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To investigate the process of ion permeation in an ion channel systematically, we performed molecular dynamics (MD) simulations on a gramicidin A (GA)-phospholipid model system with an ion in the channel pore region. Each of the three types of ions (Ca2+, Na+ Cl-) was placed at five different positions along the channel axis by replacing a water molecule. MD simulations were performed on each system at constant pressure and constant temperature. The MD trajectories showed that the Ca2+ and Na+ ions could stably fluctuate in the pore region, but the Cl- ion was pushed out because of the unfavorable interaction with the channel. This result is consistent with experimental data. It was also found that the conformation of the GA channel underwent a significant change due to the presence of the ion, and the two ends of the GA monomer were more flexible than its middle region. In particular, the dramatic change of local pore radius near the ion indicated this kind of deformation. The strong interaction between the ion and carbonyl oxygen atoms of GA was the major contributor to this change. Furthermore, it was found that the ethanolamine group of the GA molecule was the most flexible group in the GA channel and often observed to block the entrance of GA. These results imply that the deformation of channel structure plays a very important factor in ion permeation, and the ethanolamine group may play a key role in regulating ion entry into the pore. In conclusion, our results indicate that the ion has a dominant influence on the structure of the GA channel and that the flexibility of the ion channel is a crucial factor in the ion permeation process.

As a continuing study of chemical characterization of crude drug processing, we have been analyzing the chemical constituents in licorice roots before and after processing. At first, we analyzed chemical constituents in licorice roots of various origins. Next, we have developed the HPLC analytical method, by which saponins and flavonoids, major constituents in various licorice roots, were determined simultaneously in a quantitative manner. In this paper, by means of the HPLC analytical method, chemical constituents in licorice roots, processed and unprocessed, were determined. It was found that nonglycosidic flavonoid constituents were mostly lost while root bark removing, whereas, in roasted licorice roots, sugar chains in the saponin and glycosidic flavonoid constituents were hydrolyzed stepwise during roasting through hydrothermolysis.

Excessive production of nitric oxide (NO) may have cytotoxic effects through the formation of peroxynitrite with superoxide. The extract of Ginkgo biloba leaves (EGb) has been demonstrated to be a potent scavenger of free radicals. Although EGb has been shown recently to inhibit NO production in macrophages, its effect on NO production in endothelial cells is largely unknown. The objective of this study was to elucidate the mechanism by which EGb affects NO production in a human endothelial cell line (ECV304). After cells were incubated with EGb (10-100 microg/mL) for 2 or 4 hr, the amounts of NO metabolites released by the cells were quantitated, and cellular NOS activities were determined following the conversion of [3H]arginine to [3H]citrulline. NOS protein expression was determined by western immunoblotting analysis. mRNA levels were examined by reverse transcription-polymerase chain reaction (RT-PCR) analysis. EGb (50 microg/mL) caused a 30% reduction of NO metabolites released by endothelial cells. Following EGb treatment, cellular inducible NO synthase (iNOS) activity was reduced by 28% with a concomitant reduction in the levels of iNOS protein mass and mRNA. There was no change in the activity or protein mass of constitutive NO synthase in these cells. EGb inhibited NO production by attenuating the level of iNOS mRNA in ECV304 cells. Selective inhibition of iNOS by EGb may be therapeutically relevant in modulating NO production in endothelial cells.

A method for constructing the suitable initial configuration of the membrane-protein system for molecular dynamics (MD) simulations is presented. This method could provide some hydrated initial configurations and help us to determine the best surface area of the system by contracting the surface area and comparing the optimized lowest energy of the system by energy minimization. The gramicidin A (GA) channel in;the fully hydrated dimyristoylphosphatidylcholine (DMPC) bilayer was used as our model. Three configurations with different surface areas were selected and applied for one 400 ps and two 300 ps MD simulations at constant pressure and temperature. All simulations were fairly stable without any constraints. Through analysis of the MD trajectories we found that the system with the best surface area was more stable than the other two systems, whose sizes were changed in the simulations. Further analysis of the bilayer normal length and the order parameters of the lipid alkyl tails indicates that the system with the best surface area shows some characteristics of the L(alpha) phase, while both the smaller and the larger size systems have distinct deviations from the L(alpha) phase that we expect. This illustrates that the correct surface area and the suitable initial configuration have an important influence on the phase of the membrane in the MD simulation. In addition, by comparing the root mean square differences of GA relative to the initial structure and interaction energy between different components of the system for all three systems, we find that the state of the DMPC bilayer has exerted a significant influence on the structure of GA. All these results demonstrate the validity of our method for constructing the initial configuration of the membrane-protein system for MD simulations.

