Biomedical subjects

H Chen

Publications and source records attributed to H Chen.

At least 541 records · Page 30Linked to original sources

PubMed2000

[Childhood thyroid carcinoma: an analysis of 14 cases].

OBJECTIVE: To reveal the clinical characteristics, causes of misdiagnosis, treatment and prognosis of thyroid carcinoma in children. METHODS: Fourteen patients under 14 years of age with thyroid carcinoma were retrospectively reviewed. RESULTS: According to UICC's clinical and histopathologic classification (1989), there were 12 cases of papillary carcinomas (83.3%), 2 cases of follicular carcinomas (16.7%). All but one case were in stage I. Cervical lymph node metastasis was found in 12 cases (85.7%). Diagnosis was incorrect in 7 cases. All patients were operated, including unilateral neck dissection in 11 and bilateral neck dissection in 2. One patient received palliative subthyroidectomy and postoperative 131I treatment. In the follow-up period of 2 to 13 years (mean 6 years), no patient died. CONCLUSION: Thyroid cancer in children are mostly papillary carcinomas with good prognosis, regardless of high frequency of cervical lymph node metastases. Early cases can be picked up if misdiagnosis be avoided.

Adenoma↗

PubMed2000

[Reducing bacterial aerosols by ultrasonic scaling with Koutai or 1.5% H2O2 pre-rinse].

OBJECTIVE: To compare the effects of Koutai and 1.5% H2O2 on the bacterial aerosol contamination generated by ultrasonic scaling. METHODS: Aerosol and splatter produced by ultrasonic scaling were collected pre and post rinsing with Koutai or 1.5% H2O2, aerobes and anaerobes were incubated and counted. RESULTS: 737 CFU aerobes and 749 CFU anaerobes were deducted after rinsing with Koutai, 355 CFU aerobes and 419 CFU anaerobes were deducted after rinsing with 1.5% H2O2. Both groups are effective in reducing aerobes and anaerobes CFUs (P < 0.01), although the former was much better than the latter in the reduction of aerobic CFUs in aerosols (P < 0.05). CONCLUSION: Koutai or 1.5% H2O2 risen can significantly reduce aerobic and anaerobic CFU in aerosols.

Adult↗

PubMed2000

[Protective effects of tongli gongxia herbs on gut barrier in rat with multiple organ dysfunction syndrome].

OBJECTIVE: To explore the protective effects of Tongli Gongxia (TLGX) herbs on gut barrier with multiple organ dysfunction syndrome (MODS). METHODS: The MODS models were induced by intraperitoneal injection of Zymosan A, and Dachengqi decoction (DCQD) was used in treating MODS models. The levels of endotoxin in the peripheral and portal blood, and the contents of diamine oxidase (DAO), xanthine oxidase (XOD), malondialdehyde (MDA), reduced glutathione (GSH) and tumor necrosis factor (TNF), the permeability of intestinal mucosa and enterocytes, and the histopathologic changes were observed. RESULTS: The gut barrier function in MODS rats were severely damaged. DCQD could significantly reduce the levels of endotoxin in the blood (P < 0.01), the contents of XOD, MDA and TNF in the blood and intestinal tissue were lowered (P < 0.01), but the levels of GSH in blood and intestinal tissue were raised (P < 0.05). Levels of DAO in the intestinal tissue was markedly increased (P < 0.01). DCQD could reduce the permeability of intestinal mucosa and enterocytes, and attenuate the histopathologic changes of intestinal mucosa in MODS rats. CONCLUSION: TLGX herbs have apparently protective effects on the gut barrier in MODS rats.

Amine Oxidase (Copper-Containing)↗

PubMed2000

[Comparison on efficacy in treating liver fibrosis of chronic hepatitis B between Astragalus Polygonum anti-fibrosis decoction and jinshuibao capsule].

