Multidimensional Mapping Method Using an Arrayed Sensing System for Cross-Reactivity Screening

When measuring chemical information in biological fluids, challenges of cross-reactivity arise, especially in sensing applications where no biological recognition elements exist. An understanding of the cross-reactions involved in these complex matrices is necessary to guide the design of appropriate sensing systems. This work presents a methodology for investigating cross-reactions in complex fluids. First, a systematic screening of matrix components is demonstrated in buffer-based solutions. Second, to account for the effect of the simultaneous presence of these species in complex samples, the responses of buffer-based simulated mixtures of these species were characterized using an arrayed sensing system. We demonstrate that the sensor array, consisting of electrochemical sensors with varying input parameters, generated differential responses that provide synergistic information of sample. By mapping the sensing array response onto multidimensional heat maps, characteristic signatures were compared across sensors in the array and across different matrices. Lastly, the arrayed sensing system was applied to complex biological samples to discern and match characteristic signatures between the simulated mixtures and the complex sample responses. As an example, this methodology was applied to screen interfering species relevant to the application of schizophrenia management. Specifically, blood serum measurement of antipsychotic clozapine and antioxidant species can provide useful information regarding therapeutic efficacy and psychiatric symptoms. This work proposes an investigational tool that can guide multi-analyte sensor design, chemometric modeling and biomarker discovery.     

Factors Affecting Gender Differences in the Association between Health-Related Quality of Life and Metabolic Syndrome Components: Tehran Lipid and Glucose Study

Objective

Using structural equation modeling, this study is one of the first efforts aimed at assessing influential factors causing gender differences in the association between health-related quality of life (HRQoL) and metabolic syndrome.

Methods

A sample of 950 adults, from Tehran Lipid and Glucose Study were recruited for this cross sectional study in 2005–2007. Health-related quality of life was assessed using the Iranian version of SF-36. Metabolic syndrome components (MetSCs) and physical and mental HRQoL were considered as continuous latent constructs explaining the variances of their observed components. Structural equation modeling was performed to examine the association between the constructs of MetSCs and the physical and mental HRQoL within the two gender groups.

Results

Based on the primary hypothesis, MetSCs and HRQoL were fitted in a model. The negative effect of MetSCs on HRQoL was found to be significant only in the physical domain and only in women. The proportion of all the cardio-metabolic risk factors as well as subscales of physical HRQoL that have been explained via the two constructs of MetSCs and HRQoL, respectively, were significantly higher in women. Physical activity in both men (β = 3.19, p<0.05) and women (β = 3.94, p<0.05), age (β = -3.28, p<0.05), education (β = 2.63, p<0.05) only in women and smoking (β = 2.28, p<0.05) just in men, directly affected physical HRQoL. Regarding the mental domain, physical activity (β = 3.37, p<0.05) and marital status (β = 3.44, p<0.05) in women and age (β = 2.01, p<0.05) in men were direct effective factors. Age and education in women as well as smoking in men indirectly affected physical HRQoL via MetSCs.

Conclusion

Gender differences in the association between MetSCs and physical HRQoL could mostly be attributed to the different structures of both MetSCs and physical HRQoL constructs in men and women. Age and smoking are the most important socio-behavioral factors which could affect this gender-specific association in the mental domain.     

Dielectrical Properties of CeO2 Nanoparticles at Different Temperatures

A template-free precipitation method was used as a simple and low cost method for preparation of CeO₂ nanoparticles. The structure and morphology of the prepared nanoparticle samples were studied in detail using X-ray diffraction, Raman spectroscopy and Scanning Electron Microscopy (SEM) measurements. The whole powder pattern modelling (WPPM) method was applied on XRD data to accurately measure the crystalline domain size and their size distribution. The average crystalline domain diameter was found to be 5.2 nm, with a very narrow size distribution. UV-visible absorbance spectrum was used to calculate the optical energy band gap of the prepared CeO₂ nanoparticles. The FT-IR spectrum of prepared CeO₂ nanoparticles showed absorption bands at 400 cm^-1 to 450 cm^-1 regime, which correspond to CeO₂ stretching vibration. The dielectric constant (ε_r) and dielectric loss (tan δ) values of sintered CeO₂ compact consolidated from prepared nanoparticles were measured at different temperatures in the range from 298 K (room temperature) to 623 K, and at different frequencies from 1 kHz to 1 MHz.     

Evaluation of Serum & Salivary IgA in Patients with Type 1 Diabetes

Background

Diabetes mellitus is a common immune mediated disorder. The aim of the present study is to evaluate the level of serum and salivary IgA levels in patients with Type 1 diabetes.

Material and Method

In this case control study, serum and salivary IgA levels of patients with diabetes type 1 and similar non diabetes subjects were measured. Age, gender, duration of diabetes and the last HbA1c level of diabetic patients were also studied. Data was analyzed by SPSS software.

