Comparison of maternal 25 (OH) vitamin D levels between premature infants with/without asphyxia.

OBJECTIVES: Perinatal asphyxia is the main risk factor for mortality and morbidity in neonates and neurological disorders in survived infants. We compared the neonatal and maternal 25 (OH) vitamin D levels in neonates with/without asphyxia. MATERIALS AND METHODS: This cross-sectional research was done on 229 neonates (including 158 neonates [69%] without asphyxia [control group] and 71 neonates [31%] with asphyxia [case group]) from 2020 to 2023 using the available sampling method. 25 (OH) Vit D levels in mothers and neonates were assessed and compared in the 2 groups. The data collection instrument was a researcher-made checklist, containing the maternal and neonatal characteristics and laboratory evaluations. Data were analyzed by SPSS 23 using the t-test. RESULTS: The mean maternal 25 (OH) Vit D levels in the case and control groups were 16.34±11.87 and 22.80±12.67 ng/mL, respectively. The mean neonatal 25 (OH) Vit D levels in the case and control groups were respectively 12.13±8.62 and 19.55±11.62 ng/mL (P = 0.002). The case group showed severer maternal and neonatal 25 (OH) Vit D deficiency (P = 0.000) compared to the control group. CONCLUSIONS: Neonatal and maternal 25 (OH) Vit D deficiency can increase the risk of perinatal asphyxia. Therefore, administration of 25 (OH) Vit D supplements to pregnant mothers may reduce the incidence of asphyxia.

Association between waterpipe smoking and lung cancer: a multicentre case-control study in Iran.

OBJECTIVES: This study investigated the association between lung cancer and waterpipe smoking, which is an emerging global public health concern. STUDY DESIGN: Multicentre case-control study. METHODS: This study included 627 cases and 3477 controls from the Iranian Study of Opium and Cancer (IROPICAN) study, which was conducted between 2017 and 2020. One frequency-matched control for each lung cancer patient was selected by age, gender and residential place; however, this study used controls of four cancer types in the analyses. The multivariable logistic regression model estimated the odds ratio (OR) and 95% confidence intervals (CIs). Additional analyses were performed among 181 lung cancer cases and 2141 controls who were not cigarette smokers or opium or nass/pipe users. RESULTS: The odds of lung cancer were higher among waterpipe smokers than never-smokers (OR = 1.3, 95% CI: 1.0-1.7). Results showed a higher OR of lung cancer for those who smoked the waterpipe daily (OR = 2.1, 95% CI: 1.4-3.0), smoked more than two heads per day (OR = 2.7, 95% CI: 1.8-4.0), had smoked for >20 years (OR = 1.9, 95% CI: 1.3-2.7), smoked more than 20 head-years (OR = 2.8, 95% CI: 1.9-4.1) and initiated smoking before the age of 30 years (OR = 1.7, 95% CI: 1.1-2.5). The association was only statistically significant for squamous cell carcinomas (OR = 1.8, 95% CI 1.2-2.7). Furthermore, this study observed a higher OR of lung cancer among exclusive waterpipe smokers (OR = 2.3, 95% CI: 1.6, 3.5). CONCLUSIONS: Waterpipe smoking was associated with an increased risk of lung cancer. The association was stronger with higher frequency, duration and intensity of exposure to waterpipe smoking. The association increases in exclusive waterpipe smokers, which is likely due to controlling for residual confounding by cigarette smoking and opium consumption, and higher exposure levels in this subpopulation.

Comparison of prognosis between hyperbilirubinemic infants with and without hypernatremia.

