Biomedical subjects

D Xiang

Publications and source records attributed to D Xiang.

10 recordsLinked to original sources

PubMed2001

[Clinical study on hepatitis D virus-positive patients died from severe hepatitis B].

OBJECTIVE: To investigate the role of hepatitis D virus (HDV) in the development of severe hepatitis B. METHODS: Seventy-six HDV-positive patients died from severe hepatitis B were compared with 244 HDV-negative patients from severe hepatitis B in clinical manifestations, signs, complications and main biochemical indexes at the same period. RESULTS: HDV-positive patients had obvious ascites, abdominal distension, digestive tract hemorrhage as compared with the HDV-negative ones (P<0.05). There were significant differences in hepatorenal syndrome, bacterial infection, manifold complications, the levels of total bilirubin and alanine aminotransferase, and the activity of prothrombin between the patients of the two groups (P<0.01). CONCLUSIONS: HDV can aggravate severe hepatitis B.

Adolescent↗

PubMed2000

[Effect of calcitonin on the proliferation and membrane fluidity of human osteoblast-like cells].

The effects of calcitonin (CT) on the proliferation and membrane fluidity of human osteoblast-like cells line OS-732 were compared with the effect of 1,25(OH)2D3. The rate of DNA synthesis, cell proliferation, cell cycle and membrane fluidity of OS-732 cells were observed. Results showed that 1IU/ml CT stimulated cell proliferation and DNA synthesis. The percentage of cell in the G2 + M phase was increased and the percentage of cell in the synthetic phase was decreased. The membrane fluidity of OS-732 cells was increased after 0.1 mumol/L and 0.01 mumol/L 1,25(OH)2D3 treatment and was decreased after 1IU/ml CT treatment. It is concluded that calcitonin might increase the cell proliferation and decrease the membrane fluidity.

Bone Neoplasms↗

PubMed2000

[Reevaluation of the nomenclature and diagnostic criteria in 477 patients with severe hepatitis].

OBJECTIVE: To explore the possibility of establishing more reasonable nomenclatures and diagnostic criteria for patients with severe hepatitis (SH) through analyzing clinical data of 477 cases of SH. METHODS: The clinical characteristics and outcomes of SH were analyzed according to different criteria. RESULTS: Chronic severe hepatitis (CSH) made up 88.5% of total cases of SH. The survival rate in the patients with hepatic encephalopathy was much lower than that without hepatic encephalopathy. About 1/5 of cases of subacute severe hepatitis (SSH) and CSH had neither ascites nor hepatic encephalopathy. When the period of 2 weeks was used in replace of 10 days for the diagnosis for acute severe hepatitis (ASH), the newly added cases were consistent with the characteristics of ASH. CONCLUSION: We suggest dividing SH into 2 types: encephalopathy and non-encephalopathy by using the nomenclature of fulminant hepatitis and severe type hepatitis, respectively. The late-onset form should be added besides of acute form and subacute form. It seems to use the period of 2 weeks as the new definition of onset time for ASH. The criteria of dividing SH into 3 forms, i.e. ascites, encephalopathy and ascites plus encephalopathy, and the nomenclature recommended by the International Association for the Study of the Liver Subcommittee are not satisfactory when used in clinical cases. The typing of CSH remains to be clarified.

Adolescent↗

PubMed2000

A comparative study of factors affecting chiral separations under reversed-phase conditions using cellulosic and Pirkle-type chiral selectors.

Limited studies have been conducted in reversed-phase chiral chromatography despite the relevance to water soluble chiral analytes. Systematic investigation and interpretation of factors affecting chiral separation in reversed-phase LC is crucial to efficient chiral method development. Two of the most useful chiral stationary phases (CSPs), a cellulosic (Chiralcel OJ-R) and a Pirkle-type (Chirex 3005), were chosen as the chiral selectors in this study to systematically investigate the factors affecting chiral separation of a series of Fmoc-amino acids. The effects of temperature, pH, buffer concentration, buffer type and organic modifiers on retention and chiral selectivity were compared between the cellulosic and the Pirkle-type selectors. Temperature affected retention and selectivity, as predicted by thermodynamics, using both types of chiral selectors. On the cellulosic CSP, buffer pH was the only factor which caused a significant change in chiral selectivity, while several factors, including buffer concentration and organic modifier type, affected chiral selectivity on the Pirkle-type CSP. The results also indicated that the cellulosic CSP had a retention mechanism analogous to conventional reversed-phase LC, however, the Pirkle-type selector appeared to show a mixed mode retention mechanism for these analytes.

Journal Article↗

PubMed2000

Relationship between expression of type III collagen and phenotype of vascular smooth muscle cells in neointimal of stented coronary artery.

OBJECTIVE: To investigate the secretive features of type III collagen in restenosis of the stented coronary artery and the relationship between the expression of type III. collagen and vascular smooth muscle cells (VSMCs). METHODS: An animal model of restenosis was established by implanting oversized tantalum stents into the coronary arteries in 26 dogs. At the 7th, 14th and 28th days after implantation, the stented coronaries were harvested. Transmission electronic microscopy and immunohistochemistry were employed to investigate the features of type III collagen secretion and VSMCs' phenotype. The expression of type III collagen was quantified and compared for the three stages. RESULTS: Migration and proliferation of VSMCs were the main features at the 7th day after injury. At the 14th day, proliferation of VSMCs reached the peak while much more secretion of collagen was noticeable. VSMCs began to transform from the synthetic phenotype to the contractile phenotype at the 28th day, when a great quantity of collagen was also secreted. The quantity of secreted type III collagen was greater at the 14th and 28th day than that at the 7th day (P < 0.05). The stain density of type III collagen was positively correlated to neointimal thickness at both of 14th and 28th day. CONCLUSION: The pathological bases of restenosis are variant in different period of restenosis formation. Type III collagen may play an important role in the late stage of restenosis after coronary stenting.

