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Pressoreceptor reflex or baroreflex is an automatic control mechanism of the cardiovascular system that helps keep homeostasis or maintain blood pressure at a constant level. It is crucial to consider viscoelastic aortic arterial behavior in the pulse wave blood flow to determine the exact distributed location of the aortic arch pressoreceptors. This chapter presents a three-dimensional (3D) healthy man computer tomography model of the aortic arch. Computational Fluid Dynamic and Fluid-Structure Interaction methods were used to obtain the velocity-pressure field in the fluid domain and the stress-strain distribution in the solid domain. We found an increase in the pressure and velocity of the fluid in the aortic arch domain with a maximum of 14.9kPa and 1.4m/s in the systole, respectively. Endothelial cells in the artery wall concave located at the junctures of the supraaortic branches sense the wall shear stress with a value of 20Pa in the systole. Deformation in the aortic artery wall convex reaches over 1mm. The highest normal stress at the supraaortic branches root when sensed through the adventitia layer pressoreceptor is 188kPa. Increasing age of a person leads to an increase in the elastic modulus and adds to the amount of normal stress in the pressoreceptor.

The present work demonstrates the results of a 3D numerical analysis of heat transfer and fluid flow through a fabricated aluminium wire filament, bonded mesh deployed as a regenerator surface in the Stirling engine. Here, two inline regenerator models with the same mass but different geometry were simulated by computational fluid dynamics (CFD) and finite element method (FEM). The results show that the temperature efficiency of both inline with non-uniform and uniform wire diameters is almost equal. However, the non-uniform diameter model is shorter and reaches the maximum thermal efficiency faster in reduced length (Formula presented.). Also, it shows approximately 5% a greater mean thermal efficiency. In general, from this simulation, it can be seen that changes in the geometry of the heat regenerator can have a direct effect on thermal efficiency and pressure drop in the same mass. Therefore, using the inline stacked plain-weave screen with a non-uniform wire diameter regenerator in the powered Stirling engine is recommended due to space constraints. Small changes in the regenerator geometry lead to immense leaps in increasing a solar power plant's overall efficiency.

INTRODUCTION: Most biomarkers in the blood and urine can also be detected in salivary samples. AIMS AND OBJECTIVES: To determine the relationship. between serum and salivary levels of Creatine Kinase MB in patients with acute myocardial infarction. DESIGN: In a case-control study, forty-one patients diagnosed with myocardial infarction and forty- two age and sex- matched controls were enrolled. METHODS: Saliva sampling by the spitting method was performed 12 to 24 hours after myocardial infarction, and in controls, between 9am and 12 noon. Salivary Creatine Kinase MB levels were measured by the photometric method. Mann Whitney U test and Spearman coefficient were used to analyze the data. RESULTS: There was no significant difference between patients with myocardial infarction and the controls in terms of the salivary levels of creatine kinase MB (case: 24 U/l vs. : 19.5 U/l, p=0.30). Patients showed no significant difference in median levels of salivary creatine kinase MB in terms of sex (p=0.69) and previous history of myocardial infarction (p=0.31). In all patients there was a weak positive relationship between serum and salivary levels of creatine kinase MB (rs=0.14, p= 0.39). CONCLUSIONS: Salivary creatine kinase MB level cannot be an indicator for diagnosis of myocardial infarction.

This study was designed to elucidate the effect of ascorbic acid on salivary total antioxidant capacity in smokers. In this single blind crossover clinical trial, the whole unstimulated saliva of 30 smokers, who were randomly divided into two groups, was collected. In the first phase after the saliva collection, one group of patients took 500 mg of vitamin C powder, for 3 weeks. Then, saliva of all patients was collected. After a one-week wash-out period, vitamin C was given to the other group. The collection of saliva was done after 3 weeks. Total antioxidant capacity was measured. Statistic evaluation was performed by Repeated Measured ANOVA, Independent sample t-test and Covariate test. The mean of total antioxidant capacity with and without using vitamin C was 0.511 ± 0.155 (U/mL) and 0.555 ± 0.171 (U/mL), respectively. This variability was not significant (p = 0.605). Oxidative stress from cigarette smoke was not decreased significantly with using vitamin C.

