To explore the way to induce mesenchymal stem cells (MSCs) to differentiate into dopaminergic neurons in vitro. Methods MSCs were obtained from rat bone marrow, cultured and passaged. MSCs used in this experi...To explore the way to induce mesenchymal stem cells (MSCs) to differentiate into dopaminergic neurons in vitro. Methods MSCs were obtained from rat bone marrow, cultured and passaged. MSCs used in this experiment had multipotency, which was indirectly proved by being induced to differentiate into chondrocytes and adipocytes. MSCs were cultured in medium containing 0.5 mmol/L IBMX for 2 days. Then the medium was replaced with induction medium, which contained GDNF, IL-1β, mesencephalic glial-cell-conditioned medium and flash-frozen mesencephalic membrane fragments. The surface markers of the differentiated neurons, such as NSE, nestin, MAP-2a, b and TH were detected by immunocytochemistry and Western blot after MSCs were cultured in induction medium for 7 days and 15 days. Results MSCs differentiated into neural progenitors and expressed nestin after MSCs were incubated with medium containing IBMX for 2 d. After the medium was replaced with induction medium containing many inducing agents, MSCs differentiated into neuron-like cells and dopaminergic neuron-like cells and expressed NSE, MAP-2a, b and TH. The percentage of NSE-positive cells, MAP-2a, b-positive cells and TH-positive cells was 30.032±2.489%, 41.580±5.101% and 34.958±5.534%, respectively after MSCs were induced in medium containing GDNF, IL-1β, mesencephalic glial-cell-conditioned medium and flash-frozen mesencephalic membrane fragments for 15 days. Conclusion MSCs can differentiate into dopaminergic neuron-like cells and are a new cell source for the treatment of neurodegeneration diseases and have a great potential for wide application展开更多
Background Gene-radiotherapy, the combination of gene therapy and radiation therapy, is a new paradigm for cancer treatment. To enhance anti-tumor effect of gene-radiotherapy, in this study we construct a radiation-in...Background Gene-radiotherapy, the combination of gene therapy and radiation therapy, is a new paradigm for cancer treatment. To enhance anti-tumor effect of gene-radiotherapy, in this study we construct a radiation-inducible dual-gene co-expression vector pEgr-interferon(IFN)-γ- endostatin and studied the anti-tumor effect of pEgr-IFN-γ-endostatin gene-radiotherapy in mice bearing Lewis lung carcinoma and its mechanism.Methods Gene recombinant technique was used to construct dual-gene co-expression plasmid pEgr-IFN-γ-endostatin, and single-gene expression plasmid pEgr-IFN-γ and pEgr-endostatin. The plasmids packed by liposome were injected locally into the tumors of the mice, and the tumors were irradiated with 5 Gy X-ray 36 hours later. The tumor growth rate at different time and mean survival period of the mice were observed. Cytotoxic activity of splenic cytotoxic T-lymphocyte (CTL), natural killer (NK) cell and tumor necrosis factor (TNF)-α secretion activity of peritoneal macrophages of the mice in various groups were evaluated 15 days after irradiation. The intratumor micro-vessel density was evaluated by immunohistochemical staining 10 days after irradiation.Results The tumor growth rate of the mice in dual-gene-radiotherapy group was significantly lower than those in control group, 5 Gy group and single-gene-radiotherapy group at different time after gene-radiotherapy, and the mean survival period of which was longer. Cytotoxic activity of splenic CTL, NK and TNF-α secretion activity of peritoneal macrophages of the mice in dual-gene-radiotherapy group were significantly higher than those in control group, 5 Gy X-ray irradiation group and pEgr-endostatin gene-radiotherapy group 15 days after irradiation. The intratumor micro-vessel density of the mice in dual-gene-radiotherapy group was significantly lower than those in control group, 5 Gy X-ray irradiation group and pEgr-IFN-γgene-radiotherapy group. Conclusion The anti-tumor effect of dual-gene-radiotherapy was significantly better than that of s展开更多
To investigate the association between temperature and daily mortality in Shanghai from June 1, 2000 to December 31, 2001. Methods Time-series approach was used to estimate the effect of temperature on daily tota...To investigate the association between temperature and daily mortality in Shanghai from June 1, 2000 to December 31, 2001. Methods Time-series approach was used to estimate the effect of temperature on daily total and cause-specific mortality. We fitted generalized additive Poisson regression using non-parametric smooth functions to control for long-term time trend, season and other variables. We also controlled for day of the week. Results A gently sloping V-like relationship between total mortality and temperature was found, with an optimum temperature (e.g. temperature with lowest mortality risk) value of 26.7癈 in Shanghai. For temperatures above the optimum value, total mortality increased by 0.73% for each degree Celsius increase; while for temperature below the optimum value, total mortality decreased by 1.21% for each degree Celsius increase. Conclusions Our findings indicate that temperature has an effect on daily mortality in Shanghai, and the time-series approach is a useful tool for studying the temperature-mortality association.展开更多
AIM: To study the differential expression of proteins in normal and cancerous gastric tissues, and further identify new molecular markers for diagnosis and prognosis of gastric carcinoma, as well as develop new therap...AIM: To study the differential expression of proteins in normal and cancerous gastric tissues, and further identify new molecular markers for diagnosis and prognosis of gastric carcinoma, as well as develop new therapeutic targets of the disease.METHODS: Matched pairs of tissues from 6 gastric cancerpatients were analyzed for their two-dimensional electrophoresis (2DE) profiles. Soluble fraction proteins from human normal and cancerous gastric tissue were separated in the first dimension by isoelectric focusing on immobilized pH gradient (IPG, pH3-10) strips, and by125 g/L sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension with silver nitrate staining. Protein differential expression was analyzed by use of image analysis software to find out candidates for gastric cancer-associated proteins.RESULTS: Nine protein spots overexpressed in tumor tissues as compared with noncancerous regions. In the next step, 9 tumor-specific spots were cut off from Coomassie Brilliant Blue staining gels, digested in gel with L-l-tosylamide-2-phenylethyl chloromethyl ketone (TPCK)-trypsin. Protein identification was done by peptide mass fingerprinting with matrix assisted laser desorption/ionization-tirne of flight-mass spectrometry (MALDI-TOF-MS).In total, 5 tumor-specific protein spots corresponding to 5different polypeptide chains were identified, including annexin V, carbonic anhydrase, prohibitin, fibrin beta and fibrinogen fragment D. Among these 5 spots, the potential significance of the differential expressions is discussed.CONCLUSION Differential expression analysis of proteomes may be useful for the development of new molecular markers for diagnosis and prognosis of gastric carcinoma.展开更多
