the specialist training available to aspiring African Oral and Maxillofacial Surgeons. Objective: This paper aimed at shedding light on the available OMFS specialist training programmes and training pathways across Africa. Materials and Methods: The authors searched on PubMed, AJOL, and Google Scholar using the keywords "Africa," "Oral and Maxillofacial Surgery," "Residency," "Postgraduate," and "Education" and the individual African countries in English and official languages from inception till July 11, 2022. The authors utilised a questionnaire to interview native oral and maxillofacial surgeons and dentists in African countries where there were no published data on OMFS specialist training. Results: A total of 21 (38.8%) African countries had OMFS specialist training programmes (n = 69). The duration of training varies between 2 and 7 years. The number of training programmes per country ranges between one and thirteen. Countries with the most training programmes for OMFS in Africa are Nigeria, Egypt, Sudan, and Algeria. Northern Africa and Central Africa had the most and least numbers of specialist training programmes in OMFS, respectively. Conclusion: There remains a disparity in the number of specialist training programmes available to aspiring African Oral and Maxillofacial Surgeons as compared with other parts of the world. This paper is intended to function both as a means of advocacy to increase funding and resources in support of the infrastructure and development of facilities for African OMFS specialist training programmes and also serve as a valuable reference for future research in OMFS.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA