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Biomedical subjects

Yan Li

Publications and source records attributed to Yan Li.

At least 433 records · Page 24Linked to original sources

[Protective effects of bicyclol on liver fibrosis induced by carbon tetrachloride].

OBJECTIVE: To study the protective effects and related mechanism of bicyclol on liver fibrosis induced by carbon tetrachloride (CCl(4)). METHODS: Forty male Wistar rats were injected subcutaneously with 25% CCl(4) twice a week for 3 months. Since the 7th week the rats were divided into 4 groups of 10 rats: normal control group, CCl(4) model group, bicyclol 100 mg/kg group (perfused of bicyclol into stomach 100 mg/kg qd for 45 days), and bicyclol 200 mg/kg group (perfused of bicyclol into stomach 200 mg/kg qd for 45 days). Twenty-four hours after the last administration the rats were killed. The serum was isolated to measure the levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), albumin/globulin (A/G), total protein (TP), hyaluronic acid (HA), and pro-collagen peptide III (PIIIP). Serum TNF alpha content was examined by ELISA assay, and liver TGF beta 1 level was determined by immunohistologic assay. The pathology of liver was examined. Twenty-eight mice were divided into 4 groups of 7 mice: normal control group, subacute group, 100 mg bicyclol group (perfused of bicyclol into stomach 50 mg/kg bid), and bicyclol 200 mg/kg group (perfused of bicyclol into stomach, 100 mg/kg bid), and 200 mg bicyclol group. Carbon tetrachloride was injected subcutaneously to the mice in the latter 3 groups every 3 days for 1 month. Twenty-four hours after the last administration the mice were killed and the serum was isolated to measure the levels of ALT, AST, TP, and albumin. Mitochondria were extracted from the livers of the experimental animals to measure the amount of protein. Mitochondrial glutathione (GSH) and malondialdehyde (MDA) contents were measured. The MDA and GSH contents in the control group were regarded as 100%, and the percentages of MDA and GSH in other groups were calculated. The fluidity of mitochondrial membrane and swelling degree of mitochondria were measured. Imunohistochemistry was used to detect the liver TGF beta 1. Nuclear NF kappa B DNA binding activity was investigated by electrophoretic mobility shift assay. RESULTS: Three months after the administration of carbon tetrachloride the serum ALT, AST, TB, HA, and PIIIP levels of the CCl(4) model group increased by 24, 10, 8, 28, and 4 times and the levels of albumin and A/G decreased significantly in comparison with those of the normal control group. However, the serum ALT, AST, TB, HA, and PIIIP levels in the 2 bicyclol groups were significantly lower than those in the model group. The pathological changes in the liver of the 2 bicyclol groups were significantly lighter than those in the model group. The serum TNF alpha increased significantly in the model group, however, the serum TNF alpha levels in the 2 bicyclol groups were significantly lower than that of the model group. The liver TGF beta 1 level in the model group was 4 times that of the normal control group. The liver TGF beta 1 level in the 2 bicyclol groups were significantly lower than that of the model group. One month after the administration of carbon tetrachloride to mice the serum ALT and AST increased and A/G decreased significantly. However, in the 2 bicyclol groups the serum ALT and AST were significantly lower and the A/G ratio was significantly higher in comparison with the model group. The mitochondrial GSH decreased by 34% and the mitochondrial MDA increased by 60% in the model group. The mitochondrial GSH was normal in the 2 bicyclol groups and the MDA level was significantly lower than that of the model group. The fluidity and swelling ability of mitochondrial membrane significantly decreased in the model group mice and the fluidity and swelling ability of mitochondrial membrane in the 2 bicyclol group mice were relatively normal. Twelve and twenty-four hours after the damage by carbon tetrachloride the binding activity of nuclear NF kappa B remained very high in the model group mice and was significantly lower in the 2 bicyclol group mice in comparison with the model mice. CONCLUSION: Bicyclol alleviates CCl(4)-induced liver fibrosis by its anti-peroxidation and anti-inflammation functions and regulation of NF-kappa B DNA-binding activity.

