The effect of silver nanoparticles, zinc oxide nanoparticles, and titanium dioxide nanoparticles on the push-out bond strength of fiber posts

This study was undertaken to investigate the effect of intraradicular dentin pretreatment with silver nanoparticles (SNPs), zinc oxide nanoparticles (ZNPs), and titanium oxide nanoparticles (TNPs) on the push-out bond strength (PBS) of fiber posts to root dentin using two types of resin cements. Eighty single-rooted human premolar roots were randomly divided into eight groups after endodontic treatment and post space preparation, according to the type of intraradicular dentin pretreatment with different nanoparticle solutions (n=20). The groups included no pretreatment (control) and pretreatments with SNPs, ZNPs, and TNPs. Each group was divided into 2 subgroups (n=10) according to cementation: Excite DSC/Variolink II and ED Primer II/Panavia F2.0. The PBS values were measured in different areas of the post space. The data were subjected to the three-way analysis of variance and Tukey tests (p=0.05). The SNP-pretreated groups showed significantly higher PBS values than the other groups. No significant differences in PBS were noted among the control, ZNP-pretreated, and TNP-pretreated groups. There was no significant difference in the PBS of the fiber posts with respect to cement type. The PBS was significantly lower in the apical region than in the other two regions. There was no statistically significant difference between the PBSs of the cervical and middle thirds. Intraradicular dentin pretreatment with SNPs, TNPs, and ZNPs did not interfere with the PBS of the fiber posts. The best result was obtained for the SNP-pretreated groups for both types of cement. Also, the lowest PBS was found in the apical third of the root canal spaces

The effect of pre-pregnancy body mass index and gestational weight gain on pregnancy outcomes in urban care settings in Urmia-Iran

BACKGROUND: Nutritional status of women has been considered an important prognostic indicator of pregnancy outcomes. Few studies have evaluated patterns of weight gain and pre-pregnancy body mass index in developing regions where malnutrition and poor weight gain as well as maternal obesity have significant influences on the pregnancy outcome. This study aims to show effect of pregnancy body mass index and the corresponding gestational weight gain on the outcome of pregnancy. METHODS: On a prospective cross sectional study, two hundred and seventy women from urban areas of Northwest Iran were recruited for participation during their first eight weeks of pregnancy. Body mass index (BMI) was categorized and gestational weight gain was divided into two groups of normal and abnormal based on recommendations of Institute of Medicine (IOM) published in 1990. Chi square and one way ANOVA were used in the univariate analysis of the association between weight gain and corresponding adverse outcomes including cesarean, preterm labor and low neonatal birth weight. Adjusted odds ratios for adverse outcomes were determined by multiple logistic regression models, while controlling for the following factors: maternal age, parity, and education. RESULTS: Both pre-pregnancy BMI < 19 and abnormal weight gain during pregnancy were found to be associated with low neonatal birth weight defined as < 2500 g. Abnormal weight gain, during pregnancy was not related to an increased risk of preterm labor or cesarean delivery but it was highly associated with low birth weight (LBW)(P < 0.05). CONCLUSION: Low pre-pregnancy BMI is an established risk factor for LBW. Abnormal gestational weight gain may further complicate the pregnancy as an additional risk factor for neonatal LBW. All women, regardless of their pre-pregnancy BMI may be at risk for abnormal weight gain and hence low birth weight. Pre-pregnancy and gestation nutritional assessments remain significant part of all prenatal visits

Viable Extreme Preterm Birth and Some Neonatal Outcomes in Double Cerclage versus Traditional Cerclage: A Randomized Clinical Trial

The pregnant women at higher risk of preterm labor, referred to the perinatal clinic of Kosar University Hospital in Urmia district of Iran, were enrolled into a parallel randomized clinical trial. In the investigational arm of the clinical trial, a double cervical cerclage procedure was performed addition to McDonald cerclage. In the control group however, only McDonald cerclage was performed. Extreme preterm labor (GA < 33 weeks) was the primary endpoint of this clinical trial. Age, gestational age at cerclage time, and gravidity were not found to be statistically different between the groups. Means of gestational age were 37.4 and 36.2 weeks, respectively, for the investigational and control groups. The gestational age was 1.2 weeks longer for double cerclage group but the difference was not found to be statistically significant. Preterm birth before 33 weeks of gestation was not experienced by any of the patients who received double cerclage, but five women in control group developed such an extreme preterm labor (P < 0.05). The absolute risk reduction in using double cerclage over traditional method was 18 percent (95% confidence interval, 4%–32%). Double cerclage appeared to have higher efficacy than traditional cerclage in preventing preterm labor <33 weeks of gestation

Reproductive status of male rat offspring following exposure to methamphetamine during intrauterine life: An experimental study

