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Biomedical subjects

H Zhuang

Publications and source records attributed to H Zhuang.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Mutation of hepatitis B virus DNA pre-C region in patients with primary hepatocellular carcinoma in Guangxi].

OBJECTIVE: To study the association between mutation of hepatitis B virus (HBV) pre-C gene and HBV infection in patients with primary hepatocellular carcinoma (PHC) but negative hepatitis B e antigen (HBeAg) in Guangxi Province, China. METHODS: Nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA Pre C region in sera collected from 16 patients with PHC in Guangxi, and then their HBV DNA nPCR products were sequenced by Sanger method. RESULTS: Sera in fourteen of 16 patients showed positive HBV DNA, with a positive proportion of 87.5% (14/16). One (C23) of them was positive for HBeAg; one (C24) was negative HBeAg, but with normal sequence in his Pre C region; two (C7, C14) were co-infected with HBV wild and mutant strains; and the remainder eight cases (C3, C4, C5, C8, C10, C11, C12, C13) were infected with mutant virus strains, but stop codon at codon 28 was only found in C4, C5 and C12. One case (C8) was co-infected with both HBV stop codon mutant and non-stop codon strains. CONCLUSION: It is uncommon for patients with PHC in Guangxi infected with HBV mutant strain with classical mutation at nt 1 896, which suggests that maybe there exist other types of mutation other than that in pre-C region causing HBV infection without HBeAg.

Base Sequence↗
PubMed2000

[Genotyping of hepatitis C virus and homology analysis of its core gene sequences isolated from different geological regions].

OBJECTIVE: To study the structure of its genotypes and gene variation of hepatitis C virus (HCV) isolated from different geological regions. METHODS: Serum specimens were collected from patients with HCV infection of Henan and Hebei Provinces of China, as well as of Sweden and Germany. HCV RNA in their serum was detected by retro-transcription polymerase chain reaction (RT-PCR) and genotyped. The core gene of 11 HCV isolates were sequenced and their homology was analyzed for different geographic regions with software. RESULTS: Structure of HCV genotypes, isolated from two provinces of China, and from Sweden and Germany, was not identical. The homology of their core gene sequences of the same HCV genotype isolated from the same region was higher than that from different regions, and subtypes 1b and 2a were found in serum collected from China and subtypes 1a, 2c and 3a in serum from Sweden and Germany. CONCLUSION: Structure of HCV genotypes associated with their geographic distribution and difference in sequences of the same HCV genotype also associated with their geographic regions.

Base Sequence↗
PubMed2000

[Analysis of hepatitis G virus genotypes in some areas of China].

OBJECTIVE: To study the genotype distribution of hepatitis G virus (HGV) isolated from different population in some areas of China. METHODS: A total of 12 strains of HGV were isolated from different areas of China (three from Guangxi Zhuang Autonomous Region, three from Hebei Province, one from Heilongjiang, Jiangxi, Guangdong, Jiangsu, Anhui, Jilin Provinces and Xinjiang Autonomous Region each). The HGV 5' untranslated region (UTR) of the 12 isolates was sequenced and compared with other 26 isolates previously reported (17 from China and nine from other countries). RESULTS: The nucleotide sequences of five HGV clones isolated from the same patient with HGV infection were identical, with the homology of 99.1% - 100%, indicating that variation of HGV in the same human body was very limited. Genotyping could be based on the sequence of one positive clone isolated from a patient with HGV infection. The homology of the nucleotide sequences in the 12 isolates was 96.8% - 99.4%, suggesting that they belonged to the same genotype. The homology of the 12 isolates was 88.0% - 89.7%, 87.2% - 90.3% and 94.7% - 96.3%, respectively, as compared with HGV genotypes 1 (U36380), 2 (U44402) and 3 (D90601), which indicated that all the 12 HGV isolates belonged to genotype 3. Phylogenetic distance analysis of the 38 isolates suggested that HGV strains isolated from China could be further divided into different subgroups. CONCLUSION: The majority of Chinese HGV isolates belonged to genotype 3 and they could be further divided into different subgroups.

Base Sequence↗
PubMed2000

[IR and Raman studies of inorganic nano giant cluster compounds].

