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1.
Curr J Neurol ; 22(1): 58-62, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011356

RESUMO

Background: We believe that designing a new tool which is comparable in terms of both sensitivity and specificity may play an important role in rapid and more accurate diagnosis of acute ischemic stroke (AIS) in prehospital stage. Therefore, we intended to develop a new clinical tool for the diagnosis of AIS in the prehospital stage. Methods: This was a cross-sectional diagnostic accuracy study. All patients transferred to the emergency department (ED) who underwent brain magnetic resonance imaging (MRI) with impression of AIS were evaluated by 9 clinical tools for stroke diagnosis in the pre-hospital phase including Rapid Arterial Occlusion Evaluation (RACE), Cincinnati Prehospital Stroke Scale (CPSS), Los Angeles Prehospital Stroke Screen (LAPSS), Melbourne Ambulance Stroke Screen (MASS), Medic Prehospital Assessment for Code Stroke (Med PACS), Ontario Prehospital Stroke Screening Tool (OPSS), PreHospital Ambulance Stroke Test (PreHAST), Recognition of Stroke in the Emergency Room (ROSIER), and Face Arm Speech Test (FAST), and totally 19 items were reviewed and recorded. The new clinical tool was developed based on backward method of multivariable logistic regression analysis. The discrimination power of the new clinical tool for diagnosis of AIS was assessed with the area under the receiver operating characteristic curve (AUC-ROC). Results: Data from 806 patients were analyzed; of them, 57.4% were men. The mean age of the study patients was 66.9 years [standard deviation (SD) = 13.9]. In the multivariable model, 8 items remained. The AUC-ROC of the new clinical tool was 0.893 [95% confidence interval (CI): 0.869-0.917], and its best cut-off point was score ≥ 3 for positive AIS. At this cut-off point, sensitivity and specificity were 84.42% and 79.72%, respectively. Conclusion: We introduced a new nomogram-based clinical tool for the diagnosis of AIS in the prehospital stage, which has acceptable specificity and sensitivity; moreover, it is comparable with previous tools.

2.
BMC Emerg Med ; 23(1): 51, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226097

RESUMO

OBJECTIVE: It seems that the available data on performance of the Rapid Arterial oCclusion Evaluation (RACE) as a prehospital stroke scale for differentiating all AIS cases, not only large vessel occlusion (LVO), from the stroke mimics is lacking. As a result, we intend to evaluate the accuracy of the RACE criteria in diagnosing of AIS in patients transferred to the emergency department (ED). METHOD: The present study was a diagnostic accuracy cross-sectional study during 2021 in Iran. The study population consist of all suspected acute ischemic stroke (AIS) patients who transferred to the ED by emergency medical services (EMS). A 3-part checklist consisting of the basic and demographic information of the patients, items related to the RACE scale, and the final diagnosis of the patients based on interpretation of patients' brain MRI was used for data collection. All data were entered in Stata 14 software. We used the ROC analysis to evaluate the diagnostic power of the test. RESULT: In this study, data from 805 patients with the mean age of 66.9 ± 13.9 years were studied of whom 57.5% were males. Of all the patients suspected of stroke who transferred to the ED, 562 (69.8%) had a definite final diagnosis of AIS. The sensitivity and specificity of the RACE scale for the recommended cut-off point (score ≥ 5) were 50.18% and 92.18%, respectively. According to the Youden J index, the best cut-off point for this tool for differentiating AIS cases was a score > 2, at which sensitivity and specificity were 74.73% and 87.65%, respectively. CONCLUSION: It seems that, the RACE scale is an accurate diagnostic tool to detect and screen AIS patients in ED, Of course, not at the previously suggested cut-off point (score ≥ 5), but at the score > 2.