OBJECTIVES: Hypernatremia may facilitate the diffusion of bilirubin through the blood-brain barrier and increase the risk of bilirubin encephalopathy. This study was conducted to compare the prognosis of jaundice infants with those with jaundice and hypernatremia. METHODS: A total of 615 term infants with idiopathic jaundice with or without hypernatremia were enrolled in this cohort study with 24-months follow-up at Ghaem Hospital, Mashhad, Iran, between 2010 and 2022. An in-house questionnaire including the laboratory evaluation and neonatal characteristics was used as the data collection tool. The follow-up of neonatal development status was performed using the Denver test II at 6, 12, 18, and 24 months after discharging from hospital. RESULTS: Normal outcomes were seen in 555 (90.2%) out of 615 studied infants, while 60 cases (9.8%) showed abnormal outcomes. Serum levels of sodium (P = 0.017), bilirubin (P = 0.001), urea (P = 0.024), and creatinine (P = 0.011) as well as hyperthermia (P = 0.046) and unconsciousness (P = 0.005) showed significant differences between the two groups. Approximately 16% of the newborns with both jaundice and hypernatremia, and 9% of those with only jaundice had unfavorable prognoses. Also, bilirubin level had the most predictive power (91.3%). CONCLUSIONS: Our results suggest that hypernatremia or jaundice alone, may affect the prognosis of infants aged 2 years; but jaundice and hypernatremia together, will intensify the developmental problems in jaundice infants. However, the role of hyperbilirubinemia in the incidence of complications is more than hypernatremia.

Bac to Bac System Efficiency for Preparing HPV Type 16 Virus-Like Particle Vaccine.

Today, the human papillomavirus (HPV) L1 protein is the main target in the construction of prophylactic HPV vaccines. The production of virus-like particles (VLPs) that closely resemble the natural structure of the HPV16 virus and induce high levels of virus-neutralizing antibodies in animals and humans is facilitated by the expression of HPV16-L1 protein in eukaryotic cells. The Bac-to-Bac system has been previously used to produce high levels of recombinant proteins. In this study, we utilized this expression system to generate HPV16-L1 VLPs in Spodoptra frugipedra (Sf9) insect cells. The wild-type L1 gene of papillomavirus type 16 was selected from Gene Bank and placed in bacmid structure after codon optimization using pFast Bac vector. The recombinant baculovirus containing HPV-16/L1 gene was then provided using the Bac-to-Bac system. It should be mentioned that the vector was transfected into the Sf9 cell. The cells were then lysed and the expression of L1 protein was revealed by SDS-PAGE and confirmed by Western Blot. The L1 purification was performed through Ni-NTA chromatography. The VLP formation of papillomavirus L1 protein was visualized by transmission electron microscopy. The expressed recombinant L1 was ~60 KD on SDS-PAGE which was identified in western blot by a specific anti-L1 monoclonal antibody. The electron microscopy confirmed the assembly of VLPs. Results of this study showed that the production of this protein at the industrial level can be optimized using a baculovirus/Sf9 system. The characteristics and advantages of this system are promising and it is a suitable candidate for protein synthesis.

Erratum to "A Novel Method for Extraction of Galegine by Molecularly Imprinted Polymer (MIP) Technique Reinforced with Graphene Oxide and Its Evaluation Using Polarography".

[This corrects the article DOI: 10.1155/2020/3646712.].

A Novel Method for Extraction of Galegine by Molecularly Imprinted Polymer (MIP) Technique Reinforced with Graphene Oxide and Its Evaluation Using Polarography.

Galega officinalis products have been used for the control of diabetes (type 2) across the world. Experimental and clinical evaluations of galegine substance produced by a medicinal plant (Galega officinalis) provided the pharmacological and chemical basis for metformin discovery which was confirmed for diabetes therapy. In this paper, the molecularly imprinted polymer (MIP) was synthesized for galegine, using galegine as a template molecule, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, azobisisobutyronitrile (AIBN) as a reaction initiator, and acetonitrile as a solvent. The assisted functional groups, morphology, topographic image of surface, and crystalline structure of synthesized MIP were characterized by FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) images, and XRD diffraction pattern techniques, respectively. Also, the performance of the mentioned electrode was quantified and qualified by the differential pulse voltammetry technique (DPV). The galegine amount was determined with the polarographic technique. In this research, the galegine extraction conditions were optimized and graphene nanoparticles were used to increase the adsorption. In addition, different parameters affecting extraction were investigated such as MIP adsorbent amount, pH of solution, effect of the surfactant, and ionic compound to achieve high recovery percent. The recovery percent, limit of detection (LOD), limit of quantification (LOQ), and relative standard deviation (RSD %) were 4.101 µg·mL-1, 12.427 µg·mL-1, and 1.199% (n = 3), respectively. The results show that the prepared MIP can be used as an effective and inexpensive adsorbent for preconcentration and galegine extraction from a natural sample. It is noteworthy that this developed method was used successfully to determine galegine extracted from Galega officinalis L.

