OBJECTIVETo establish objectively biomechanical criteria for temporomandibular joint disc tissue engineerings.

METHODSEight temporomandibular joint discs from a four-month-old goat were separated completely. A cylindrical sample with diameter of 3 mm in the anterior, intermediate, and posterior bands was obtained, and the samples underwent pre-compression test with three cycles under a speed of 0.025 mm · s⁻¹. With the end condition for the maximum load of less than 4.9 N and 1.5 mm compression displacement, the formal compression test was performed with the same speed. Moreover, this test obtained the stress-strain relationship and elastic modulus of each disc band. Ultrastructure and collagen fiber orientation of the district zone were observed by scanning electron microscope and polarized light microscope.

RESULTS1) The physiological strain range of an articular disc was within 10%, and the quasilinear constitutive equation of articular disc tissues can be fitted with the polynomial function: y = ax + bx² + cx³. 2) The elastic modulus of the intermediate disc zone was the largest (P < 0.05). No significant difference existed between the anterior and posterior bands (P = 0.361). 3) Scanning electron microscope and polarized light microscope showed an annular disc collagen network structure, which was the internal part of the goat temporomandibular joint disc. The collagen arrangement of intermediate bands was tensely arranged anterior-posteriorly. The collagen of anterior and posterior bands went through mediolaterally with intersection of anterior-posterior branch fibersd.

CONCLUSIONAnnular collagen network structure is the basis for goat temporomandibular joint disc compression resistance properties. The intermediate band demonstrated higher compression resistance performance than the anterior and posterior bands.

Animals ; Biomechanical Phenomena ; Collagen ; Elastic Modulus ; Extracellular Matrix ; Goats ; Temporomandibular Joint Disc ; Tissue Engineering

Objective To investigate the MR signal intensity and spectroscopy characteristics of lumbar bone marrow in normal adult of Tibetan and Han nationality in high altitude.Methods According to the inclusion criteria,lumbar MRI examinations in Tibetan and Chinese volunteers(each 50 cases)were obtained.For each inspector,the lumbar 3 vertebra was selected,TFE sequence was used to measure the signal strength,T2map was used to measured the T2time,and 1H-MRS was used to measure the lumbar bone marrow spectrum signal.The measured data were statistically analyzed.Results Compared with the Han nationality in Xining area,T1-TFE sequence of Tibetan showed obvious low signal in the lumbar vertebra.The relative signal intensity were significantly different(P=0.001).For measurement of T2time,there was no significant differences(P=0.061).The spectrum analysis showed a line of low fat high water for Tibetan,and a line of low water high fat for Han nationality in Xining area.There were significant differences for water peak intensity,Width, Height and peak Area,but no significant differences in Lipid peak.There were significant differences(P<0.05)on Lipid water absorption ratio, fat water ratio,fat fraction between the two groups.Conclusion The Tibetan shows a low signal on T1WI sequence of lumbar spine which is considered in hypoxia condition for a long time,and the bone marrow red pulp associated with water content increased sig-nificantly.

Objective:To compare the different optimized anesthesia strategies in pediatric patients undergoing hypospadias surgery.Methods:Ninety pediatric patients with distal hypospadias undergoing Duckett operation, of American Society of Anesthesiologists physical status Ⅰor Ⅱ, aged 1-6 yr, weighing 10-25 kg, were divided into 3 groups ( n=30 each) using a random number table method: caudal block combined with general anesthesia group (group CG), neurostimulator-guided pudendal nerve block combined with general anesthesia group (group PG) and ultrasound-guided dorsal penile nerve block combined with general anesthesia group (group DPG). Anesthesia was induced with propofol-fentanyl, patients were ventilated through the laryngeal mask and maintained spontaneous breathing, and anesthesia was maintained with sevoflurane.The corresponding regional block was performed in each group, and block was performed with 0.25% ropivacaine 1, 0.25 and 0.15 ml/kg in CG, PG and DPG groups, respectively.The consumption of ropivacaine, occurrence of insufficient analgesia during operation, emergence time, duration of post-anesthesia care unit stay, time of the first requirement for analgesics, requirement for analgesics within 24 h after operation, occurrence of postoperative agitation, nausea and vomiting and lower extremity motor block, and patients′ satisfaction score at 24 h after operation were recorded. Results:Compared with group CG, the consumption of ropivacaine was significantly reduced, the time of the first requirement for analgesics was prolonged, the postoperative requirement for analgesics was decreased, duration of post-anesthesia care unit stay was shortened, the incidence of lower extremity motor block was decreased, and patients′ satisfaction score was increased in group PG and group DPG, and the incidence of nausea and vomiting was decreased in group DPG ( P<0.05). Compared with group PG, the consumption of ropivacaine was significantly reduced, and the time of the first requirement for analgesics was shortened in group DPG ( P<0.05). There was no significant difference in the incidence of insufficient analgesia during operation (3% in group DPG) and incidence of postoperative agitation among the three groups ( P>0.05). Conclusion:Ultrasound-guided dorsal penile nerve block combined with general anesthesia provides significant efficacy with a higher safety, and the efficacy is better than that of caudal block combined with general anesthesia and neurostimulator-guided pudendal nerve block general anesthesia when used for pediatric patients undergoing hypospadias surgery.

