Detection of human papillomavirus DNA sequences in oral lesions using polymerase chain reaction

The purpose of the present study was to estimate the frequency of HPV DNA in four groups of oral lesions, including oral squamous cell carcinoma. Sixty paraffin-embedded oral tissue samples were examined for the presence of HPV DNAs using the PCR technique. These specimens were obtained from patients with oral squamous cell carcinoma (OSCC), leukoplakia, oral lichen planus (OLP), and pyogenic granuloma (PG). Consensus primers for L1 region (MY09 and MY11) and specific primers were used for detection of HPV DNA sequences in this study. we detected HPV DNA in 60% (9 out of 15) of OSCCs, 26.7% (4 out of 15) of leukoplakia, 13.3% (2 out of 15) of OLPs, and 6.7% (1 out of 15) of PGs. Statistical analysis showed that the prevalence of HPV in OSCC was significantly higher than other groups (P < 0.05). The frequency of HPV-16 and 18 detection in OSCC samples were 40% and 20%, respectively. The prevalence of these high risk HPVs was significantly higher in OSCC group (P < 0.05). The results of the present study show a successive increase of detection rate of HPV-16 and 18 DNAs from low level in samples of pyogenic granuloma and non-premalignant or questionably premalignant lesions of OLP to premalignant leukoplakia and to OSCC. © 2007 Tehran University of Medical Sciences. All rights reserved

Treatment Failure in Cutaneous Leishmaniasis Patients Referred to the School of Public Health, Tehran University of Medical Sciences During 2008-2017

Background: Cutaneous leishmaniasis (CL) is a vector borne disease predominantly found in tropical and subtropical countries, including Iran. For more than 6 decades, pentavalent antimonials have been used successfully worldwide for the treatment of leishmaniasis, but over the past few years, clinical resistance to these medications has increased. In this study, we evaluated CL patients who did not show any desirable responses to the anti-leishmanial treatment within a 10-year period (2008 to 2017). Methods: All patients from different parts of Iran suspected of having cutaneous leishmaniasis, who were referred to the laboratory of leishmaniosis in Tehran University of Medical Sciences from 2008-2017 were parasitological examined. Results: During this period, a total of 1480 suspected CL patients were referred to the laboratory of leishmaniosis. Samples from 655 patients (70.8) suspected of having CL were positive microscopically. The failure rate in patients treated with anti-leishmaniasis medications for a minimum of three complete treatment periods was 1.83 (12 cases). There was no association between the number and size of skin lesions and patient characteristics. Also, the route of drug administration had no significant effect on the number and size of lesions. Conclusion: In the present study, treatment failure was found in some confirmed CL patients treated with meglumine antimoniate. Over the past few years, it seems that had been increased in resistance to these medications. So, a review of the correct implementation of the treatment protocol and/or a combination therapy may be helpful in preventing an increase in the rate of treatment failure

Synthesis and characterization of Cr-Doped AL2O3 Nanoparticles prepared via aqueous combustion method

Chromium-doped Alumina was synthesized via combustion technique. Nanoparticles were produced from aluminum nitrate, ammonium dichromate, and sucrose. Silver nitrate was used as catalyst. The use of sucrose (C 12 H 22 O 11 ) as dispersion agent and ammonium dichromate both as fuel and a doping agent source are new techniques in the synthesis of Cr-doped Al 2 O 3 nanoparticles. The heat-treated powders were characterized by X- ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Heat treatment of the nanoparticles was performed at temperatures of 900 °C, 1000 °C, and 1100 °C, which resulted in the formation of porous agglomerated chromium-doped alumina nanoparticles. Chromium-doped alumina with an average crystalline size of 35 nm was successfully synthesized via combustion technique with sucrose as fuel

Lighting measurement in Shemiranat health center based on EN 12464-1 European standard

Introduction: Illumination standards especially Illumination Engineering Society of North America (IESNA) and Iran lighting standards (ILS) are just based quantitative measurements. However, lighting has psychological effects and can influence quality and quantity of productivity and comfort of workers. Therefore, Illumination standards were undergone some changes. EN 12464-1 standards focus on the quality and quantity of lighting as well as the energy consumption. The aim of this study was to evaluate quality and quantity of lighting in Shemiranat health center. .Material and Method: In this study, first work tables were divided into 20×20 squares and illuminance was measured by putting HANGER S3 luxmeter sensor on the center of each square. In next stage, the luminance of each lighting source was measured from the view of observe and the average luminance of work table surface was calculated in the divide square. Furthermore, vertical, horizontal and lateral distance between observes eye and lighting source was measured. The gathered information was put in the equation and glare rate was calculated. Finally, according to the table we obtained color rendering index of lighting sources. .Result: Results of this study showed that maintained illuminance dose not mach the standards (500 lux) in any of the work station. Moreover, the glare match the standards just in less than 10 percent of the work area. Therefore, it is essential to reform the artificial lighting system and keep the maintained luminance and glare at the standard level. .Conclusion: There is a dramatic difference between the current lighting condition and the standard values. Therefore, making changes in lighting system is obviously essential

