Objective To study the impact of physical stimulus on periosteal chondroplasia with an in- tention of reconstructing cartilage tissue that has a biomechanical function and can be created either entirely in vivo or in vitro and subsequently implanted into the patient.Methods A series of biomechanical test methods were designed in order to investigate the mechanical properties of engineered cartilage under a variety of mechanical stress stimulations.The periosteal explants were harvested from proximal medial tibias of New Zealand rabbits and secured onto poly-?-caprolactone(PCL)scaffolds.The composites(periosteum/PCL)were suspended in the spinner flask bioreactor and the spinner flask was located on the stirring machine.The stem cells were stimulated by fluid shear stress under magnetic bar stirring.Results In gross observation,the thickness and length of neo-cartilage with shear force stimulation were significantly greater than those without shear force.The direction of elongation was parallel with fluid flow direction,regardless of composite orientation.Secondary,two different zones based on various cell morphology and distribution were clearly observed.The thickness of the superficial zone was greater in samples exposed to high shear force compared with low shear force.The superficial zone protein and lubricant were found in the engineered cartilage under shear stress stimulation.Conclusion The results reveal that shear stress can not only influence proliferation and differentiation of stem cells,but also change chondrocyte morphology and increase extracellular matrix production.

BACKGROUND:Early detection and accurate staging diagnosis of heart failure are the basis of good clinical therapy efficacy. Due to lack of simple and effective staging model for the diagnosis of heart failure, it is difficult to diagnose heart failure in clinics, leading to poor control of heart failure. OBJECTIVE:To establish the disease staging model based on Adaboost and SVM for heart failure, and improve the accuracy of diagnosis and staging of heart failure. METHODS:A total of 194 cases were roled into this study, including heart failure patients and healthy physical examination persons. According to the stage standards formulated by American Colege of Cardiology and American Heart Association, specific clinical feature parameters closely related to heart failure were colected and selected. Based on clinical diagnosis results and using Adaboost model and SVM model, we trained the models for heart failure diagnosis and staging, thus obtaining diagnosis model. RESULTS AND CONCLUSION: The parameters included stroke volume, cardiac output, left ventricular ejection fraction, left atrial diameter, left ventricular internal diameter at end-systole, N-terminal pro-brain natriuretic peptide and heart rate variability. As for the Adaboost model, its sensitivity and specificity was 100% and 94.4%, respectively. At the same time the SVM model had good sensitivity and specificity, 86.5% and 89.4% respectively. Adaboost classification model can be accurate in the diagnosis of heart failure symptoms, the accuracy reached 89.36%. On the basis of the diagnosis of heart failure, the SVM classification model is effective in staging the severity of heart failure, staging accuracy for staging B and C was 86.49% and 81.48%, respectively. The findings indicate that, combining Adaboost and SVM machine learning models could provide an accurate diagnosis and staging model for heart failure.

OBJECTIVETo develop the knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for occupational groups, and to provide a convenient and effective tool for the survey of knowledge, attitude, and behavior on the prevention and control of occupational diseases in occupational groups and the evaluation of intervention effect.

METHODSThe initial questionnaire which was evaluated by the experts was used to carry out a pre-survey in Guangzhou, China. The survey results were statistically analyzed by t test, identification index method, correlation analysis, and Cronbach's a coefficient method. And then the questionnaire was further modified, and the content of the questionnaire was determined finally.

RESULTSAfter modification, there were 18 items on knowledge, 16 items on attitude, and 12 items on behavior in the "Knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for enterprise managers"; there were 19 items on knowledge, 10 items on attitude, and 11 items on behavior in the "Knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for workers".

CONCLUSIONThe knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for occupational groups is developed successfully, and it is a convenient and effective tool for the survey of knowledge, attitude, and behavior on the prevention and control of occupational diseases in occupational groups and the evaluation of intervention effect.

China ; Health Knowledge, Attitudes, Practice ; Humans ; Occupational Diseases ; prevention & control ; Surveys and Questionnaires

Objective To improve the teaching methods of graduate students, and provide the theoretical basis for other teaching hospitals to extend the preclinical training mode of clinical medicine professional degree students. Methods 90 clinical medical postgraduate students of Grade 2012 were divided into four groups according to their specialized field and 54 hours of pre-job clinical intensive training were conducted at the same time. The training included four modules lectured by teachers with physician-in-charge above title, such as communication between doctors and patients and medical history collection, physical examination, medical record writing as well as theory of knowl-edge. Before and after the implementation of intensive training, these four skills and knowledge of the students were tested and assessed by professional teachers. Relevant data were paired t test, ANOVA and non-parametric tests. Results The test results of patient-doctor communication and patient history collection, physical examination, complete medical records and theoretical examination results of each group after training were improved to be higher than before (P<0.05). And the effect of patient-doctor communication and patient history collection was the most significant. The doctor-patient communica-tion and history acquisition performance of different groups of graduate students had statistically sig-nificant difference (P=0.001). Conclusion Strengthening the preclinical comprehensive training for medical postgraduate can make the students master the basic clinical skills better and more effectively and the corresponding training methods are worthy of popularization to the other teaching hospitals.

