OBJECTIVETo investigate the effect of retinoic acid on differentiation of periodontal ligament cells (PDLCs) and gingival fibroblasts (GFs).

METHODSThe periodontal ligament cells and gingival fibroblasts were cultured, challenged with different concentrations of retinoic acid in medium and detected for the alkaline phosphatase (ALP) activity and its mRNA by biochemical technique, in situ hybridization and RT-PCR.

RESULTSALP activity in normal PDLCs was higher than that in GFs. The mRNA signals were positive in PDLCs, and negative in GFs. After treated with different concentrations of retinoic acid, ALP activity of PDLCs was increased than that of the control, and its mRNA signals were enhanced, especially in 5 x 10(-6) mol/L. The treated GFs showed a slight increase of ALP activity and a weak band of mRNA signals only in 5 x 10(-6) molUL concentration.

CONCLUSIONThere were differences between PDLCs and GFs in differentiating into osteoblast-like cells.

Cell Differentiation ; Fibroblasts ; Gingiva ; Osteoblasts ; Periodontal Ligament ; RNA, Messenger ; Tretinoin

OBJECTIVETo observe the effect of natural type ginsenoside Rg2 (Rg2) and its stereoisomers [20 (R)-Rg2 and 20 (S)-Rg2] at different concentrations on oxygen-glucose deprivation/ reperfusion (OGD/R) induced cortical neuronal injury model in vitro, and to explore the mechanism, and compare their differences of action.

METHODSCortical neurons after 7-day culture were randomly divided into 5 groups, i.e., the control group, the model group, the Rg2 group, 20 (R) -Rg2 group, and 20 (S) - Rg2 group. Cortical neurons in the Rg2 group, 20 (R)-Rg2 group, and 20(S)-Rg2 group were pretreated with 20, 40, and 80 μmol/L Rg2, 20 (R) -Rg2, and 20 (S) -Rg2 for 24 h to prepare OGD/R model. The cell survival rate, the activity of Caspase-3, the intracellular Ca2+ concentration, contents of superoxide dismutase (SOD) and malondialdehyde (MDA) were detected 24 h later.

RESULTSCompared with the control group, cell survival rates and activities of SOD obviously decreased, the activity of Caspase-3, Ca2+ fluorescent optical gray value, and contents of MDA significantly increased with statistical difference (P < 0.05). Compared with the model group, cell survival rates and activities of SOD obviously increased, the activity of Caspase-3, Ca2+ fluorescent optical gray value, and contents of MDA significantly decreased in 20 μmol/L Rg2 group, 40 μmol/L 20 (R) -Rg2 group, and 80 μmol/L 20 (S) -Rg2 group (P < 0.05). Compared with 20(S)-Rg2 group, cell survival rates increased and contents of MDA significantly decreased in 20, 40, and 80 μmol/L Rg2 and 20 (R)-Rg2 groups (P < 0.05). The activity of Caspase-3 decreased and contents of SOD increased in 80 μmol/L 20 (R)-Rg2 group, and 40, 80 μmol/L Rg2 groups (P < 0.05). Ca2+ fluorescent optical gray value decreased in 40, 80 μmol/L Rg2 and 20 (R)-Rg2 groups (P < 0.05). Compared with 20 (R)-Rg2 group, Ca2+ fluorescent optical gray value decreased in 80 μmol/L Rg2 group (P < 0.05); contents of SOD increased in 40 and 80 μmol/L Rg2 groups (P < 0.05); contents of MDA decreased in 20, 40, and 80 μmol/L Rg2 groups (P < 0.05).

CONCLUSIONSRg2 and its stereoisomers could improve cell vitality of cortical neurons against OGD/R induced injury. This might be related to improving anti-apoptotic capacities and antioxidant abilities, and reducing Ca2+ inflow. Besides, the neuroprotective effect of 20 (R) -Rg2 was better than that of 20 (S) -Rg2, but inferior to that of Rg2.

Antioxidants ; metabolism ; Apoptosis ; Calcium ; metabolism ; Caspase 3 ; metabolism ; Cell Survival ; Cells, Cultured ; Ginsenosides ; pharmacology ; Glucose ; Humans ; Malondialdehyde ; metabolism ; Neurons ; drug effects ; Neuroprotective Agents ; pharmacology ; Oxygen ; Random Allocation ; Reperfusion Injury ; Stereoisomerism ; Superoxide Dismutase ; metabolism

OBJECTIVETo investigate the prevalence of chronic obstructive pulmonary disease (COPD) and its risk factors in population over 40 years old in northern part of Guangdong province.

METHODSUsing uniform scheme, procedures and questionnaire, a cluster-randomized-sampling survey for the population aged over 40 years in a rural area of Shaoguan in the northern part of Guangdong province was performed. Spirometry was performed for every participant, followed by a bronchodilatation test when bronchial obstruction was present.