Animals↗

Association between the Ser128Arg variant of the E-selectin and risk of coronary artery disease in the central China.

BACKGROUND: The E-selectin mediates the interaction of activated endothelial cells with leukocytes and plays a fundamental role in the pathogenesis of coronary atherosclerosis. It has been suggested that a S/R (Ser128Arg) polymorphism of E-selectin might be associated with the predisposition to coronary artery disease (CAD). Our purpose was to determine whether this S/R polymorphism influences the risk of CAD in Chinese patients. METHODS AND RESULTS: We studied the human E-selectin gene polymorphism in a Chinese population by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). This polymorphism was determined in 248 CAD patients and in 256 control subjects. Frequencies of the SS, SR, and RR genotypes were found as 86.7%, 13.3%, and 0.0% in CAD patients and 93.8%, 6.2%, and 0.0% in control subjects, respectively. Frequency of the R allele was higher among CAD patients compared to controls(6.7% vs. 3.1%). However, either the genotype or the allele distribution of Ser128Arg polymorphism of E-selectin was statistically significantly different between the two groups (P<0.05). The odds ratio for the risk of CAD associated with the R allele was 2.21 (CI95%:1.20-4.07). CONCLUSIONS: These results suggest that the SR genotype of the E-selectin gene polymorphism in codon 128 is a genetic factor that may determine an individual's susceptibility for CAD in Chinese.

Alleles↗

Novel dry-desulfurization process using Ca(OH)2/fly ash sorbent in a circulating fluidized bed.

A dry-desulfurization process using Ca(OH)2/fly ash sorbent and a circulating fluidized bed (CFB) was developed. Its aim was to achieve high SO2 removal efficiency without humidification and production of CaSO4 as the main byproduct. The CaSO4 produced could be used to treat alkalized soil. An 83% SO2 removal rate was demonstrated, and a byproduct with a high CaSO4 content was produced through baghouse ash. These results indicated that this process could remove SO2 in flue gas with a high efficiency under dry conditions and simultaneously produce soil amendment. It was shown that NO and NO2 enhanced the SO2 removal rate markedly and that NO2 increased the amount of CaSO4 in the final product more than NO. These results confirmed that the significant effects of NO and NO2 on the SO2 removal rate were due to chain reactions that occurred under favorable conditions. The amount of baghouse ash produced increased as the reaction progressed, indicating that discharge of unreacted Ca(OH)2 from the reactor was suppressed. Hence, unreacted Ca(OH)2 had a long residence time in the CFB, resulting in a high SO2 removal rate. It was also found that 350 degrees C is the optimum reaction temperature for dry desulfurization in the range tested (320-380 degrees C).

Adsorption↗

A novel hIL-6 antagonist peptide from computer-aided design contributes to suppression of apoptosis in M1 cells.

Based on the complex crystal structure of human interleukin-6 (hIL-6) and its receptor (hIL-6R), a novel hIL-6 antagonist peptide (named PT) was designed using computer-guided design method. Dealing with molecular docking and molecular dynamics methods, the interaction between PT and hIL-6R was analyzed. The theoretical studies showed that PT possessed very high affinity to hIL-6R and offered a practical means of imposing long-term blockade of hIL-6 activity in vivo. This effect was examined due to growth arrest and apoptosis induced by hIL-6 in myeloblastic cell line M1 cells in a dose-dependent manner. The findings demonstrate that PT could also act as an excellent antagonist candidate for the induction of growth arrest and apoptosis. Furthermore, murine M1 myeloid cell line, which was induced by the physiological inducer hIL-6 to undergo apoptosis and growth arrest, could be used as a subtle model system to test hIL-6 antagonist.

Animals↗

Respiratory symptoms in relation to residential coal burning and environmental tobacco smoke among early adolescents in Wuhan, China: a cross-sectional study.

