A splicing-dependent ER retention signal regulates surface expression of the mechanosensitive TMEM63B cation channel

TMEM63B is a mechanosensitive cation channel activated by hypoosmotic stress and mechanic stimulation. We recently reported a brain-specific alternative splicing of exon 4 in TMEM63B. The short variant lacking exon 4, which constitutes the major isoform in the brain, exhibits enhanced responses to hypoosmotic stimulation compared to the long isoform containing exon 4. However, the mechanisms affecting this differential response are unclear. Here, we showed that the short isoform exhibited stronger cell surface expression compared to the long variant. Using mutagenesis screening of the coding sequence of exon 4, we identified an RXR-type endoplasmic reticulum (ER) retention signal (RER). We found that this motif was responsible for binding to the COPI retrieval vesicles, such that the longer TMEM63B isoforms were more likely to be retrotranslocated to the ER than the short isoforms. In addition, we demonstrated long TMEM63Bs could form heterodimers with short isoforms and reduce their surface expression. Taken together, our findings revealed an ER retention signal in the alternative splicing domain of TMEM63B that regulates the surface expression of TMEM63B protein and channel function.

Distant coupling between RNA editing and alternative splicing of the osmosensitive cation channel Tmem63b

Post-transcriptional modifications of pre-mRNAs expand the diversity of proteomes in higher eukaryotes. In the brain, these modifications diversify the functional output of many critical neuronal signal molecules. In this study, we identified a brain-specific A-to-I RNA editing that changed glutamine to arginine (Q/R) at exon 20 and an alternative splicing of exon 4 in Tmem63b, which encodes a ubiquitously expressed osmosensitive cation channel. The channel isoforms lacking exon 4 occurred in ∼80% of Tmem63b mRNAs in the brain but were not detected in other tissues, suggesting a brain-specific splicing. We found that the Q/R editing was catalyzed by Adar2 (Adarb1) and required an editing site complementary sequence located in the proximal 5' end of intron 20. Moreover, the Q/R editing was almost exclusively identified in the splicing isoform lacking exon 4, indicating a coupling between the editing and the splicing. Elimination of the Q/R editing in brain-specific Adar2 knockout mice did not affect the splicing efficiency of exon 4. Furthermore, transfection with the splicing isoform containing exon 4 suppressed the Q/R editing in primary cultured cerebellar granule neurons. Thus, our study revealed a coupling between an RNA editing and a distant alternative splicing in the Tmem63b pre-mRNA, in which the splicing plays a dominant role. Finally, physiological analysis showed that the splicing and the editing coordinately regulate Ca2+ permeability and osmosensitivity of channel proteins, which may contribute to their functions in the brain.

The effect of aerobic exercise and Macrothele raven venom on tumor-bearing mice

Liver cancer is one of the most common cancers in the world. Macrothele raven venom, a complicated mixture of neurotoxic peptides, proteins and low molecular weight material, has antitumor properties, but its mechanism of action is unknown. Moderate exercise has been shown to shrink tumors and cause a remarkable reduction in the tumor growth rate. In this study, we examined the antitumor effect of Macrothele raven venom in combination with exercise on tumor-bearing mice. Our results demonstrate that aerobic exercise in combination with venom administered at different doses was much more effective in a mouse H22 hepatoma model compared to separate administration of the 2 treatments. The underlying mechanism of this effect may be related to the expression of various tumor suppressor factors.

[Evaluation of compounding EDTA and citric acid on remediation of heavy metals contaminated soil]

As commonly used eluents, Na2EDTA (EDTA) and citric acid (CA) have been widely applied in remediation of soil contaminated by heavy metals. In order to evaluate the removal of arsenic, cadmium, copper, and lead in the contaminated soil collected in a chemical plant by compounding EDTA and CA, a series of stirring experiments were conducted. Furthermore, the changes in speciation distribution of heavy metals before and after washing were studied. The results showed that, adopting the optimal molar ratio of EDTA/CA (1:1), when the pH of the solution was 3, the stirring time was 30 min, the stirring rate was 150 r x min(-1) and the L/S was 5:1, the removal rates of arsenic, cadmium, copper and lead could reach 11.72%, 43.39%, 24.36% and 27.17%, respectively. And it was found that after washing, for arsenic and copper, the content of acid dissolved fraction rose which increased the percentage of available contents. Fe-Mn oxide fraction mainly contributed to the removal of copper. As for cadmium, the percentages of acid dissolved fraction, Fe-Mn oxide fraction and organic fraction also decreased. In practical projects, speciation changes would pose certain environmental risk after soil washing, which should be taken into consideration.

Intervention of TLR4 signal pathway cytokines in severe liver injury with obstructive jaundice in rats

Obstructive jaundice is a common surgical disease and a variety of end-stage severe liver injuries still lack effective treatments. Compared to traditional liver transplantation therapy, herbal treatment is noninvasive and has fewer side effects. Research results have shown that a modified major decoction of bupleurum can reduce the toxic reaction of obstructive jaundice, even though the mechanism is unclear. A period of chronic exercise training can significantly reduce TLR4 expression in mononuclear cells and the secretion of inflammatory cell factors. Our study administered a modified major decoction of bupleurum in combination with exercise in rats with obstructive jaundice and the results indicated that applying a major bupleurum decoction in combination with moderately intense aerobic exercise showed a beneficial effect on adjusting the expression of liver inflammatory cytokines, which thus improved immunity and finally reduced the liver injury of rats with obstructive jaundice.

Stepwise regression analysis of the determinants of blood tacrolimus concentrations in Chinese patients with liver transplant

Tacrolimus (FK506) is one of the immunosuppressive drugs used effectively to prevent allograft rejection after liver transplantation. Narrow therapeutic range and individual variance in pharmacokinetics make it difficult to establish a fixed dosage for all patients. Genetic polymorphism in drug metabolizing enzymes and in transporters may influence tacrolimus exposure. A stepwise regression analysis was used to analyze the relationship between blood concentrations of tacrolimus (54 blood samples at the day of 1 week, 2 week and one month after liver transplantation) and genetic & non-genetic factors in 18 Chinese liver transplant patients. The equation of multiple stepwise regression was: Y (tacrolimus' blood concentration) = 34.534 - 0.247 (age) - 0.510 (weight) + 1.688 (dose) + 6.876 (recipient's CYP3A5 genotype) - 3.097 (donor's CYP3A5 genotype), P < 0.01. The factors impacting patient's tacrolimus blood concentrations in a descending order are weight, recipient's CYP3A5 genotype, dose, age, donor's CYP3A5 genotype. Among those, patient's weight and recipient's CYP3A5 genotype could significantly impact the blood concentration of tacrolimus. The influence of recipient's CYP3A5 gene polymorphism is much more obvious than that of donor's. Neither donor's nor recipient's MDR1 genetic polymorphisms were correlated with the blood concentration of tacrolimus.

