Confocal laser scanning microscopy of nanoparticles applied to immunosorbent assays

The aim of this project was to demonstrate and develop a confocal readout method for fluorescent immunosorbent assays and investigate its potential advantages in comparison to traditional immunoassays. The key point of a confocal immunosorbent assay is the ability to detect the thin layer of immunoassay in the presence of unbound fluorescent reagents without washing the overlayer. Heterogeneous and homogeneous sandwich immunoassays of human IgG model were demonstrated successfully followed by the use of an empirical decomposition method for quantitative separation of the signals of the thin fluorescent assay layer from the overlayer. The detection limits for the homogeneous and heterogeneous formats of the model were 2.2 and 5.5 ng/ml, respectively. The application of confocal microscopy in kinetic analysis of the antigen-antibody reaction of the human IgG model was studied for homogeneous and heterogeneous formats and two fluorescent labels antibodies (FITC and QDs)

Morphometric alterations to the rat spleen following formaldehyde exposure

Formaldehyde is commonly used in the production of various industrial and medical products. At room temperature formaldehyde easily evaporates. Exposure to formaldehyde can be hazardous to human health. Studies show that the vapour can be the cause of clinical symptoms such as throat, eye, skin and nasal irritation. It can also decrease the production of IgM in the spleen cells. This study was designed to determine the morphometric changes to the spleen in rats when samples were exposed to formaldehyde for 18 weeks. A total of 28 albino Wistar rats aged 6-7 postnatal weeks were divided into the following three case groups according to their exposure to formaldehyde: E1 (2 h/day, 2 days/week), E2 (2 h/day, 4 days/week), E3 (4 h/day, 4 days/week) and one control group. When the exposure period had expired the animals were anaesthetised with chloroform. After cervical dislocation, the abdomen was dissected and spleen specimens were taken. These were sectioned and stained with the haematoxylin and eosin technique for morphometric study. Data was obtained from an Olympus light microscope and then analysed with SPSS (version 11.5) and one-way ANOVA test. The white pulp area and diameter and the marginal zone diameter were greater in group E3 than those in the other groups. The germinal centre area and diameter and the diameter of the periarterial lymphoid sheaths (PALS) were greater in group E2 than in other groups, although there was no significant difference between groups in the area of white pulp and the PALS diameter (p < 0.05). This study showed that formaldehyde vapour can cause morphometric changes in the white pulp of the spleen in rats. Copyright © 2008 Via Medica

Age, growth and spawning season of Luciobarbus esocinus Heckel, 1843 in Gamasiab River, Iran

In the current paper reproductive strategy and growth rates of Luciobarbus esocinus were investigated from 2010 to 2012, in Gamasiab River, Kermanshah, Iran. Samples were collected seasonally by gillnet and electro-fisher device. Sex ratio was evaluated from 162 individuals and the percentage of male and female individuals were 54.76% and 45.24% respectively. Age structure was distributed between I and V and most frequency numbers for males and females belonged to II and IV age group, respectively. Length-weight relationship was computed as W=8E-05TL^2.6546 for all individuals. Mean total length and weight was 333.82±13.10 mm and 297.67±4.85 g for males, and 371.5±21.17 mm and 307.85±7.64 g for females. The von-Bertalanffy growth models of L. esocinus were described as Lt =357.14×[1-e^(-0.77×(t-0.090))] for males, Lt =367.02×[1-e^(-0.78×(t–0.094))] for females and Lt =363.57×[1-e^(-0.76×(t –0.087))] for both sexes. Results indicated that growth factors were highly similar in spring, summer and winter. CDA analysis revealed that the total and gonad weight are the main factors in discriminant analysis. The highest GSI values were found in spring for females and winter for males, however, it decreased rapidly after spring in females. Maximum growth rates were observed in early ages (I-II) and depleted with ages. K value and L∞ were determined as 0.77±0.09 Y^-1 and 357.14±10.38 mm for males and 0.78±0.24 Y^-1 and 367.02±24.15 mm for females, respectively. In conclusion this study provided basic information for stock assessment and management of L. esocinus in Gamasiab Reservoir

Exact Shock Profile for the ASEP with Sublattice-Parallel Update

We analytically study the one-dimensional Asymmetric Simple Exclusion Process (ASEP) with open boundaries under sublattice-parallel updating scheme. We investigate the stationary state properties of this model conditioned on finding a given particle number in the system. Recent numerical investigations have shown that the model possesses three different phases in this case. Using a matrix product method we calculate both exact canonical partition function and also density profiles of the particles in each phase. Application of the Yang-Lee theory reveals that the model undergoes two second-order phase transitions at critical points. These results confirm the correctness of our previous numerical studies.Comment: 12 pages, 3 figures, accepted for publication in Journal of Physics

Modifying the transition temperature, 120 K ≤ Tc ≤ 1150 K, of amorphous Fe90−xCoxSc10 with simultaneous alteration of fluctuation of exchange integral up to zero