During the course of our studies on the chemical constituents of botanically identified Chinese licorice roots of various origins, we have identified 15 kinds of saponins and 49 kinds of flavonoids (including flavonoid glycosides). With these chemical constituents at hand, we have carried out the chemical evaluation studies of licorice roots available in Japan by means of high performance liquid chromatography (HPLC). In the HPLC analysis using an ODS reversed-phase column, a combination of 1% aqueous acetic acid and acetonitrile was used as the mobile phase in a gradient solvent system, and the eluate was monitored with UV absorption at 254 nm (for saponins with a diene or a conjugated carbonyl moiety, liquiritin, and liquiritin apioside) or at 350 nm (for other flavonoid constituents). By our analytical method described here, quantitative analyses of saponin and flavonoid constituents were effected simultaneously. We have found an interesting piece of information concerning the origin of parent plants and their characteristic constituents such as saponins and flavonoids.

Aim: To study the protective effects of Ginkgo biloba extract (GbE) against endothelial cell damage induced by lysophosphatidylcholine (LPC)., Methods: The vasorelaxation response to acetylcholine (ACh) were investigated in the isolated rabbit thoracic aorta. Lipid peroxidation products were determined by measuring thiobarbituric acid reactive substance., Results: GbE attenuated the inhibition of vasorelaxation response to ACh and prevented the LPC-induced increase of malondialdehyde (MDA) content both in thoracic aortae. GbE prevented the leakage of LDH and the increase of MDA content in cultured endothelial cells in a concentration-dependent manner. GbE also markedly increased epoprostenol level in cultured endothelial cells treated with LPC., Conclusion: GbE protected endothelial cells against LPC-induced damage due to reduction in lipid peroxidation and facilitation of synthesis and/or release of epoprostenol.

In this paper, the finite difference Poisson-Boltzmann (FDPB) method with four dielectric constants is developed to study the effect of dielectric saturation on the electrostatic barriers of the permeation ion. In this method, the inner shape of the channel pore is explicitly represented, and the fact that the dielectric constant inside the channel pore is different from that of bulk water is taken into account. A model channel system which is a righthanded twist bundle with four alpha-helical segments is provided for this study. From the FDPB calculations, it is found that the difference of the ionic electrostatic solvation energy for wider domains depends strongly on the pore radius in the vicinity of the ion when the pore dielectric constant is changed from 78 to 5. However, the electrostatic solvation energy of the permeation ion can not be significantly affected by the dielectric constant in regions with small pore radii. Our results indicate that the local electrostatic interactions inside the ion channel are of major importance for ion electrostatic solvation energies, and the effect of dielectric saturation on the electrostatic barriers is coupled to the interior channel dimensions.

Effects of EGb on cultured bovine aortic endothelial cells (BAEC) damaged by lysophosphatidylcholine (LPC) were investigated. When endothelial cells were incubated with LPC (2.5 micrograms.ml-1) for 24 h, the endothelial cells turned round pyknotic, exfoliated and broken, and the contents of malondialdehyde (MDA), lactate dehydrogenase (LDH) and plasminogen activator inhibitor (PAI) were markedly increased and the superoxide dismutase (SOD) activity was inhibited. Treatment with EGb at concentrations of 125 and 250 micrograms.ml-1, caused a reduction in MDA, LDH and PAI contents, while the SOD activity in the medium was increased and the morphologically damaged BAECs were alleviated. These results suggest that EGb afforded protection against BAECs damages induced by LPC and that the protective effect of EGb may be due to anti-lipid peroxidation via free-radical scavenging activity.

