[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.

[The synthesis and characters of the 4,5-dihydroxy-o-benzoquino(bis-hydrazone) and their metal complexes]

The complexes of the 4,5-dihydroxy-o-benzoquinones with the metal ion (metal = Mn, Ni, Cu) were synthesized. The structure characterization of these compounds were processed by the IR spectra and thermogravimetric analysis. The experiments of the plant growth of the 4,5-dihydroxy-o-benzoquinones indicated that it is a high-effect plant growth regulator.

[ATR-FTIR studies on the packing film]

FTIR and ATR-FTIR of the packing film have been studied. The dimension of thickness is about 0.034 m/m, the right and wrong sides of this packing film is composed of polypropylene and polyethylene glycol terephthalate, respectively.

Resonance Rayleigh method for the determination of proteins with Orange G

In pH 0.6 - 2.0 HCl-sodium acetate buffer solution, proteins react with an acidic monoazo dye such as Orange G, Methyl Orange, Methyl Red and Orange IV to form a combination product. This results in a significant enhancement of resonance Rayleigh scattering (RRS) and a new RRS spectrum appears. Owing to the fact that Orange G-protein system is the most sensitive, it was taken as an example to study. The RRS spectral characteristics of its combination product and the optimum condition for the reaction were investigated. The intensity of RRS is directly proportional to the concentration of protein in the range of 0 - 5.0 microg/mL. The method has high sensitivity; its detection limits are 2.6 ng/mL for BSA, 3.4 ng/mL for HAS and 7.1 ng/mL for alpha-chymotrypsin, respectively. A new method for the determination of trace amounts of proteins on the basis of RRS spectra has been developed.

Closely related HIV-1 CRF01_AE variant among injecting drug users in northern Vietnam: evidence of HIV spread across the Vietnam-China border

To investigate the nature of recent HIV outbreaks among injecting drug users (IDUs) near the Vietnam-China border, we genetically analyzed 24 HIV-positive blood specimens from 2 northern provinces of Vietnam (Lang Son and quang Ninh) adjacent to the China border, where HIV outbreaks among IDUs were first detected in late 1996. Genetic subtyping based on gag (p17) and env (C2/V3) sequences revealed that CRF01_AE is a principal strain circulating throughout Vietnam, including the provinces near the China border. The majority of CRF01_AE sequences among IDUs in Quang Ninh and Lang Son showed significant clustering with those found in nearby Pingxiang City of China's Guangxi Province, sharing a unique valine substitution 12 amino acids downstream of the V3 loop. This particular subtype E variant, uniquely found among IDUs in northern Vietnam and southeastern China, is designated E(v). The genetic diversity of CRF01_AE distributed in Quang Ninh (1.5 +/- 0.6%) and Pingxiang City (1.9 +/- 1.2%) was remarkably low, indicating the emerging nature of HIV spread in these areas. It is also noted that the genetic diversity of CRF01_AE among IDUs was consistently lower than that in persons infected sexually, suggesting that fewer closely related CRF01_AE variants were introduced into IDUs and, conversely, that multiple strains of CRF01_AE had been introduced via the sexual route. The data in the present study provide additional evidence that HIV outbreaks among IDUs in northern Vietnam were caused by the recent introduction of a highly homogeneous CRF01_AE variant (E(v)) closely related to that prevailing in nearby southern China.

[Effect of vitamin E on morphological variation of retinal ganglion cells after microwave radiation]

To determine the morphological variation in the primary cultured pig retinal ganglion cells induced by microwave and the protection of VE can supply some experiment foundation for study of effect of microwave and its protection. Retinal ganglion cells of pig were cultured in vitro and added VE of different concentration, Each group was taken after 30 mW/cm2 microwave intensity radiated for 1 h in shielded room by 2450 MHz continuous wave physiotherapy machine. Immediately after radiation, the morphological variation of cells was observed by optics microscope and transmission electronic microscope. The result showed that a portion of cells congregated, with their axon disappeared after radiation. Mitochondria and endoplasmic reticulum are detected swelling by transmission electronic microscope. The results showed that A poptosis cells can be observed. Cells of VE added groups had not obvious changes with optics microscope, but could be found that mitochondria swelling lightly and integrate mitochondria cristae by transmission electronic microscope. The results showed that microwave induced the morphological damage in primary cultured retinal ganglion cells, VE could reduced the damage of retina ganglion cells by microwave in some extent.

Study on the preparation of recombinant human HSP70 and its presenting-antigen function

The preparation of recombinant human HSP70 and its presenting-antigen function were investigated. Cultured in glucose-free M9ZB medium and induced with IPTG and lactose at a final concentration of 0.02 mmol/L and 5 mmol/L respectively, the engineered bacteria carrying expression vector of human HSP70 gene expressed rHSP70 at an efficiency fo 60%. After the purification with DEAE ion-exchange chromatography, HSP70 with a purity of higher than 90% was obtained. The purified product could bind tumor-antigen peptide in vitro, and the binding was identified by native PAGE containing 5% glycerol. HSP70-peptide complex could activate lymphocytes to produce specific cytotoxicity to tumor cells, suggesting that the recombinant human HSP70 could be used as an antigen-presenting reagent in tumor therapy.

