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Biomedical subjects

X Q Chen

Publications and source records attributed to X Q Chen.

72 records · Page 4Linked to original sources
PubMed1992

[Effect on anti-aging and treating yang deficiency of kidney with huanshao dan capsules. A clinical report of 309 cases].

In this study, with various dosages of huanshao dan capsules, an old Chinese medicine formula, the authors treated the patients with Yang-deficiency of kidney for 1.5-3 months and compared the effects of huanshao dan with those of watered pills and placebo. The analyses of Ridit's showed not only the scores of symptoms of the great-dose huanshao dan group (group 2), the great-dose watered pill group (group 3), the small-dose watered pill group (group 4) and but even the short-treating course group (group 5) were remarkably improved after treatment (P less than 0.001, P less than 0.01); but the group 6 have not any difference after treatment. However, the functions of liver and kidney, the level of cholesterol, the concentration of blood sugar, blood pressure and heart rate remained the same after treatment. The scores of the ability of prompt memory as well as serum lipid peroxide, serum adrenocortical hormone, cellular immunological function, index of glycoprotein and T3, T4 had similar changes. Our data suggested that both huanshao dan and watered pills were beneficial for anti-aging process and there was no noticeable difference between the two drugs.

Aged↗
PubMed1991

Transformation of human breast epithelial cells by c-Ha-ras oncogene.

To determine whether the c-Ha-ras oncogene plays a role in the initiation of mammary carcinogenesis, an immortalized human breast epithelial cell line, MCF-10A, was transfected with the plasmid vector pHo6T1 containing the T24 Ha-ras oncogene and the aminoglycoside phosphotransferase gene, which confers resistance to geneticin. Transfected cells exhibited an altered pattern of growth and tridimensional morphology in collagen gel. They also exhibited anchorage-independent growth and loss of requirement for hormones and epidermal growth factor; in addition, they expressed invasiveness and increased collagenolytic activity in an in vitro system and became tumorigenic in irradiated nude mice, all properties indicative of malignant transformation. Transformed cells contained the mutated c-Ha-ras oncogene and expressed the p21 mutated protein. These data indicate that the c-Ha-ras oncogene is capable of inducing malignant phenotypes in immortalized human breast epithelial cells.

Breast↗
PubMed1991

Linker mutation scanning of the genes encoding the adenovirus type 5 terminal protein precursor and DNA polymerase.

The replication of adenovirus DNA requires, in addition to several host factors, three virus-encoded proteins: a DNA binding protein, the precursor of the terminal protein (pTP), and a DNA polymerase (Ad pol). Ad pol and pTP form a tight complex that is necessary for the initiation step in DNA replication. To perform mutation scanning of the adenovirus type 5 pTP and Ad pol a series of in-frame linker insertions of a 12-mer oligonucleotide d(CCCATCGATGGG) were introduced into cloned viral DNA fragments containing coding sequences of these proteins. The insertions are located at recognition sites for several blunt end-cutting restriction endonucleases. Forty different sites were mutagenized and the mutated genes were transferred to a plasmid that contains the left 42% of the adenovirus genome. They were rebuilt into the viral genome by means of in vivo recombination between plasmid DNA and digested adenovirus DNA-TP complex. The resulting viral genomes were tested for viability and rescued virus was analyzed for the presence of the inserted linker oligonucleotide. This procedure resulted in recovery of a number of viable virus mutants with insertions in the pTP or Ad pol genes, all of which are phenotypically silent. The other mutations did not allow virus production. The positions of these apparent lethal codon insertion mutations were useful to identify regions of functional importance in both proteins. It can be concluded that the precursor-specific region of pTP plays an important role in virus multiplication.

Adenoviruses, Simian↗
PubMed1991

[Analysis of sister-chromatid exchange rate from peripheral lymphocyte of people exposed to environmental cadmium].

Sister-chromatid exchanges (SCEs) were analyzed using peripheral lymphocyte from 38 persons (20 men and 18 women) who had been exposed to environmental cadmium (Cd), and 9 controls (7 men and 2 women). Correlations between SCE rates and urinary Cd-concentrations were done. There were no significant differences in SCE rates between the Cd-polluted and nonpolluted groups. There were no significant correlations between SCE rates and urinary Cd concentrations.

