Sensitive colorimetric assay using insulin G-quadruplex aptamer arrays on DNA nanotubes coupled with magnetic nanoparticles.

Described here is a methodology for fabrication of a sensitive colorimetric nanoassay for measurement of insulin using G-quadruplex aptamer arrays on DNA nanotubes (DNTs) coupled with magnetic nanoparticles. The spectroscopic findings (e.g. visible spectra, velocity assay and limit of detection determination) indicated a highly sensitive performance of this new nanoassay in comparison to those results obtained from the insulin assay with non-arrayed aptamers. The clinical performance statistics (i.e. paired sample t-test, Bland-Altman plot and scatter diagram) from the newly developed assay and the enzyme-linked immunosorbent assay suggested its reliable precision and its acceptable repeatability for measurement of insulin in human sera. This is, to our knowledge, the first study for the application of magnetic nanoparticle-coupled DNTs for carrying G-quadruplex aptamers for detection of biomolecules (such as insulin) in human serum.

Predictors of survival in oesophageal cancer patients in a high-risk area in Northern Iran: the role of health services utilisation.

We aimed to determine predictors of survival in oesophageal cancer (EC) patients in a high-risk area. This study was conducted on EC patients diagnosed in 2007-2008 in Golestan province, Iran. Diagnostic (DU) and Therapeutic (TU) services utilisation indices were determined. DU and TU indices of 1 were considered as good utilisation. EC-specific survival rates were calculated. Multivariate Cox-regression model was used to calculate adjusted hazard ratios (AHRs). Two hundred and twenty-three EC subjects were enrolled. The median survival time was 10.47 months and the 5-year survival rate was 11%. Cox-regression analysis suggested that stage of tumour (AHRregional  = 3.75, 95% confidence interval [CI]: 2.34-6.00; AHRmetastasis  = 12.21, 95% CI: 7.42-20.08) and TU (AHR = 1.78, 95% CI: 1.25-2.52) were the strongest variables related to EC survival. The median survival time in patients with good and poor TU were 14.37 and 8.53 months respectively (p < .01). There was no significant relationship between DU and EC survival. We found relatively low survival rates in our EC patients when compared with developed countries. Our results also suggested an increasing trend for EC survival rate during recent years. Good TU could predict higher survival rates. Patients' access to therapeutic services may be considered as an important indicator in decision-making for controlling EC.

Selenium Supplementation Affects Insulin Resistance and Serum hs-CRP in Patients with Type 2 Diabetes and Coronary Heart Disease.

To our knowledge, this study is the first indicating the effects of selenium supplementation on metabolic status of patients with type 2 diabetes mellitus (T2DM) and coronary heart disease (CHD). This study was conducted to evaluate the effects of selenium supplementation on metabolic profiles, biomarkers of inflammation, and oxidative stress of patients with T2DM and CHD. This randomized, double-blind, placebo-controlled trial was performed among 60 patients with T2DM and CHD aged 40-85 years. Participants were randomly divided into 2 groups. Group A received 200 µg selenium supplements (n=30) and group B received placebo per day (n=30) for 8 weeks. Fasting blood samples were taken at the beginning of the study and after 8-week intervention to quantify metabolic profiles. After 8 weeks, compared with the placebo, selenium supplementation resulted in a significant decrease in serum insulin levels (- 2.2±4.6 vs. + 3.6±8.4 µIU/ml, p=0.001), homeostasis model of assessment-insulin resistance (HOMA-IR) (- 0.7±1.3 vs. + 0.9±2.4, p=0.004), homeostatic model assessment-beta cell function (HOMA-B) (- 7.5±17.2 vs. + 15.1±34.5, p=0.002) and a significant increase in quantitative insulin sensitivity check index (QUICKI) (+0.01±0.03 vs. - 0.01±0.03, p=0.02). In addition, patients who received selenium supplements had a significant reduction in serum high-sensitivity C-reactive protein (hs-CRP) (- 1 372.3±2 318.8 vs. - 99.8±1 453.6 ng/ml, p=0.01) and a significant rise in plasma total antioxidant capacity (TAC) concentrations (+ 301.3±400.6 vs. - 127.2±428.0 mmol/l, p<0.001) compared with the placebo. A 200 µg/day selenium supplementation among patients with T2DM and CHD resulted in a significant decrease in insulin, HOMA-IR, HOMA-B, serum hs-CRP, and a significant increase in QUICKI score and TAC concentrations.

Susceptibility status of field populations of Rhipicephalus bursa (Acari: Ixodidae) to pyrethroid insecticides.