[The preparations and spectroscopic studies of V-Bi oxides]

The multicomponent compounds V-Bi oxides have been prepared by sol-gel and microwave method, and have been studied by FTIR, NIR FT-Raman and XRD.

[Vibrational frequencies study of the hydroxy-benzoquinones]

In this paper, we report the Ab initio calculation and experimental investigation of the vibrational frequencies of 4,5-dihydroxy-1,2-benzoquinone and 2,5-dihydroxy-1,4-benzoquinone. The main IR and Raman absorption bands of them have been assigned, learned from other strong points to offset one weakness, by combination the program Gaussian 94 and MOPAC. The difference in absorption bands between them has been discussed.

Effects of exercise training on cardiac function, gene expression, and apoptosis in rats

This study determined the effects of exercise training on cardiac function, gene expression, and apoptosis. Rats exposed to a regimen of treadmill exercise for 13 wk had a significant increase in cardiac index and stroke volume index and a concomitant decrease in systemic vascular resistance compared with both age-matched and body weight-matched sedentary controls in the conscious state at rest. In exercise-trained animals, there was no change in the expression of several marker genes known to be associated with pathological cardiac adaptation, including atrial natriuretic factor, beta-myosin heavy chain, alpha-skeletal and smooth muscle actins, and collagens I and III. Exercise training, however, produced a significant induction of alpha-myosin heavy chain, which was not observed in rats with myocardial infarction. No histological features of cardiac apoptosis were observed in the treadmill-trained rats. In contrast, apoptotic myocytes were detected in animals with myocardial infarction. In summary, exercise training improves cardiac function without evidence of cardiac apoptosis and produces a pattern of cardiac gene expression distinct from pathological cardiac adaptation.

The aberrant fusion proteins PML-RAR alpha and PLZF-RAR alpha contribute to the overexpression of cyclin A1 in acute promyelocytic leukemia

Cyclin A1 is a newly discovered cyclin that is overexpressed in certain myeloid leukemias. Previously, the authors found that the frequency of cyclin A1 overexpression is especially high in acute promyelocytic leukemia (APL). In this study, the authors investigated the mechanism of cyclin A1 overexpression in APL cells and showed that the APL-associated aberrant fusion proteins (PML-retinoic acid receptor alpha [PML-RAR alpha] or PLZF-RAR alpha) caused the increased levels of cyclin A1 in these cells. The ectopic expression of either PML-RAR alpha or PLZF-RAR alpha in U937 cells, a non-APL myeloid cell line, led to a dramatic increase of cyclin A1 messenger RNA and protein. This elevation of cyclin A1 was reversed by treatment with all-trans retinoic acid (ATRA) in cells expressing PML-RAR alpha but not PLZF-RAR alpha. ATRA also greatly reduced the high levels of cyclin A1 in the APL cell lines NB4 and UF-1. No effect of ATRA on cyclin A1 levels was found in the ATRA-resistant NB4-R2 cells. Further studies using ligands selective for various retinoic acid receptors suggested that cyclin A1 expression is negatively regulated by activated RAR alpha. Reporter assays showed that PML-RAR alpha led to activation of the cyclin A1 promoter. Addition of ATRA inhibited PML-RAR alpha-induced cyclin A1 promoter activity. Taken together, our data suggest that PML-RAR alpha and PLZF-RAR alpha cause the high-level expression of cyclin A1 seen in acute promyelocytic leukemia. (Blood. 2000;96:3894-3899)

[The preparations and spectroscopic studies of Mo-Fe-Bi oxides]

The multicomponent compounds Mo-Fe-Bi oxides have been prepared by sol-gel and precipitation method, and have been studied by FTIR, NIR FT-Raman and XRD.

[Study on improvement of liver cirrhosis and liver function in hepatolenticular degeneration patients treated with integrated Traditional and Western medicine]

OBJECTIVE

To observe the effects of sodium dimercaptosulphonate (DMPS) plus Gandou tablet, DMPS and calcium disodium ethylene diaminotetraacetate (EDTA) on improving liver cirrhosis and liver function of hepatolenticular degeneration (HLD) patients.

METHODS

One hundred and forty-six HLD patients were divided into A, B, C three groups, and treated with DMPS plus Gandou tablet, DMPS and EDTA respectively, the therapeutic course was 8 weeks for three groups. The ultrasonography of liver, electrophoresis of serum protein and excretion of urinary copper were observed.

RESULTS

The ultrasonography of liver was improved in all groups, the rate of improvement of group A was 54.0%, B was 44.0% and C was 39.1%. The amounts of serum albumin in A and B groups increased (P < 0.01, P < 0.05), and gamma-globulin decreased in all groups (P < 0.05). The excretion of urinary copper increased obviously in all groups (P < 0.01), and A, B groups increased more than that of C group (P < 0.05).