BACKGROUND: Cigarette smoking and coal burning are the primary sources of indoor air pollution in Chinese households. However, effects of these exposures on Chinese children's respiratory health are not well characterized. METHODS: Seventh grade students (N = 5051) from 22 randomly selected schools in the greater metropolitan area of Wuhan, China, completed an in-class self-administered questionnaire on their respiratory health and home environment. RESULTS: Coal burning for cooking and/or heating increased odds of wheezing with colds [odds ratio (OR) = 1.57, 95% confidence interval (CI): 1.07-2.29] and without colds (OR = 1.44, 95% CI: 1.05-1.97). For smoking in the home, the strongest associations were seen for cough (OR = 1.74, 95% CI: 1.17-2.60) and phlegm production (OR = 2.25, 95% CI: 1.36-3.72) without colds among children who lived with two or more smokers. CONCLUSIONS: Chinese children living with smokers or in coal-burning homes are at increased risk for respiratory impairment. While economic development in China may decrease coal burning by providing cleaner fuels for household energy use, the increasing prevalence of cigarette smoking is a growing public health concern due to its effects on children. Adverse effects of tobacco smoke exposure were seen despite the low rates of maternal smoking (3.6%) in this population.

Adolescent↗

Structure-based design and characterization of a Novel IL-6 antagonist peptide.

The development of rational methods to design antagonist peptides based on the 3-D structure of protein active region has, to now, been only marginally successful. This has been largely due to the difficulty of constraining the recognition elements of a mimetic structure to the relative conformational and spatial orientations present in the parent molecule. According to the 3-D complex structure of human interleukin-6 (hIL-6) and its receptor (hIL-6R), a novel antagonist peptide (named PT), which possessed potential bioactivity of hIL-6, was designed by the means of distance geometry, molecular modeling and molecular dynamics trajectory analysis. The bioactivity of the designed peptide (i.e. PT) was evaluated using XG-7 cells, a hIL-6-dependent B-cell line. PT possessed potential bioactivity to antagonize the function of hIL-6 and could efficiently induce the growth arrest and apoptosis of XG-7 cells in a dose-dependent manner.

Amino Acid Sequence↗

Exposure to hypomagnetic field space for multiple generations causes amnesia in Drosophila melanogaster.

This is the introduction of Drosophila into the study of learning and memory affected by removal of the geomagnetic field (GMF) for successive generations. Using the operant visual learning/memory paradigm at a flight simulator, the present study revealed that wild-type flies raised in a hypomagnetic field environment continuously for 10 successive generations were gradually impaired in visual conditioning learning and memory formation and finally the 10th generation flies became morphs of nonlearners and completely amnesiac. The control experiments show that the impairment could not be ascribed to any apparent sensorimotor problems in Drosophila. The reverse shift from hypomagnetic field (HMF) to natural GMF restored the GMF-free induced amnesia fully after six consecutive generations. Thus, our findings demonstrate conclusively that some serious, but reversible learning and memory impairment may occur for living organisms in a prolonged separation from GMF over many consecutive generations. And Drosophila has the potential to develop into a new model organism for the study of the neurobiology of magnetism for multiple generations.

Amnesia↗

Highly enantioselective cyanosilylation of aldehydes catalyzed by novel beta-amino alcohol-titanium complexes.

The beta-amino alcohol 1b-Ti(Oi-Pr)(4) complex has been shown to catalyze the enantioselective cyanosilylation of aldehydes efficiently. In the presence of 5 mol % of 1b-Ti(Oi-Pr)(4) complex catalyst, the aromatic, conjugated, heteroaromatic, and aliphatic aldehydes were converted to their corresponding trimethylsilyl ethers of cyanohydrins in 90-99% yields with up to 94% ee under mild conditions.

Journal Article↗

Polymorphisms in the MMP1 and MMP3 promoter and non-small cell lung carcinoma in North China.

