Studying effects of 50 Hz sinusoidal electromagnetic fields (SEMFs) with different intensities on peak bone mass (PBM) of rats may provide a theoretical basis for application of electromagnetic clinical field. 30 female SD rats, 6 weeks of age, were randomly divided into three groups: the control group, 0.1 mT electromagnetic field group (EMFs) and 0.6 mT EMFs. The EMFs groups were treated for 3 h/day. After 8 weeks, we examined their bone mineral densities (BMD) , measured their bone biomechanical properties, and made serum levels of osteocalcin (OC), tartrate-resistant acid phosphatase 5b (TRACP 5b), and histomorphometry. It was found that the BMD (P < 0.01), maximum mechanical load (P < 0.01) in the 0.1 mT group were significantly higher than those in the control group, and Yield strength (P < 0.05), the analyses of serum bone turnover markers and histomorphometric parameters were better than those in the control group (P < 0.05). However, the 0.6 mT group did not have significantly difference comparing with that in the control group. This study proved that 50 Hz 0.1 mT SEMFs can increased BMD, bone strength, and bone tissue microstructure. Therefore, 50 Hz 0.1 mT SEMFs can improve peak bone mass of rats.
Acid Phosphatase ; blood ; Animals ; Bone Density ; Bone and Bones ; physiology ; Electromagnetic Fields ; Female ; Isoenzymes ; blood ; Osteocalcin ; blood ; Rats ; Rats, Sprague-Dawley ; Tartrate-Resistant Acid Phosphatase

OBJECTIVE: To explore the value of estimating chronologic age based on the grades of mandibular third molar development. To evaluate whether mandibular third molar could be used as an indicator for estimating the age under or over 18 years. METHODS: The mineralization status of mandibular third molar of 1 845 individuals aged 10 - 30 was graded and marked based on Demirjian's classification of grades reformed by Orhan. Gender difference was examined by t-test. A cubic regression model was established to analyze the correlation between third molar and chronologic age. Each grade of age cumulative distribution diagram and ROC curve was respectively performed to evaluate the relationship between third molar and the age of 18. Using Bayes discriminant analysis, an equation was established for estimating the age of 18. RESULTS: The inner-rater reliability was 0.903. Statistical analysis showed a moderate correlation between age and grade. Significant differences of both genders were found only in grade D and H (P < 0.05). Males at the grades from 1 to D and females at the grades from 1 to C were under 18 years old, and both males and females at grade H were over 18 years old. The area under the ROC curve was 0.797 (P < 0.05). CONCLUSION Third molar development shows a high correlation with age, and combined with other indicators, it can be used to estimate the age of 18.
Age Determination by Teeth/methods* ; Asian People ; Bayes Theorem ; China ; Female ; Forensic Dentistry ; Humans ; Male ; Molar, Third/diagnostic imaging* ; Radiography, Panoramic ; Reproducibility of Results ; Sex Characteristics

OBJECTIVE: To establish the linear regression equation between body height and combined length of manubrium and mesostenum of sternum measured by CT volume rendering technique (CT-VRT) in southwest Han population. METHODS: One hundred and sixty subjects, including 80 males and 80 females were selected from southwest Han population for routine CT-VRT (reconstruction thickness 1 mm) examination. The lengths of both manubrium and mesosternum were recorded, and the combined length of manubrium and mesosternum was equal to the algebraic sum of them. The sex-specific linear regression equations between the combined length of manubrium and mesosternum and the real body height of each subject were deduced. RESULTS: The sex-specific simple linear regression equations between the combined length of manubrium and mesostenum (x3) and body height (y) were established (male: y = 135.000+2.118 x3 and female: y = 120.790+2.808 x3). Both equations showed statistical significance (P < 0.05) with a 100% predictive accuracy. CONCLUSION CT-VRT is an effective method for measurement of the index of sternum. The combined length of manubrium and mesosternum from CT-VRT can be used for body height estimation in southwest Han population.
Asian People ; Body Height ; Female ; Forensic Anthropology ; Humans ; Linear Models ; Male ; Manubrium/anatomy & histology* ; Regression Analysis ; Sternum/anatomy & histology* ; Tomography, X-Ray Computed