CONCLUSIONS

The de-copper therapy could improve liver cirrhosis and liver function. The effect of DMPS plus Gandou tablet was better than that of DMPS and EDTA.

[Homogeneity study on the Streptococcus suis isolated from human and swine]

OBJECTIVE

To identify S. suis and to evaluate the homogeneity of isolates of S. suis from human and swine.

METHODS

Culture, morphology, API biochemical tests and serum coagulate tests were used. All the 7 strains of streptococcus were confirmed to be S. suis serotype 2. Two strains and 1 strain were isolated from blood and cerebrospinal fluid (CSF) of patients, respectively, while the other 4 strains were obtained from the infected swine or their corpses. Seven strains of S. suis serotype 2 and reference strain SS2 were analyzed by randomly amplified polymorphic DNA analysis with six primers and Rep PCR with four primers and thalli fatty acid profile analysis. Cluster and principal compound analysis of results were performed with RAPD, Phylip and Treeview software.

RESULTS

By analysis on RAPD patterns, a close relationship among 7 strains of S. suis serotype 2 and reference strain SS2 was discovered. Human-born strains and swine-born strains exhibit similar RAPD patterns. There was a same clonal relationship between strains originated from the blood and CFS of the patients. These results were confirmed by thalli fatty acid profile to have genotypic and phenotypic identity.

CONCLUSION

Homogeneity exists among the 7 strains and reference strain SS2.

[The preparations and spectroscopic studies of infrared radiating materials]

ZrO2 and ZrO2-Al2O3 samples have been prepared by precipitation method, and characterized by FTIR, NIR FT-Raman, XRD and IR emission spectra, respectively. The result showed that these samples are the better infrared radiating materials, which have high efficiency and excellent properties. When compared with pure ointment, ZrO2-Al2O3 prepared has more strong infrared emission peaks. The application of infrared radiating materials in ointment may have a good effect on thermal infrared absorption vibration and absorption of medicine by sick part of body.

[Application of indigo disulphonate spectrophotometry on the determination of ozone in indoor air]

Spectrophotometric determination of ozone in indoor air by using indigo disulphonate was investigated. The results showed that the average recovery of ozone was 99% and the relative standard deviation was 2.3% when the concentration of indoor ozone was in the range of 0.2-1.0 microgram/ml. The lowest detection concentration was 0.009 mg/m3 (sampling 20 L) when the range of determination was 0.18-10.0 mg/10 ml.

Effects of VEGF on hemodynamics and cardiac function: characterization and mechanisms

Vascular endothelial growth factor (VEGF), a mitogen specific for endothelial cells, produces beneficial angiogenesis in animal models of ischemic diseases; however, its side effects on hemodynamics and cardiac function may limit clinical use for some indications. This review focuses on the VEGF-induced hemodynamic profile, including hypotension, tachycardia, decreases in cardiac output and stroke volume, and changes in preload and afterload. The hemodynamic effects of VEGF are due to vasodilation and vascular hyperpermeability, which are mainly mediated by nitric oxide. Finally, the regimen or strategy for attenuation or prevention of these side effects is discussed.

Autoimmunity to munc-18 in Rasmussen's encephalitis

Rasmussen's encephalitis (RE) is a rare disease of the central nervous system characterized by severe epileptic seizures, progressive degeneration of a single cerebral hemisphere, and autoimmunity directed against glutamate receptor subunit, GluR3. We report here the identification of high-titer autoantibodies directed against munc-18 in the serum of a single patient with RE previously shown to have anti-GluR3 antibodies. Munc-18 is an intracellular protein residing in presynaptic terminals, which is required for secretion of neurotransmitters. These findings are consistent with the possibility of intermolecular epitope spreading between GluR3, a postsynaptic cell surface protein, and munc-18, a presynaptic intracellular protein. Immune attack on these two proteins, which participate at distinct steps of synaptic transmission, could act in an additive or synergistic manner to impair synaptic function and lead to seizures and neuronal death.

A new cembranolide from the soft coral Sinularia capillosa

A new cembranolide, capillolide (1), and three known cembranolides were isolated from the soft coral Sinularia capillosa collected from the South China Sea. Their structures and the relative stereochemistry of 1 were deduced on the basis of spectroscopic methods.

[Establishment of cisplatin-induced multidrug resistant human epithelial ovarian cancer cell line 3AO/cDDP and its expressions of multidrug resistance proteins]

OBJECTIVE

To establish multidrug resistant ovarian cancer cell line 3AO/cDDP by exposing parent cell line intervally and repeatedly to high-level concentration of cisplatin, and to detect expressions of lung resistance protein (LRP), multidrug resistance-associated protein(MRP) and P-glycoprotein (P-gp).

METHODS

Using the corresponding dose calculated from clinical chemotherapy, we established 3AO/cDDP, with 3AO exposed intervally and repeatedly to high-level concentration of cisplatin at 10 micrograms/ml for 24 hours each time; LRP, MRP and P-gp expressions were detected with flow cytometry(FCM).