OBJECTIVE: To observe the efficacy of Astragalus-Polygonum Anti-Fibrosis Decoction (APAFD) and Jinshuibao capsule (JSBC) in treating liver fibrosis of chronic hepatitis B. METHODS: Ninety-two liver fibrosis of chronic hepatitis B patients were randomly divided into group A and B. Patients in group A received APAFD for 48 weeks, and in group B, they received JSBC for 48 weeks. The effects were observed on the change of hyaluronic acid (HA), laminin (LN), pro-collagen III (PCIII) and collagen IV (CIV) as well as liver functional tests and liver biochemical parameters before and after treatment. RESULTS: Levels of serum HA, LN, PCIII and CIV in the group A declined more obviously than that of group B, the difference was significant (P < 0.01). The liver functional tests such as total bilirubin (TB), alanine aminotransferase (ALT), albumin/globulin ratio, hepatitis related serum biochemical parameters such as cholylglycine (CG), serum ferritin (SF), prealbumin (PA) of group A all were improved more significantly than that of group B (P < 0.01). CONCLUSION: APAFD is more effective than JSBC in treating liver fibrosis of chronic hepatitis B, and in the inhibition of hepatic inflammation, it is a good composite Chinese herbal preparation against liver fibrosis.

Adolescent↗

PubMed2000

[Effect of hydroxyurea combined with interferon-alpha on growth and apoptosis-related oncogene expression of K562 cells].

OBJECTIVE: To observe the effect of hydroxyurea (HU) alone and in combination with interferon-alpha (IFN-alpha) on the cell growth and cell death, and the related oncogene expression of chronic myelogenous leukemia (CML) cell line, K562 cells. To further investigate the molecular basis of combination therapy on CML by chemotherapeutants combined with cytokines. METHODS: The proliferation and viability of K562 cells were detected by cell-counting and trypan blue dye exclusion test. The levels of bcr-abl, bax and c-myc gene expression in K562 cells incubated for 48 hours were examined using RT-PCR technique. RESULTS: proliferation was suppressed and cell death process was accelerated by both HU and HU combined with IFN-alpha. HU significantly inhibited bcr-abl gene expression and increased bax gene expression level (both P < 0.05 as compared with that of control). Furthermore, IFN-alpha dose-dependently enhanced the regulatory effects of HU on bcr-abl and bax gene expression. HU alone and in combination with IFN-alpha suppressed slightly c-myc gene expression. CONCLUSIONS: Both HU and HU combined with IFN-alpha can inhibit cell proliferation and promote cell death or apoptotic cell death by regulating the expression levels of the genes relating to cell proliferation and apoptosis. The molecular mechanism of HU and IFN-alpha synergistically acting on leukemic cells is further elucidated from the expression level of the related genes which control the balance of survival and death or apoptosis of the cells.

Apoptosis↗

PubMed2000

[Study on the FcepsilonRI-beta polymorphism and susceptibility of asthma in a Chinese population].

OBJECTIVE: To investigate the linkage between the polymorphisms of FcepsilonRI-beta gene and susceptibility of asthma in a Chinese population. METHODS: Thirty-two families with 192 samples and 122 cases of childhood asthma were studied. A coding variant of E237G was detected by PCR/XmnI restriction endonuclease digestion. Two RsaI polymorphic sites within non-coding region were tested by PCR/RsaI restriction endonuclease digestion. RESULTS: The allele frequencies for all three polymorphisms of FcepsilonRI-beta gene in the Chinese population were markedly different from those published results of Caucasians and Japanese. Comparing asthma family samples with normal control, we found that genotypes containing A allele within intron 2 polymorphic site were associated with asthma (P < 0.05, OR = 2.039). The level of total serum IgE showed significant difference among three genotypes of intron 2 polymorphic site (P < 0.05). The association between A allele and elevated total serum IgE was also significant (P < 0.05, RR = 1.361). We could not find any significant results from the other two polymorphisms, even in the coding variant E237G. CONCLUSION: We were unable to confirm that the FcepsilonRI-beta gene was crucial to the susceptibility of asthma and atopy and did not contribute substantially to variation in IgE levels from both sample groups.

Adolescent↗

PubMed2000

[Apoptosis induced by cisplatin and verapamil or SDZ PSC 833 in human ovarian cell lines].