Assuntos
Arteriopatias Oclusivas , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudos Transversais , Serviço Hospitalar de Emergência , Acidente Vascular Cerebral/diagnóstico , Arteriopatias Oclusivas/diagnóstico
3.
Environ Monit Assess ; 195(6): 748, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37246186

RESUMO

This paper reports a novel, low-cost, and facile approach to prepare a hybrid material consisting of zeolite, Fe3O4, and graphitic carbon nitride as a sorbent to remove methyl violet 6b (MV) from aqueous solutions. To improve the performance of the zeolite for the removal of MV, graphitic carbon nitride (with different C-N bonds and conjugated π region) was used. Also, to perform an easy and fast separation of sorbent from aqueous media, magnetic nanoparticles were incorporated into the sorbent. The prepared sorbent was characterized by different analytical techniques such as X-ray diffraction analysis, Fourier transform infrared, field emission scanning electron microscopy, and energy-dispersive X-ray analysis. The effects of four parameters of initial pH, initial concentration of MV, contact time, and the adsorbent amount on the removal process were investigated and optimized by the central composite design method. The removal efficiency of MV was modeled as a function of the experimental parameters. Affording to the proposed model, the values of 10 mg, 28 mg L-1, and 2 min were selected as optimum condition for adsorbent amount, initial concentration, and contact time, respectively. Under this condition, the optimal removal efficiency was 86% ± 2.8 which were close to the predicted value of the model (89%). Therefore, the model could fit and predict the data. The maximal adsorption capacity of sorbent derived from Langmuir's isotherm was 384.6 mg g-1. The applied composite can efficiently remove MV from various wastewater samples (paint, textile industries, pesticide production wastewater samples, and municipal wastewater).


Assuntos
Poluentes Químicos da Água , Zeolitas , Águas Residuárias , Violeta Genciana , Monitoramento Ambiental , Água/química , Poluentes Químicos da Água/química , Adsorção , Cinética
4.
Arch Acad Emerg Med ; 11(1): e23, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36919139

RESUMO

Introduction: Just as failure to diagnose an acute ischemic stroke (AIS) in a timely manner affects the patient's outcome; an inaccurate and misplaced impression of the AIS diagnosis is not without its drawbacks. Here, we introduce a two-stage clinical tool to aid in the screening of AIS cases in need of imaging in the emergency department (ED). Methods: This was a multicenter cross-sectional study, in which suspected AIS patients who underwent a brain magnetic resonance imaging (MRI) were included. The 18 variables from nine existing AIS screening tools were extracted and a two-stage screening tool was developed based on expert opinion (stage-one or rule in stage) and multivariate logistic regression analysis (stage-two or rule out stage). Then, the screening performance characteristics of the two-stage mode was evaluated. Results: Data from 803 patients with suspected AIS were analyzed. Among them, 57.4 % were male, and their overall mean age was 66.9 ± 13.9 years. There were 561 (69.9%) cases with a final confirmed diagnosis of AIS. The total sensitivity and specificity of the two-stage screening model were 99.11% (95% CI: 98.33 to 99.89) and 35.95% (95% CI: 29.90 to 42.0), respectively. Also, the positive and negative predictive values of two-stage screening model were 78.20% (95% CI: 75.17 to 81.24) and 94.57% (95% CI: 89.93 to 81.24), respectively. The area under the receiver operating characteristic (ROC) curve of the two-stage screening model for AIS was 67.53% (95% CI: 64.48 to 70.58). Overall, using the two-stage screening model presented in this study, more than 11% of suspected AIS patients were not referred for MRI, and the error of this model is about 5%. Conclusion: Here, we proposed a 2-step model for approaching suspected AIS patients in ED for an attempt to safely exclude patients with the least probability of having an AIS as a diagnosis. However, further surveys are required to assess its accuracy and it may even need some modifications.

