Effect of V(2)O(5) on the sintering behavior, microstructure, and electrical properties of (Na(0.5)K(0.5))NbO(3) ceramics

Well-sintered (Na(0.5)K(0.5))NbO(3)-x mol% V(2)O(5) ceramics (abbreviated as NKN-V) with fine electrical properties were successfully prepared by conventional solid-state reaction through the careful control of processing conditions. The sintering behavior, phase structure, and electrical properties of the V(2)O(5)-doped NKN ceramics were investigated. Results show that when the V(2)O(5) content is 0.6 mol%, the NKN ceramics attained the maximum density of 4.46 g/cm(3) (about 98.9% of the theoretical density) at 1060 degrees C, and therefore possessed enhanced electrical properties. But when the V(2)O(5) content continued increasing, the density decreased. The secondary phase (Na(2)V (6)O(16)) could be detected by XRD analysis in all samples except x = 0 mol%. The Curie temperature of the NKN-based materials was found to decrease with the increase of V(2)O(5). The dielectric properties of NKN ceramics doped with 0.6 and 0.9 mol% V(2)O(5) were better than that of pure NKN ceramics. In addition, annealing treatment was proved to be an effective technique for improving dielectric properties and reducing the leakage current density.

Effects of the sol-concentration on the structural and dielectric properties of Pb(0.3)Sr(0.7)TiO(3) thin films derived by the sol-gel method

Pb(0.3)Sr(0.7)TiO(3)(PST) thin films were deposited on Pt coated Si(100) substrates by sol-gel techniques using different sol-concentrations. The structural and dielectric characteristics of lead strontium titanate (PST) thin films as a function of the sol concentration were investigated. PST thin films reveal a columnar texture through the thickness when the sol-concentration is lower than 0.30 M. PST thin films derived from 0.35 M sol show better dielectric characteristics with the dielectric constant, dielectric loss, tunability, and field of motion (FOM) (tunability/ dissipation) of 200, 0.01, 47% and 47, respectively. The temperature dependence of the dielectric constant, dielectric loss and tunability of PST thin films were investigated in the temperature range of -140 to 120 degrees C exhibiting a dielectric peak of about -45 degrees C.

Oxidative stress pathways highlighted in tumor cell immortalization: association with breast cancer outcome

An improved understanding of cell immortalization and its manifestation in clinical tumors could facilitate novel therapeutic approaches. However, only rare tumor cells, which maintain telomerase expression in vitro, immortalize spontaneously. By expression-profiling analyses of limited-life primary breast tumor cultures pre- and post-hTERT transduction, and spontaneously immortalized breast cancer cell lines, we identified a common signature characteristic of tumor cell immortalization. A predominant feature of this immortalization signature (ImmSig) was the significant overexpression of oxidoreductase genes. In contrast to epithelial cells derived from low histologic grade primary tumors, which required hTERT transduction for the acquisition of ImmSig, spontaneously immortalizing high-grade tumor cultures displayed similar molecular changes independent of exogenous hTERT. Silencing the hTERT gene reversed ImmSig expression, increased cellular reactive oxygen species levels, altered mitochondrial membrane potential and induced apoptotic and proliferation changes in immortalized cells. In clinical breast cancer samples, cell-proliferation-pathway genes were significantly associated with ImmSig. In these cases, ImmSig expression itself was inversely correlated with patient survival (P=0), and was particularly relevant to the outcome of estrogen receptor-positive tumors. Our data support the notion that ImmSig assists in surmounting normal barriers related to oxidative and replicative stress response. Targeting a subset of aggressive breast cancers by reversing ImmSig components could be a practical therapeutic strategy.

Identifying susceptibility genes using linkage and linkage disequilibrium analysis in large pedigrees

Linkage and linkage disequilibrium tests are powerful tools for mapping complex disease genes. We investigated two approaches to identifying markers associated with disease. One method applied linkage analysis and then linkage disequilibrium tests to markers within linked regions. The other method looked for linkage disequilibrium with disease using all markers. Additionally, we investigated using Simes' test to combine p-values from linkage disequilibrium tests for nearby markers. We applied both approaches to all replicates of the Genetic Analysis Workshop 12 problem 2 isolated population data set. We reported results from the 25th replicate as if it were a real problem and assessed the power of our methods using all replicates. Using all replicates, we found that testing all markers for linkage disequilibrium with disease was more powerful than identifying markers that were in linkage with disease and then testing markers within those regions for linkage disequilibrium with the implementations that we chose. Using Simes' test to combine p-values for linkage disequilibrium tests on correlated markers seemed to be of marginal value.

[The development of clinical application of the rejuvenator and a study of its mechanism for the treatment of functional erectile dysfunction]

In this paper, we describe the development and clinical application of the Rejuvenator and report the result of our study on its mechanism for the treatment of functional erectile dysfunction (FED). The Rejuvenator, which can be used both at home and in hospitals to treat patients with FED, was developed on the basis of our clinical practice in the light of the modern theory of traditional Chinese medicine and by integrating multiple techniques of engineering science. It works by means of the paraoral use of the special herbal medicine, electro-magnetic effects, thermal moxibustion and drug-ingression. 2250 patients with FED received the treatment. Using combined electro-neurophysiological techniques, pulsed ultrasound Doppler and microcomputer image-scanning, we further studied the mechanism of the Rejuvenator for the treatment of FED. The total effective rate was 92%. The clinical data and result of study indicate that the Rejuvenator for the patients with functional erectile dysfunction is a safe, effective and scientific new method.

Nationality differences in distributions of serum lipids, lipoproteins and apolipoproteins levels in Xinjiang China

OBJECTIVE

To reveal the distribution characteristics of serum lipids, lipoproteins, and apolipoproteins levels in different nationalities.

METHODS

Quantitative levels of those traits mentioned above were determined and body height (H), weight (W) and body mass index (BMI = W/H2) were assessed in 773 Kazaks (men 360 and women 413) and 911 Han nationality (men 466 and women 445) from the Xinjiang Autonomous Region of China.

RESULTS

Kazaks men and women, respectively, had significantly higher serum levels of HDL-c and ApoA1 (all P < 0.001) and significantly lower serum levels of TG (men P < 0.01, women P < 0.001), Lp(a) (all P < 0.005), ApoB (men P < 0.005, women P < 0.001) and ApoB/A1 (men P < 0.01, women P < 0.001) than their Han nationality controls. The threshold points of ApoA1 (< 1.2 g/L) and ApoB (> 1.2 g/L) are higher in Hans than in Kazaks for ApoA1 (20.7 vs 9.8%) and ApoB (18.6 vs 14.3%); the serum levels of TG, HDL-c, Lp(a), ApoA1 and ApoB/A1 are all closely correlated with nationality (P < 0.001, P = 0.001, and P < 0.05, respectively).

CONCLUSION

The results suggest that the nationality differences exist in serum levels of lipids, lipoproteins, and apolipoproteins, and Kazaks have a superior serum lipid pedigree to Hans. This differences may come from genetic differences, which affect the serum levels of lipids, lipoproteins, and apolipoproteins by controlling lipid metabolism patterns. Future study will be needed to dissect to the role of genetic factors on serum lipids.

[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.