AIM:To investigate maspin expression in tumorigenesis and progression of gastric cancer and to explore its relevant molecular mechanisms.METHODS:Formalin-fixed and paraffin-embedded tissues from normal mucosa (n=182),...AIM:To investigate maspin expression in tumorigenesis and progression of gastric cancer and to explore its relevant molecular mechanisms.METHODS:Formalin-fixed and paraffin-embedded tissues from normal mucosa (n=182), dysplasia (n=69), cancer (n=l13) of the stomach were studied for maspin expression by immunohistochemistry. Microvessel density (MVD) in gastric cancer was labeled using anti-CD34 antibody. Maspin expression was compared with clinical parameters and MVD of tumors. Caspase-3 expression was also detected in gastric carcinoma by immunohistochemistry. The relationship between Caspase-3 and maspin expression was concerned as well.RESULTS:The positive rates of maspin expression were 79.8% (145/182), 75.4%(52/69) and 50.4%(57/113) in normal mucosa, dysplasia and cancer of the stomach,respectively.Cancer less frequently expressed maspin than normal mucosa and dysplasia (P<0.05).Maspin expression showed a significantly negative association with invasive depth, metastasis, Lauren's and Nakamura's classification (P<0.05),but not with tumor size, Borrmann's classification,growth pattern or TNIVl staging (P>0.05). The positive rate of Caspase-3 was significantly lower in gastric cancer than in normal gastric mucosa (P<0.05,32.7% vs 50.4%). It was noteworthy that maspin expression was negatively correlated with MVD, but positively correlated with expression of Caspase-3 in gastric cancer (P<0.05).CONCLUSION:Down-regulated maspin expression is a late molecular event in gastric carcinogenesis. Reduced expression of maspin contributes to progression of gastric cancer probably by inhibiting cell adhesion, enhandng cell mobility,decreasing cell apoptosis and facilitating angiogenesis.Additionally altered expression of maspin underlies the molecular mechanism of differentiation of gastric cancer and supports the different histogenetic pathways of intestinal and diffuse gastric cancers. Maspin expression can be considered as an effective and objective marker to reveal biological behaviors of gastric cancer.展开更多
AIM: TO investigate the resistance rate of Helicobacter pylori(H pylori) to clarithromycin, metronidazole, amoxicillin and tetracycline to guide clinical practice, and to study the mechanism of Hpylori resistant to cl...AIM: TO investigate the resistance rate of Helicobacter pylori(H pylori) to clarithromycin, metronidazole, amoxicillin and tetracycline to guide clinical practice, and to study the mechanism of Hpylori resistant to clarithromycin. METHODS: Thirty Hpyloristrains were isolated from the mucosa of peptic ulcer, gastric tumor and chronic gastritis patients, then the minimal inhibitory concentration (MIC) to clarithromycin, metronidazole, amoxicillin and tetracycline was evaluated by E-test method. The sequence analysis of PCR fragments was conducted in 23S rRNA gene of H pylori resistant to clarithromycin to get the resistance mechanism of the bacteria. RESULTS: Among 30 Hpyloristrains, 7 cases were resistant to clarithromycin, 12 to metronidazole, 2 to tetracycline and no strain was found to be resistant to amoxicillin. The resistance rates were 23.3%, 40%, 6.7% and 0%, respectively. Three new mutation points were found to be related to the clarithromycin resistance in Hpyloriisolates, which were G2224A, C2245T and T2289C. CONCLUSION: In northeast China, H pylori shows high resistance to metronidazole, while sensitive to amoxicillin. The mechanism of resistance to clarithromycin may be related to the mutation of G2224A, C2245T and T2289C in the 23S rRNA gene.展开更多
To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 （El9） isolates collected from an outbreak associated with hand, foot and mouth disease （HFMD） in Tai＇an city of Sha...To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 （El9） isolates collected from an outbreak associated with hand, foot and mouth disease （HFMD） in Tai＇an city of Shandong Province of China from July to September, 2003. Methods Thirty seven Echovirus 19 isolates were isolated from stool specimens and throat swabs collected during the outbreak, then major capsid （VP1） genomic sequence was determined, and phylogenetic tree was done based on the VP1 sequences among these 37 and other El9 viruses deposited in the Genbank. Also a representative strain named CHN-SD03-TN12 was selected for sequencing of 5′-untranslated regions （5′-UTR）. Results The identity rate was about 98.9%-100% among all these 37 El9 viruses. The genetic relationships between these 37 El9 isolates and other strains reported were also depicted. The identity rate was about 78.4%-78.9% compared with El9 reference strain Burke. The substitutions in the sequence of 5′-UTR resulted in changes in the conjectural properties of 5′-UTR of El9 viruses. Condusion The genetic features of El9 viruses isolated during the outbreak in Shandong Province in 2003 may be associated with a genetic and antigenic drift that changes the virulence of the Shandong isolates, but the molecular changes in Shandong El9 viruses contributing to their phenotype remain to be further illuminated. However, the sequences described in this paper substantiate the changes taken place in capsid VPI and 5′UTR regions. These substitutions may contribute to their tropism and virulence, and play a significant role in pathogenesis and clinical manifestations of the disease.展开更多