5.
Environ Res ; 225: 115507, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36828253

RESUMO

Methylene Blue (MB) is a cationic dye causing various health problems such as asthma, heartbeat, eye and skin irritation, nausea, and distress during prolonged exposure. In this regard, the green magnetite nanoparticle was synthesized using the extract of Prosopis farcta. The synthesized Fe3O4nanoparticle was characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), Fourier transforms Infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET). The corresponding parameters, including the primary concentration of MB (5-65 mg/L), the dose of synthesized nanoparticle (0.025-0.925 g/L), solution pH (3-11), and contact time (20-60 min), were considered. Also, central composite design (CCD), as one of the response surface methodologies (RSM), was used for the related modelling and optimization. The particle size of the adsorbent was between 5 and 70 nm, and the nanoparticle has 206.75 m2/g of a specific surface, 6.1 nm of average pore size, and 0.3188 cm3/g of the total pore volume. The optimal conditions for MB removal by the nanoparticle were found to follow an initial MB concentration of 20 mg/L, 0.7 g/L of the nanoparticle dose, pH = 9, and a contact time of 50 min. The pseudo-second-order (PSO) and Freundlich models were the best kinetic and isothermal models for MB removal by the synthesized nanoparticle. Molecular modelling was used to optimize the MB molecular configuration and compute HOMO-LUMO energies, quantum-chemical descriptors, and molecular electrostatic potential to evaluate the nature reactivity of the MB molecule.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Azul de Metileno/química , Adsorção , Nanopartículas/química , Microscopia Eletrônica de Varredura , Cinética , Poluentes Químicos da Água/química , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Membranes (Basel) ; 12(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36135873

RESUMO

Electroplating generates high volumes of rinse water that is contaminated with heavy metals. This study presents an approach for direct metal recovery and recycling from simulated rinse water, made up of an electroplating electrolyte used in industry, using reverse osmosis (RO). To simulate the real industrial application, the process was examined at various permeate fluxes, ranging from 3.75 to 30 L·m−2·h−1 and hydraulic pressures up to 80 bar. Although permeance decreased significantly with increasing water recovery, rejections of up to 93.8% for boric acid, >99.9% for chromium and 99.6% for sulfate were observed. The final RO retentate contained 8.40 g/L chromium and was directly used in Hull cell electroplating tests. It was possible to deposit cold-hued chromium layers under a wide range of relevant current densities, demonstrating the reusability of the concentrate of the rinsing water obtained by RO.

7.
Arch Iran Med ; 24(6): 453-460, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488307

RESUMO

BACKGROUND: Stroke is one of the most common debilitating diseases. Although effective treatment is available, a golden time has been defined in this regard. Therefore, prompt action is needed to identify patients with stroke as soon as possible, even in the pre-hospital stage. In recent years, several clinical scales have been introduced for this purpose. We performed the present study to examine the accuracy of eight clinical scales in terms of stroke diagnosis. METHODS: This multicenter diagnostic accuracy study was conducted in 2019. All patients older than 18 years who were admitted to the emergency department (ED) and underwent brain magnetic resonance imaging (MRI) for a suspected stroke were eligible. All data were gathered through a pre-prepared checklist consisting of three sections, using the clinical records of the patients. The first section of the checklist included basic characteristics and demographic data. The second part included physical examination findings of 19 items related to the 8 scales. The third part was dedicated to the final diagnosis based on the interpretation of brain MRI, which was considered the gold standard for the diagnosis of acute ischemic stroke (AIS) in the current study. RESULTS: The data from 805 patients suspected of stroke were analyzed. In all, 463 patients (57.5%) were male. The participants' age was 6-95 years with a mean age of 66.9 years (SD = 13.9). Of all the registered patients, 562 (69.8%) had an AIS. The accuracy of screening tests was 63.0% to 84.4%. The sensitivity and specificity were 71.9% to 95.7% and 46.5% to 82.8%, respectively. Among all the screening tests, Los Angeles Pre-Hospital Stroke Screening (LAPSS) had the lowest sensitivity, and Medic Prehospital Assessment for Code Stroke (Med PACS) had the highest sensitivity. In addition, Pre-Hospital Ambulance Stroke Test (PreHAST) had the lowest specificity and LAPSS had the highest specificity. CONCLUSION: Based on the findings of the present study, highly sensitive tests that can be used in this regard are Cincinnati Prehospital Stroke Scale (CPSS), Face-Arm-Speech-Time (FAST), and Med PACS, all of which have about 95% sensitivity. On the other hand, none of the studied tools were desirable (specificity above 95%) in any of the examined cut-offs.


