OBJECTIVEThe purpose of this study is to compare the fracture strengths of custom-fabricated Celay all-ceramic post-core, custom cast metal post-core, and prefabricated stainless steel post (Parapost) plus composite resin core with or without a 2.0 mm dentine ferrule.

METHODSA total of 60 recently extracted human maxillary central incisors were endodontically treated and divided into five groups of 12. They were given the following treatments: Group A: Celay ceramic post-core with 2.0 mm dentine ferrule, Group B: Celay ceramic post-core with no dentine ferrule, Group C: cast metal post-core with 2.0 mm dentine ferrule, Group D: cast metal post-core with no dentine ferrule, and Group E: prefabricated post and composite core with 2.0 mm dentine ferrule. All specimens were stored at 100% humidity at room temperature for 30 days before testing. Each specimen was in a special jig at a 45 degrees angle to the long axis and subjected to a load on MTS 810 universal material testing machine until failure, with crosshead speed of 0.02 cm/min. Analysis of variance followed by the Newman-Keuls pairwise multiple comparison test was used to compare the results of the groups tested.

RESULTSThere was a statistically significant difference between five groups (P < 0.01). Celay ceramic post-core with 2.0 mm dentine ferrule (758.35 N +/- 119.26 N) and cast metal post-core with 2.0 mm dentine ferrule (756.63 N +/- 166.22 N) had a significantly larger mean failure threshold for fracture than the other three groups which had no significant difference between each other. There was a statistically significant difference between the fracture resistance of Celay post-core restored teeth with and without 2.0 mm dentine ferrule.

CONCLUSIONThe custom-fabricated Celay post-core could be a choice for clinical use in endodontically treated tooth when the final restoration is an all-ceramic crown and the preparation has a 2.0 mm dentine ferrule.

Ceramics ; Crowns ; Dental Porcelain ; chemistry ; Dental Restoration Failure ; Humans ; Incisor ; Inlays ; Materials Testing ; Post and Core Technique ; Stress, Mechanical ; Tooth Fractures ; prevention & control

Objective: To explore the mediating effect of self-efficacy for exercise on social support and kinesiophobia in patients with rheumatoid arthritis (RA), so as to provide insights into alleviating fear for exercise and formulating exercise intervention programs. Methods: RA patients hospitalized in a tertiary hospital in Harbin City from June to December 2023 were selected, and the levels of kinesiophobia, self-efficacy for exercise and social support were investigated using the Tampa Scale of Kinesiophobia (Chinese version), the Self-Efficacy for Exercise and the Social Support Rating Scale, respectively. The mediating effect of self-efficacy for exercise on social support and kinesiophobia was examined using a structural equation model. Results: A total of 216 people were investigated, including 45 males (20.83%) and 171 females (79.17%), with the median age of 54.00 (interquartile range, 13.75) years. There were 159 of patients living in the urban areas, accounting for 73.61%. There were 102 of patients with a disease course of 1 to 5 years, accounting for 47.22%. The median scores of kinesiophobia, self-efficacy for exercise and social support were 31.00 (interquartile range, 5.00), 5.00 (interquartile range, 2.00) and 39.50 (interquartile range, 17.00), respectively. Social support had a direct negative effect on kinesiophobia (effect value=-0.358, P<0.05) and a indirect negative effect on kinesiophobia through self-efficacy for exercise (effect value=-0.887, P<0.05), and the mediating effect contributed 93.86% to the total effect. Conclusion Social support can directly or indirectly influence kinesiophobia through self-efficacy for exercise among patients with RA.

OBJECTIVETo investigate the influence of post-core structure on the strength of endodontically treated and crowned teeth with or without a 2.0 mm dentine ferrule.

METHODSA total of 60 recently extracted human maxillary central incisors were endodontically treated and randomly divided into five groups of 12. They were given following treatments: Group A, endodontically treated; Group B, endodontically treated and crowned (PFM); Group C, cast metal post-core with 2.0 mm dentine ferrule and crowned (PFM); Group D, cast metal post-core with no dentine ferrule and crowned (PFM); Group E, prefabricated post and composite core with 2.0 mm dentine ferrule and crowned (PFM). All specimens were stored at 100% humidity at room temperature for 30 days before testing. Each specimen was in a special jig on the MTS 810 universal material testing machine and subjected to a load at a 135-degree angle to the long axis until failure, with crosshead speed of 0.02 cm/minute. Analysis of variance followed by the Newman-Keuls pairwise multiple comparison tests was used to compare the results.