Frequency of CYP2D6*10 and *14 alleles and their influence on the metabolic activity of CYP2D6 in a healthy Chinese population

To study the frequency of CYP2D6(*)10 and (*)14 alleles in a healthy Chinese population, and the influence of these two alleles on the metabolic activity of CYP2D6. CYP2D6(*)10 and (*)14 genotypes of 295 healthy Chinese subjects were determined using a tetra-primer method and allele-specific amplification. CYP2D6 phenotypes of 131 subjects were determined using dextramethorphan as probe drug. There were 10 subjects with a (*)14 allele, including one homozygous for (*)14. The gene frequency of (*)10 and (*)14 alleles were 55.8 and 1.8%, respectively. The metabolic ratio (MR) of dextramethorphan in 131 subjects was 0.032+/-0.106. The MR of (*)1/(*)1, (*)1/(*)10, (*)10/(*)10, (*)1/(*)14, (*)10/(*)14, and (*)14/(*)14 groups were 0.007+/-0.012, 0.009+/-0.010, 0.042+/-0.029, 0.093, 0.11, and 1.186, respectively. The MR of subjects with (*)14 allele was higher than those of (*)1/(*)1, (*)1/(*)10, or (*)10/(*)10 groups (P<0.001). The CYP2D6(*)10 and (*)14 alleles have substantial impact on the metabolic activity of CYP2D6, and the CYP2D6(*)14 allele may be the cause of the poor metabolizer phenotype in Chinese subjects.

Application of aerobic granular sludge in polishing the UASB effluent

Stable aerobic granules were successfully developed in a sequencing batch reactor (SBR) fed with glucose and sodium acetate as the main carbon sources, and then they were acclimatized to polish the effluent from an up-flow anaerobic sludge blanket (UASB) reactor. It was found that more than 95% chemical oxygen demand (COD) and 85% suspended solids (SS) in the UASB effluent could be removed by an aerobic granular SBR as a post treatment unit. The performance of the SBR was stable over the whole experimental period. At an organic loading rate (OLR) of 4.5 to 5.4 g l(-1) d(-1), the acclimatized aerobic granules had an average diameter of 3.5 to 6.0 mm and a minimal settling velocity of 72 m h(-1). The biomass concentration in the SBR was as high as 8.4 g (dry weight) l(-1). This study showed for the first time that aerobic granular sludge in SBR would be an effective means to polish the effluent from UASB reactor.

The influence of pH on hydrolysis and acidogenesis of kitchen wastes in two-phase anaerobic digestion

Batch and semi-continuous experiments were carried out to determine the effect of pH on hydrolysis and acidogenesis of kitchen wastes in the two-phase anaerobic digestion. The results of the batch experiment showed pH adjustment could improve both hydrolysis and acidogenesis rates of kitchen wastes. Compared with pH at 5, 9 and 11, pH 7 provided an optimum working condition for anaerobic digestion of kitchen wastes. At pH 7, about 86% of the total organic carbon (TOC) and 82% of chemical oxygen demand (COD) were solubilized and the maximum volatile fatty acid (VFA) concentration of 36 g l(-1) was achieved on the fourth day. The total VFA yield was 0.27 g (g total solid (TS))(-1), which almost doubled the yield without pH adjustment (0.15 g (g TS)(-1). The acidified products with lower concentration of lactic acid were more favorable to the subsequent methanogenesis. At pH 7, most of the protein was degraded into ammonia nitrogen (NH4(+)-N), resulting in additional buffer of acidified liquid. According to this, a novel method of pH adjustment applying NH4(+)-N buffer was established. The semi-continuous experiment indicated that adjusting pH to 7 in the acidogenic stage in the two-phase anaerobic digestion process would increase both TS loading rate (16g l(-1) d(-1)) and recovery of biological energy (520 ml methane (CH4) (g TS)(-1)).

[Studies on synthesis and degradation of collagen at transcription level in liver fibrosis of rabbits with schistosomiasis japonica]

OBJECTIVE

To study the synthesis and degradation of collagen at the transcription level during liver fibrosis in rabbits with schistosomiasis japonica.

METHODS

New Zealand rabbits infected with Schistosoma japonicum cercariae were served as animal models of liver fibrosis. The liver specimens were collected through operations at 4, 6, 8, 10, 12, 16, 20, 24 and 28 weeks after infection. Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels of liver tissue were detected by RT-PCR plus dot blotting, and the size of egg granulomas and the degree of liver fibrosis were measured by histopathological examinations.

RESULTS

Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased simultaneously in the early stage after the infection, mostly reaching their peaks at 10 weeks after infection. Compared with normal controls, type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased by 12.0-, 11.0-, 6.6-, 10.0- and 11.0-fold, respectively, coinciding with the changes of egg granulomas. Thereafter, both collagen and collagenase mRNA levels decreased. Types I, III and IV collagen mRNA levels declined to 2-fold to 3-fold compared with normal controls (P < 0.05), while MMP-1 and MMP-9 mRNA levels declined to normal level (P > 0.05) at 28 weeks. This study showed that the synthesis and degradation of collagen remained dynamic balance in the early stage of schistosomiasis, while in the later stage the metabolism of collagen synthesis was higher than that of collagen degradation.

CONCLUSION

It was confirmed at the transcription level that when the metabolism of collagen synthesis was higher than that of collagen degradation in rabbits with schistosomiasis japonica, liver fibrosis might be produced.

[Dynamic changes in collagen type I and collagen type III in rabbits infected with Schistosoma japonicum and the effect of gamma-interferon]

OBJECTIVE

To observe the dynamic changes in collagen type I and collagen type III in rabbits with schistosomiasis japonica and the treatment effect of gamma-interferon on the degradation of collagens in schistosomal hepatic fibrosis.

METHODS

Each rabbit was infected with 80 +/- 1 S. japonicum cercariae. Liver operations were done at different time points after infection and the liver specimens were embedded with paraffin and stained with alpha-SMA, HE and picric acid-Sirius red. The stained slides were observed under polarizing microscope and different collagen areas calculated by computer imagine analysis system. At the 16th week after infection, the infected rabbits received a single dose of praziquantel and gamma-interferon for 8 weeks.

RESULTS

The area percent of collagen type I at the 28th week after infection (40.14 +/- 17.00) increased about seven fold compared with the 8th week group (5.73 +/- 3.40). The area percent of collagen type III at the 28th week after infection (6.80 +/- 5.19) increased about six fold compared with the 8th week group (1.15 +/- 1.34). The alpha-SMA positive cells also increased significantly. After gamma-interferon treatment, the area percent of collagen type I and type III decreased significantly, from 18.51 +/- 7.52 and 4.63 +/- 3.64 (before treatment) to 3.09 +/- 1.54 and 0.40 +/- 0.37 (0 and 4 weeks after treatment) (P < 0.01). However, after the withdrawl of gamma-interferon treatment, the collagen degradation was reversible.