Matrix metalloproteinases (MMPs) are proteolytic enzymes that regulate various cell behaviors in cancer biology, via their basic function of degradation of proteins. Genetic variations in several MMP promoters may influence transcription and expression of MMPs. The aim of this study is to assess the effects of the two single nucleotide polymorphisms (SNPs), the guanine insertion polymorphism in the MMP1 promoter and the adenosine insertion polymorphism in the MMP3 promoter, on risk of the development and lymphatic metastasis of non-small cell lung carcinoma (NSCLC). The MMP1 and MMP3 SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 243 NSCLC patients and 350 control subjects in North China. The overall genotype and allelotype distribution of both the variants in cancer patients and controls was not significantly different (all P values are above 0.05). However, stratification analysis showed that smoking individuals with the MMP3 5A allele had a >1.5-fold increased risk to develop NSCLC, compared with those harboring the 6A homozygous [the age and gender adjusted odds ratio (OR) = 1.68, 95% confidence interval (CI) = 1.04-2.70]. In addition, the frequency of the MMP3 5A homozygote in NSCLC patients with lymphatic metastasis was significantly higher than that in lymph node negative ones (5.7 versus 0%, P = 0.04). Moreover, the MMP 1G/5A haplotype significantly increased the risk of lymphatic metastasis (OR = 3.36, 95% CI = 1.42-7.94), compared with the 2G/6A haplotype. The present result suggested that the MMP3 promoter polymorphism may modify susceptibility to NSCLC, and the MMP 1G/5A haplotype may predicate the risk of lymphatic metastasis of this tumor.

Adult↗

Differential regulation of estrogen receptor (ER)alpha and ERbeta in primate mammary gland.

Estrogen, mainly estradiol (E2), and progesterone (P) are essential for the growth and differentiation of the breast, but their roles in breast cancer are highly debated. To understand how E2 and P influence cell proliferation and differentiation, it is essential to know how their receptors are regulated. Because of limited tissue availability, little is known about regulation of the two estrogen receptors (ERalpha and ERbeta) and the two progesterone receptor isoforms (PR-A and PR-B) in the normal human breast. What we know comes from rodent studies, which are not always pertinent for the human breast. We report now on regulation of gonadal hormone receptors during the menstrual cycle, pregnancy, and lactation in rhesus monkey mammary gland and on the relationship of these receptors to proliferation. We found that ERalpha but not ERbeta is down-regulated when E2 levels increase and when cells enter the cell cycle. PR-B but not PR-A is expressed in proliferating cells. Thus under normal conditions, the ratio of ERalpha to ERbeta in the breast depends on plasma concentrations of E2. Elevated expression of ERalpha (as occurs in postmenopausal women) is a normal response to loss of E2 and indicates nonproliferating cells. As selective receptor ligands become available, they will be helpful in delineation of the functions of these receptors.

Animals↗

17beta-hydroxysteroid dehydrogenase type 1 is an independent prognostic marker in breast cancer.

Estrogens have an important role in the development and progression of breast cancer. 17beta-Hydroxysteroid dehydrogenase type 1 (17HSD1), type 2 (17HSD2), and type 5 (17HSD5) are associated with sex steroid metabolism in normal and cancerous breast tissue. The mRNA expressions of the 17HSD1, 17HSD2, and 17HSD5 enzymes were analyzed in 794 breast carcinoma specimens by using tissue microarrays and normal histologic sections. The results were correlated with the estrogen receptor alpha (ER-alpha) and beta (ER-beta), progesterone receptor, Ki67, and c-erbB-2 expressions analyzed by immunohistochemical techniques and with the Tumor-Node-Metastasis classification, tumor grade, disease-free interval, and survival of the patients. Signals for 17HSD1 mRNA were detected in 16%, 17HSD2 in 25%, and 17HSD5 in 65% of the breast cancer specimens. No association between the 17HSD1, 17HSD2, and 17HSD5 expressions was detected. A significant association was observed between ER-alpha and ER-beta (P = 0.02; odds ratio, 1.96) expressions. There was also a significant inverse association between ER-alpha and 17HSD1 (P = 0.04; odds ratio, 0.53), as well as ER-alpha and 17HSD5 (P = 0.001; odds ratio, 0.35). Patients with tumors expressing 17HSD1 mRNA or protein had significantly shorter overall and disease-free survival than the other patients (P = 0.0010 and 0.0134, log rank). The expression of 17HSD5 was significantly higher in breast tumor specimens than in normal tissue (P = 0.033; odds ratio, 5.56). The group with 17HSD5 overexpression had a worse prognosis than the other patients (P = 0.0146). ER-alpha also associated with survival (P = 0.045). Cox multivariate analyses showed that 17HSD1 mRNA, tumor size, and ER-alpha had independent prognostic significance.

