Wide-range amplified spontaneous emission wavelength tuning in a solid-state dye waveguide

Amplified spontaneous emission (ASE) in an organic-dye- (DCM-) doped poly(methyl methacrylate)/silica-gel hybrid material planar waveguide was investigated. ASE wavelength control and tuning in a wedge waveguide were realized. The tuning range of the waveguide can reach as much as 30 nm. This method can be applied to wide-range wavelength tuning in solid-state tunable lasers.

[Preparation of hepatitis C virus nonstructural region antigens and detection of their relative antibodies]

OBJECTIVE

To investigate the relationship between HCV NS3 and the pathogenesis of HCV and research a method to assess the therapeutic effect of interferon (lEN) in clinic.

METHODS

In a retrospective research, we used HCV-NS3 antigens of different terminals expressed in E. coli which contained the recombinant plasmids involving amino terminal region (N') or carboxyl terminal region (C') of HCV-NS3, to detect the antibodies by Western blot in sera of 63 hepatitis C patients who were treated with IFN.

RESULTS

It proved that antibodies against HCV-NS3 N' and/or HCV NS3 C' terminals in hepatitis C patients may predict the treatment result of IFN, especially in the patients with chronic hepatitis C.

CONCLUSIONS

The detection of antibodies against HCV-NS3 N' and/or C' terminals may be used for evaluation of IFN treatment, especially in chronic hepatitis C ones.

Gene content and organization of a 281-kbp contig from the genome of the extremely thermophilic archaeon, Sulfolobus solfataricus P2

The sequence of a 281-kbp contig from the crenarchaeote Sulfolobus solfataricus P2 was determined and analysed. Notable features in this region include 29 ribosomal protein genes, 12 tRNA genes (four of which contain archaeal-type introns), operons encoding enzymes of histidine biosynthesis, pyrimidine biosynthesis, and arginine biosynthesis, an ATPase operon, numerous genes for enzymes of lipopolysaccharide biosynthesis, and six insertion sequences. The content and organization of this contig are compared with sequences from crenarchaeotes, euryarchaeotes, bacteria, and eukaryotes.

[Tissue culture and rapid propagation of Aloe arborescens]

Tissue culture and rapid propagation of Aloe arborescens have been studied. The main results are as follows: the optimum medium for cluster shoots induction is MS + 6-BA 3.0 mg/L + NAA 0.2 mg/L; for cluster shoots propagation is MS + 6-BA 2.0 mg/L + NAA 0.2 mg/L; for roots induction is 1/2 MS + NAA 0.5 mg/L. The survival rate of the tube plantlets is 100% in the transplanting. Cutting down the cost of medium in large scale of production have been studied also.

Interaction of the poliovirus receptor with poliovirus

The structure of the extracellular, three-domain poliovirus receptor (CD155) complexed with poliovirus (serotype 1) has been determined to 22-A resolution by means of cryo-electron microscopy and three-dimensional image-reconstruction techniques. Density corresponding to the receptor was isolated in a difference electron density map and fitted with known structures, homologous to those of the three individual CD155 Ig-like domains. The fit was confirmed by the location of carbohydrate moieties in the CD155 glycoprotein, the conserved properties of elbow angles in the structures of cell surface molecules with Ig-like folds, and the concordance with prior results of CD155 and poliovirus mutagenesis. CD155 binds in the poliovirus "canyon" and has a footprint similar to that of the intercellular adhesion molecule-1 receptor on human rhinoviruses. However, the orientation of the long, slender CD155 molecule relative to the poliovirus surface is quite different from the orientation of intercellular adhesion molecule-1 on rhinoviruses. In addition, the residues that provide specificity of recognition differ for the two receptors. The principal feature of receptor binding common to these two picornaviruses is the site in the canyon at which binding occurs. This site may be a trigger for initiation of the subsequent uncoating step required for viral infection.

