[Etiological study on patients with seronegative viral hepatitis]

OBJECTIVE

To investigate the etiology of hepatitis patients who were seronegative for viral hepatitis A through E.

METHODS

By using PCR, HBV DNA, HCV RNA, HEV RNA and HGV RNA were detected in sera of 104 patients with seronegative viral hepatitis. The partial nucleotide sequences of 2 HCV and 17 HEV isolates were analysed by direct sequencing.

RESULTS

Among the 104 patients with seronegative viral hepatitis, the positive rates of HBV DNA, HCV RNA, HEV RNA and HGV RNA were 29.8%, 3.8%, 22.1% and 7.7%, respectively, with only 38 cases (36.6%) negative for the genome of all known hepatitis viruses.

CONCLUSION

In addition to serological tests, the polymerase chain reaction of all known hepatitis viruses should be used to make the diagnosis of non-A - E hepatitis.

[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.

[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.

Multiple intraabdominal soft-tissue masses in a man awaiting liver transplantation: a case study and discussion

An unusual cause of abdominal soft-tissue masses is accessory splenic tissue. The Tc-99m-sulfur colloid liver-spleen scan is a valuable adjunct in making this diagnosis. This report describes a 47-year-old man who had an abdominal magnetic resonance imaging (MRI) scan as part of a pretransplant evaluation and was found to have multiple soft-tissue masses in the posterior aspect of his abdomen. His history was pertinent for a traumatic rupture of the spleen at the age of 12 years, for which he required a splenectomy. He had no symptoms or physical findings to indicate a lymphoproliferative disorder or other malignant process. His peripheral blood smear was remarkable for the absence of Howell-Jolly bodies. The nuclear scan confirmed the presence of uptake in the soft-tissue masses seen on MRI scan. This finding supports our diagnosis of splenosis in a man with a history of traumatic splenic rupture as a child.

[Brain hypometabolism in patients with mesial-temporal sclerosis demonstrated by FDG-PET]

The purpose of this study was to evaluate the extent of brain hypometabolism in patients with mesial-temporal sclerosis (MTS).

METHOD

This retrospective study included 21 patients who had medically refractory complex partial seizures and were selected for surgical therapy after a comprehensive evaluation which included surface EEG recordings and neuroimaging studies (PET, SPECT and MRI). All patients were subjected to surgical intervention and had an histopathological confirmation of MTS. A semi-quantitative analysis of the PET images was performed using regions of interest in the following structures: frontal, parietal and occipital lobes, basal ganglia, thalami, cerebellum and three different regions in the temporal lobes, which included medial, inferior and lateral cortices. An asymmetry index (AI) was calculated, comparing the counts per pixel in the homologous structures in both brain hemispheres. The AI of the different structures were then correlated.

RESULTS

A significant correlation was demonstrated between the AI of the medial temporal cortices and the frontal lobe, parietal lobe, basal ganglia and thalami (r = 0.72, 0.62, 0.47 and 0.47 respectively with p < 0.05 ). Within the temporal lobe, highly significant correlations were demonstrated among the structures (as high as 0.86 between temporo-medial and temporo-inferior).

CONCLUSION

These data indicated that hypometabolism extends beyond the epileptogenic focus in the temporal lobe in patients with complex partial seizure related to MTS. The metabolism in the medial portion of the temporal lobe is more correlated with the metabolism in the frontal lobe than with those of the others brain structures outside the temporal lobe. The pathophysiological mechanisms of hypometabolism remain controversial.

