[Study on radiation dose in different field of views of oral and maxillofacial cone-beam CT]

Objective: To analyze the absorptive radiation dose of non-target sensitive organs under the NewTomVGi oral and maxillofacial cone-beam CT scanning in different view fields. Methods: The thermoluminescence dosimeter chip was placed in the non-target sensitive organ of the simulated radiology head model, and 6 scanning fields were measured and analyzed (standard resolution: scanning range was 15 cm×15 cm, 15 cm×12 cm, 12 cm×8 cm, 8 cm×8 cm respectively). High definition resolution: the radiation absorption dose of thermoluminescence with the scanning range of 12 cm×8 cm, 8 cm×8 cm, respectively. Results: Under the same resolution, the absorptive dose increased with the expansion of scanning field, and the amount of absorbent during high resolution scanning was higher than that during the standard resolution with the same scanning field. Conclusions: New TomVGi oral and maxillofacial cone-beam CT has sighificant difference in radiation dose in different view fields. The appropriate view field should be selected according to the patient's clinical needs, so as to reduce unnecessary radiation dose during medical imaging examination.

Inhibition of diacylglycerol acyltransferase by prenylated flavonoids isolated from the stem bark of Maackia amurensis

A new prenylated flavanone, erythraddison Z (1), together with eight known flavonoids (2-9), was isolated from the stem bark of Maackia amurensis. Their structures were elucidated on the basis of spectroscopic methods, including 1D and 2D NMR (COSY, HMQC, and HMBC) techniques. All the isolates, with the exception of 3, 6 and 7, strongly inhibited diacylglycerol acyltransferase activity in an in vitro assay with IC50 values ranging from 96.5 ± 0.6 to 135.1 ± 1.4 μM.

[Investigation of a compound, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum on metabolic syndrome treatment III--controlling blood glucose]

Base on the improvement of compound FF16, compatibility of Rhodiola crenulata, Cordyceps militaris, and Rheum palmatum, on both insulin resistance and obesity, its effects on type 2 diabetes (T2DM ) was investigated here. The results showed that the levels of fasting and no-fasting blood glucose were controlled in the spontaneous type 2 diabetes KKAy mice; the impaired glucose tolerance (IGT)was improved by decreasing significantly the values of the glucose peaks and the area under the blood glucose-time curve (AUC ) after glucose-loading in glucose tolerance test (OGTT) in both high-fat-diet-induced pre-diabetes IRF mice and KKAy mice, respectively. The pancreatic histopathological analysis showed that the increased islet amount, the enlarged islet area, and the lipid accumulation in the pancreas were reversed by FF16 treatment in both IRF mice and KKAy mice. In the palmitate-induced RINm5f cell model, FF16 could effectively reduce the apoptosis and enhance the glucose-stimulated insulin secretion, respectively. In conclusion, FF16 could improve the T2DM by protecting the pancreatic beta-cells.

Xiao Han, et al., GHGKHKNK Octapeptide (P-5m) Inhibits Metastasis of HCCLM3 Cell Lines via Regulation of MMP-2 Expression in in Vitro and in Vivo Studies. Molecules, 2012, 17, 1357-1372

The authors wish to make the following correction to this paper [1]: the correct name of the fourth author is Hiroshi Matsuura. [...]

GHGKHKNK octapeptide (P-5m) inhibits metastasis of HCCLM3 cell lines via regulation of MMP-2 expression in in vitro and in vivo studies

P-5m, an octapeptide derived from domain 5 of HKa, was initially found to inhibit the invasion and migration of melanoma cells. The high metastatic potential of melanoma cells was prevented by the HGK motif in the P-5m peptide in vitro and in an experimental lung metastasis model, suggesting that P-5m may play an important role in the regulation of tumor metastasis. The aim of this study was to measure the effect of P-5m on tumor metastasis of human hepatocarcinoma cell line (HCCLM3) in vitro and in vivo in a nude mouse model of hepatocellular carcinoma (HCC), and detect the mechanisms involved in P-5m-induced anti-metastasis. By gelatin zymography, matrix metallo-proteinases 2 (MMP-2) activity in HCCLM3 was dramatically diminished by P-5m peptide. In addition, the migration and metastasis of HCCLM3 cells was also inhibited by the peptide in vitro. In an orthotopic model of HCC in nude mice, P-5m treatment effectively reduced the lung metastasis as well as the expression of MMP-2 in the tumor tissues. Overall, these observations indicate an important role for P-5m peptide in HCC invasion and metastasis, at least partially through modulation MMP-2 expression. These data suggests that P-5m may have therapeutic potential in metastatic human hepatocarcinoma.

Anti-lipid peroxidation effect of Rosa davurica Pall. fruit

OBJECTIVE

To study the anti-lipid peroxidation action of Rosa davurica Pall. fruit.

METHODS

The contents of malondialdehyde (MDA) of the tissue homogenate of the liver, heart, kidney, brain and of the red blood cells induced by hydrogen peroxide in mice were measured. The contents of MDA and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of ischemic myocardium of mice were measured.

RESULTS

0.2 g/L Rosa davurica Pall. fruit could decrease significantly the contents of MDA of the all tissue (P < 0.05). Inhibition rate of 6.7 g/L Rosa davurica Pall. fruit on MDA of the red blood cells induced by hydrogen peroxide was 89.2%. Administration of this extraction successively for six days (ig, 2.0 g x kg(-1) x d(-1)) can significantly reduce the content of MDA (P < 0.01) and augment the activities of SOD and GHS-Px (P < 0.05) in the ischemic myocardium of mice.

