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Biomedical subjects

B Yang

Publications and source records attributed to B Yang.

At least 181 records · Page 10Linked to original sources
PubMed1999

Bioactivities of nerve growth factor from Chinese cobra venom.

The nerve growth factor, NGF, from Chinese cobra Naja naja atra venom was isolated by gel-filtration and ion-exchange chromatography. Cobra NGF was characterized by analytical HPLC techniques as well as SDS-PAGE, and was proven to be a glycoprotein with a mol. wt. of 23 (+/- 2) kD and a pI of 9.2. The amino acid analysis and N-terminal sequencing were performed using conventional methods. Bioassays with cultured chick embryos ganglia and rat pheochromocytoma PC-12 cells revealed a promotion of fiber outgrowth, which is typical of NGF activity. Absence of enzymatic, toxicological, and teratogenic activities were shown by quality inspection. Since 1994, many clinical cases about volunteers receiving NGF treatment have been reported in mainland China. Bioactivities of NGF deal with a wide range of disciplines and technologies. In this paper we will discuss neuronal and non-neuronal effects of NGF treatment. Does the NGF cross the blood-brain barrier by transcytosis into the brain tissue? How is NGF important in wound healing, especially in peripheral nerve injury and diabetic neuritis? NGF may also be useful for male volunteers suffering from sterility, because it is possible that the sexual cells of testis can be promoted to maturity.

Animals↗
PubMed1999

Effects of anordrin, droloxifene, nomegestrol, and mifepristone on cultured rat luteal cell apoptosis.

AIM: To study the effect of four kinds of antifertility agents anordrin(Ano), droloxifene(Dro), nomegestrol (Nom), and mifepristone (Mif) on luteal cell apoptosis. METHODS: Cultured rat luteal cells were incubated with different agents. HE stain was used to observe morphological changes. Extracted DNA was electrophoresed on agarose gel. Apoptotic cells were quantitated by flow cytometry. RESULTS: All 4 drugs reduced cell viability. Dro induced apoptosis while the other 3 drugs induced necrosis. Typical DNA ladders were observed after cells were incubated with Dro and there were 15.4%, 75.4%, or 90.5% apoptotic cells after treatment with Dro 1.25, 2.5, or 3.75 mg.L-1, respectively. CONCLUSION: Dro induced apoptosis while Ano, Nom, and Mif induced necrosis in cultured rat luteal cells.

Animals↗
PubMed1999

[Comparative study on early revascularization of membranous and endochondral onlay bone grafts in the rat].

OBJECTIVE: To investigate the disparity in early revascularization of the membranous and endochondral bone grafts. METHODS: Twenty Wistar rats were randomly divided into two groups of 10 each. Full-thickness cranial (membranous) and split-thickness iliac crest (endochondral) onlay bone grafts were placed subperiosteally onto the snout of the animal without bony fixation. At 7 and 14 days after grafting the bone grafts together with the recipient sites were harvested. Revascularization was studied utilizing opacifying injection and computerized image analysis technique. RESULTS: The extent of vascularization at 7 days was 11.88% and 22.33% in membranous and endochondral bone grafts, respectively, and they developed to be 15.93% and 34.93% at 14 days, respectively. CONCLUSION: The results indicated that endochondral bone grafts were more rapidly revascularized than membranous bone grafts at 7 and 14 days (P < 0.05). Differences in graft architecture are theorized to account for the relationship between the vascularization and volume maintenance in the bones of different embryonic origin.

Animals↗
PubMed1999

[Histological study and stereologic analysis of membranous versus endochondral onlay bone grafts].

OBJECTIVE: The experimental study was to determine the differences in changes in the onlay bone grafts of different embryonic origin. METHODS: The study was designed to compare the potential for appositional bone growth in membranous and endochondral onlay grafts in New-Zealand rabbits and a rhesus monkey. Results were assessed with volumetric measurement, histological examinations and stereologic analysis with double-fluorochrome labeling technique. RESULTS: For the membranous and endochondral bone grafts, the volumetric retention rate was (78.4 +/- 3.5)% and (56.0 +/- 5.1)% respectively. The mineralization apposition rate (MAR) was (3.6 +/- 0.8) microns/d and (0.92 +/- 0.33) micron/d; the osteoid seam width (OSW) was (14.56 +/- 2.69) microns and (7.38 +/- 2.20) microns; the tetracycline uptake rate(TUA) was (91.22 +/- 2.69)% and (51.28 +/- 4.11)%, respectively. CONCLUSION: 1. It was found that the membranous bone graft maintained its volume to a significantly greater extent than the endochondral bone graft; 2. Membranous bone grafts exhibited higher survival rate and greater activity than endochondral bone grafts; 3. Different changes were also found in the two recipient sites. There was more powerful bone regenerative reaction in the recipient bed of the membranous bone graft than the endochondral one.