Objective To explore the effect of secondary brain injury(SBI) in high-risk factors and brain malignant encephaiocele during surgical operation for severe traumatic brain injury. Methods Carried on the grouping graduation to 112 patients with severe traumatic brain injury according to SBI's high-risk factors:non-high-risk factors group (pure group) 23 cases, high-risk factors group (SBI group) 89 cases, 1 level of high-risk factors group had 27 cases, 2 level of high-risk factors group had 28 cases, 3 level of high-risk factors group had 34 cases. Results Carried on the comprehensive therapy regarding the above patients, the brain malignant encephalocele rate in the SBI group and the pure group was 59.55% (53/89) and 13.04%(3/23) respectively, there was significant statistics differences in the two groups,1 level and 2 level of high-risk factors group of brain malignant encephalocele rate was 40.74% (11/27) and 53.57% (15/28) respectively, the difference was not obvious statistics significance, 2 level and 3 level of high-risk factors group of brain malignant eneephalocele rate was 53.57%(15/28) and 79.41%(27/34) respectively, the difference was obvious statistics significance. Conclusions The SBI's high-risk factors are the important factors affecting severe craniocerebral injury encephalocele. Taking adequate pre-operative assessment, carrying a comprehensive treatment on the patients combine with high-risk factors of SBI can greatly reduced the incidence of brain malignant encephalocele during surgical operation if the high-risk factors of SBI is controlled.

OBJECTIVEGuanxin II is a famous modern formula of traditional Chinese medicine. Guanxin II after myocardial infarction (MI) has been shown to have beneficial effects on cardiac anatomy and function. The purpose of this study was to examine the effects of Guanxin 1I on cardiac protein expression after MI.

METHODRats were randomized into 3 groups, sham, model and treating groups. Model and treating groups were fed with Guanxin II and sham group was fed with water for 10 days before MI. MI operation is to ligate left coronary artery. 24 hours after MI, myocardial protein expression of junctional zone was assessed with 2D gel electrophoresis and mass spectra analysis.

RESULTGuanxin II was found to be able to improve myocardial protein expression, especially 11 proteins. These proteins are mainly involved in suppressing changes of cell shape and structure and energy metabolism.

CONCLUSIONGuanxin II after MI affected myocardial protein expression. Further experiments of larger research extent should be done to receive more results.

Animals ; Cell Shape ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Energy Metabolism ; drug effects ; Gene Expression Regulation ; drug effects ; Heart ; drug effects ; Male ; Muscle Proteins ; metabolism ; Myocardial Ischemia ; metabolism ; pathology ; Myocardium ; metabolism ; Rats

Objective To investigate the efficacy of using a calibrator with values assigned with the reference method for improving the comparability of serum gamma-glutamyltransferase (GGT) measurements.Methods The IFCC reference method for GGT was established and the performance was verified by testing a certified reference material (CRM).A calibrator was prepared and its value for GGT was assigned with the reference method.Forty serum samples were measured on different (including HITACHI 7600,7060,7170,7180 and BECKMAN LX20,OLYMPUS AU 400) chemistry analyzers with Zhongsheng GGT reagent kits calibrated with the calibrator.The samples were also measured on the same analyzers using a theoretical factor.Biases of results obtained with the calibration and with the theoretical factor based calculation were compared.Results The reference method resuhs on the CRM agreed the certified value within the stated uncertainty.Serum results calculated from the theoretical factor showed various biases and inter-analyzer variations.When the analyzers were calibrated with the calibrator,the number of results with biases less than 10% became significantly higher and those with biases more than 20% significantly lower.The variation of the results on 5 serum samples was reduced from 11.0%～14.0% to less than 5% by using the calibrator.Conclusion Accuracy and comparability of GGT measurements with of ZhongSheng GGT kits can be improved by using a calibrator that has a value assigned with the reference method.

AIM AND METHODSBy using blind whole-cell recording techniques, the dynamic properties of voltage-gated Ca2+ channel of CA1 pyramidal neuron in rat hippocampal slices were investigated.

RESULTSThe voltage-gated Ca2+ channel of CA1 pyramidal neuron in rat hippocampal slices has following features: (1) The threshold potential of activation is relatively lower. The mean value is -49.3 +/- 8.6 mV with range from -65 to -30 mV (n = 23). (2) Current decay is Ca(2+) -dependent and its time constant (tau) is longer with a wide range from 100 to 700 ms (n = 12). (3) The steady-state inactivation is voltage-dependent and the half inactivation potential (V1/2) is -55.4 +/- 9.7 mV, slope factor (k) is 5.3 +/- 0.9 (n = 10). (4) The reversal potential (E(rev)) of Ca2+ channel is 55 +/- 13 mV (n = 10) when extracellular Ca2+ concentration is 2.5 mmol/L. (5) Tail current, which is voltage-independent, primarily has only one component. In addition, Ca2+ channel is insensitive to verapamil and nifedipine.

CONCLUSIONN-type Ca2+ channel is strongly suggested in CA1 pyramidal neuron in rat hippocampal slices.

Animals ; Calcium Channels ; metabolism ; physiology ; Hippocampus ; cytology ; physiology ; In Vitro Techniques ; Male ; Patch-Clamp Techniques ; methods ; Pyramidal Cells ; metabolism ; physiology ; Rats ; Rats, Wistar

OBJECTIVETo analyse the relationship between coping strategy and occupational stress in rail freight dispatchers.