RESULTS

3AO/cDDP was established after 4.5 months with stable resistance and the drug resistant index was 1.62 which was similar to clinical resistance degree. Low expression levels of MRP and P-gp were found in both 3AO and 3AO/cDDP, and no statistical difference between the two lines (P > 0.05). However, LRP expression level in 3AO/cDDP was significantly higher than that in 3AO with FCM detection (P < 0.01).

CONCLUSIONS

3AO/cDDP, induced by exposing 3AO to high-level concentration of cisplatin intervally and repeatedly, is an ideal model for investigation of cisplatin resistance. Cisplatin resistance in 3AO/cDDP could be related to high LRP expression and be not associated with MRP or P-gp.

[Observation on curative effect of acute ischemic cerebrovascular disease treated with different dosage of ligustrazine]

OBJECTIVE

To compare clinical curative effect of acute ischemic cerebrovascular diseases (ICVD) treated with different dosage of ligustrazine and to observe the effect of ligustrazine on hemorrheology.

METHODS

Sixty-nine patients with ICVD were randomized into three groups, the Group A, B and C treated with 120 mg, 240 mg and 480 mg of ligustrazine respectively, the clinical curative effect, the changes in nerve function deficit score and hemorrheologic parameters before and after treatment were observed.

RESULTS

The clinical curative effect and improvement of hemorrheologic parameters in Group C were better than those in Group A and B significantly (P < 0.05, P < 0.01 respectively). Ligustrazine also showed obvious effect in lowering blood level of fibrinogen in Group C.

CONCLUSION

Treatment of acute ICVD with large dose of ligustrazine is good in improving clinical effect and hemorrheology, and without side effect basically.

Characterization of demineralized bone matrix-induced osteogenesis in rat calvarial bone defects: III. Gene and protein expression

Our previous studies of rat cranial defect repairs after the implantation of demineralized bone matrix (DBM) have demonstrated that healing occurs initially and principally by the direct induction and proliferation of osteoblasts derived principally from resident mesenchymal stem cells of the dura, and to a lesser extent by resident mesenchymal stem cells of the connective tissues beneath the skin flap. A small amount of cartilage is also synthesized after the direct process of ossification occurs. To further confirm the molecular phenotypes of the repair cells in rat cranial defects, the present study evaluated mRNA expression and synthesis of collagens I, II, and X and osteocalcin in the DBM-induced repair tissue by Northern blot analyses, autoradiography after in vivo (3)H-proline labeling of collagen, and immunohistochemistry. The results demonstrated that osteocalcin mRNA appeared in small amounts by day 4 and continued to increase over the experimental period. Much lesser quantities of collagen types II and X mRNAs appeared by day 6 and day 8, respectively. Collagen type I mRNA was present at all times examined but its expression significantly increased by day 5. Autoradiographic and immunohistochemical studies showed that type II collagen was not detected whereas type I collagen was synthesized on days 3-5. The data provide definitive molecular evidence confirming that the initial and by far the major pathway of cranial defects repair induced by implantation of DBM is by the direct induction of resident mesenchymal stem cells to osteoblasts and the direct formation of bone, which is spatially and temporarily distinct from the later formation of cartilage.

[Synthesis and characterization of the oxidation product of the 1, 2, 3-trihydroxybenzene and its metallic complexes]

The oxidation reaction mechanism of the 1,2,3-trihydroxybenzene was studied by the Ab initio calculation of the quantum chemistry. The derivative of the hydrazine and THBO(the reaction product of the 1,2,3-trihydroxybenzene and H2O2) and its metal complexes were synthesized and characterized by the IR, Raman spectrum and thermogravimetric analysis. The composition of these complexes and the possible structure of THBO were confirmed.

[The synthesis and spectral study of multicomponent heteropoly compounds with Keggin structure]

The Multicomponent heteropoly compounds [Me4N]3 + x[PVxMoyW12-x-yO40]. n(H2O) with Keggin structure have been synthesized, and have been characterized by FTIR and NIR FT-Raman. The vibrational regularity of oxygen-containing bonds (P-Oa, M = Od, M-Ob-M and M-Oc-M) in these heteropoly compounds have been studied. The vibrational frequencies nu as (M = Od) and nu as (M-Ob-M) was shown to prove the reason why the acidity of the heteropoly compounds descended and the oxidization increased by the substitution of V atoms.

[High-affinity glutamate transporters]

High-affinity glutamate transporters are located predominantly in the plasma membrane of neurons and glial cells. They have the capacity to take up glutamate from the extracellular space into the cells against its concentration gradient to terminate glutamatergic transmission and to keep the extracellular glutamate concentration at low levels to protect neurons from glutamate toxicity. As glutamate transporters were recently cloned, the research in this field has been greatly advancing. This article focuses on recent progress in the study of molecular structure, distribution of expression, physiological significance, structure-function relationships of these transporters.