Our previous studies demonstrated that JWA, a novel retinoic acids responsive and cytoskeleton related gene, is associated with cell differentiation and apoptosis. In the present study, to elucidate if the JWA is a no...Our previous studies demonstrated that JWA, a novel retinoic acids responsive and cytoskeleton related gene, is associated with cell differentiation and apoptosis. In the present study, to elucidate if the JWA is a novel kind of microtubule-associated proteins (MAPs) and functionally link to microtubule, we first successfully identified JWA from the physically purified MAPs complex of rat brain tissues. The results of co-immunoprecipitation, gene trans-fection and immunofluorescence microscopy assays from HBE and NIH3T3 cells provide strong evidence for a linkage between JWA and b-tubulin. In general, JWA is stably binding to b-tubulin whenever microtubule is polymerized or not, and it may be critical to the mitosis process. In addi-tion, by use of the antisense oligonucleotides technique, we also showed that JWA is a negative modulator on intracellu-lar amino acids in PC12 cells. Further analysis indicated that JWA selectively regulates both taurine, an inhibitory amino acid, and glutamate, an excitatory amino acid. In conclusion, JWA is not only structurally associated, but also a novel functional MAP.展开更多
AIM: To study the application of artificial neural network (ANN) in forecasting the incidence of hepatitis A, which had an autoregression phenomenon.METHODS: The data of the incidence of hepatitis A in Liaoning Provin...AIM: To study the application of artificial neural network (ANN) in forecasting the incidence of hepatitis A, which had an autoregression phenomenon.METHODS: The data of the incidence of hepatitis A in Liaoning Province from 1981 to 2001 were obtained from Liaoning Disease Control and Prevention Center. We used the autoregressive integrated moving average (ARIMA) model of time series analysis to determine whether there was any autoregression phenomenon in the data. Then the data of the incidence were switched into [0,1] intervals as the network theoretical output. The data from 1981 to 1997 were used as the training and veriying sets and the data from 1998 to 2001 were made up into the test set.STATISTICA neural network (ST NN) was used to construct,train and simulate the artificial neural network.RESULTS: Twenty-four networks were tested and seven were retained. The best network we found had excellent performance, its regression ratio was 0.73, and its correlation was 0.69. There were 2 input variables in the network, one was AR(1), and the other was time. The number of units in hidden layer was 3. In ARIMA time series analysis results, the best model was first order autoregression without difference and smoothness. The total sum square error of the ANN model was 9 090.21, the sum square error of the training set and testing set was 8 377.52 and 712.69,respectively, they were all less than that of ARIMA model.The corresponding value of ARIMA was 12 291.79, 8 944.95 and 3 346.84, respectively. The correlation coefficient of nonlinear regression (RNL) of ANN was 0.71, while the RNL of ARIMA linear autoregression model was 0.66.CONCLUSION: ANN is superior to conventional methods in forecasting the incidence of hepatitis A which has an autoregression phenomenon.展开更多
AIM: To characterize the gene expression profiles in differentstages of carcinogenesis of esophageal epithelium.METHODS: A microarray containing 588 cancer relatedgenes was employed to study the gene expression profil...AIM: To characterize the gene expression profiles in differentstages of carcinogenesis of esophageal epithelium.METHODS: A microarray containing 588 cancer relatedgenes was employed to study the gene expression profileat different stages of esophageal squamous cell carcinomaincluding basal cell hyperplasia, high-grade dysplasia,carcinoma in situ, early and late cancer. Principle componentanalysis was performed to search the genes which wereimportant in carcinogenesis.RESULTS: More than 100 genes were up or down regulatedin esophageal epithelial cells during the stages of basal cellhyperplasia, high-grade dysplasia, carcinoma in situ, earlyand late cancer. Principle component analysis identified aset of genes which may play important roles in the tumordevelopment. Comparison of expression profiles betweenthese stages showed that some genes, such as P160ROCK,JNK2, were activated and may play an important role inearly stages of carcinogenesis. CONCLUSION: These findings provided an esophagealcancer-specific and stage-specific expression profiles,showing that complex alterations of gene expression underliethe development of malignant phenotype of esophagealcancer cells.展开更多
Objective Elevation of reactive oxygen species (ROS), especially the level of superoxide is a key event in many forms of cardiovascular diseases. To study the mechanism of tea polyphenols against cardiovascular diseas...Objective Elevation of reactive oxygen species (ROS), especially the level of superoxide is a key event in many forms of cardiovascular diseases. To study the mechanism of tea polyphenols against cardiovascular diseases, we observed the expressions of ROS-related enzymes in endothelial cells. Methods Tea polyphenols were co-incubated with bovine carotid artery endothelial cells (BCAECs) in vitro and intracellular NADPH oxidase subunits p22phox and p67phox, SOD-1, and catalase protein were detected using Western blot method. Results Tea polyphenols of 0.4 ug/mL and 4.0 ug/mL (from either green tea or black tea) down-regulated NADPH oxidase p22phox and p67phox expressions in a dose-negative manner (P<0.05), and up-regulated the expressions of catalase (P<0.05). Conclusions Tea polyphenols regulate the enzymes involved in ROS production and elimination in endothelial cells, and may be beneficial to the prevention of endothelial cell dysfunction and the development of cardiovascular diseases.展开更多
AIM: To explore the mode of inheritance of hepatocellular carcinoma (HCC) in a moderately high-incidence area of East China.METHODS: A pedigree survey was conducted in 210 families (3315 individuals) ascertained throu...AIM: To explore the mode of inheritance of hepatocellular carcinoma (HCC) in a moderately high-incidence area of East China.METHODS: A pedigree survey was conducted in 210 families (3315 individuals) ascertained through 210 HCC probands in Haimen, Jiangsu Province. Simple segregation analysis was conducted using SEGRANB software. The probability of ascertainment (π), segregation ratio (p), and the proportion of sporadic cases (x) were estimated. Complex segregation analysis was performed using the REGTL program of S.A.G.E.Models were fitted on the data of 3212 individuals that allowed for personal HBsAg status and variable age of onset in REGTL program.RESULTS: The estimate of segregation ratio was 0.191 by SEGRANB. The probability of ascertainment was 0.0266, and the proportion of sporadic cases was 0.465. The results of complex segregation analysis showed that Mendelian autosomal recessive inheritance of a major gene that influenced the age of onset distribution of HCC, provided the best fit to the data. In the best-fitting recessive model,the frequency of the disease allele was 0.11138. HBsAg seropositive status would significantly increase the risk of developing HCC.CONCLUSION: These results suggest that at least one major gene is involved in the genetic predisposition to develop HCC at an earlier age of onset. The seropositive HBsAg status can significantly increase the risk of developing HCC, which provides strong support for the interaction between genetic and environmental risk factors.展开更多
