A novel fabrication of a high performance SiO(2)-graphene oxide (GO) nanohybrids: Characterization of thermal properties of epoxy nanocomposites filled with SiO(2)-GO nanohybrids.

In this study it has been aimed to enhance the thermal resistance of epoxy coating through incorporation of SiO2-GO nanohybrids. SiO2-GO nanohybrids were synthesized through one-step sol-gel route using a mixture of Tetraethylorthosilane (TEOS) and 3-Aminopropyl triethoxysilane (APTES) silanes. The SiO2-GO nanohybrids were prepared at various hydrolysis times of 24, 48 and 72h. Then 0.2wt.% of GO and SiO2-GO nanohybrids were separately incorporated into the epoxy coating. Results revealed that amino functionalized SiO2 nanoparticles with particle size around 20-30nm successfully synthesized on the basal plane of GO. Results showed significant improvement of dispersion and interfacial interactions between nanohybrids and epoxy composite arising from covalent bonding between the SiO2-GO and the epoxy matrix. It was found that the thermal resistance of SiO2-GO nanohybrids and SiO2-GO/Epoxy nanocomposite was noticeably higher than GO and epoxy matrix, respectively.

Carnosine mitigates apoptosis and protects testicular seminiferous tubules from gamma-radiation-induced injury in mice.

This study investigated the radioprotective effects of a naturally occurring dipeptide, carnosine, on testicular damage. Carnosine was administered (10, 50 and 100 mg kg(-1) body weight) to male mice via intraperitoneal injection for 4 days prior to gamma irradiation (2 Gy). Apoptosis with the TUNEL assay and histopathological parameters were evaluated 12-h and 14-day post-irradiation. Pre-treatment with carnosine before irradiation significantly reduced the frequency of TUNEL-positive cells induced by radiation treatment at all doses by reduction factors of 1.8, 2.47 and 2.23 for carnosine at 10, 50 and 100 mg kg(-1) bw, respectively, unlike that observed in the radiation alone group. Exposure to ionising radiation decreased sperm count and reduced the height and diameter of seminiferous epithelial tubules. Pre-treatment with all doses of carnosine significantly augmented seminiferous epithelial height and tubule diameter and also increased the number of germinal cells in comparison to the group treated with radiation only. These results indicate that carnosine prevents testicular dysfunction induced by gamma-irradiation via an anti-apoptotic effect; this restoration of proper testicular function ultimately leads to the recovery of spermatogenesis.

Fetal lung volume and quantification of liver herniation by magnetic resonance imaging in isolated congenital diaphragmatic hernia.

OBJECTIVE: To determine associations between fetal lung and liver herniation volumes measured by magnetic resonance imaging (MRI) and mortality/need for extracorporeal membrane oxygenation (ECMO) in cases of isolated congenital diaphragmatic hernia (CDH). A secondary objective was to compare prenatal MRI parameters with two-dimensional ultrasound lung measurements. METHODS: A retrospective review of medical records of all fetuses with isolated CDH evaluated between January 2004 and July 2012 was performed. The following MRI parameters were measured at 20-32 weeks: observed/expected total fetal lung volume (o/e-TLV), predicted pulmonary volume (PPV), percentage of liver herniated into the fetal thorax (%LH) and the liver/thoracic volume ratio (LiTR). These were compared with the ultrasound-determined lung-to-head ratio (LHR) and the observed/expected LHR (o/e-LHR) in the same cohort. The predictive value of MRI and ultrasound parameters for mortality and the need for ECMO was evaluated by univariate, multivariate and factor analysis and by receiver-operating characteristics curves. RESULTS: Eighty fetuses with isolated CDH were evaluated. Overall mortality was 18/80 (22.5%). Two newborns died a few hours after birth. ECMO was performed in 29/78 (37.2%) newborns, with a survival rate of 48.3% (14/29). The side of the diaphragmatic defect was not associated with mortality (P = 0.99) or the need for ECMO (P = 0.48). Good correlation was observed among o/e-TLV, PPV, LHR and o/e-LHR as well as between %LH and LiTR (r = 0.89; P < 0.01); however, fetal lung measurements and measures of liver herniation were not correlated (all P > 0.05). All parameters were statistically associated with mortality or the need for ECMO. The best combination of measurements to predict mortality was o/e-TLV and %LH, with 83% accuracy. CONCLUSION: Mortality and the need for ECMO in neonates with isolated CDH can be best predicted using a combination of MRI o/e-TLV and %LH.

Perinatal outcome after fetoscopic release of amniotic bands: a single-center experience and review of the literature.