Aim: To investigate the mechanisms of anti-inflammatory effect of matrine (Mat), its effects on mouse splenocyte proliferation, and release of interleukin-1 (IL-1) and interleukin-6 (IL-6) from mouse peritoneal macrophages., Methods: Splenocyte proliferation was assayed by [3H] TdR incorporation. IL-1 and IL-6 activities were measured by thymocyte proliferation assay and B9 cell proliferation MTT colorimetric method, respectively., Results: Mat (125-500 mg.L-1) obviously inhibited concanavalin A (Con A, 5 mg.L-1)- and lipopolysaccarides (LPS, 10 mg.L-1)-induced splenocyte proliferation and LPS-induced release of IL-1 and IL-6 from mouse peritoneal macrophages., Conclusion: Mat inhibited splenocyte proliferation and release of IL-1 and IL-6 in vitro.

Guan-fu base A (GFA) is a terpenoid alkaloid isolated from the tuber of Aconitum coreanum, which has been shown to prolong cardiac repolarization in vivo and in vitro. In the present study, the effects of GFA on the delayed rectifier current (Ik) were investigated using the whole cell patch-clamp technique in isolated guinea pig ventricular myocytes. In the presence of CdCl2 100 mumol.L-1, Ik was observed upon depolarizing pulses to +50 mV from a holding potential -40 mV for variable duration (550, 1100, 1650, 2200, 2750, 3300, 3850 ms). The magnitude of Ik after a 2200 ms pulse was 293 +/- 90 pA prior to drug and 227 +/- 59 pA in the presence of GFA 100 mumol.L-1. In a 3850 ms pulse, the magnitude of Ik decreased from 290 +/- 90 to 231 +/- 66 pA after exposure to GFA. The inhibitory effects of GFA on Ik was not dependent on the duration of depolarization. The inward rectifier current (Ik1) was not affected by GFA 100 mumol.L-1. It is concluded that GFA has inhibitory effects on Ik, which may contribute to its prolongation of cardiac repolarization.

A study was conducted on the effects of Zhengda Zhenhua 851-R (ZZ-851-R) oral liquor on middle aged-old patients with Kidney and Spleen Deficiencies. It was found that ZZ-851-R was able to relieve the symptoms of aging, improve the memory and fluency of speech, the activity of superoxide dismutase (SOD) GSH and GSH-peroxidase (GSH-Px) increased remarkably and serum lipid peroxide (LPO) level decreased significantly. Improvements of immunity, function of the pituitary-gonad axis were also noticed in the study, with decreased E2/T ratio and improved ability of total antioxydation. In summary, the ZZ-851-R has the effect of antisenility, without obvious side-effect.

We studied p53 overexpression in a series of 99 primary oesophageal squamous cell carcinomas (28 well-differentiated, 42 moderately-differentiated and 29 poorly-differentiated squamous cell carcinomas) from Chinese patients using the p53 protein specific mouse monoclonal antibody DO-7 on paraffin sections. The p53 protein was detected in 30% (30 cases) of the tumours. A significantly higher positive rate was noted in the poorly-differentiated tumours (11% for the well-differentiated, 31% for the moderately-differentiated and 48% for the poorly-differentiated tumours). In addition, strong positive p53 staining was identified only in the less differentiated tumour cells in the periphery of the tumour cell nests in all the cases and the expression was weaker in the better differentiated foci. The central keratinizing areas and the immediately adjacent tumour cells were always negative for p53. The adjacent normal oesophageal mucosa was all negative for p53 protein but the non-invasive dysplastic epithelium next to the tumours could also be strongly positive for p53 protein (four out of 14 cases in which the dysplastic epithelium adjacent to the tumour was adequately sampled). In two out of these four cases, the dysplastic epithelium showed staining for p53; even the adjacent invasive tumour was negative for p53. It is concluded that there is a strong relationship between p53 overexpression and tumour cell differentiation in oesophageal squamous carcinoma and overexpression of p53 can occur in non-invasive tumour cells.