AIM: Inducible nitric oxide synthase (iNOS) plays a central role in the pathway of reactive oxygen and nitrogen species metabolism when Helicobacter pylori (H pylon) infection occurs in humans, iNOS Ser^608 Leu allele...AIM: Inducible nitric oxide synthase (iNOS) plays a central role in the pathway of reactive oxygen and nitrogen species metabolism when Helicobacter pylori (H pylon) infection occurs in humans, iNOS Ser^608 Leu allele, a novel genetic polymorphism (C/T) occurring within exon 16 of the iNOS reductase domain, may have a dramatic effect on the enzymatic activity. The aim of this study was to determine whether iNOS C/T polymorphism was associated with increased susceptibility to gastric cancer. METHODS: We conducted a population based case-control study in a high gastric cancer incidence area, Yangzhong, China. Questionnaires from 93 patients with intestinal type gastric cancer (IGC), 50 with gastric cardia cancer (GCC) and 246 healthy controls were obtained between 1997 and 1998, and iNOS genotyping was carried out. Odds ratios (ORs), interaction index (γ), and 95% confidence intervals for the combined effects of iNOS genotype and H pylori infection, cigarette smoking or alcohol drinking were estimated. RESULTS: The frequency of (CT+TT) genotypes was higher in cases than in control group (24.48% vs 23.17%), but the difference was not statistically significant. After adjusting for age and gender, past cigarette smokers with (CT+TT) genotypes had a significantly increased risk of IGC (OR=3.62, 95% CI:1.23-10.64), while past alcohol drinkers with (CT+TT) genotypes had a significantly increased risk of GCC (OR=3.33, 95% CI:1.14-9.67). H pylori CagA negative subjects with (CT+TT) genotypes had a significantly increased risk of both IGC and GCC (OR=2.19 and 3.52, respectively). CONCLUSION: iNOS Ser^608 Leu allele may be a potential determinant of susceptibility to cigarette -alcohol induced gastric cancer, but larger studies are needed to confirm the observations.展开更多
Objective To observe the effects of two main isoflavones, daidzein and genistein on the bone-nodule formation in rat calvaria osteoblasts in vitro. Methods Osteoblasts obtained from newborn Sprague-dawley rat calvaria...Objective To observe the effects of two main isoflavones, daidzein and genistein on the bone-nodule formation in rat calvaria osteoblasts in vitro. Methods Osteoblasts obtained from newborn Sprague-dawley rat calvarias were cultured for several generations. The second generation cells were cultured in Minimum Essential Medium supplemented with ascorbic acid and Na-beta-glycerophosphate for several days, in the presence of daidzein and genistein, with or without the estrogen receptor antagonist ICI 182780. Number of nodules was counted at the end of the incubation period (day 20) by staining with Alizarin Red S calcium stain. The release of osteocalcin, as a marker of osteoblast activity, was also determined on day 7 and day 12 during the incubation period. Results Compared with the control, the numbers of nodules were both increased by incubation with daidzein and genistein. 17β-estradiol was used as a positive control and proved to be a more effective inducer of the increase in bone-nodules formation than daidzein and genistein. The release of osteocalcin into culture media was also increased in the presence of daidzein and genistein, as well as 17β-estradiol on day 7 and day 12 (day 12 were higher). The estrogen receptor antagonist ICI 182780 completely blocked the genistein- and 17β-estradiol-induced increase of nodule numbers and osteocalcin release in osteoblasts. However, the effects induced by daidzein could not be inhibited by ICI 182780. Conclusion These findings suggest that geinistein can stimulate bone-nodule formation and increase the release of osteocalcin in rat osteoblasts. The effects, like those induced by 17β-estradiol, are mediated by the estrogen receptor dependent pathway. Daidzein also can stimulate bone-nodule formation and increase the release of osteocalcin in rat osteoblasts, but it is not, at least not merely, mediated by the estrogen receptor dependent pathway.展开更多
Tuberous sclerosis (TS) is an autosomal dominant disorder with a significantrange of clinical expressions. The involvement of vital organs, such as the brain, kidney, heart andlung is the main cause of death in patien...Tuberous sclerosis (TS) is an autosomal dominant disorder with a significantrange of clinical expressions. The involvement of vital organs, such as the brain, kidney, heart andlung is the main cause of death in patients with TS. The aim of this study is to summarize thecharateristic cutaneous features and common extracutaneous involvement of TS, which are helpful tothe early detection of visceral involvement. The analyzed clinical data from 78 patients with TSincluded those from detailed history, physical and dermatological examination, cranial computedtomography ( CT) and magnetic resonance imaging ( MRI) , abdominal ultrasonography, chestroentgenography, hand and foot X-ray and ophthalmologic examination. The skin, brain and kidney wereinvolved frequently in TS patients. Hypomelanotic macules were the most common and earliestcutaneous lesions. Their number was more than 3 in 81. 5% of'the patients. They were followed byfacial angiofibromas and Shangreen' s patch in a decreasing frequency. Forehead plaque, facialangiofibromas and Shagreen's patch appeared in patients at mean age of 2. 6, 6. 0 and 8. 1 yearsrespectively. Cranial CT showed a high positive rate in TS patients . Cutaneous features of TS arehelpful in the early diagnosis of the disease. Hypomelanotic macules are especially important forpatients with epilepsy or babies whose number of hypomelanotic malues is more than 3. Cranial CT isof great value in the diagnosis of TS. The involvement of visceral organs such as the brain andkidney should be examined in TS patients.展开更多