Assuntos
Isquemia Encefálica , Serviços Médicos de Emergência , Acidente Vascular Cerebral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Acidente Vascular Cerebral/diagnóstico , Adulto Jovem
8.
Turk J Emerg Med ; 21(1): 1-5, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33575508

RESUMO

OBJECTIVES: In this study, we aimed to investigate the accuracy of recognition of stroke in the Emergency Room (ROSIER) Scale in the diagnosis of patients with acute ischemic stroke (AIS) transferred to the emergency department (ED). METHODS: The present study was a multicenter study. Records from patients suspected of stroke, who referred to the ED were reviewed. Demographic, clinical, and diagnostic data were extracted and then entered in checklists. ROSIER Scale was used to evaluate the possible diagnosis in this study. The definitive diagnosis of a stroke was made based on neurologist's assessment and clinical and neuroimaging findings, mainly brain magnetic resonance imaging (MRI). Receiver operating characteristic (ROC) curve analysis was conducted for assessing the accuracy of ROSIER in discrimination of stroke. RESULTS: The data of 356 suspected stroke patients were analyzed. Of all, 186 patients (52.2%) were male, and the mean age was 65.2 (standard deviation = 14.0) years ranging from 26 to 95 years. One hundred and fifty-one patients (42.4%) had AIS based on the final diagnosis. The area under the ROC curve was 0.85. The best cutoff point for ROSIER scale was ≥1 with a sensitivity of 85.4% (95% confidence interval [CI]: 78.8, 90.6%) and specificity of 65.8% (95% CI: 58.9, 72.3%). CONCLUSION: Based on the findings, although the best cutoff point was the same as the original (derivation) study, its sensitivity (85.4% vs. 92%) and specificity (65.8% vs. 86%) were considerably lower.

9.
Int J Nanomedicine ; 15: 1693-1708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210560

RESUMO

INTRODUCTION: Cancer treatment using functionalized vehicles in order to block involved genes has attracted a remarkable interest. In this study, we investigated the cellular uptake and cytotoxic effects of three sizes of anti Bcl-2 DNAi-conjugated gold nanoparticles by MCF-7 cells. METHODS: Three different sizes of gold nanoparticles were synthesized by citrate reduction method and after characterization, the nanoparticles were functionalized by Bcl-2 targeted DNAi. Cell internalization of the nanoparticles was analyzed by atomic absorption spectroscopy and light microscopy. The cytotoxic effects of the nanoparticles were investigated by MTT assay, flow cytometry and RT-PCR of the target gene. RESULTS: While poor cell internalization of bare gold nanoparticles was observed, the results demonstrated that cellular uptake of DNAi-conjugated gold nanoparticles is completely size-dependent, and the largest nanoparticle (~42 nm) revealed the highest internalization rate compared to other sizes (~14 and ~26 nm). Experimental findings showed that the DNAi-conjugated gold nanoparticles induced apoptotic pathway by silencing of the targeted Bcl-2 gene. In addition, supplementary theoretical studies demonstrated that the 42 nm DNAi-conjugated gold nanoparticles have great photothermal conversion efficiency for treatment under external illumination and these nanoparticles can be induced further cytotoxic effect by approximately 10°C temperature elevations. CONCLUSION: Remarkable photothermal properties of DNAi-conjugated 42 nm Au-NPs in parallel with their high cell internalization and cytotoxic effects introduce them as potential dual functional anticancer nanosystems.


Assuntos
DNA/administração & dosagem , Inativação Gênica , Nanopartículas Metálicas/química , Oncogenes , Proteínas Proto-Oncogênicas c-bcl-2/genética , Apoptose , Linhagem Celular Tumoral , Endocitose , Ouro/química , Humanos , Células MCF-7 , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Espectrofotometria Ultravioleta , Temperatura
10.
Curr J Neurol ; 19(4): 196-199, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-38011376