AIM:To investigate the association between single nucleotide polymorphism (SNP) in promoter of the DNA methyltrans-ferase 3B(DNMT3B) gene and risk for development and lymphatic metastasis of gastric cardiac adenocarci...AIM:To investigate the association between single nucleotide polymorphism (SNP) in promoter of the DNA methyltrans-ferase 3B(DNMT3B) gene and risk for development and lymphatic metastasis of gastric cardiac adenocarcinoma (GCA). METHODS: The hospital based case-control study included 212 GCA patients and 294 control subjects without overt cancer. The DNMT3B SNP was genotyped by PCR and restriction fragment length polymorphism (RFLP) analysis. RESULTS: The C/C genotype was not detected in both GCA patients and controls. In control subjects, the frequency of T/T and C/T genotypes was 94.9% and 5.1% respectively, and that of T and C alleles was 97.4% and 2.6%, respectively. The genotype and allelotype distribution in the GCA patients was not significantly different from that in controls (P=0.34 and 0.33, respectively). When stratified by smoking status and family history of upper gastrointestinal cancer, significant difference in the genotype distribution was not observed between GCA patients and controls. The distribution of DNMT3B genotypes in GCA patents with or without lymphatic metastasis did not show significant difference (P= 0.42). CONCLUSION: The distribution of DNMT3B SNP in North China is distinct from that in Caucasians. Although this SNP has been associated with susceptibility to lung, head, neck and breast cancer, it may not be used as a stratification marker to predict susceptibility and lymphatic metastasis of GCA, at least in the population of North China.展开更多
AIM: To investigate association of the 2Gor1Gsingle nudeotide polymorphism (SNP) in matrix metalloproteinase 1 (MMP1) promoter with susceptibility to esophageal squam-ous cell carcinoma (ESCC) and gastric cardiac aden...AIM: To investigate association of the 2Gor1Gsingle nudeotide polymorphism (SNP) in matrix metalloproteinase 1 (MMP1) promoter with susceptibility to esophageal squam-ous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA) in a population of North China. METHODS: MMP1 promoter SNP was genotyped by polymerase-chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 417 cancer patients (234 ESCC and 183 GCA) and 350 healthy controls. RESULTS: The genotype frequencies of the MMP1 promoter SNP in healthy controls were 55.4% (2G/2G), 30% (1G/2G) and 14.6% (1G/1G), respectively. The genotype and allelotype distribution in ESCC and GCA patients was not significantly different from that in healthy controls (all lvalues were above 0.05). Compared with the 1G/1Ggenotype, neither the 2G/2Gnor in combination with the 1G/2G genotype significantly modified the risk of developing ESCC and GCA, the adjusted odds ratio was 1.28 (95%CI = 0.78-2.09), 1.23 (95%CI = 0.38-2.05) in ESCC and 1.39 (95%CI = 0.80-2.41), 1.34 (95%CI = 0.74-2.40) in GCA, respectively. When stratified by smoking status and family history of upper gastrointestinal cancer, the 2G/2Ggenotype alone or in combination with the 1G/2G genotype also did not show any significant influence on the risk of ESCC and GCA development. In addition, influence of the MMP1 SNP on lymphatic metastasis in ESCC and GCA was also not obs-erved. CONCLUSION: The 2Gor 1GSNP in the MMP1 promoter might not modify the risk of ESCC and GCA development and might not be used as a stratification marker to predict the potential of lymphatic metastasis in these two tumor types.展开更多
Using laser scanning confocal microscopy, we have found that the in cells loaded with fluo-3/AM, highest intracellular Ca(2+) in the perinuclear region is associated with the Golgi apparatus. The spatiotemporal subcel...Using laser scanning confocal microscopy, we have found that the in cells loaded with fluo-3/AM, highest intracellular Ca(2+) in the perinuclear region is associated with the Golgi apparatus. The spatiotemporal subcellu lar distribution of Ca(2+) in living human fibroblasts exposing to calcium-free medium in response to agonists has been investigated. PDGF, which releases Ca(2+) from intracellular stores by inositol(1, 4, 5)-trisphosphate pathway,produced a biphasic transient rise in intracellular calcium.The initial rise was resulted from a direct release of calcium from the Golgi apparatus. Calcium could be also released from and reaccumulated into the Golgi apparatus by the stimulation of thapsigargin, an inhibitor of the Ca(2+) transport ATPase of intracellular calcium store. Permeablizing the plasma membrane by 10 μM digitonin resulted in the calcium release from the Golgi apparatus and depletion of the internal calcium store. These results suggest that the Golgi apparatus plays a role in Ca(2+) regulation in signal transduction.展开更多
AIM: To investigate the possible association of microsomal epoxide hydrolase ( mEH) Tyr113 His polymorphism with susceptibility to esophageal squamous cell carcinoma (ESCC) in a population of North China.METHODS: The ...AIM: To investigate the possible association of microsomal epoxide hydrolase ( mEH) Tyr113 His polymorphism with susceptibility to esophageal squamous cell carcinoma (ESCC) in a population of North China.METHODS: The mEH-Tyr113 His genotypes were determined by polymerase-chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 257 patients with esophageal squamous cell carcinoma (ESCC) and 252 healthy subjects as a control group.RESULTS: The frequencies for Tyr and His alleles were 44.2 %, 55.8 % in ESCC patients, and 44.0 % and 56.0 %in healthy subjects, respectively. No statistic difference in allele distribution was observed between ESCC patients and controls (x2=0.008, P=0.929). The overall genotype distribution difference was not observed between cancer cases and controls (x2=2.116, P=-0.347). Compared with Tyr/Tyr genotype, neither His/His genotype nor in combination with Tyr/His genotype significantly modified the risk of the development of ESCC, the adjusted odds ratio was 1.076 (95 % CI=0.850-1.361) and 0.756 (95 % CI=0.493-1.157),respectively. When stratified for sex, age, smoking status and family history of upper gastrointestinal cancer, His/His genotype alone or in combination with Tyr/His genotype also did not show any significant influence on the risk of developing ESCC.CONCLUSION: MEH Tyr113His polymorphism may not be used as a stratification marker in screening individuals at a high risk of ESCC.展开更多
The reverse martensitic transformation of TiNi shape memory alloy fibers embedded in a pure aluminum matrix was studied in this paper. Results showed that the phase composition of the TiNi alloy fibers prior to prestr...The reverse martensitic transformation of TiNi shape memory alloy fibers embedded in a pure aluminum matrix was studied in this paper. Results showed that the phase composition of the TiNi alloy fibers prior to prestraining at the room temperature had a significant influence on the differential scanning calorimetry (DSC) results of the composites. By a comparison to the high temperature X-ray diffraction (XRD) results, it was confirmed that the martensite was divided into two groups: the self-accommodating martensite (SAM) and the preferentially oriented martensite (POM). The evolving process of the separation of martensite was discussed.展开更多