CONCLUSION

Gamma-interferon is effective in the treatment of hepatic fibrosis in rabbits infected with S. japonicum, the effect being reversible.

Isolation and Characterization of EDAG-1, A Novel Gene Related to Regulation in Hematopoietic System

A novel gene, named embryonic develop associated gene 1 ( EDAG -1) and abundantly expressed in human fetal liver tissues, was isolated by screening a human fetal liver cDNA library and the 5' RACE. The full length of EDAG-1 mRNA is 2 166 bp, with an open reading frame of 1 452 bp neucleotides, encoding a 484 amino acid protein. No domain or motif was found similar with other genes by Blast program. Two copies of AUUUA motif in 3' non-translated region show instability of its mRNA. The molecular weight of the protein is 55.3 kD identified by the translation in vitro. EDAG-1 is specifically expressed in hematopoietic tissues, and is quickly down-regulated during the differentiation of K562 cells induced by hemin and EPO. These results show that EDAG-1 is related to the regulation in hematopoietic system and the development of leukemia.

Simultaneous modeling of pharmacokinetics and pharmacodynamics of propafenone in healthy subjects

AIM

To study the simultaneous modeling of pharmacokinetics and pharmacodynamics (PK-PD) of propafenone (Pro) in healthy subjects.

METHODS

Ten healthy Chinese volunteers, 5 extensive metabolizers (EM) and 5 intermediate metabolizers (IM) of CYP2D6, received a single dose (400 mg) of Pro hydrochloride. The blood samples and electrocardiogram (ECG) measurements were taken after administration over 15 h period. The concentrations of Pro in plasma were measured by a reverse-phase HPLC. PR interval was used as an average value of 10 PR interval measurements.

RESULTS

There was a delay between Pro level and percentage of PR interval prolongation. After PK-PD simulating, the relationship between effect concentration (Ce) and the effect met the sigmoid E(max) model. CYP2D6 (EM & IM) played an important role in both pharmacokinetics and pharmacodynamics which produced by Pro. The AUC (microg . h . L-1) of IM group was significantly higher than that of EM group (5126 +/- 1030 vs 2948 +/- 1230, P < 0.05). Whereas Ce50 (microg/L) was also greater in IM group than in EM group (747 +/- 281 vs 359 +/- 123, P < 0.05). On the other hand, gamma of EM group was about one fold larger than that of IM group (P < 0.05).

CONCLUSION

CYP2D6 phenotype of human may influence not only pharmacokinetic of Pro but also its pharmacological effects.

[Identification of gravity-related esterases (grEST1 and grEST2) in carrot callus cells]

A horizontal clinostat which mimics the microgravity in space was used to study its effects on carrot cells. After using boric acid buffer (pH 8.8) as extraction medium, PAGE pattern of esterase isozymes of carrot callus cells displayed 8 bands of which the activities of only 2 were affected by microgravity. They were named grEST1 and grEST2, where grEST stands for gravity-related esterase. The rates of increase in activity of them in carrot cells when cultured on a rotating horizontal clinostat were lower than that cultured in normal gravitational environments, and the difference increased with the culture time. The activities of grEST1 and grEST2 in carrot callus cells subjected to horizontal rotation were found to return to their original levels after being placed under normal gravity (1 x g) for 7 days. We suggest that the effect of simulated microgravity conditions on grEST1 and grEST2 activities in carrot callus cells is through affecting their synthesis. In addition, the activities of grEST1 and grEST2 were not inhibited by eserine, acetylcholine iodide, diisopropyl fluorophosphate and p-chloromercuribenzoate, which indicates that they are acetylesterases.

Influence of simulated microgravity environmental factor on ginseng cell growth and ginseng saponin content

When ginseng (Panax ginseng C.A. Meyer) cells were subjected horizontal rotation on a clinostat, their growth and ginseng saponin content differed from those cultured in normal gravitational environments (control). Both fresh and dry weights of ginseng cells rotating on clinostat were higher than those of the control, and the difference in dry weight was particularly obvious. After 3 weeks of cultivation, saponin content in ginseng was 10% higher under the horizontal rotation treatment on the clinostat than that of the control. When ginseng cells were cultured on Ca2(+)-deprived medium and clinostatted for 3 weeks, their ginseng saponin content was almost twice of that of the control. Besides, in our experiments, the higher the Ca2+ concentration in medium, the lower the ginseng saponin content in the ginseng cells cultured.

Animal experiment and clinical study of effect of gamma-interferon on hepatic fibrosis

AIM

To evaluate the antifibrotic effect of different doses of recombinant human Gamma-Interferon (IFN-gamma) in two rat models of hepatic fibrosis, and to observe its effect on moderate chronic hepatitis B virus fibrosis.

METHODS

Hepatic fibrosis was successfully induced in 150 and 196 rats by subcutaneous injection of carbon tetrachloride (CCl4) and intraperitoneal injection of dimethylnitrosamine (DMN), respectively. Each of the two model groups was divided into: (1) fibrotic model group; (2) colchicine treatment group (0.1 mg/kg/day, gastrogavage for 8 weeks); (3) high-dose IFN-gamma group (15 MU/kg per day, i.m. for 8 weeks); (4) medium-dose IFN-gamma group (5 MU/kg daily, i.m. for 8 weeks); and (5) Y low-dose IFN-gamma group (1.67 MU/kg daily, i.m. for 8 weeks). Another group of 10 rats without any treatment was used as normal controls. At the end of the experiment, semi-quantitative histopathological scores of inflammation and fibrosis, liver alpha smooth muscle actin (alpha-SMA) expression level, liver hydroxyl proline content and serum hyaluronic acid levels were compared. And 47 medium chronic hepatitis B viral fibrosis patients were studied. They were given IFN-gamma treatment, 100 MU/day i.m. for the first three months and 100 MU qod i.m. for the next six months. Semi-quantitative pathological scores of inflammation and fibrosis and serum hepatic fibrosis indices were compared within the 9 months.