[Determination of the composition distribution of polymer blend films by using microscopic FTIR]

In this paper, PS/PC blend film (about 120 microns thick) and PS/PMMA (about 90 microns thick) blend film were prepared by evaporation the solvent very slowly from polymer blend solution. Different FTIR methods were used to determine the composition distribution along the vertical direction of the films. PS/PC film was firstly sectioned by ultramicrotomy, then the vertical section was measured to determine the composition of every 16 microns width unit from the surface-side to the bottom-side by Microscopic transmission-FTIR. The results showed that the concentration of PS was significantly greater in the vicinity of the surface of the film than that in the bulk, i.e., the component of PS enriched to the surface. Focusing the reflecting infrared light on different layer of the film, we can detect the composition of the different depth region in the PS/PMMA blend film. As the result, PMMA aggregated to the bottom of the film. It was considered that this effect was related to the different affinity and wetting prosperities of the blend component to the substrate or air.

[Synthesis and spectroscopic studies of the oxothio heteropolyanion of [PMo9V3O40]6-]

Some compounds were obtained through addition H2S to the heteropoly-compound (NH4)4H2[PMo9V3O40].10H2O in dimethyformamide. The FTIR spectrum and NIR FT-Raman spectrum of these compounds were investigated. The spectroscopic studies of the compound II showed that it is a oxothio heteropoly-compound.

Ultrastructural localization of gustducin immunoreactivity in microvilli of type II taste cells in the rat

Gustducin is a transducin-like G protein (guanine nucleotide-binding protein) that is expressed in taste bud cells. Gustducin is believed to be involved in bitter and possibly sweet taste transduction. In the present study, we demonstrate that a subset of type II cells displays immunoreactivity to antisera directed against gustducin in taste buds of rat circumvallate papilla. Immunogold particles are present both in the microvilli and cytoplasm of the immunoreactive cells. Quantitative analysis of the data suggests that the number of colloidal gold particles (P<0.001) and nanogold particles (P<0.01) in the immunoreactive type II cells are much greater than in type I cells. There are also approximately 2.5 times (P<0.05) as many colloidal gold particles associated with the microvilli versus the cytoplasm in the immunoreactive type II cells. The ultrastructural distribution of gustducin immunoreactivity is consistent with its proposed role in the initial events of sensory transduction by gustatory receptor cells.

Taste cells with synapses in rat circumvallate papillae display SNAP-25-like immunoreactivity

SNAP-25 is a 25 kDa protein believed to be involved in the processes of membrane fusion and exocytosis associated with neurotransmitter release. In the present study we present evidence that SNAP-25-like immunoreactivity can be used as a marker for taste cells with synapses in rat circumvallate papillae. SNAP-25 immunoreactivity is present in most intragemmal nerve processes and a small subset of taste cells. Intense immunoreactivity is associated with the nerve plexus located below the base of the taste bud. Of a total of 87 taste cells with synapses onto nerve processes, 80 of the presynaptic taste cells had SNAP-25 immunoreactivity. The association of SNAP-25 immunoreactivity with taste cells possessing synapses suggests that these cells may be gustatory receptor cells. Because this SNAP-25 antibody can label taste cells with synapses, it may also serve as a useful tool for future studies correlating structure with function in the taste bud.

[Determination of guanine plus cytosine content of Pseudomonas cocovenenans subsp farinofermantans with two methods and the comparative study]

The guanine plus cytosine content (G + C) mol% of Pseudomonas cocovenenans subsp farinofermantans, Burkholderia gladioli and Burkholderia cocovenenans, which were similar in biochemical characteristics, were determined with Tm values method and HPLC method, and the comparative study of these two methods was discussed. A negative conclusion could not be made from the results. The three bacteria were the same species. The HPLC method was more accurate than the Tm values method, but the repeatability of the latter was better.

Discrepancy between cytogenetic and FISH results on an amniotic fluid sample of 45,X/46,X,idic(Y)(p11)

The presence of abnormal ultrasound markers showing a thick nuchal fold with short middle phalanx of the fifth finger in an otherwise normal-appearing female fetus led to the sampling of amniotic fluid at 16 weeks gestation. Cytogenetic analysis with routine G-banding showed a 45,X karyotype in all 20 cells analysed from two flasks. However, fluorescent in situ hybridization on uncultured cells showed presence of a Y signal in 9 cells, 11 cells showing a single signal for the X. A cytogenetic analysis of the fetal blood at 23 weeks confirmed the presence of two cell lines, 45,X and 46,X, idic(Y)(p11). The couple opted to have the pregnancy terminated. However, the fetus was not available to carry out confirmatory tests.

Anticonvulsion effect of acupuncture might be related to the decrease of neuronal and inducible nitric oxide synthases

To measure the levels of hippocampal nitric oxide synthase isoforms in penicillin induced epilepsy and to test the effect of electroacupuncture (EA) on changes of these levels during epilepsy, we injected penicillin into rat hippocampus to make an epilepsy model and performed electroacupuncture treatment on "Feng Fu" (DU 16) and "Jin Suo" (DU 8) points in Wistar rats. Nitric oxide synthase (NOS) mRNA levels of rat hippocampus were determined by reverse transcription-polymerase chain reaction (RT-PCR). The neuronal nitric oxide synthase (nNOS) mRNA markedly increased (p<0.01) and inducible nitric oxide synthase (iNOS) mRNA significantly emerged during epilepsy, whereas no significant change in epithelial nitric oxide synthase (eNOS) mRNA was observed. EA inhibited the epilepsy and decreased nNOS (p<0.01) and iNOS (p<0.01) correspondingly but had no effect on the amount of eNOS mRNA. The data suggest that penicillin-induced epilepsy caused an increase in nNOS and iNOS, and the EA anticonvulsant effect might be related to the decrease of these nitric oxide synthases.