Mouse thymic stromal cell line 4 (MTSC4) is one of the stromal cell lines established in our laboratory. While losing the characteristics of epithelial cells, they express some surface markers shared with thymic dendr...Mouse thymic stromal cell line 4 (MTSC4) is one of the stromal cell lines established in our laboratory. While losing the characteristics of epithelial cells, they express some surface markers shared with thymic dendritic cells (TDCs). To further study the biological functions of these cells, we compared the capability of MTSC4 with TDCs in the induction of thymocyte apoptosis, using thymic reaggregation culture system. Apoptosis of thymocytes induced by MTSC4 and TDCs was measured by Annexin V and PI staining and analyzed by flow cytometry. We found that MTSC4 selectively augmented the apoptosis of CD4^+8^+ (DP) thymocytes. This effect was Fas/FasL independent and could not be blocked by antibodies to MHC class Ⅰ and class Ⅱ molecules. In addition, MTSC4 enhanced the apoptosis of DP thymocytes from different strains of mice, which implies that MTSC4-induced thymocyte apoptosis is not mediated by the TCR recognition of self peptide/MHC molecules. In contrast to MTSC4, thymocyte apoptosis induced by TDCs was MHC-restricted. Thus, MHC-independent fashion of stromal-DP thymocyte interaction may be one of the ways to induce thymocyte apoptosis in thymus. Our study has also shown that the interaction of MTSC4 stromal cells and thymocytes is required for the induction of thymocyte apoptosis.展开更多
Objective To study the outcome of tension-free vaginal tape (TVT) for the treatment of stress urinary incontinence (SUI) in women with cystocele. Methods Forty-two patients with SUI confirmed by urodynamics underwent ...Objective To study the outcome of tension-free vaginal tape (TVT) for the treatment of stress urinary incontinence (SUI) in women with cystocele. Methods Forty-two patients with SUI confirmed by urodynamics underwent the TVT procedure under local anesthesia. A prolapse repair was done simultaneously. Results Mean TVT operation time was 26.29 minutes. Mean blood loss was 29.86 mL. Eighty-eight percent of the patients were able to micturate spontaneously within 12 hours and residual urine was less than 100 mL. And 12% of the patients had to use indwelling catheter for 3-11 days. Average hospital stay was 2.91 days. Eighty-eight percent of patients were discharged within 2 days. All patients were followed up (an average of 10.26 months). According to subjective and objective assessment of the outcome, 39 patients (93%) were cured, another 3 patients (7%) were significantly improved and none was failed. There were no major complications such as bladder injury occurred. Conclusion TVT procedure is a minimal invasive, effective, and safe surgery for treatment of SUI.展开更多
The continuum energy distributions of the luminous blue variables R127 and R110 in the outburst phase are fitted with a circumstellar envelope model. Both stars show two peaks in their continuum, one near 1250? and t...The continuum energy distributions of the luminous blue variables R127 and R110 in the outburst phase are fitted with a circumstellar envelope model. Both stars show two peaks in their continuum, one near 1250? and the other in the optical band. We suggest that their UV and optical fluxes may have different origins: the UV flux comes from the central star while the optical flux comes from an expanding circumstellar envelope. We construct a model for LBVs consisting of two LTE atmosphere models with different temperatures, and find it to be in agreement with the observed spectral energy distributions of R127 and R110. According to our numerical experiments, R127's continuum is composed of fluxes from a circumstellar envelope of T<SUB>eff</SUB> = 8000 K, R = 485R<SUB>⊙</SUB>, and log g = 1, and from a central star of T<SUB>eff</SUB> = 17?000 K, R = 135R<SUB>⊙</SUB>, and log g = 2.5 with a permeating factor f = 0.5; while R110's continuum can be fitted by a circumstellar envelope of T<SUB>eff</SUB> = 7000 K, R = 350R<SUB>⊙</SUB>, and log g = 0.5, and a central star of T<SUB>eff</SUB> = 25?000 K, R = 27R<SUB>⊙</SUB>, and log g = 3.0 with a permeating factor f = 0.65. Both models show that the non-spherically symmetric, optically thick regions are formed surrounding the central star in the outburst phase. The light of the central star is shielded by the circumstellar envelope so that the visual brightness increases with the decrease/increase of the temperature/radius of the optically thick regions.展开更多
Purpose:To investigate the role of vimentin gene in cataractogenesis.Methods:The12.7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs.841injected embryos were transferred...Purpose:To investigate the role of vimentin gene in cataractogenesis.Methods:The12.7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs.841injected embryos were transferred into oviducts of pseudopregnant recipient females.of which 12pregnant mice gave birth to 49offsping mice.The integration and expression of exogenous gene in the offsping were analysed by Southern and Northern blot byhridizations,In the human senile cataract,the lens vimentin gene was analyzed with the chicken vi-mentin gene probe.Results:It showed that four of F1offspring were transgenic mice in which the chicken vimenttin gene was integrated in their genomes.The transgenic band was12kb,similar to the12.7kb chicken vimentin fragment injected.One2kbvi-mentin mRNAwas visualized on E2 mouse lens blot.which revealed that the chicken vimentin gene was efficiently expressed in this transgenic mouse.In the humansenile cataract lens,12kb BamHI-restricted vimentin fragments displayed a stronger hybridization signal than that of the control lens in Southern blot anal-ysis,It implies that the Formation of human senile cataract may be associated with the amplification of vimentin gene.Conclusions:We have successfully developed four transgenic mice bearing chicken vimentin gene and having mRNA expression which can be used for further study.It is to be observed if the normal lens cell function is affected by the expressed product and cataract occurs in our transgenic mice.The cause of the gene ampli-fication in human ctaract remains for further investigation.Eye Science 1995;11:113-116.展开更多