OBJECTIVES: To present two successful cases of fetoscopic release of amniotic bands with umbilical cord involvement and provide a review of the literature on fetal intervention for amniotic band syndrome (ABS). METHODS: Two cases of ABS were considered in conjunction with a review of the literature. A total of 14 fetuses with ABS underwent fetoscopic intervention between 1965 and 2012. Two of the authors independently completed literature searches in PubMed, Ovid and MEDLINE for articles related to ABS. RESULTS: Among 14 cases of ABS (12 published and our own two), 57% and 7% were complicated by preterm premature rupture of membranes and spontaneous preterm birth, respectively. Overall, fetoscopic intervention preserved limb function in 50% (7/14) of cases. Three cases involved intraoperative complications including intra-amniotic bleeding and uterine wall bleeding, and incomplete procedure due to ineffective equipment. CONCLUSION: Fetoscopic release of amniotic bands with minimally invasive surgery may allow preservation of life and/or limb function in cases of ABS. The acceptable functional outcome in 50% of cases is reassuring, although more experience and further studies are needed to determine the selection criteria that will justify the risk of this invasive in-utero therapy for ABS.

Fetoscopic laser ablation of placental anastomoses in twin-twin transfusion syndrome using 'Solomon technique'.

OBJECTIVE: To document perinatal outcomes following use of the 'Solomon technique' in the selective photocoagulation of placental anastomoses for severe twin-twin transfusion syndrome (TTTS). METHODS: Between January 2010 and July 2012, data were collected from 102 consecutive monochorionic twin pregnancies complicated by severe TTTS that underwent fetoscopic laser ablation at four different centers. We compared outcomes between subjects that underwent selective laser coagulation using the Solomon technique (cases) and those that underwent selective laser coagulation without this procedure (controls). RESULTS: Of the 102 pregnancies examined, 26 (25.5%) underwent the Solomon technique and 76 (74.5%) did not. Of the 204 fetuses, 139 (68.1%) survived up to 30 days of age. At least one twin survived in 82 (80.4%) pregnancies and both twins survived in 57 (55.9%) pregnancies. When compared with the control group, the Solomon-technique group had a significantly higher survival rate for both twins (84.6 vs 46.1%; P < 0.01) and a higher overall neonatal survival rate (45/52 (86.5%) vs 94/152 (61.8%); P < 0.01). Use of the Solomon technique remained independently associated with dual twin survival (adjusted odds ratio (aOR), 11.35 (95% CI, 3.11-53.14); P = 0.0007) and overall neonatal survival rate (aOR, 4.65 (95% CI, 1.59-13.62); P = 0.005) on multivariable analysis. There were no cases of recurrent TTTS or twin anemia-polycythemia sequence (TAPS) in the Solomon-technique group. CONCLUSIONS: Use of the Solomon technique following selective laser coagulation of placental anastomoses appears to improve twin survival and may reduce the risk of recurrent TTTS and TAPS. Our data support the idea of performing a randomized controlled trial to evaluate the effectiveness of the Solomon technique.

Estimating risk factors and causes for postpartum febrile morbidity in teenage mothers.

In this cohort study, our objective was to identify potentially modifiable risk factors and causes for febrile morbidity in teenage mothers. We identified all cases of febrile morbidity using the United States Joint Commission on Maternal Welfare definition in a cohort of teenage deliveries over a 4-year period at one institution. Of the 730 included teenage deliveries, 49 (7%) women suffered postpartum febrile morbidity. Higher maternal pre-pregnancy body mass index (BMI: 34.0 ± 8.6 vs 30.3 ± 6.0 kg/m(2), p = 0.0001), caesarean delivery (RR 21.3, 95% CU 8.9-54.9) and postpartum haemorrhage (RR 3.0, 95% CI 1.1-6.7) were associated with postpartum febrile morbidity. Risk factors for febrile morbidity in the teenage parturient include obesity, caesarean delivery and postpartum haemorrhage. Considering the increasing rates of teenage obesity and overall caesarean delivery rates, attention must be focused on these modifiable risk factors to avoid this complication during a tenuous time for the teenage parent.

The radioprotective effects of Origanum vulgare extract against genotoxicity induced by (131)I in human blood lymphocyte.

Radioiodine ((131)I) has been widely used for the treatment of patients with thyroid diseases. However, there is a persisting concern about the induction of second tumor and genetic damage after (131)I therapy. The purpose of this study was to investigate the radioprotective effects of Origanum vulgare extract against genotoxicity induced by (131)I in human lymphocytes. Whole blood samples from human volunteers were incubated with origanum extract at doses of 12.5, 25, 50 and 100 µg/mL. After 1 hour of incubation, the lymphocytes were incubated with (131)I (20 µCi/mL) for 1 hour. The lymphocytes were then cultured with a mitogenic stimulant to evaluate micronucleus formation in cytokinesis-blocked binucleated cells. Incubation of lymphocytes with (131)I induced additional genotoxicity and shown by increases in micronuclei (MN) frequency in human lymphocytes. Origanum at three last doses significantly reduced the MN frequency in cultured lymphocytes. The maximum protective effect and the maximum decrease in the frequency of MN were observed at 100 µg/mL of origanum, which caused a reduction of 70% (p<0.0001). Origanum extract also exhibited an excellent and dose-dependent radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl-free radicals. This study has important implications for patients undergoing nuclear medicine procedures. The results indicate a protective role for origanum extract against the genetic damage induced by radiopharmaceutical administration.