Effect of crude oil-induced water repellency on transport of Escherichia coli and bromide through repacked and physically-weathered soil columns.

Knowledge of the transport and fate of pathogenic Escherichia coli, especially in the areas contaminated with crude oil, is required to assess contamination of shallow groundwater resources. The present study aims to investigate the effect of crude oil-mediated water repellency on the movement of nalidixic acid-resistant Escherichia coli strain (E. coli NAR) and bromide (Br) as an inert tracer in two soil types. The soils were contaminated at three levels of 0, 0.5 and 1% w/w of total petroleum hydrocarbons (TPHs) using crude oil. Steady-state saturated flow in the soil columns was controlled using a tension infiltrometer. Leaching experiments were conducted through the columns of repacked (un-weathered) and physically-weathered clay loam (CL) and sandy loam (SL) soils. The columns leachate was sampled at specific times for 4 pore volumes. The shape of breakthrough curves for the E. coli NAR and Br depended on soil texture and structure and the TPHs level. Preferential flow in the crude oil-mediated water-repellent soils facilitated the transport of contaminants especially E. coli NAR. Filtration coefficient and relative adsorption index of bacteria were greatest in the repacked CL soils and were lowest in the weathered SL soils. Discontinuity of soil pores and lower flow velocity resulted in greater filtration of E. coli NAR in the repacked CL soil than other treatments. Physical weathering induced the formation of aggregates which reduced soil particle surfaces available for retention of water-repellent oil and contaminants. Movement of both bacteria and Br tracer in the weathered SL soil with 1% TPHs was higher than other treatments. This finding was attributed to low specific surface area, continuity of the pores and water repellency-mediated preferential pathways in the weathered SL soil columns. Our findings implied that shallow groundwater resources could be very sensitive to microbial contamination particularly in the oil-mediated water-repellent soils.

A systematic review and meta-analysis on the epidemiology, casual agents and demographic characteristics of onychomycosis in Iran.

Onychomycosis or fungal nail infection is one of the most common fungal infections. Nearly 50% of all nail disorders are caused by fungi. This systematic review and meta-analysis was conducted to determine the prevalence of onychomycosis across Iran. We searched English and Persian databases for studies reporting the epidemiologic features of onychomycosis in Iranian people from January 2000 to December 2018. Literature search revealed 307 studies, of which 24 studies met the eligibility criteria. In order to identifying the existence of publication bias among studies, funnel plots were used. The results of the meta-analysis were visualized as a forest plot representing the prevalence estimates of each study. Heterogeneity was also analyzed using the I2, Chi2, and Tau2 statistics. A high level of I2 and Chi2 was obtained among studies, which provides evidence of notable heterogeneity between studies. The results of current study revealed that the highest prevalence of onychomycosis was related to Mazandaran and Tehran provinces, respectively. As in the literature hypothesized shift in etiologic agents from yeasts to dermatophytes or molds could not be confirmed. Females were affected more frequently than males and in both sexes the highest incidence of infection occurrence was at the ages of >50 years. It seems the highest prevalence of onychomycosis in Mazandaran and Tehran provinces is due to the concentration of specialist doctors and research centers in these two provinces compared with others which leads to more detection and more care of the disease. Therefore, further educational strategies in order to accurate diagnosis in other provinces is necessary to reduce the risk of onychomycosis in Iran.

