[The therapeutic effects and postoperative complications of cataract surgery in Laiwu City]

OBJECTIVE

To decrease the prevalence of blindness and low vision in Laiwu City.

METHODS

The therapeutic effects and postoperative complications of each method of cataract surgery were investigated and statistically analyzed. The cases with postoperative complications were treated after surgery.

RESULTS

In the investigation, 1,274 eyes of 1,089 cases had undergone cataract surgeries, including couching for cataract, intracapsular cataract extraction (ICCE), extracapsular cataract extraction (ECCE) and ECCE with intraocular lens implantation. The prevalence of blindness and low vision was 4.87% and 23.70%, respectively. There were postoperative complications in 650 eyes (51.02%). They were corneal decompensation, secondary glaucoma, opacity of posterior capsuler, cystoid macular edema and retinal detachment. After treatment for the postoperative complications, the prevalence of blindness and low vision was decreased to 1.96% and 6.01%, respectively. The cases having escaped the blindness and handicap after treatment were lowest in the groups of couching and ICCE.

CONCLUSIONS

The survey on the population having undergone cataract surgery in rural district is important. The postoperative complications can be treated in time and the prevalence of blindness and low vision can be decreased.

Ether phospholipid-AZT conjugates possessing anti-HIV and antitumor cell activity. Synthesis, conformational analysis, and study of their thermal effects on membrane bilayers

The 1-O-hexadecyl-2-O-methyl-sn-glyceryl phosphodiester AZT 4 and hexadecyl-phosphodiester AZT 5 derivatives were synthesized and found to be active against HIV-1, HIV-2, and tumor cell proliferation. Compared to AZT, compound 4 possessed ca. 10-fold lower anti-HIV activity and ca. 10-fold higher anti-tumor cell activity. Compound 5 was 10-fold less potent than compound 4 in both biological tests. In an attempt to correlate biological activity of compounds 4 and 5 with structure, their conformational and thermal effects on membrane bilayers were compared using a combination of NMR spectroscopy, computational analysis, and Differential Scanning Calorimetry. The obtained results showed that compound 4 adopts a compact conformation in which the alkyl chain, the 2-methoxyglyceryl functionality, and the methyl group of thymine are in spatial proximity, while analogue 5 possesses a less compact conformation of the nucleoside base and the alkyl chain. The presence of the 2-methoxyglyceryl group in compound 4 may augment its potency by inducing a turn of the alkyl chain stabilized by hydrophobic interactions. The DSC scans show that conjugate 4 affects less effectively the thermotropic properties of model membrane bilayers than compound 5. This may be attributed to the fact that compound 4 is incorporated in a compact conformation and does not perturb significantly the trans:gauche isomerization of the membrane phospholipids. In contrast, conjugate 5 may enter with a less compact conformation and perturb more the membrane bilayers.

Effect of five flavonoid compounds isolated from Quercus dentata Thunb on superoxide generation in human neutrophils and phosphorylation of neutrophil proteins

Effect of five yellow compounds isolated from Quercus dentata on superoxide generation and protein phosphorylation in human neutrophils was investigated. The five yellow compounds examined were Kaempferol 3-O-beta-D-glucopyranoside (B), quercetin 3-O-beta-D-glucopyranoside (DA), Kaempferol 3-O-(6"-trans-p-coumaroyl)-beta-D-glucopyranoside (D1), Kaempferol 3-O-(2"-6"-di-trans-p-coumaroyl)-beta-D-glucopyranoside (D7) and Kaempferol 3-O-(2",4"-di-acetyl-3"-cis-p-coumaroyl-6"-trans-p-coumaroyl)-beta-D-glucopyranoside (A). D7 suppressed significantly the superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP). D1 and DA suppressed significantly the superoxide generation induced by arachidonic acid (AA). However, the superoxide generation induced by phorbol 12-myristate 13-acetate (PMA) was suppressed by all yellow compounds. When the cells were incubated with fMLP and D7, the tyrosyl phosphorylation of 67, 60, 58 and 38 kDa proteins of the cells was markedly decreased in a concentration-dependent manner.

Interfacing a polymer-based micromachined device to a nanoelectrospray ionization Fourier transform ion cyclotron resonance mass spectrometer

Here we report the design, fabrication, and operation of a polymer-based microchip device interfaced to a nanoelectrospray ionization source and a Fourier transform ion cyclotron resonance mass spectrometer. The poly(methyl methacrylate) micromachined device was fabricated using X-ray lithography to produce a network of channels with high aspect ratios. Fabrication of high aspect ratio channels allows for zero dead volume interfaces between the microchip platform and the nanoelectrospray capillary interface. The performance of this device was evaluated with standard peptide and protein samples. High-quality mass spectral data from peptide and proteins (and mixtures thereof) were obtained without any interfering chemical noise from the polymer or the developers and plasticizers used in the fabrication process. Sample cross-contamination is not a problem using this polymer-based microchip device as demonstrated by the sequential analysis of several proteins. The nanoelectrospray source was operated at flow rates from 20 to 100 nL/min using pressure-driven flow, and uninterrupted operation for several hours is demonstrated without any noticeable signal degradation. The ability to fabricate multiple devices using injection molding or hot-embossing techniques of polymers provides a lower cost alternative to silica-based devices currently utilized with mass spectrometry.

[Determination of DNA-DNA homology among Pseudomonas cocovenenans subsp. farinofermentans with microdilution plate hybridization method]

The DNA-DNA homologies among Pseudomonas cocovenenans subsp. farinofermentans and 11 species in genus Burkholderia were determined with microdilution plate hybridization method. The results showed: the homologies among P. cocovenenans subsp. farinofermentans, B. gladioli and B. cocovenenans were all over 75%. It was advised that these three species were synonym, and should be renamed as Burkholderia gladioli.

[Characterization of the structure of industrial poly(ethylene terephthalate) fibers by polarized FTIR]

The polarized FTIR was applied to characterize the structure of Poly(Ethylene Terephthalate) (PET) yarn for industrial use. The fractions of trans and gauche conformers, the orientation of PET chain in the amorphous region and the overall molecular orientation of the samples, have been determined. The structure development during the process has been revealed.

