The biomarkers can facilitate the evaluation of the factors modulating susceptibility to carcinogens among human populations. As an indicator of DNA damage, carcinogen-DNA adducts represent a critical step on the carcinogenic pathway. Genetic differences in detoxification capabilities and the DNA repair efficiency may modulate PAH-induced DNA damage and carcinogenesis. Experimental animal studies have demonstrated that the fetus and infant are more susceptible to polycyclic aromatic hydrocarbons (PAHs) induced carcinogenesis than adults. Recent years, more and more studies have shown that the prenatal exposure to PAHs not only associated with the increasing risk of cancer, but also related to adverse birth outcomes. This paper reviewed the differential susceptibility to PAHs between the paired maternal and newborn and discussed the relationship between the DNA adducts levels and the gene polymorphisms.

Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Humans ; Phytotherapy ; methods ; Pulmonary Disease, Chronic Obstructive ; drug therapy

Objective To study the prospective memory and the severity of the impairment of event- based prospective memory(EBPM)and time-based prospective memory(TBPM)in normally aging adults. Methods We set a neuropsychological battery to measure the education-matched 40 adults and 40 normally aging adults who were given EBPM and TBPM tasks.Results Compared with the young controls(EBPM, 6.25?1.60;TBPM,5.38?0.87),both EBPM(2.50?0.85)and TBPM(4.93?1.07)in the elderly had been impaired,especially EBPM(t = 13.117,P

BACKGROUND: Ultrasound-medium frequency electrotherapy has better pain-relieving effect,whether it involves enkephalin and the like neurotransmitter is still not very clear, it is necessary to carry out qualitative and quantitative analysis of the pain response in rats received ultrasound-medium frequency electrotherapy.OBJECTIVE: To investigate the pain-relieving effect of ultrasound-medium frequency electrotherapy and its influence on the enkephalin content in rats, aiming to probe its underlying mechanism and relationship with neurotransmitter enkephalin.DESIGN: Randomly controlled study taking experimental animals as subjects.SETTING: Department of Physiotherapy, First Hospital Affiliated to China Medical University, Institute of Basic Medicine, Peking Union Medical CollegeMATERIALS: This experiment was carried out at the Institute of Basic Medicine, Peking Union Medical College between June 2002 and March 2003. Forty healthy male Wistar rats were adopted and randomized into four groups,namely methionine enkephalin detection experimental group and control group,as well as leucine enkephalin detection experimental group and control group with 10 rats in each group ,amongst which methionine enkephalin experimental group and leucine enkephalin experimental group were generally designed as experimental group ,with the other two group as control group.METHODS: ①Rats ín the experímental group were subjected to ultrasound-medium frequency electrotherapy with frequency of 0.8 MHz in manner of geminal pulse,the modulatìng frequency was 100 Hz and ultrasound intensity of 0.9 W/cm2;the carrier frequency of medium frequency electricity was 4 kHz with modulating frequency of 100 Hz in manner of continuous wave,the electric current of medium frequency was 2 mA and acting time of 10 min. rats in control group received the same dealing,but the higher voltage of ultrasound-medium frequency electrotheprauetic instrument was not used, thereby no energy output was available. tail flick test(TFr) was used to test rat algesthesia,and stopwatch was used to record the time for tail flick(s) that was taken as the value of pain threshold. ②The threshold of pain was tested at 10 minutes instantly after ultrasoundmedium frequency electric stimulation,and then pituitary (removing the posterior pituitary lobe) and hypothalamus were obtained to detect the content of methionine enkephalin and leucine enkephalin by using radioimmuno assay.MAIN OUTCOME MEASURES: The changes of the pain threshold after treatment,the content of methionine enkephalin and leucine enkephalin.RESULTS: Totally 40 rats were enrolled in the experiment and entered in the results analysis. ① The changing rate of pain threshold in two experimental group were 265.79% and 272.90% respectively,the difference was of no statistical significance (P ＞ 0.05). ②After ultrasoundmedium frequency electrotherapy,the content of methionine enkephalin and leucine enkephalin in pituitary and hypothalamus were obviously higher than before treatment [ The changing rate of methionine enkephalin and leucine enkephalin in adenohypophysis was 300.48 ±36.21)% and(204.61±68.65)% , respectively, compared to (239.80±59.98)%and(205.53±51.62)% in hypothalamus, P ＜ 0.05]. ③Linear regression analysis revealed that the variance of the pain threshold was positively correlated with the content of methionine enkephalin in adenohypophysis(r=0.91 ,P ＜ 0.01), suggesting the increment of methionine enkephalin in adenohypophysis was closely connected with the increment of pain threshold,and the level of methionine enkephalin in adenohypophysis would be higher than that in control group by 117.02% when the value of pain threshold increased by100%.CONCLUSION: One of the important mechanisms for the pain-relieving effect of ultrasound-medium frequency electrotherapy might be the increase of methionine enkephalin in adenohypophysis.