RESULTSThere was a statistically significant difference between different restorative methods. The cast metal post-core with 2.0 mm dentine ferrule and crowned teeth had the highest fracture strength (1793.59 +/- 387.93N), followed by endodontically treated intact teeth (1466.68 +/- 240.11N). No significant difference in the fracture strength was found among the other three groups (958.49 +/- 286.02N; 992.98 +/- 291.00N; 994.94 +/- 285.04 N). There was a statistically significant difference in the fracture resistance between crowned teeth with and without 2.0 mm dentine ferrule (P < 0.01).

CONCLUSIONSNot all post-core structure could improve the strength of endodontically treated teeth. The dentine ferrule can effectively improve the fracture resistance of endodontically treated and crowned teeth.

Biomechanical Phenomena ; Crowns ; Humans ; Stress, Mechanical ; Tooth, Nonvital

Objective To investigate the role of the percentage of the total cross-sectional area of small pulmonary vessels for the lung area (%CSA) from multi-slice CT (MSCT) in evaluating the severity of chronic obstructive pulmonary disease (COPD). Methods One hundred and sixty-six COPD patients and 166 normal subjects underwent chest MSCT scans and all data were analyzed retrospectively. COPD patients underwent pulmonary function tests (PFT), including forced expiratory volume in one second (FEV1%) and FEV1/forced vital capacity (FEV1/FVC), and were classified into mild (n=32), moderate (n=65), severe (n=69) groups according to pulmonary function results, respectively. The%CSA less than 5 mm2 and 5—10 mm2 for the lung area (%CSA<5 and %CSA5-10) of small pulmonary vessels were measured with Image J image-processing program. Comparison of%CSA<5 and%CSA5-10 between the COPD and control groups was perfomred using t test, and the comparison between the 3 COPD subgroups and control group were carried out using ANOVA test. The correlation between %CSA and PFT was evaluated by the Spearman rank correlation test. The sensitivity and specificity of %CSA to diagnose COPD and the best cutoff were calculated from areas under the ROC curves. Results %CSA<5 of COPD patients and control group were (0.56 ± 0.19)%and (0.82 ± 0.15)%(t=12.80, P<0.001), respectively.%CSA5-10 of the two groups were (0.19 ± 0.09)%and (0.33 ± 0.16)%(t=8.93,P<0.001), respectively. The AUC values of%CSA<5 and%CSA5-10 were 0.866 and 0.790, respectively. When the cut-off values of%CSA<5 and%CSA5-10 were 0.65%and 0.24%, the sensitivities and specificities were 88%and 71%, 76%and 81%, respectively. The mean values of%CSA<5 in mild, moderate and severe groups were (0.67±0.20)%, (0.61±0.16)%and (0.44±0.14)%, respectively (P<0.05). The mean values of %CSA5-10 in the three groups were (0.19 ± 0.06)%, (0.19 ± 0.10)% and (0.20 ± 0.08)%, respectively.%CSA5-10 in the three groups were of no significant difference (P>0.05). FEV1%and FEV1/FVC in COPD patients were (60.38±15.52)%and 57.95±22.27.%CSA<5 in COPD patients correlated positively with both FEV1%and FEV1/FVC (r=0.609 and 0.721, P<0.01, respectively).%CSA5-10 in COPD patients correlated positively with both FEV1%and FEV1/FVC (r=0.271 and 0.288, P<0.01, respectively). Conclusion The measurement of%CSA<5 and%CSA5-10 in MSCT images correlated with PFTs and%CSA<5, which may play an important role in evaluating the severity of COPD.

