[Evaluation of clonidine premedication on hemodynamic hyperactivity in patients candidate for ERCP [endoscopic retrograde cholangio pancreatography]]

Autonomic system changes during ERCP lead to increased blood pressure [BP] and heart rate [HR] and decrease in arterial O2 saturation [SPO2]. This study was carried out with the objective of evaluating the clonidine pre-medication effects on systolic BP, HR and SPO2 during ERCP. This randomized clinical trial study was conducted on 40 ERCP candidates. Patients were classified into two groups. The first group didn't receive any premediacation. The patients of second group were given 0.2 mg clonidine 2 hours before ERCP. BP, HR and SPO2 of all patients were recorded before, during and after ERCP. The collected data were analyzed using chi-square, t-test and repeated measures ANOVA [P<0.05]. Age, sex, systolic BP, HR and SPO2 values were identical in both groups before induction [P>0.05]. Analysis of variance of systolic BP, HR and SPO2 showed that SBP and HR changes were significantly lower in the clonidine group at different times [during and after endoscopy] [in the order P<0.004, P<0.017], but no significant difference was observed in SPO2_changes in either groups. The amount of administered sodium thiopental had no significant difference in either group. On the basis of this study, clonidine as an alpha-2 agonist can inhibit BP and HR increase during ERCP by decreasing sympathic discharge but does not decrease the need for sedative drugs

[Evaluation of the effect of 16% carbamide peroxide gel [Nite White] on mercury release from Iranian and foreign spherical and admixed amalgams by cold vapor atomic absorption method]

Nowadays, esthetic dentistry has become an important part of modern dentistry. Bleaching is considered as a conservative, safe and effective way for treatment of discolored teeth. Although bleaching is commonly used on anterior teeth, the bleaching gel may come into contact with patient's former amalgam restorations and result in corrosive effects, dissolution of amalgam phases and increasing release of mercury. Mercury released from dental amalgam during mouthguard bleaching can be absorbed and increase the total mercury body burden. The aim of this study was to determine the amount of mercury released from Iranian and foreign brands of amalgams with spherical and admixed particles, polished and unpolished, after 16% carbamide peroxide gel application. This experimental in vitro study was performed on 256 Iranian and foreign amalgam samples with spherical and admixed particles. The provided samples were put in distilled water and classified according to the type of amalgam, shape of particles and quality of surface polishing. The test samples were placed in Nite White 16% carbamide peroxide gel and control samples were put in phosphate buffer [Ph=6.5] for 14 and 28 hours. The amount of released mercury was calculated using AVA-440 Mercury Analysis System [Thermo Jarrell Ash model SH/229] with cold-vapor atomic absorption. Data were analyzed using t-test, four way and three way ANOVA tests with P<0.05 as the level of significance. 16% Nite White carbamide peroxide gel caused a significant increase in amount of mercury released from amalgams in all groups [P<0.05]. Mercury release from Iranian amalgam was higher than that from the foreign brands [P<0.05]. There was no significant difference in mercury released from spherical and admixed amalgams [P>0.05]. The amount of mercury released from Iranian and foreign amalgams was time dependent [P<0.05]. Furthermore, the amount of mercury released from unpolished amalgams was higher than polished ones [P<0.05]. the present study indicated that exposure of amalgam to 16% Nite White carbamide peroxide gel causes a significant increase in mercury release from the amalgam which is significantly influenced by the brand, exposure time and surface, polishing

Study of response rate to PCNL therapy for renal and upper ureteral stones

Percutaneous surgery is based on needle and guidewire access to the kidney and the upper urinary tract. This study designed to assess retrospectively the safety and efficacy of the percutaneous nephrolithotripsy [PCNL] for treating the renal and upper Ureteral stones. 613 patients underwent PCNL, between September 2000 and September 2004, for renal or upper ureteral stones in Ekbatan and Beheshti hospitals in Hamadan. PCNL was done as a standard method under X-ray guidance and after tract dilatation with metal dilators; pneumatic lithotripsy was used for fragmentation. Complete clearance was 90.7%. Complete stone free rate among patients who need 1 tract [93.8%] obviously was more than the others that more than 1 tract was needed [61.7%]. Variables such as age, sex, weight, grade of hydronephrosis, type of anesthesia, and incision site did not have effect on stone free rate. PCNL, is a safe and effective method for any type of renal and upper ureteral stone especially in developing countries that renal stone is more common

[Relation between fasting during follicular phase of last menstrual period [LMP] and newborn's gender]