RESULTSThere were 1468 cases with complete data from 1498 people aged >or= 40 years including 640 males, 828 females with an average age of 54.3 years old. The total prevalence of COPD was 12.0%. The prevalence of COPD in males was significantly higher than that in females (18.3% vs. 7.1%, P < 0.01). Only 80.7% of the patients with COPD presented one or more symptoms as cough, phlegm, or dyspnoea. Underdiagnosis of COPD would be quite serious. Only 26.1% of the cases was previously diagnosed to have chronic bronchitis, emphysema, or COPD. Smoking was an important risk factor to COPD and 78.4% of the patients with COPD were smokers. However, relation of biomass and COPD called for further investigation.

CONCLUSIONPrevalence of COPD was much higher than expected in the northern part of Guangdong while smoking was an most important risk factor of COPD. Lung function test seemed to be of great importance to COPD diagnosis, especially in the earlier period of COPD.

Adult ; China ; epidemiology ; Female ; Humans ; Male ; Mass Screening ; Middle Aged ; Prevalence ; Pulmonary Disease, Chronic Obstructive ; epidemiology ; Risk Factors ; Sex Factors ; Smoking ; adverse effects ; Surveys and Questionnaires

OBJECTIVETo explore the methodology on prevalence study of chronic obstructive pulmonary disease (COPD) in line with the world, to obtain accurate epidemic data of COPD in China.

METHODSA national multi-center cross-sectional survey on prevalence, risk factors and burden of COPD was conducted in China. In each area, a population-based cluster sample of approximately 1450 individuals aged 40 years or older was interviewed, using standardized questionnaires that were revised on the methodology of burden of lung diseases (BOLD) study and according under the context of China. All participants were submitted to pre-bronchodilator spirometry. Those with airflow limitation received post-bronchodilator spirometry, physical examination, X-rays of chest and EKG (electrocardiogram) tests. The post-bronchodialators FEV1/FVC < 70% was identified as having COPD.

RESULTSInvestigation has been completed with the same standardized procedures by all sites, up to the requirement of quality control. Over 85.0% of the spirometry tests and 95.0% of questionnaires had met the criteria of quality control in each area. Overall, 95.2% of the data was valid with acceptable spirometry and questionaire, and the valid response rate was 79.0%.

CONCLUSIONThe protocol was in line with the international standards, by which the prevalence of COPD in China was of adequate quality and valid.

Adult ; China ; epidemiology ; Epidemiologic Studies ; Humans ; Prevalence ; Pulmonary Disease, Chronic Obstructive ; epidemiology

BACKGROUNDChronic obstructive pulmonary disease (COPD) has a variable natural history and not all individuals follow the same course. This study aimed to identify the prevalence and characteristics of asymptomatic COPD patients from a population-based survey in China.

METHODSA multistage cluster sampling strategy was used in a population from seven different provinces/cities. All residents (over 40 years old) were interviewed with a standardized questionnaire and spirometry. Post-bronchodilator forced expiratory volume in 1 second (FEV(1))/forced vital capacity (FVC) of less than 70% was defined as the diagnostic criterion of COPD. All COPD patients screened were divided into symptomatic group and asymptomatic group according to the presence or absence of chronic respiratory symptoms. Socio-demographic, personal and exposure variables were collected and analyzed.

RESULTSAmong the 1668 patients who were diagnosed with COPD from the 25 627 sampling subjects, 589 (35.3%) were asymptomatic. The age, sex, body mass index (BMI), rural and urban distributions, smoking habit and education levels were similar in the two groups. A total of 64.7% of the asymptomatic patients had no comorbidities. Cardiovascular diseases and lung cancer were more common among symptomatic COPD patients than asymptomatic group. Asymptomatic COPD group were less likely to present with poor ventilation in the kitchen, a family history of respiratory disease and recurrent childhood cough. Asymptomatic COPD patients had significantly higher FEV(1) (73.1% vs. 61.0%), FVC (91.9% vs. 82.0%), and a higher ratio of FEV(1)/FVC (62.9% vs. 58.7%) (all P < 0.001) than symptomatic group. More asymptomatic patients were underdiagnosed (91.9% vs. 54.3%, P < 0.001) than symptomatic patients.

CONCLUSIONSThis large population-based survey confirmed a high prevalence of asymptomatic COPD patients in China. More use of spirometry screening test may be important to the early detection of COPD.

Adult ; Aged ; Aged, 80 and over ; China ; epidemiology ; Educational Status ; Female ; Humans ; Male ; Middle Aged ; Pulmonary Disease, Chronic Obstructive ; diagnosis ; epidemiology ; Risk Factors ; Smoking ; Spirometry ; Surveys and Questionnaires