[A novel apoptotic related gene--homocysteine-induced gene HCY-2]

OBJECTIVE

To investigate the mechanisms resulting in cardiovascular diseases and birth defect.

METHODS

Induced screening and differential display, Northern blot, and immunohistochemistry assay were applied to clone the homocysteine-induced gene HCY-2 and detect the expression of HCY-2 gene respectively.

RESULTS

A novel HCY-induced full length cDNA--HCY-2 which encodes 142 amino acids was obtained from vascular smooth muscle cells of rats. Results of the Northern blot and immunohistochemistry assays suggest that it widely expresses in many kinds of tissues such as heart, kidney, brain, liver, and lung. In vitro, we transferred recombinant HCY-2 gene into endothelial cells and found that it could induce apoptosis and DNA injury. In vivo, HCY-2 gene could induce chicken embryo cells apoptosis and embryo malformation.

CONCLUSIONS

The results indicated that HCY-2 gene might be a novel apoptosis-inducing gene and might be involved in the pathogenesis of cardiovascular diseases and birth defects induced by hyperhomocysteinemia.

[Comparison of immunology effects between live attenuated hepatitis A vaccine and inactivated hepatitis A vaccine]

OBJECTIVE

To study the immunology effects of live attenuated hepatitis A vaccine in different doses and schedules groups, and compare with inactivated hepatitis A vaccine (Havrix, Smithkline).

METHODS

318 susceptible children were enrolled in Guangxi and Hebei province. These subjects were divided into six groups. Each group was vaccinated with either inactivated vaccine or different doses and schedules of live attenuated vaccine. Serum specimens were collected and tested for anti-HAV antibody at different time after the vaccination.

RESULTS

GMT of each group arrived at the peak 1 months after re-vaccination, then declined, and GMT of 6 months after booster dose was still significantly higher than that after primary immunization. Sero-conversion rates in all groups reached 100% after a booster dose, and kept at 6 months after booster dose.

CONCLUSIONS

A booster dose of live attenuated vaccine can induce secondary immune response well. The immunology effects after booster dose are comparable with inactivated vaccine and it should be useful to the immune persistence.

[Protective efficacy of H2 strain live attenuated hepatitis A vaccines in an outbreak of hepatitis A]

OBJECTIVE

To investigate the protective efficacy of H(2) strain live attenuated hepatitis A vaccine (H(2)-strain vaccine) locally produced in an outbreak of hepatitis A (HA).

METHODS

A nonrandomized controlled design was used in a trial for HA vaccination. Five thousand five hundred and fifty-one children at preschool classes and at grades 1 - 3 of primary schools were selected in 14 villages. Epidemiological and serological methods were used to evaluate its protective efficacy of the vaccines and serum immunoglobulin M against hepatitis A virus (IgM anti-HAV) was detected with ELISA for 271 subjects in vaccinated group and 341 in the control one.

RESULTS

An outbreak of HA occurred one year after the vaccination with 26 cases in the vaccinated group, including one vaccine-related case with an attack rate of 0.28% (1/356), and 25 cases in the control group with an attack rate of 5.92% (25/422). The protective efficacy of vaccines was 95.27% (95% confidence interval of 85.83% to 104.72%). Positivity of IgM anti-HAV, i.e., newly-infected cases, was 4.43% (12/271) in the vaccinated group and 13.38% (42/314) in the control group, respectively. Clinically apparent cases accounted for 8.33% (1/12) and 50.00% (21/42) in newly-infected cases in vaccinated and control groups, respectively.

CONCLUSION

Vaccination with H(2) strain vaccines locally produced was effective in reducing occurrence of HA during its outbreak, but not so effective in preventing its infection. A booster dose of HA vaccine should be vaccinated for children in adequate time.

Effect of timosaponin E1 and E2 on superoxide generation induced by various stimuli in human neutrophils and on platelet aggregation in human blood

We have reported that six steroidal saponins isolated from Anemarrhenae rhizoma had various effects on stimulus-induced superoxide generation in human neutrophils. In this paper, two novel steroidal saponins, timosaponins E1 and E2 were isolated from Anemarrhenae rhizoma, and the effects of these steroidal saponins on superoxide generation in human neutrophils were investigated. Timosaponins E1 and E2 significantly inhibited N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner, but not that induced by arachidonic acid (AA). On the other hand, both compounds enhanced superoxide generation induced by phorbol 12-myristate 13-acetate (PMA) in a concentration-dependent manner. The superoxide generation induced by PMA with timosaponins E1 and E2 was suppressed by staurosporine, an inhibitor of protein kinase C, but was not suppressed by genistein, an inhibitor of protein tyrosine kinase. Tyrosyl phosphorylation of a 58 kDa protein, which was increased by fMLP, was inhibited by timosaponins E1 and E2. Timosaponins E1 and E2 also inhibited the generation of a 47 kDa protein and platelet aggregation in human blood. The results suggest that protein tyrosine kinase participates in fMLP-mediated superoxide generation by timosaponin E1- and E2-treated human neutrophils.

[Effects of pinyangmycin, dexamethasone and sodium morrhuate injection on treatment of cavernous hemangioma in maxillofacial regions]

OBJECTIVE

To evaluate the effects of Pinyangmycin, Dexamethasonum and Sodium morrhuate injected homochronouly on treatment of cavernous hemangioma in maxillofacial regions.

METHODS

The medical records of 115 patients with cavernous hemangioma in maxillofacial regions between September, 1996 and September, 1998 were reviewed. Fifty of the patients were men, and 65 were women, with a ratio of 1:1.3. The age of the patients was from 4 months old to 45 years old. 73 of the hemangioma bodies were sited in maxillofacial regions, 42 were sited in oral cavity. The sizes of the lesions varied from 1 cm x 1 cm to 5 cm x 8 cm. Treatment procedure: 1. Preparation: 8 mg Pinyangmycin was dissolved in 5 mg/ml Dexamethasonum and in 4 ml of 1% procain which were ready for use; 2. Injection: 1-5 ml (Pinyangmycin 1.6-8.0 mg) of mixed solution was first injected to the hemangioma, then followed by an injection of 0.5-2.0 ml Sodium morrhuate according to local appearance, size of the tumor and patient's age. Generally, the amount of each injection should not be over 8 mg Pinyangmycin. If the tumor did not subside after an injection, another injection might be repeated every 5-7 days, and this process might be repeated 3-5 times. The total dose of Pinyangmycin should not be over 40 mg.