Rhipicephalus bursa is a two-host ixodid tick with wide distribution in north of Iran especially in Mazandaran province. Acaricide treatment is the main tick control measure; however, acaricide resistance occurs in hard ticks in many areas of the world including Iran. Comprehensive information on susceptibility status of Rhipicephalus bursa is lacking, therefore, this study is undertaken to determine the susceptibility status of the species to pyrethroid acaricides and probable biochemical underlying mechanisms of resistance. From May 2013 to March 2014, engorged females Rhipicephalus bursa were collected using standard entomological procedures from body surface of sheep, goat and cattle in different areas of Mazandaran province, northern Iran. Eleven and ten pooled tick populations were tested against cypermethrin and lambda-cyhalothrin, respectively using larval packet test. Population SC-16 showed a maximum resistance ratio of 5.79 against cypermethrin in Sari County when compared to the most susceptible population NH-16 and 63.64% of tick populations were resistant at LC99 level. With lambda-cyhalothrin, 30% of the tick populations were resistant with low level and NK-2 was the most resistant population with resistance ratio of 4.32 in Nowshahr County. The results of biochemical assays demonstrated elevated levels of monooxygenases, glutathione S-transferases and esterases in pyrethroid resistant populations tested.

Cognitive deficit in first-time coronary artery bypass graft patients: a randomized clinical trial of lidocaine versus procaine hydrochloride.

INTRODUCTION: Cognitive dysfunction increasingly has been recognized as a complication after cardiac surgery. Different methods have been considered for the reduction of cognitive dysfunction after cardiac surgery. One of these methods is by using lidocaine during surgery. The aim of this study was to determine the effects of adding lidocaine to the cardioplegia solution on cognitive impairment after coronary artery surgery. DESIGN AND METHODS: In a prospective, randomized, double-blind trial, 110 patients aged between 20-70 years, scheduled for elective CABG surgery using cardiopulmonary bypass, were recruited into the study. They were randomized into two groups who received either cardioplegia solution containing lidocaine 2 mg/kg or procaine hydrochloride 5 mg/kg. The neurocognitive test used in this study was the Mini Mental State Examination (MMSE) or Folstein test. The test was done on the day before and 10 days and 2 months after the operation. RESULTS: In the procaine group, the total score after 10 days decreased significantly compared to the preoperative score (mean difference 0.68; 95% CI: 0.20 to 1.17, p=0.006). Comparison between mean differences after 10 and 60 days of operation between the lidocaine and procaine groups were statistically significant, p-value 0.017 and 0.013, respectively. There was no cognitive impairment in the lidocaine group, but, in the procaine group, four patients (7.7%) after 10 days and one patient (1.9%) after both 10 and 60 days had cognitive impairment, p=0.051. CONCLUSIONS: Administration of lidocaine compared to that of procaine through the cardioplegia solution had a better effect on cognitive function after coronary artery bypass graft surgery.

To study various concentrations of magnesium and aluminium on amylin hormone conformation.

Type 2 diabetes mellitus can be defined as a conformational disease since a beta cell producing protein called amylin undergoes a change in the tertiary structure followed by self-aggregation and deposition. Amylin deposition causes destruction of pancreatic beta-cells. The aim of this study was to investigate whether different concentrations of magnesium and aluminium alter amylin conformation under near-physiological circumstances. Conformational variations were monitored by fluorescent method before and after incubation by shaker incubator in 37 degrees C by LS55 spectrofluorometer instrument. This in vitro study showed that magnesium had contradictory effects on amylin folding and these effects were magnesium concentration dependent. Magnesium with concentration of 1 to 1.5 mM had inhibitory effect but in 2.5 to 3.5 microM promoted amylin misfolding significantly (p < 0.05). The obtained data also demonstrated that aluminium with concentrations of 5, 10 and 20 microM had stimulatory effects on formation of beta-amyloid sheet significantly (p < 0.05). It may be concluded that islet amyloid misfolding and cytotoxicity to beta-cells might be magnesium dose dependent in diabetic patients.

Association of TGIFLX/Y mRNA expression with azoospermia in infertile men.

HOX genes are well-known to encode transcriptional regulatory proteins that play essential roles in directing embryonic development. TGIFLX/Y contains two genes, TGIFLX (X-linked) and TGIFLY (Y-linked), which are specifically expressed in human adult testes. The function(s) of these genes in normal and abnormal development are unknown. To investigate the potential role(s) of the TGIFLX/Y gene in infertile males, a nested reverse transcriptase polymerase chain reaction (RT-PCR) was performed on testicular samples from 110 patients with nonobstructive azoospermia. Although the only 51 (46.4%) of the 110 patients had detectable levels of TGIFLY expression, none of the patients with various spermatogenesis defects showed any of the TGIFLX gene expression found in normal testes. These results suggest that the function of TGIFLX may be required for the regulation of spermatogonial stem cell specification and proliferation. While functional similarity has been demonstrated among some homeobox genes, these results may refute the suggestion of redundancy between TGIFLX and TGIFLY. Furthermore, TGIFLX might be a potential biomarker candidate for male infertility assessment.