Objective To discuss the significance and value of speckle tracking imaging (STI) technique for accurate evaluating different types myocardial systole. Methods Anterior interventricular branches of 11 healthy crossbreed dogs were separated and ligatured to establish acute myocardial infarction models. The short axle radial strain (RS), circumferential strain (CS) of ventricular sinister and long axle longitudinal (LS) of apex of experiment dogs were measured with STI technique before and after myocardial infarction. Results Before myocardial infarction, no statistical difference of RS, CS was detected among sections of left ventricle (P>0.05), and RS was greater than LS (P<0.05). When detector was at the apex of base, LS of middle, apex sections of left ventricle myocardium increased gradually (LS of base section was least and apex section was most) (P<0.05). RS, CS and LS of antetheca, forepart of interventricular septum of middle of left ventricle and antetheca, posterior and forepart septum of apex all became lower after myocardial infarction (P<0.05). Conclusion Strains caused by all types of myocardium action can be accurately evaluated with STI.

Objective To investigate the relationship between sleep duration and obesity, and the risk of common chronic diseases in the occupational population in Shanghai City. Methods A total of 18 775 occupational individuals were selected as the study subjects using convenience sampling method in Shanghai City. Data on personal lifestyle behaviors and medical examination results were collected. The relationship between sleep duration and different types of obesity with dyslipidemia, hyperuricemia, hypertension, and hyperglycemia was analyzed. Results The incidence of dyslipidemia, hyperuricemia, hypertension, and hyperglycemia among the study subjects was 24.9%, 16.2%, 11.5%, and 7.3%, respectively. The incidence of these four chronic diseases were higher in individuals with central obesity and suboptimal sleep compared to the control group (all P<0.01). Multivariate logistic regression analysis showed that suboptimal sleep combined with general obesity/overweight increased the risk of dyslipidemia, hyperuricemia, hypertension, and hyperglycemia in the study subjects ［odds ratio (OR) were 2.40, 3.47, 3.30, and 2.79, respectively; all P<0.01］, after adjusting for age, gender, education level, marital status, occupation type, labor intensity, smoking, and drinking. Suboptimal sleep combined with central obesity also potentially increased the risk of these four chronic diseases (OR were 2.25, 3.09, 3.09, and 2.98, respectively; all P<0.01). Conclusion The incidence of common chronic diseases is relatively high in the occupational population in Shanghai City. Suboptimal sleep combined with different types of obesity increases the risk of common chronic diseases.

A 1 270 bp full-length cDNA fragment was obtained from the Schistosoma japonicum (Chinese strain) adult cDNA library after the '3' and 5' ends of the incomplete expression sequence tag (EST) of hypoxanthine-guanine phosphoribosyltransferase of Schistosoma japonicum (SjHGPRT) were amplified by the anchored PCR with 2 pairs of primer that were designed according to the published incomplete SjHGPRT EST and the sequence of multiclone sites of library λgt1 1 vector. Sequence analysis indicated that this fragment, with an identity of 82% to hypoxanthine-guanine phosphoribosyltransferase ofSchistosoma mansoni (SmHGPRT), contained a complete open reading frame(ORF). The deduced amino acid sequence showed 83% identity to that of SmHGPRT. This fragment was cloned into the prokaryotic expression vector pQE30, and subsequently sequenced and expressed in Escherichia coli. SDS-PAGE revealed that M of the recombinant protein was about 28 ku. Western-blot analysis showed that the recombinant protein was recognized by the polyclonal antisera from rabbits immunized with Schistosoma japonicum adult worm antigen. Mice vaccinated with recombinant protein revealed significant worm burden, liver eggs per gram (LEPG), fecal eggs per gram (FEPG) and intrauterine eggs of the female worms reduction percentage, compared with the controls. Taken together, the SjHGPRT full-length cDNA can be cloned and expressed in E. coli as a recombinant protein that elicited immunity against the challenge infection with Schistosoma japonicum, indicating its potential as a partia1 protection vaccine candidate.