RESULTS

115 patients were followed up for 6-24 months. 81 of 115 (70.43%) cases were recovered, and 30 (26.09%) cases were basically recovered. 4 (3.48%) cases got improvement. The recovery rate were 96.52%, and the total efficiency was 100%.

CONCLUSION

This method may be a safe, simple and effective therapy to cavernous hemangioma in maxillofacial regions.

Projection linkage from spinal neurons to both lateral cervical nucleus and solitary tract nucleus in the cat

Intracellular recordings from the lumbosacral dorsal horn were made to identify the axonal projection and the afferent innervation of the lateral cervical nucleus (LCN) and solitary tract nucleus (STN) on the spinal neurons of chloralose-anesthetized cats. A total of 49 neurons from laminae III-V in the spinal dorsal horn responded to stimulation of both the LCN and STN. Of these, 28 and 21 neurons responded antidromically and orthodromically to stimulation of the LCN and STN, respectively. Seven of the 28 antidromically activated neurons were followed by one or more responses synaptically driven from the LCN and/or STN. The diameter of these ascending or descending fibers was in the range of A delta fibers. The results indicate that (1) some spinal neurons, namely spinocervical tract-spinosolitary tract (SCT-SST) neurons, issue branched axons of A delta-fibers and dually project to both LCN and STN; (2) some SCT-SST neurons receive innervation from both the LCN and STN; (3) some spinal neurons and interneurons are dually innervated by descending fibers originating from both the LCN and STN, and (4) the convergence and integration between somatic and visceral sensory inputs might occur in the SCT-SST neurons.

[Further survey on efficacy of attenuated live hepatitis A vaccines]

OBJECTIVE

To further survey the protective efficacy of the standard attenuated live hepatitis A vaccines (H(2) strain).

METHODS

Randomized and controlled trials were performed in Fucheng county, Hebei province. A total of 12 036 children were assigned into vaccine group (5 551) and control group (6 485) by cluster sampling. The morbidity of hepatitis A was observed and the blood was collected once hepatitis A showed epidemic to detect anti-HAV IgG and IgM.

RESULTS

During the period of the first 7 months after vaccination, hepatitis A was sporadic, the morbidity of hepatitis A was 0.55/100 000, and only 1 case occurred in the control group and no case in the vaccine group. From January to August 1998, hepatitis A showed epidemic in a township of this county. The morbidities were 0.37% and 6.69% for vaccine group and control group, respectively. The protective efficacy of the vaccine was 94.47%. The ratios of clinical cases to subclinical infections were 1 to 11 and 1 to 1 for vaccine and control groups, respectively (P < 0.05).

CONCLUSION

The H(2) strain vaccine has a very good protective efficacy, and obviously decreases the attack rate, new infection rate and clinical cases by HAV infection.

[Treatment of chronic prostatitis with computerized herbal drug penetrator]

A computerized herbal drug penetrator for chronic prostatitis was designed and developed on the basis of a combination of the authors' clinical practice with modern Traditional Chinese Medicinal theories. The device has integrated many hi-techs of current engineering science. It works by applying special herbal medicine, electro-magnetic effects, thermal moxibustion, perfusion and pulsated massage with water-capsule. The result of using this technique in the treatment of 100 cases has demonstrated its satisfying effectiveness.

Effect of six steroidal saponins isolated from anemarrhenae rhizoma on platelet aggregation and hemolysis in human blood

Six steroidal saponins were isolated from Anemarrhena asphodeloides Bunge (Liliaceae), a traditional chinese medicine, and named anemarrhenasaponin I (An-I), anemarrhenasaponin Ia (An-Ia), timosaponin B-I (TB-I), timosaponin B-II (TB-II), timosaponin B-III (TB-III), and timosaponin A-III (TA-III). The effects of these six compounds on platelet aggregation and hemolysis in human blood were studied. All these compounds provoked remarkable inhibiting effect on platelet aggregation, and activated partial thromboplastin times (APTT) are sensitive to the presence of these six compounds. Using an in vitro system, APTT was delayed with the increment of the concentrations of these six compounds. In these six compounds, only timosaponin A-III appeared a strong effect on hemolysis, and anemarrhenasaponin Ia had a slight effect on hemolysis, other had no effect on hemolysis. These results suggested that these steroidal saponins isolated from Anemarrhena asphodeloides Bunge (Liliaceae) might be used as a novel antithrombotic therapeutic agents in post-myocardial infarction.

[Effects of HCY-2 gene transfer on the development of chick neural tube]

In order to explore the relationship between novel gene HCY-2 and neural tube defects (NTDs) and to investigate whether HCY-2 gene was genotoxic, a mammalian expression vector containing HCY-2 cDNA (2014 bp) was transferred into chick fertilized ovum by using lipofectin reagent, then the biological effects of HCY-2 gene on embryos in culture for 3.5 days were observed. Western blotting and immunohistochemistry were used to analyse the expression and distribution of HCY-2 after gene being transferred. HCY-2 gene (5-20 micrograms/chick ovum) could induce NTDs in organogenesis period. Western blotting and immunohistochemical staining showed that HCY-2 protein could be greatly expressed by day 3.5, the time which NTDs developed, with stronger staining at the site of embryonic brain as compared with controls. Under electron microscope, it was observed that HCY-2 gene could damage embryonic cellular ultrastructures and cause excessive apoptosis of neurocytes. These findings suggested that HCY-2 gene with its product was dysmorphogenic to the neural tube, might be a genotoxic factor or teratogenic agent and should be responsible for chick NTDs and probably human NTDs as well.

Molecule imprinting chiral stationary phase

Molecule imprinting polymers (MIPs) with high chiral selectivity for N(alpha)-protected amino acids were synthesized in polar solvent using acrylamide (AM) or combined functional monomer methacrylic acid (MAA) + vinyl pyridine (VP). Factors that influence the chiral selectivity of MIPs and mechanisms of the chiral recognition process were investigated. It was found that the rigid structure and the polar functional group of the print molecule were very important for the chiral selectivity of MIPs. For MIPs made using a combined functional monomer, ionic and hydrophobic interaction may be responsible for the chiral recognition process in aqueous media. The number of binding sites on MIPs and dissociation constants for the complex of enantiomers and MIPs were determined by frontal chromatography analysis.