RESULTS

In animal experiment, the pathological fibrosis scores and liver hydroxyl proline content were found to be significantly lower in rats treated with different doses of IFN-gamma as compared with rats in fibrotic model group induced by either CCl4 or DMN, in a dose-dependent manner. For CCl4-induced model, pathological fibrosis scores in high, medium and low doses IFN-gamma groups were 5.10 +/- 2.88, 7.70 +/- 3.53 and 8.00 +/- 3.30, respectively, but the score was 14.60 +/- 7.82 in fibrotic model group. Hydroxyl proline contents were 2.83 +/- 1.18, 3.59 +/- 1.22 and 4.80 +/- 1.62, in the three IFN-gamma groups, and 10.01 +/- 3.23 in fibrotic model group. The difference was statistically significant (P<0.01). Similar results were found in DMN-induced model. Pathological fibrosis scores were 6.30 +/- 0.48, 8.10 +/- 2.72 and 8.30 +/- 2.58, in high, medium and low doses IFN-gamma groups, and 12.60 +/- 3.57 in fibrotic model group. Hydroxyl proline contents were 2.72 +/- 0.58, 3.14 +/- 0.71 and 3.62 +/- 1.02, in the three IFN-gamma groups, and 12.79 +/- 1.54 in fibrotic model group. The difference was statistically significant (P<0.01). Serum hepatic fibrosis indices decreased significantly in the 47 patients after IFN-gamma treatment (HA: 433.38 +/- 373.00 vs 281.57 +/- 220.48; LN: 161.22 +/- 41.02 vs 146 +/- 35 +/- 44. 67; PC III: 192.59 +/- 89.95 vs 156.98 +/- 49.22; C-I: 156.30 +/- 44.01 vs 139.14 +/- 34.47) and the differences between the four indices were significant (P <0.05). Thirty-three patients received two liver biopsies, one before and one after IFN-gamma treatment. In thirty of 33 patients IFN-gamma had better effects according to semi-quantitative pathological scores (8.40 +/- 5.83 vs 5.30 +/- 4.05, P<0.05).

CONCLUSION

All the three doses of IFN-gamma are effective in treating rat liver fibrosis induced by either CCl4 or DMN, the higher the dose, the better the effect. And IFN-gamma is effective for patients with moderate chronic hepatitis B viral fibrosis.

[Allele specific amplification for CYP2D6 gene related to intermediate metabolizer in Chinese subjects]

AIM

To establish an allele specific PCR amplification (ASA-PCR) for determination of the genotype of CYP2D6* 10B polymorphism in Chinese subjects.

METHODS

CYP2D6* 10B alleles of 65 healthy Chinese subjects were analyzed by a two-step PCR assay and the correlation of genotype and phenotype was studied.

RESULTS

There were 20 CYP2D6* 10B heterozygous genotypes subjects (wt/m) in 35 very extensive metabolizers (VEMs), which consisted the major part of VEM subjects (57%). Meanwhile, 20 subjects consisting 69% of 29 intermediate metabolizers were CYP2D6* 10B homozygous mutant genotypes (m/m). The poor metabolizer was also m/m. The metabolic ratio of CYP2D6* 10B m/m subjects were larger than wt/m and wild type, the values were -1.49 +/- 0.54, -2.20 +/- 0.49 and -2.47 +/- 0.61 (P < 0.01).

CONCLUSION

PCR-ASA was shown to be a rapid and specific method. It can be used to study the genetic polymorphism, especially CYP2D6 intermediate metabolism.

[Peroxidase isoenzymes analysis on some plants under simulated microgravity]

The detection technology of peroxidase isoenzyme pattern were adopted in the study of the effect of simulated microgravity on some plants. Biochemical analysis indicated that the microgravity samples displayed an increased activity of peroxidase.

[Derivative gas chromatographic analysis of fructooligosaccharide in fermented sucrose]

As a new sweetener, fructooligosaccharide is paid more and more attention for its health improvement property. It includes trisaccharide, tetrasaccharide and pentasaccharide, and can be produced from sucrose by the fermentation of microorganism. In order to analyze the content of fructooligosaccharide in fermented sugar by gas chromatography, fructooligosaccharide was transformed into trimethylsilyl derivatives. Based on the modified gas chromatograph SP2308, and under the chosen chromatographic conditions with 0.53 mm capillary column of OV-101, the contents of fructose, glucose, sucrose and fructooligosaccharide were determined by programmed temperature chromatography. The recovery of fructooligosaccharide was satisfactory.

Fluoxetine impairs the CYP2D6-mediated metabolism of propafenone enantiomers in healthy Chinese volunteers

OBJECTIVE

To determine the effect of 20 mg/day fluoxetine on the pharmacokinetics of propafenone enantiomers and CYP2D6 activity by phenotyping with dextromethorphan.

METHODS

Nine healthy Chinese volunteers (seven men and two women) were included in a two-phase study. Dextromethorphan (20 mg) was given before and after subjects took 20 mg/day fluoxetine for 10 days, and the dextromethorphan metabolic ratio was calculated to determine CYP2D6 phenotype. Pharmacokinetic studies of propafenone enantiomers after a single oral 400 mg dose before and after pretreatment with 20 mg/day fluoxetine for 10 days were also conducted in these subjects. Reversed-phase HPLC with precolumn derivatization was used to determine enantiomeric concentrations of propafenone in plasma.

RESULTS

Mean CYP2D6 dextromethorphan metabolic ratios before and after fluoxetine therapy were 0.028 +/- 0.031 and 0.080 +/- 0.058, respectively (P = .001), indicating that a strong inhibition of CYP2D6 by fluoxetine activity was observed in Chinese subjects. Propafenone metabolism was also impaired significantly after fluoxetine treatment. The elimination half-life, peak concentration, and area under the curve from 0 hours to infinity of two enantiomers after fluoxetine therapy were significantly increased compared with those at baseline (P < .01), whereas oral clearance decreased from 75.01 +/- 17.69 L/h to 49.36 +/- 8.62 L/h for S-propafenone (P = .005) and from 107.62 +/- 33.82 L/h to 70.60 +/- 12.42 L/h for R-propafenone (P = .027). In addition, fluoxetine increased the peak concentration of S-propafenone by 39% and that of R-propafenone by 71% (P < .05). A significant increase of the time to reach peak concentration was observed only in the R-enantiomer and not in the S-enantiomer of propafenone after fluoxetine therapy. There were no differences in the percentage changes of PR and QRS intervals before or after fluoxetine pretreatment at the time observed (P > .05).

CONCLUSION

We conclude that fluoxetine may cause significant inhibition of the CYP2D6 activity as determined by dextromethorphan phenotyping. This inhibition impairs the metabolism of propafenone enantiomers in Chinese subjects. Caution must be exercised when fluoxetine and propafenone are coadministered to avoid potential toxicity.

