Study to elucidate molecular mechanism behind zinc chemo-preventive role during lung carcinogenesis.

OBJECTIVE: The present planned to elucidate the mechanistic role zinc supplementation in the modulation of p53 post-translational acetylation, the activity of cyclooxygenase-2 (COX-2) along with other biophysical parameters during benzo(a)pyrene (BP) induced lung carcinogenesis in mice. MATERIALS AND METHODS: The mice were segregated into four groups viz., normal control, BP treated, BP + zinc and zinc alone treated. Lung carcinogenesis was induced by a single intra-peritoneal (IP) injection of BP (100 mg/kg body weight). Zinc was supplemented to mice at dose levels of 227 mg/kg body weight in drinking water. All the treatments were continued for 20 weeks. RESULTS: The BP caused a significant rise in the expression of p53. On the other hand, protein expressions of acetylated (lys382)-p53 were significantly decreased, following BP treatment. Also, a significant decrease was observed in the enzyme activities of caspase 3 and caspase 9. Moreover, BP treatment brought about a significant increase in the activity of COX-2. Supplementation of zinc to BP treated mice stimulated acetylation of p53 as observed by an increase in the protein expression of acetylated (lys382)-p53. Also, the enzyme activities of caspase 3 and caspase 9 showed a significant elevation upon zinc supplementation. On the other hand, the zinc supplementation brought about moderation in the expression of enzymatic activity of COX-2 which was restored within the normal limits. Further, BP treatment recorded increased 3H-thymidine uptake as well as enhanced 14C-glucose uptake and its turnover which were reduced significantly following simultaneous treatment with zinc. CONCLUSIONS: The treatment with zinc has the potential to modulate p53 acetylation to stimulate apoptosis against experimentally induced lung carcinogenesis.

Evaluation to the effect of B2O3-La2O3-SrO-Na2O-Al2O3 bonding agent on Ti6Al4V-porcelain bonding.

Low-fusing bonding agents have been widely applied in Ti-ceramics restorations. As an important category, borate bonding agents have great potentials in increasing Ti-porcelain bonding. The purpose of this study is to evaluate the effect of borate bonding agent with addition of Na2O and Al2O3 on Ti6Al4V-porcelain bonding. The thermal properties of borate bonding agent, such as glass transition temperature (Tg) and crystallization peak temperature (Tp), were investigated to establish the sintering process. And the coefficient of thermal expansion (CTE) was to evaluate the matching effect of porcelain to Ti6Al4V. The bond strength was analyzed by the three point bending test. The microscopic morphology of the borate bonding agent surface after sintering, the interface of Ti-borate bonding agent-porcelain, and the fracture mode after porcelains fracture, were studied to assess the influence of borate bonding agent on Ti6Al4V-ceramics. With the addition of Na2O and Al2O3, the porcelain residues were observed increased indication on the Ti6Al4V surface after porcelain fracture and the bond strength was acquired the maximum (49.45MPa) in the bonding agent composition of 75.70B2O3-5.92La2O3-11.84SrO-4.67Na2O-1.87Al2O3. Those results suggest that borate bonding agent is an effective way to improve the Ti6Al4V-ceramics bond strength. And the addition of Na2O and Al2O3 strengthen this effect.

Effects of inulin on performance, egg quality, gut microflora and serum and yolk cholesterol in laying hens.

1. The present study was conducted to investigate the effects of inulin on laying hens. A total of 360 Brown Nick laying hens were divided randomly into 6 groups of 60 with 6 replicates of 10 hens and fed on diets containing 0 (control), 0·1, 0·5, 1·0, 1·5 or 2·0% inulin during the 4-week trial. 2. Dietary supplementation of inulin reduced cholesterol concentration (mg/g yolk) and content (mg/egg) in eggs. Cholesterol content in eggs decreased linearly with increasing levels of dietary inulin level. 3. Supplementation of inulin in diets decreased coliform bacteria counts and pH in the caecum. The lowest coliform bacteria counts (6·30 ± 0·03 log10 cfu/g) and pH (6·47 ± 0·01) were obtained in the 2·0% inulin group, the two indices decreasing by 21·6% and 3·0% respectively, compared with the control group. Coliform bacteria count and pH were changed linearly in accordance with increasing levels of dietary inulin level. Caecal Bifidobacteria counts were increased in the 2·0%-inulin group. 4. Inulin supplementation of layer diets did not appear to have any adverse effects on laying rate, egg weight, feed intake, feed conversion efficiency, cracked-egg rate, eggshell thickness or Haugh unit compared with the control laying hens. 5. Therefore, dietary supplementation with inulin may lead to the development of low-cholesterol chicken eggs as demanded by health-conscious consumers.

ICAAR, a novel member of a new family of transmembrane, tyrosine phosphatase-like proteins.

We have isolated a cDNA from human foetal brain cDNA library which encodes a putative transmembrane protein bearing an intracellular protein tyrosine phosphatase (PTPase) like domain. The PTPase like domain contains an alanine to aspartate amino acid change relative to other PTPases in the catalytic core domain. This amino acid change is found in only three other known proteins, islet cell autoantigens; human, murine and rat IA-2, murine IA-2b and its rat orthologue phogrin, which have a similar overall structure to ICAAR, and the recently identified X-linked myotubular myopathy (MTM1) gene. ICAAR, IA-2 and IA-2b clearly represent a new family of PTP-like proteins for which catalytic activity has yet to be demonstrated. An abundant ICAAR mRNA is detectable in the brain and pancreas but not in the other normal human tissues surveyed. We have localised ICAAR to human chromosome 7q36.

[Isolation and elucidation of a new minor saponin from the leaves of Panax ginseng C.A. Meyer].

The structure of a new minor saponin isolated from the leaves of Panax ginseng C. A. Meyer was elucidated on the basis of chemical evidences and spectral data. The saponin was named as ginsenoside-La.