Background: Methamphetamine abuse during pregnancy is associated with maternal and fetal adverse outcomes. Methamphetamine induces reproductive damage in adults; however, its effect has not been studied during pregnancy. Objective: To investigate the effects of methamphetamine exposure during pregnancy on the reproductive system. Materials and Methods: Fifteen pregnant Wistar rats were divided into 3 groups (n = 5/group), they received daily intraperitoneal injections of saline or methamphetamine (5, and 10 mg/kg) from day 10 until the end of pregnancy. One adult male offspring was selected from each dam. Subjects were euthanized, and their testis was removed. Sperm samples from cauda epididymis were analyzed for sperm concentration, morphology, and motility. Terminal deoxynucleotidyl transferase dUTP nick-end labeling assay was used to detect apoptotic cells. Levels of B-cell lymphoma 2 protein (Bcl-2) and Bcl-2 associated X-protein were measured using Western blot. Results: Methamphetamine significantly decreased sperm concentration (5 mg vs. saline: p = 0.001, 10 mg vs. saline: p &lt; 0.001), normal sperm morphology (saline vs. 10 mg: p = 0.001), and motility (p: saline vs. 5 mg = 0.004, 5 mg vs. 10 mg = 0.011, saline vs. 10 mg &lt; 0.001) in a dose-dependent manner. There was a significantly higher number of terminal deoxynucleotidyl transferase dUTP nick-end labeling -positive cells and higher exposure. Moreover, Bcl-2 associated X-protein was increased, and Bcl-2 was decreased in these rats. Conclusion: The present study shows that chronic methamphetamine exposure during intrauterine period can induce apoptosis of seminiferous tubules and decrease sperm quality in adult rats. Moreover, we showed that the intrinsic apoptotic pathway is involved in this process. Further studies are required to identify the complete molecular pathway of these results. Key words: Methamphetamine, Testis, Fertility, Reproduction, Apoptosis, Intrauterine exposure

Clinical, Laboratory, and Obstetrics Features of Novel Coronavirus Disease 2019 (COVID-19) during Pregnancy

Background: The novel coronavirus disease 2019 (COVID-19) remains a new entity; the data on its clinical features, complications, and adverse outcomes during pregnancy are still to be identified and described. Several studies have reported a series of COVID-19 infections in pregnancy, the maternal and the neonatal outcome from different ethnicities and geographical regions. Materials and Methods: This retrospective cross-sectional study was conducted in the obstetrics department of Mahdiyeh Hospital of Tehran, Iran, between February and April 2020. We included a series of 23 singleton pregnancies presenting to our department with fever and dry cough. All patients were tested for COVID-19 infection using nasopharyngeal swabs. Results: We included 23 singleton pregnant patients with a mean age of 28.1 ± 6.16 (ranging from 15 to 39) years and gestational age of 29.96±10.2 [ranging from 7 to 40] weeks. Of these patients, 7 (30.4%) tested positive for the SARS‑CoV‑2. Among the total patient population, 16 (69.5%) had elevated serum levels of C-reactive protein (CRP), 1 [4.3%] had lymphopenia, and 8 (34.7%) had elevated erythrocyte sedimentation rate (ESR). Only 2 (8.7%) patients had positive findings of chest CT-scan. Most newborns had acceptable Apgar and birth weight, and only 4 (17.4%) required NICU admission. Conclusion: The clinical characteristics of the COVID-19 infection in pregnant patients were comparable to those of non-pregnant patients. We did not record a high frequency of lymphopenia and leukopenia, probably due to leukocytosis during pregnancy. CRP was a sensitive marker for COVID-19 pneumonia in pregnant patients

Effect of Some Evaluation Methods on the Consequence of Final Exam for Freshman Medical Students

Background & Objective: In Iran, evaluation is one of the most important bases of medical education and one of the best criteria for the categorization of medical universities. Therefore, we aimed to compare some methods of evaluation for medical students. Methods: The target group included all basic level medical students studying medical mycology during the fifth semester. The tested methods of evaluations were: development test, post-test, class reports, and final exam. Three groups of evaluation were compared as a course plan of mycology for nine sessions. Results: There was a significant direct relation between the midterm and final exam, so that the increased midterm and post-test marks caused improvement in the final exam. Moreover, there was a relative correlation between the class reports and final exam. Conclusion: The results of the present study showed that each tested continuous evaluation is able to improve the final exams. Keywords Evaluation Medical students Final exam Midterm Post-tes

Isothermal, Kinetic, and Thermodynamic Studies on the Adsorption of Molybdenum by a Nanostructured Magnetic Material

In this study, the magnetic 3-(trimethoxysilyl) propyl methacrylate (TMSPMA) – poly (4-vinylpyridine) (P4VP) was synthesized and characterized. Removal of Molybdenum (Mo) from aqueous solutions using prepared material as nanosorbent was investigated. The magnetic P4VP was prepared by copolymerization of P4VP with TMSPMA. The prepared adsorbent was characterized by various techniques including the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). The batch adsorption technique was applied and the effect of several important parameters such as pH of the aqueous solution, adsorbent dose, initial Mo(VI) concentration, contact time, and temperature was evaluated. Desorption behavior of Mo(VI) and the effect of foreign ions (Cd2+, Ca2+, Co2+, Fe3+, Ba2+ and Pt4+) in real samples were also investigated. Co (II) and Pt (IV) had a greater impact on the adsorption process than other foreign ions. The maximum capacity for Mo(VI) adsorption on the prepared adsorbent was 4.87 mg/g, which was obtained at a temperature of 40°C with an initial concentration of 10 mg/L of Mo(VI). The adsorption isotherms were best fitted with the Weber Van Vliet isotherm model. The kinetic data were fitted well with the pseudo-second-order equation with a high correlation coefficient (R2 > 0.99). Based on the negative standard Gibbs free energy change (ΔG° 0), it was found that the adsorption was an endothermic and a spontaneous process in nature