The ntrB and ntrC genes are involved in the regulation of poly-3-hydroxybutyrate biosynthesis by ammonia in Azospirillum brasilense Sp7

Azospirillum brasilense Sp7 and its ntrA (rpoN), ntrBC, and ntrC mutants have been evaluated for their capabilities of poly-3-hydroxybutyrate (PHB) accumulation in media with high and low ammonia concentrations. It was observed that the ntrBC and ntrC mutants can produce PHB in both low- and high-C/N-ratio media, while no significant PHB production was observed for the wild type or the ntrA mutant in low-C/N-ratio media. Further investigation by fermentation analysis indicated that the ntrBC and ntrC mutants were able to grow and accumulate PHB simultaneously in the presence of a high concentration of ammonia in the medium, while little PHB was produced in the wild type and ntrA (rpoN) mutant during active growth phase. These results provide the first genetic evidence that the ntrB and ntrC genes are involved in the regulation of PHB synthesis by ammonia in A. brasilense Sp7.

[The hydrogen bond between 5-(2-carboxyphenyl)-10, 15, 20-triphenylporphyrin and amino acid ester--study with UV-Vis titration and 1H-NMR]

The hydrogen bonds between the hydrogen of pyrrols in 5-(2-carboxyphenyl)-10,15,20-triphenylporphyrin and the oxygen of the carboxyl group of amino acid ester were confirmed by UV-Vis spectroscopic titration method and 1H-NMR. When amino acid ester was added to o-TPPCO2H solution in CHCl3, the Soret and Q and red-shifted dramatically and several isobestic points could be observed in UV-Vis spectra. In 1H-NMR, the signal of the hydrogen atoms of pyrrole in o-TPPCO2H (-2.78 ppm) decreased and a new signal in 0.260 ppm emerged, when o-TPPCO2H mixed with L-PheOEt at 1 : 1 (mol/mol).

[Changes and significance of natural killer cell, IL-2, IL-6 and TNF alpha of heroin addicts after detoxification]

In order to find out the activity of NKC and production of IL-2 in the peripheral blood mononuclear cells and the level of IL-6 and TNF alpha in the peripheral blood serum, we investigated 51 herion addicts who were in the course of detoxification. MTT colorimetric assay and ELISA assay methods were adopted. The results showed that, in the herion addicts, NK activity was 30.11 +/- 5.2%, IL-2 activity was 8.06 +/- 1.66 IU/ml, IL-6 level was 61.17 +/- 12.07 pg/ml, and TNF alpha level was 91.83 +/- 19.19 pg/ml, whereas in the healthy controls, the results were 44.89 +/- 4.75%, 15.91 +/- 3.83 IU/ml, 22.18 +/- 9.31 pg/ml and 30.55 +/- 11.94 pg/ml respectively. When the herion addicts were subjected to detoxication, their NKC and IL-2 activities, IL-6 and TNF alpha levels gradually restored to normal, and were correlated with the time of their detoxification (NKC: r = 0.626, P < 0.001; IL-2: r = 0.684, P < 0.001; IL-6: r = -0.791, P < 0.001; TNF alpha: r = -0.703, P < 0.001).

Involvement of DNA-dependent protein kinase in UV-induced replication arrest

Cells exposed to UV irradiation are predominantly arrested at S-phase as well as at the G(1)/S boundary while repair occurs. It is not known how UV irradiation induces S-phase arrest and yet permits DNA repair; however, UV-induced inhibition of replication is efficiently reversed by the addition of replication protein A (RPA), suggesting a role for RPA in this regulatory event. Here, we show evidence that DNA-dependent protein kinase (DNA-PK), plays a role in UV-induced replication arrest. DNA synthesis of M059K (DNA-PK catalytic subunit-positive (DNA-PKcs(+))), as measured by [(3)H]thymidine incorporation, was significantly arrested by 4 h following UV irradiation, whereas M059J (DNA-PKcs(-)) cells were much less affected. Similar results were obtained with the in vitro replication reactions where immediate replication arrest occurred in DNA-PKcs(+) cells following UV irradiation, and only a gradual decrease in replication activity was observed in DNA-PKcs(-) cells. Reversal of replication arrest was observed at 8 h following UV irradiation in DNA-PKcs(+) cells but not in DNA-PKcs(-) cells. Reversal of UV-induced replication arrest was also observed in vitro by the addition of a DNA-PK inhibitor, wortmannin, or by immunodepletion of DNA-PKcs, supporting a positive role for DNA-PK in damage-induced replication arrest. The RPA-containing fraction from UV-irradiated DNA-PKcs(+) cells poorly supported DNA replication, whereas the replication activity of the RPA-containing fraction from DNA-PKcs(-) cells was not affected by UV, suggesting that DNA-PKcs may be involved in UV-induced replication arrest through modulation of RPA activity. Together, our results strongly suggest a role for DNA-PK in S-phase (replication) arrest in response to UV irradiation.