CONCLUSION

Rosa davurica Pall. fruit can significantly prevent the lipid peroxidation.

Rat tripeptidyl peptidase I: molecular cloning, functional expression, tissue localization and enzymatic characterization

We purified tripeptidyl peptidase I (TPP I) to homogeneity from a rat kidney lysosomal fraction and determined its physicochemical properties, including its molecular weight, substrate specificity and partial amino acid sequence. The molecular weight of the enzyme was calculated to be 280,000 and 290,000 by non-denaturing PAGE and gel filtration, respectively, and to be 43 000 and 46 000 on SDS-PAGE in the absence and presence of beta-ME, respectively. These findings suggest that the enzyme is composed of six identical subunits. The Km, Vmax, kcat and kcat/Km values of TPP I at optimal pH (pH 4.0) were 680 microM, 3.7 micromol x mg(-1) x min(-1), 33.1 s(-1) and 4.87 x 10(4) s(-1) x M(-1) for Ala-Ala-Phe-MCA, respectively. TPP I was significantly inhibited by PCMBS and HgCl2, and moderately by DFP. These findings also suggest that TPP I is an exotype serine peptidase that is regulated by SH reagent. TPP I released the tripeptide Arg-Val-Tyr from angiotensin III more rapidly than from Ala-Ala-Phe-MCA, and also released Gly-Asn-Leu from neuromedin B with the same velocity as from Ala-Ala-Phe-MCA. Angiotensin III and neuromedin B have recently been found to be good natural substrates for lysosomal TPP I. Furthermore, we determined the rat liver cDNA structure and deduced the amino acid sequence. The cDNA, designated as lambdaRTI-1, is composed of 2485 bp and encodes 563 amino acids in the coding region. By Northern blot analysis, the order for TPP I mRNA expression was kidney > or = liver > heart > brain > lung > spleen >> skeletal muscle and testis. In parallel experiments, the TPP I antigen was detected in various rat tissues by immunohistochemical staining.

Molecular cloning and immunohistochemical localization of rat dipeptidyl peptidase III

Dipeptidyl peptidase III (DPP III) was purified to homogeneity from rat liver cytosol. The calculated molecular weight of the purified enzyme was 82845.6 according to TOF-MS, and 82000 on non-denatured PAGE and 82000 on SDS-PAGE in the absence or presence of beta-ME. These findings suggest that the enzyme assumes a monomeric form in rat liver cytosol. The enzyme rapidly hydrolyzed the substrate Arg-Arg-MCA and moderately hydrolyzed Ala-Arg-MCA in a pH range of 7. 5 to 9.5. The K(in), K(cat) and K(cat)/K(m) values of DPP III at optimal pH (pH 8.5) were 290 microM, 18.0 s(-1) and 6.21x10(4) s(-1)M(-1) for Arg-Arg-MCA and 125 microM, 4.53 s(-1) and 3.62x10(4) s(-1)M(-1) for Ala-Arg-MCA, respectively. DPP III was potently inhibited by EDTA, 1,10-phenanthroline, DFP, PCMBS, NEM, beta-ME and iodoacetamide. Furthermore, we screened a rat liver cDNA library using affinity-purified anti-rat DPP III rabbit IgG, and we determined the cDNA structure and deduced the amino acid sequence. The cDNA designated as lambdaRDIII-11 is composed of 2640 bp of nucleotides in length and encodes 738 amino acids in the coding region. Although the enzyme has a novel zinc-binding motif, HEXXXH in structure, DPP III is thought to belong to family 1 in clan MA in the metalloprotease kingdom. These findings suggest that DPP III is a metalloprotease that is probably regulated by SH modification. The DPP III antigen was extensively detected in the cytosol of various rat tissues by the immunohistochemical examination of the protein.

Dipeptidyl peptidase III from rat liver cytosol: purification, molecular cloning and immunohistochemical localization

Dipeptidyl peptidase III (DPP III) was purified to homogeneity from rat liver cytosol. The calculated molecular weight of the purified enzyme was 82845.6 according to TOF-MS and 82000 on non-denaturing PAGE, and 82000 on SDS-PAGE in the absence or presence of beta-mercaptoethanol. These findings suggest that the enzyme exists in a monomeric form in rat liver cytosol. The enzyme rapidly hydrolyzed the substrate Arg-Arg-MCA and moderately hydrolyzed Gly-Arg-MCA in the pH range of 7.5 to 9.5. The Km, k(cat) and k(cat)/Km values of DPP III at optimal pH (pH 8.5) were 290 microM, 18.0 s(-1) and 62.1 s(-1) x nM(-1) for Arg-Arg-MCA and 125 microM, 4.53 s(-1) and 36.2 s(-1) x nM(-1) for Ala-Arg-MCA, respectively. DPP III was potently inhibited by EDTA, 1,10-phenanthroline, DFP, PCMBS and NEM. These findings suggest that DPP III is an exo-type peptidase with characteristics of a metallo- and serine peptidase. For further information on the molecular structure, we screened a rat liver cDNA library using affinity-purified anti-rat DPP III rabbit IgG antibodies, determined the cDNA structure and deduced the amino acid sequence. The cDNA, designated as lambdaRDIII-11, is composed of 2640 bp and encodes 738 amino acids in the coding region. Although the enzyme has a novel zinc-binding motif, HEXXXH, DPP III is thought to belong to family 1 in clan MA in the metalloprotease kingdom. The DPP III antigen was detected in significant amounts in the cytosol of various rat tissues by immunohistochemical examination.