Chromosome aberrations in peripheral blood lymphocytes of individuals living in high background radiation areas of Ramsar, Iran.

In order to investigate the biological effects of exposure to low-dose radiation and to assess the dose-effect relationship in residents of high background radiation areas (HBRAs) of Ramsar, cytogenetic investigation of unstable-type aberrations was performed in 15 healthy elderly women in a HBRA of Ramsar, Talesh mahalle, and in 10 elderly women living in a nearby control area with normal background radiation. In total, 77,714 cells were analyzed; 48,819 cells in HBRA residents and 28,895 cells in controls. On average, 3,108 cells per subject were analyzed (range 1,475-5,007 cells). Significant differences were found in the frequency of dicentric plus centric rings in 100 cells (0.207 ± 0.103 vs. 0.047 ± 0.027, p < 0.0005), total chromosome-type aberrations per 100 cells (0.86 ± 0.44 vs. 0.23 ± 0.17, p < 0.0005), and chromatid-type aberrations per 100 cells (3.31 ± 2.01 vs. 1.66 ± 0.63, p = 0.01) by the Mann-Whitney U test between HBRA and the control, respectively. Using chromosomal aberrations as the main endpoint to assess the dose-effect relationship in residents of HBRAs in Ramsar, no positive correlation was found between the frequency of dicentric plus centric ring aberrations and the cumulative dose of the inhabitants estimated by direct individual dosimetry; however, obvious trends of increase with age appeared in the control group. Based on these results, individuals residing in HBRAs of Ramsar have an increased frequency of detectable abnormalities in unstable aberrations.

In vivo gamma-rays induced initial DNA damage and the effect of famotidine in mouse leukocytes as assayed by the alkaline comet assay.

Ionizing radiation induces a variety of lesions in DNA, each of which can be used as a bio-indicator for biological dosimetry or the study of the radioprotective effects of substances. To assess gamma ray-induced DNA damage in vivo in mouse leukocytes at various doses and the effect of famotidine, blood was collected from Balb/c male mice after irradiation with 4 Gy gamma-rays at different time intervals post-irradiation. To assess the response, mice were irradiated with doses of gamma-rays at 1 to 4 Grays. Famotidine was injected intra-peritoneally (i.p) at a dose of 5 mg/kg at various time intervals before irradiation. Four slides were prepared from each sample and alkaline comet assay was performed using standard protocols. Results obtained show that radiation significantly increases DNA damage in leukocytes in a dose dependent manner (p < 0.01) when using appropriate sampling time after irradiation, because increasing sampling time after irradiation resulted in a time dependent disappearance of DNA damage. Treatment with only 5 mg/kg famotidine before 4 Gy irradiation led to almost 50% reduction in DNA damage when compared with those animals which received radiation alone. The radioprotective capability of famotidine might be attributed to radical scavenging properties and an anti-oxidation mechanism.

Cytogenetic radiosensitivity of g0-lymphocytes of breast and esophageal cancer patients as determined by micronucleus assay.

Enhanced chromosomal radiosensitivity is a feature of many cancer predisposition conditions, indicative of the important role of chromosomal alterations in carcinogenesis. In this study the cytokinesis-blocked micronucleous assay was used to compare the radiosensitivity of blood lymphocytes obtained from Iranian breast or esophageal cancer patients (n = 50, n = 16; respectively) with that of control individuals (n = 40). For each sample, one thousand binucleate lymphocytes were analyzed before and after in vitro exposure to 3 Gy of gamma rays. The radiation-induced frequency of micronucleus was significantly higher in the breast cancer group (261/1,000 binucleated cells) than in esophageal cancer group (241/1,000 binucleated cells, P < 0.01) or in the control group (240/1,000 binucleated cells, P < 0.01). The results indicate that breast cancer patients are more radiosensitive compared to normal healthy individuals or esophageal cancer patients. Increased radiosensitivity could be due to defects in DNA repair genes involved in breast cancer formation. Since patients with esophageal cancer did not show elevated radiosensitivity, it is assumed that the contribution of radiosensitivity-related genes to the development of esophageal cancer may be smaller than the contribution of those genes to breast cancer.

Temporal stability of acute stressor-induced changes in cellular immunity.

This study examined the temporal stability of enumerative immune responses to acute psychosocial stress. Lymphocyte subsets were measured in 24 healthy male subjects at rest and following a speaking stressor on two occasions approximately six weeks apart. The speaking task caused significant increases in T-suppressor/cytotoxic cells, natural killer cells, T-cells, and total WBC and decreases in the T-helper/suppressor ratio. Baseline test-retest correlation's were statistically significant for all variables (r values = 0.40-0.90). With two exceptions (T-cells and T-suppressor/cytotoxic cells), speaking task values (absolute reactivity scores) were also statistically significant (r values = 0.48-0.92). Baseline adjusted test-retest correlations were however generally less reliable, with only natural killer cells (r values > 0.40), the T-helper/suppressor ratio (r = 0.60), and total WBC (r = 0.48) showing statistical significance. The findings suggest that certain but not all cellular immune responses to acute stress are moderately stable over time.