RESUMO

Background: Andsberg et al. have recently introduced a novel scoring system entitled "PreHospital Ambulance Stroke Test (PreHAST)", which helps to early identification of patients with acute ischemic stroke (AIS) even in prehospital setting. Its validity has not been assessed in a study yet, and the purpose of this study was to assess this scoring system on a larger scale to provide further evidence in this regard. Methods: This was a cross-sectional multi-center accuracy study, in which, sampling was performed prospectively. All patients over 18 years of age admitted to the emergency department (ED) and suspected as AIS cases were included. All required data were recorded in a form consisting of 3 parts: baseline characteristics, neurological examination findings required for calculating PreHAST score, and the ultimate diagnosis made from interpretation of their brain magnetic resonance imaging (MRI). Results: Data from 805 patients (57.5% men) with the mean age of 67.1 ± 13.6 years were analyzed. Of all the patients presenting with suspected AIS, 562 (69.8%) had AIS based on their MRI findings. At the suggested cut-off point (score ≥ 1), PreHAST had a specificity of 46.5% [95% confidence interval (CI): 40.1%-53.0%) and a sensitivity of 93.2% (95% CI: 90.8%-95.2%). Conclusion: According to the findings of our study, at the suggested cut-off point (score ≥ 1), PreHAST had 93.2% sensitivity and 46.5% specificity in detection of patients with AIS, which were somewhat different from those reported in the original study, where 100% sensitivity and 40% specificity were reported for this scoring system.

12.
Ultrason Sonochem ; 50: 239-250, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30274892

RESUMO

The magnetic Ni-Ag bimetallic nanoparticles supported on reduced graphene oxide (Ni-Ag NPs/rGO) was synthesized and characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), field emission scanning electron microscopy (FE-SEM) and vibrating sample magnetometer (VSM). Subsequently, this magnetic hybrid material as a novel adsorbent was applied for the sonochemical simultaneous removal of sunset yellow and tartrazine dyes in combination with first-order derivative spectrophotometric method to resolve the overlap between the spectra of these dyes. With magnetic properties, the adsorbent could easily be collected from aqueous solution using an external magnetic field. The parameters including initial concentration of each dye, adsorbent dosage and sonication time were studied by Box-Behnken design (BBD) and response surface methodology (RSM), while pH was studied by one-at-a-time approach. According to Box-Behnken design based on desirability function (DF), the best experimental conditions was set as initial sunset yellow concentration 10 mgL-1, initial tartrazine concentration 8.5 mgL-1, adsorbent dosage 0.045 g and sonication time of 15 min. The equilibrium data was fitted to different isotherm models and the results revealed the suitability of the Langmuir model. The maximum sorption capacity calculated from the Langmuir model was 28.57 and 26.31 mg g-1 for sunset yellow and tartrazine, respectively. Kinetic data revealed that the adsorption process followed a pseudo-second-order model. The reusability of the magnetite nanoparticles revealed about 8% decrease in the removal efficiency within four consecutive runs.

13.
Med J Islam Repub Iran ; 31: 78, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29445706

RESUMO

Background: Tremendous difficulties are imposed on families with preterm and premature babies, both at birth and during their lifetime. The present study aimed at evaluating the potential economic impact of preterm and premature birth in Iran. Methods: In this descriptive cross-sectional study (2014-2015), we studied preterm and premature newborns, who have been subjected to hospitalization in Ali-Asghar hospital. We followed social perspective to estimate the economic consequences of preterm and premature birth in 3 categories of direct medical, direct non-medical, and indirect costs. Required data were collected from documents in the NICU, and studying medical records, and interviewing their parents. Data were analyzed by Microsoft Excel. Results: Direct medical, direct non-medical and indirect affairs were 84%, 6%, and 10% of the total cost, respectively. The estimated social costs were 373, 529, 189; 508, 774, 181; and 529, 481, 996 US dollars (according to their corresponding incidence of 5.8%, 7.9%, and 9.9%). We also found that 75% of the direct medical costs of initial hospitalization were due to intensive care beds. Conclusion: The economic burden of preterm and premature birth in Iran is considerable and to decrease the costs, it is necessary to implement preventive programs for preterm and premature newborns and to provide management care and support for families dealing with this problem.

