Preparation and characterization of hydrogel nanocomposite based on nanocellulose and acrylic acid in the presence of urea.

In this study, acrylic acid (AA) and cellulose nanofibers (CNFs) were used as main materials to synthesize an acrylic-nanocellulose hybrid hydrogel nanocomposite in the presence of urea. The interpenetrating polymer networks were obtained by radical polymerization in different urea: AA ratios (0:10, 1:10, 3:10, 5:10, 10:10). Fourier transform infrared spectroscopy (FTIR) combined with X-ray diffraction (XRD) and elemental analysis techniques confirmed the chemical interaction of urea in the network structure. Free absorption and water absorption under load (AUL) of the synthesized hydrogels varying in urea: acrylic acid weight ratios were measured in distilled water and saline (0.9 wt%) solution for hybrid (5 wt% CNFs) and pure polyacrylic acid (0 wt% CNFs) hydrogels. It was found that incorporation of urea and CNFs in the hybrid structure generating compact hydrogel networks with high crosslink density leading to lower absorption with and without pressure, whereas incorporation of urea in the structure resulted in a more extended network with higher absorption capacity (about 3×) than hybrid structure.

A novel ECG criterion to differentiate left from right ventricular outflow tract premature complex.

Objectives. Catheter ablation is an effective method in the treatment of idiopathic ventricular arrhythmias. The mapping methods used for predicting the original site of arrhythmias are difficult to use and time-consuming. Consequently, developing methods using surface ECG for guiding the location is important. Here, we have tested a new ECG criterion to differentiate the left from the right ventricular originated complexes (PVCs) or tachycardias (VTs). Designs. Sixty patients with idiopathic PVC or VT who had undergone a successful radiofrequency catheter ablation (RFA) of arrhythmia were enrolled. The surface ECG during sinus rhythm and arrhythmia was analyzed. Initial r wave Surface Area (ISA) index was measured by multiplying the R wave duration in milliseconds by the R wave amplitude in terms of millivolt in V1 or V2 leads. Results. Thirty-seven patients with right ventricular (RVOT) and 23 with left ventricular outflow tract (LVOT) originated VT or PVC were enrolled. The ISA index was significantly greater in LVOT-VT/PVC compared to RVOTs (63.6 ± 78.9 vs. 8.3 ± 7.3, p < .001). With a cut off value of ≥15, the index could differentiate a left from right arrhythmia with 94.6% specificity and 78.2% sensitivity (Area on the curve, 0.81; p < .001). Compared to other previously reported indices, ISA is the most specific one. Conclusion. ISA index can serve as a very useful ECG criterion for differentiating a LVOT- from RVOT-originated VTs or PVCs.

Sub-lethal effects of dimethoate alone and in combination with cadmium on biochemical parameters in freshwater snail, Galba truncatula.

The objective of the present study was to evaluate the influence of the organophosphorus pesticide dimethoate and cadmium on biochemical parameters of a freshwater snail, Galba truncatula, in laboratory conditions. In 14 days, snails were exposed to 0, 100, 200, and 400 µg L-1 of dimethoate and 0.0 and 1000 µg L-1 of cadmium chloride. The results evidenced that dimethoate induces oxidative stress and alters biochemical parameters in freshwater snails. Cadmium also induced significant changes in biochemical parameters. The combination of the dimethoate and cadmium markedly increased the effects on G. truncatula. Dimethoate and cadmium mixture caused a decrease in Acetylcholinesterase (AChE), and Glucose-6-phosphate dehydrogenase (G6PDH) activities, glycogen, and total antioxidant capacity (TAN) levels, and increased aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutathione peroxidase (GPx), and catalase (CAT) activities, and malondialdehyde (MDA) level in exposed snails. The increased toxicity and bioaccumulation of cadmium after the exposure to the highest concentration of dimethoate indicates a synergistic effect leading to a reduced performance of the detoxification system in the snail. Dimethoate contributed to the bioconcentration of cadmium in snails and increased its toxic effects evidenced in biomarkers of oxidative stress and cell damage.

Epidemiology of cervical cancer and human papilloma virus infection among Iranian women - analyses of national data and systematic review of the literature.

BACKGROUND: Few studies have evaluated the epidemiology of cervical cancer in low risk Muslim countries, where the prognosis of cervical cancer is poor and which lack an organized cervical screening program. We studied incidence and mortality rates of cervical cancer and the prevalence of high risk human papilloma virus (HPV) infection in the Islamic Republic (I.R.) of Iran. METHODS: We analyzed national cancer and mortality registration data and estimated age-standardized incidence (ASR) and mortality (ASMR) rates and age-specific patterns of cervical cancer. Furthermore, based on a systematic review we estimated prevalence of HPV infection in Iran. RESULTS: The mean cervical cancer ASR was 2.5 per 100,000 in pathology-based cancer registries. However, ASRs were almost double in the population-based cancer registry and reached 6 per 100,000. The mean cervical cancer ASMR for Iran was 1.04 per 100,000. The mortality to incidence ratio was 42%. The cervical cancer incidence rate increased after age 30 and peaked between ages 55 and 65. The prevalence of HPV infection was 76% in cervical cancer patients and 7% among healthy Iranian women. Of the HPV types isolated, HPV 16 (54%), 18 (14%), and 31 (6%) were the most commonly detected in Iranian cervical cancer patients. CONCLUSIONS: An organized prevention program is needed to fight against cervical cancer in Iran and other low incidence countries. We suggest a screening program starting after age 30 and with at least three screenings tests over each woman's lifetime. With a reservation on cost-effectiveness issue, available HPV vaccine will prevent HPV infection and cervical cancer in Iran.