[Effection of children airway foreign bodies on blood acid-base disturbances]

OBJECTIVE

To explore the effects of children airway foreign bodies on blood acid-base disturbances.

METHOD

To detect the blood-gas and electrolyte of 50 cases by children airway foreign bodies (test group), they were compared with 50 cases normal children (control group). To calculate anion gap (AG), to determine types of acidbase disturbances.

RESULT

The blood-gas and K+ were significant difference between that two groups. In the test group, there were 25 simple and 19 mixed acid-base disturbances; 6 acid-base balances. There were 31 high AG, 18 normal AG, one low AG.

CONCLUSION

Children airway foreign bodies can cause acid-base disturbances. It was major in simple metabolic acidosis and mixed metabolic acidosis with respiratory alkalosis, it was more in high AG-metabobic acidosis.

[Effects of nitric oxide on platelet function in burned rats]

OBJECTIVE

To investigate the effects of nitric oxide (NO) on rat platelet function after burn injury.

METHODS

Wistar rats with 30% TBSA full thickness burns were used as model, indices of platelet functions including platelet aggregation rate in first minute (PAR-1), maximal platelet aggregation rate (PAR-m), platelet dissipation rate (PDR) and platelet adhesion rate (PAR) were determined in four groups, namely burn control (B), NO donor (sin-1), NO synthesis inhibitor (L-NAME) and the normal control (C).

RESULTS

The PAR-1, PAR-m and PAR were significantly increased and the PDR was decreased remarkably after burn injury. In sin-1 group the PAR-1, PAR-m and PAR were obviously lower and the PDR was higher than that of B group (P < 0.05-0.01). In L-NAME group the PAR-1 was higher and the PDR was lower as compared with B group, but the PAR-m and PAR showed no significant differences between two groups.

CONCLUSIONS

The ability of platelet adhesion and aggregation induced by activated platelet are increased after burn injury. NO can partially reduce the degree of platelet activation and inhibit platelet aggregation. Moreover, it may dissipate aggregated platelets.

[Epidemiological survey on orchard pollinosis]

OBJECTIVE

To investigate the prevalence of Orchard Pollinosis in China.

METHOD

From 1995 to 1998, an epidemiological survey on orchard pollinosis was carried on among 1,660 primary and middle school students and 2,167 university students, including questionnaire investigation, nasal inspection and scratch test. From April to June of 1998, a clinical investigation of orchard pollinosis was adopted among 30 patients of allergic rhinitis including scratch test and nasal mucosa test.

RESULT

1. The total positive rate of orchard pollen scratch test was 6.7%, and the prevalence of orchard pollinosis was 0.37%. 2. 5 cases (16.7%) were hypersensitive to orchard pollen clinically in allergen test.

CONCLUSION

Orchard pollinosis is one kind of important pollinosis and should be paid high attention to.

[Isolation and sequencing of a novel form of cytochrome p-450 4F family from human liver]

OBJECTIVE

To isolate and sequence a novel gene of cytochrome p-450 4F family.

METHODS

A cDNA was isolated by touchdown PCR from a cDNA library of human fetal liver using specific primers. The DNA sequencing was done by an auto-sequence machine through forward and reverse directions. The expression of cDNA encoded protein was tested in yeast cells.

RESULTS

Sequencing of the full length cDNA revealed a sequence of 1,980 nucleotides coding for a protein of 520 amino acids with a molecular weight of 59,700 Da. The cDNA-deduced amino acid sequence showed 92% homology to that of human polymorphonuclear leukocytes (PMN) LTB4-hydroxylase (CYP4F3) and 91% homology to that of human liver LTB4 hydroxylase (CYP4F2). The expression of protein in the yeast cells showed a fusion protein with a molecular weight of about 86,000 Da and 60,000 Da after a proteolytic removal of the GST affinity tag. It was confirmed by RT-PCR that the gene was expressed in the adult liver.

CONCLUSION

Our results clearly show a novel form of cytochrome p-450 4F in human liver.

