Promotion of self-nucleic acid fragments on the assembly of foot-and-mouth disease virus-like particles / 生物工程学报

The special nucleic acid fragments, 5' untranslated region (5' UTR) and internal ribosome entry site (IRES) of foot-and-mouth disease virus (FMDV), which interact with the capsid proteins, were selected as scaffolds to investigate the assembly efficiency of foot-and-mouth disease (FMD) virus-like particles (VLPs). The assembled product was characterized by evaluation of particle size, surface potential, gel retardation assay, nuclease digestion experiments, size-exclusion chromatography, transmission electron microscopy and circular dichroism analysis. The results confirmed that the 5' UTR and IRES of FMDV co-assembled with the FMD VLPs and facilitated the assembly efficiency of FMD-VLPs. It demonstrates that the assembly efficiency of 75S particles of VLPs-5'UTR was significantly higher than those of the VLPs (P<0.001) and VLPs-IRES group (P<0.01). Comparatively the assembly efficiency of 12S particles of VLPs-IRES was significantly higher than those of the VLPs (P<0.000 1) and VLPs-5'UTR (P<0.000 1). It showed that the 5' UTR represented more effective in facilitating the assembly of VLPs. This study proposes an optimized strategy for improving the assembly efficiency of VLPs for the development of VLPs vaccine.

Latest progress in postmortem interval estimation / 法医学杂志

Accurate estimation of the postmortem interval (PMI) has been one of the most important and complicated issues in the forensic practice. In order to provide novel perspectives for the future research concerning PMI, the advantages and disadvantages of related traditional methods, postmortem degradation of nucleic acid and tissue, the componential change of vitreous humor and histological biochemistry since 2002 have been introduced and compared in this review.

Application of nucleic acids and proteins in estimation of postmortem interval / 法医学杂志

Accurate estimation of postmortem interval (PMI) is one of the most important and difficult issues in forensic medicine. After death, the tissues autolyze and biomacromolecules degrade. DNA concentration decreases gradually with linear relationship with PMI. The housekeeping gene mRNA, for example beta-actin, GAPDH, has certain stability and can be used to PMI estimation as internal standard. This paper reviews the research progress and problems about DNA, RNA and proteins in the estimation of PMI in order to provide guidance for forensic pathology.

Review on estimation of postmortem interval using FTIR spectroscopy / 法医学杂志

Estimation of the postmortem interval (PMI) is a practical task in daily forensic casework. Researches on PMI is an important practical project in forensic field. Estimation of the time since death is influenced by internal and external, antemortem and postmortem factors, thus the old methods have limitations. Fourier transform infrared (FTIR) spectroscopy has been applied to study the pure protein, nucleic acid and carbohydrate and to detect the changes in complex cells and tissues. At present because the powerful software has could be used to achieve the spectrum transformation, smoothing, baseline correction and normalization, it is possible to analyze the samples quantitatively with the FTIR which has been applied in the biology and clinical medicine. This paper has reviewed the mechanism of FTIR and its application in biomedicine. The postmortem FTIR spectral changes were also discussed, which showed its potential for estimating PMI.

Estimation of postmortem interval using FTIR spectroscopy in rats' cardiac muscle / 法医学杂志

OBJECTIVE@#FTIR (Fourier transform infrared) spectroscopy was applied to observe the process of postmortem degradation in rats' cardiac muscle and provided a new method for the estimation of post-mortem interval (PMI).@*METHODS@#The rats were sacrificed by cervical dislocation and the bodies were kept in a controlled environmental chamber set at (20 +/- 2) degrees C. The FTIR spectra was applied to measure the changes of different chemical group from rats' left ventricle muscle at the different time point postmortem.@*RESULTS@#There were not obvious changes for the main FTIR absorbance peaks. But the different FTIR absorbance at the wave-number (cm(-1)) indicated the three types: increase, decrease, stable. The various absorbance ratios also demonstrated the similar changes.@*CONCLUSION@#FTIR spectroscopy may be potentially used as an effective method for estimating PMI in forensic practice using cardiac muscle tissue.

Short nucleotide sequences signal spliceosomal binding in nucleic acids.

We have explored the region around the splice sites of the human intron and exons from the exon-intron database (EID) and located a number of short 6-nucleotide and 7-nucleotide sequences that are relatively common in the regions. These short sequences, we expect play an important role in the selection of the appropriate splicing process. We propose that the external signals via short recognition sequences play the deterministic role in the actual splicing process. We have obtained 50 such sequences each from the exon and intron from the beginning and from the ending and noted a number of common features.

Biochemical changes induced by chlorpyrifos, an organophosphate compound in sublethal concentrations to the freshwater fish Catla catla, Labeo rohita and Cirrhinus mrigala.