Based on a dynamic model for turbulent convection, we investigate the effects of dissipation and anisotropy of the turbulence on the convective energy transport. We introduce two time scales to describe the dissipati...Based on a dynamic model for turbulent convection, we investigate the effects of dissipation and anisotropy of the turbulence on the convective energy transport. We introduce two time scales to describe the dissipation of the turbulence, and approximate the anisotropy of the turbulence by Rotta's proposal of 'return to isotropy'. The improved turbulence model results in an equation to determine the temperature gradient in the convection zone, which is of similar form as that of the MLT. We apply the improved MLT to solar models, and find that the increases of the anisotropy and decreases of the dissipation of the turbulence reduce the value of the convection parameter a, because these processes enhance the convective energy transfer rate. Compared with the observed solar p-mode frequencies, it is plausible that the dissipation of the turbulence in the solar convection zone should be fairly strong, while the degree of anisotropy of the turbulence plays a less significant role on the structure of the solar convection zone.展开更多
Wu Yuhong published an article on the animals issued to the 6-uz-ga institution and its two cooks, in addition to two articles on the Calendar starting from the Month of Akiti in Puzris-Dagan, in 1996, 2000 and 2002. ...Wu Yuhong published an article on the animals issued to the 6-uz-ga institution and its two cooks, in addition to two articles on the Calendar starting from the Month of Akiti in Puzris-Dagan, in 1996, 2000 and 2002. From 2006, more and more Puzris-Dagan texts have been available to us through BDTNS and CDLI online, and this situation urged us to revise and make a complete archive of the four pairs of cooks （muhaldim） working in the e-uz-ga dining hall,展开更多
We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an ext...We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an extra 29-nucleotide sequence located at the nucleotide positions between 27,863 and 27,864 (referred to the complete sequence of BJ01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream of the N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29, suggests a significant genetic event and differentiates it from the previously reported genotype, the dominant form among all sequenced SARS-CoV isolates. A 17-nt segment of this extra sequence is identical to a segment of the same size in two human mRNA sequences that may interfere with viral genome replication and transcription in the cytosol of the infected cells. It provides a new avenue for the exploration of the virus-host interaction in viral evolution, host pathogenesis, and vaccine development.展开更多
Beijing has been one of the epicenters attacked most severely by the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) since the first patient was diagnosed in one of the city's hospitals. We now...Beijing has been one of the epicenters attacked most severely by the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) since the first patient was diagnosed in one of the city's hospitals. We now report complete genome sequences of the BJ Group, including four isolates (Isolates BJ01, BJ02, BJ03, and BJ04) of the SARS-CoV.It is remarkable that all members of the BJ Group share a common haplotype, consisting of seven loci that differentiate the group from other isolates published to date. Among 42 substitutions uniquely identified from the BJ group, 32 are non-synonymous changes at the amino acid level. Rooted phylogenetic trees, proposed on the basis of haplotypes and other sequence variations of SARS-CoV isolates from Canada, USA, Singapore, and China, gave rise to different paradigms but positioned the BJ Group, together with the newly discovered GD01 (GD-Ins29) in the same clade, followed by the H-U Group (from Hong Kong to USA) and the H-T Group (from Hong Kong to Toronto), leaving the SP Group (Singapore) more distant. This result appears to suggest a possible transmission path from Guangdong to Beijing/Hong Kong, then to other countries and regions.展开更多
Annotation of the genome sequence of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) is indispensable to understand its evolution and pathogenesis. We have performed a full annotation of the SA...Annotation of the genome sequence of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) is indispensable to understand its evolution and pathogenesis. We have performed a full annotation of the SARS-CoV genome sequences by using annotation programs publicly available or developed by ourselves. Totally, 21 open reading frames (ORFs) of genes or putative uncharacterized proteins (PUPs) were predicted. Seven PUPs had not been reported previously, and two of them were predicted to contain transmembrane regions. Eight ORFs partially overlapped with or embedded into those of known genes, revealing that the SARS-CoV genome is a small and compact one with overlapped coding regions. The most striking discovery is that an ORF locates on the minus strand. We have also annotated non-coding regions and identified the transcription regulating sequences (TRS) in the intergenic regions. The analysis of TRS supports the minus strand extending transcription mechanism of coronavirus. The SNP analysis of different isolates reveals that mutations of the sequences do not affect the prediction results of ORFs.展开更多