Correction to: Effects of dust on forest tree health in Zagros oak forests.

The original version of this article unfortunately contained an error in the affiliation section.

Evaluating the expression level of co-stimulatory molecules CD 80 and CD 86 in different types of colon polyps.

PURPOSE OF THE STUDY: Co-stimulatory molecules CD80 and CD86 are the members of B7 family, which stimulate the T lymphocytes in response to the malignant colon polyps. However, the expression of these molecules is depressed in cancers. In the present study, the transcription levels of CD80 and CD86 genes in the colon polyps (Precancerous lesions) and its association with the clinical features were examined. PATIENTS AND METHODS: Forty-nine biopsies samples from patients with the colorectal polyps and 10 healthy subjects were collected by the colonoscopy. Questionnaires including clinical and demographic data were filled for all cases. Using Real-time PCR, the mucosal mRNA expression levels of CD80 and CD86 genes were quantified. RESULTS: Adenoma and hyperplastic polyps were reported in 69.3 and 30.7 percent of 49 patients, respectively. Unlike hyperplastic polyps, the expression of CD86 was increased in adenoma polyps compared to controls (RQ=2.75 vs. 0.837, respectively). The data from CD80 showed noticeable reduction about 0.31 and 0.11 in adenoma and hyperplastic polyps, respectively, in response to control group (RQ=0.729). Also, analyzing colon and rectum polyps depicted a marked increment in CD86 level, in contrast to CD80. CONCLUSION: Examining the mRNA expression levels of CD80 and CD86 genes between colon polyps with the rectal polyps shows that the enhanced level of CD86 in adenoma samples could be considered as a valuable biomarker for distinguishing the adenoma from hyperplastic polyps and the masses located in the colon from the rectum.

Effects of dust on forest tree health in Zagros oak forests.

Dust is one of the most devastating factors for the environment threatening all animal and plant species. In many regions, the ecological and economic impact of microdust on scarce species is critical. In the western region of Iran, the Zagros forests have been exposed to dust storms for many years. In this study, the effect of dust on oak trees, the most important trees of Zagros forests, is investigated. For this purpose, 3-year-old seedlings of three species of oak trees under natural conditions were exposed to dust during spring and summer months. Seedlings were divided into two groups; one group was assigned as dust treatment and the other as control that the control group washed regularly to remove dust. Anatomical characteristics of leaves and dust deposits on leaves during the study period were examined by scanning electron microscope (SEM). The rate of photosynthesis and gas exchange in control and treated plants was examined by IRGA, LCI. SEM images showed that stomata structure, trichome density, and epicuticular waxes of leaves are different in all three species. This difference in micromorphology of species influences the effects of dust deposited on the leaves. A comparison of leaf species images in control and dust treatment showed that in dust treatment the percentage of stomata blocked by dust in three species (per unit area) of Quercus infectoria, Q. libni, and Q. brantii were 61/6, 48/4, and 38/1%, respectively. The results of leaf gas exchange investigation indicated that stomatal occlusion by dust had a negative impact on the examined parameters of three oak species (P ≤ 0.01). Thus, gas exchange and photosynthetic rates of the treated species were significantly reduced. The results of both parts of the study showed the vulnerability of the three species to dust as Q. infectoria > Q. libni > Q. brantii. Therefore, based on these findings, dust can disrupt the physiological activities of the studied species and the continuation of the exposure to dust will accelerate the process of destruction of these forests.

The evaluation of the effect of metformin on breast fibrocystic disease.