The role of positron emission tomography with fluorine-18-deoxyglucose in identifying colorectal cancer metastases to liver

Liver metastasis is a common consequence of colorectal carcinoma. Early and accurate detection of liver metastasis is crucial for a decision about partial hepatectomy, which is considered a standard and potentially curative therapy in such a setting. The presence of extrahepatic metastases will exclude surgical resection as a therapeutic option. Positron emission tomography with fluorine-18-deoxyglucose (FDG-PET) has been successful in detecting and staging a variety of malignancies. The purpose of this study was to assess the utility of FDG-PET in the accurate detection of liver and distal metastases from colorectal cancer. The results of 80 PET and computed tomography (CT) scans were compared with surgical pathology and clinical outcome. FDG-PET detected liver metastases in 28 patients, with a sensitivity of 100%. CT detected metastasis in 20 patients, giving a sensitivity of 71.4%. In addition, in one patient with negative CT findings, PET detected a focus of hypermetabolism in the region adjacent to liver, which was proven to be a second focus of primary colon carcinoma. In six patients with liver metastases, PET correctly detected extrahepatic lesions, while CT only detected hepatic lesions. In conclusion, FDG-PET is an excellent imaging modality for the detection and staging of liver metastases in patients with colorectal carcinomas.

Gene variation of 5'-NCR and core region in serum samples collected from patients with HCV infection

OBJECTIVE

To study the variation of HCV 5'-NCR and core gene in serial sera collected from patients with HCV infection.

METHODS

Serial sera were collected from 4 plasma-donors with HCV infection. 5'-NCR and core gene were amplified, sequenced and analyzed using software.

RESULTS

All the sequences obtained from the serial sera of patients with HCV infection were 1b and 2a subtypes. The variation of 5'-NCR only related to the genotype, and not associated with patients and time of serum collection. However, the sequences of core gene were not identical in HCV strains isolated from different patients. The sequences of those two regions of the same genotype isolated from the same patient did not change with time.

CONCLUSION

5'-NCR is more conserved than the core region and the genotype is the major cause of gene variation. No change in sequences of those two regions is found at the different points of time.

Standardized uptake value as an unreliable index of renal disease on fluorodeoxyglucose PET imaging

Fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography has been used extensively in the diagnosis of malignant conditions with high rates of sensitivity and specificity. However, increased FDG uptake is not limited to malignant tissue. In general, lesions with a mild degree of FDG uptake as measured by standardized uptake values less than 2.0 are considered benign, whereas those with values greater than 2.5 are usually regarded as malignant. Standardized uptake values in the kidney can be as high as 22 as a result of excretion of FDG through urine. Two cases are reported in which renal abnormalities could not be distinguished from urine based on standard uptake values alone.

[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.

Exclusion of chronic osteomyelitis with F-18 fluorodeoxyglucose positron emission tomographic imaging

PURPOSE

Excluding the diagnosis of chronic osteomyelitis is often difficult with noninvasive techniques, especially when bone anatomy and structure have been altered by trauma, surgery, or soft-tissue infection. It has been reported that fluorodeoxyglucose (FDG) positron emission tomography (PET) has excellent potential to diagnose osteomyelitis. In this study, the accuracy of FDG PET in the diagnosis of chronic osteomyelitis was determined.

METHOD

Twenty-two patients with possible osteomyelitis (5 in the tibia, 5 in the spine, 4 in the proximal femur, 4 in the pelvis, 2 in the maxilla, and 2 in the feet) who underwent FDG PET imaging and on whom operative or clinical follow-up data were available were included in this analysis. The final diagnosis was made by surgical exploration or clinical follow-up during a 1-year period.

RESULTS

FDG PET correctly diagnosed the presence or absence of chronic osteomyelitis in 20 of 22 patients. Six had chronic osteomyelitis and 16 proved to be free of osteomyelitis. FDG PET correctly identified all six patients with chronic osteomyelitis but produced two false-positive results. This study had a sensitivity rate of 100%, a specificity rate of 87.5%, and an accuracy rate of 90.9%.

CONCLUSION

FDG PET is a highly effective imaging method to exclude osteomyelitis when a negative scan result is obtained. However, positive results can be caused not only by true osteomyelitis but also by inflammation in the bone or surrounding soft tissues as a result of other causes. Overall, FDG PET may prove to be the preferred study in the management of patients with possible chronic osteomyelitis.

Solid-phase combinatorial synthesis using MicroKan reactors, Rf tagging, and directed sorting

A modular system for high-output solid-phase combinatorial synthesis has been designed and developed. The system employs three technological innovations to achieve its high efficiency and reliability: (1) application of microreactors as the reaction units in solid-phase synthesis; (2) use of radiofrequency tagging as the non-chemical tracking method; and (3) development of the directed sorting technology for split & pool synthesis. The system has been successfully applied in the synthesis of compound libraries of several hundred to several thousand compounds in multi-milligrams per compound quantity by many organizations.