Hyperhomocysteinemia and hyperlipidemia in coronary heart disease

OBJECTIVE

To examine the relationship between coronary heart disease (CHD) and serum lipid, plasma homocysteine (HCY) as well as the factors related to HCY metabolisms.

METHODS

The mutation of the 677C-->T transition of 5, 10-methylenetetrahydrofolate reductase (MTHFR) was determined by PCR-based assay. Whole-blood and plasma folate and plasma vitamin B12, as cofactors of MTHFR, were determined by radio-immunologic assay. Plasma HCY was determined by HPLC.

RESULTS

Patients with CHD had elevated plasma HCY concentrations (17.38 +/- 1.94 mumol/L vs 10.25 +/- 1.57 mumol/L, P < 0.01). In patients with myocardial infarction (MI) and family history (FH) of CHD, plasma HCY were elevated even higher (P < 0.05). Plasma HCY concentrations had significant non-linear inverse correlation with plasma folate and B12 concentrations, i.e. the lower the serum folate or B12 concentrations, the higher the plasma HCY concentrations (P < 0.01). Patients with homozygous mutants had higher plasma HCY concentrations. Patients with CHD had increased serum Chol and LDL-C and Apo-B levels (P < 0.01, P < 0.05 and P < 0.05 respectively). But plasma HCY concentrations had no correlation with serum lipid levels. 24.1% of the patients had high lipid and high HCY level, 25.9% had high lipid level and normal HCY level, 20.4% had normal lipid and high HCY level, and 29.6% had normal lipid and HCY level.

CONCLUSIONS

HCY may have strong association with the genesis of CHD. Low plasma folate and B12 concentrations may induce Hyperhomocysteinemia [HH(e)]. Plasma HCY concentrations have no correlation with serum lipid levels, so HCY may be an independent risk factor. CHD may be induced by different mechanisms and can be classified into hyperlipidemia, HH (e) and normolipidemia, and normohomocysteinemia.

[Sequencing and analysis of 16S rDNA sequences for P. cocovenenans subsp farinofermentans]

In order to fix the phylogenetic taxonomic position of P. cocovenenans subsp. farinofermentans and describe its relationships with other closed species, seven primers were designed to amplify and sequence the 16S rDNA of 4 strains of it by using a clonal sequencing or direct sequencing method. The 16S rDNA sequence of the 4 strains were aligned with the 16S rDNA sequences of other species in genus Burkholderia, and the polygenetic tree was produced by using a Clustal V and treeview software. The results showed that P. cocovenenans subsp. farinofermentans was in a high homology with Burkholderia gladioli and Burkholderia cocovenenans, and they formed an independent phylogenetic clustal of genus Burkholderia.

[Beaded molecule imprinted polymer for stereo isomer separation]

Beaded molecule imprinted polymer (MIP) was made by suspension polymerization. Particles with the size of 50-70 microns in diameter were collected and evaluated in HPLC mode to separate stereo isomers. Stereo isomers cinchonine and cinchonidine were successfully discriminated with selectivity factor of 2.89 and resolution factor of 0.76. Stereo selectivity of the MIP was found to come from both the interaction between the analyte and carboxyl group on the MIP and the similarity between the stereo structure of imprinted molecule and the MIP. The thermal analysis results showed that the MIP had high thermal stability with initial thermal decomposition temperature of 320 degrees C. The pore volume of the MIP was 0.1849 mL/g, the specific surface area was 126.84 sqm/g and the average pore diameter was 5.8 nanometer. Scanning electron microscopy showed that MIP had perfect spherical morphology.

Effect of steroidal saponins of Anemarrhenae rhizoma on superoxide generation in human neutrophils

Effect of six steroidal saponins isolated from Anemarrhenae rhizoma on superoxide generation in human neutrophils was investigated. The steroidal saponins examined were anemarrhenasaponin-I (An-I), anemarrhenasaponin-Ia (An-Ia), timosaponin B-I (TB-I), timosaponin B-II (TB-II), timosaponin B-III (TB-III) and timosaponin A-III (TA-III). An-I, An-Ia, and TB-III suppressed the superoxide generations induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) and arachidonic acid (AA) in a concentration-dependent manner, but enhanced that induced by phorbol 12-myristate 13-acetate (PMA). While TB-II also suppressed and enhanced the superoxide generations induced by fMLP and PMA, respectively, the compound significantly enhanced the AA-induced superoxide generation. TB-I enhanced the fMLP-induced superoxide generation in a low concentration range (peak at 40 microM), gave no effect on the PMA-induced superoxide generation and weakly enhanced the AA-induced superoxide generation. TA-III enhanced the fMLP-induced superoxide generation more than twice as much as that by TB-I in the same concentration range. However, TA-III enhanced the PMA-induced superoxide generation and most significantly suppressed the AA-induced superoxide generation.

Synthesis and evaluation of hapalosin and analogs as MDR-reversing agents

The marine natural product hapalosin and 22 analogs, which incorporated systematic substituent deletions or variations, were prepared. These compounds were evaluated in a cell-based assay for both MDR-reversing activity and general cytotoxicity. Some substituent modifications resulted in lower cytotoxicities, but most structural changes were either detrimental to or did not seriously alter the MDR-reversing activity.

Coral as a carrier for recombinant human bone morphogenetic protein-2

By combining coral with recombinant human bone morphogenetic protein-2 (rhBMP-2), rhBMP-2/coral composite was obtained in this study. Following implantation of the composite into the muscle pouches of mice, cartilage growth was induced in the pores or on the surface of the implants at one week, woven bone at three week and lamellar bone with bone marrow at six week, and coral was absorbed partially. The induced formation of endochondral bone was time-related and rhBMP-2 dose-related. The results of this study indicate that the composite possesses a superior ability of osteogenesis, and coral acts as one of the most suitable rhBMP-2 slowrelease carriers currently available. The composite will be a new type of bone substitute to be used in orthopaedics and maxillofacial surgery.