A study was conducted on the effects of Zhengda Zhenhua 851-R oral liquor on the improvement of memory and fluency of language of patients suffering from Kidney Deficiency and control group. It was found that the treated group did better in memory tests and the index of mental quotient (MQ) was higher than that of control group. They had markedly higher scores in the tests of directional memory which requires one's initiative and the free recollection of pictures. The scores achieved by the treated group were significantly higher than that of control on the tests of the fluency of language and expressions, particularly with words of different categories. The results showed that Zhengda Zhenhua 851-R oral liquor obviously had the function of improving the memory and fluency of language for Kidney Deficiency patients.

Phytolacca acinosa polysaccharides I (PAP-I), a kind of purified polysaccharides, isolated from Phytolacca acinosa Roxb was found to significantly augment the cytotoxicity of murine splenocytes and interleukin-2 (IL-2) activated splenocytes against P815 tumor cells in vitro. The optimal concentration of PAP-I was 1 microgram.ml-1 and the peak level of the cytotoxicity against P815 tumor cells was reached on d 3-5. The supernatants collected from splenocytes cultured with PAP-I alone or in combination with IL-2 showed no effect on the cytotoxicity against P815 tumor cells. Splenocytes from mice injected ip with PAP-I, 5, 10 and 50 mg.kg-1, thrice a week produced more cytotoxicity against P815 and L929 tumor cells compared with the control group. PAP-I ip was shown to significantly increase IL-2 activated killer cell activity (LAK) against P815 tumor cells. The higher the dosage of PAP-I, the more potent the LAK activity was observed. These results confirmed that PAP-I can augment the cytotoxicity of murine splenocyte against tumor cells and LAK activity and warranted further evaluation of its clinical usefulness.

Guan-fu base A (GFA) is a terpenoid alkaloid isolated from the tuber of Aconitum coreanum in our institute. GFA (20-30 mg.L-1) reduced the ventricular tachycardia (VT) and ventricular fibrillation (VF) rate induced by K(+)-free and high Ca2+ solution in Langendorf heart of rats. Pretreatment of conscious rats with GFA 2.5-10 mg.kg-1 iv, increased the amount of beiwutine necessary to produce arrhythmias. Ouabain-induced VT in conscious dogs was reverted to sinus rhythm in 1-2 min by iv GFA 9-10 mg.kg-1. GFA 10-20 mg.kg-1 iv was also found to be effective in protecting anesthetized dogs from atrial fibrillation induced by topical application of ACh. GFA 10 mg.kg-1 iv obviously decreased heart rate and prolonged the P-R interval, but slightly affected the myocardial contractility in anesthetized dogs. GFA showed no obvious effect on stroke volume and cardiac output in conscious dogs. In conclusion, GFA showed therapeutic and prophylactic effect on different models of experimental arrhythmias without causing marked effect on myocardial contractility.

From the air-dried roots of Glycyrrhiza glabra L. (Leguminosae) collected in Xinjiang province, China ("Shinkyo-Kanzo" in Japanese), five new flavonoid compounds named glucoliquiritin apioside (1) (a flavonone bisdesmoside), prenyllicoflavone A (5) (a bisprenylflavone), shinflavone (7) (a prenylated pyranoflavanone), shinpterocarpin (9) and 1-methoxyphaseollin (12) (both pyranopterocarpans), were isolated together with eight known saponins, seven known flavonoid glycosides, and eleven flavonoids. The structures of the new compounds have been elucidated on the basis of their chemical and physicochemical properties.

In this study we compared the expression of p53 in six early placentas and eight hydatidiform moles using Northern blotting. A higher expression of p53 in hydatidiform moles as compared to normal placentas of comparable gestational age was observed. Immunohistochemical studies did not detect mutant protein of p53 in the hydatidiform moles. DNA sequencing was performed on four of the hydatidiform moles with increased expression of p53, but no mutations could be detected. The possible role of p53 in the pathogenesis of hydatidiform mole is discussed.