14.
Rheumatol Int ; 36(9): 1291-300, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27136919

RESUMO

The aim of this study was to evaluate the effectiveness and cost-effectiveness of using rituximab as first line for patients with refractory rheumatoid arthritis in comparison with continuing conventional DMARDs, from a perspective of health service governors. A systematic review was implemented through searching PubMed, Scopus and Cochrane Library. Quality assessment was performed by Jadad scale. After meta-analysis of ACR index results, QALY gain was calculated through mapping ACR index to HAQ and utility index. To measure the direct and indirect medical costs, a set of interviews with patients were applied. Thirty-two patients were selected from three referral rheumatology clinics in Tehran with definite diagnosis of refractory rheumatoid arthritis in the year before and treatment regimen of either rituximab or DMARDs within last year. Incremental cost-effectiveness ratio was calculated for base case and scenario of generic rituximab. Threefold of GDP per capita was considered as threshold of cost-effectiveness. Four studies were eligible to be considered in this systematic review. Total risk differences of 0.3 for achieving ACR20 criteria, 0.21 for ACR50 and 0.1 for ACR70 were calculated. Also mean of total medical costs of patients for 24 weeks were $3985 in rituximab group and $932 for DMARDs group. Thus, the incremental cost per QALY ratio will be $45,900-$70,223 in base case and $32,386-$49,550 for generic scenario. Rituximab for treatment of patients with refractory rheumatoid arthritis is not considered as cost-effective in Iran in none of the scenarios.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Rituximab/uso terapêutico , Antirreumáticos/economia , Artrite Reumatoide/economia , Análise Custo-Benefício , Humanos , Irã (Geográfico) , Rituximab/economia
15.
Int J Prev Med ; 4(Suppl 2): S279-83, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23776738

RESUMO

BACKGROUND: In adults, throughout life, uniqueness maintains the equivalent; but, it might be tailored in the track of neurological disarrays. As in the partition of cognitive function associated with multiple sclerosis (MS), numerous studies have been performed, but there are very few reports in this area of behavior. The aim of this study was to investigate the prevalence of personality types A and B in relation to individuals' behaviors with MS and type A behavior with demographic characteristics and the level of disability. METHODS: A cross-sectional descriptive study was performed between September 2010 and March 2011 on 50 patients who were referred to MS clinic (located at the Kashani hospital), Isfahan Neurosciences Research Centre (INRC). The subjects were evaluated using Friedman and Rosenman questioner and the Expanded Disability Status Scale (EDSS). The data were analyzed by SPSS software (version 17) based on Chi-square test and independent T-test. RESULTS: Of the subjects, 65% were of personality type A and 35% were of personality type B (X2: 3.5, P < 0.05). There were no significant differences in individuals with type A behavior in relation to gender and marital status. In connection to EDSS (EDSS < 4.5 or EDSS > 4.5), patients with higher EDSS score, i.e., individuals with EDSS > 4.5 mostly had type A behavior pattern. CONCLUSIONS: People with type A behavior pattern are reported to have more stress, nervousness, and anxiety. In this study, MS patients had more characteristics of type A than type B behavior. This behavior was increased in individuals with EDSS score > 4.5.

16.
Int J Biol Macromol ; 56: 169-74, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23415660

RESUMO

The structure changes of hemoglobin (Hb) and glucose oxidase (GOx), as two typical proteins, upon interaction with MWCNTs and MWCNTs-[BMIM]BF4(-) was studied. The ability of MWCNTs and MWCNTs-([BMIM]BF4(-)) for the achievement of direct electrochemistry of GOx and Hb and enhancing the electron transfer rate between proteins and electrode surface was compared. Also the data obtained by various techniques including UV-vis, fluorescence and circular dichroism spectroscopy revealed that the structure of Hb or GOx conjugated with supramolecular network of the nano-composite could be preserved much better than those absorbed on MWCNTs. It seems that ionic liquid provides a favorable microenvironment to maintain the protein native structures.


Assuntos
Aspergillus niger/enzimologia , Glucose Oxidase/química , Hemoglobinas/química , Líquidos Iônicos/química , Nanocompostos/química , Nanotubos de Carbono/química , Temperatura , Carbono/química , Dicroísmo Circular , Eletroquímica , Eletrodos , Vidro/química , Humanos , Imidazóis/química , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
17.
Int J Prev Med ; 3(4): 273-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22624084