[Polylactic acid combined with recombinant human bone morphogenetic protein and basic fibroblast growth factor to repair the mandibular defects in rabbits]

OBJECTIVE

To study the effect of basic fibroblast growth factor(bFGF) on bone formation induced by recombinant human bone morphogenetic protein-2(rhBMP-2) in repair of mandibular defects in rabbits.

METHODS

56 adult domestic rabbits were classified into five groups. The mandiblar three-wall defects(1.5 cm x 0.5 cm, full thick) were created in right sides. The defects were implanted with various grafts: PLA/rhBMP-2/bFGF, PLA/rhBMP-2, PLA/bFGF, PLA and no implant as control group. At 2, 4 and 8 weeks after operation, the effectivenesses of defect repaire were observed by histological and roentgenographic analysis.

RESULTS

The composite consisting of three materials stimulated more bone formation than of two materials, and the latter was more than single PLA(at 4 weeks postoperation, P < 0.05). All experimental groups, which had one or two growth factors, were significantly higher compared with control group in every stage of postimplantation.

CONCLUSION

PLA has good biocompatibility, absorbability and osteoconductibility, rhBMP-2 and bFGF are cooperated in bone healing process, and PLA/rhBMP-2/bFGF is a promising bone substitute in clinical uses.

[A study on homozygous deletion, hypermethylation, mutation and expression of p16 gene in human breast cancer]

OBJECTIVE

To investigate the homozygous deletion (HZD), hypermethylation and mutation of p16 gene in human breast cancer and the relationship between the structural alterations of p16 gene and its expression.

METHODS

PCR and PCR-methylation assay with silver staining (PCR-MASS) were used to detect HZD and hypermethylation of p16 gene exon 1 in 60 fresh breast cancers and 24 normal breast tissues adjacent to cancer (as control tissues). PCR-SSCP and DNA sequencing were used for the analysis of p16 gene mutation. Moreover, p16 gene and mRNA were also detected in the 60 cases.

RESULTS

Of the 60 breast cancers, HZD was found in 7 cases, hypermethylation and mutation were found in 16 and 4 cases respectively, and the difference was statistically significant. The positive rates of p16 protein and mRNA in breast cancer were 28/60 and 39/60 respectively.

CONCLUSION

The results demonstrate that several kinds of p16 gene structural changes exist in breast cancer. The structural changes of p16 gene cause abnormal p16 expression, the main mechanisms are hypermethylation, while HZD or mutation are the secondary causes. Abnormal expression of p16 gene then becomes involved in the development and metastasis of breast cancer.

Substrate specificity and stereoselectivity of rat brain microsomal anandamide amidohydrolase

Anandamide amidohydrolase (AAH) catalyzes the hydrolysis of arachidonylethanolamide (anandamide), an endogenous cannabinoid receptor ligand. To delineate the structural requirements of AAH substrates, rat brain microsomal AAH hydrolysis of a series of anandamide congeners was studied using two reverse-phase high-performance liquid chromatography (RP-HPLC) assays developed in our laboratory. Arachidonamide (1) was found to be the best substrate with an apparent Km of 2.34 mM and a Vmax of 2.89 nmol/min/mg of protein. Although anandamide (2) has a similar Km value, its Vmax is approximately one-half that of arachidonamide. N, N-Bis(2-hydroxyethyl)arachidonamide (3) was not hydrolyzed, suggesting specificity for unsubstituted or mono-N-substituted arachidonamides. Analogues with a methyl group at the 1'-position of the ethanolamido headgroup were also found to have greater resistance to enzymatic turnover and therefore increased metabolic stability. The enzyme exhibited high stereoselectivity as the rate of hydrolysis of (R)-alpha-methanandamide (2.4%) (anandamide = 100%) was about 10-fold lower than that of its (S)-enantiomer (23%). In contrast, (R)-beta-methanandamide was 6-times more susceptible (121%) than the (S)-beta-enantiomer (21%). Interestingly, an inverse correlation was shown between AAH stereoselectivity and the brain cannabinoid receptor affinity as the enantiomers with high receptor affinity displayed low susceptibility to hydrolysis by AAH. Metabolic stability is also imparted to analogues with a short hydrocarbon headgroup as well as to those possessing 2-monomethyl or 2,2-dimethyl substituents. 2-Arachidonylglycerol and racemic 1-arachidonylglycerol were shown to be excellent AAH substrates. To identify AAH inhibitors, hydrolysis of anandamide was also studied in the presence of a select group of cannabimimetics. Of these, (-)-Delta8-THC and SR141716A, a biarylpyrazole CB1 antagonist, were found to inhibit enzymatic activity. These newly defined enzyme recognition parameters should provide a foundation for the rational development of stable, therapeutically useful anandamide analogues with high receptor affinity.

Polymerase chain reaction-based deletion screening of bisulfite (sulfur dioxide)-enhanced gpt-mutants in CHO-AS52 cells

In this study, we have examined the mutagenicity of bisulfite (sulfur dioxide) at the xathine-guanine phosphoribosyl transferase locus (gpt) in the pSV2 gpt-transformed CHO cell line, AS52. Our results provide evidence for bisulfite as a weak gene mutagen because the chemical at high doses and at high cytotoxicity causes a 4-fold increase in mutant frequency (MF) and less than a doubling of the gpt gene deletion frequency compared to control. We suggest that the increase of MF in bisulfite-treated cells results from bisulfite activity,as a comutagen, enhancing the induction effect of unknown endogenous or exogenous factors on spontaneous mutagenesis of AS52 cells. For the spontaneous, 5 mM bisulfite- and 10 mM bisulfite-enhanced spontaneous mutants in AS52 cells, the percentage of total deletion mutations of the gpt gene is 36%, 44% and 65%, respectively

Structural and functional analysis of a MADS box containing genomic DNA sequence cloned from rice

A putative MADS box gene (RgMADS1) was cloned by screening a rice genomic library with a heterogeneous MADS box probe derived from Antirrhinum majus squamosa gene. Sequencing and Southern analysis showed that RgMADS1 contains a highly conserved MADS box sequence, - whereas the rice genome contains numbers of MADS box genes. A chimera gene of RgMADS1 under the control of CaMV 35S promoter was constructed and used to transform Arabidopsis. Some transformants exhibited abnormal phenotypes in their flowers, which were reflected in the floral structure, number and setting position. Therefore, RgMADS1 is likely a member of rice MADS box gene family and may be involved in the floral establishment and function control in the rice developmental process.