17-Hydroxysteroid Dehydrogenases↗

Basement membrane proteins play an active role in the invasive process of human hepatocellular carcinoma cells with high metastasis potential.

PURPOSE: Cell-matrix adhesive interaction has an important role in the invasive process of tumor cells, and integrins are the major receptors mediating cell-matrix adhesion. The current study is to investigate the modulation of basement membrane (BM) proteins, especially collagen IV (C IV), laminin (LN), and fibronectin (FN) in the invasive processes of human hepatocellular carcinoma (HCC) cells in vitro, and to reveal the roles of beta1 integrins and RGD-containing oligopeptide in the cell-matrix interaction. METHODS: Static adhesion assay was performed to study the rates of adhesion of MHCC97-H cells, treated or untreated with anti-beta1 (2 microg ml(-1)) and GRGDS, to C IV (50 microg ml(-1)), LN (50 microg ml(-1)) or FN (50 microg ml(-1)). Gelatin zymography was used to detect the secretion of MMPs in the conditioned medium of MHCC97-H cells incubated 24 h by C IV, LN or FN, and interactions with anti-beta1 and GRGDS. Transwell chamber assay was used to investigate the influence of C IV, LN or FN, interacting with anti-beta1 and GRGDS, on the cellular mobility of MHCC97-H cells. RESULTS: Compared with blank control group, MHCC97-H cells showed significantly higher rates of adhesion to C IV, LN, and FN. Pretreatment with anti-beta1 could suppress adhesion to C IV, LN or FN, but GRGDS inhibited adhesion to FN (P<0.05) only. LN and FN could stimulate the secretion of MMPs by MHCC97-H cells cultured in vitro, especially MMP-9 and its activated type. Treatment with anti-beta1 could partly counteract the effects of LN and FN. GRGDS could prominently induce the secretion of MMPs, but the effect could be inhibited by pretreatment of anti-beta1. The results of Transwell chamber assay showed that LN, FN, and GRGDS could increase the number of tumor cells penetrating the microporous membrane, but the data of C IV did not reach significance. The effects were partly counteracted by anti-beta1. CONCLUSION: BM proteins play an active role in the invasive process of human hepatocellular carcinoma cells. Integrin beta1 is an important molecule which mediates the cell-matrix adhesive interaction of tumor cells. RGD-containing peptides competitively combine with the binding site of integrin beta1, and the effects of FN are RGD sequence-dependent.

Basement Membrane↗

A novel TNFalpha antagonizing peptide-Fc fusion protein designed based on CDRs of TNFalpha neutralizing monoclonal antibody.

The variable regions of antibody molecules bind antigens with high affinity and specificity. The binding sites are imparted largely to the hypervariable portions (i.e., CDRs) of the variable region. Peptides derived from CDRs can bind antigen with similar specificity acting as mimic of antibody and become drug-designing core, although with markedly lower affinity. In order to increase the affinity and bioactivity, in this study, a novel peptide (PT) designed on CDRs of a TNFalpha neutralizing monoclonal antibody Z12 was linked with Fc fragment of human IgG1. The interaction mode of PT-linker-Fc (PLF) with TNFalpha was analyzed with computer-guided molecular modeling method. After expression in Escherichia coli and purification, recombinant PT-linker-Fc could bind directly with the TNFalpha coated on the ELISA plates. Furthermore, PLF could competitively inhibit the binding of Z12 to TNFalpha and also inhibit the TNFalpha-induced cytotoxicity on L929 cells. The TNFalpha antagonizing activity of PLF was significantly higher than that of the free peptide. This study highlights the potential of human Fc to enhance the potency of peptides designed on the CDRs of antibodies and could be useful in developing new TNFalpha antagonists.