[The role of ozone solution on debridement and sterilization of burn wound]

OBJECTIVE

To observe the role of ozone solution on debridement and sterilization of burn wound.

METHODS

In vitro sterilizing effect on common isolated bacteria from burn wound and debridement and sterilization effects on burn wound of ozone disinfectant (ozone solution) were studied.

RESULTS

All the bacteria tested were killed in vitro by ozone solution. In addition, when ozone solution was applied on burn wound, its clearance rate of bacteria was 94.5% and the clinical effective rate was 97.1%.

CONCLUSION

Ozone is low in cost and high in effect which might be used as an agent for burn wound disinfection.

[Morphological changes of cultured rabbit retinal cells after injury]

PURPOSE

To investigate the morphological changes of cultured rabbit retinal cells after injury.

METHODS

Mechanical scratch was done in nenatol rabbit retinal cell culture and in Schwann Cell(SC)/retinal cell colculture. The morphological changes of different sorts of cells after the injury were observed under the phase contrast microscope for 24 h.

RESULTS

About 30 min after injury, many glial cells moved to the blank region and proliferated to form gliosis. Axons of retinal neurons began to regenerate 6 h post injury. The direction of regrowth was influenced by the environment. In the coculture, regeneration of axons was discerned only 3 h after injury.

CONCLUSION

Axons of retinal neurons had strong capability of regeneration; Gliosis was not the absolute obstacle of regeneration; SC played a role in promoting the axon regeneration.

The mechanism of nitric oxide and/or superoxide cytotoxicity in endothelial cells

We examined the mechanism of nitric oxide (NO) and/or superoxide (O2-)-induced cytotoxicity and the importance of thiols in endothelial cells by treating the cells with superoxide dismutase (SOD), catalase (CAT) and hemoglobin (Hb). Pyrogallol, a O2 generator and precursor of hydrogen peroxide (H2O2), had potent cytotoxic effects on the endothelial cells, but this effect was completely abolished by SOD/CAT. Hb, a NO scavenger, protected the endothelial cells from sodium nitroprusside-induced cytotoxicity. The cytotoxic effect of 3-morpholinosydnonimine (SIN-1), which is thought to form peroxynitrite (ONOO-) as a simultaneous O2- and NO generator, was completely blocked by SOD/CAT or Hb. On the other hand, pretreatment of endothelial cells with diethylmaleate, a glutathione depleter, aggravated the cytotoxicity induced by SIN-1, which was prevented by addition of exogenous glutathione and/or SOD/CAT. These data suggest that the cytotoxicity induced by NO, O2- and ONOO- can be blocked by glutathione, and that this is an important cellular protective mechanism against these reactive oxygen species.

[Effect of raw radish on pharmacological action of ginseng]

Ginseng decoction can increase the memory-improvement, weary-resistance, antihypoxia, sedation in mice, and increase the weight of spleen and accessory sexual gland, but reduce the weight of thymus. Raw radish can decrease these pharmacological effects in varying degrees, except the sedation.

[Zinc protective effects on pig retinal pigment epithelial cell damage of lipid peroxide induced by 2450 MHz microwave]

To observe the lipid peroxide damage in the cultured pig retinal pigment epithelial cell(RPE) induced by microwave and the protective effects by zinc (Zn). RPE cells were divided into 3 groups in terms of microwave intensity(the group of 10, 20 and 30 mW.cm-2) and each group was exposed to microwave for 1 hour. After adding ZnSO4 into DMEM culture fluid, the group of 30 mW.cm-2 was exposed to microwave. The activity of SOD and the content of MDA were measured. The results showed that the activity of SOD decreased significantly compared with the control group(P < 0.001). The content of MDA increased significantly compared with the control group(P < 0.001). Administration of Zn alleviated the increase of MDA and decrease of SOD. In the experiment, 2450 MHz microwave induces the lipid peroxide damage in RPE cells. Zn can enhance the antioxidation ability of cells and alleviate the damage to some extent.