Production of emotional facial expressions in European American, Japanese, and Chinese infants

European American, Japanese, and Chinese 11-month-olds participated in emotion-inducing laboratory procedures. Facial responses were scored with BabyFACS, an anatomically based coding system. Overall, Chinese infants were less expressive than European American and Japanese infants. On measures of smiling and crying, Chinese infants scored lower than European American infants, whereas Japanese infants were similar to the European American infants or fell between the two other groups. Results suggest that differences in expressivity between European American and Chinese infants are more robust than those between European American and Japanese infants and that Chinese and Japanese infants can differ significantly. Cross-cultural differences were also found for some specific brow, cheek, and midface facial actions (e.g., brows lowered). These are discussed in terms of current controversies about infant affective facial expressions.

[Timosaponins E1 and E2]

By means of silica gel chromatography and HPLC, two compounds were isolated from Anemarrhena asphodeloides Bge.. On the basis of chemical and spectral (MS, 1H, 13CNMR, IR) analyses, their structures were elucidated as (25S)-26-O-beta-D-glucopyranosyl-22-hydroxy-5 beta-furost-3 beta, 15 alpha, 26-triol-3-O-beta-D-glucopyranosyl (1-->2)-beta-D-galactopyranoside (1), and (25S)-26-O-beta-D-glucopyranosyl-22-methoxy-5 beta-furost-3 beta, 15 alpha, 26-triol-3-O-beta-D-glucopyranosyl (1-->2)-beta-D-galactopyranoside (2). They are named as timosaponin E1 (1) and timosaponin E2 (2) respectively. The structure of anemarrhenasaponin-I (A) is briefly discussed. Timosaponins are the main active constituents of Anemarrhena asphodeloides, most of them were shown to can inhibit platelet aggregation.

[Development and applications of high performance membrane chromatography]

Development and applications of high performance membrane chromatography (HPMC) are introduced. Base membranes, membrane geometries and separations of biomolecules using high performance affinity membrane chromatography (HPAMC), high performance ion-exchange membrane chromatography (HPIEMC) and high performance hydrophobic interaction membrane chromatography (HPHIMC) are reviewed. Enantiomeric separation using HPMC are prospected. Seventy-six references are cited.

Production of emotional facial expressions in European American, Japanese, and Chinese infants

European American, Japanese, and Chinese 11-month-olds participated in emotion-inducing laboratory procedures. Facial responses were scored with BabyFACS, an anatomically based coding system. Overall, Chinese infants were less expressive than European American and Japanese infants. On measures of smiling and crying, Chinese infants scored lower than European American infants, whereas Japanese infants were similar to the European American infants or fell between the two other groups. Results suggest that differences in expressivity between European American and Chinese infants are more robust than those between European American and Japanese infants and that Chinese and Japanese infants can differ significantly. Cross-cultural differences were also found for some specific brow, cheek, and midface facial actions (e.g., brows lowered). These are discussed in terms of current controversies about infant affective facial expressions.

[Effect of rodents on reforestation in the moumtain regions near Beijing]

From 1993 until 1995, the influence of rodents on reforestation in the mountain regions near Beijing was studied in order to estimate the pressure of rodents on the seed supply, search for effective ways to decrease the loss of seeds due to consumption by rodents, and increase seed germinating power. It was shown that acorns, apricot pits and nuts are almost entirely carried away from the soil surface by rodents, thus suggesting that rodents have a great impact on the seed supply. When the seeds were sowed at a depth of about 5 cm, many of them were not eaten by rodents; 39% of acrons and 18% of apricot pits germinated on the following year. We propose that deep sowing of seeds may effectively decrease the loss of seeds through consumption by rodents.

[Treatment of arteriovenous malformation by linear accelerator radiosurgery]

OBJECTIVE

To summarize the effectiveness of radiosurgery for cerebral arteriovenous malformations (AVMs).

METHOD

We treated with linear accelerator radiosurgery 17 patients harboring AVMs in the brain. 15 AVMs were located supratentorially and others infratentorially. All the patients were treated with single fraction. The doses at AVM margin were 15 to 30 Gy.

RESULT

AVMs disappeared in 13 of the 17 patients, reduced in 3 and unchanged in only 1 at 2 year follow up. Vasogenic edema observed in 2 patients, their neurologic deficits were all improved with steroid.

CONCLUSION

Linear accelerator radiosurgery is effective in dealing with cerebral AVMs. It provides with a new means of treatment for AVMs which can't be effectively treated with microsurgery and embolization.

[Immunogenicity and efficacy trials of live attenuated hepatitis A vaccines]

OBJECTIVE

To study two live vaccines, H2 and LA-1 strains, both attenuated in growth on human diploid cell culture at lower temperature (32 degrees C).

METHODS

Randomized, controlled trials were performed among half million children. 135,340 children were divided into vaccine or control groups by individual and 360,012 by cluster. Those susceptibles with negative anti-HAV were bled at 2-6 months after the vaccination and blood test for anti-HAV.

RESULTS

37 hepatitis A cases were found in the control group. The protective efficacy of the two vaccines was 100%, and the 95% lower confidence limit (one sided) of combined efficacy of the two vaccines was 92.1%, that was comparable with the two inactivated vaccines produced by SmithKline beecham or Merck Sharp Dhome.

CONCLUSION

The vaccines are safe, and the seroconversion to H2 strain (10(7.0) TCID50) and LA-1 strain (10(6.75) TCID50) is 94.87% and 83.16% respectively.

[Expression and mutation of p53 and H-ras genes in the carcinogenesis and development of gastric adenocarcinoma induced by MNNG in rats]

OBJECTIVE

To investigate the effect of p53 and H-ras genes in the carcinogenesis of and development of gastric cancer induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Wistar rats.

METHODS

The expression of p53 and H-ras genes in normal mucosa, precancerous lesions and induced-cancers were studied immunohistochemically. DNA isolated from the precancerous lesion and tumors were analysed by PCR-SSCP for exon 5-8 of p53 gene and exon 1 and 2 of H-ras gene.