The in vitro inhibitory effect of trihydroxybenzoic acid dimer(TAD) extracted from Trapabispinosd roxb on HeLa cell growth was investigated via the MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diophenyl-tetrazolium bromide] r...The in vitro inhibitory effect of trihydroxybenzoic acid dimer(TAD) extracted from Trapabispinosd roxb on HeLa cell growth was investigated via the MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diophenyl-tetrazolium bromide] reduction method. The morphological changes of HeLa cells were observed by means of an optical microscope and a transmission electron microscope(TEM); the cell circles and apoptosis were detected by a flow cytometer. It was found that TAD can significantly inhibit the growth of Hela cells and can induce the apoptosis of HeLa cells. It was also found that the inhibition to the growth of Hela cells and the induction to the apoptosis of HeLa cells have a dosage-dependent feature. The inhibiting rates of TAD with mass concentrations of 25.000, 12.500 and 6.250 mg/L to the HeLa cell growth were 52.04%, 34.44% and 23.72% after 30 h, respectively, while those with TAD mass concentrations of 100.000, 50.000, 25.000, 12.500, 6.250 and 3.125 mg/L showed positive correlation with a correlation coefficient value of r=0.9859(P<0.01) and a IC_ 50 value of 10.90 mg/L. Observed by means of TEM, the HeLa cells exposed to 25.000, 12.500 and 6.250 mg/L TAD showed apoptosis to various extents, shrinkage of the cell nuclei, condensation and margination of chromatin, and cavitation of mitochondrion. An apoptosis peak was detected via a flow cytometer. It can be drawn from the results that TAD extracted from Trapabispinosd roxb has an evident inhibitory effect on the proliferation of and an inductive effect on the apoptosis of HeLa cells, but has no obvious arrest action towards the cell circles of HeLa cells.展开更多
Objective To investigate the relation of methionine synthase (MS) gene variation with congenital heart disease (CHD) phenotype. Methods One hundred and ninety three CHD patients (94 males and 99 females) and their bio...Objective To investigate the relation of methionine synthase (MS) gene variation with congenital heart disease (CHD) phenotype. Methods One hundred and ninety three CHD patients (94 males and 99 females) and their biological parents (nuclear families) in Liaoning Province were selected as the case group, and another 104 normal persons (60 males and 44 females) and their parents without family history of birth defects as the control group. For all subjects the polymorphism of MS gene A2756G locus was examined by PCR-RFLP method. Results In offspring of the control group the frequencies of MS genotype (+/ -) and allele (+) were 10.7% and 5.3%, without existence of homozygote. The MS genotype distribution and allele frequencies of CHD patients and their mothers were not significantly different from the control (P > 0.05). The frequency of allele (+) in case fathers (5.0 %) was apparently lower than that in the control (9.1%, P=0.060), and the odds ratio (OR) was 0.53 (95% CI: 0.25-1.09). There was no difference in parents' genotype combination between the two groups, and in genotype distribution among different types of CHD. Analysis of genetic transmission indicated that mutation allele (+) existed transmission disequilibrium in CHD nuclear families. The percentage of allele (+) transmitted from parents was lower than that allele (-) with OR 0.26 (95% CI: 0.11-0.60). Conclusion MS gene variation in parents is associated with occurrence of CHD in offspring, and mutation allele (+) in parents may be related with the decrease of CHD risk in offspring.展开更多
Objective To determine the best statistical distribution of concentration data of major air pollutants in Shanghai. Methods Four types of theoretic distributions (lognormal, gamma, Pearson V and extreme value) were...Objective To determine the best statistical distribution of concentration data of major air pollutants in Shanghai. Methods Four types of theoretic distributions (lognormal, gamma, Pearson V and extreme value) were chosen to fit daily average concentration data of PM10, SO2 and NO2 from June 1, 2000 to May 31, 2003 in Shanghai by using the maximum likelihood method. The fit results were evaluated by Chi-square test. Results The best-fit distributions for PM10,SO2 and NO2 concentrations in Shanghai were lognormal, Pearson V, and extreme value distributions, respectively. Conclusion The results can be further applied to local air pollution prediction and control, e.g., the probabilities exceeding the air quality standard and emission source reduction of air pollutant concentration to meet the standard.展开更多
Severe acute respiratory syndrome(SARS) is the first severe viral epidemic we encountered his century,which once spread in more than thirty countriesin2003.1 The etiological agent of SARS has beenc onfirmed to be a n...Severe acute respiratory syndrome(SARS) is the first severe viral epidemic we encountered his century,which once spread in more than thirty countriesin2003.1 The etiological agent of SARS has beenc onfirmed to be a novel coronavirus,namely SARS coronavirus(SARS-CoV),2,3 and the first outbreak of SARS has been successfully controlled world wide,but the identification of SARS-CoV isolated from wildanimals,the emergence of some sporadic SARS cases laterafter that outbreak,all suggest that the recurrence of such an epidemic is not unlikely in the future.In this case,development of SARS vaccines and specific drugs is undoubtedlyessential to the control and prevention from the possible outbreak.4,5展开更多
To investigate the relationship between G1958A gene polymorphism of methylenetetrahydrofolate dehydrogenase (MTHFD) and occurrence of congenital heart disease (CHD) in North China. Methods One hundred and ninety-two...To investigate the relationship between G1958A gene polymorphism of methylenetetrahydrofolate dehydrogenase (MTHFD) and occurrence of congenital heart disease (CHD) in North China. Methods One hundred and ninety-two CHD patients and their parents were included in this study as case group in Liaoning Province by birth defect registration cards, and 124 healthy subjects (age and gender matched) and their parents were simultaneously selected from the same geographic area as control. Their gene polymorphism of MTHFD G1958A locus was examined with PCR-RFLP, and serum folic acid and homocysteine (Hcy) levels were tested with radio-immunoassay and fluorescence polarization immunoassay (FPIA). Results There existed gene polymorphism at MTHFD G1958A locus in healthy subjects living in North China. The percentages of GG, GA, and AA genotype were 57.98%, 35.57%, and 6.45% respectively, and the A allele frequency was 24.23%, which was significantly different from Western population. No difference was observed when comparing genotype distribution and allele frequency between the case and control groups, so was the result from the comparison between genders. The A allele frequency of arterial septal defect patients’ mothers (10.87%) was significantly lower than that of controls (28.15%) (P=0.014), with OR=0.31 (95% CI: 0.09-0.84), and no difference in the other subgroups. The percentage of at least one parent carrying A allele in arterial septal defect subgroup (43.48%) was significantly lower than that in controls (69.64%) (P=0.017), with OR=0.34 (95% CI: 0.12-0.92). The analysis of genetic transmission indicated that there was no transmission disequillibrium in CHD nuclear families. Their serum folic acid level was significantly higher than that of controls (P=0.000), and Hcy level of the former was higher than that of the latter with no statistical significance (P>0.05). Serum Hcy and folic acid levels of mothers with gene mutation were lower than those of mothers with no mutation. Conclusion No 展开更多