Methylation of the cyclin A1 promoter correlates with gene silencing in somatic cell lines, while tissue-specific expression of cyclin A1 is methylation independent

Gene expression in mammalian organisms is regulated at multiple levels, including DNA accessibility for transcription factors and chromatin structure. Methylation of CpG dinucleotides is thought to be involved in imprinting and in the pathogenesis of cancer. However, the relevance of methylation for directing tissue-specific gene expression is highly controversial. The cyclin A1 gene is expressed in very few tissues, with high levels restricted to spermatogenesis and leukemic blasts. Here, we show that methylation of the CpG island of the human cyclin A1 promoter was correlated with nonexpression in cell lines, and the methyl-CpG binding protein MeCP2 suppressed transcription from the methylated cyclin A1 promoter. Repression could be relieved by trichostatin A. Silencing of a cyclin A1 promoter-enhanced green fluorescent protein (EGFP) transgene in stable transfected MG63 osteosarcoma cells was also closely associated with de novo promoter methylation. Cyclin A1 could be strongly induced in nonexpressing cell lines by trichostatin A but not by 5-aza-cytidine. The cyclin A1 promoter-EGFP construct directed tissue-specific expression in male germ cells of transgenic mice. Expression in the testes of these mice was independent of promoter methylation, and even strong promoter methylation did not suppress promoter activity. MeCP2 expression was notably absent in EGFP-expressing cells. Transcription from the transgenic cyclin A1 promoter was repressed in most organs outside the testis, even when the promoter was not methylated. These data show the association of methylation with silencing of the cyclin A1 gene in cancer cell lines. However, appropriate tissue-specific repression of the cyclin A1 promoter occurs independently of CpG methylation.

Application of cDNA microarrays in determining molecular phenotype in cardiac growth, development, and response to injury

BACKGROUND

Normal myocardial development and the tissue response to cardiac stress are accompanied by marked changes in gene expression; however, the extent of these changes and their significance remain to be fully explored. We used cDNA microarrays for gene expression profiling in rat cardiac tissue samples to study developmental transitions and the response to myocardial infarction (MI).

METHODS AND RESULTS

Microarrays with rat cDNAs for 86 known genes and 989 anonymous cDNAs obtained by molecular subtraction (representational difference analysis) of mRNA from sham-operated and 6-week post-MI samples were used in 2-color hybridization experiments. Twelve known genes previously associated with myocardial development were identified together with 10 uncharacterized expressed sequence tags and 36 genes not previously associated with cardiac development. After MI, genes associated with myocardial stress and wound healing exhibited differences in magnitude and expression kinetics, and 14 genes not previously associated with MI were identified. In situ hybridization revealed mRNA localization characteristic of wound healing and vascular and cardiomyocyte reactivity.

CONCLUSIONS

Tissue analysis of gene expression with cDNA microarrays provides a measure of transcriptional or posttranscriptional regulation and cellular recruitment. Our results demonstrate the complexity of gene regulation in the developing myocardium and show that cDNA microarrays can be used to monitor the evolution of the cardiac stress-inducible phenotype.

Differences in virulence between two Candida albicans strains in experimental keratitis

PURPOSE

To study the differences in disease caused by two wild-type strains of Candida albicans in a model of contact lens-facilitated keratitis in rabbits.

METHODS

Two strains, SC5314 and VE175, were examined. Standardized inocula were placed on the debrided corneal surface of one eye in Dutch belted rabbits and covered with a contact lens. A temporary tarsorrhaphy was opened after 24 hours with removal of the contact lens. Six days later, corneas were photographed and animals killed. Corneas were bisected with one half for quantitative isolate recovery and the other for stromal penetration by hyphae.

RESULTS

Strain SC5314 was significantly more virulent. The mean hyphal penetration into the cornea was 24.4% +/- 8.5% of the corneal thickness, and in three of six corneas hyphae penetrated through the entire cornea. In contrast, for VE175, the mean hyphal penetration was 2.6% +/- 1.2%. The difference between these two strains was statistically significant (P = 0.0297). Hyphae did not penetrate into the deep layers of the cornea in any of the six rabbits infected with VE175. The grading of clinical disease was consistent with histology, in that strain SC5314 caused more severe infection than VE175 and the difference was statistically significant (P = 0.0048). There was no difference in isolate recovery.

CONCLUSIONS

Wild-type strains of C. albicans can differ significantly in virulence as measured by depth of fungal invasion into corneas and clinical evaluation of infection. Further characterization of the intrinsic genetic differences between such strains may help identify factors responsible for fungal virulence.

[Epidemiological feature on diabetes mellitus among permanent inhabitant in the Special Economic Zone of Shenzhen]

OBJECTIVE

To investigate prevalence and relevant factors of diabetes mellitus among permanent inhabitant in Shenzhen.

METHODS

The prevalence of 8 200 inhabitants aged over 20 in Shenzhen was studied. Blood glucose was determined by glucose - oxidase method.

RESULTS

According to the WHO diagnostic standard, the prevalence rates of DM and IGT were 4.23% and 11.94% respectively. The prevalence increased apparently with age. The history of clan and overweight were related to the prevalence rates of DM and IGT. The people of DM and IGT were mostly accompanied with high levels of triglyceride, total cholesterol, uric acid, creatinine and low level of high dense lipoprotein (HDL).

CONCLUSION

The history of clan, old age, overweight and higher fattiness were found risk factors of DM and IGT.