The syntheses, IR and Raman spectra of four nanosize giant cluster compounds were reported in this paper. These compounds show similar IR and Raman spectra because they were assembled by the similar building blocks. The bands with frequencies in IR spectra in the range from 980 to 550 cm-1 and those absorptions under 970 cm-1 in Raman spectra have to be attributed to the absorptions of Mo-O bonds including Mo = O, Mo-O-Mo and mu 3-O-Mo bonds.

English Abstract↗
PubMed2000

[A new chemiluminescence immunoassay method for the determination of cancer embryo antigen].

A new chemiluminescent probe 10,10'-dimethyl-3,3'-disulfo-9,9'-biacridine DMDSBA) is used to label anti-CEA antibody, the molar incorporation is 1.15-1.32 mole of DMDSBA per mol anti-CEA; the conditions of labeling reaction, sandwich immunoassay and chemiluminescent reaction are studied. Moreover, a new double antibody sandwich chemiluminescence immunoassay is firstly established, the linear calibration ranges is 1.5-150.0 ng.mL-1 and the detection limit is 0.53 ng.mL-1. This method is used to detect cancer embryo antigen (CEA) in human serum, the results are well-matched with that of radio immunoassay.

Carcinoembryonic Antigen↗
PubMed1999

Use of Dicalcium Phosphate Dihydrate as a Probe in an Approach for Accurate Calculations of Solution Equilibria in Buffered Calcium Phosphate Systems.

Both synthetic and biological carbonated apatites have been shown to possess metastable equilibrium solubility (MES) distributions. Investigation of their MES behavior requires accurate knowledge of the activities of the relevant ions over a range of solution compositions. This in turn requires that the activity coefficients for these ions and the stability constants for the various solution complexes be accurately known. Since the solubility of dicalcium phosphate dihydrate (DCPD) can be easily determined, it can be used as a probe to study the appropriateness of proposed sets of stability constants and activity coefficients. In the present study, the solubility of DCPD was determined in acetate buffer solutions at pHs ranging from 4.5 to 6.5 and this allowed for the determination and evaluation of the stability constants of the NaHPO(-)(4), CaHPO(0)(4), CaH(2)PO(+)(4), and CaAc(+) complexes. The activity coefficients were calculated by a modification of the extended Debye-Hückel method and also by Bockris and Reddy's method, in which the activity of water and the hydration numbers of ions are also considered. The solution conditions were controlled to simulate the dissolution media used for the determination of MES distributions of apatites in our laboratory. Both methods of activity coefficient determination gave very consistent DCPD solubility product (K(DCPD)) values, and values for the stability constants of the relevant complexes determined using the two methods were close to each other. This approach of determining the stability constants under a set of conditions similar to those in apatite dissolution studies offers an effective set of parameters which, though not necessarily always exactly correct in absolute terms, are internally consistent and should allow for the quantitative characterization of the MES behavior of apatites. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Metastable Equilibrium Solubility Distribution of Carbonated Apatite as a Function of Solution Composition.

Previous studies have shown that carbonated apatites (CAPs) exhibit the phenomenon of metastable equilibrium solubility (MES) in weak acid media. The purpose of the present investigation was to examine two questions: first, whether the MES concept is applicable to a broader range of solution conditions and, second, whether a driving force function associated with a surface complex having a constant stoichiometry governs the dissolution of CAP and, if so, what is this stoichiometry. CAP preparations with carbonate contents of 1.8-5.7 wt% (synthesized by hydrolysis of dicalcium phosphate anhydrate in solutions of varying bicarbonate levels or by direct precipitation from supersaturated calcium/phosphate/carbonate solutions) were studied as follows. MES distributions for each of the CAP preparations were determined by equilibrating the CAP under stirred conditions in a series of acetate buffers (0.10 M) containing various levels of calcium and phosphate in the pH range 4.5-6.5 and a solution calcium/phosphate ratio in the range 0.1-10. The amount dissolved in each instance was regarded as the fraction of the CAP possessing an MES value greater than that corresponding to the ion activity product (IAP) of the equilibrating solution. The solution IAPs were calculated from the solution compositions using plausible calcium phosphate stoichiometries, viz., dicalcium phosphate dihydrate, octacalcium phosphate, tricalcium phosphate, hydroxyapatite, carbonated apatite (based on the bulk composition of the particular CAP involved in the experiment), and tetracalcium phosphate. The fraction of CAP dissolved was plotted against the solution IAPs for each experimental set using each of the six assumed stoichiometries for the surface complex. The results demonstrated that the MES concept was applicable to all of the CAP preparations in media of various solution compositions and different pH levels. The most important new outcome of this study was that MES profiles for each of the CAP preparations in all of the experiments were found to be superimposable when solution IAPs were calculated using the hydroxyapatite stoichiometry, while such was not the case when other stoichiometries were used to calculate the solution IAPs. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Relationships among carbonated apatite solubility, crystallite size, and microstrain parameters.