Objective To obtain the exposure-response functions that could be used in health-based risk assessment of particulate air pollution in China. Methods Meta analysis was conducted on the literatures on air particulate m...Objective To obtain the exposure-response functions that could be used in health-based risk assessment of particulate air pollution in China. Methods Meta analysis was conducted on the literatures on air particulate matter and its adverse health outcomes in China and worldwide. Results For each health outcome from morbidity to mortality changes, the relative risks were estimated when the concentration of air particulate matter increased to some certain units. Conclusion The exposure-response functions recommended here can be further applied to health risk assessment of air particulate matter in China.展开更多
基金This work was supported by a grant from the National Natural Science Foundation of China (No.39970741) a grant from the the Scienceand Technology Foundation of Jilin Health Administration (No. 200131) and a grant from the Youth Teacher Foundation o
文摘To explore the way to induce mesenchymal stem cells (MSCs) to differentiate into dopaminergic neurons in vitro. Methods MSCs were obtained from rat bone marrow, cultured and passaged. MSCs used in this experiment had multipotency, which was indirectly proved by being induced to differentiate into chondrocytes and adipocytes. MSCs were cultured in medium containing 0.5 mmol/L IBMX for 2 days. Then the medium was replaced with induction medium, which contained GDNF, IL-1β, mesencephalic glial-cell-conditioned medium and flash-frozen mesencephalic membrane fragments. The surface markers of the differentiated neurons, such as NSE, nestin, MAP-2a, b and TH were detected by immunocytochemistry and Western blot after MSCs were cultured in induction medium for 7 days and 15 days. Results MSCs differentiated into neural progenitors and expressed nestin after MSCs were incubated with medium containing IBMX for 2 d. After the medium was replaced with induction medium containing many inducing agents, MSCs differentiated into neuron-like cells and dopaminergic neuron-like cells and expressed NSE, MAP-2a, b and TH. The percentage of NSE-positive cells, MAP-2a, b-positive cells and TH-positive cells was 30.032±2.489%, 41.580±5.101% and 34.958±5.534%, respectively after MSCs were induced in medium containing GDNF, IL-1β, mesencephalic glial-cell-conditioned medium and flash-frozen mesencephalic membrane fragments for 15 days. Conclusion MSCs can differentiate into dopaminergic neuron-like cells and are a new cell source for the treatment of neurodegeneration diseases and have a great potential for wide application
文摘Background Gene-radiotherapy, the combination of gene therapy and radiation therapy, is a new paradigm for cancer treatment. To enhance anti-tumor effect of gene-radiotherapy, in this study we construct a radiation-inducible dual-gene co-expression vector pEgr-interferon(IFN)-γ- endostatin and studied the anti-tumor effect of pEgr-IFN-γ-endostatin gene-radiotherapy in mice bearing Lewis lung carcinoma and its mechanism.Methods Gene recombinant technique was used to construct dual-gene co-expression plasmid pEgr-IFN-γ-endostatin, and single-gene expression plasmid pEgr-IFN-γ and pEgr-endostatin. The plasmids packed by liposome were injected locally into the tumors of the mice, and the tumors were irradiated with 5 Gy X-ray 36 hours later. The tumor growth rate at different time and mean survival period of the mice were observed. Cytotoxic activity of splenic cytotoxic T-lymphocyte (CTL), natural killer (NK) cell and tumor necrosis factor (TNF)-α secretion activity of peritoneal macrophages of the mice in various groups were evaluated 15 days after irradiation. The intratumor micro-vessel density was evaluated by immunohistochemical staining 10 days after irradiation.Results The tumor growth rate of the mice in dual-gene-radiotherapy group was significantly lower than those in control group, 5 Gy group and single-gene-radiotherapy group at different time after gene-radiotherapy, and the mean survival period of which was longer. Cytotoxic activity of splenic CTL, NK and TNF-α secretion activity of peritoneal macrophages of the mice in dual-gene-radiotherapy group were significantly higher than those in control group, 5 Gy X-ray irradiation group and pEgr-endostatin gene-radiotherapy group 15 days after irradiation. The intratumor micro-vessel density of the mice in dual-gene-radiotherapy group was significantly lower than those in control group, 5 Gy X-ray irradiation group and pEgr-IFN-γgene-radiotherapy group. Conclusion The anti-tumor effect of dual-gene-radiotherapy was significantly better than that of s
文摘To investigate the association between temperature and daily mortality in Shanghai from June 1, 2000 to December 31, 2001. Methods Time-series approach was used to estimate the effect of temperature on daily total and cause-specific mortality. We fitted generalized additive Poisson regression using non-parametric smooth functions to control for long-term time trend, season and other variables. We also controlled for day of the week. Results A gently sloping V-like relationship between total mortality and temperature was found, with an optimum temperature (e.g. temperature with lowest mortality risk) value of 26.7癈 in Shanghai. For temperatures above the optimum value, total mortality increased by 0.73% for each degree Celsius increase; while for temperature below the optimum value, total mortality decreased by 1.21% for each degree Celsius increase. Conclusions Our findings indicate that temperature has an effect on daily mortality in Shanghai, and the time-series approach is a useful tool for studying the temperature-mortality association.
基金Supported by the National Natural Science Foundation of China,No.30070671
文摘AIM: To study the differential expression of proteins in normal and cancerous gastric tissues, and further identify new molecular markers for diagnosis and prognosis of gastric carcinoma, as well as develop new therapeutic targets of the disease.METHODS: Matched pairs of tissues from 6 gastric cancerpatients were analyzed for their two-dimensional electrophoresis (2DE) profiles. Soluble fraction proteins from human normal and cancerous gastric tissue were separated in the first dimension by isoelectric focusing on immobilized pH gradient (IPG, pH3-10) strips, and by125 g/L sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension with silver nitrate staining. Protein differential expression was analyzed by use of image analysis software to find out candidates for gastric cancer-associated proteins.RESULTS: Nine protein spots overexpressed in tumor tissues as compared with noncancerous regions. In the next step, 9 tumor-specific spots were cut off from Coomassie Brilliant Blue staining gels, digested in gel with L-l-tosylamide-2-phenylethyl chloromethyl ketone (TPCK)-trypsin. Protein identification was done by peptide mass fingerprinting with matrix assisted laser desorption/ionization-tirne of flight-mass spectrometry (MALDI-TOF-MS).In total, 5 tumor-specific protein spots corresponding to 5different polypeptide chains were identified, including annexin V, carbonic anhydrase, prohibitin, fibrin beta and fibrinogen fragment D. Among these 5 spots, the potential significance of the differential expressions is discussed.CONCLUSION Differential expression analysis of proteomes may be useful for the development of new molecular markers for diagnosis and prognosis of gastric carcinoma.