Animals↗

PubMed1999

Empirical relationship between chiral selectivity and mobile phase modifier properties.

An empirical relationship was derived which relates properties of the mobile phase modifier to the chiral selectivity factor for a given analyte/chiral selector combination. Using carbon dioxide and heptane-based mobile phases, the effect of various mobile phase modifiers on Pirkle-type stationary phases may be accurately modeled using a two-parameter equation. Similar results are obtained using cellulosic stationary phases with carbon dioxide-based mobile phases. Modeling separations performed using heptane-based mobile phases with cellulosic stationary phases were not successful. The predictive ability of this modeling approach was demonstrated using novel modifiers and chiral analytes.

Chromatography, Liquid↗

PubMed1999

[Management of destructive electrical burns of wrist].

OBJECTIVE: To reduce amputation rate of most severe pattern (Type III) of electrical burns of wrist. METHODS: Early wrist decompression followed by selective transfusion of dextran, PGE1, low molecule heparin to prevent thrombosis of injured radial and ulnar arteries, vascular bridging across the distal forearm and wrist to the hand soon after the appearance of circulatory failure to the hand. Free tissue transfer, especially the use of greater omentum and the innovated abdominal flaps, to repair the circumferential wounds of the wrists are recommended. RESULTS: A group of 102 limbs of 90 patients were treated in the last 10 years, among them the amputation rate of most severe pattern (Type III) of electrical burns of wrists was significantly reduced from 80% to 38.9% compared with 10 years before. CONCLUSION: A comprehensive treatment including the use of anticoagulation drugs, vascular reconstruction, sophisticated surgical repair of the wound are effective in reducing the amputation rate of electrical burns of wrists.

Adolescent↗

PubMed1998

[Experimental high-voltage electrical burns on limbs of rabbits].

OBJECTIVE: The study was designed to investigate the changes in some rheological parameters and ET-1 in venous blood following electrical burns. METHODS: One of the hind limbs of rabbits was subjected to 3000 V, 2.5 A charge of alternative electric current for 3 seconds. Rheological parameters such as red cell deformability (RED) and platelet aggregation rate (PAR), as well as endothelin-1 (ET-1) in venous blood drained from electrical burn wounds and contents of ATP in damaged muscle were measured at time intervals of 2 h, 24 h, 48 h and 72 h postburn. RESULTS: The changes in the parameters mentioned above were significant following electrical injury. The administration of PGE1 showed an advantageous effect in prevention of thrombosis and muscle "progressive necrosis" through improvement in RCD, reduction of PAR and the content of ET-1 in local circulation. CONCLUSION: RCD, PAR and the content of ET-1 in local circulation changed significantly following electric injury and may play an important role in the process of "progressive necrosis". The potential use of PGE1 in the treatment of electrical injury is proposed.

Alprostadil↗

PubMed1997

[Comparison of defibrase and heparin in the prevention of thrombosis after coronary intervention].

To evaluate the effects of defibrase on thrombosis after coronary intervention. 12 dogs were randomized into group to be treated with defibrase (n = 6) and another group with heparin (n = 6) after coronary intervention. After implanting stents in coronary arteries, canine platelets labeled with 99mTc-hexamethyl propylene amine oxime were re-transfused into blood circulation. The stenting vessels were imaged with gamma-camera in vivo and in vitro at the 4th and 24th hour, then the relative radioactivity of stenting vessels was quantified. The isolated stenting vessels were weighted and measured with gamma-counter and the number of deposited platelets was calculated. The relative radioactivity and the number of deposited platelets were lower in the group of defibrase than in the group of heparin (P < 0.01). Compared with heparin, defibrase has more potent effect on the prevention of thrombus formation and may reduce the early-reocclusion after coronary intervention.

Angioplasty, Balloon, Coronary↗

PubMed1991

[Effect of HFMC injection of various concentrations on patency of vas deferens and resumption of fertility in rats].

Great efforts have been made to develop non-occlusive or non-ever-lasting-occlusive contraception devices in vas deferens during the recent decade at home and abroad. In our previous studies both in vivo and in vitro, polymer HFMC was found to have a spermicidal effect. In this investigation in SD rats, the relationship between the concentration of HFMC injected into the vas deferens and the resumption of fertility was studied by means of continual observations on the existence of sperms in vaginal smears from the caged female and on pup-birth delaying, so as to determine occlusion of the vas lumen and the effect of HFMC on contraception in male. The histopathological changes in the vas deferens and caudal epididymis of the HFMC-injected male rats were also observed. The results indicated: (1) HFMC in concentration over 7.5% could show temporary contraception effect by its slow releasing of H+; (2) HFMC could induce definite contraception effect which lasted longer as the concentration of HFMC given increased; (3) HFMC had no effect on the descendents in number, mortality, sex ratio, body weight and appearance; (4) the bilateral internal reproductive structures were identified normal after resumption of fertility, but 20% HFMC induced vas deferens occlusion and spermatoceles; (5) moderate concentration of HFMC was considered favorable for reversible intra-vas deferens contraception.

Animals↗