The use of the metastable equilibrium solubility (MES) concept to describe the solubility properties of carbonated apatites (CAPs) and human dental enamel (HE) has been well established in previous studies using a range of CAPs with varying carbonate contents and crystallinities. It was shown in these studies that the mean value of the CAP MES is directly related to the broadening parameter full width at half maximum (FWHM) of the 002 reflection of the X-ray diffraction profile. The apparent solubility of the CAPs increased monotonically with an increase in the broadening of the diffraction peaks, and when this peak broadening was taken into account, carbonate had no additional effect upon the MES. The broadening of the diffraction peaks has been used as an indicator of crystallinity, and is generally influenced by both crystallite size and microstrain. The purpose of the present study was to extract the crystallite size and microstrain parameters separately from the X-ray diffraction peaks and then to determine their relationships to the corresponding MES values. The samples studied were CAPs synthesized by precipitation from Ca(NO3)2 and NaH2PO4 solutions in carbonate containing media at temperatures of 95, 80, and 70 degrees C, and powdered HE. The crystallite size and microstrain parameters were determined simultaneously with the refinement of the structural parameters with the Rietveld method of whole-pattern-fitting structure-refinement. A modified pseudo-Voigt function was used to model the observed peak profiles. The MES distributions for the CAPs and HE were determined by a previously described method. The results of this study showed that the CAPs possessed an MES distribution and therefore provided further support that MES distribution is a common phenomenon, regardless of the method of CAP synthesis. The crystallite size decreased and the microstrain increased with increasing carbonate content and decreasing temperature of synthesis of the CAPs. A plot of the mean of the MES distribution versus the microstrain parameter showed that the apparent solubility of the CAPs and HE correlated very well with the microstrain parameter. On the other hand, a plot of the mean of the MES distribution versus the crystallite size parameter showed a poor correlation between MES and crystallite size. These findings support a view that microstrain, rather than crystallite size, is the dominant factor governing the effective solubility of the CAPs and dental enamel.

Apatites↗
PubMed1999

[Serological character of hepatitis E virus mutants].

OBJECTIVE: 64 sera with serologically negative nonA-E were tested for HEV RNA and their serological characteristics were studied. METHODS: HEV RNA was tested by a reverse transcriptase PCR(RT-PCR) and the positive PCR products were cloned and sequenced. Of 15 patients positive for HEV RNA, 6 were followed up and tested for anti-HEV. RESULTS: 15 of them(23.4%) were HEV RNA positive. 9 of the 15 HEV sequences have 95% homology and the remaining 6 have only 80% homology as compared with the Chinese HEV strain at the nucleotide level. Of 15 patients positive for HEV RNA, 6 were followed up. 3 of 4 patients infected with typical HEV had anti-HEV seroconversion 1 month after infection and 2 patients infected with HEV mutants were persistently negative for anti-HEV 1 or 3 months after infection. CONCLUSION: The Commercial anti-HEV EIA Kit can not detect HEV mutants.

Hepatitis Antibodies↗
PubMed1999

[Study of surgical depilation in pig and human body].

OBJECTIVE: The study is to show how much dermis and the follicles within it should be removed in order to prevent hair regeneration. METHODS: The experiment used Wuzhishan mini pigs. Different thickness of the pig's dermis and the follicles within it were removed to observe hair regeneration. According to the result, the dermis and the follicles were removed from the scalps of 62 patients from Jan. 1995 to Dec. 1996. Subsequent hair regeneration was observed. RESULTS: Using surgical depilation to remove 1/4-2/5 thickness of the scalp dermis and the follicles within it stopped most of the hair regeneration. The rate of hair regeneration was 10-30%. Satisfactory clinical effects were achieved. CONCLUSION: Surgical depilation is a simple, effective, cheap way for hair removing.