[The reactions in ginseng cells induced by elicitor derived from digesting ginseng cell walls by cellulase]

After treatment of the elicitor derived from digesting ginseng cell walls by cellulase, the starch grains were degraded, and a large number of spherosomes were produced in Ginseng cells. In the mean time, the activity of amylase in the cells was increased and the activities of esterases in the cells were reduced; in addition, the content of soluble sugar and the content of lipoid were increased. These indicate that the emergency reactions and the adjustment of metabolism of lipoid were taken placed in the cells elicited. Besides, after the treatment with certain concentrations of elicitor, the content of ginseng saponin and the activity of phenylalanine ammonia lyase (PAL) were increased in ginseng cells. On the contrary, the activities of peroxidase (POD) and polyphenoloxidase (PPO) were reduced.

CYP2D6 phenotype determines pharmacokinetic variability of propafenone enantiomers in 16 HAN Chinese subjects

AIM

To determine the role of the CYP2D6 phenotype in the metabolism of propafenone (Pro) enantiomers in 16 HAN Chinese subjects.

METHODS

Seven very extensive metabolizers (VEM) and nine intermediate metabolizers (IM) were enrolled from a Chinese population whose phenotype had been previously assessed with a dextromethorphan metabolic phenotyping. The blood samples (0-15 h) were taken after oral administration of a single dose (400 mg) of rac-Pro hydrochloride. Enantiomeric concentrations of propafenone in plasma were measured by a reverse-phase HPLC with precolumn derivatization.

RESULTS

S-Pro was less metabolized and had higher plasma concentrations than R-Pro in both CYP2D6 phenotypes. Besides, the T1/2 of R-Pro was longer than that of S-Pro in IM, but not in VEM. However, there were significant differences in the metabolism of Pro enantiomers between VEM and IM. The Cmax and AUC of both isomers in the IM group were higher than those in the VEM group (P < 0.01). The Cl of Pro enantiomers in IM group was only about half of that in VEM group [(67 +/- 17) vs (133 +/- 28) L.h-1 for S-Pro, (90 +/- 24) vs (200 +/- 87) L.h-1 for R-Pro, P < 0.01]. The S/R ratios of T1/2, Tmax, Cmax, Cl, and AUC were not significantly different (P > 0.05).

CONCLUSION

CYP2D6 phenotype determines the pharmacokinetic variability of propafenone enantiomers and existence of IM may be relevant to diminished capacity of CYP2D6 enzyme in Chinese subjects.

The influence of CYP2D6 activity on the kinetics of propafenone enantiomers in Chinese subjects

AIMS

To determine role of CYP2D6 activity in the pharmacokinetics of propafenone (PPF) enantiomers in native Chinese subjects.

METHODS

Sixteen extensive metabolizers (EMs) and one poor metabolizer (PM), whose phenotype had been previously assessed with dextromethorphan metabolic phenotyping, were enrolled. Blood samples (0 approximately 15 h) were taken after oral administration of a single dose (400 mg) of racemic-propafenone hydrochloride. A reverse-phase h.p.l.c. method with pre-column derivatization was employed to quantitate enantiomeric concentrations of propafenone in plasma.

RESULTS

For the EM subjects, S-PPF was less rapidly metabolized and had higher peak plasma concentrations than R-PPF (413+/-143 vs 291+/-109 ng ml-1, P<0.001). The AUC was markedly higher for S-PPF than for R-PPF (2214+/-776 vs 1639+/-630 microg h l-1, P<0.001), whereas the clearance of S-PPF was significantly lower than that of R-PPF (96.0+/-39.0 vs 138+/-78 l h-1, P<0.01). There were no differences in t1/2, and Cmax between the two isomers (P >0.05). In the one PM subject, not only did S-PPF appear to undergo less rapid metabolism than R-PPF, but the subject also showed 2 approximately 3 fold differences in Cmax, CL and AUC compared with EMs. The correlation coefficients (rs ) between dextromethorphan metabolic ratio (lg MR) and pharmacokinetic parameters (Cmax, CL and AUC) were 0.63, -0.87, 0.87 for S-PPF and 0. 57, -0.73, 0.86 for R-PPF, respectively.

CONCLUSIONS

Our results suggest that CYP2D6 activity contributes to the pharmacokinetic variability of propafenone enantiomers in Chinese subjects.

[Characters of two gravity-related esterases in carrot callus cells]

On the basis of identification of two gravity-related esterases (grEST1 and grEST2) in carrot callus cells (Cai et al. 1998), we continued the study of the characteristics of these two esterases. They have the very special characteristic of SDS resistance. Their activities could be inhibited partially by deoxycholate. beta-Phenylpropionic acid, AgNO3 and CuSO4 had no inhibitory effect on their activities. The activities of grEST1 and grEST2 could be decreased by ascorbic acid and cysteine, and the influence by cysteine was particularly obvious. The molecular weights of grEST1 and grEST2 were shown to be near the ranges of 49-66 kD and 43-59 kD respectively by non-denaturing electrophoresis containing deoxycholate, Triton X-100 and SDS respectively, and the isoelectric points were approximately pH 5.4 and 4.9 respectively. Besides, grEST1 and grEST2 were found in the fraction precipitating at value between 30% and 40% saturation with (NH4)2SO4.

[Analysis of population pharmacokinetics with NONMEM in clinical patients treated with amikacin by intravenous infusion]

Clinical data (n = 275) collected from 52 patients with respiratory tract infection receiving amikacin (AMK) by intravenous infusion were analysed with NONMEM, a computer program designed for estimating population pharmacokinetic parameters. Concentrations of AMK in serum were determined by fluorescence polarization immunoassay (FPIA). A two compartment open model was used for analysing AMK population pharmacokinetics. The influence of body weight (BW), creatinine clearance (CC), administration history (HIS) and state of pathology (chronic obstructional pulmonary disease, COPD) on pharmacokinetics was investigated. The pharmacokinetic parameters of AMK were shown to be influenced by creatinine clearance (CC) and COPD.

[Distinguishing CYP2D6 homozygous and heterozygous extensive metabolizers by dextromethorphan phenotyping]

A more sensitive procedure was developed to phenotype cytochrome P450 2D6 metabolism by a less toxic probe drug--dextromethorphan. The sensitivity of the determination of dextromethorphan in urine samples was up to 1 ng.ml-1. This method was employed to phenotype three groups of subjects. The results showed that there was a difference between extensive metabolizers which were genotyped as homozygotes and heterozygotes. Although the difference was not as big as the difference with poor metabolizers which were genotyped as homozygous mutants. It suggests that "gene copy" is a true factor in the expression of CYP2D6 genes.

High performance liquid chromatographic determination of dextromethorphan and its metabolite in human urine

A reverse-phase high-performance liquid chromatographic method was established for the determination of dextromethorphan (DM) and its metabolite dextrophan (DX) in human urine. The sample was purified by an acid-base extraction followed by HPLC analysis on a phenyl column. The eluate was monitored by fluorescence at 280 nm (excitation) and 310 nm (emission). The limit of detection of DM was 0.023 mg.L-1. The within-day and between-day RSD% of DM and DX were all lower than 5%. The average recovery was 104.78%.