[Clinical study on left ventricular diastolic heart failure in the aged patients]

Forty aged patients with LVDHF and 30 with left ventricular systolic heart failure (LVSHF), confirmed by radionuclide ventriculography were studied by clinical, echocardiography and treadmill test. Twenty healthy aged persons were served as control group. Compared with LVSHF, short duration and less severe manifestations of heart failure in LVDHF were observed. Compared with the control, left atrium was enlarged but not the left ventricular chamber, and LV wall was thickened in LVDHF, while enlargement of LV chamber was only found in LVSHF. However, LV systolic function was remained normal in LVDHF. The exercise tolerance was decreased in both LVDHF and LVSHF groups, but more marked in LVSHF.

[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.

Metastable Equilibrium Solubility Behavior of Carbonated Apatites in the Presence of Solution Fluoride

The aims of the present investigation were to assess the applicability of the metastable equilibrium solubility (MES) concept for the carbonated apatites (CAPs) over a range of pH and a wide range of solution fluoride concentrations and to examine the hypothesis that, in the presence of solution fluoride, a surface complex with the stoichiometry of fluorapatite (FAP) governs the MES behavior. Two CAP samples were prepared by precipitation from reaction media containing calcium nitrate (Ca(NO(3))(2).4H(2)O) and sodium phosphate (NaH(2)PO(4).H(2)O) at two different levels of sodium bicarbonate. The MES distributions of the two CAP preparations were determined by equilibrating approximately 10 mg of CAP powder in 2 L of 0.1 M acetate buffers (ionic strength=0.50 M) at pH 4.5 and 5.5 and at various levels of calcium, phosphate, and fluoride. The fluoride concentrations ranged from 0.03 to 12 ppm. From the compositions of the equilibrating buffer solutions, ion activity products based upon the stoichiometries of hydroxyapatite (HAP) and FAP were calculated in an attempt to determine the correct function governing the dissolution of the CAP preparations. The results of this study demonstrated that both CAP preparations exhibit the MES distribution phenomenon in solution media of varying pH and fluoride concentrations. Furthermore, the experimental MES data obtained with both CAP preparations at the lower pH (4.5) and at higher solution fluoride levels (>/=0.1 ppm) were essentially superimposable when plotted against the ion activity product based upon the stoichiometry of FAP, suggesting that in the presence of solution fluoride the MES governing surface complex may be an entity possessing a stoichiometry approximated by that of FAP. When the HAP stoichiometry was assumed to represent the surface complex, good superposition of the data was not possible. Copyright 2000 Academic Press.

Cloning of a T-type Ca2+ channel isoform in insulin-secreting cells

The T-type Ca2+ channel is an important determinant of electrical activity and of Ca2+ influx in rat and human pancreatic beta-cells. We have identified and sequenced a cDNA encoding a T-type Ca2+ channel alpha1-subunit derived from INS-1, the rat insulin-secreting cell line. The sequence of the cDNA indicates a protein composed of 2,288 amino acids that shares 96.3% identity to alpha1G, the neuronal T-type Ca2+ channel subunit. The transmembrane domains of the protein are highly conserved, but the isoform contains three distinct regions and 10 single amino acid substitutions in other regions. Sequencing rat genomic DNA revealed that the alpha1-subunit we cloned is an alternative splice isoform of alpha1G. By using specific primers and reverse transcription-polymerase chain reaction, we demonstrated that both splice variants are expressed in rat islets. The isoform deduced from INS-1 was also expressed in brain, neonatal heart, and kidney. Functional expression of this alpha1G isoform in Xenopus oocytes generated low voltage-activated Ba2+ currents. These results provide the molecular biological basis for studies of function of T-type Ca2+ channels in beta-cells, which is where these channels may play critical roles in diabetes.

[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.

[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.

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.

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.

[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.

[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.

[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.