基金supported by the National Natural Science Foundation of China(Grant Nos.30070664 and 30170812)the Foundation of High-Tech Key Project of Educational Department of Jiangsu Province(Grant No.JH01-049)+1 种基金the National Key Basic Research and Development Project(973)(Grant No.2002CB512905)the Project of the Ministry of Science and Technology of China(Grant Nos.2001-50 and 2000-026).
文摘Our previous studies demonstrated that JWA, a novel retinoic acids responsive and cytoskeleton related gene, is associated with cell differentiation and apoptosis. In the present study, to elucidate if the JWA is a novel kind of microtubule-associated proteins (MAPs) and functionally link to microtubule, we first successfully identified JWA from the physically purified MAPs complex of rat brain tissues. The results of co-immunoprecipitation, gene trans-fection and immunofluorescence microscopy assays from HBE and NIH3T3 cells provide strong evidence for a linkage between JWA and b-tubulin. In general, JWA is stably binding to b-tubulin whenever microtubule is polymerized or not, and it may be critical to the mitosis process. In addi-tion, by use of the antisense oligonucleotides technique, we also showed that JWA is a negative modulator on intracellu-lar amino acids in PC12 cells. Further analysis indicated that JWA selectively regulates both taurine, an inhibitory amino acid, and glutamate, an excitatory amino acid. In conclusion, JWA is not only structurally associated, but also a novel functional MAP.
基金Supported by the National Natural Science Foundation of China,No.30170833
文摘AIM: To study the application of artificial neural network (ANN) in forecasting the incidence of hepatitis A, which had an autoregression phenomenon.METHODS: The data of the incidence of hepatitis A in Liaoning Province from 1981 to 2001 were obtained from Liaoning Disease Control and Prevention Center. We used the autoregressive integrated moving average (ARIMA) model of time series analysis to determine whether there was any autoregression phenomenon in the data. Then the data of the incidence were switched into [0,1] intervals as the network theoretical output. The data from 1981 to 1997 were used as the training and veriying sets and the data from 1998 to 2001 were made up into the test set.STATISTICA neural network (ST NN) was used to construct,train and simulate the artificial neural network.RESULTS: Twenty-four networks were tested and seven were retained. The best network we found had excellent performance, its regression ratio was 0.73, and its correlation was 0.69. There were 2 input variables in the network, one was AR(1), and the other was time. The number of units in hidden layer was 3. In ARIMA time series analysis results, the best model was first order autoregression without difference and smoothness. The total sum square error of the ANN model was 9 090.21, the sum square error of the training set and testing set was 8 377.52 and 712.69,respectively, they were all less than that of ARIMA model.The corresponding value of ARIMA was 12 291.79, 8 944.95 and 3 346.84, respectively. The correlation coefficient of nonlinear regression (RNL) of ANN was 0.71, while the RNL of ARIMA linear autoregression model was 0.66.CONCLUSION: ANN is superior to conventional methods in forecasting the incidence of hepatitis A which has an autoregression phenomenon.
基金China Key Program on Basic Research,No.G1998051021the Chinese Hi-tech R&D program,No.2001AA231310National Natural Science Foundation of China,No.30170519
文摘AIM: To characterize the gene expression profiles in differentstages of carcinogenesis of esophageal epithelium.METHODS: A microarray containing 588 cancer relatedgenes was employed to study the gene expression profileat different stages of esophageal squamous cell carcinomaincluding basal cell hyperplasia, high-grade dysplasia,carcinoma in situ, early and late cancer. Principle componentanalysis was performed to search the genes which wereimportant in carcinogenesis.RESULTS: More than 100 genes were up or down regulatedin esophageal epithelial cells during the stages of basal cellhyperplasia, high-grade dysplasia, carcinoma in situ, earlyand late cancer. Principle component analysis identified aset of genes which may play important roles in the tumordevelopment. Comparison of expression profiles betweenthese stages showed that some genes, such as P160ROCK,JNK2, were activated and may play an important role inearly stages of carcinogenesis. CONCLUSION: These findings provided an esophagealcancer-specific and stage-specific expression profiles,showing that complex alterations of gene expression underliethe development of malignant phenotype of esophagealcancer cells.
基金This study was supported in part by the Japan-China Sasakawa Medical Fellowship.
文摘Objective Elevation of reactive oxygen species (ROS), especially the level of superoxide is a key event in many forms of cardiovascular diseases. To study the mechanism of tea polyphenols against cardiovascular diseases, we observed the expressions of ROS-related enzymes in endothelial cells. Methods Tea polyphenols were co-incubated with bovine carotid artery endothelial cells (BCAECs) in vitro and intracellular NADPH oxidase subunits p22phox and p67phox, SOD-1, and catalase protein were detected using Western blot method. Results Tea polyphenols of 0.4 ug/mL and 4.0 ug/mL (from either green tea or black tea) down-regulated NADPH oxidase p22phox and p67phox expressions in a dose-negative manner (P<0.05), and up-regulated the expressions of catalase (P<0.05). Conclusions Tea polyphenols regulate the enzymes involved in ROS production and elimination in endothelial cells, and may be beneficial to the prevention of endothelial cell dysfunction and the development of cardiovascular diseases.