[Expression of multidrug resistance-associated protein in human non-small cell lung cancer]

OBJECTIVE

To investigate the expression of the multidrug resistance-associated protein(MRP) gene and MRP in human non-small-cell lung cancer tissues and to determine whether such expression was related to cell type, differentiation, tumour size, lymph node metastasis and prognosis.

METHODS

92 paraffin-embeded lung tumor samples (43 squamous cell carcinoma, 49 adenocarcinoma) and 16 fresh non-small-cell lung cancer samples were examined by using immunohistochemistry method and the reverse transcription-polymerase chain reaction (RT-PCR) technology respectively.

RESULTS

The expression of MRP mRNA and MRP were detectable in 31% (5-16) and 54% (50/92) of non-small-cell lung cancer specimens respectively. Eighteen(42%) squamous cell carcinoma specimens and thirty-two(65%) adenocarcinoma specimens showed positive immunostaining for MRP(P < 0.05). The expression of MRP was not related to tumour size, lymph node metastasis and cell differentiation significantly(P > 0.05). The five-year survival rate after operation of patients with MRP-positive tumours and MRP-negative tumours were 16% (8/50), 52% (22/42) respectively. Patients with MRP-positive tumours had shorter survival time than the MRP-negative patients significantly(P < 0.01).

CONCLUSIONS

Adenocarcinoma had higher MRP expression than squamous carcinoma significantly, positive MRP immunostaining appears to be an independent indicator of poor prognosis in NSCLC.

NBPA: a cerebral ischaemic protective agent

1. NBPA is a derivative of 3-n-butylpathalide isolated from Apium granolens Linn. 2. At concentrations ranging from 6 x 10(-6) to 10(-6) mol/L, NBPA inhibited the L-type calcium current in guinea-pig myocardial cells and cultured human neuroblastoma cells. 3. At 10(-6) mol/L, NBPA markedly inhibited calcium-dependent and -independent release of glutamate from synaptosomes. 4. The [31P] nuclear magnetic resonance spectrum has shown that pretreatment with NBPA at 15 mg/kg, i.p., improved energy metabolism. 5. In situ hybridization has shown that 10 and 20 mg/kg, i.p., NBPA prior to cerebral artery occlusion can accelerate the expression of heat shock protein 70 mRNA and inhibit c-fos mRNA expression. 6. It has been shown that NBPA decreases the nitric oxide content and bc nitric oxide synthase (NOS) activity in the global cerebral ischaemia-reperfusion model in rats. In addition, it has been shown that NBPA significantly inhibits the expression of inducible NOS protein.

Chinese traditional medicine and abnormal sex ratio at birth in China

A study of the abnormal sex ratio at birth in China reveals that it is not an entirely new phenomenon that emerged since the 1980s, but is simply more visible at present. Deliberate intervention to determine the sex of children has existed in the past few decades, at least in certain groups. Apart from modern medical methods, traditional Chinese medical practice is shown to be highly accurate in identifying the sex of a fetus. This may lead to sex-selective abortion and an abnormal sex ratio at birth. The possible causes of the abnormal sex ratio at birth include not only the real imbalance due to the disturbance of social factors, but also a spurious one attributable to the undercounting of female births. The real magnitude of the imbalance has been exaggerated by statistical error. The phenomenon is a complicated one reflecting the comprehensive socioeconomic setting. Among these factors, the stage of the fertility transition is one of the most decisive.

[The significance of TT virus detection in persons with elevated alanine aminotransferase during routine medical check up and patients with liver diseases]

OBJECTIVE

To investigate the significance of the new DNA virus (TTV) infection in persons with elevated alanine aminotransferase (ALT) during routine medical check up and patients with liver diseases, and analyze its pathogenesis.

METHODS

PCR was used in the detection of TTV DNA in 19 serum samples from ALT elevated persons and 41 from ALT normal persons during their routine medical check up, and 182 serum samples from patients with various kinds of liver diseases. PCR products were confirmed by RFLP. Other hepatitis viruses were simultaneously detected using routine methods.