Knowledge of the evolution of pathogens is of great medical and biological significance to the prevention, diagnosis, and therapy of infectious diseases. In order to understand the origin and evolution of the SARS-CoV...Knowledge of the evolution of pathogens is of great medical and biological significance to the prevention, diagnosis, and therapy of infectious diseases. In order to understand the origin and evolution of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus), we collected complete genome sequences of all viruses available in GenBank, and made comparative analyses with the SARS-CoV. Genomic signature analysis demonstrates that the coronaviruses all take the TGTT as their richest tetranucleotide except the SARS-CoV. A detailed analysis of the forty-two complete SARS-CoV genome sequences revealed the existence of two distinct genotypes, and showed that these isolates could be classified into four groups. Our manual analysis of the BLASTN results demonstrates that the HE (hemagglutinin-esterase) gene exists in the SARS-CoV, and many mutations made it unfamiliar to us.展开更多
In this paper, several kinds of multivalued logic for relational database and their developing process are presented on the basis of null value's semantics. A new 5 valued logic is led into relational database con...In this paper, several kinds of multivalued logic for relational database and their developing process are presented on the basis of null value's semantics. A new 5 valued logic is led into relational database containing null talue. The feasibility and necessity of using 5 valued logic are expounded. Comparative calculation and logical calculation under 5 valued logic are defined at the end of the paper.展开更多
文摘AIM:To investigate maspin expression in tumorigenesis and progression of gastric cancer and to explore its relevant molecular mechanisms.METHODS:Formalin-fixed and paraffin-embedded tissues from normal mucosa (n=182), dysplasia (n=69), cancer (n=l13) of the stomach were studied for maspin expression by immunohistochemistry. Microvessel density (MVD) in gastric cancer was labeled using anti-CD34 antibody. Maspin expression was compared with clinical parameters and MVD of tumors. Caspase-3 expression was also detected in gastric carcinoma by immunohistochemistry. The relationship between Caspase-3 and maspin expression was concerned as well.RESULTS:The positive rates of maspin expression were 79.8% (145/182), 75.4%(52/69) and 50.4%(57/113) in normal mucosa, dysplasia and cancer of the stomach,respectively.Cancer less frequently expressed maspin than normal mucosa and dysplasia (P<0.05).Maspin expression showed a significantly negative association with invasive depth, metastasis, Lauren's and Nakamura's classification (P<0.05),but not with tumor size, Borrmann's classification,growth pattern or TNIVl staging (P>0.05). The positive rate of Caspase-3 was significantly lower in gastric cancer than in normal gastric mucosa (P<0.05,32.7% vs 50.4%). It was noteworthy that maspin expression was negatively correlated with MVD, but positively correlated with expression of Caspase-3 in gastric cancer (P<0.05).CONCLUSION:Down-regulated maspin expression is a late molecular event in gastric carcinogenesis. Reduced expression of maspin contributes to progression of gastric cancer probably by inhibiting cell adhesion, enhandng cell mobility,decreasing cell apoptosis and facilitating angiogenesis.Additionally altered expression of maspin underlies the molecular mechanism of differentiation of gastric cancer and supports the different histogenetic pathways of intestinal and diffuse gastric cancers. Maspin expression can be considered as an effective and objective marker to reveal biological behaviors of gastric cancer.
文摘AIM: TO investigate the resistance rate of Helicobacter pylori(H pylori) to clarithromycin, metronidazole, amoxicillin and tetracycline to guide clinical practice, and to study the mechanism of Hpylori resistant to clarithromycin. METHODS: Thirty Hpyloristrains were isolated from the mucosa of peptic ulcer, gastric tumor and chronic gastritis patients, then the minimal inhibitory concentration (MIC) to clarithromycin, metronidazole, amoxicillin and tetracycline was evaluated by E-test method. The sequence analysis of PCR fragments was conducted in 23S rRNA gene of H pylori resistant to clarithromycin to get the resistance mechanism of the bacteria. RESULTS: Among 30 Hpyloristrains, 7 cases were resistant to clarithromycin, 12 to metronidazole, 2 to tetracycline and no strain was found to be resistant to amoxicillin. The resistance rates were 23.3%, 40%, 6.7% and 0%, respectively. Three new mutation points were found to be related to the clarithromycin resistance in Hpyloriisolates, which were G2224A, C2245T and T2289C. CONCLUSION: In northeast China, H pylori shows high resistance to metronidazole, while sensitive to amoxicillin. The mechanism of resistance to clarithromycin may be related to the mutation of G2224A, C2245T and T2289C in the 23S rRNA gene.
基金This work was supported by Chinese Center for Disease Control and Prevention and Ministry of Health,China.
文摘To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 （El9） isolates collected from an outbreak associated with hand, foot and mouth disease （HFMD） in Tai＇an city of Shandong Province of China from July to September, 2003. Methods Thirty seven Echovirus 19 isolates were isolated from stool specimens and throat swabs collected during the outbreak, then major capsid （VP1） genomic sequence was determined, and phylogenetic tree was done based on the VP1 sequences among these 37 and other El9 viruses deposited in the Genbank. Also a representative strain named CHN-SD03-TN12 was selected for sequencing of 5′-untranslated regions （5′-UTR）. Results The identity rate was about 98.9%-100% among all these 37 El9 viruses. The genetic relationships between these 37 El9 isolates and other strains reported were also depicted. The identity rate was about 78.4%-78.9% compared with El9 reference strain Burke. The substitutions in the sequence of 5′-UTR resulted in changes in the conjectural properties of 5′-UTR of El9 viruses. Condusion The genetic features of El9 viruses isolated during the outbreak in Shandong Province in 2003 may be associated with a genetic and antigenic drift that changes the virulence of the Shandong isolates, but the molecular changes in Shandong El9 viruses contributing to their phenotype remain to be further illuminated. However, the sequences described in this paper substantiate the changes taken place in capsid VPI and 5′UTR regions. These substitutions may contribute to their tropism and virulence, and play a significant role in pathogenesis and clinical manifestations of the disease.