In this study, calf aortic endothelial cells (ECs) were cultured in vitro to study the ECs damages induced by exogenous oxygen free radical (OFR), and the protective effects of ginsenosides. Exogenous OFR was generated by three methods: enzyme reaction (xanthine-xanthine oxidase), chemical reaction (Cu(2+)-ascorbate) and electrolysis. The experimental results indicated that the xanthine-xanthine oxidase method is most suitable for the study of free radical mediated ECs damages. Addition of ginsenosides (40 microliters.ml-1) reduced the concentration of MDA in the cultured ECs, while the 6-keto-PGF1 alpha content in the medium was reduced (P > 0.05) and the morphologic damages of the ECs was alleviated. It is concluded that ginsenosides exerted a protective effects on ECs damages against lipid peroxidation, and ginsenosides might play an important role in antiatherosclerosis through its protective effect on endothelial cells.

From the air-dried roots of Glycyrrhiza uralensis Fischer collected in Xinjiang province, China ("Shinkyo-Kanzo" in Japanese), a new oleanene-type triterpene oligoglycoside named licorice-saponin L3 and a new chalcone oligoglycoside named isoliquiritin apioside were isolated together with glycyrrhizin, 18 alpha-glycyrrhizin, apioglycyrrhizin, araboglycyrrhizin, licorice-saponins A3, E2, G2, and H2, and six known flavonoid glycosides. On the basis of chemical and physicochemical evidence, the structures of licorice-saponin L3 and isoliquiritin apioside were elucidated as 3 beta-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1--> 2)-beta-D-glucuronopyranosyloxy]-22 beta-acetoxy-24-hydroxyolean-12-en-30-oic acid (1) and 4-O-[beta-D-apiofuranosyl(1-->2)-beta-D- glucopyranosyl]isoliquiritigenin (6), respectively.

The expression of proliferating cell nuclear antigen (PCNA) in human trophoblastic disease was assessed immunohistochemically in tissue from 29 spontaneous abortions, 33 partial moles, 40 complete moles and 23 choriocarcinomas using the monoclonal antibody PC10. PCNA immunoreactivity occurred predominantly in the cytotrophoblasts in each of the four types of tissues. Quantitative analysis showed that the choriocarcinoma group gave a statistically significant higher PCNA index than the other three. There was no significant difference between the groups of spontaneous abortion, partial or complete mole. Sixteen of the 73 patients with partial and complete moles developed persistent gestational trophoblastic disease and there was no significant difference between the patients requiring chemotherapy and those who did not. We conclude that choriocarcinoma has a significantly higher PCNA proliferative index whilst hydatidiform moles cannot be distinguished from abortions by such analysis. The PCNA index does not appear to be useful in predicting the progression of molar pregnancies to persistent trophoblastic diseases.

Guan-fu base A (GFA) is a terpenoid alkaloid isolated from the tuber of Aconitum coreanum in this institute. GFA exhibited anti-arrhythmic effects in various experimental arrhythmia animal models, and bradycardic actions. In this paper, the hemodynamic action of GFA was investigated. GFA 20 mg.kg-1 iv decreased in heart rate from 420 +/- 51 to 305 +/- 60 bpm (P less than 0.05). The changes of SBP, DBP, LVSP, +/- dP/dtmax, and LVEDP were much smaller or insignificant. GFA (1, 3, 10, 30, 60 mg.kg-1 cumulative iv) increased the heart periods (HP) and QT-intervals in a dose-dependent manner, accompanied by a small increase in PQ-interval, but did not affect QRS complex. The increase in HP from 138 +/- 11 to 321 +/- 48 ms (P less than 0.01) was mainly due to a prolongation of the diastolic period from 22 +/- 12 ms to 156 +/- 46 ms (P less than 0.01). The triple product of HR x LVET x SBP was also decreased with every dose of GFA. This hemodynamic profile suggests that the bradycardic action of GFA can reduce myocardial oxygen consumption and improve myocardial blood supply, which may be of use in certain cardiac patients.