Results

Two hundred and fifty subjects (126 diabetics and 124 non diabetics) were enrolled in the study. The mean value of serum IgA in patients with Type 1 Diabetes and controls was 1.77± 1.55 g/lit and 2.39± 1.52 g/lit, respectively. The mean salivary IgA level in diabetics and controls was 276 ± 162.5 40 μg/ml and 129 ± 112.2 40 μg/ml, respectively. Selective IgA deficiency was detected in two (1.6%) and three(2.4%)cases of diabetic and control group; respectively (p=0.68). We found low salivary IgA level in 44.4% diabetic and 33.9% control (p=0.08). There was no significant correlation between serum and salivary IgA level. There was also significant association between serum IgA levels with age. Salivary IgA was significantly correlated with HbA1c level. But considering gender, duration of diabetes we didn’t find any association.

Conclusion

We didn''t find any significant difference in serum and salivary IgA level among diabetic and non diabetics and also, no association between serum and salivary IgA levels.     

In Planta Variation of Volatile Biosynthesis: An Alternative Biosynthetic Route to the Formation of the Pathogen-Induced Volatile Homoterpene DMNT via Triterpene Degradation in Arabidopsis Roots

Plant-derived volatile compounds such as terpenes exhibit substantial structural variation and serve multiple ecological functions. Despite their structural diversity, volatile terpenes are generally produced from a small number of core 5- to 20-carbon intermediates. Here, we present unexpected plasticity in volatile terpene biosynthesis by showing that irregular homo/norterpenes can arise from different biosynthetic routes in a tissue specific manner. While Arabidopsis thaliana and other angiosperms are known to produce the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) or its C₁₆-analog (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene by the breakdown of sesquiterpene and diterpene tertiary alcohols in aboveground tissues, we demonstrate that Arabidopsis roots biosynthesize DMNT by the degradation of the C₃₀ triterpene diol, arabidiol. The reaction is catalyzed by the Brassicaceae-specific cytochrome P450 monooxygenase CYP705A1 and is transiently induced in a jasmonate-dependent manner by infection with the root-rot pathogen Pythium irregulare. CYP705A1 clusters with the arabidiol synthase gene ABDS, and both genes are coexpressed constitutively in the root stele and meristematic tissue. We further provide in vitro and in vivo evidence for the role of the DMNT biosynthetic pathway in resistance against P. irregulare. Our results show biosynthetic plasticity in DMNT biosynthesis in land plants via the assembly of triterpene gene clusters and present biochemical and genetic evidence for volatile compound formation via triterpene degradation in plants.     

The effect of radiotherapy and chemotherapy on osmotic fragility of red blood cells and plasma levels of malondialdehyde in patients with breast cancer

BackgroundGamma radiation effects on the erythrocyte membrane from three different functional parts, lipid bilayer, cytoskeleton and protein components. When the red cell membrane is exposed to radiation, it loses its integrity and hemoglobin leaks out. In addition, irradiation leads to lipid peroxidation and the products of this process, leading to hemolysis. The aim of the present study was to measure osmotic fragility (OF) of red blood cells and malondialdehyde (MDA) levels as a marker of oxidative injury in breast cancer patients treated with radiation and chemotherapy.Materials and MethodsThe OF test was performed using different concentrations of a salt solution. The measurement of MDA was done with chemical methods.¹¹ The sampling was taken during three stages of treatment: first sample was taken before starting chemotherapy, the second sample was taken before radiation therapy and the third sample was taken after radiotherapy.ResultsNo statistically significant differences between levels of MDA in these three stages of treatment were observed. However, the comparison of mean levels of MDA showed an increase after radiotherapy. The OF rate did not show significant difference (P > 0.05) during the stages of treatment.ConclusionIn a standard treatment program of radiotherapy and chemotherapy lipid peroxidation level and OF do not significantly increase.     

Efficacy of two entomopathogenic nematodes Heterorhabditis bacteriophora and Steinernema carpocapsae for control of the leopard moth borer Zeuzera pyrina (Lepidoptera: Cossidae) larvae under laboratory conditions

The biological traits of the entomopathogenic nematodes (EPNs), Steinernema carpocapsae and Heterorhabditis bacteriophora, against the larvae of the leopard moth, Zeuzera pyrina were evaluated in the laboratory. The traits included pathogenicity, penetration potential as well as foraging behaviour. Plate assays were performed using a range of EPN concentrations (5, 10, 20, 50 and 100 infective juveniles (IJs) per larva). The LC₅₀ values for S. carpocapsae and H. bacteriophora were 6.4 and 8.4 IJs larva^?1 after 72 h. Both EPN species caused high mortality in branch experiments. Significantly higher mortality rates occurred in the larger larvae after exposure to S. carpocapsae. Both EPN species successfully penetrated the Z. pyrina larvae as well as larvae of Galleria mellonella L. (Lepidoptera: Galleridae).The proportional response of H. bacteriophora to host-associated cues was strongly higher than S. carpocapsae in Petri dishes containing agar 1, 12 and 24 h after EPN application. These results highlight the efficiency of EPNs for the control of Z. pyrina larvae. However, due to the cryptic habitat of Z. pyrina larvae in their galleries in the trees, field trails need to be conducted to further evaluate this potential.