基金Supported by the National Natural Science Foundation of China,No.30371591the Natural Science Foundation of Hebei Province,No.C20040062
文摘AIM:To investigate the association between single nucleotide polymorphism (SNP) in promoter of the DNA methyltrans-ferase 3B(DNMT3B) gene and risk for development and lymphatic metastasis of gastric cardiac adenocarcinoma (GCA). METHODS: The hospital based case-control study included 212 GCA patients and 294 control subjects without overt cancer. The DNMT3B SNP was genotyped by PCR and restriction fragment length polymorphism (RFLP) analysis. RESULTS: The C/C genotype was not detected in both GCA patients and controls. In control subjects, the frequency of T/T and C/T genotypes was 94.9% and 5.1% respectively, and that of T and C alleles was 97.4% and 2.6%, respectively. The genotype and allelotype distribution in the GCA patients was not significantly different from that in controls (P=0.34 and 0.33, respectively). When stratified by smoking status and family history of upper gastrointestinal cancer, significant difference in the genotype distribution was not observed between GCA patients and controls. The distribution of DNMT3B genotypes in GCA patents with or without lymphatic metastasis did not show significant difference (P= 0.42). CONCLUSION: The distribution of DNMT3B SNP in North China is distinct from that in Caucasians. Although this SNP has been associated with susceptibility to lung, head, neck and breast cancer, it may not be used as a stratification marker to predict susceptibility and lymphatic metastasis of GCA, at least in the population of North China.
基金Supported by the Grant from the Natural Science Foundation of China, No. 30371591Grant from Natural Science Foundation of Hebei Province, China, No. C200400062
文摘AIM: To investigate association of the 2Gor1Gsingle nudeotide polymorphism (SNP) in matrix metalloproteinase 1 (MMP1) promoter with susceptibility to esophageal squam-ous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA) in a population of North China. METHODS: MMP1 promoter SNP was genotyped by polymerase-chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 417 cancer patients (234 ESCC and 183 GCA) and 350 healthy controls. RESULTS: The genotype frequencies of the MMP1 promoter SNP in healthy controls were 55.4% (2G/2G), 30% (1G/2G) and 14.6% (1G/1G), respectively. The genotype and allelotype distribution in ESCC and GCA patients was not significantly different from that in healthy controls (all lvalues were above 0.05). Compared with the 1G/1Ggenotype, neither the 2G/2Gnor in combination with the 1G/2G genotype significantly modified the risk of developing ESCC and GCA, the adjusted odds ratio was 1.28 (95%CI = 0.78-2.09), 1.23 (95%CI = 0.38-2.05) in ESCC and 1.39 (95%CI = 0.80-2.41), 1.34 (95%CI = 0.74-2.40) in GCA, respectively. When stratified by smoking status and family history of upper gastrointestinal cancer, the 2G/2Ggenotype alone or in combination with the 1G/2G genotype also did not show any significant influence on the risk of ESCC and GCA development. In addition, influence of the MMP1 SNP on lymphatic metastasis in ESCC and GCA was also not obs-erved. CONCLUSION: The 2Gor 1GSNP in the MMP1 promoter might not modify the risk of ESCC and GCA development and might not be used as a stratification marker to predict the potential of lymphatic metastasis in these two tumor types.
文摘Using laser scanning confocal microscopy, we have found that the in cells loaded with fluo-3/AM, highest intracellular Ca(2+) in the perinuclear region is associated with the Golgi apparatus. The spatiotemporal subcellu lar distribution of Ca(2+) in living human fibroblasts exposing to calcium-free medium in response to agonists has been investigated. PDGF, which releases Ca(2+) from intracellular stores by inositol(1, 4, 5)-trisphosphate pathway,produced a biphasic transient rise in intracellular calcium.The initial rise was resulted from a direct release of calcium from the Golgi apparatus. Calcium could be also released from and reaccumulated into the Golgi apparatus by the stimulation of thapsigargin, an inhibitor of the Ca(2+) transport ATPase of intracellular calcium store. Permeablizing the plasma membrane by 10 μM digitonin resulted in the calcium release from the Golgi apparatus and depletion of the internal calcium store. These results suggest that the Golgi apparatus plays a role in Ca(2+) regulation in signal transduction.
基金the Scientific Grant of Educational Department of Hebei Province,China,No.2001150
文摘AIM: To investigate the possible association of microsomal epoxide hydrolase ( mEH) Tyr113 His polymorphism with susceptibility to esophageal squamous cell carcinoma (ESCC) in a population of North China.METHODS: The mEH-Tyr113 His genotypes were determined by polymerase-chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 257 patients with esophageal squamous cell carcinoma (ESCC) and 252 healthy subjects as a control group.RESULTS: The frequencies for Tyr and His alleles were 44.2 %, 55.8 % in ESCC patients, and 44.0 % and 56.0 %in healthy subjects, respectively. No statistic difference in allele distribution was observed between ESCC patients and controls (x2=0.008, P=0.929). The overall genotype distribution difference was not observed between cancer cases and controls (x2=2.116, P=-0.347). Compared with Tyr/Tyr genotype, neither His/His genotype nor in combination with Tyr/His genotype significantly modified the risk of the development of ESCC, the adjusted odds ratio was 1.076 (95 % CI=0.850-1.361) and 0.756 (95 % CI=0.493-1.157),respectively. When stratified for sex, age, smoking status and family history of upper gastrointestinal cancer, His/His genotype alone or in combination with Tyr/His genotype also did not show any significant influence on the risk of developing ESCC.CONCLUSION: MEH Tyr113His polymorphism may not be used as a stratification marker in screening individuals at a high risk of ESCC.