Evaluation of Workers’ Exposure to Methylene Diphenyl Diisocyanate (MDI) in an Automobile Manufacturing Company, Iran

Evaluation of personal inhalation exposure to methylene diphenyl diisocyanate (MDI) among 39 employees, working in the window fixation and window glue processes in an automobile manufacturing company was performed. This study was conducted for both case and control groups. After sampling and sample preparation processes, MDI was determined with a UV-VIS spectrophotometer at 590 nm; the lung function was assessed with a digital spirometer, too. The average concentration of MDI in the window fixation, and window glue workplaces were 34.53 and 27.37 μg/m3, respectively, which was lower than the threshold limit value (TLV) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH) (51 μg/m3). Respiratory symptoms in the exposed group were significantly different compared to the unexposed group (p < .05). Lung capacities in the case group were lower than in the control group (p < .05). Therefore, MDI can be easily measured making it possible to evaluate the adverse effects caused by occupational exposure

Modeling the tensile stress–strain response of carbon nanotube/polypropylene nanocomposites using nonlinear representative volume element

This paper presents a finite element model for predicting the mechanical behavior of polypropylene (PP) composites reinforced with carbon nanotubes (CNTs) at large deformation scale. Existing numerical models cannot predict composite behavior at large strains due to using simplified material properties and inefficient interfaces between CNT and polymer. In this work, nonlinear representative volume elements (RVE) of composite are prepared. These RVEs consist of CNT, PP matrix and non-bonded interface. The nonlinear material properties for CNT and polymer are adopted to solid elements. For the first time, the interface between CNT and matrix is simulated using contact elements. This interfacial model is capable enough to simulate wide range of interactions between CNT and polymer in large strains. The influence of adding CNT with different aspect ratio into PP is studied. The mechanical behavior of composites with different interfacial shear strength (ISS) is discussed. The success of this new model was verified by comparing the simulation results for RVEs with conducted experimental results. The results shows that the length of CNT and ISS values significantly affect the reinforcement phenomenon

Evaluating Poly-Aromatic Hydrocarbons in respiratory zone of the asphalt workers in Tehran city

Introduction: PAHs are organic compounds with benzenic rings that releas from hot asphalt as incomplete combusting. These compounds are one of the major concern in scientific societies, workplace and environment due to their stability, bioaccumulation, carcinogenic and mutagenic effects. Since asphalt workers are exposed to PAHs frequently in their job, in this study it was attempted to evaluate respiratory exposure of asphalt workers to PAHs in their breathing zone. .Material and Method: In this study air samples of the asphalt workers were collected in accordance with the NIOSH 5506 method using PTFE filter and XAD-2 adsorbent. The ultrasonic bath and acetonithrile are used in order to extract the analytes from the filter and adsorbent. Also, the samples were analyzed by HPLC-UV. .Result: In all samples, Finisher assistance and oilman with 1754.48 ng/m3 , 24.65 ng/m3 had maximum and minimum exposed to ∑PAH, respectively. Among the PAHs compounds, which asphalt workers exposed to, Naphtalene had the highest concentration. Among different asphalt workers tasks, screedman expoused to PAHs, had a significant difference. . Conclusion: Evaluation of Polycyclic aromatic hydrocarbons concentrations in the breathing zone of asphalt workers indicated that exposure to these compounds were below the occupational exposure limits recommended by NIOSH, OSAH, ACGIH and Iranian OEL. Due to the highly carcinogenic potential of some of these compounds and absence of occupational exposure limits for these compounds, likes Chrysene and Benzo (a) Anthracene, it is strictly recommended to employ engineering controls and using suitable PPEs. This study also indicated that the exposure to PAHs in the most asphalt workers tasks had significant differences, and it can be due to proximity of the workers to the source of hot asphalt and also exposure to the exhaust gases that releasesd from the construction machinery