UNLABELLEDOBJECTIVE To study the in vitro effect and mechanism of Ginkgo biloba Extract 50 (GBE50) for inhibiting beta-amyloid (Abeta)-induced oxidative stress in rats' hippocampal neurons.

METHODSThe primary hippocampal neurons were cultured in vitro and divided into 4 groups, i. e. the normal control group (Ctrl), the Abeta group, the propanediol control group (PDO), and the six GBE50 concentrations groups (5, 10, 25, 50, 100, and 200 microg/mL). Excepted the Ctrl group, neurons were induced to oxidative stress by 20 gmolLAbeta25-35. The MTT and fluorescent probes labeling were used to observe the effect of GBE50 with different concentrations on the cell viability and the generation of intracellular reactive oxygen species (ROS) in neurons. Furthermore, Western blot was used to detect the cytoplasmic/total cytochrome C (Cyto C) ratio and total intracytoplasmal Cyto C, and the effect of the expression of oxidative stress-related protein Cyto C and activated Caspase-3 in three GBE50 concentrations groups (25, 50, and 100 microg/mL).

RESULTSCompared with the Ctrl group, the cell vitality was obviously lowered and intracellular ROS generation significantly increased after induction of 20 micromol/L Abeta25-35 (both P < 0.05). Compared with the Abeta group, the cell vitality was evidently improved after treated with different GBE50 doses. Except for 10 microg/mL, the cell vitality could be obviously elevated along with increased drug concentrations (P < 0.05). Meanwhile, the intracellular ROS generation decreased significantly in each GBE50 dose groups (P < 0.05). Abeta could increase the cytoplasmic/total Cyto C ratio and enhance the activated Caspase-3 expression significantly (P < 0.05). Compared with the Abeta group, among the three concentrations of GBE50, the Cyto C ratio was obviously lowered in the 100 microg/mL GBE50 group (P < 0.05), and the expression of activated Caspase-3 significantly decreased in 50 microg/mL and 100 microg/mL GBE50 groups (P < 0.05).

CONCLUSIONS20 micromol/L Abeta25-35 could induce the generation of intracellular ROS in hippocampal neurons. GBE50 could inhibit Abeta induced intracellular oxidative stress of neurons through lowering the cytoplasmic/total Cyto C ratio and inhibiting the activation of apoptosis protein Caspase-3 expression.

Amyloid beta-Peptides ; toxicity ; Animals ; Cells, Cultured ; Cytochromes c ; metabolism ; Hippocampus ; metabolism ; Neurons ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; Peptide Fragments ; toxicity ; Plant Extracts ; pharmacology ; Rats ; Rats, Sprague-Dawley

Hainantoxin-IV (HNTX-IV) purified from the venom of the spider Selenocosmia hainana is a potent antagonist that acts on tetrodotoxin-sensitive (TrX-S) sodium channels. It is a 35-residue polypeptide and includes three disulfide bridges. In order to investigate the structure-function relationship of HNTX-IV, two mutants (S12A-HNTX-IV and R29A-HNTX-IV) of HNTX-TV in which Ser12 and Arg29 were replaced by Ala respectively, were synthesized by solid-phase Fmoc chemistry, followed by oxidative refolding of purified peptides under the optimal conditions. The synthetic mutants were analyzed by MALDI-TOF mass spectrometry, nuclear magnetic resonance spectroscopy (NMR) and electrophysiological experiments for molecular weight, conformation and physiological activity, respectively. The results show that the mutants and native HNTX-IV (nHNTX-IV) have almost identical three-dimensional structures. The bioactivity level of S12A-HNTX-IV is also about the same as that of nHNTX-IV, suggesting that Ser12 does not play any important role for the bioactivity of this toxin. The bioactivity of R29A-HNTX-IV is reduced by at last 155 times, indicating that Arg29 is a key residue relative to the bioactivity of HNTX-IV. It is presumed that the decrease in activity of R29A-HNTX-IV is due to the changes of the property in the binding site rather than the change in the basic conformation of the molecule.
Amino Acid Substitution ; Animals ; Mutation ; Sodium Channel Blockers ; Sodium Channels ; drug effects ; physiology ; Spider Venoms ; chemical synthesis ; genetics ; Structure-Activity Relationship ; Tetrodotoxin ; pharmacology

OBJECTIVETo explore the relationships between quality of life, negative life events, social support and suicide ideation among undergraduates in colleges.