RESULTS

TTV DNA was detected in 10.53% (2/19) and 2.44% (1/41) in groups of ALT elevated and control respectively with no significant difference between their detective rates (P > 0.05). There were 9 cases with current HBV infection, 1 case with hepatitis C and 1 case with hepatitis A in group of elevated ALT. Two TTV positive cases were both superinfected with HBV. The detecting rate of TTV DNA in patients with liver diseases was 4.4%. Only one case out of 18 non A to G hepatitis showed TTV DNA in serum.

CONCLUSION

There were TTV infections in Chinese population. The main cause for ALT elevation in persons during routine medical check up was HBV infection. There were TTV infections in patients with liver diseases too. However, TTV wasn't the main cause of non A to G hepatitis. Thus, the pathogenesis of TTV might be very weak.

[New method for the isolation of astroglial cells and oligodendrocytes]

Based on the different properties of cellular adhesions, developmental time-courses and growth pattern of astroglial cells and oligodendrocytes, a method of isolating glial cells in vitro was developed. The observations under inverted light microscope and scan electronic microscope identified that the morphology of isolated cells were consistent with the previous description. Immunocytochemical examination showed the expressions of markers, the glial fibrillary acidic protein (GFAP) of astroglia cells and the myelin basic protein (MBP) of oligodendrocytes were consistent with the isolated cells. All parameters showed that the isolated glial cells were pure, and the new methods were easy and reliable.

[A study on ovariectomized goat osteoblast culture in vitro]

Osteoblasts were isolated from the frontal parietal bone of ovariectomized goat and were confirmed by testing for multiple biological features. The results showed that the goat osteoblasts cultured had the typical morphological feature of osteoblasts, the activity of alkaline phosphatase, and the ability of calcification in vitro. Also, the results proved that these goat osteoblasts in vitro had the same function and features as those in vivo. The experimental techniques in this study have provided a useful system for researches in bone metabolism.

Protection of rabbits from viral challenge by gene gun-based intracutaneous vaccination with a combination of cottontail rabbit papillomavirus E1, E2, E6, and E7 genes

In this study, cottontail rabbit papillomavirus infection of domestic rabbits was used as an animal model to develop papillomavirus early gene-based vaccines. Groups of rabbits were intracutaneously vaccinated with single papillomavirus early genes E1, E2, E6, and E7 or with a combination of these four genes. Only a fraction of rabbits were protected from subsequent viral challenge when vaccinated with the E1 or E6 gene. Viral tumor growth in those rabbits vaccinated with the E1 or E2 gene was suppressed compared to that in controls. In contrast, seven of nine rabbits vaccinated with the combination of the E1, E2, E6, and E7 genes were completely protected against viral challenge. These data indicated that intracutaneous genetic vaccination with the combination of the E1, E2, E6, and E7 genes can be an effective strategy for immunoprophylaxis of papillomavirus infection.

[Antihypertensive study of xingnao qingxuan recipe]

OBJECTIVE

To observe the effect of decreasing blood pressure of Xingnao Qingxuan Casuples.

METHOD

The blood pressure in normal and anesthetised cats was examined with direct method, the blood pressure in the conscious SHR was obtained by indirect method.

RESULTS

Duodenuos administration(id) of XQC of 2.8 g/kg produced a decrease of blood pressure in normal cats; XQC of 1.4, 2.8 and 5.6 g/kg once a day for 14 days produced a dose-dependent reduction of blood pressure in SHR, 3-4 days after administration the blood pressure returned to the level before but the change was not significant. With gastric administration of XQC of 2.8 and 5.6 g/kg for 3 times, the incubation period of eyeball tremor induced by chloroform by dropping into the ear was prolonged by 14.4% and 13.0%, and the keeping time shortened by about 33.3% and 23.3% respectively. Brain basic arterial spasm induced by KCl or 5-HT in dog was relaxed obviously by XQC in vitro experiment.

CONCLUSION

XQC has the effect of reducing blood pressure resisting dizziness, which is related to the diastole of brain blood vessel.

[Intestinal blood perfusion improved by early enteral feeding in burned rat]

OBJECTIVE

To explore the mechanism of intestinal blood perfusion improved by early enteral feeding after burn injury.

METHODS

Wistar rats were inflicted with 30% total body surface area full thickness flame burn and randomly divided into three groups: burned control (B), burned and early feeding (EF), and normal control (C). The content of endothelin (ET), nitric oxide (NO), vasoactive intestinal peptide (VIP), and intestine mucosal blood flow (IMBF) were determined at postburn 0, 3, 6, 12, 24, 48 hours.