BACKGROUND: Fibrocystic changes (FCC) is the most common benign breast disease. The main pathophysiologic mechanism of FCC, excessive cell proliferation in response to monthly estrogen and progesterone changes. Regarding to antiproliferative of metformin, the aim of this study is the evaluation of the effect of metformin on FCC in women who were referred to gynecology clinics of ArakMETHODS:This study is a double blind placebo control randomized clinical trial. At the first among women who were referred to gynecology of Arak, 186 women with FCC between 18-40 years were selected. The women were randomly classified into three groups. The first group took metformin and the second group as placebo group took vitamin E and the third group did not take any drug during six months. All groups were compared in clinical symptoms based on visual analogue scale (VAS) and the sonographic data also were recorded and compared. Data analysis was performed by unilateral variance, student t and Chi-square. RESULTS: The three groups were not different in aspect of mean of the cysts number, cyst size, tenderness and discharge from breast before the intervention, but after the intervention, there was a significant decrease in metformin group (p value < 0.001) based on variance analysis test. There was not a meaningful difference of pain and the location of cysts between the groups after the intervention. CONCLUSIONS: The present study showed that metformin is effective in treatment of FCC and decreasing of clinical symptoms and imaging items.

A novel signaling role for miR-451 in esophageal tumor microenvironment and its contribution to tumor progression

Objective. We evaluated miR-451 expression in serum and tissue samples of esophageal squamous cell carcinoma (ESCC) patients. Then, we examined a secretory role of miR-451 in esophageal tumor microenvironment. Methods. miR-451 expression was evaluated in 39 serum samples from esophageal SCC patients compared to 39 normal individuals as well as 26 pairs of fresh-frozen tumor and adjacent normal tissues from patients with ESCC, using qRT-PCR. In a co-culture system of human normal fibroblasts (HFSF-PI3) and esophageal cancer cell line (KYSE-30), we evaluated exosomal miR-451 secretion into the conditioned medium (CM) of both cell lines. Then, we analyzed the effect of primiR-451-transfected fibroblasts on the migration potency of their neighboring KYSE-30 cells. Results. We detected miR-451 over-expression in serum samples of esophageal cancer patients compared to the normal group (P = 0.005). Interestingly, fresh-frozen tumor tissues from the same patients showed miR-451 down-regulation compared to their adjacent normal counterparts (P = 0.043). Co-culturing the KYSE-30 cell line with normal fibroblasts significantly induced miR-451 exosomal secretion into the CM. Moreover, co-culture of KYSE-30 cell line with miR-451-over-expressing fibroblasts significantly induced migration tendency in KYSE-30 cell line compared to the mock-transfected fibroblasts (P < 0.0001). In this system, MIF expression (a validated target of miR-451) in the KYSE-30 cell line was increased although this alteration was not statistically significant (fold change = 4.44). Conclusions. Our data suggest that cancer-associated fibroblasts use exosomal miR-451 as a signaling molecule to provide a favorable niche for tumor cell migration and cancer progression. Our findings provide new insights into the stromal role of miR-451 in the esophageal tumor microenvironment as a communicatory molecule and suggest a signaling role for miR-451 in extracellular matrix cross-talks (AU)

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A novel signaling role for miR-451 in esophageal tumor microenvironment and its contribution to tumor progression.

OBJECTIVE: We evaluated miR-451 expression in serum and tissue samples of esophageal squamous cell carcinoma (ESCC) patients. Then, we examined a secretory role of miR-451 in esophageal tumor microenvironment. METHODS: miR-451 expression was evaluated in 39 serum samples from esophageal SCC patients compared to 39 normal individuals as well as 26 pairs of fresh-frozen tumor and adjacent normal tissues from patients with ESCC, using qRT-PCR. In a co-culture system of human normal fibroblasts (HFSF-PI3) and esophageal cancer cell line (KYSE-30), we evaluated exosomal miR-451 secretion into the conditioned medium (CM) of both cell lines. Then, we analyzed the effect of primiR-451-transfected fibroblasts on the migration potency of their neighboring KYSE-30 cells. RESULTS: We detected miR-451 over-expression in serum samples of esophageal cancer patients compared to the normal group (P = 0.005). Interestingly, fresh-frozen tumor tissues from the same patients showed miR-451 down-regulation compared to their adjacent normal counterparts (P = 0.043). Co-culturing the KYSE-30 cell line with normal fibroblasts significantly induced miR-451 exosomal secretion into the CM. Moreover, co-culture of KYSE-30 cell line with miR-451-over-expressing fibroblasts significantly induced migration tendency in KYSE-30 cell line compared to the mock-transfected fibroblasts (P < 0.0001). In this system, MIF expression (a validated target of miR-451) in the KYSE-30 cell line was increased although this alteration was not statistically significant (fold change = 4.44). CONCLUSIONS: Our data suggest that cancer-associated fibroblasts use exosomal miR-451 as a signaling molecule to provide a favorable niche for tumor cell migration and cancer progression. Our findings provide new insights into the stromal role of miR-451 in the esophageal tumor microenvironment as a communicatory molecule and suggest a signaling role for miR-451 in extracellular matrix cross-talks.