Background: Until now, several formulations of topical phenytoin have been used to promote wound healing. Aim: This study was aimed at re‑evaluating the effects of a newly formulated phenytoin mucoadhesive paste on wound healing after oral biopsy. Subjects and Methods: In a double‑blind clinical trial, 35 consecutive patients with oral lichenoid or lichen planus lesions were randomized into two groups. After incisional biopsy, patients applied simple, or 1% phenytoin paste at least three times a day (after each meal), for 4 days. They were evaluated every other day for size of wound closure, severity of pain, and diameter of the inflammatory halo. This study was approved by Medical Ethics committee of Shahid Beheshti University of Medical Sciences, Tehran, Iran. Statistical analysis was performed using Mann–Whitney U test and Ordinal Logistic Regression. Results: Of 35 patients, 17 (10 [10/17, 59%]) men, 7 (7/17, 41%) women, mean age: 40 (4.11) were in phenytoin group, and 18 (9 [9/9, 50%]) men, 9 (9/9, 50%) women, mean age: 43.1 (5.15) were in placebo group. There were no significant differences between both study groups in terms of age and sex (male/female ratio) (P = 0.76, P = 0.88). As all biopsies were done by means of punch number 8, the incisions were of 10 mm length. After second and third appointments, it was observed that patients in the treatment group showed quicker wound closure and less pain compared to control group significantly (P < 0.05). Although not significant, patients treated with phenytoin paste had smaller inflammatory halo than controls. Conclusion: Applying 1% phenytoin mucoadhesive paste on oral biopsy incisions resulted in accelerated wound healing and decrease in pain.Keywords: Biopsy, Mucoadhesive, Oral, Paste, Phenytoin

This cross sectional study was carried out between 1993 to 1998 at Razi Skin Hospital, the affiliated Dermatology Department of Tehran University of Medical Sciences. Eight hundred patients receiving etretinate for various skin diseases took part in this study. Among them, 457 patients with first admission to dermatologic clinic who had at least four regular sequential visits and responding to our questionnaire were selected to enter the study for evaluating acute toxicity of etretinate. Cheilitis with a frequency of 88 percent was the most frequent side effect. Hair loss (22.97%), dry mouth with thirst (15.09%), dryness of mucous membranes (13.12%), xerosis with pruritus (11.15%), nose bleeding (8.31%), paronychia (5.47%), facial dermatitis (3.06%), conjunctivitis (2.84%) and in addition to mucocutaneous ones, chills (2.63%), headache (2.19%), mental depression (2.19%), urinary frequency (1.53%) and papilledema (0.44%) were among the other observed toxicities, The relationship between mucocutaneous side effect with dosage of etretinate, sex and, age of the patients was evaluated. The association between mucoctaneous toxicities and sex was significant, sex and, age of the patients was evaluated. The association between mucocutaneous toxicities and sex was significant (P

In endemic area the most challenging problem for brucellosis is to find a reliable diagnostic method. In this case-control study, we investigated the accuracy of ELISA test for diagnosis of human brucellosis and determined the optimal cut-off value for ELISA results in Iran. The laboratory diagnosis of brucellosis was performed by blood isolation of Brucella organism with a BACTEC 9240 system and/or detection of Brucella antibodies by standard agglutination test (titer ≥ 1:160). Serum level of ELISA IgG and ELISA IgM from 56 confirmed cases of brucellosis and 126 controls were compared with each other by Box plot graph and Receiver Operating Characteristic (ROC) curve. Box plot graphs showed the high degree of dispersion for IgG and IgM data in patients compared with all controls. We observed partially overlapping for IgM data (not for IgG) between cases and controls in graphs. The area under ROC curve for distinguishing between cases and controls was larger for IgG compared to IgM. Based on results of this study, ELISA IgG test was more reliable than ELISA IgM test in diagnosis of human brucellosis in Iran. Using a cut-off of 10 IU/ml and 50 IU/ml had most sensitivity (92.9%) and most specificity (100%) for ELISA IgG test, respectively.