Antibodies, Monoclonal↗

Renal function in relation to three candidate genes in a Chinese population.

We recently found in a white population that the genes encoding angiotensin-converting enzyme (ACE, I/D polymorphism), alpha-adducin (Gly460Trp), and aldosterone synthase (-344C/T) jointly influence renal function. We therefore investigated in a Chinese population the associations between the serum concentrations of creatinine and uric acid and these three genetic polymorphisms. We genotyped 471 ethnic Han Chinese subjects from 125 nuclear families recruited in northern China via random population sampling (75%) and at specialized hypertension clinics (25%). We performed population-based and family-based association analyses using generalized estimating equations (GEE) and quantitative transmission disequilibrium test (QTDT), respectively, while controlling for covariables. The participants were 39.7 years old and included 235 women (49.9%). The blood pressure measured at the subjects' homes averaged 126/80 mmHg. Mean values were 71 micromol/l for serum creatinine, 111 ml min(-1) 1.73 m(-2) for calculated creatinine clearance, and 236 micromol/l for serum uric acid. With adjustment for covariables, GEE analyses of single genes demonstrated that serum uric acid, but not serum creatinine, was positively associated with the ACE D allele. Serum uric acid concentrations were 15.8 micromol/l (95% confidence interval 3.3-28.2) and 25.7 micromol/l (11.1-40.2) higher in DD homozygotes than in ID and II subjects, respectively. Further GEE analyses of the three genes combined showed that the association between serum uric acid and the ACE polymorphism was confined to carriers of the alpha-adducin Gly and/or aldosterone synthase C alleles. Sensitivity analyses in parents and offspring separately as well as QTDT analyses were confirmatory. Among 114 informative offspring carrying the alpha-adducin Gly allele serum uric acid was significantly and positively associated with the transmission of the ACE D allele (beta=20.7 micromol/l). In conclusion, the present study extends our previous findings on the combined effects of the three candidate genes and supports the concept that these genetic polymorphisms jointly influence renal function.

Adult↗

Development and characterisation of neutralising monoclonal antibody to the SARS-coronavirus.

There is a global need to elucidate protective antigens expressed by the SARS-coronavirus (SARS-CoV). Monoclonal antibody reagents that recognise specific antigens on SARS-CoV are needed urgently. In this report, the development and immunochemical characterisation of a panel of murine monoclonal antibodies (mAbs) against the SARS-CoV is presented, based upon their specificity, binding requirements, and biological activity. Initial screening by ELISA, using highly purified virus as the coating antigen, resulted in the selection of 103 mAbs to the SARS virus. Subsequent screening steps reduced this panel to seventeen IgG mAbs. A single mAb, F26G15, is specific for the nucleoprotein as seen in Western immunoblot while five other mAbs react with the Spike protein. Two of these Spike-specific mAbs demonstrate the ability to neutralise SARS-CoV in vitro while another four Western immunoblot-negative mAbs also neutralise the virus. The utility of these mAbs for diagnostic development is demonstrated. Antibody from convalescent SARS patients, but not normal human serum, is also shown to specifically compete off binding of mAbs to whole SARS-CoV. These studies highlight the importance of using standardised assays and reagents. These mAbs will be useful for the development of diagnostic tests, studies of SARS-CoV pathogenesis and vaccine development.

Animals↗

[Clinical application of intro-aortic balloon pump and centrifugal pump in low cardiac output syndrome after coronary artery bypass grafting].