Adolescent↗
PubMed1999

[A preliminary study on hepatitis E virus antibody IgG and IgM for the diagnosis of acute hepatitis E].

OBJECTIVE: To evaluate the significance of hepatitis E virus antibody (anti-HEV) IgG and IgM for the diagnosis of acute hepatitis E. METHODS: Acute phase sera from a total of 143 patients with sporadic hepatitis E in 7 cities of China were determined for anti-HEV IgM and IgG by using an enzyme-linked immunosorbent assay (EIA). 359 serial sera of 56 patients with hepatitis E and 68 serial sera of 4 rhesus macaques experimentally infected with hepatitis E virus (HEV) were also detected for anti-HEV IgG and IgM. RESULTS: In the 143 patients the positive rate of anti-HEV IgG was 100.0%, which was significantly higher than that of anti-HEV IgM (73.4%, 105/143). 97.2% of anti-HEV IgG positive patients had a titer over 1:40. The positive rate of anti-HEV IgM increased with the titer of anti-HEV IgG in sera. It was 0% (0/4), 44.4% (8/18) and 80.2% (97/121), respectively in patients with the anti-HEV IgG titer of 1:20, 1:40 and >or=1:80 (P < 0.001). All the anti-HEV IgM positive patients were also anti-HEV IgG positive. No patients were found to be anti-HEV IgM positive alone. Anti-HEV IgG was detected as early as 2 days after onset of the disease, with a cumulative positive seroconversion rate of 100% by 1 month. The negative seroconversion rate of anti-HEV IgG increased with course of the disease and 43.3% of the patients lost their anti-HEV IgG by 6 months after illness. Though anti-HEV IgM also seroconverted at the same time as anti-HEV IgG, its cumulative positive seroconversion rate was only 71.4% and declined rapidly. Up to 37.5% of anti-HEV IgM positive patients became negative by 1 month after onset. Similar antibody responses were observed in 4 rhesus macaques experimentally infected with HEV. CONCLUSION: It is suggested that as a result of the poor sensitivity of currently available anti-HEV IgM EIA kits, anti-HEV IgG will be a more reliable marker for the diagnosis of acute hepatitis E as compared with anti-HEV IgM.

Acute Disease↗
PubMed1999

[Treatment of benign prostatic hyperplasia with laser through the endoscope].

OBJECTIVE: To evaluate the effect of transurethral laser prostatectomy (TULP) and its relation with the size of prostate. METHODS: 469 benign prostatic hyperplasia receiving TULP from 1988 to 1998 were reviewed retrospectively, and the methods of operation and preoperative and postoperative symptom were compared. The effect of 233 patients undergoing TULP was compared with the size of the prostate. RESULTS: The average value for IPSS of 469 patients decreased from 26.7 (preoperation) to 14.2 (postoperation). The mean value of maximum uroflow rate increased from 6.2 ml/s (preoperation) to 11.8 ml/s (postoperation). No difference was seen in postoperative effect between the transurethral contact and noncontact laser prostatectomy. If the estimating weight of prostate exceeded 50 g, the maximum flow rate after 3 years was decreased evidently, the value of IPSS increased to over 20. CONCLUSIONS: If the estimating weight of prostate is less than 50 g, TULP is indicated.

Aged↗
PubMed1999

[Immunocyte reaction in stage III nasopharyngeal carcinoma in relation to biological findings and prognosis].

OBJECTIVE: To study the relationship between macrophages (MP), Langerhans cells (LC), T and B lymphocytes, biological behavior and prognosis of stage III nasopharyngeal carcinoma (NPC) patients. METHODS: 43 cases with stage III NPC were studied by immunohistochemical SP staining methods. RESULTS: The positive expression rates of infiltrating LC and/or MP in NPC were 41%, 65% (CD68+), 46% (lysozyme+), and were related to prognosis, but not to age, sex, metastasis to cervical lymph nodes and basi-cranial destruction and/or cranial nerve damage. In addition, infiltrating T or B cells in NPC were not related to the prognosis or biological behavior. However, when both infiltrating T lymphocytes and LC and/or MP were marked, the prognosis of these cases were better than that of those cases whose infiltrating LC and/or MP were marked but T cell infiltration was scarce. CONCLUSION: The prognosis of stage III NPC is related to LC or MP, survival is especially longer in those with marked T cell infiltration.