OBJECTIVE: To study the pharmaceutical mechanisms of cisplatin (DDP), verapamil (VP) and SDZ PSC833, and the mechanism of developing acquired drug resistance. METHODS: Two ovarian carcinoma cell lines--one sensitive (COC(1)) and the other resistant (COC(1)/DDP) to cisplatin were used in this study. The cell viability was measured by trypan blue dye exclusion assay. The apoptotic cells were observed and distinguished by light and electron microscopy, and comet assay. Flow cytometry was used to measure the cell cycle. Six groups were set up according to drug(s) delivered: DDP, VP, SDZ PSC833, DDP and VP, DDP and SDZ PSC833, and control group. RESULTS: (1) VP or SDZ PSC833 enhanced cytotoxicity of DDP (q > 1, P < 0.01). (2) The most prominent effect of DDP on cell cycle kinetics was a slowdown in S-phase transit during which cells undergo apoptosis (P < 0.05). (3) COC(1) and COC(1)/DDP cells had different rates of apoptosis when DDP added. SDZ PSC833 enhanced apoptosis of COC(1)/DDP cells induced by DDP. CONCLUSIONS: VP and SDZ PSC833 increase sensitivity of the cell lines to DDP. SDZ PSC833 enhances apoptosis induced by DDP. Induction of apoptosis is one of the pharmaceutical mechanisms of DDP, and acquired drug resistance is associated with resistance to apoptosis. The most prominent effect of DDP on cell cycle kinetics is a slowdown in S-phase transit and apoptotic cells are at S-phase.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2000

[CO2 laser-microscopy technique in treating tumors near the sella turcica].

OBJECTIVE: To assess the laser-microscopy technique in dealing with tumors near the sella turcica. METHODS: Sixteen patients with tumors near the sella turcica who had been treated surgically by laser-microscopy technique from October 1996 to June 1998 in Haikou municipal hospital were analyzed retrospectively. RESULTS: In these patients, 11 patients had tumors bodies excised totally, and 5 had tumors bodies excised partially. All of then were followed up for 4 to 30 months. The curative effects were satisfactory. In 9 patients with defect in vision before operation, 6 showed obvious improvement, 2 moderate improvement, and 1 unmarked improvement. In 6 patients with endocrinopathy before operation, 4 returned to normal, and 2 showed improvement. In 4 patients with intracranial hypertension before operation, symptoms were retrieved. Only one patient who had diabetes insipidus after operation, and recovered after medication. CONCLUSIONS: CO(2) laser-microscopy technique the treatment of tumors near the sella turcica is advantageous: few accidental injuries because of its high-accuracy; less harassment to the hypophysis and subthalamus; less complication; small exposure of operative field; less bleeding and clear operative field; no stimulation of metastasis of carcinoma;and no interference of bioelectric current.

Adult↗

PubMed2000

[E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma].

OBJECTIVE: To study the significance of E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma (HCC). METHODS: Flow cytometry and immunohistochemistry were used to detect the expression of E-selectin and its ligand-sLeX in HCC cell lines and in human HCC tissues. RESULTS: The positive rate of E-selectin in vascular endothelial cells adjacent to cancer nest in tumors was 67.9% (19/28). In tumors accompanied with emboli or satellite foci, it was significantly higher than that without emboli or satellite foci (P < 0.05). The positive rate of E-selectin was not related to tumor size, tumor capsule, AFP, and the degree of differentiation. The positive expressions of sLeX in SMMU-7721, PLC/PRF/5 and HepGII cell lines were 7.03%, 63.35% and 97.29% respectively. The positive cells of sLeX were mainly distributed in the margin of tumors; the positive expression of sLeX in HCC cells in emboli or invasive tumor tissues was much higher than that in primary foci. CONCLUSION: E-selectin and its ligand-sLeX are closely correlated with the metastasis of HCC.

Adult↗

PubMed2000

[Expression of tumor metastasis gene MTA 1 in hepatocellular carcinoma: clinical implications].

OBJECTIVE: To evaluate the relevance of the expression of tumor metastasis gene metastasis-associated 1 (MTA 1) to HCC metastasis. METHODS: A fragment of MTA 1 cDNA was synthesized by reverse transcription (RT)-PCR. A DIG-labeled method of in situ hybridisation (ISH) was used to measure semiquantitatively MTA 1 mRNA in formalin-fixed, paraffin-embedded sections. RESULTS: Most of MTA 1 mRNA positive cells were located on the border of the tumor in some invasive HCC. High MTA 1 expression was found to correlate significantly with portal venous invasion, intrahepatic metastasis, tumor size or distant metastasis (P < 0.05), but not with gender, cirrhosis or AFP level. It also significantly predicted a shorter survival (P < 0.05). CONCLUSION: The overexpression of MTA 1 correlates closely with the invasion process of HCC.

Adult↗

PubMed2000

[Retinal detachment with anterior proliferative vitreoretinopathy and its surgical treatment].