OBJECTIVE: To explore the clinical application of Intra-aortic balloon pump (IABP) and centrifugal pump in low cardiac output syndrome (LCOS) after coronary artery bypass grafting (CABG). METHODS: From April 2000 to January 2004, 5 patients suffered serious LCOS after CABG in our department. Because maximum vasoactive agent had no significant effect, we supported these 5 patients with IABP and centrifugal pumps. The centrifugal pumps were connected with cannulas of right superior pulmonary vein and ascending aorta. The flow rate of the centrifugal pumps were increased to 3-4 L/min gradually. The dosage of vasoactive agent and flow rate of the centrifugal pumps were decreased gradually after hemodynamics stabilized. RESULTS: All 5 patients' hemodynamics were improved significantly after the left ventricular assist by IABP and centrifugal pumps. Five patients were weaned from the centrifugal pumps after 4 to 7 days successfully. But some degree damage to blood cells and renal function were detected. Renal function of 3 patients were recovered gradually after centrifugal pumps removed and discharged successfully, One patient died of acute renal failure, 1 patient died of multiple organ failure, 5 patients need transfusion of whole blood or concentrated erythrocytes and 4 patients need transfusion of platelets. CONCLUSIONS: There were significant improvements in hemodynamics after support with IABP and centrifugal pumps in the patients who suffered serious LCOS with less effect of maximum vasoactive agent after CABG. Some complications on blood cells and renal function should be paid more attention.

Aged↗

The functional SNP in the matrix metalloproteinase-3 promoter modifies susceptibility and lymphatic metastasis in esophageal squamous cell carcinoma but not in gastric cardiac adenocarcinoma.

The matrix metalloproteinases (MMPs), a family of proteolytic enzymes that degrade different components of the extracellular matrix, play important roles in tumor development and invasion. A single adenine insertion/deletion polymorphism (6A/5A) in the MMP3 promoter region causes transcriptional elevation. The aim of this study was to assess the effects of this single nucleotide polymorphism (SNP) on the development and clinical staging of esophageal squamous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA). The MMP3 SNP was genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis in 417 cancer patients (234 ESCC and 183 GCA) and 350 controls in north China. The overall distribution of the MMP3 SNP in ESCC and GCA patients was not significantly different from that in healthy controls. However, smoking individuals with the 5A/5A or 5A/6A genotype were significantly more common in ESCC patients than in controls (37.5 versus 23.3%, xi(2) = 5.13, P = 0.02). Thus, smokers with at least one 5A allele had a significantly increased risk of ESCC, compared with 6A homozygotes (age and sex adjusted OR = 1.95, 95% CI = 1.08-3.53). The significant difference in the SNP distribution between ESCC patients, GCA patients and controls was not observed when stratified by family history of upper gastrointestinal cancer. In addition, the frequency of the 5A/5A + 5A/6A genotypes in ESCC patients with and without lymphatic metastasis was significantly different (45.8 versus 27.8%, xi(2) = 4.56, P = 0.03). Therefore, patients with at least one 5A allele were significantly more prone to lymphatic metastasis of ESCC. In contrast, no significant difference in the SNP distribution between patients with and without lymphatic metastasis was observed in GCA. The present study suggests that the MMP3 promoter SNP might be associated with a risk of development and lymphatic metastasis in ESCC but not in GCA.

Adenocarcinoma↗

Source identification of PM10, collected at a heavy-traffic roadside, by analyzing individual particles using synchrotron radiation.

Synchrotron radiation microbeam X-ray fluorescence (micro-SXRF) was used to analyze individual aerosol particles collected at a height of 2 m above a heavy-traffic roadside in a heavy-industrial area of Shanghai. A pattern recognition technique, which took micro-SXRF spectra of single aerosol particles as its fingerprint, was used to identify the origins of the particles. The particles collected from the environmental monitoring site are mainly from metallurgic industry (26%), unleaded gasoline automobile exhaust (15%), coal combustion (10%), cement dust (10%) and motorcycle exhaust (8%).

Aerosols↗