Animals↗
PubMed1999

MRI evaluation of bone marrow of normal lumbar vertebra in the Chinese: normal patterns and preliminary quantitative study.

OBJECTIVES: To establish the normal patterns of lumbar vertebral marrow in normal Chinese, to determine its normal value of relaxation times (T1 and T2), and to investigate the relationship between relaxation time and age or sex. METHODS: 320 of 1000 cases (sampled randomly) received MR imaging. According to the MRI findings of sagittal T1WI, marrow patterns were established. 268 cases were studied quantitatively (T1 and T2 measurements). RESULTS: The normal bone marrow patterns of lumbar vertebra were divided into four main patterns (six subgroups). The normal values of relaxation times (T1 and T2) were measured. T1 or T2 value decreased with aging. No significant difference in T1 value between two sexes (< 40 years old: u = 0.4307, P > 0.50; > or = 40 years old: u = 0.554, P > 0.05). No significant difference was seen in T2 value between two sexes before 40 years old (u = 1.3628, P > 0.10), but significant difference after 40 years old (u = 2.1498, P < 0.05). CONCLUSIONS: To establish the normal patterns of lumbar vertebral marrow and determine its normal values of relaxation times have important clinical value in the diagnosis of bone marrow diseases.

Adolescent↗
PubMed1999

[Randomized controlled prospective study of secondary prevention for primary liver cancer].

OBJECTIVE: To evaluated the effectiveness of secondary prevention for primary liver cancer (PLC). METHODS: This is a randomized controlled study. 18,816 Shanghai urban residents, aged 35-55, with serum evidence of HBV infection or chronic hepatitis were randomly assigned into the screening group (9,373) or the control group (9,443). In the screening group, participants were tested with serum AFP and real time ultrasound every 6 months, while in the control group, participants were not informed about the study and received no screening. Participants with positive results underwent a diagnostic evaluation, and all patients diagnosed as PLC were treated appropriately and followed up. RESULTS: After 5 years of study, there were 22,631.5 person-years screened. 86 patients with PLC were detected. 51 patients were detected in the control group within 32,944 person-years. In the screened group, 60.5% (52/86) of patients were in stage I, and 45.3% (40/86) with small liver cancer. However, there were no patients in stage I or with small liver cancer in the control group. The resection rates were 46.5% in the screened group, and 7.8% in the control group. The 1 to 5 years survival rates of PLC patients in the screening group were 65.0%, 65.0%, 52.7%, 52.7% and 52.7%, respectively, and in the control group were 30.0%, 6.5%, 0%, 0% and 0%, respectively. CONCLUSION: Screening can detect PLC in the early stage, and improve the prognosis of PLC, indicating that secondary prevention can decrease the mortality of PLC.

Adult↗
PubMed1999

Surgical treatment of hepatocellular carcinoma and related basic research with special reference to recurrence and metastasis.

OBJECTIVE: To summarize the progress of surgical treatment of hepatocellular carcinoma (HCC) and related basic research at the Liver Cancer Institute of Shanghai Medical University in the recent years, with special reference to recurrence and metastasis. METHODS: Published and unpublished update clinical and experimental data in the above-mentioned areas are summarized. RESULTS: Surgical resection has played an important role in improving prognosis of HCC, the 5-year survival were 63.4% for small HCC resection (n = 806), 39.6% for large HCC resection (n = 1061), 64.7% for cytoreduction (using hepatic artery cannulation and ligation) and sequential resection of initially unresectable HCC (n = 93), 56.0% for cytoreduction using transcatheter arterial chemoembolization (TACE) and followed by resection (n = 65), and 22.4% for hepatic resection with removal of tumor thrombi in portal vein (n = 103). Unfortunately, the 5-year recurrent rate after curative resection of HCC was up to 61.5%, which was mainly a result of intrahepatic "metastasis" and multicentric origin of HCC. Clinically, re-resection of subclinical recurrence yielded 56% of 5-year survival (n = 202); prevention of recurrence by transcatheter arterial chemoembolization (TACE) + Interferon, or LAK/IL-2 therapy have decreased 3-year recurrent rate from 33% to 11%-18%. In experimental aspect, metastatic human HCC model in nude mice (LCI-D20) and HCC cell line with metastatic potential (MHCC97) have been established; studies on HCC invasiveness in the molecular level revealed similar results that reported in other solid cancers, and small HCC showed slightly better biological characteristics as compared with large HCC; microvessel density (MVD) that reflecting angiogenesis adversely correlated with 5-year survival of small HCC; experimental interventions using antisense H-ras, bispecific antibody, BB94, as well as anti-angiogenic agents (TNP470, suramin, CAI, heparin, antisense VEGF, etc.) have been demonstrated to inhibit tumor growth and lung metastasis in nude mice model. CONCLUSIONS: Recurrence and metastasis are the major obstacle to further improve prognosis of HCC, studies should be conducted both in clinical and experimental aspects, "HCC invasiveness" will be the major target to be studied, particularly in the molecular level, and anti-angiogenesis will be one of the important approach.