RESULTS

p53 protein were detected in 50% (20/40) of the gastric cancers studied, but not in the precancerous lesion, while p21 ras protein seen in 23% (9/40) of the gastric cancers and 44% (23/52) of the precancerous lesions. p53 gene mutations were detected in 45% (18/40) of the cancers and none in the precancerous lesions by PCR-SSCP. H-ras gene mutation was not found in either the cancers or the precancerous lesions.

CONCLUSIONS

The activation of ras gene is an early event and may be involved in the carcinogenesis of gastric cancer induced by MNNG. Inactivation of p53 gene may influence the development of the cancer.

Age- and sex-related differences in zinc and lead levels in human hair

The hair of 1518 healthy subjects between newborn and 70 yr old living in Linfen city and the surrounding rural area in Shanxi province, North China, was analyzed by means of a flame atomic absorption spectrophotometer method in order to determine the concentrations of zinc (Zn) and lead (Pb). The collected samples were subdivided on the basis of age, sex, and place of residence (urban and rural). In female hair, the contents of Zn were higher than in male, but the hair Pb concentrations of males were slightly higher than those of females. Age seems to have a different influence on the two elements. The maximum amount of hair Zn was found generally in newborns. From the baby group (<1 yr) to the puberty group (15-19 yr), Zn levels in hair increased with age, and then Zn levels decreased with age from the puberty group to elderly group (61-70 yr). The hair Pb levels were the lowest in newborns, increased with age from newborn to infant (1-2 yr), and then decreased with age from infant to the elderly. It was shown that the hair Pb and Zn levels were inversely related in various age groups, suggesting that there is possibly antagonism between Pb and Zn in the human body. The results also showed the hair Pb levels of subjects living in the urban area, except for newborns, were higher than those of subjects residing in the rural area. However, no difference between the hair Zn contents of the populations residing in urban and rural areas.

Synthetic strategies for the preparation of precursor polymers and of microcapsules suitable for cellular entrapment by polyelectrolyte complexation of those polymers

The production of microcapsules suitable for the entrapment of mammalian cell by means of polyelectrolyte complexation has, of a necessity, led to the development of novel strategies for the preparation of relatively bioinert polymers which complex efficiently under unique conditions to produce a mechanically resilient membrane with efficient transport properties. In this communication we relate a brief overview of capsule-membrane forming systems for the immunoisolation (or potential immunoisolation) of mammalian cells, which are based upon the complexation of polyelectrolyte (PE) polymers; with emphasis on precursor synthesis and relationships between precursor polymer structure and capsule membrane stability.

[The progress of morphological research on the parabrachial nucleus]

In this paper, the progress of morphological research on the PBN, the cytoarchitecture of the PBN, and the fiber connections between the PBN and the spinal, the brainstem, the forebrain and the other nucleus were summarized. Its function in the relationship between the meridian and the internal organ was also assumed.

[Dynamic study of anti-NS5 and ALT in post-transfusion hepatitis C]

In order to study the character and dynamic changes of HCV NS5 antigen in post-transfusion hepatitis C, EIA was established with fusion protein, and different groups of population were investigated. The results showed the positive rate of whole blood donor, normal people, chronic hepatitis C patients and post transfusion hepatitis C patients is 0.0%, 1.66%, 50.7% and 70.5%, respectively. Serial blood samples of 25 cases of acute or chronic post-transfusion hepatitis C were detected, and the results indicated that the antibody of NS5 appeared relatively late, and the serum conversion time was 182.9 +/- 168.5 days. The anti-NS5 positive rate in 1, 3, 6, 12 and 24 months after HCV infection was 28%, 40%, 52%, 68% and 76%, respectively. The positive rate of anti-NS5 in sera with HCV RNA was 61.9%. Analysis on the appearance of antibody to the different antibody region of the gene, ALT and HCV RNA showed the dynamic changes of anti-NS5 were corresponding to the serum ALT in some cases, indicating antibody of NS5 appear later and may reflect the disease activity to some extent. The dynamic changes of anti-NS5 are of four kinds: transient positive, intermittent positive, persistent positive and persistent negative in during the two years period.

Chromosomal aberrations and micronuclei in lymphocytes of workers at a phosphate fertilizer factory

The frequencies of chromosomal aberrations (CA) and micronuclei (MN) in peripheral blood lymphocytes of 40 workers at a phosphate fertilizer factory in North China, were studied. HF and SiF4 are the main air pollutants and small amounts of dust containing fluoride, NH3 and SO2 were also present in the factory. It was shown that the chemicals caused an increase in both CA and MN. The mean frequencies per 100 metaphase of major CA type (chromosome rings, translocations, and dicentrics) of the workers and the non-exposed controls were 0.91 and 0.24 (p < 0.01), respectively. The average percentages of lymphocytes with MN of the workers and the controls were 1.55 +/- 0.71 and 0.62 +/- 0.54 (p < 0.01), respectively. Both CA frequency and MN frequency of the workers increased with length of the chemical exposure period up to 10 years.

Effect of a chemical modification on the hydrated adenosine intermediate produced by adenosine deaminase and a model reaction for a potential mechanism of action of 5-aminoimidazole ribonucleotide carboxylase