Dextromethorphan metabolic phenotyping in a Chinese population

AIM

To establish a phenotyping of dextromethorphan (DM) oxidation polymorphism in a native Chinese population.

METHODS

The urine concentrations of DM and its metabolite dextrophan (DX) were assayed by HPLC and metabolic ratios (MR) were calculated in 120 unrelated native Chinese subjects after ingestion of DM 20 mg.

RESULTS

The incidence of poor metabolizers was 0.8% (one in 120 subjects). There were distinct dimodal distributions which divided extensive metabolizers into 43 intermediate metabolizers and 76 very extensive metabolizers. The 0-8 h urinary recoveries of DM and DX were 0.4% +/- s 0.5% and 26% +/- s 13%, respectively. There was no difference in 0-8 h urinary recoveries between male and female subjects.

CONCLUSION

DM metabolic phenotyping provides a new information for debrisoquine 4-hydroxylation (CYP2D6) polymorphism in native Chinese.

Displacement of statoliths in Chara rhizoids during horizontal rotation on clinostats

The basipetal movement of statoliths in Chara rhizoids, similar to that during parabolic flights of TEXUS rockets occurs also during rotation on clinostats. Within 15 min on fast-rotating clinostat, the distance between the center of the statolith complex and the cell vertex increases for 60% of that in positively gravitropic downward growing rhizoids. Cytochalasin D experiments confirm that the movement of statoliths is actin-dependent and the actin filaments exert basipetal forces on statoliths in gravity field. The clinostat and/or cytochalasin experiments confirm the suggestion that on earth the position of statoliths depends on the balance of the gravitational force and the counteracting force mediated by actin filaments. The statolith center keeps a stable position during about 30 min on a fast-rotating clinostat, i.e. it is then in a new dynamically stable state. This new state is achieved 15 min after the basipetal acting filament-mediated force has been disturbed by clinostatting. Further experiments on the fast-rotating clinostat show that this new position brings about a reorganization of actin filaments which makes the process of acropetal transport of statoliths possible. The amplitude of particle oscillatory movement decreases as the rotational speed of the clinostat increases. This explains the differences of the results obtained from the experiments on fast-rotating and slow-rotating clinostats. It should be kept in mind that rhizoids are unicellular. The fast-rotating clinostat is suitable for simulation of conditions without gravity when a rhizoid is on the axis of rotation. The interaction of statoliths and actin filaments at zero gravity can be studied by means of such a clinostat.

A simplified high-performance liquid chromatographic method for direct determination of warfarin enantiomers and their protein binding in stroke patients

A simplified method for direct determination of warfarin enantiomers by high-pressure liquid chromatography with fluorescence detection has been developed. This method involves solid phase extraction of warfarin in plasma, precolumn derivatization to form diastereoisomeric esters, and post-column reaction to discriminate each enantiomer separately. Ultrafiltration was employed in the separation of unbound warfarin enantiomers. Twelve plasma samples from six stroke patients taking warfarin regularly were analyzed. The average concentration of total warfarin was 0.47 +/- 0.17 mg/L for the S-isomer and 0.69 +/- 0.18 mg/L for the R-isomer. The average protein binding was 99.67 +/- 0.33% for S-warfarin and 99.44 +/- 0.33% for R-warfarin. This methodology provides a quick and reliable technique for determining enantiomeric protein binding of warfarin in clinical settings.

Influence of serum separator tubes on total and free phenytoin concentrations and dosages

The influence of serum separator tubes (SSTs) on total and free phenytoin concentrations and phenytoin dosages was evaluated in patients treated with phenytoin. Thirty blood samples were obtained from 18 patients. Equal volumes of blood were placed into SSTs and plain tubes. Samples were centrifuged, and serum analyzed for total and free phenytoin by fluorescence polarization immunoassay (FPIA) at 2, 24, and 48 h. Total phenytoin concentrations collected in SSTs were significantly lower than those collected in plain tubes at 2 (12.3 vs 12.8 mg/L, p < 0.01), 24 (11.4 vs 12.9 mg/L, p < 0.01), and 48 h (10.9 vs 12.9 mg/L, p < 0.01). These differences resulted in significantly higher calculated maximum rates of metabolism (Vmax) and daily phenytoin dosages (R0) for SSTs at 24 (Vmax: 10.4 vs 10.1 mg/kg/day; R0: 8.2 vs 8.0 mg/kg/day, p < 0.01) and 48 h (Vmax: 10.8 vs 10.3 mg/kg/day; R0: 8.5 vs 8.1 mg/kg/day, p < 0.01). Free phenytoin concentrations from SSTs were significantly lower at 48 h (1.56 vs 1.61 mg/L, p < 0.05). However, there were no significant differences in calculated dosages. Observed statistical differences in total phenytoin concentrations can be clinically important for making dosage adjustments, especially in patients undergoing nonlinear elimination. Thus, SSTs should not be used to collect blood for total serum phenytoin determination.

Preliminary experience in HDR brachytherapy for 72 nasopharyngeal carcinoma patients

From April 1989 to July 1991, 72 patients with residual or recurrent nasopharyngeal carcinoma (NPC) were treated by MSH Ir-192 brachytherapy or combined external radiation therapy. All were proven histologically. 39 patients with residual disease and 6 with recurrent lesion at the primary site were identified after one or more courses of radical external radiation. Eleven patients had received brachytherapy for boost therapy after one or more courses of external radiation. Sixteen were treated with a planned protocol of external irradiation combined with intracavitary brachytherapy. The overall local control rate was 93.3%; the local control rate for residual and recurrent disease was 100% and 50%, respectively. Soft palate perforation was observed in 3 patients. Brachytherapy is believed to be a useful treatment for residual or recurrent NPC following radical external radiation.

Free phenytoin monitoring in serum and saliva of epileptic patients in China

Twenty-three serum samples and 13 saliva samples from 14 Chinese epileptic patients treated with phenytoin (DPH) were obtained to study the correlations between total, free serum, and saliva DPH concentrations. The binding of DPH to serum protein was assessed by equilibrium dialysis, and total and free DPH concentrations were analyzed with a domestic fluorescence polarization immunoassay reagent by the TDx system. A strong correlation existed between the total and free concentrations (r = 0.90, n = 20, p < 0.001). The mean value for the DPH free fraction was 11.13 +/- 3.65%. The mean value for the saliva fraction was 9.40 +/- 2.60%. This is the first attempt to monitor free DPH concentrations in serum in Chinese patients.