Angiogenesis Inhibitors↗
PubMed1999

Quantitative analysis of TGF-alpha and EGFR mRNA in laryngeal carcinoma tissues.

OBJECTIVE: To elucidate the stimulating role of the growth factor autocrine loop in the carcinogenesis and development of laryngeal carcinomas. METHODS: The reverse transcription-polymerase chain reaction technique was applied, and with beta-actin as internal standard, TGF-alpha and EGFR mRNA in laryngeal carcinomas, macroscopically normal laryngeal mucosas adjacent to the tumor and in vocal cord polyps were quantitatively examined. RESULTS: The mRNA index of both TGF-alpha and EGFR in laryngeal carcinomas and adjacent mucosas was significantly higher than those in vocal cord polyps (P < 0.05). The index of TGF-alpha mRNA was significantly higher in laryngeal carcinomas than in mucosas adjacent to the tumor (P < 0.05). CONCLUSIONS: The autocrine system consisting of TGF-alpha and EGFR may play an important role in the very early stage of laryngeal carcinoma, or even when the tissue phenotypic alteration does not occur. The elevated TGF-alpha mRNA level may trigger a switch from genotypic alteration to the phenotypic. The results are expected to be a theoretical basis for the preventive chemotherapy of laryngeal carcinomas.

Carcinoma, Squamous Cell↗
PubMed1999

[A study on the effect of house dust mite on interleukin-10 secretion of peripheral blood lymphocytes in patients with allergic asthma].

OBJECTIVE: To investigate the relationship between interleukin (IL)-10 and allergic asthma, and the effect of antigen on IL-10. METHODS: The supernatant of cultured peripheral blood lymphocytes (PBLC) from 20 patients with allergic asthma and 20 normal subjects with different stimuli [home-dust-mite (HDM) or dexamethasone] was determined for IL-10, by means f enzyme-linked immunosorbent assay. RESULTS: (1) IL-10 was significantly decreased in asthma group, as compared with the control group (P < 0.01); (2) Less IL-10 was released in HDM-stimulated PBLC in asthma (P < 0.01); (3) IL-10 was obviously increased in dexamethason-stimulated whether in the asthma or in the control group. CONCLUSION: The diminished IL-10 production from PBLC could be related to asthmatic attack in patients with allergic asthma. Dexamethason might exert, at least, a part of anti-inflammatory activity by inducing IL-10 secretion of PBLC.

Adolescent↗
PubMed1999

[A clinical analysis of Mooren's corneal ulcer].

OBJECTIVE: To investigate the clinical characteristics and to compare the effects of several therapies of Mooren's corneal ulcer. METHODS: 550 consecutive in-patients with Mooren's corneal ulcer were clinically analyzed, including the age, sex, laterality of the eye, ulcer location, rate of perforation, cure rate of surgeries, recurrent rate, and the effects of conjunctiva excision, lamellar keratoplasty (LKP), LKP plus cyclosporin A eye drops. RESULTS: The average age of onset of the ulcer was 48.4 years old, the ratio of male to female was 1:0.74, bilateral disease occurred in 165 cases (30.0%) of whom 52 cases (31.5%) were in the younger group and 113 (68.5%) in the older group. There were 501 eyes (70.1%) with the ulcer located at the limbus of palpebral fissure, and 95 out of 715 eyes with the disease had corneal perforation, the rate of perforation being 13.3%, 41 cases (43.2%) in the younger group and 54 cases (56.8%) in the older group. The postoperative recurrent rate was 25.6%. The cure rate of once LKP plus cyclosporin A eye drops was 73.7%, the final cure rate was 95.6%, and the preservative rate of the corneal anatomical structure of the surgeries was 99.7%. CONCLUSION: LKP plus cyclosporin A eye drops is an effective treatment of Mooren's corneal ulcer.