Using the hydrated adenosine intermediate (6R)-6-amino-1, 6-dihydro-6-hydroxy-9-(beta-D-ribofuranosyl)purine (2) produced by adenosine deaminase (ADA, EC 3.5.4.4) as a starting point, the active site probe and inhibitor platform 5-(formylamino)imidazole riboside (FAIRs, 4) was designed by removal of the-C6(OH)(NH2)-molecular fragment of 2 generated by the early events of the enzyme-catalyzed hydrolysis. FAIRs was synthesized directly from the sodium salt of 5-amino-1-(beta-D-ribofuranosyl)imidazole-4-carboxylic acid (CAIR) along a reaction sequence involving a tandem N-formylation/decarboxylation that may have a mechanistic connection to the Escherichia coli purE-catalyzed constitutional isomerization of N5-CAIR to CAIR. The physical and spectral properties of FAIRs were elucidated, its X-ray crystal and NMR solution structures were determined, and its interaction with ADA was investigated. Crystalline FAIRs exists solely as the Z-formamide rotamer and exhibits many of the same intramolecular hydrogen bonding events known to contribute to the association of Ado to ADA. In water and various organic solvents, however, FAIRs exists as NMR-distinct, slowly interconverting Z and E rotamers. This truncated enzymatic tetrahedral intermediate analog was determined to be a competitive inhibitor of ADA with an apparent Ki binding constant of 40 microM, a value quite close to that (33 microM) of the natural substrate's K(m). The actual species selected for binding by ADA, though, is likely the minor hydroxyimino prototropic form of Z-FAIRs possessing a far lower true Ki value. As the structural features of FAIRs appear well-suited to support its use as a template for constructing active site probes of both ADA and AIR carboxylases, a variety of carbohydrate-protected versions of FAIRs suitable for facile aglycon elaborations were synthesized. The N3-alkylation, N3-borane complexation, and C4-iodination of some of these were investigated in order to assess physicochemical properties that may assist in the elucidation of mechanisms for the AIR carboxylases. The survey of these properties taken together with a reasonable mechanism for the model CAIRs-->FAIRs synthetic transformation is interpreted to support a mechanism for the purE-catalyzed N5-CAIR-->CAIR biosynthetic one that involves a carboxylative sp3-rehybridization of the imidazole C4 atom rather than one possessing a dipole-stabilized C4 sp2 carbanionic intermediate.

[Molecular analysis of spontaneous and arsenite-induced mutations at the gpt locus in Chinese hamster ovary cells]

In this study, we examined the mutagenicity of sodium arsenite at the xathine-guanine phosphoribosyl transferase locus (gpt) in a pSV2 gpt-transformed CHO cell line AS52. The chemical induced a dose-dependent increase of mutant frequency at the locus. Nested PCR analysis revealed that the majority of arsenite-induced AS52 mutants had totally deleted the gpt gene. For the spontaneous, 50 mumol/L arsenite--and 100 mumol/L arsenite--induced mutants in AS52 cells, the percentages of total deletion of the gpt gene were 36.00%, 54.72% and 66.67% respectively. The PCR products of gpt gene from nine 100 mumo/L sodium bisulfite-induced mutants were analyzed with direct DNA sequence technology. The frameshift mutation was identified in two mutants (2/9). No genomic alteration could be found in the structural gene examined in the other 7 mutants, where their molecular alterations probably located in the promoter region.

Electrophysiological evidence that spinomesencephalic neurons in the cat may be excited via spinocervical tract collaterals

Extracellular microelectrode recordings were made from spinomesencephalic tract (SMT) neurons in the lumbosacral spinal cord of cats anaesthetized with chloralose and paralysed with gallamine triethiodide. The SMT cells were antidromically fired from the posterolateral parts of the superior colliculus and the intercollicular region, were located in laminae IV to VIII, and had response properties and axonal conduction velocities similar to those described previously. The effects of stimulating the dorsolateral funiculus of the cervical cord at C3 and rostral C1, below and above the termination of spinocervical tract (SCT) axons in the lateral cervical nucleus, were examined on 33 SMT cells. The strength of stimulation was adjusted so that at C3 it was above threshold for antidromic activation of SCT cells and at C1 was below threshold for activation of the same cells. Seven (21%) SMT neurons were excited from C3 but not from C1. The remaining 26 (79%) were excited from both C3 and rostral C1 and 23 (70% of these) were excited significantly more from C3. That is, 91% of the total sample were either excited only from C3 or more strongly from C3 than from rostral C1. We discuss the possible neuronal systems involved and conclude that the greater excitatory effects from C3 are most likely due to antidromic activation of the SCT. The shortest latency effects from C3 indicate a monosynaptic linkage between SCT cells with the fastest axons and the SMT. The longer latency actions may be due to monosynaptic connexions from SCT cells with slower conducting axons, to di- or polysynaptic actions from SCT cells with fast axons, or a combination of both. SMT cells are another population of spinal neurons, in addition to postsynaptic dorsal column, spinothalamic and dorsal horn spinocerebellar neurons, which receive excitation via SCT collaterals.

[The effect of phenytoin in healing of fracture of rabbits]

It was reported that the systemic use of phenytoin could promote healing of fracture. In order to observe the effect of local application of phenytoin in the healing of fracture, the experiment was performed. Seventy-two rabbits were divided into three groups. Fractures were created on both radius of all rabbits. Group 1, intraperitoneal injection of phenytoin with a dosage of 50 mg/kg per day; Group 2, local use of phenytoin with a dosage of 40 mg/kg was injected in the fracture site every seventy-two hours, and Group 3, injection mormal saline of in the control group. Eight rabbits in each group were sacrificed in the 9th, 16th and 30th days after operation respectively. By X-ray excuiualtion, the healing of fracture was observed. Dry and wet weights of the callus were determined. After HE and Mallory's stain, the samples were examined under microscope. Results showed that both local and systemic use of phenytoin promoted healing of fracture. The effects of phenytoin in the two groups were the same and had no significant difference.

Effect of structural modification of enol-carboxamide-type nonsteroidal antiinflammatory drugs on COX-2/COX-1 selectivity

Meloxicam (5), an NSAID in the enol-carboxamide class, was developed on the basis of its antiinflammatory activity and relative safety in animal models. In subsequent screening in microsomal assays using human COX-1 and COX-2, we discovered that it possessed a selectivity profile for COX-2 superior to piroxicam and other marketed NSAIDs. We therefore embarked on a study of enol-carboxamide type compounds to determine if COX-2 selectivity and potency could be dramatically improved by structural modification. Substitution at the 6- and 7-positions of the 4-oxo-1,2-benzothiazine-3-carboxamide, alteration of the N-methyl substituent, and amide modification were all examined. In addition we explored several related systems including the isomeric 3-oxo-1,2-benzothiazine-4-carboxamides, thienothiazines, indolothizines, benzothienothiazines, naphthothiazines, and 1,3- and 1,4-dioxoisoquinolines. While a few examples were found with greater potency in the COX-2 assay, no compound tested had a better COX-2/COX-1 selectivity profile than that of 5.