基金the National Natural Science Foundation of China,No.39930160
文摘AIM: To explore the mode of inheritance of hepatocellular carcinoma (HCC) in a moderately high-incidence area of East China.METHODS: A pedigree survey was conducted in 210 families (3315 individuals) ascertained through 210 HCC probands in Haimen, Jiangsu Province. Simple segregation analysis was conducted using SEGRANB software. The probability of ascertainment (π), segregation ratio (p), and the proportion of sporadic cases (x) were estimated. Complex segregation analysis was performed using the REGTL program of S.A.G.E.Models were fitted on the data of 3212 individuals that allowed for personal HBsAg status and variable age of onset in REGTL program.RESULTS: The estimate of segregation ratio was 0.191 by SEGRANB. The probability of ascertainment was 0.0266, and the proportion of sporadic cases was 0.465. The results of complex segregation analysis showed that Mendelian autosomal recessive inheritance of a major gene that influenced the age of onset distribution of HCC, provided the best fit to the data. In the best-fitting recessive model,the frequency of the disease allele was 0.11138. HBsAg seropositive status would significantly increase the risk of developing HCC.CONCLUSION: These results suggest that at least one major gene is involved in the genetic predisposition to develop HCC at an earlier age of onset. The seropositive HBsAg status can significantly increase the risk of developing HCC, which provides strong support for the interaction between genetic and environmental risk factors.
基金Supported by Grants From the National Natural Science Foundation of China (30170827 to Jing.Shen and 30070671 to Run-Tian Wang)
文摘AIM: Inducible nitric oxide synthase (iNOS) plays a central role in the pathway of reactive oxygen and nitrogen species metabolism when Helicobacter pylori (H pylon) infection occurs in humans, iNOS Ser^608 Leu allele, a novel genetic polymorphism (C/T) occurring within exon 16 of the iNOS reductase domain, may have a dramatic effect on the enzymatic activity. The aim of this study was to determine whether iNOS C/T polymorphism was associated with increased susceptibility to gastric cancer. METHODS: We conducted a population based case-control study in a high gastric cancer incidence area, Yangzhong, China. Questionnaires from 93 patients with intestinal type gastric cancer (IGC), 50 with gastric cardia cancer (GCC) and 246 healthy controls were obtained between 1997 and 1998, and iNOS genotyping was carried out. Odds ratios (ORs), interaction index (γ), and 95% confidence intervals for the combined effects of iNOS genotype and H pylori infection, cigarette smoking or alcohol drinking were estimated. RESULTS: The frequency of (CT+TT) genotypes was higher in cases than in control group (24.48% vs 23.17%), but the difference was not statistically significant. After adjusting for age and gender, past cigarette smokers with (CT+TT) genotypes had a significantly increased risk of IGC (OR=3.62, 95% CI:1.23-10.64), while past alcohol drinkers with (CT+TT) genotypes had a significantly increased risk of GCC (OR=3.33, 95% CI:1.14-9.67). H pylori CagA negative subjects with (CT+TT) genotypes had a significantly increased risk of both IGC and GCC (OR=2.19 and 3.52, respectively). CONCLUSION: iNOS Ser^608 Leu allele may be a potential determinant of susceptibility to cigarette -alcohol induced gastric cancer, but larger studies are needed to confirm the observations.
文摘Objective To observe the effects of two main isoflavones, daidzein and genistein on the bone-nodule formation in rat calvaria osteoblasts in vitro. Methods Osteoblasts obtained from newborn Sprague-dawley rat calvarias were cultured for several generations. The second generation cells were cultured in Minimum Essential Medium supplemented with ascorbic acid and Na-beta-glycerophosphate for several days, in the presence of daidzein and genistein, with or without the estrogen receptor antagonist ICI 182780. Number of nodules was counted at the end of the incubation period (day 20) by staining with Alizarin Red S calcium stain. The release of osteocalcin, as a marker of osteoblast activity, was also determined on day 7 and day 12 during the incubation period. Results Compared with the control, the numbers of nodules were both increased by incubation with daidzein and genistein. 17β-estradiol was used as a positive control and proved to be a more effective inducer of the increase in bone-nodules formation than daidzein and genistein. The release of osteocalcin into culture media was also increased in the presence of daidzein and genistein, as well as 17β-estradiol on day 7 and day 12 (day 12 were higher). The estrogen receptor antagonist ICI 182780 completely blocked the genistein- and 17β-estradiol-induced increase of nodule numbers and osteocalcin release in osteoblasts. However, the effects induced by daidzein could not be inhibited by ICI 182780. Conclusion These findings suggest that geinistein can stimulate bone-nodule formation and increase the release of osteocalcin in rat osteoblasts. The effects, like those induced by 17β-estradiol, are mediated by the estrogen receptor dependent pathway. Daidzein also can stimulate bone-nodule formation and increase the release of osteocalcin in rat osteoblasts, but it is not, at least not merely, mediated by the estrogen receptor dependent pathway.
文摘Tuberous sclerosis (TS) is an autosomal dominant disorder with a significantrange of clinical expressions. The involvement of vital organs, such as the brain, kidney, heart andlung is the main cause of death in patients with TS. The aim of this study is to summarize thecharateristic cutaneous features and common extracutaneous involvement of TS, which are helpful tothe early detection of visceral involvement. The analyzed clinical data from 78 patients with TSincluded those from detailed history, physical and dermatological examination, cranial computedtomography ( CT) and magnetic resonance imaging ( MRI) , abdominal ultrasonography, chestroentgenography, hand and foot X-ray and ophthalmologic examination. The skin, brain and kidney wereinvolved frequently in TS patients. Hypomelanotic macules were the most common and earliestcutaneous lesions. Their number was more than 3 in 81. 5% of'the patients. They were followed byfacial angiofibromas and Shangreen' s patch in a decreasing frequency. Forehead plaque, facialangiofibromas and Shagreen's patch appeared in patients at mean age of 2. 6, 6. 0 and 8. 1 yearsrespectively. Cranial CT showed a high positive rate in TS patients . Cutaneous features of TS arehelpful in the early diagnosis of the disease. Hypomelanotic macules are especially important forpatients with epilepsy or babies whose number of hypomelanotic malues is more than 3. Cranial CT isof great value in the diagnosis of TS. The involvement of visceral organs such as the brain andkidney should be examined in TS patients.