OBJECTIVE: To explore the clinical characteristics and surgical results of retinal detachment in eyes with anterior proliferative vitreoretinopathy (PVR). METHODS: 83 patients (83 eyes) of retinal detachment with grade C-D PVR were studied. Different surgical methods were used in treating anterior PVR and posterior PVR, respectively. RESULTS: Among the 83 patients, anterior PVR was in 34 eyes (41.0%) and posterior PVR 49 eyes (59.0%). The anterior PVR occurred in younger patients, mean age 28.5 years, more in male patients (85.3%) and more in grade D of PVR (55.9%); in the posterior PVR, the mean age was 38.9 years, 63.3% of patients were male and 24.5% of patients were in grade D of PVR. Eighty-three patients had a mean postoperative follow-up of 12.9 months. Complete retinal re-attachment occurred in 24 eyes (70.6%) with anterior PVR and in 38 eyes with posterior PVR (77.6%; chi(2) = 0.51, P > 0.1). The final corrected visual acuity >or= 0.05 was in 11 eyes with anterior PVR (32.4%) and in 22 eyes with posterior PVR (44.9%; chi(2) = 1.32, P > 0.1). CONCLUSIONS: Eyes with anterior PVR have different clinical characteristics and worse surgical conditions when compared with eyes of posterior PVR. However, by the use of modern vitreoretinal surgery, the outcome in eyes with anterior PVR may become similar to that of posterior PVR.

Adult↗

PubMed2000

[Preventive effects of three kinds of inactive vaccines against epidemic hemorrhagic fever (EHF) after 5 years of vaccination].

OBJECTIVE: To observe the safety and the preventive effects of three kinds of vaccines as Mongolian gerbils kidney vaccine, mouse brains vaccine and hamster kidney vaccine inoculated 5 years ago. METHODS: Field study and laboratory tests were carried out by random grouping and IFAT, MCPENT, ELISA, HI tests. RESULTS: The antibody-dependent enhancement did not appear in all individuals who received vaccines after four or five years. The seroconversion rates of MCPENT were 8.97%, 11.76% and 18.75% while the seroconversion rates of IFAT were 20.73%, 30.22% and 23.40% respectively for Mongolian gerbils kidney vaccine, mouse brains vaccine and hamster kidney vaccine. The protection rates were 100% for all three kinds of inactive vaccines which showed good epidemiological efficacy. CONCLUSION: The vaccines can protect clinical infection of EHF effectively after four or five years of the initial vaccination.

Animals↗

PubMed2000

[Report on epidemic hemorrhagic fever (EHF) surveillance in 1999].

OBJECTIVE: To understand the epidemic tread of epidemic hemorrhagic fever (EHF) in 1999 and to develop programs for its control and prevention. METHODS: Epidemiological, zoo-epidemiologic, serologic and viral diagnostics were used to analyse the information of monthly and annual reports from surveillance spots. RESULTS: Twelve thousand nine hundred and thirty cases of EHF in all surveillance spots were reported with 135 cases of death in 1999. The morbidity and mortality were 5.37/100,000, and 1.04% respectively, which had a 1.47% decrease and 9.47% increase, comparing to that of 1998. The accordance of serological and clinical diagnosis was 67.25%, with rate of misreporting 1.28%. In animal surveillance, the density of mouse was 7.46% with predominant species Apodemus agrarius. In residential areas, the density of mouse was 6.21%, with predominant species Rattus norvegicus. For Apodemus agrarius in fields and Rattus norvegicus in residential areas, the indexes of HV carrier were 0.032 and 0.031 respectively in 1999. In spring and autumn, the indexes of HV carrier in Rattus norvegicus were apparently higher than that of Apodemus agrarius as the indexes of HV carrier in Rattus norvegicus were 0.028 and 0.036 comparing with 0.026 and 0.020 in Apodemus agrarius. CONCLUSION: It is suggested that more attention should be paid to the surveillance in low and medium-sized epidemic areas because northern China is dry with short rainy season while the epidemic situation in the serious epidemic areas had been under control to some degree.

Animals↗

PubMed2000

[Effects of IFN-alpha combined with IL-6 on cell growth and related genes expression and apoptosis of bone marrow cells from CGL patients].