Amorphous (a-) Fe90−xCoxSc10 alloys have been produced by rapid quenching from the melt. The Curie temperature, TC, was determined using both mean field theory and Landau’s theory of second-order phase transitions in zero and non-zero external fields. The dependence of TC on the atomic spacing can be explained by the empirical Bethe-Slater curve. The value of TC of a- Fe5Co85Sc10, determined by the above theoretical approaches is 1150 K, which is the highest TC ever measured for amorphous alloys. The flattening of the measured normalized magnetization, M(T)/M(0), as a function of the reduced temperature, T/TC, is explained within the framework of the Handrich- Kobe model. According to this model the fluctuation of the exchange integral is the main reason for the flattening of M(T)/M(0). In the case of a-Fe90Sc10 without Co, however, the fluctuation of the exchange integral is dominant only at zero external field, Bex = 0. At Bex = 9 T, however, the fluctuation of the exchange integral has no conspicuous effect on the reduction of the magnetization. It is shown that at Bex = 9 T the frozen magnetic clusters control the behaviour of the reduced magnetization as function of T/TC. In contrast to other ferromagnetic alloys, where the flattening of M(T)/M(0) is characteristic for an amorphous structure, the a- Fe5Co85Sc10 does not exhibit any trace of the fluctuation of the exchange integral

Conclusive experimental demonstration of one-way Einstein-Podolsky-Rosen steering

Einstein-Podolsky-Rosen steering is a quantum phenomenon wherein one party influences, or steers, the state of a distant party's particle beyond what could be achieved with a separable state, by making measurements on one half of an entangled state. This type of quantum nonlocality stands out through its asymmetric setting, and even allows for cases where one party can steer the other, but where the reverse is not true. A series of experiments have demonstrated one-way steering in the past, but all were based on significant limiting assumptions. These consisted either of restrictions on the type of allowed measurements, or of assumptions about the quantum state at hand, by mapping to a specific family of states and analysing the ideal target state rather than the real experimental state. Here, we present the first experimental demonstration of one-way steering free of such assumptions. We achieve this using a new sufficient condition for non-steerability, and, although not required by our analysis, using a novel source of extremely high-quality photonic Werner states.Comment: Supplemental Material included in the documen

ABCB1 variants C3435T and T129C are not associated with colorectal cancer risk

Background: Colorectal cancer (CRC) is one of the most prevalent cancers in Saudi Arabia that is highly characterized with poor survival rate and advanced metastasis. Many studies contribute this poor outcome to the expression of ABC transporters on the surface of cancer cells. Objectives: In this study, two ABCB1 variants, C3435T and T129C, were examined to evaluate their contribution to CRC risk. Methods: 125 subjects (62 CRC patients and 63 healthy controls) were involved. The DNA was isolated and analyzed with PCR-RFLP to determine the different genotypes. The hardy-Weinberg equilibrium was performed to determine genotype distribution and allele frequencies. Fisher\u2019s exact test (two-tailed) was used to compare allele frequencies between patients and control subjects. Results: The study showed that for SNP C3435T, the population of both CRC patients and controls were out of Hardy-Weinberg equilibrium. Genotype distribution for CRC patients was (Goodness of fit \u3c72 = 20, df= 1, P 640.05), whereas, for the controls the genotype distribution was (Goodness of fit \u3c72 = 21, df =1, P 640.05). For SNP T129C, all subjects showed normal (TT) genotype. Conclusion: There was no significant association between ABCB1 3435C&gt;T and 129T&gt;C polymorphisms with CRC risk

Comparative Study of the Antioxidant Activity of Two Popular Green Tea Beverages Available in the Local Market of Saudi Arabia

Abstract Antioxidants have numerous applications due to their multiple roles in diminishing harmful effects of oxidative stress. The objective of this work was to highlight the importance of green tea by evaluating the antioxidant activity of the most popular green tea brands in Saudi Arabia, Lipton and Rabea. To our knowledge, no studies have so far been done to estimate the antioxidant activity of these brands. To determine the antioxidant activities of these two brands, 10 mg/ml of each brand was extracted and their total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, hydrogen peroxide scavenging activity, ferric reducing power and ferrous ion chelating effect were measured. The TPC of Lipton tea was 678.7 µg of gallic acid equivalents (GAE)/10mg, whereas in Rabea tea, the TPC was 647.1 µg GAE/10mg. The presence study indicated that there were no significant differences in total phenolic contents and the percentage inhibition as shown in DPPH and H 2 O 2 assays among Lipton and Rabea green teas. Moreover, it was found that all assays have exhibited high antioxidant activity in both green teas. In conclusion, our study showed evidence for evenness and stability of the antioxidant activity of the two commercial green teas available in the markets of Saudi Arabia. Continued researches are needed to further the current knowledge on the health-promoting effects of this popular beverage using different supplements by different mechanisms