Objective To investigate the effect of adenovirus-bone morphogenic protein 9 ( Ad-BMP9 ) on osteogenic differentiation of immortalized calvarial mesenchymal progenitor cells ( iCALs ) .Methods iCALs were infected with adenoviral vectors encoding BMP-9 or green fluorescent protein ( GFP) and the early osteogenic differentiation was assessed by detecting alkaline phosphatase (ALP) activity after being cultured for 3, 5 and 7 days.14 days after infection, alizarin red S staining was performed to study the formation of osteogenic calcium nodules .The expression of osteogenic marker genes Runx2 and OCN was assessed by quantitative real-time ( RT )-PCR and Western blotting .Results Significant increases in ALP activity and in the expressions of Runx 2 and OCN were detected in BMP-9 treated iCALs compared with GFP-treated cells(P<0.05).Meanwhile, alizarin red S staining showed that more mineralized nodules were found in the BMP-9 induced group .Conclusion BMP-9 can promote the osteogenic differentiation of iCALs .

OBJECTIVE: To analyze the characteristics of medical malpractice from different grades of hospitals and to explore forensic investigation strategies in assessing medical dispute. METHODS: A total of 206 cases of medical dispute from 2009 to 2010 investigated by the Department of Forensic Medicine in Nanjing Medical University were selected and analyzed according to fault incidence, fault-prone part, and degree of causality in the treatment. RESULTS: Among the 206 cases analyzed, tertiary hospitals, secondary hospitals and primary hospitals showed medium, high and low error rate, respectively. A majority of medical malpractice cases were distributed in the departments of surgery, medicine and gynecology. CONCLUSION The frequency and severity of medical malpractice in primary hospitals were high, which were gradually reduced in tertiary and secondary hospitals.
Dissent and Disputes ; Expert Testimony ; Forensic Medicine ; Gynecology/statistics & numerical data* ; Hospital Departments/statistics & numerical data* ; Humans ; Incidence ; Malpractice/statistics & numerical data* ; Medical Errors/statistics & numerical data* ; Retrospective Studies ; Time Factors

Objective To investigate clinical characteristics of relapsing polychondritis(RP)and to improve early recognition for it.Methods Clinical and laboratory data of 56 patients with RP were analyzed retrospectively.Results Ratio of number of male patients to female ones was 1.2.Age at onset was(46?11)years(ranging from 27 to 71)and average interval between onset and diagnosis was(21? 35)months,(8?6),(16?31)and(29?37)months for patients initial onset with auricle,respiratory tract and joints involved,respectively.Site involved included airway in 40 patients(71.4%),auricle in 32 (57.1%),joints in 32(57.1%),eyes in 27(48.2%),nasal chondritis in 25(44.6%)and inner ear in 13(23.2%).At initial stage of the course,17 patients were misdiagnosed as respiratory infection (30.4%),nine as perichondritis(16.1%),six as pulmonary tuberculosis(10.7%),five as rheumatoid arthritis(8.9%).Seven of 40 patients with airway involvement received metallic stents for their tracheobronchial stenosis.Four patients whose condition never improved after regular therapy all had respiratory involvement.Conclusions Patients of RP with initial onset at non-auricle,non-nasal sites tended to be misdiagnosed.Prevalence of airway involvement was not so low with a poor prognosis in patients of RP.

OBJECTIVETo explore the effect of Chang'an No. I Recipe (CA) on 5-hydroxytryptamine signal system and mRNA expression levels of hippocampal brain derived neurotrophic factor (BDNF) in visceral hypersensitivity model rats with irritable bowel syndrome (IBS).

METHODSIBS visceral hypersensitivity rat models were established by combined chronic restraint stress and forced swimming. Successfully modeled rats were randomly divided into the model group, the Dicetelgroup (27 mg/kg) , the Fluoxetine group (3.6 mg/kg), the high dose CA group (22.6 mg/kg), the medium dose CA group (11.3 mg/kg), and the low dose CA group (5.7 mg/kg) according to body weight, 9 in each group. Besides, a normal control group with 10 rats was set up. Corresponding medication was administered to rats in each treatment group. Equal volume of physiological saline was administered to rats in the model group by gastrogavage. All medication was performed once per day for a total of 14 days. Pain threshold was determined by abdominal withdrawal reflex (AWR). Changes of colon 5-HT levels were determined by immunohistochemical assay. mRNA expression levels of hippocampal 5-hydroxytryptamine 1A receptor (5-HT1a) and BDNF were detected by immunofluorescent RT-PCR.