Glucose limitation induces GCN4 translation by activation of Gcn2 protein kinase

Phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF-2alpha) is a well-characterized mechanism regulating protein synthesis in response to environmental stresses. In the yeast Saccharomyces cerevisiae, starvation for amino acids induces phosphorylation of eIF-2alpha by Gcn2 protein kinase, leading to elevated translation of GCN4, a transcriptional activator of more than 50 genes. Uncharged tRNA that accumulates during amino acid limitation is proposed to activate Gcn2p by associating with Gcn2p sequences homologous to histidyl-tRNA synthetase (HisRS) enzymes. Given that eIF-2alpha phosphorylation in mammals is induced in response to both carbohydrate and amino acid limitations, we addressed whether activation of Gcn2p in yeast is also controlled by different nutrient deprivations. We found that starvation for glucose induces Gcn2p phosphorylation of eIF-2alpha and stimulates GCN4 translation. Induction of eIF-2alpha phosphorylation by Gcn2p during glucose limitation requires the function of the HisRS-related domain but is largely independent of the ribosome binding sequences of Gcn2p. Furthermore, Gcn20p, a factor required for Gcn2 protein kinase stimulation of GCN4 expression in response to amino acid starvation, is not essential for GCN4 translational control in response to limitation for carbohydrates. These results indicate there are differences between the mechanisms regulating Gcn2p activity in response to amino acid and carbohydrate deficiency. Gcn2p induction of GCN4 translation during carbohydrate limitation enhances storage of amino acids in the vacuoles and facilitates entry into exponential growth during a shift from low-glucose to high-glucose medium. Gcn2p function also contributes to maintenance of glycogen levels during prolonged glucose starvation, suggesting a linkage between amino acid control and glycogen metabolism.

[A preliminary study of plasma oxidase activity by spectrophotometry on the healthy middle-aged and old volunteers in Changsha]

The plasma oxidase activities (POA) in 26 healthy volunteers were determined by spectrophotometry. The results showed that the POA value of the 26 cases was obviously lower (78.90 +/- 8.12 U.L-1) than that in Lasla's (84 +/- 5 U.L-1) (P < 0.05). A preliminary normal reference range of POA (45-60 years old) in Changsha was established. This method is an accurate (CV = 3.9%), cheaper, and easy one and applicable for clinical laboratories.

Relationship between toxicant transfer kinetic processes and fish oxygen consumption

Three organic compounds of different hydrophobicity, 1,2,4,5-tetrachlorobenzene (TeCB), 3,4,5,6-tetrachloroguaiacol (TeCG) and 4,6-dichlorobenzenediol (DBD), were chosen as the test chemicals to carry out a series of investigations to look at the relationship between toxicant transfer and fish metabolic rate. A significant correlation was found between the toxicant uptake rate constant (k(1)) and fish oxygen consumption, regardless of fish size and species. This correlation was improved when fish toxicant body load was expressed on a percent body lipid basis. Similarly, there also existed a significant relationship between the toxicant depuration rate constant (k(2)) and fish oxygen uptake for a range of chemicals with different octanol/water partition coefficients (K(ow)).

[Relationship between human herpesvirus 6 infection and idiopathic thrombocytopenic purpura]

OBJECTIVE

To investigate the pathogenic role of human herpesvirus 6 (HHV-6) in idiopathic thrombocytopenic purpura (ITP).

METHODS

HHV-6 DNA was examined by polymerase chain reaction (PCR) in bone marrow mononuclear cells (BMMNC) of 105 ITP patients. Human cytomegalovirus (HCMV) and parvovirus B(19) DNA were also examined in some cases. Platelet-associated antibodies (PAIg) were measured by competitive ELISA in 66 ITP patients. Serum IgG titer to HHV-6 was observed by indirect immunofluorescence assay in 19 ITP patients.

RESULTS

(1) HHV-6 DNA positivity was 41.0% for ITP patients, significantly higher than that for control group (P < 0.05). HHV-6 DNA positivity for adult ITP patients, especially adult chronic cases was significantly higher than that for childhood patients (P < 0.025). Positivities for parvovirus B(19) and HCMV DNA were 24.1% and 9.7%, respectively. (2) HHV-6 DNA positivity for patients with abnormal level of PAIgG was significantly higher than that for patients with normal level of PAIgG (P < 0.05). (3) Patients coinfected with HHV-6 and B(19) or HCMV had more severe symptoms or poorer prognosis.

CONCLUSION

HHV-6 infection might be associated with excessive PAIgG. Coinfection with HHV-6, B(19) or HCMV may cause more severe symptoms in ITP patients.

A physiological model to predict xenobiotic concentration in fish

A physiological model was developed to estimate fish body toxicant load based on information regarding the chemical exposure regime, fish body weight, lipid content and oxygen uptake. The general model was tested in which an oxygen database (OXYREF) was used to predict fish toxicant body burden. Based on the quantitative analysis, it was shown that the model was reliable and accurate in estimating fish body burden of a number of non-metabolized aquatic toxicants. This modified model possesses some functional reality which enables more realistic predictions, making it useful in the practice of aquatic environmental risk assessment.