Adolescent↗
PubMed1990

Cytogenetic investigation in lymphocytes of people living in cadmium-polluted areas.

Chromosome aberrations were analyzed from peripheral lymphocyte cultures of 21 men and 19 women who had been exposed to environmental cadmium, and 11 controls (9 men and 2 women). The average cadmium level in the urine of the Cd-polluted group was 3.32 micrograms/l for men and 3.83 micrograms/l for women. There were significant differences in chromosome aberration frequencies between the Cd-polluted and non-polluted groups. The number of individuals with relatively high aberration frequencies (greater than or equal to 5%) in the Cd-polluted group was greater than in the controls. Individuals with a high cadmium content in urine (greater than or equal to 3 micrograms/l) had higher aberration frequencies and more severe aberration types in comparison with the low-cadmium group (less than 3 micrograms/l). There were significant correlations between chromosome aberration frequencies and urinary cadmium content (r = 0.463). The linear regression equation was determined. Considering the conflicting results in other published reports, it is hard to say that the conclusion that cadmium only acts synergistically to enhance the mutagenicity of other compounds present in the environment is correct. According to our study, environmental cadmium cannot only induce chromosome aberrations but also increases the chromosomal aberration frequencies and the frequency of severe aberration types.

Adult↗
PubMed1989

[Anatomic study of the arteries and nervous plexus of the prostate and their clinical significance].

The arteries and nervous plexus of prostates were observed on 32 sides of male adult cadavers. 74.3% of prostatic arteries were derived from the inferior vesical arteries. The latters divided into branches at a site of 24 +/- 10 mm above 4(8) o'clock point of intervesico-prostatic sulcus. According to the anatomical results, the authors have put and used a new hemostatic method ligating the inferior vesical arteries prior to the section of the hyperplastic gland tissue in 18 cases. Bleeding volume in the operations was 80 ml average. The various color varied from red to clean was 90 minutes average after the operations.

Arteries↗
PubMed1988

Nerves accompanying the vertebral artery and their clinical relevance.

In elucidating the morphologic basis of cervical spondylosis, the nerves accompanying the vertebral artery were studied under an operative microscope and by means of Karnovsky's histochemical method for acetylcholinesterase (AChE). The results show that the nerves arising from the cervical part of the sympathetic trunk and the cervical nerves anastomose with each other around the artery, and are distributed to the vertebral artery and the cervical spine. The nerves accompanying the vertebral artery show different degrees of AChE activity, and may be compressed or stimulated as a result of disease of Luschka's joint and the other degenerated structures, based on their anatomic relationship.

Acetylcholinesterase↗
PubMedDate not supplied

Effects of inner water volume on the peculiar surface morphology of microspheres fabricated by double emulsion technique.

Poly(D,L-lactide-co-glycolide) (PLG, 65:35) was used to encapsulate bovine serum albumin (BSA) using a water-in-oil-in-water (W/O/W) double emulsion solvent extraction technique. To investigate the effects of an inner water/oil ratio on microsphere characteristics, microspheres were fabricated using four different formulations with a fixed oil volume of 12ml and the inner aqueous phase volume of 0.2ml, 0.3 ml, 0.4ml or 0.5 ml, respectively. Spherical microspheres were obtained after collection by filtration for formulations employing any of the four different inner water/oil ratios. However, microspheres with smaller inner water volumes tend to collapse after vacuum drying. The surface of the formulation with a higher inner water/oil ratio was shown to possess many more pores than that of the formulations with lower inner water/oil ratios. These pores may facilitate the water withdrawal during vacuum drying. Furthermore, microspheres with the lowest inner water/oil ratio (1/60) had higher initial burst release due to its larger surface area. However, microspheres with the highest inner water volume yield a faster release profile of BSA due to interconnected voids within microspheres and more pores on the surface. Therefore, the inner water/oil ratio is a crucial factor in the W/O/W double emulsion technique affecting the morphology and release kinetics of the resulting microspheres.

Drug Delivery Systems↗