Factors associated with subluxation in mallet fracture.

Radiographs and medical record of all adult patients with a mallet fracture in three hospitals between 2004 and 2014 were reviewed. International Classification of Diseases, Ninth Revision (ICD-9) codes and text search in radiographic reports were used to identify all acute patients with potential mallet fractures in our institutional database. Manually checking, 392 true mallet fractures were identified among them, 78 had subluxation at the time of diagnosis and 19 had subluxation at a later time point during treatment. Fragment size, fragment displacement, and interval between injury and treatment were associated with initial and late subluxation. Subluxation was not observed when the fracture size was less than 39% of the total articular surface. For each 1% increase in total articular surface involvement in fractures with more than 39% involvement, the risk of subluxation increased by 4% and for each 1% of displacement, the risk of subluxation increased by 4%. LEVEL OF EVIDENCE: IV.

Cryoprotectant-free vitrification of human spermatozoa in new artificial seminal fluid.

Vitrification is a new method that has been recently introduced in Assisted Reproduction Technique programs. The aim of this study was to design a new medium similar to normal human seminal fluid (SF), formulation artificial seminal fluid (ASF), and to compare the cryoprotective potency of this medium with SF and human tubal fluid (HTF) medium. Thirty normal ejaculates were processed with the swim-up technique and sperm suspensions were divided into four aliquots: (i) fresh sample (control); (ii) vitrification in HTF medium supplemented with 5 mg/mL human serum albumin and 0.25 mol sucrose (Vit HTF); (iii) vitrification with patients' SF (Vit SF); and (iv) vitrification in ASF (Vit ASF). After warming, sperm parameters of motility, viability, and morphology were analyzed using WHO criteria. Also, sperm pellets were fixed in 2.5% glutaraldehyde and processed for scanning electron microscopy and transmission electron microscopy observations. The results showed that progressive motility (46.09 ± 10.33 vs. 36.80 ± 13.75), grade A motility (36.59 ± 11.40 vs. 16.41 ± 11.24), and normal morphology (18.74 ± 8.35 vs. 11.85 ± 5.84) and viability (68.22 ± 10.83 vs. 60.86 ± 11.72) of spermatozoa were significantly higher in Vit ASF than in Vit HTF. All parameters were better in Vit ASF than in Vit SF, but only viability was significantly different (p = 0.006). After cryopreservation, deep invagination in cytoplasm and mechanically weak point sites and folded tail were commonly observed. But, this phenomenon was more significant in Vit HTF and Vit SF than in ASF (p < 0.05). In transmission electron microscopy evaluation, acrosome damage, plasma membrane loss, chromatin vacuolation, and disruption of mitochondria arrangement and structures were observed in all vitrified groups. Adherence of several tail sections together was also seen in all cryo groups. But this was seen more in Vit HTF and Vit SF than in ASF (p < 0.05). In conclusion, vitrification of human spermatozoa with ASF can effectively preserve the quality of sperm motility in comparison with Vit HTF.

Synthesis, characterization and biological evaluation of novel α, ß unsaturated amides.

