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Shilpa Trivedi Nand Lal Abbas Ali Mahdi Madhukar Mittal Babita Singh Shivani Pandey 《Journal of periodontology》2014,85(5):713-720
Background: The aim of this study is to investigate the impact of diabetes, a known risk factor for periodontitis, on activities of antioxidant enzymes superoxide dismutase (SOD), glutathione reductase (GR), and catalase (CAT) as well as levels of free radical damage marker malondialdehyde (MDA) in blood and saliva of individuals with chronic periodontitis (CP). Methods: Sixty patients with CP (30 patients with type 2 diabetes mellitus [DMCP] and 30 systemically healthy patients [CP]) and 60 periodontally healthy individuals (30 patients with type 2 diabetes mellitus and 30 systemically healthy patients [PH]) were included in this study. After clinical measurements, blood and saliva samples were collected. SOD, GR, and CAT activities in red blood cell lysate and saliva and MDA levels in plasma and saliva samples were spectrophotometrically assayed. An analysis of variance test followed by a post hoc test was used to compare the intragroup and intergroup variances among the study groups. Results: MDA levels in both the periodontitis groups were higher than in the periodontally healthy groups, but the difference between the CP and DMCP groups did not reach statistical significance (P >0.05). There was a highly significant difference between the CP and PH groups for all the enzymes studied except for SOD in blood. Only salivary SOD and GR activities were significantly different in the CP and DMCP groups. Conclusions: This study favors the role of oxidative stress in both diabetes and periodontitis. It shows that the compensatory mechanism of the body is partially collapsed because of excessive production of free radicals during periodontitis and is not able to cope with increased free radical generation attributable to diabetes, thereby worsening the situation. 相似文献
63.
Mahnaz Khanavi Mansoureh Sabbagh-Bani-Azad Amir Hossein Abdolghaffari Mahdi Vazirian Isa Isazadeh Mohammad Amin Rezvanfar Maryam Baeeri Azadeh Mohammadirad Roja Rahimi Mohammad Reza Shams-Ardekani Mohammad Abdollahi 《Archives of Medical Science》2014,10(6):1225-1234
Introduction
In this study we investigated the effect of gall of Quercus brantii Lindl., a traditional Iranian medicine, in a murine model of experimental colitis induced in male rats by rectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS).Material and methods
Quantification of the main active components was done for estimation of total phenolic content and free gallic acid. Gall of Quercus brantii Lindl. in two forms (gall powder and gall hydro alcoholic extract) was gavaged for 10 days (500 mg/kg). Ten days after induction of colitis, colonic status was examined by macroscopic, microscopic and biochemical analyses. Colonic tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were analyzed as biomarkers of inflammatory condition. To determine the role of oxidative stress (OS) in colitis, the levels of cellular lipid peroxidation (LPO), total antioxidant power (TAP) and myeloperoxidase (MPO) were measured in colon tissues.Results
TNBS-induced colitis exhibited a significant increase in colon MPO activity and concentrations of cellular LPO, TNF-α and IL-1β, while TAP was significantly reduced. Microscopic evaluations of the colonic damage in the colitis group revealed multifocal degenerative changes in the epithelial lining and areas of necrosis, extensive mucosal and sub-mucosal damage with congested blood vessels, edema and hemorrhages along with extensive infiltration of inflammatory cells. Parameters including macroscopic and microscopic scores, TNF-α, IL-1β, LPO, TAP and MPO improved by both gall extract and gall powder of Quercus brantii Lindl. and reached close to normal levels. The level of total phenols (GAE/100 g of sample) and free gallic acid were estimated to be 88.43 ±7.23 (mean ± SD) and 3.74% of dry weight, respectively.Conclusions
The present study indicates that the gall of Quercus brantii Lindl. is able to exert antioxidative and anti-inflammatory effects on the biochemical and pathological parameters of colitis. 相似文献64.
Fatemeh Bitarafan Seyed Yousef Seyedena Mahdi Mahmoudi Masoud Garshasbi 《Journal of clinical laboratory analysis》2020,34(12):e23544
BackgroundThe extremely high genetic heterogeneity of hearing loss due to diverse group of genes encoding proteins required for development, function, and maintenance of the complex auditory system makes the genetic diagnosis of this disease challenging. Up to now, 121 different genes have been identified for nonsyndromic hearing loss (NSHL), of which 76 genes are responsible for the most common forms of NSHL, autosomal recessive nonsyndromic hearing loss (ARNSHL).MethodsAfter excluding mutations in the most common ARNSHL gene, GJB2, by Sanger sequencing, genetic screening for a panel of genes responsible for hereditary hearing impairment performed in 9 individuals with ARNSHL from unrelated Iranian consanguineous pedigrees.ResultsOne compound heterozygote and eight homozygote variants, of which five are novel, were identified: CDH23:p.(Glu1970Lys), and p.(Ala1072Asp), GIPC3:p.(Asn82Ser), and (p.Thr41Lys), MYO7A:p.[Phe456Phe]; p.[Met708Val], and p.(Gly163Arg), TECTA:p.(Leu17Leufs*19), OTOF:c.1392+1G>A, and TRIOBP:p.(Arg1068*). Sanger sequencing confirmed the segregation of the variants with the disease in each family.ConclusionFinding more variants and expanding the spectrum of hearing impairment mutations can increase the diagnostic value of molecular testing in the screening of patients and can improve counseling to minimize the risk of having affected children for at risk couples. 相似文献
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Tobramycin is an aminoglycoside antibiotic that loses a significant amount of activity in the presence of Zosyn at pH 6. As part of our investigation into ways to improve the compatibility of tobramycin with Zosyn (which contains piperacillin and tazobactam in an 8:1 ratio buffered at pH 6 by sodium citrate) by lowering the pH, we identified the reaction product of tobramycin and piperacillin at pH 6.0 and the order of the pK(a) values of tobramycin. The structure of the main reaction product of tobramycin and piperacillin at pH 6.0 was determined by 2D NMR to be the product of 3″-NH(2) reacting with the β-lactam of piperacillin. The order of the pK(a) values of the nitrogens of tobramycin was determined by (1)H and (15)N NMR titrations to be 6'-NH(2)>2'-NH(2)>1-NH(2)≈3″-NH(2)>3-NH(2). At pH 4.0, the reaction between tobramycin and Zosyn was almost negligible for a period of up to 2?h. The pH can be lowered by adding an acid such as HCl or citric acid to Zosyn to make a pH 4.0 buffer. 相似文献
68.
Mahdi Moshki Fazlollah Ghofranipour Ebrahim Hajizadeh Parviz Azadfallah 《BMC public health》2007,7(1):295
Background
The purpose of the present study was to assess the validity and reliability of Form A of Multidimensional Health Locus of Control scales in Iran. Health locus of control is one of the most widely measured parameters of health belief for the planning of health education programs. 相似文献69.
Muhammad Younus Edward Hartwick Azfar A Siddiqi Melinda Wilkins Herbert D Davies Mohammad Rahbar Julie Funk Mahdi Saeed 《International journal of health geographics》2007,6(1):56
Background:
The majority of U.S. disease surveillance systems contain incomplete information regarding socioeconomic status (SES) indicators like household or family income and educational attainment in case reports, which reduces the usefulness of surveillance data for these parameters. We investigated the association between select SES attributes at the neighborhood level and Salmonella infections in the three most populated counties in Michigan using a geographic information system. 相似文献70.