Studies on ultrasonographic diagnosis of schistosomiasis japonica in China--a review of selected Chinese studies

Diagnostic ultrasound has been used in China since the early 1960's in the investigation of Schistosoma japonicum infection. This paper presents an overview of selected papers from the Chinese literature on the use of ultrasound in studies of schistosomiasis japonica, and briefly reports the results of studies not yet published elsewhere. The method is compared with other diagnostic procedures, and the benefits and limitations of using ultrasound are discussed.

A Bayesian graphic method for predicting individual phenytoin dosage schedule

A simple and practical graphic method based on Bayesian feedback theory for predicting individual phenytoin dosage was evaluated. Compared with the mathematical calculation, the graphic method only needs one pair of steady-state phenytoin concentration-dose data to predict individual phenytoin dosage. The observed drug levels were compared with predicted ones in 12 epileptic out-patients with a correlation coefficient of 0.94. The mean error between the observed and predicted phenytoin levels was 0.62 mg.L-1. The mean kinetic parameters Vm and Km obtained from the graph were 7.01 +/- SD 0.88 mg.kg-1.d-1 and 4.93 +/- 0.91 mg.L-1, respectively.

Photodynamic therapy in the treatment of malignant tumours: an analysis of 540 cases

Malignant tumours (540 cases), including tumours of the lung, oesophagus, cardia, stomach, rectum, bladder, other urinary genital organs, face and mouth, eyes, ear, nose and throat (ENT), head and neck, breast and skin, were treated using photodynamic therapy (PDT) between 1982 and 1985 in Beijing. All of the cases were identified pathologically and the patients received haematoporphyrin derivative (HPD) (5 mg kg-1) intravenously 48-72 h prior to PDT. An argon-pumped dye laser emitting at 630 nm was used for the treatment. The results were as follows: complete response (CR) was obtained in 227 cases (42.1%), partial response (PR) was obtained in 114 cases (21.1%), mild response (MR) was obtained in 120 cases (22.2%) and 79 cases (14.6%) showed no response (NR). The effectiveness of PDT in the different organs was compared. HPD fluorescence was examined in 409 cases of malignant tumours: 344 lesions (84.1%) revealed red fluorescence (positive reaction), 32 gave an equivocal response and 33 gave a negative reaction. Positive fluorescence was seen in all types of malignant tumour in our study. Indications and limitations of PDT for the different organs are discussed and compared.

[Result and indication of photodynamic therapy in the treatment of malignant tumors--analysis of 165 patients]

Evaluation of the effect of photodynamic therapy (PDT) on cancers is presented. Indication of PDT in the treatment of 165 cancer patients, including 68 superficial, 33 head and neck, 57 bladder and 7 other cancers treated from Sept. 1981 through 1985 is reported. The overall effective rate was 83.6%. The immediate response rates were as follows: complete response 58.2%, marked response 13.3%, mild response 12.1% and no response 16.4%. The longest cancer-free survival was over six years. Based on this material the indications of PDT on cancer are suggested as: 1. superficial and early cancers; 2. orifice obstruction in the alimentary or respiratory tract; 3. local residual or recurrent cancer after surgery or radiotherapy; 4. bladder cancer. The disadvantages of PDT are discussed.

[Influence of total parenteral nutrition on amikacin pharmacokinetics]

Six patients under total parenteral nutrition (TPN) and eight control patients received 200 mg of amikacin by iv infusion in 0.5 h. Amikacin concentrations of serum and urine were determined by fluorescence polarization immunoassay. At 6 h after the beginning of administration, the amikacin level in serum of TPN group (2.3 +/- 0.8 micrograms/ml) was significantly higher than control (1.3 +/- 0.8 microgram/ml). There was no significant difference between the 24-h urine output of 2 groups. Pharmacokinetic calculations were based on a two-compartment open-system model. The T1/2 beta and apparent volumes of distribution (Vc, Vdss, V2) of TPN group were significantly greater than those of control group. The body clearance of amikacin in TPN group was slower than control. It is suggested that serum amikacin concentrations should be monitored in clinical TPN patients to prevent toxic reactions.

Management of local residual primary lesion of nasopharyngeal carcinoma (NPC): are higher doses beneficial?

One hundred and eighty-two nasopharyngeal carcinoma (NPC) patients, treated from March 1958 through 1978, received 70 Gy or more and were left with gross residual lesion in the nasopharynx, were retrospectively analyzed. Ninety-two patients were given a boost by reduced portals to a total of 90-120 Gy (boost group) whereas for the other non-randomized 90 patients, the treatment was stopped at 70 Gy (observation group). The local recurrence, distant metastasis and 5-year survival rates of the two groups are: 35% (32/92) vs. 58% (52/90), 20% (18/92) vs. 43% (39/90), and 54% (50/92) vs. 21% (19/90), respectively. The benefit of boost is more apparent in patients with T1-2 than T3-4 lesions (p less than 0.001), at increased risk of radiation encephalo-myelitis from 5.5% to 17%. The authors believe that boost be given to patients with early Stage T or small residual lesion at the primary site of NPC.

Chinese herb "destagnation" series I: Combination of radiation with destagnation in the treatment of nasopharyngeal carcinoma (NPC): a prospective randomized trial on 188 cases

The results of a prospective randomized trial on 188 patients with NPC is reported to evaluate the validity of Chinese herbal medicine-Destagnation combined with radiotherapy. Ninety patients were allotted to the Destagnation group (radiation plus Destagnation) and 98, to the control group (radiation only). The 5-year success rate (number surviving minus number recurred but salvaged by re-treatment) of the Destagnation group is 53% (48/90) in comparison to 37% (36/98) of the control group (p less than 0.05). Minor complications of Destagnation included occasional anorexia and frequency of bowel movement. The reduced rate of local recurrence at the primary site in the Destagnation group (14%-13/90) as compared to that of the control group (29%-28/98) (p less than 0.05) suggests that Destagnation may be a radiosensitizer. The similar metastatic rates in both groups; 21% (19/90) in the Destagnation group and 21% (21/98) in the control group may refute the belief that Destagnation enhances hematogenous spread.

Long-term survival of 1035 cases of nasopharyngeal carcinoma

Long-term results of 1035 previously untreated patients with nasopharyngeal carcinoma seen at Cancer Hospital, Chinese Academy of Medical Sciences, between March 14, 1958 and March 15, 1968 are presented. Of the 1035 patients, 715 were treated with radiation therapy; 281 patients did not receive radiation therapy; and 39 patients whose records were lost. The patients were further subdivided according to the dose of radiation therapy (greater than 4000 rad versus less than 4000 rad), the presence or absence of pathologic confirmation of diagnosis, whether or not follow-up was complete, and whether or not distant metastases developed during treatment. All patients are included in the analysis. The 5-year and 10-year absolute survival rates for the entire group of 1035 patients are 19.6% and 14.5%, respectively. The 5-year and 10-year relative survival rates for the 715 patients who received radiation therapy are 28.4% and 21.0%, respectively. The 5-year and 10-year relative survival rates of the 464 with a pathologically confirmed diagnosis, who were without evidence of distant metastases and who received at least 4000 rad were 34.7% and 25.4%, respectively. Details regarding our statistical methods as well as an exact breakdown of the patient population are presented.