RESULTSCompared with the normal control group before treatment, pain threshold was obviously lowered in proctectasia rats of each group (P < 0.01). Compared with the normal control group after treatment, pain threshold was obviously lowered in rats of the model group; colon 5-HT levels, mRNA expression levels of hippocampal 5-HT1a and BDNF were obviously elevated (P < 0.01). Compared with the model group, pain threshold was obviously elevated in the Fluoxetine group and all CA groups; colon 5-HT levels were obviously reduced in the Dicetel group, high and medium dose CA groups (P < 0.05, P < 0.01); mRNA expression levels of hippocampal 5-HT1a and BDNF were obviously reduced in each CA group (P < 0.01); mRNA expression levels of hippocampal BDNF were obviously reduced in the Fluoxetine group (P < 0.01).

CONCLUSIONSThe target points of CA were involved in brain and gut. CA could reduce pain threshold of proctectasia rats, down-regulate colon mucosal 5-HT levels, and lower mRNA expression levels of BDNF and 5-HT1a in rat hippocampus.

Animals ; Brain-Derived Neurotrophic Factor ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Hippocampus ; Hypersensitivity ; Intestinal Mucosa ; Irritable Bowel Syndrome ; drug therapy ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Serotonin ; metabolism

Objective To evaluate the diagnostic values of the breast imaging reporting and data system-MRI (BI-RADS-MRI)description about non-masslike enhancement by data mining. Methods Fifty-five patients with non-masslike enhancement lesions showed on breast contrast-enhanced MRI were evaluated using two data mining algorithms (Logistic regression and decision tree) and 10-fold cross-validation methods. Results There were 28 malignant and 27 benign lesions. The most frequent findings of the malignant lesions were clustered ring enhancement and clumped enhancement [ 12 and 4 lesions, respectively; 84. 2% (16/19) in decision trees, partial regression coefficients in Logistic model were 2. 128 and 1.723, respectively], whereas homogenous, stippled, reticular internal and linear ductal enhancement were the most frequent findings in benign lesions [ 4、9、1 and 7 lesions, respectively; 72. 4% (21/29) in decision tree, partial regression coefficients in Logistic model were 0.357 (homogenous), 1. 861 (stippled) and 18. 870( reticular), respectively]. 10-fold cross-validation indicated that decision tree (C5.0) achieved an accuracy of 69.3% with a sensitivity of 66.7% and a specificity of 71.7% in comparison to the Logistic regression model with an accuracy of 57. 0%, a sensitivity of 43.3% and a specificity of 71.7%. Conclusions The diagnosis efficacy of non-masslike enhancement interpretation according to BI-RADS-MRI is not high. It is very important to find more potential features of non-masslike enhancement to improve the diagnosis accuracy.

Objective To study the immunogenicity of human embryonic stem cells(hESCs)and the derived neural stem cells(NSCs)in vitro.Methods The constitutive expression of human leucocyte antigen(HLA)Ⅰ and Ⅱ in hESCs and the NSCs derived from these hESCs were detected by flow cytometry (FCM), as well as the expression of HLA-Ⅰ,Ⅱin NSCs induced by 30 ng/ml recombination human interferon-?(IFN-?).Meanwhile, the NSCs before and after induction of IFN-? were co-cultured with peripheral blood lymphocyte obtained from healthy person.Lymphocyte proliferation standing for the immunoreactivity of NSCs was then investigated.Results The hESCs slightly expressed HLA-Ⅰ(6.18%) and hardly any HLA-Ⅱ before differentiation.However, the NSCs expressed more HLA-Ⅰ(23.56%)as well as HLA-Ⅱ(1.28%, 1.73%)than the hESCs did.Both HLA-Ⅰ(46.43%)and HLA-Ⅱ(8.73%, 10.57%)expressed by the NSCs after they were induced by IFN-? were up-regulated.Conclusions hESCs express certain level of HLA-Ⅰ molecules but do not constitutively express HLA-Ⅱ molecules.The derived NSCs express heavy HLA-Ⅰ and a little HLA-Ⅱ, when treated by IFN-? they can inducibly up- regulated both molecules.The NSCs derived from HESCs are of immunogenicity, which induce rejection aiming at HLA-Ⅰ molecules or even at HLA-Ⅱ molecules when the host is inflammative or under stress, which can result in a failure of cellular transplantation.