Objective To evaluate the expression and correlat ion of hTERT and p21(WAF1/CIP1) in colonic carcinoma. Methods A total of 45 cases of normal colonic carcinoma, 10 cases of colonic adenoma s and 10 cases of normal colonic tissues were studied using in situ hybridization (ISH) and immunohistochemical techniques. Results hTERT and p21 were found not only in colonic carcinoma (t he positive rate being 88.9% and 46.7%, respectively ), but also in colonic aden omas (the positive rate being 50.0% and 10.0%, respectively). The positive rate of hTERT expression increased significantly in advanced stage (C+D) of colonic c arcinoma ( P

This article introduces a novel scavenger for waste anesthetic gas which makes use of negative pressure in operating room. This setting can scavenge the exhaust gas absolutely without affection the normal work of anaesthesia.
Anesthetics ; Gas Scavengers ; Operating Rooms

Objective To assess the effectiveness of absorbable screws and metallic devices for treating tibial plateau fractures.Methods Fifty-seven cases of tibial plateau fractures were treated with internal fixation using absorbable screws(Group A),cannulated screws(Group B)and condylar buttress plates(Group C)in our hospital.According to Schatzker classification,there were 15 cases with typeⅠfractures,21 with typeⅡ,nine with typeⅢand 12 with typeⅣ,who were followed up for 6-51 months. Statistical analysis was performed to compare bone union and functional restoration of the knee between three groups.Results Bone union was achieved in all cases.Based on Merchant scale for knee func- tion,excellence rate was 84%(16/19)for Group A,92%(11/12)for Group B and 85%(22/26) for Group C,with no significant statistical difference.Conclusion Absorbable screws is as effective as metallic devices for treating tibial plateau fractures and has advantages of minimal invasion,few complica- tions and avoiding secondary operation.

Objective To determine the cellular localization and expression pattern of AR and FSHR in adult rat testis must be helpful to understand the action site and mechanisms that T and FSH regulate spermatogenesis. Methods We applied in situ Hybridization to detect the expression of AR and FSHR on adult testis, in which Dig labeled cRNA probe was used to carry out the experiment on frozen sections; at the same time, following the technique of transillumination assisted microdissection we separated seminiferous epithelium into four stages(Ⅱ Ⅵ,Ⅶ Ⅷ,Ⅸ Ⅻ and ⅩⅢ Ⅰ), extracted total RNA and carried out dot hybridization, using ? 32 P labeled cDNA probe, in order to test qualitatively and quantitatively the location of AR and FSHR mRNA and their expression pattern in adult rat testis. Results Our results showed that the positive signal of AR mRNA was located in Sertoli cells and Leydig cells. The signal in Sertoli cells began to appear in Ⅱ Ⅵ stages, strongest in Ⅶ Ⅷ stages and weakest in Ⅸ Ⅰ stages ( P

Objective To investigate the transcription and protein expressions of chemokines CL16, CL12 and their receptors CR6, CR4 in first-trimester human cytotrophoblast cells and human choriocarcinoma cell line JAR. Methods Transcriptions of CR6, CL16, CR4, CL12 in purified first-trimester human trophoblast cells and JAR line were assessed by semi-quantitative RT-PCR, and protein expressions of CR6, CL16, CR4, CL12 were analyzed in primary cultured villous cytotrophoblasts (VCT), extravillous cytotrophoblasts (EVCT), JAR line and placentas by immunostaining. Results CR6 and CR4 were highly transcribed in primary cultured trophoblast cells with mRNA relative level of 1.12?0.25 and 1.08?0.11 respectively, and their ligands CL16 and CL12 were transcribed moderately with mRNA relative level of 0.89?0.11 and 0.78?0.10 respectively. It was demonstrated that CL16, CL12, CR6 and CR4 were expressed in primary cultured VCT, EVCT, JAR line and placentas by immunostaining. Conclusion The co-expression of CL16/CR6 and CL12/CR4 in trophoblast cells may play a role in the proliferation and differentiation of first-trimester trophoblast cells in a manner of autocrine.