[Radiotherapy of nasopharyngeal carcinoma--analysis of 1379 patients]

This paper presents 1379 patients with nasopharyngeal carcinoma treated in our hospital from March 1958 to December 1978. The stage I and II lesions comprised 22% and stage III and IV lesions, 78%. 220 KV X-ray was used before 1960 and 60Co was predominant from 1961 through 1978. The overall 5 year survival rate was 41.4% (571/1379). Young adults and female patients gave better results. The 5 year survival rate was, according to pathological type, 45.1% for poorly differentiated squamous cell carcinoma and 13% for adenocarcinoma; according to clinical stage, 85.7% for stage I lesion, 59.5% for stage II, 45.8% and 29.2% for stages III and IV; according to period of treatment, 31.3% in the sixties and 48.6% in the seventies; according to tumor dose at the primary focus, 48.2% for 40-49 Gy, 55.6% for 60-69 Gy and 67.3% for 90 Gy or more; according to with or without prophylactic radiation in the neck region, 53.8% for the former and 23% for the latter. It implies that prophylactic radiation of the neck is necessary regardless of the presence of cervical lymph node metastasis or not. For those who had residual tumor at 70 Gy, the total dose may be boosted to more than 90 Gy with the cone down technic or the dose, at which the primary lesion disappears grossly, is added with 20 Gy. The common complications are radiation myelitis, trismus and otitis media. As in certain patients, the lesion would still recur 5 years after radiotherapy, the authors believe that the nasopharyngeal cancer patients should be followed for ten years at least.

Analysis of 1379 patients with nasopharyngeal carcinoma treated by radiation

One thousand three hundred seventy-nine nasopharyngeal carcinoma (NPC) patients were treated from March 1958 to December 1978. Twenty-two percent had stage I or II and 78% Stage III or IV had lesions. Two hundred twenty-Kv radiographs were used before 1960; and telecobalt was used from 1961 to 1978. Factors influencing the 5-year survival rate favorably are youth of patient, being female, pathologic condition (poorly differentiated carcinoma, 45.1% versus adenocarcinoma, 13%), stage (Stage I, 86%, Stage II, 59.5%; Stage III, 45.8%; Stage IV, 29.2%), decade admitted for treatment in the past (31% in the 1950s, 48.6% in the 1970s), total dose delivered to the nasopharynx (40 to 49 Gy, 46%; 70 to 79 Gy, 54.1%; 90 Gy or more, 64%) and prophylactic radiation to the neck regions (with prophylactic irradiation, 53.8%, without prophylactic irradiation, 23%). This implies that prophylactic radiation of the neck is crucial even without positive clinical metastasis. For those who have a residual tumor in the primary site when 70 Gy has been delivered, the total dose may be boosted to more than 90 Gy with the cone-down technique or on basis of adding 20 Gy to the dose at which the primary lesion disappeared grossly. The common postirradiation complications are: radiation myelitis, trismus, and otitis media. Because disease recurred in some patients after the fifth year, NPC patients should be followed for at least 10 years.

Serologic diagnosis of nasopharyngeal carcinoma. A double-blind study of four EB virus antibodies with evaluation by sequential discrimination

It is generally known that a close relationship exists between Epstein-Barr Virus (EBV) and nasopharyngeal carcinoma (NPC). Recently, patients with early lesions of NPC have been detected in the general population by use of serologic mass survey. Using the double-blind method, we have studied the diagnostic value of the four EBV antibody titers, VCA-IgA, VCA-IgG, EA-IgA and EA-IgG, in four groups of subjects, each consisting of 50 persons: patients with nasopharyngeal carcinoma (NPC group), patients with cancers other than NPC in the head and neck regions (HNC group), patients with cancers outside of head and neck regions (OC group) and normal individuals (NS group). The results of these four antibodies were evaluated both singularly and together by multivariate sequential discrimination. Taking 1:10 as the criterion of being positive, in the NPC group, the positive rate of VCA-IgA is 88%, the VCA-IgG rate is 100%, the EA-IgA rate is 48% and the EA-IgG rate is 74%. In the non-NPC group, the positive rates of VCA-IgA are as high as 86%-92%, but those of the other antibodies are as low as 0-42%. The positive rates and the geometric mean titers of these four antibodies were all elevated as compared with those in the three non-NPC groups. These differences are statistically significant. VCA-IgG is unimportant in the diagnosis of NPC because of its low specificity. By treating the antibody titers of VCA-IgA, VCA-IgG, EA-IgA and EA-IgG with sequential discrimination, the correlation rate between the serology and pathology of NPC is 88% and the false positive rate is 7.3%.

Influence of biopsy on the prognosis of nasopharyngeal carcinoma--a critical study of biopsy from the nasopharynx and cervical lymph node of 649 patients

Most of the nasopharyngeal carcinomas (NPC) are histopathologically either poorly differentiated or undifferentiated. After radiotherapy, hematogenous spread is the chief cause of failure for these patients. Biopsies taken from the nasopharynx or the enlarged neck nodes should be performed to establish diagnosis before radiotherapy. The present study was done to ascertain whether the biopsy procedure would affect the final outcome of this malignancy, and to establish certain criteria for clinicians as they endeavor to correctly diagnose and prepare the patients for treatment. Six hundred and forty-nine of 702 NPC patients treated in our hospital from March 1958 through 1972 were analyzed for this purpose and the results are as follows: For patients with fixed and partially fixed neck nodes, the interval between the first biopsy and radiotherapy, the number of times or frequency of biopsy either taken from the nasopharynx or the lymph node and the type of biopsy done on the lymph node did not influence the prognosis. For patients with or without only movable neck nodes, the interval between the first biopsy from the nasopharynx and radiotherapy influenced the final outcome. Patients who received radiotherapy within 14 days after biopsy had a five year survival of 61% (42/69), which is better than that of the patients who started their treatment beyond the 15th day (47.5%-58/122). This is statistically significant (p less than 0.05). The number of times or frequency of biopsy taken from the nasopharynx before radiotherapy did not influence the result of treatment. The interval, therefore, and not the frequency, is important in the biopsy from the nasopharynx. For patients with movable lymph nodes, partial excision of the node gave a poorer five year survival (22%-2/9) than that of patients on whom complete excision was done (50%-9/18). Therefore, complete excision of the node is advised for patients with movable neck node metastasis.