RESULTS

The content of ET, NO, VIP in small intestine as well as the ratio of ET/NO, ET/VIP were increased significantly and the IMBF was decreased markedly postburn. In EF group, ET, ET/NO and ET/VIP were significantly lower (P < 0.05, P < 0.01), and NO, VIP as well as IMBF were higher than those in B group (P < 0.05, P < 0.01). There were negative correlation between ET/NO, ET/VIP and IMBF (r(1) = -0.95, P < 0.01; r(2) = -0.87, P < 0.01).

CONCLUSIONS

The mechanism of intestinal blood perfusion improved by early enteral feeding may be correlated with increased NO, VIP and decreased ET induced by foods stimulating intestinal nerve.

Development of keratoacanthomas and squamous cell carcinomas in transgenic rabbits with targeted expression of EJras oncogene in epidermis

Activated ras genes have been frequently identified in both benign and malignant human tumors, including keratoacanthoma and squamous cell carcinoma. In this study, we developed two lines of transgenic rabbits in which the expression of EJras has been specifically targeted to the rabbit epidermal keratinocytes, using the upstream regulatory region of cottontail rabbit papillomavirus. All of the F1 transgenic progenies developed multiple keratoacanthomas at about 3 days after birth. The rabbits developed an average of 20 tumors, which usually reached the size of approximately 1 cm in diameter and then spontaneously regressed in about 2 months, similar to keratoacanthoma regression in humans. In addition, up to 18% of the rabbits then developed squamous cell carcinoma at about 5 months of age. The expression of EJras was detectable in all of the keratoacanthomas and squamous cell carcinomas. These results strongly support the involvement of the ras oncogene in both the initiation and regression of keratoacanthoma, and in the development of squamous cell carcinomas. These novel transgenic rabbits, with their consistent tumorigenic phenotype at an early age, high similarity to the human lesions, and easy accessibility for examination, manipulation, biopsy, and treatment, should provide a unique model system for studying ras activation-related tumor initiation, regression, and progression, and for evaluating antitumor therapies.

Growth factors and gene expression in cultured rat hepatocytes

BACKGROUND/AIM

The aim of this study was to evaluate the effect of replication on function variables in cultured hepatocytes.

METHODS

Isolated rat hepatocytes were cultured in HCM medium and plated on collagen-coated dishes at cell densities from 0.2 x 10(5) (subconfluent) to 1.0 x 10(5) x cm(-2) (confluent) with and without addition of hepatocyte growth factor, epidermal growth factor and insulin-like growth factor-I. The synthesis rate was measured for DNA, albumin, urea, and glucose together with mRNA levels (Northern blots) for albumin, urea cycle enzymes, and acute phase and "house-keeping" proteins.

RESULTS

In subconfluent culture the synthesis of DNA and urea was higher (118% and 112%, respectively), and of albumin and glucose lower (40% and 67%, respectively) than in confluent culture. The mRNA levels of carbamoylphosphate synthase, argininosuccinate synthetase, argininosuccinate lyase, arginase, a2-macroglobulin, beta-fibrinogen, and albumin were lower (23%, 58%, 77%, 33%, 12%, 50%, and 51%, respectively) in subconfluent culture compared with confluent culture. Relatively increased levels were found for beta-actin (109%) and alpha-tubulin (136%). In subconfluent culture hepatocyte growth factor increased the DNA synthesis rate 6-fold, epidermal growth factor 3-fold, and insulin-like growth factor-I 2-fold; that of albumin, urea and glucose was not increased significantly. In confluent culture the effect of growth factors on synthesis rates was not significant, and the growth factors had little influence on mRNA levels.

CONCLUSIONS

Hepatocytes produce urea at the same rate in subconfluent as in confluent culture in spite of a lower mRNA level of urea cycle enzymes. Hepatocyte growth factor and epidermal growth factor increase DNA synthesis markedly in subconfluent culture only, without significantly changing the ratio between subconfluent and confluent culture of other variables. This suggests that active replication is not an important cause of the relatively low liver-specific function of hepatocytes in subconfluent culture.