Fasting which is a fairly long period of hungry [about 15 hours], causes metabolic changes in human. The meal program is changed during the fasting, so the level of hormonal secretion and electrolytes will be alterd. These changes could possibly affect the gender of newborns that were born from fasting mothers. In this cross-sectional study, the questionair were filled in by mothers who delivered their babies from July 27[th] to September 11th 2004 in Hamadan Fatamieh Hospital. The pregnancy of these mothers were concurrent with the last Ramadhan month. The sex of neonates delivered by 196 mothers who were fasted for at least ten days and their follicular phase of Last Menstrual Period [LMP] corresponded with last Ramadhan month was compared with 175 mothers who did not fast as control group. The data analysed by X[2] test and p<0.05 considered as a significant difference. The results showed that the sex ratio in the newborns of fasted mothers with the mean age of 5.06 years was in favor of boys [156 cases, 78.6%], which was +/- 23.27 significantly [p<0.0001] more than the control group with the mean age of [23.57 +/- 4.93 years] [80 cases 45.7%]. Fasting in the follicular phase of LMP, could possibly change the sex ratio of newborns in favor of boys. Further investigations in different geographical places focussing on race and diet especially during the Ramadhan month are warranted

[Percutaneous nephrolithotomy in the management of pediatric renal calculi]

Pediatric renal calculus disease has been a management dilemma. Achieving excellent results with percutaneous nephrolithotomy [PCNL] in adults have led to use this technique in children. Our experience with this procedure in pediatric age group is reviewed and discussed. In a descriptive cross-sectional study, we retrospectively analyzed case records of 39 patients younger than 15 years who underwent PCNL between September 2000 and April 2004. Antegrade percutaneous access was obtained in all patients and the tract was dilated to 24F. Pneumatic lithotripsy and forceps extraction were used with a rigid nephroscope to disintegrate and remove stones. In all patients, a nephrostomy tube was placed intraoperatively, and a plain abdominal X-ray and nephrostogram were obtained postoperatively. Complete clearance was achieved in 36 patients [92.3%] and relative clearance in 3 patients [7.7%]. Of these, 33 [91.7%] required a single tract, while 2 [5.6%] required two tracts and only one patient [2.8%] required 3 tracts. The greatest stone diameter in 11 [30.5%] patients was less than 20 mm and in 20 [55.6%] patients was more than 20 mm or multiple; 5 [13.9%] patients had staghorn stones. Stone location was lower calyx in 2 [5.1%], upper calyx in 3 [7.7%], renal pelvis in 15 [38.5%], and staghorn or multiple in 19 [48.7%] subjects. Open surgery was not required in any patient, and patients with residual stone after second look surgery were sent for SWL treatment. There was no contiguous organ injury, and no open surgery or blood transfusions were required. Percutaneous nephrolithotomy is safe and effective in children, and should be considered as a viable management option. However, staghorn and multiple renal calculi may require alternative managements

effect of collagen removal on shear bond strength of four single bottle adhesive systems

Achieving adhesion between restorative materials and dentin as a wet and dynamic surface is an important topic in restorative and especially in conservative dentistry. Adhesion of new dentin bonding systems depends on the formation of hybrid layer and micromechanical retention. Nevertheless, an ideal adhesive system has not yet been introduced .Recent studies reveal an increase in bonding stability when the collagen is removed from demineralized dentin surfaces. This study investigates the effect of collagen removal on the shear bond strength of four single bottle dentin bonding systems regarding their structural differences. This experimental study was performed on 56 intact human premolar teeth. Smooth surfaces of dentin were prepared on buccal and lingual aspects of teeth, providing 112 dentin surfaces. The dentin surfaces were etched with 37% phosphoric acid for 15 seconds and then rinsed. The specimens were divided into 8 groups. Single bottle adhesive systems [Single Bond [3M], One-Step [Bisco], Prime and Bond NT [Dentsply], and Excite [Vivadent]] were then applied on the dentin surfaces of 4 groups using the wet bonding technique. In the other 4 groups, the demineralized dentin surfaces were treated with a 5.25% solution of sodium hypochlorite for one minute in order to remove the surface organic components. The adhesive systems mentioned before were applied to these 4 groups with the same wet bonding technique. A cylinder of Z100 [3M] dental composite with a 3 mm diameter and 2 mm height was placed on the adhesive covered dentin surface of all groups and light-cured [400 mW/cm2 ,40 sec on each side]. The specimens were kept in distilled water at room temperature for one week and then thermocycled for 3000 times [5-55 °c]. Shear bond strength of specimens was measured using an Instron [1495] universal mechanical testing machine with cross-head speed of 0.5 mm/minute and chisel form shearing blade. Data were analyzed by Two Way ANOVA and Tukey HSD tests with p<0.05 as the limit of significance