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Abstract  

The important existing quantitative PCR techniques, including the classification, description, evaluation and effect factors have been reviewed. Emphases are put on the types and evaluation of quantitative internal standard substances as well as the theoretical consideration of PCR quantitative process. The purpose is reasonably to establish our own detection protocol for quantification of HCMV in clinical samples.

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Abstract  

An external standard method for PCR quantification of HCMV was reported. [-32P]dATP was used as a tracer.32P-labelled specific amplification product was separated by agarose gel electrophoresis. A gel piece containing the specific product band was excised and counted in a plastic scintillation counter. Distribution of [-32P]dATP in the electrophoretic gel plate and effect of separation between the32P-labelled specific product and free [-32P]dATP were observed. A standard curve for quantification of HCMV by PCR was established and detective results of quality control templets were presented. The external standard method and the electrophoresis separation effect were appraised. The results showed that the method could be used for relative quantification of HCMV.

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A comparative QSAR and QSRR study has been conducted by multiple linear regression (MLR), principal-component regression (PCR), and partial least-squares (PLS) analysis. Comparisons based on these regression methods have been used to model the chromatographic retention (lipophilicity) of thirteen new oxadiazoline derivatives by means of descriptors obtained by use of the Alchemy software package. Retention indices were determined by reversed-phased high-performance thin-layer chromatography on C 18 plates. The retention indices predicted were quite satisfactory and in very good agreement with the molecular structure of the compounds investigated.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Baptista
,
D. Vieira
,
A. Galisteo-Júnior
,
P. Caproni
,
M. Casare
,
H. de Andrade-Júnior
,
P. Spencer
, and
N. Nascimento

Abstract  

We investigated the immunological behavior of BTHX-1, before and after irradiation. SDS-PAGE showed that BTHX-1 irradiated in the presence of NaNO3, had its structure preserved. Animals’ plasma immunized with native BTHX-1 had high IgG1 titers. The irradiated protein induced high titers of IgG2b. When the toxin was irradiated with t-butanol, there was a slight decrease in the production of IgG2b. Real-time PCR showed that both the IL-2 as for IL4 was more expression from the cells of the animals immunized with BTHX-1 irradiated. These results indicate that irradiation of proteins leads to significant structural modifications.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Mitja Križman
,
Jernej Jakše
,
Mirko Prošek
,
Dea Baričevič
, and
Branka Javornik

Agarose gel electrophoresis is a basic separation tool used in molecular biology, mostly for qualitative DNA analysis. There are constraints limiting its use in quantitative analysis, namely low repeatability and a narrow linear range. However, by using an internal standard or internal normalization, repeatability and linear range could be significantly improved. In the work discussed in this paper it was shown that an approximately fivefold improvement in repeatability and an over threefold wider linear range could be achieved by applying internal normalization. Using the proposed approach, genetic markers, for example RAPD and PCR-RFLP, or even microsatellite markers, could be conveniently quantitatively assessed using agarose gel electrophoresis.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Baptista
,
D. Vieira
,
A. Galisteo Júnior
,
O. Higa
,
M. Casare
,
C. Yonamine
,
P. Caproni
,
L. Campos
,
H. de Andrade Júnior
,
P. Spencer
, and
N. Nascimento

Abstract  

In this work, the authors investigated the immunological behavior of bothropstoxin-I (BTHX-1), before and after irradiation process, and also the influence of scavengers substances on protein alterations induced by free radical production. Structural modifications were investigated by SDS-PAGE in reducing or non-reducing conditions. In vitro cytotoxicity assay was performed to test average toxic activities of BTHX-I. BALB/c Isogenic mice were immunized with irradiated or non-irradiated (native) forms of BTHX-I and antibody titers and isotypes were determined by ELISA method. Expression of murine cytokines was analyzed by using expression data obtained by quantitative real-time PCR (qPCR) assays. The results indicate that irradiation of proteins leads to significant structural modifications, and also changes the cytokines profile during immunization process, regarding a suitable approach to new immunogenic production.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Zhang Yuanxun
,
Zhang Yongping
,
Li Delu
,
Zhang Guilin
,
Long Jiangang
,
Shen Hui
,
Huang Yuying
, and
He Wei

Summary  

In order to explore the interaction between the expression of ZnT3 (Zinc Transporter 3) mRNA (Messenger Ribonucleic Acid) and the concentration of elemental zinc in mouse brain, zinc distribution in brain was determined by synchrotron radiation X-ray fluorescence (SRXRF) technique and a ZnT3 mRNA expression in tissue was examined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method.The results show that the zinc concentration is not evenly distributed in brain slices. Its concentrations in cerebral cortex and hippocampus are nearly 5-10 times higher than those in other positions. A corresponding relation is that ZnT3 mRNA in cerebral cortex, hippocampus and testis has higher abundant degree, but it is not examined out in other tissues. Furthermore, the results promote that ZnT3 facilitates the accumulation of zinc in synaptic vesicles and may play an important role in structuring of vesicular zinc pool.

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This work presents a comparative study on the development and validation of two analytical techniques applied for the simultaneous determination of hydrocortisone acetate (HCA), fusidic acid (FSA), methyl paraben (MPB), and propyl paraben (PPB) formulated as a topical cream. The first technique was thin-layer chromatography (TLC)–densitometric method, which was developed by separating the four components on silica gel 60 F254 using methylene chloride–methanol–benzene in the ratio of 10:2:5, v/v, as the developing system, followed by densitometric measurement of the bands at 240 nm. The second technique was the chemometric method using two models: principle component regression model (PCR) and partial least squares (PLS). The suggested techniques were validated in compliance with the International Conference on Harmonization (ICH) guidelines and were successfully applied for the determination of the quaternary mixtures as prepared synthetically in laboratory and in the commercial topical pharmaceutical formulation.

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Ethyl-levulinate Aldrich >99 d, e c -C 4 F 8 PCR Inc

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response time (delay between sampling and signal provision) is only depending on the thermal time constants of the calorimeter. Furthermore, amplification processes such as PCR or enzyme catalysed reactions are not necessary. This essentially simplifies the

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