OBJECTIVE: To investigate the effects of interferon-alpha (IFN-alpha) and IFN-alpha combined with interleukin-6 (IL-6) on cell growth and bcr/abl, bcl-2 and c-myc genes expression in the bone marrow mononuclear cells (MNC) from chronic granulocytic leukemia (CGL) patients. METHODS: MNCs were cultured in liquid medium at the presence of IFN-alpha (200 U/ml) or IFN-alpha (200 U/ml) plus IL-6 (100 ng/ml). The viable cells were counted and the expression levels of beta-actin, bcr/abl, bcl-2 and c-myc genes were quantitatively detected by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: The cell growth was markedly inhibited by IFN-alpha, but the extent of the inhibition was slightly decreased when IFN-alpha combined with IL-6. The expression levels of bcr/abl and bcl-2 gene were reduced by IFN-alpha or IFN-alpha plus IL-6. The expression of c-myc gene was inhibited by IFN-alpha but promoted by IL-6. CONCLUSIONS: Both IFN-alpha and IFN-alpha plus IL-6 can inhibit the expression of anti-apoptosis genes, and modulate the expression of c-myc. It is the possible mechanism of IFN-alpha therapy for CGL in chronic phase.

Adolescent↗

PubMed2000

High density lipoproteins enhanced antiaggregating activity of nitric oxide derived from bovine aortal endothelial cells.

In the present study, the effect of high density lipoproteins (HDLs) on the antiaggregating activity of nitric oxide (NO) derived from endothelial cells was investigated with the use of cultured bovine aortal endothelial cells (BAECs). The BAECs were placed in an aggregometer in contact with rabbit platelets after blocking cyclo-oxygenase with acetylsalicylic acid. Under this circumstance, the antiaggregating effect of endothelial cells was exclusively dependent on the release of NO, which was further confirmed by prevention of antiaggregating activity of BAECs with 1 mmol/L N(G)-Nitro-L-arginine. When this system was used, thrombin (0.1 U/ml) evoked 67.33+/-7.52% aggregation of rabbit platelets (2 10(8)/ml). This effect was inhibited by NO derived from endothelial cells (1 10(5) 1 10(6)/ml) in a cell number dependent manner. HDLs (1 mg/ml), added into the system immediately before BAECs, enhanced this antiaggregating effect of NO. However, incubating BAECs with HDLs for an hour and removing the HDLs by centrifugation did not have the same effect, unless HDLs were present during aggregation. No direct effect of HDLs on platelet aggregation was observed. The above findings suggest that HDLs can enhance the antiaggregating effects of BAECs mediated by direct interaction with NO.

Animals↗

PubMed2000

[Identification of Listeria species in 167 kinds of foods].

Through preliminary identification of isolation of Listeria species in six types foods, which consisted of 167 kinds of foods, we found both S-form and R-form colonies were suspected colonies of Listeria species, and some of them were catalase-negative, urease-positive, methyl red(MR) negative and Voges-Proskauer(VP) negative. The results showed that S-form, catalase-positive, urease-negative, MR-positive and VP-positive colony should not be used as the strict criteria for the identification of Listeria.

Animals↗

PubMed2000

[Effect of exposure to low concentration of benzene and its analogues on luteal function of female workers].

The effect of benzene and its analogues(BIA) on the luteal function of female workers was studied in a petrochemical corporation. The female workers from a chemical fiber corporation without benzene exposure were selected as controls. The levels of BIA(toluene and xylene) in the air at breathing zone were sampled and determined with gas chromatography(GC). The menstrual function was followed up. Urine pregnanediol-3-glucuronide (PdG) and follicular stimulating hormone(FSH) were measured by enzyme immunoassay(EIA). The results showed that BIA existed in low concentration in air. The exposure could lead to a shorter length of time of luteal phase(P < 0.05 or P < 0.01) and decrease luteal progesterone level (P < 0.05). It was suggested that the low concentration of BIA exposure could have effect on the luteal function in exposed female workers, and urinary hormones could be used as biomarker for the influences of benzene and BIA on reproduction.

Adult↗

PubMed2000

[Purification and identification of siderophore from Aeromonas hydrophila].

Siderophore of Aeromonas hydrophila(Ah) J-1 was purified from culture supernatant by polyamide column chromatography, eluted by double-distilled water, ethyl acetate precipitated, lyophilized, then the white powder was collected, and demonstrated by CAS and Arnow assay. The siderophore was phenolate, composed of 2,3-dihydroxybenzoic acid (2,3-DHB), lysine, glycine and tryptophan by HPLC. Being cultured iniron-deficient medium, the purified siderophore could stimulated the growth of Ah N9a which siderophore production is poorly positive and reverse the inhibition growth of EDDA. It suggested that siderophore could promote growth of bacteria and might play an important role in bacteria infection.

Aeromonas hydrophila↗