METHODS115 rail freight dispatchers were investigated by using group sampling method, investigation contents included coping strategies, occupational stressors, strains and personalities.

RESULTSThe proportion of using coping strategy in rail freight dispatchers is lower. The scores of job future ambiguity, type A behavior and work locus of control in workers with insufficient coping strategy were higher than those in workers with sufficient strategy (P < 0.05 or P < 0.01), but the score of organization commitment score in workers with insufficient coping strategy was lower than those in workers with sufficient strategy (P < 0.05), the differences of scores of some occupational stressor, strain and personality variables between workers with insufficient and those with sufficient in social support, job-family balance, job involvement coping factors of coping strategy were remarkable significant (P < 0.05 or P < 0.01), the differences of scores of occupational stressor, strain and personality variables between workers with insufficient and those with sufficient in ask, logic and time management factors of coping strategy weren't significant (P > 0.05). Logistic regression analysis showed that risk of being job dissatisfaction and daily life stress in workers with insufficient social support coping was three or four times than those with sufficient coping (OR = 3.06 or 4.38, respectively), risk of being daily life stress in workers with insufficient job involvement coping was three times than those with sufficient coping (OR = 3.26).

CONCLUSIONThe proportion of using coping strategy in rail freight dispatchers is lower. Coping strategy has influence on the individual's perception of occuaptional stressors, strains and personalities.

Adaptation, Psychological ; Adult ; Burnout, Professional ; psychology ; China ; Humans ; Middle Aged ; Occupational Diseases ; psychology ; Occupational Health ; Personality ; Railroads ; Social Support ; Stress, Psychological ; psychology

Objective To investigate the effect of asterone on airway epithelial cell autophagy and its mechanism through LPS-induced airway epithelial cell inflammation model.Methods Beas-2B cells(human bronchial epithelial cells)were induced by LPS to construct an inflammation model.The effect of asterone on the proliferative activity of Beas-2B cells was detected by CCK-8.The levels of IL-6 and TNF-a in the cells were detected by ELISA.The expression levels of NF-κB and AP-1 in each group of cells were detected by RT-PCR.The relative expression of NF-κB、p-NF-κB、AP-1、Beclin 1、LC3-Ⅱ、LC3-Ⅰ、mTOR、p-mTOR、p-S6K1 and S6K1 was detected by Western blotting.The changes of autophagy in each group of cells were observed by acridine orange staining.Results Compared with the control group,the relative expression of AP-1 and p-NF-κB was signifi-cantly higher than that of LPS group(P＜0.05);orange and red fluorescence with many dotted red spots of acidic membrane vesicles as well as increased autophagy level were observed in cells;the relative expressions of Beclin 1 and LC3-Ⅱ were signifi-cantly increased in cells(P＜0.05),and expressions of LC3-Ⅰ,p-mTOR and p-S6K1 were significantly reduced(P＜0.05).Compared with the LPS group,the relative expressions of AP-1 and p-NF-κB in the LPS+asterone group were significantly de-creased(P＜0.05);less orange and red fluorescence was observed in cells,and the level of autophagy was decreased(P＜0.05).The relative expressions of Beclin 1 and LC3-Ⅱ were reduced(P＜0.05).The expressions of LC3-Ⅰ,p-mTOR and p-S6K1 were increased.Conclusion Asterone can inhibit the occurrence of autophagy in Beas-2B inflammatory cells,and the mechanism may be related to activation of mTOR signaling pathway.

Objective To summarize the characteristics of acupoints selection in acupuncture-moxibustion treatment of primary dysmenorrhea (PD) based on data mining. Method Clinical literatures published in the recent 10 years related to acupuncture-moxibustion treatment of PD were collected to establish a prescription database by using Excel. The descriptive analysis, association rules analysis and clustering analysis were conducted by Python and Clementine12.0. Result A total of 74 acupoints were involved with a total frequency of 1072. The leading three meridians were Spleen Meridian (325 times), Conception Vessel (260 times) and Bladder Meridian (158 times); the leading acupoints were Sanyinjiao (SP6, 174 times), Guanyuan (CV4, 111 times), Diji (SP8, 79 times), Ciliao (BL32, 73 times) and Qihai (CV6, 67 times). The utilization of the specific acupoints accounted for 66.22% (49/74). The crossing acupoints were predominant (393 times), especially Sanyinjiao, Guanyuan and Zhongji (CV3), followed by the five-Shu points (195 times), Front-Mu points (195 times) and Yuan-Primary points (99 times). The association rules analysis showed that Guanyuan and Sanyinjiao had the most significant correlation. The clustering analysis figured out 8 core clustering groups. Conclusion The characteristics of acupoints selection revealed in this study provide ideas and references for acupuncture-moxibustion treatment of PD in clinic.