Adult↗
PubMed1999

[Clinical significance of Q-Tc dispersion after exercise in aged patients with old myocardial infarction].

OBJECTIVE: This study was aimed to evaluate clinical significance of Q-Tc dispersion after exercise in aged patients with old myocardial infarction. METHOD: Sixty-four aged patients with old myocardial infarction(infarction group) were examined by treadmill exercise, dynamic electrocardiography, echocardiography, and were followed up for average of 24.12 +/- 7.7 months. 30 healthy aged persons were served as control group. RESULTS: Compared with that (40.21 +/- 15.21 ms) before exercise, Q-Tc dispersion (59.37 +/- 20.17 ms) was increased significantly after exercise in infarction group(P < 0.01). But no significant difference was found in Q-Tc dispersion of control group before and after exercise(34.70 +/- 12.29 ms vs 38.91 +/- 13.62 ms P > 0.05). In infarction group, occurrence of abnormal contraction of left ventricular wall, aneurysms, NYHA III class and > III class of Lown's ventricular arrhythmia classification was significantly higher in Q-Tcd > 50 ms patients than that in Q-Tcd < 50 ms ones(P < 0.05). It was found that 5 patients died of cardiac sudden death in Q-Tcd > 50 ms patients and no one died of cardiac sudden death in Q-Tcd < 50 ms ones. CONCLUSION: The Q-Tc dispersion after exercise is an important index to predict ventricular arrhythmia and cardiac death in the patients with old myocardial infarction.

Aged↗
PubMed1999

[Detection of 8-hydroxyguanine in the DNA of the H2O2-treated HL-60 cells by GC/FID].

This paper describes the DNA damage by hydrogen peroxide in HL-60 cells and the detection of 8-hydroxyguanine produced. The number of cells was at least about 2 x 10(7)/sample. Treatment of HL-60 cells with 0.4 mmol/L hydrogen peroxide for 24 h would result in DNA damage. The DNA samples were isolated, then qualitatively and quantitatively analyzed before hydrolysis. The results of experiments showed that 100-300 microL 98% formic acid could hydrolyze about 0.12 mg DNA samples completely in 150 degrees C for 1 h. After lyophilizing the DNA samples for 6-8 h, one DNA sample was trimethylsilylated completely with 150 microL BSTFA in 150 degrees C for 1 h. The recovery of trimethylsilylated 8-hydroxyguanine was 81.70%. The trimethylsilylated 8-hydroxyguanine was identified by GC/FID and CGC/MS-SIM parallely.

Chromatography, Gas↗
PubMed1999

[Surgical management of subglottic carcinoma].

OBJECTIVE: To explore the clinical features and the methods of surgery and functional restoration of subglottic carcinoma. METHODS: Thirteen cases with primary subglottic carcinoma were treated surgically in this department from 1981 to 1997. Among them, six had T1-2N0 lesions, one had T3N0 lesion and six had T3-4N1-2 lesions. Four cases underwent total laryngectomy and nine had subglottic partial laryngectomy. The extensive subglottic partial laryngectomy was performed on patients with tracheal invasion. The defects of larynx were reconstructed by using unilateral or bilateral pedicled musculocutaneous flap, myofascial flap accordingly. T-shape silastic tube was placed in to the reconstructed cavity of larynx during the operation and the patients were decannulated in 2 to 6 months. Unilateral radical neck dissection was performed on 4 patients and bilateral on 2. RESULTS: All cases had restored the function of phonation except for 4 who underwent total laryngectomy. Five out of 9 (55.6%) were decannulated. The swallowing function was restored in all patients. The 3-year and 5-year survival rates were 100% and 66.7% in the cases with total laryngectomy, 88.9% and 75.0% with subglottic partial laryngectomy, respectively. CONCLUSION: It is possible to detect early subglottic carcinoma by using fiberoptic laryngoscopy routinely with the combination of stroboscopy, CT, MRI in male patients over 40 with hoarseness. It is practical that the whole or partial function of larynx could be restored in most cases with subglottic carcinoma after partial laryngectomy or subtotal laryngectomy. Unilateral or bilateral neck dissection should be performed on patients with T3 or T4 lesion. Postoperative radiotherapy is necessary.

Adult↗