METHODS3517 undergraduates in colleges were recruited by multistage stratified random clustered sampling method. Factors associated with suicide ideation were analyzed with logistic regression by scores of Beck Scale for Suicide Ideation(BSSI), Generic Quality of Life Inventory (GQOLI), Adolescent Self-rate Life Events Checklist (ASLEC), Social Support Rating Scale (SSRS) and a questionnaire on background information.

RESULTSThe rate of suicide ideation within 7 days was 14.1%, especially in females (15.96%), with single parent (23.79%) and disabled undergraduates (25.00%). The primary risk factors for suicide ideation were with low psychological function, material life, family/social support, lower availability of support and more negative life events.

CONCLUSIONThe prevalence of suicide ideation among these undergraduates was high, appropriate measures focusing on these risk factors should be implemented.

China ; epidemiology ; Cluster Analysis ; Female ; Humans ; Logistic Models ; Male ; Risk Factors ; Self-Injurious Behavior ; epidemiology ; Students ; psychology ; Suicide ; psychology ; Surveys and Questionnaires

Objective To determine the status of adverse childhood experiences (ACEs) and the association of multiple ACEs with both parental alcoholism and later personal alcohol abuse among Chinese medical students with a view of improving adolescent health and reducing alcohol abuse among them. Methods In this cross-sectional study, 2073 Chinese medical students completed a survey on ten categories of ACEs in Anhui province of China. The association of parental alcoholism with ACEs and personal lcohol abuse was assessed by logistic regression analyses. Results The adjusted odds ratio (OR) for each category of ACEs in the subjects whose parents (either fathers or mothers or oth) had alcohol abuse was 2 to 14 times higher than that inthose with parental alcoholism (P<0.05). Subjects with i-parental alcoholism had the highest likelihood of ACEs. Compared with the subjects without ACEs, the risk of personal alcohol abuse was increased by 2-4-folds in the subjects with ACEs, irrespective of parental alcoholism (P<0.05). The total number of ACEs (ACE score) had a graded relationship to 4 categories of personal alcohol abuse with or without parental alcoholism. The prevalence of personal alcohol abuse among the subjects with parental alcoholism was higher, which was ndependent of ACE scores. Conclusion The prevalence of ACEs is generally serious in China. Efforts should be made to prevent and treat children with ACEs and subsequently to reduce alcohol abuse and later problems.

BACKGROUNDNerve growth factor (NGF) is well-known for its important role in the development and maintenance of the nervous system. Along with its neurotrophic role, NGF has been detected in the testis of mouse, rat and human, suggesting an additional non-neurotrophic effect in the male reproductive system. The expression of β-NGF in the undescended testes (cryptorchidism) has not been detected at present. The aim of this study was to evaluate the expression of β-nerve growth factor mRNA and protein in experimental cryptorchidism.

METHODSA unilateral mechanical cryptorchidism model in the Sprague-Dawley rat was established and the expression of β-NGF with histologic changes in experimental cryptorchidism were investigated using one step quantitative real-time reverse transcription-polymerase chain reaction, in situ hybridization histochemistry, immunofluorescence and hematoxylin-eosin staining.

RESULTSThe expression of β-NGF mRNA and protein were both significantly decreased in the development of unmarred testis and cryptorchidism-induced testis, and the decrease of β-NGF in cryptorchidism-induced testis was far greater than that in uninjured testis.

CONCLUSIONFrom this investigation, we confirmed a lower expression of β-NGF in undescended testes than in the development of testis.

Animals ; Cryptorchidism ; genetics ; metabolism ; Male ; Nerve Growth Factor ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley

BACKGROUNDTissue Doppler imaging (TDI) has provided an objective means to quantify global and regional left ventricular (LV) and right ventricular (RV) function with improved accuracy and greater reproducibility than conventional echocardiography. This study was conducted to assess RV myocardial systolic activation by TDI in subjects with pulmonary arterial hypertension (PAH).