Pemphigus vulgaris is an autoimmune disease, in which the role of Th17 cytokines needs to be further explored. This study was performed to assess serum levels of three interleukins (IL) required for Th17 differentiation (IL-1β, IL-6 and IL-23) and two specific Th17 cytokines (IL-17 and IL-22) in a group of patients with pemphigus vulgaris, at baseline, 3 weeks and 6 months after of treatment. Correlations between anti-desmogleins and cytokines with disease severity as well as the influence of therapy on the above factors were assessed. Forty-three first-admitted pemphigus vulgaris patients with the active disease entered the study, but only 31 completed the study. Forty-five healthy volunteers were recruited as a control group. The patients were treated with conventional immunosuppressive therapy (oral prednisolone and azathioprine). Cytokines and anti-desmogleins were measured, using enzyme- linked immunosorbent assay. General linear model was used to evaluate the changes over time. In patients at baseline, mean serum level of IL-6 was higher, while mean levels of IL-1β and IL-22 were lower than the controls. After 3 weeks of therapy, IL-1β and IL-6 levels showed a decreasing trend, whereas IL-22 showed an increasing trend. Mean anti-desmogleins 1 and 3 values decreased significantly during the time. Anti-desmoglein values were significantly correlated with disease severity. In conclusion, IL-1β and IL-6 could be involved in the pathogenesis of pemphigus vulgaris. The positive trend of IL-22 is a new finding and should be confirmed by further studies.

The classic treatment for pemphigus vulgaris is prednisolone. Immunosuppressive drugs can be used in association.To compare the efficacy of Azathioprine in reducing the Disease Activity Index (DAI).A double blind randomized controlled study was conducted on 56 new patients, assigned to two therapeutic groups: (i) prednisolone plus placebo; (ii) prednisolone plus Azathioprine. Patients were checked regularly for 1 year. 'Complete remission' was defined as healing of all lesions after 12 months, and prednisolone7.5 mg daily, (DAI ≤ 1). Analysis was done by 'Intention To Treat' (ITT) and 'Treatment Completed Analysis' (TCA).Both groups were similar in age, gender, disease duration, and DAI. Primary endpoint: By ITT and TCA, the mean DAI improved in both groups with no significant difference between them. The difference became significant for the last trimester (3 months; ITT: P = 0.033, TCA: P = 0.045). Secondary endpoint: The total steroid dose decreased significantly in both groups, with no significant difference between them, except for the last trimester (ITT: P = 0.011, TCA: P = 0.035). The mean daily steroid dose decreased gradually in both groups becoming statistically significant in favour of azathioprine, in the last trimester, especially at 12th months (ITT: P = 0.002, TCA: P = 0.005). Complete remission was significant at 12 months only for TCA (AZA/Control: 53.6%/39.9%, P = 0.043).Sample size was rather small to demonstrate all differences. Other limitations include the choice of primary and secondary endpoints and the unavailability to measure thiopurine methyltransferase activity.Azathioprine helps to reduce prednisolone dose in long-run.

Objective: Exposure to mercury can occur in occupational and environmental settings. During clinical work with dental amalgam, the dental personnel are exposed to both metallic mercury and mercury vapor. The aim of the present study was to investigate blood mercury level (BML) and its determinants among dentists practicing in Hamadan city, Iran. Materials and Methods: This cross sectional study was done on all dental practitioners of Hamadan (n=43). Dentists were asked to complete a questionnaire, and then 5 ml blood samples were obtained from them. After preparation, mercury concentration of each sample was measured by cold vapor atomic absorption device. Pearson correlation test and regression models served for statistical analysis. Results: The mean blood concentration of mercury was 6.3 μg/l (SD=1.31 range 4.15- 8.93). BML was positively associated with age, years in practice, working hours per day, number of amalgam restorations per day, number of amalgam removal per week, sea food consumption, working years in present office, using amalgam powder, using diamond bur for amalgam removal, dry sterilization of amalgam contaminated instruments, and deficient air ventilation. Conclusion: BML of dentists in Hamadan was higher than standards. Working hours and number of amalgam restorations per day were significantly correlated with blood mercury.