RESUMO

BACKGROUNDS: Iron deficiency anemia (IDA) is one of the well recognized presentations of celiac disease (CD). According to the lack of data from our population in this regard, we determined the prevalence of CD in patients presenting with IDA to see if it is worthwhile to do a precise screening for CD in such patients. METHODS: This cross-sectional study was conducted on patients referred with IDA to Poursina Hakim Gastroenterology Clinic, Isfahan (IRAN). All included patients underwent upper gastrointestinal endoscopy and duodenal biopsy. Histopathological changes were assessed according to the Marsh classification. Also, patients were evaluated for IgA anti-tissue transglutaminase (t-TG) antibody with enzyme-linked immunosorbent assay (ELISA) technique. CD was defined as having Marsh II or above histopathology or being seropositive with Marsh I histopathology and having a good response to gluten free diet (GFD). RESULTS: During the study, 130 patients with the mean age of 35.5±13.7 (67.7% female [20.4% post-menopausal]) were undergone seropathological studies. According to histopathological study and a clinical response to GFD, 13 patients (10%) were ultimately diagnosed with CD. Nine patients (6.9%) were seropositive, from which, five patients (3.8%) were ultimately diagnosed as CD cases. IgA anti-tTG became negative in all of these patients after six months of GFD. CONCLUSION: CD should be considered in any adult patient presenting with unexplained IDA, even if not accompanied with gastrointestinal symptoms. Routine duodenal biopsy performed during diagnostic upper gastrointestinal endoscopy is worthwhile in order to investigate for CD as an underlying cause of IDA in adult patients.

18.
Gastroenterol Res Pract ; 2012: 106965, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22545042

RESUMO

Aim. Atypical presentations of celiac disease (CD) have now been shown to be much more common than classical (typical) form. We evaluated the frequency of CD among adult patients with typical or atypical symptoms of CD. Materials and Methods. Patients referred to two outpatient gastroenterology clinics in Isfahan (IRAN) were categorized into those with typical or atypical symptoms of CD. IgA antitissue transglutaminase antibody was assessed and followed by duodenal biopsy. In patients for whom endoscopy was indicated (independent of the serology), duodenal biopsy was taken. Histopathological changes were assessed according to the Marsh classification. Results. During the study period, 151 and 173 patients with typical and atypical symptoms were evaluated (mean age = 32.8 ± 12.6 and 35.8 ± 14.8 years, 47.0% and 56.0% female, resp.). Frequency of CD in patients with typical and atypical symptoms was calculated, respectively, as 5.9% (9/151) and 1.25% (3/173) based on positive serology and pathology. The overall frequency was estimated as at least 9.2% (14/151) and 4.0% (7/173) when data of seronegative patients were also considered. Conclusions. CD is more frequent among patients with typical symptoms of malabsorption and these patients should undergo duodenal biopsy, irrespective of the serology. In patients with atypical symptoms, serological tests should be performed followed by endoscopic biopsy, and routine duodenal biopsy is recommended when endoscopic evaluation is indicated because of symptoms.

19.
Int J Prev Med ; 3(3): 167-72, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22448309

RESUMO

BACKGROUND: Celiac disease (CD) has been found in up to 10% of the patients presenting with unexplained abnormal liver function tests (LFT). As there is no precise data from our country in this regard, we investigated the prevalence of CD in patients presenting with abnormal LFT. METHODS: From 2003 to 2008, we measured IgA anti-tissue transglutaminase (t-TG) antibody (with ELISA technique) within the first-level screening steps for all patients presenting with abnormal LFT to three outpatient gastroenterology clinics in Isfahan, IRAN. All subjects with an IgA anti-tTG antibody value of >10 µ/ml (seropositive) were undergone upper gastrointestinal endoscopy and duodenal biopsy. Histopathological changes were assessed according to the Marsh classification. CD was defined as being seropositive with Marsh I or above in histopathology and having a good response to gluten free diet (GFD). RESULTS: During the study, 224 patients were evaluated, out of which, 10 patients (4.4%) were seropositive for CD. Duodenal biopsies were performed in eight patients and revealed six (2.7%) cases of Marsh I or above (four Marsh IIIA, two Marsh I), all of them had good response to GFD. The overall prevalence of CD among patients with hypertransaminasemia, autoimmune hepatitis, and cryptogenic cirrhosis was determined as 10.7% (3/28), 3.4% (2/59), and 5.3% (1/19), respectively. CONCLUSION: Serological screening with IgA anti-tTG antibody test should be routinely performed in patients presenting with abnormal LFT and especially those with chronic liver diseases including hypertransaminasemia, autoimmune hepatitis, and cryptogenic cirrhosis.

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