Adolescent↗
PubMed1999

[RAPD analysis of germplasm in "baizhi"].

OBJECTIVE: To analyse the germplasm in Baizhi. METHOD: Using 12 random primers, over seventeen individuals' RAPD were detected in four populations from wild Baizhi (Angelica dahurica), Qi Baizhi and Hang Baizhi. RESULTS: A total of 40 loci were amplified, 26 of which were polymorphism(65%). The PPS values of Hang Baizhi and Qi Baizhi indicate their low levels of genetic diversity. According to the RAPDinstance analysis, the genetic distance(0.16) between Qi Baizhi and Hang Baizhi is shorter than that of the individuals of the populations of Qi Baizhi and Hang Baizhi, and all of these genetic distances are shorter than those between wild Baizhi and Hang Baizhi(Qi Baizhi). CONCLUSION: Hang Baizhi- and Qi Baizhi belong to the same taxon, which is different from the wild Baizhi.

Angelica↗
PubMed1999

[Morphological studies on 18 species of gualoupi].

OBJECTIVE: To gain a clear idea of the drug Gualoupi and its adulterants. METHOD: Collecting data and spot investigating in 30 provinces, cities and autonomous regions in China. RESULT: Gualoupi used as drug in China consists of 15 species of Trichosanthes, 1 species of Momordica, 1 species of Citrullus and 1 species of Adenia(Passifloraceae). CONCLUSION: The main commodity is the rind of T. kirilowii or T. rosthornii, and the main adulterant is the rind of T. hupehensis.

Drug Contamination↗
PubMed1999

[Histological studies on rinds of 18 species of Gualou].

OBJECTIVE: To make clear the histological characteristics of rinds for eighteen species of Gualou. METHOD: Observing the cross sections and separate divide of the rinds with light microscope. RESULT AND CONCLUSION: Of eighteen rinds of Gualou, each trichome on exocarp, wood fiber and thickness of ring of stone cell are different from one another, this distinction can be used to identify the different rinds of Gualou.

Citrullus↗
PubMed1999

[An approach to some problems on utilization of medicinal plant resource in China].

OBJECTIVE: To provide some reference for the research on the utilization of medicinal plant resources. METHOD: Based on a review of the achievements in utilizing medicinal plant resources, three aspects were discussed: the utilization and conservation of the endangered and rare medicinal plants; the research on the authenticity and superiority of medicinal plants; and the quality control and evaluation of medicinal plants. RESULTS: Although great achievements have been made, some problems still exist. CONCLUSION: The research on the development and utilization of medicinal plant resources has broad prospects.

Conservation of Natural Resources↗
PubMed1999

[Separation and determination of the ingredients of cold medicines by capillary electrophoresis with amperometric detection].

Determination and separation of three ingredients--chlorphenamine maleate, acetaminophen and vitamin C in cold medicines by capillary electrophoresis with amperometric detection were carried out. The effects of detection potential and organic modifier were extensively investigated. Separation efficiency could be improved by adding 1, 2-propanediol into buffer. On optimizing condition, chlorphenamine maleate, acetaminophen and vitamin C were separated satisfactorily and eluted within 12 min. The detection limits were 0.02, 0.08 and 0.01 mg/L respectively. The ingredients in several cold medicines were detected successfully. The recoveries of the samples were 94.2%-102.8%. The method is simple, rapid and highly reliable for routine analysis.

Acetaminophen↗
PubMed1999

[Establishment and identification of the monoepitopic monoclonal antibody of Plasmodium falciparum].

AIM: To prepare a monoepitopic monclonal antibody of Plasmoduim falciparum. METHODS: According to the theory of protein structure, a peptide with 6-9 residues representting the antigenicity of the original histidine-rich protein II (HRP-II) of P. falciparum was synthesized and used to immunize BALB/c mice after purity identification by capillary electrophoresis. RESULTS: Four hybridoma cell lines targeting a suitable peptide from pf HRP-II were obtained by using spleen embedment method and hybridoma technology. CONCLUSION: It is the first report to prepare a monoepitopic monoclonal antibody against original protein by selecting a suitable peptide from the primary sequence of protein.

Animals↗