METHODSA total of 30 patients with PAH and 30 healthy volunteers, all comparable in age and sex, underwent standard Doppler echo and TDI. Using pulsed Doppler echocardiography combined with TDI, the following regional parameters were evaluated in three different myocardial segments (RV basal lateral wall, basal septal, and LV basal lateral) on apical 4-chamber view: systolic (Sm), early- and late-diastolic (Em and Am) peak velocities. RV myocardial systolic activation delay was defined as the difference in time to peak TDI systolic velocities between the RV basal lateral wall and basal septal. In addition, RV end-diastolic and end-systolic areas were measured to calculate RV fractional area change from the same apical 4-chamber view.

RESULTSCompared with the control group, patients with PAH showed increased RA and RV end-diastolic diameter (RA: (4.5 +/- 1.2) cm vs (3.0 +/- 0.8) cm, P < 0.05 and RV: (4.8 +/- 1.9) cm vs (3.4 +/- 0.5) cm, P < 0.05) and reduced RV fractional area change; (35 +/- 14)% vs (56 +/- 9)%, P < 0.05. These PAH patients showed lower myocardial peak velocities and a significant activation delay compared with controls (P < 0.05). Moreover, a strong correlation between RV myocardial systolic activation delay and RV fractional area change was shown in patients with pulmonary arterial hypertension (r = -0.82).

CONCLUSIONSIn PAH, RV myocardial systolic activation was markedly delayed, which was directly related to the RV fractional area change. RV myocardial systolic activation delay assessed by TDI could offer a unique approach to predict RV dysfunction.

Adolescent ; Adult ; Diastole ; Echocardiography, Doppler ; Female ; Humans ; Hypertension, Pulmonary ; physiopathology ; Male ; Middle Aged ; Systole ; Ventricular Dysfunction, Right ; etiology ; Ventricular Function, Right

OBJECTIVETo explore the feasibility of in vitro chondrogenesis by co-culture of chondrocytes and adipose-derived stromal cells (ADSCs) so as to confirm the hypothesis that chondrocytes can provide chondrogenic microenvironment to induce chondrogenic differentiation of ADSCs.

METHODSHuman ADSCs and porcine auricular chondrocytes were in vitro expanded respectively and then were mixed at the ratio of 7:3 (ADSCs: chondrocytes). 200 microl mixed cells (5.0 x 10(7)/ml) were seeded onto a polyglycolic acid/polylactic acid (PGA/PLA) scaffold, 8 mm in diameter and 2 mm in thickness, as co-culture group. Chondrocytes and ADSCs with the same cell number were seeded respectively onto the scaffold as positive control group and negative control group. 200 microl chondrocytes (1.5 x 10(7)/ml) were seeded as low concentration chondrocyte group. There were 6 specimens in each group. All specimens were harvested after in vitro culture for 8 weeks in DMEM plus 10% FBS. Gross observation, histology, immunohistochemistry, wet weight measurement and glycosaminoglycan (GAG) quantification were used to evaluate the results. Multiple-sample t-test statistics analysis was done to compare the difference of wet weight and glycosaminoglycan(GAG) content between the groups.

RESULTSCells in all groups had fine adhesion to the scaffold and could secrete extracellular matrix. In co-culture group and positive control group, cell-scaffold constructs could maintain the original size and shape during in vitro culture. At 8 weeks, cartilage-like tissue formed in gross appearance and histological features, and abundant type II collagen could be detected by immunohistochemistry. Wet weight and glycosaminoglycan(GAG) content of co-culture group were respectively (174 +/- 12) mg and (7.6 +/- 0.4) mg. There were respectively 75% (P < 0.01) and 79% (P<0.01) of those of positive control group. In negative control group, however, constructs shrunk gradually without mature cartilage lacuna in histology. In low concentration chondrocyte group, constructs also shrunk obviously with small amount of cartilage formation at the edge area of the construct, and wet weight was (85 +/- 5) mg, which was 37% (P<0.01) of that of positive control group.

CONCLUSIONSChondrocytes can provide chondrogenic microenvironment to induce chondrogenic differentiation of ADSCs and thus promote the in vitro chondrogenesis of ADSCs.

Adipocytes ; cytology ; Animals ; Cell Differentiation ; Cells, Cultured ; Chondrocytes ; cytology ; Coculture Techniques ; Humans ; Swine ; Tissue Engineering ; methods ; Tissue Scaffolds

OBJECTIVETo study the characteristics of cellular metabolism of mandibular condylar chondrocytes in repairing state of osteoarthrosis and investigate its role in the pathogenesis of the disease.