文摘The in vitro inhibitory effect of trihydroxybenzoic acid dimer(TAD) extracted from Trapabispinosd roxb on HeLa cell growth was investigated via the MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diophenyl-tetrazolium bromide] reduction method. The morphological changes of HeLa cells were observed by means of an optical microscope and a transmission electron microscope(TEM); the cell circles and apoptosis were detected by a flow cytometer. It was found that TAD can significantly inhibit the growth of Hela cells and can induce the apoptosis of HeLa cells. It was also found that the inhibition to the growth of Hela cells and the induction to the apoptosis of HeLa cells have a dosage-dependent feature. The inhibiting rates of TAD with mass concentrations of 25.000, 12.500 and 6.250 mg/L to the HeLa cell growth were 52.04%, 34.44% and 23.72% after 30 h, respectively, while those with TAD mass concentrations of 100.000, 50.000, 25.000, 12.500, 6.250 and 3.125 mg/L showed positive correlation with a correlation coefficient value of r=0.9859(P<0.01) and a IC_ 50 value of 10.90 mg/L. Observed by means of TEM, the HeLa cells exposed to 25.000, 12.500 and 6.250 mg/L TAD showed apoptosis to various extents, shrinkage of the cell nuclei, condensation and margination of chromatin, and cavitation of mitochondrion. An apoptosis peak was detected via a flow cytometer. It can be drawn from the results that TAD extracted from Trapabispinosd roxb has an evident inhibitory effect on the proliferation of and an inductive effect on the apoptosis of HeLa cells, but has no obvious arrest action towards the cell circles of HeLa cells.
基金This work was supported by the Major State Basic Research Development Program of People's Republic of China (G1999055904) the Danone's Diet and Nutrition Research and Education Grant (DIC2002-08).
文摘Objective To investigate the relation of methionine synthase (MS) gene variation with congenital heart disease (CHD) phenotype. Methods One hundred and ninety three CHD patients (94 males and 99 females) and their biological parents (nuclear families) in Liaoning Province were selected as the case group, and another 104 normal persons (60 males and 44 females) and their parents without family history of birth defects as the control group. For all subjects the polymorphism of MS gene A2756G locus was examined by PCR-RFLP method. Results In offspring of the control group the frequencies of MS genotype (+/ -) and allele (+) were 10.7% and 5.3%, without existence of homozygote. The MS genotype distribution and allele frequencies of CHD patients and their mothers were not significantly different from the control (P > 0.05). The frequency of allele (+) in case fathers (5.0 %) was apparently lower than that in the control (9.1%, P=0.060), and the odds ratio (OR) was 0.53 (95% CI: 0.25-1.09). There was no difference in parents' genotype combination between the two groups, and in genotype distribution among different types of CHD. Analysis of genetic transmission indicated that mutation allele (+) existed transmission disequilibrium in CHD nuclear families. The percentage of allele (+) transmitted from parents was lower than that allele (-) with OR 0.26 (95% CI: 0.11-0.60). Conclusion MS gene variation in parents is associated with occurrence of CHD in offspring, and mutation allele (+) in parents may be related with the decrease of CHD risk in offspring.
基金This work was supported by Shanghai Municipal Committee of Science and Technology through grant 03DZ05052.
文摘Objective To determine the best statistical distribution of concentration data of major air pollutants in Shanghai. Methods Four types of theoretic distributions (lognormal, gamma, Pearson V and extreme value) were chosen to fit daily average concentration data of PM10, SO2 and NO2 from June 1, 2000 to May 31, 2003 in Shanghai by using the maximum likelihood method. The fit results were evaluated by Chi-square test. Results The best-fit distributions for PM10,SO2 and NO2 concentrations in Shanghai were lognormal, Pearson V, and extreme value distributions, respectively. Conclusion The results can be further applied to local air pollution prediction and control, e.g., the probabilities exceeding the air quality standard and emission source reduction of air pollutant concentration to meet the standard.
文摘Severe acute respiratory syndrome(SARS) is the first severe viral epidemic we encountered his century,which once spread in more than thirty countriesin2003.1 The etiological agent of SARS has beenc onfirmed to be a novel coronavirus,namely SARS coronavirus(SARS-CoV),2,3 and the first outbreak of SARS has been successfully controlled world wide,but the identification of SARS-CoV isolated from wildanimals,the emergence of some sporadic SARS cases laterafter that outbreak,all suggest that the recurrence of such an epidemic is not unlikely in the future.In this case,development of SARS vaccines and specific drugs is undoubtedlyessential to the control and prevention from the possible outbreak.4,5
基金This work was supported by the Major State Basic Research Development Program of People’s Republic of China (G1999055904)and the Danone’s Diet and Nutrition Research and Education Grant (DIC2002-08).
文摘To investigate the relationship between G1958A gene polymorphism of methylenetetrahydrofolate dehydrogenase (MTHFD) and occurrence of congenital heart disease (CHD) in North China. Methods One hundred and ninety-two CHD patients and their parents were included in this study as case group in Liaoning Province by birth defect registration cards, and 124 healthy subjects (age and gender matched) and their parents were simultaneously selected from the same geographic area as control. Their gene polymorphism of MTHFD G1958A locus was examined with PCR-RFLP, and serum folic acid and homocysteine (Hcy) levels were tested with radio-immunoassay and fluorescence polarization immunoassay (FPIA). Results There existed gene polymorphism at MTHFD G1958A locus in healthy subjects living in North China. The percentages of GG, GA, and AA genotype were 57.98%, 35.57%, and 6.45% respectively, and the A allele frequency was 24.23%, which was significantly different from Western population. No difference was observed when comparing genotype distribution and allele frequency between the case and control groups, so was the result from the comparison between genders. The A allele frequency of arterial septal defect patients’ mothers (10.87%) was significantly lower than that of controls (28.15%) (P=0.014), with OR=0.31 (95% CI: 0.09-0.84), and no difference in the other subgroups. The percentage of at least one parent carrying A allele in arterial septal defect subgroup (43.48%) was significantly lower than that in controls (69.64%) (P=0.017), with OR=0.34 (95% CI: 0.12-0.92). The analysis of genetic transmission indicated that there was no transmission disequillibrium in CHD nuclear families. Their serum folic acid level was significantly higher than that of controls (P=0.000), and Hcy level of the former was higher than that of the latter with no statistical significance (P>0.05). Serum Hcy and folic acid levels of mothers with gene mutation were lower than those of mothers with no mutation. Conclusion No
基金The current work was co-funded by Energy Foundation through grant G-0212-06632 and Shanghai Municipal Committee of Science and Technology through grants 03DZ05052 and 03ZR14009.
文摘Objective To obtain the exposure-response functions that could be used in health-based risk assessment of particulate air pollution in China. Methods Meta analysis was conducted on the literatures on air particulate matter and its adverse health outcomes in China and worldwide. Results For each health outcome from morbidity to mortality changes, the relative risks were estimated when the concentration of air particulate matter increased to some certain units. Conclusion The exposure-response functions recommended here can be further applied to health risk assessment of air particulate matter in China.