A 1 270 bp full-length cDNA fragment was obtained from the Schistosoma japonicum (Chinese strain) adult cDNA library after the 3′ and 5′ ends of the incomplete expression sequence tag (EST) of hypoxanthine-guanine phosphoribosyltransferase of Schistosoma japonicum (SjHGPRT) were amplified by the anchored PCR with 2 pairs of primer that were designed according to the published incomplete SjHGPRT EST and the sequence of multiclone sites of library ?gt11 vector. Sequence analysis indicated that this fragment, with an identity of 82% to hypoxanthine-guanine phosphoribosyltransferase of Schistosoma mansoni (SmHGPRT), contained a complete open reading frame(ORF). The deduced amino acid sequence showed 83% identity to that of SmHGPRT. This fragment was cloned into the prokaryotic expression vector pQE30, and subsequently sequenced and expressed in Escherichia coli. SDS-PAGE revealed that M of the recombinant protein was about 28 ku. Western-blot analysis showed that the recombinant protein was recognized by the polyclonal antisera from rabbits immunized with Schistosoma japonicum adult worm antigen. Mice vaccinated with recombinant protein revealed significant worm burden, liver eggs per gram (LEPG), fecal eggs per gram (FEPG) and intrauterine eggs of the female worms reduction percentage, compared with the controls. Taken together, the SjHGPRT full-length cDNA can be cloned and expressed in E.coli as a recombinant protein that elicited immunity against the challenge infection with Schistosoma japonicum, indicating its potential as a partial protection vaccine candidate.

Objective:To develop a questionnaire on knowledge, attitude and practice of Helicobacter pylori (Hp) infection among physical examination population, and to verify its reliability and validity.Methods:This study was a cross-sectional survey. Based on the theory of knowledge, attitude and practice, the first draft of the questionnaire on knowledge, attitude and practice of Hp infection in physical examination population was designed by means of retrospective literature research, qualitative interview, discussion in the research group. The structure and items of the questionnaire were consulted and revised by the expert consultation method (Delphi method). Through pre investigation of 186 physical examination personnel from May to June in 2021, the final version of the "knowledge, attitude and practice questionnaire on Helicobacter pylori infection among physical examination population" was formed after adjustment and verification of the reliability and validity of the questionnaire.Results:The questionnaire of knowledge, attitude and practice of Hp infection in physical examination population included 3 dimensions and 28 items, and the cumulative variance contribution rate was 56.271%. The content validity index of each item level of the questionnaire was 0.75-1.00, and the content validity index of the total questionnaire was 0.94. The Cronbach alpha of knowledge, attitude and practice dimensions in this questionnaire were 0.862, 0.901 and 0.798 respectively. The overall Cronbach alpha of the questionnaire was 0.890, and the half reliability was 0.698. The test-retest reliability of the questionnaire was 0.919, and the test-retest reliability of each dimension was 0.924, 0.917 and 0.845.Conclusions:The questionnaire has good reliability and validity, and can be used to measure the level of knowledge, attitude and practice of Hp infection in physical examination population.

Objective To investigate the risk factors associated with necrosis in interstitial oedematous pancreatitis(IOP)and to develop a nomogram model for the early prediction of necrosis in IOP.Methods A retrospective analysis was conducted on 306 patients diagnosed with IOP.Patients were stratified into necrosis and edema groups based on the presence or absence of pancreatic necrosis through follow-up CT-enhanced examinations.Logistic regression analysis was employed to identify independent predictive factors for necrosis in IOP.Subsequently,a nomogram model was developed,and its discriminative ability,accuracy,and practicality were assessed through receiver operating characteristic(ROC)curve,calibration curve,and decision curve analysis(DCA).Results Balthazar computed tomography severity index(CTSI),gender,lactate dehydrogenase(LDH),and triglyceride(TG)were finally identified as four independent predictors for constructing the nomogram model.The area under the curve(AUC)of the nomogram model was 0.800[95％confidence interval(CI)0.731-0.869].The calibration curve indicated good consistency between the predicted probabil-ity and the actual probability of necrosis in IOP(P=0.737).DCA suggested high practicality of the nomogram model within the threshold probability range of 3％to 66％and 75％to 96％.Conclusion The nomogram model based on Balthazar CTSI,gender,LDH,and TG demonstrates good efficacy in early prediction of necrosis in IOP.