METHODSTemporomandibular joint osteoarthrosis model of rabbits was created by the partial resection of joint disc and confirmed with histological diagnosis. The chondrocytes were harvested from osteoarthritic condylar cartilage in the repairing state and cultured in vitro under the monolayer culture condition. The cellular expression of cartilaginous matrix protein, collagenase and growth factors between the osteoarthritic chondrocytes and the normal controls were measured with RT-PCR technique to outline the basic feature of the osteoarthritic cells.

RESULTSThe cultured cells were confirmed as chondrocytes with their ability of expression of collagen type II and Aggrecan. In the reactive repairing state of osteoarthrosis, the chondrocytes showed the imbalance of expression of ECM proteins, and increased expression of collagenase and endogenous growth factors such as IGF-1 and TGF-beta1.

CONCLUSIONSThis study found the active anabolism of the chondrocytes within the osteoarthritic condylar cartilage and the imbalance synthesis of cartilage matrix. These repairing attempts by the osteoarthritic chondrocytes may be impossible to restore the primary homeostasis within the condylar cartilage.

Animals ; Cartilage, Articular ; metabolism ; pathology ; Cells, Cultured ; Chondrocytes ; metabolism ; Extracellular Matrix ; genetics ; metabolism ; Male ; Mandibular Condyle ; metabolism ; pathology ; Osteoarthritis ; metabolism ; pathology ; RNA, Messenger ; genetics ; metabolism ; Rabbits ; Temporomandibular Joint Disc ; pathology ; Temporomandibular Joint Disorders ; metabolism ; pathology

OBJECTIVETo evaluate the benzene exposure level and cytopenia among the benzene exposed workers in Shanghai, China and to analyze the influential factors for the health of benzene-exposed workers.

METHODSA total of 3314 benzene-exposed workers, who were from 85 benzene-related enterprises selected by stratified random sampling based on enterprise sizes and industries, were included in the study. The time-weighted average (TWA) concentration of benzene in each workshop was measured by individual sampling and fixed point sampling, and the benzene exposure level in workshop was evaluated accordingly. The occupational health examination results and health status of benzene-exposed workers were collected.

RESULTSThe median of TW A concentrations of benzene was 0.3 mg/m3. The TWA concentrations measured at 7 ( 1.4%) of the 504 sampling points were above the safety limit. Of the 7 points, 3 were from large enterprises, 2 from medium enterprises, and 2 from small enterprises; 3 were from shipbuilding industry, 1 from chemical industry, and 3 from light industry. Of the 3314 benzene-exposed workers, 451 ( 13.6%) had cytopenia, including 339 males ( 339/2548, 13.3%) and 112 females ( 112/766, 14.6% ). There were significant differences in the incidence rates of leukopenia and neutropenia among the benzene-exposed workers of different sexes and ages (P<0.05); there were significant differences in the incidence rate of cytopenia among the benzene-exposed workers of different ages and working years ( P<0.05 ); there were significant differences in the incidence of neutropenia among the benzene exposed workers of different working years ( P<0.05).

CONCLUSIONMonitoring and intervention measures should be enhanced to protect the benzene-exposed workers in the large enterprises in shipbuilding industry and medium and private enterprises in chemical industry from occupational hazards.

Adolescent ; Adult ; Benzene ; toxicity ; China ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Pancytopenia ; chemically induced ; epidemiology ; Young Adult

The main factors which affected the isolation, purification and cultivation of Pinellia cordata protoplasts from leaves were studied. The results indicated that the optimum enzyme solution for P. cordata leaves was 13% CPW + 1.0% Cellulose +0.1% Pectolase, at pH 6.0, temperature (25-28 degrees C ) for 4 h. The sucrose density gradient centrifugation was adopted to purificate the protoplasts collected, when 25% sucrose was used as mediator, centrifugating at 500 rpm for 10 min. When the protoplasts were shallow liquid and liquid-solid double layer cultured on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA + 13% mannitol at the density of 2.5 x 104 protoplasts/mL, or fed and nursed cultured at the density of 100-500 protoplasts/mL, cell division could be observed for 3 days; granular calli appeared for 30 days. Calli was proliferated on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA solidified by 0.55% agar, and differentiated and regenerated after 5-6 months. Plant generation of P. cordata is successfully established.
Cell Separation ; methods ; Culture Media ; Pinellia ; physiology ; Protoplasts ; physiology ; Regeneration