Three derivatives of α,ß unsaturated amides have been successfully synthesized via Ugi-four component (U-4CR) reaction. The interactions of the amides with calf thymus deoxyribonucleic acid (ct-DNA) have been investigated in the Tris-HCl buffer (pH=7.4) using viscometric, spectroscopic, thermal denaturation studies, and also molecular docking. By UV-Vis absorption spectroscopy studies, adding CT-DNA to the compound solution caused the hypochromism indicates that there are interactions between the compounds and DNA base pairs. In competitive fluorescence with methylene blue as an intercalator probe, adding compounds to DNA-MB solution caused an increase in emission spectra of the complex. This could be because of compound replacing, with similar binding mode of MB, between the DNA base pairs due to release of bonded MB molecules from DNA-MB complex. Thermal denaturation studies and viscometric experiments also indicated that all three investigated compounds bind to CT-DNA by non-classical intercalation mode. Additionally, molecular docking technique predicted partial intercalation binding mode for the compounds. Also, the highest binding energy was obtained for compound 5a. These results are in agreement with results obtained by empirical methods.

Carbon-Nanohorn Based Nanofluids for a Direct Absorption Solar Collector for Civil Application.

Direct solar absorption has been often considered in the past as a possible solution for solar thermal collectors for residential and small commercial applications. A direct absorption could indeed improve the performance of solar collectors by skipping one step of the heat transfer mechanism in standard devices and having a more convenient temperature distribution inside the collector. Classical solar thermal collectors have a metal sheet as absorber, designed such that water has the minimum temperature in each transversal section, in order to collect as much solar thermal energy as possible. On the other hand, in a direct configuration, the hottest part of the system is the operating fluid and this allows to have a more efficient conversion. Nanofluids, i.e., fluids with a suspension of nanoparticles, such as carbon nanohorns, could be a good and innovative family of absorbing fluids owing to their higher absorption coefficient compared to the base fluid and stability under moderate temperature gradients. Moreover, carbon nanohorns offer the remarkable advantage of a reduced toxicity over other carbon nanoparticles. In this work, a three-dimensional model of the absorption phenomena in nanofluids within a cylindrical tube is coupled with a computational fluid dynamics (CFD) analysis of the flow and temperature field. Measured optical properties of nanofluids at different concentrations have been implemented in the model. Heat losses due to conduction, convection and radiation at the boundaries are considered as well.

Pattern of mandibular third molar impaction: A cross-sectional study in northeast of Iran.

OBJECTIVES: Impacted teeth, if left untreated, have a potential to induce various complications. The aim of the current study was to determine the prevalence and pattern of impacted mandibular third molar in the Iranian population. STUDY DESIGN: This cross-sectional study was performed in patients who were referred to the Department of Oral Radiology between July 2009 and October 2010 to obtain an orthopantomogram (OPG). Data were collected regarding age and gender, prevalence of impacted mandibular third molars, angulation of impacted teeth (Winter's classification), level of impaction (Pell and Gregory classification), and relationship of the mandibular third molar with the ramus (Pell and Gregory classification). The collected data were analyzed using SPSS software version 11.0 with a confidence interval of 95%. RESULTS: Among the 1433 patients included in the study, 489 (34.12%) patients were male and 944 (65.88%) were female. Of the total OPGs performed, 871 (60.78%) OPGs demonstrated at least one impacted mandibular third molar. In addition, of the 2866 mandibular third molars investigated, 1397 (48.74%) were found to be impacted. A significant association was observed between gender and the number of impacted teeth or the presence of impaction of any mandibular tooth (or teeth) (P < 0.05). The most common type of tooth angulation was mesioangular (48.67%). In addition, the most prevalent type of impaction level and ramus relationship was level B (63.85%) and Class II (48.46%), respectively. There were no significant differences between the two sides of the mandible for the prevalence of impacted third molar (P > 0.05). CONCLUSION: The pattern of mandibular third molars in the Northeast region of Iran revealed a high prevalence of impaction, which was mostly mesioangular, level B, and Class II with a gender predilection for females.