The first epidemic of dengue in China associated with significant severe and fatal hemorrhagic disease which met the World Health Organization case definition occurred on Hainan Island in 1985-1986. The epidemic began in Zhan County in September 1985, spread throughout the coastal areas, and ultimately involved 13 counties and cities of the island in 1986. The mosquito vector was Aedes aegypti. The morbidity associated with dengue infection on Hainan Island was 1,913 per 100,000 residents, with a case fatality rate of 0.25%. Severe disease was more prevalent in the 10-29-year-old age group. Principal clinical features in laboratory-confirmed cases were fever, osteoarthralgia, hemorrhage and/or shock, and thrombocytopenia. Complications such as acute intravascular hemolysis, diffuse intravascular coagulation, hemoconcentration, pleural effusion, altered mentality, and pneumonia were also observed. One hundred twenty-five isolates of dengue 2 virus were recovered from acute-phase serum samples from 278 patients, and 5 strains of this same virus serotype were isolated from 5 pools of adult Ae. aegypti.

Guan-fu base A (GFA) is a new alkaloid isolated from the tuber of Aconitum coreanum in our institute. Its effects on spontaneous electrical discharge rate of intact sinoatrial node preparations were investigated. Unipolar Ag-AgCl2 electrodes and DC-amplification were used to record unipolar electrograms from the endocardial surface of the isolated right guinea pig atria. GFA (4.29-214.5 micrograms/ml) decreased the spontaneous electrical discharge rate of sinoatrial node in a dose-dependent manner. The most effective concentration (214.5 micrograms/ml) of GFA resulted in sinus rate of 115 +/- 8 bpm (n = 7, control rate 208 +/- 13 bpm) within 30 min. Low external Ca2+ (0.18 mmol/L) enhanced the rate in lowering effect of GFA, in contrast with high external K+ (10.8 mmol/L) diminishing the effect of GFA. The ratios of IC30 of negative inotropic effects over IC30 of negative chronotropic effects were 9.38 for GFA and 1.73 for verapamil. GFA antagonized the positive chronotropic effect of isoproperenol but did not antagonize the positive inotropic effect of isoproterenol. The consequence of lowering sinus rate by GFA was not interfered by propranolol (0.15 micrograms/ml) or atropine (0.05 micrograms/ml). These results suggest that the bradycardia by GFA is a direct effect on sinoatrial node, but not due to the calcium channel block or beta adrenoceptor block.

In 75 patients with subacute fulminant hepatitis B (SAFH), HDAg positive liver cells were observed in 14 cases (18.67%) by direct enzyme labelled method. It was found further that HDV (delta factor) infection was an important cause in producing massive necrosis of liver cells and superinfection of HDV with hepatitis B was identified as one of the causes of SAFH. This experiment also showed that the number of HDAg positive cells was in direct proportion to the area of liver necrosis. No obvious lymphocytic infiltrations and cytotoxic phenomena around the necrotic foci and HDAg positive cells could be found, while the cytoplasmic type HDAg positive cells showed distinct degeneration or even atrophy. Hence it was suggested that HDV could be a direct pathogenesis. No obvious characteristic changes in morphology of HDV infection could be found.

Determination of antineuronal antibodies was carried out by a solid phase radioimmunoassay, in which the neuronal cells SK-N-SH were cultured as the target antigens, the positive rate in sera and CSF of neuropsychiatric SLE patients being 85% and 77.8% respectively, all with quite high level of antibodies. Although 66.7% sera of SLE patients without CNS involvement were also positive for the antibodies, yet the antibody levels of them were distinctly lower, and only 3 of them showed weak positive reactions in their CSF. It was shown that 90% of neuropsychiatric SLE patients with diffuse CNS manifestations had increased antineuronal antibodies, compared with only 20% in cases with local CNS involvements. The antibody levels both in sera and CSF decreased remarkably following the patients' recovery from the neuropsychiatric attack. It is concluded that the antineuronal antibodies might play a role in the pathogenesis of neuropsychiatric lupus and the determination of them in CSF might be useful in the diagnosis and differential diagnosis of neuropsychiatric lupus.