基金the National Natural Science Foundation of China under grant No. 59731030.
文摘The reverse martensitic transformation of TiNi shape memory alloy fibers embedded in a pure aluminum matrix was studied in this paper. Results showed that the phase composition of the TiNi alloy fibers prior to prestraining at the room temperature had a significant influence on the differential scanning calorimetry (DSC) results of the composites. By a comparison to the high temperature X-ray diffraction (XRD) results, it was confirmed that the martensite was divided into two groups: the self-accommodating martensite (SAM) and the preferentially oriented martensite (POM). The evolving process of the separation of martensite was discussed.
基金This work was funded by grants from Major State Bascic Research Development Program of China(No.G1999053904)National Natural Science Foundation of China(No.30271200)Young Scentist Cooperation Research Fund(No.39928019).
文摘Mouse thymic stromal cell line 4 (MTSC4) is one of the stromal cell lines established in our laboratory. While losing the characteristics of epithelial cells, they express some surface markers shared with thymic dendritic cells (TDCs). To further study the biological functions of these cells, we compared the capability of MTSC4 with TDCs in the induction of thymocyte apoptosis, using thymic reaggregation culture system. Apoptosis of thymocytes induced by MTSC4 and TDCs was measured by Annexin V and PI staining and analyzed by flow cytometry. We found that MTSC4 selectively augmented the apoptosis of CD4^+8^+ (DP) thymocytes. This effect was Fas/FasL independent and could not be blocked by antibodies to MHC class Ⅰ and class Ⅱ molecules. In addition, MTSC4 enhanced the apoptosis of DP thymocytes from different strains of mice, which implies that MTSC4-induced thymocyte apoptosis is not mediated by the TCR recognition of self peptide/MHC molecules. In contrast to MTSC4, thymocyte apoptosis induced by TDCs was MHC-restricted. Thus, MHC-independent fashion of stromal-DP thymocyte interaction may be one of the ways to induce thymocyte apoptosis in thymus. Our study has also shown that the interaction of MTSC4 stromal cells and thymocytes is required for the induction of thymocyte apoptosis.
文摘Objective To study the outcome of tension-free vaginal tape (TVT) for the treatment of stress urinary incontinence (SUI) in women with cystocele. Methods Forty-two patients with SUI confirmed by urodynamics underwent the TVT procedure under local anesthesia. A prolapse repair was done simultaneously. Results Mean TVT operation time was 26.29 minutes. Mean blood loss was 29.86 mL. Eighty-eight percent of the patients were able to micturate spontaneously within 12 hours and residual urine was less than 100 mL. And 12% of the patients had to use indwelling catheter for 3-11 days. Average hospital stay was 2.91 days. Eighty-eight percent of patients were discharged within 2 days. All patients were followed up (an average of 10.26 months). According to subjective and objective assessment of the outcome, 39 patients (93%) were cured, another 3 patients (7%) were significantly improved and none was failed. There were no major complications such as bladder injury occurred. Conclusion TVT procedure is a minimal invasive, effective, and safe surgery for treatment of SUI.
文摘The continuum energy distributions of the luminous blue variables R127 and R110 in the outburst phase are fitted with a circumstellar envelope model. Both stars show two peaks in their continuum, one near 1250? and the other in the optical band. We suggest that their UV and optical fluxes may have different origins: the UV flux comes from the central star while the optical flux comes from an expanding circumstellar envelope. We construct a model for LBVs consisting of two LTE atmosphere models with different temperatures, and find it to be in agreement with the observed spectral energy distributions of R127 and R110. According to our numerical experiments, R127's continuum is composed of fluxes from a circumstellar envelope of T<SUB>eff</SUB> = 8000 K, R = 485R<SUB>⊙</SUB>, and log g = 1, and from a central star of T<SUB>eff</SUB> = 17?000 K, R = 135R<SUB>⊙</SUB>, and log g = 2.5 with a permeating factor f = 0.5; while R110's continuum can be fitted by a circumstellar envelope of T<SUB>eff</SUB> = 7000 K, R = 350R<SUB>⊙</SUB>, and log g = 0.5, and a central star of T<SUB>eff</SUB> = 25?000 K, R = 27R<SUB>⊙</SUB>, and log g = 3.0 with a permeating factor f = 0.65. Both models show that the non-spherically symmetric, optically thick regions are formed surrounding the central star in the outburst phase. The light of the central star is shielded by the circumstellar envelope so that the visual brightness increases with the decrease/increase of the temperature/radius of the optically thick regions.
文摘Purpose:To investigate the role of vimentin gene in cataractogenesis.Methods:The12.7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs.841injected embryos were transferred into oviducts of pseudopregnant recipient females.of which 12pregnant mice gave birth to 49offsping mice.The integration and expression of exogenous gene in the offsping were analysed by Southern and Northern blot byhridizations,In the human senile cataract,the lens vimentin gene was analyzed with the chicken vi-mentin gene probe.Results:It showed that four of F1offspring were transgenic mice in which the chicken vimenttin gene was integrated in their genomes.The transgenic band was12kb,similar to the12.7kb chicken vimentin fragment injected.One2kbvi-mentin mRNAwas visualized on E2 mouse lens blot.which revealed that the chicken vimentin gene was efficiently expressed in this transgenic mouse.In the humansenile cataract lens,12kb BamHI-restricted vimentin fragments displayed a stronger hybridization signal than that of the control lens in Southern blot anal-ysis,It implies that the Formation of human senile cataract may be associated with the amplification of vimentin gene.Conclusions:We have successfully developed four transgenic mice bearing chicken vimentin gene and having mRNA expression which can be used for further study.It is to be observed if the normal lens cell function is affected by the expressed product and cataract occurs in our transgenic mice.The cause of the gene ampli-fication in human ctaract remains for further investigation.Eye Science 1995;11:113-116.