Freshwater fishes, Catla catla, Labeo rohita and Cirrhinus mrigala were exposed to sublethal concentration of the pesticide chlorpyrifos an organophosphate pesticide. Biochemical changes in total glycogen, total proteins, lactate dehydrogenase (LDH), alanine amino transferase (ALAT) and aspartate amino transferase (AAT) and nucleic acids, Deoxy and ribose, were estimated in the tissues of fishes exposed to the toxicant chlorpyrifos technical grade. The decrease in total glycogen and proteins over control and increase in selected enzymes, LDH, AAT, ALAT, DNA and RNA values were observed in the three fishes exposed to the toxicant.

Effect of paper mill effluent on germination of green gram (Phaseolus aureus Roxb.) and growth behaviour of it's seedlings.

Effect of paper mill effluents on Phaseolus aureus Roxb was studied. The effluent significantly inhibited germination of root and shoot length. The bio-chemical injury does not appear spontaneously but with the increase in effluent treatment there is reduction in observed biochemical parameters (chlorophyll, protein, amino acid, nuclic acids and carbohydrate) which are negatively correlated. The shoots of the seedlings were found to be resistant; whereas roots of the seedlings were susceptible to paper mill effluent treatment.

Vitamin C and onion juice versus aflatoxin B1 effect on liver nucliec acids of rats: a quantitative histochemical study

In this study four groups of adult female albino rats were used [each 12 rats] first was used as control the second was given aflatoxin B1 intraperitoneal [i.p.] at a dose of 1 mg/kg/day for 5 consecutive days the third was treated as the second, in addition to administration of Vit. C i.p. at a dose of 10 mg/kg/day for 5 consecutive days, while the fourth one was treated also as the second and given onion juice at a dose of 20 ml/kg/day for 5 consecutive days. The quantitative histochemical analysis of liver DNA and RNA was done by measuring their optical density by Licca quantimat 500 + Image Analyzer Equipment. England [easy, rapid technique and supplied by a personal computer]. There was a significant decrease in DNA [65.89%] and RNA [71.19%] levels in the aflatoxin group when compared with control and decreased significantly when compared with the other two treated groups. These changes were related to the effect of aflatoxin and its epoxides on nucleic acids metabolism and formation of nucleic acid adducts.The aflatoxin-Vit. C and aflatoxin-onion juice groups showed non significant change when compared with the control i.e. improved and reached nearly to the control levels. This improvement was explained mainly by the anti-oxidant effect of Vit-C and onion juice constituents as S. methyl methane thiosulfonate and S. methyl-L.cysteine sulfoxide, in addition to some aromatic isothiocyanates, as well as some organosulphur compounds that proved to have an antimutagenic and/or anticarcinogenic effects

Effect of exercise on transplanted extensor digitorum longus muscle in Sprague Dawley rats.

Effect of exercise has been studied on intact and transplanted extensor digitorum longus (EDL) muscle in rats. Majority of muscle fibres hypertrophied and a few showed hyperplasia in intact and transplanted EDL muscle after exercise. The weight, dimensions and diameter of muscle fibres increased, while total muscle area, number of muscle fibres and the number and diameter of nuclei decreased after exercise in all the experimental groups. The DNA, RNA and protein contents were however increased after exercise.

Regeneration following orthotopic transplantation of entire plantaris muscle in Sprague Dawley rats.

Regeneration of rat plantaris muscle has been studied without predeneration. The original muscle fibres were completely degenerated within one week, but were completely regenerated at the end of experiment. The weight of regenerate showed 51% recovery. The breadth, length and total area of muscle and number of muscle fibres was less by 42, 37, 26 and 29% respectively, compared to control muscle at the end of experiment. The diameter of regenerated fibres was almost normalized at the end of experiment. The number and diameter of nuclei in the regenerate was more than that of control which coincides with the increase in DNA and RNA contents. The protein contents after an initial loss started increasing and continued to do so till the end of the experiment. The better regeneration of the plantaris muscle seems to be due to the presence of supporting gastrocnemius muscle.

Modificaciones de los ácidos nucleicos en ratones inyectados con endotoxina de Escherichia coli: ventajas de la corticoterapia / Modifications of nucleic acids in mice infected with endotoxin of Escherichia coli: advantages of corticotherapy

Recibieron inyecciones intraperitoneales de endotoxina de Escherichia coli 100 ratones MNRI. Algunos se trataron con corticosteroides. A 20 animales testigos se inyectó suero apirógeno. Los animales se sacrificaron 1,6 y 24 horas después de la inyección. Se estudiaron los higados al microscopio óptico (por la técnica de verde metilo y pironina) y al microscopio eletrónico. En el grupo experimental se observaron una reducción escasa del DNA nuclear, especialmente a las 24 horas y una disminución del RNA citoplasmático desde la sexta hora acompañada de redución en el número de los riosomas y en el tamaño del retículo endoplásmico. Los cambios del ADN y el ARN observados en el hígado fueron tardíos; por lo tanto, los trastornos metabólicos son secundarios a las alteraciones vasculares del choque endotóxico. Los resultados sugieren lo adecuado de la corticoterapia para el tratamiento del choque por microorganismo gramnegativos