In continuation of searching for effective antidotes against uranium intoxication, a series of N,N'-bis-[N-carboxymethyl-(2,3-dihydroxy-5-carbomethoxy) benzylaminoacetyl]-alpha, omega-diamines was synthesized by reacting 2,3-dihydroxy-5-carbomethoxybenzylamine diacetic acid with diamines of different chain lengths. Their effects on the elimination of uranyl nitrate from rats were tested. Most of them were found to be more effective than the reported uranium chelating agents as Tiron and Phosphicine and compound IIa was shown to be the most promising. The results of pharmacological studies will be published elsewhere.

The presence of enkephalin and substance P-positive neurons and fibers were studied by immunohistochemistry (peroxidase-antiperoxidase or avidin-biotin-peroxidase complex methods) in 26 human fetuses ranging from 11 weeks of gestation to 40 weeks of gestation. Enkephalin-positive neurons were localized in the commissural, medial and intermediate subnuclei as early as 11-12 weeks' gestation. Positive enkephalin fibers were localized around 12 weeks' gestation and in many subnuclei, notably the medial, commissural, intermediate, ventrolateral, ventral and dorsolateral subnuclei. Substance P-positive neurons were localized in the commissural and medial subnuclei around gestation age 13 weeks. Positive substance P fibers appeared even earlier, around 11 weeks of gestation in many subnuclei, notably the medial, intermediate, ventral, ventrolateral and dorsolateral subnuclei. Increase in both enkephalin- and substance P-positive fibers was evident in the later stages of development (e.g. around 26 weeks of gestation). The importance of the early appearance of enkephalin and substance P neurons and fibers of the pain pathways in the major subnuclei connecting with the cardiovascular, gastrointestinal and respiratory functions in the human has to be stressed.

Ultrastructural and morphological alterations of cultured rat beating cardiac myocytes treated with changrolin (CRL), lidocaine (Lid), and amiodarone (Ami) were studied. After the cultures were treated with CRL 100 micrograms/ml for 24 h, the beating of the myocytes stopped, the configuration and fine structure were destroyed, while the nuclei showed pyknotic deformation and reduced in size. The membrane and structures of mitochondria were disrupted and myofibrils fragmented and disrupted. In addition, a lot of vacuoles with characteristic dense particles were found in the cytoplasm. Similar alterations were seen when Lid 1000 micrograms/ml and Ami 50 micrograms/ml were added to the cultures. Normal beating networks of myocytes were examined under inverted microscopy after the cultured cells were treated with CRL 25 micrograms/ml, Lid 250 micrograms/ml or Ami 6.25 micrograms/ml. The ultrastructure of some regions of the myocytes showed very slight damage. The results indicated that the dosage of CRL and Lid generally used in anti-arrhythmic therapy basically exerted no harm to myocytes. However, caution should be taken when Ami was given intravenously, since its effective serum concentration was close to the dosage which could cause slight damage to the ultrastructure of cultured cells.

Follow up results of residue and regression of metastatic cervical lymph nodes in NPC after radiotherapy are presented. All the 453 cases have been followed for more than five years. According to WHO's criteria, the relative 5 year survival rate was 43.9%. 389 of 453 had had lymph node metastases in the neck at the beginning of treatment. At the end of radiation, immediate regression rate of lymph nodes was 53.2%, which was related to lymph node size before radiotherapy. Five year survival rate of those whose lymph node metastases disappeared completely was 48.8% (group 1). There were 182 cases with residual nodes at the conclusion of radiation (140 recorded in detail). The regression rate of nodes was 96.4% (135/140) and the 5 year survival rate of these 140 patients was 40.0% (group 2). There is no significant difference and the long term results are similar in the two groups. Total recurrence rate in the neck was 4.4%: 5.3% in group 1 and 3.8% in group 2 (P greater than 0.05). The treatment results of the local cervical lesions are the same, too. In 182 cases with residual lesions, 121 with 147 clinically evaluable residual nodes, 0.5 approximately 3 cm in diameter, were followed. The regression time of these residual nodes was 2.5 approximately 2.7 months as to geometric mean (the regressive confidence limit 95%). To sum up, according to the routine cervical target dose, some nodes remaining at the of radiation seem to require no boost dose in order to avoid delayed radiation complications. But the residual nodes which recur during follow up would require a prompt retreatment.