基金he NSFC under Grants 19625306 and19833040, and National Key Fundamental Research Project "Formation and Evolution of Galaxie
文摘Based on a dynamic model for turbulent convection, we investigate the effects of dissipation and anisotropy of the turbulence on the convective energy transport. We introduce two time scales to describe the dissipation of the turbulence, and approximate the anisotropy of the turbulence by Rotta's proposal of 'return to isotropy'. The improved turbulence model results in an equation to determine the temperature gradient in the convection zone, which is of similar form as that of the MLT. We apply the improved MLT to solar models, and find that the increases of the anisotropy and decreases of the dissipation of the turbulence reduce the value of the convection parameter a, because these processes enhance the convective energy transfer rate. Compared with the observed solar p-mode frequencies, it is plausible that the dissipation of the turbulence in the solar convection zone should be fairly strong, while the degree of anisotropy of the turbulence plays a less significant role on the structure of the solar convection zone.
基金supported by the Noble Group Fundthe W.F.Albright Institute of Archaeological ResearchJerusalem
文摘Wu Yuhong published an article on the animals issued to the 6-uz-ga institution and its two cooks, in addition to two articles on the Calendar starting from the Month of Akiti in Puzris-Dagan, in 1996, 2000 and 2002. From 2006, more and more Puzris-Dagan texts have been available to us through BDTNS and CDLI online, and this situation urged us to revise and make a complete archive of the four pairs of cooks （muhaldim） working in the e-uz-ga dining hall,
文摘We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an extra 29-nucleotide sequence located at the nucleotide positions between 27,863 and 27,864 (referred to the complete sequence of BJ01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream of the N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29, suggests a significant genetic event and differentiates it from the previously reported genotype, the dominant form among all sequenced SARS-CoV isolates. A 17-nt segment of this extra sequence is identical to a segment of the same size in two human mRNA sequences that may interfere with viral genome replication and transcription in the cytosol of the infected cells. It provides a new avenue for the exploration of the virus-host interaction in viral evolution, host pathogenesis, and vaccine development.
文摘Beijing has been one of the epicenters attacked most severely by the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) since the first patient was diagnosed in one of the city's hospitals. We now report complete genome sequences of the BJ Group, including four isolates (Isolates BJ01, BJ02, BJ03, and BJ04) of the SARS-CoV.It is remarkable that all members of the BJ Group share a common haplotype, consisting of seven loci that differentiate the group from other isolates published to date. Among 42 substitutions uniquely identified from the BJ group, 32 are non-synonymous changes at the amino acid level. Rooted phylogenetic trees, proposed on the basis of haplotypes and other sequence variations of SARS-CoV isolates from Canada, USA, Singapore, and China, gave rise to different paradigms but positioned the BJ Group, together with the newly discovered GD01 (GD-Ins29) in the same clade, followed by the H-U Group (from Hong Kong to USA) and the H-T Group (from Hong Kong to Toronto), leaving the SP Group (Singapore) more distant. This result appears to suggest a possible transmission path from Guangdong to Beijing/Hong Kong, then to other countries and regions.
文摘Annotation of the genome sequence of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) is indispensable to understand its evolution and pathogenesis. We have performed a full annotation of the SARS-CoV genome sequences by using annotation programs publicly available or developed by ourselves. Totally, 21 open reading frames (ORFs) of genes or putative uncharacterized proteins (PUPs) were predicted. Seven PUPs had not been reported previously, and two of them were predicted to contain transmembrane regions. Eight ORFs partially overlapped with or embedded into those of known genes, revealing that the SARS-CoV genome is a small and compact one with overlapped coding regions. The most striking discovery is that an ORF locates on the minus strand. We have also annotated non-coding regions and identified the transcription regulating sequences (TRS) in the intergenic regions. The analysis of TRS supports the minus strand extending transcription mechanism of coronavirus. The SNP analysis of different isolates reveals that mutations of the sequences do not affect the prediction results of ORFs.
文摘Knowledge of the evolution of pathogens is of great medical and biological significance to the prevention, diagnosis, and therapy of infectious diseases. In order to understand the origin and evolution of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus), we collected complete genome sequences of all viruses available in GenBank, and made comparative analyses with the SARS-CoV. Genomic signature analysis demonstrates that the coronaviruses all take the TGTT as their richest tetranucleotide except the SARS-CoV. A detailed analysis of the forty-two complete SARS-CoV genome sequences revealed the existence of two distinct genotypes, and showed that these isolates could be classified into four groups. Our manual analysis of the BLASTN results demonstrates that the HE (hemagglutinin-esterase) gene exists in the SARS-CoV, and many mutations made it unfamiliar to us.
文摘In this paper, several kinds of multivalued logic for relational database and their developing process are presented on the basis of null value's semantics. A new 5 valued logic is led into relational database containing null talue. The feasibility and necessity of using 5 valued logic are expounded. Comparative calculation and logical calculation under 5 valued logic are defined at the end of the paper.