To establish objectively biomechanical criteria for temporomandibular joint disc tissue engineerings. Methods Eight temporomandibular joint discs from a four-month-old goat were separated completely. A cylindrical sample with diameter of 3 mm in the anterior, intermediate, and posterior bands was obtained, and the samples underwent pre-compression test with three cycles under a speed of 0.025 mm·s?1. With the end condition for the maximum load of less than 4.9 N and 1.5 mm compression displacement, the formal compression test was performed with the same speed. Moreover, this test obtained the stress–strain relationship and elastic modulus of each disc band. Ultrastructure and collagen fiber orientation of the district zone were observed by scanning electron microscope and polarized light microscope. Results 1) The physiological strain range of an articular disc was within 10%, and the quasilinear constitutive equation of articular disc tissues can be fitted with the polynomial function: y=ax+bx2+cx3. 2) The elastic modulus of the intermediate disc zone was the largest (P<0.05). No significant difference existed between the anterior and posterior bands (P=0.361). 3) Scanning electron microscope and polarized light microscope showed an annular disc collagen network structure, which was the internal part of the goat temporomandibular joint disc. The collagen arrangement of intermediate bands was tensely arranged anterior–posteriorly. The collagen of anterior and posterior bands went through mediolaterally with intersection of anterior-posterior branch fibersd. Conclusion Annular collagen network structure is the basis for goat temporomandibular joint disc compression resistance properties. The intermediate band demonstrated higher compression resistance performance than the anterior and posterior bands.

Objective:To explore the diagnostic value of improved 18F-prostate specific membrane antigen (PSMA)-1007 PET-CT score (referred to as PSMA score) and multi parameter magnetic resonance imaging (mpMRI) prostate imaging reporting and data system (PI-RADS) score (referred to as PI-RADS score) for primary prostate cancer (PCa). Methods:A retrospective case series study was conducted. The imaging and clinical data of 134 suspected PCa patients underwent 18F-PSMA-1007 PET-CT and mpMRI examinations at Shanxi Province Cancer Hospital from July 2018 to May 2023 were collected. Pathological diagnosis showed 92 cases of PCa and 42 cases of benign prostatic lesions. The clinical and imaging parameters, as well as the distribution of patients with two scores, were compared between the two groups. The blind diagnosis of benign and malignant lesions was made based on the improved PSMA score (dividing 1 point into 1a and 1b points, 1b, 2 and 3 points were diagnosed as PCa), PI-RADS score (3, 4 and 5 points were diagnosed as PCa) and the combination of the two (diagnosed as PCa when either PSMA score ≥ 1b point or PI-RADS score ≥ 4 points was met). The indicators of the diagnostic efficiency of PSMA score, PI-RADS score and the combination of the two for PCa were calculated. Using pathological results as the gold standard, the receiver operating characteristic (ROC) curve of PSMA score, PI-RADS score and the combination of the two for diagnosing PCa was drawn, and the diagnostic efficiency of the 3 methods was analyzed. Results:The age, serum prostate-specific antigen, and maximum standard uptake value of PET-CT in the PCa group were higher than those in the benign prostatic lesion group, and the differences were statistically significant (all P < 0.05). The sensitivity, specificity, accuracy, false negative rate, false positive rate, positive predictive value, and negative predictive value of PSMA score for diagnosing PCa were 91.30% (84/92), 80.95% (34/42), 88.06% (118/134), 8.70% (8/92), 19.05% (8/42), 91.30% (84/92), and 80.95% (34/42), respectively; those of PI-RADS score were 93.48% (86/92), 61.90% (26/42), 83.58% (112/134), 61.90% (26/42), 38.10% (16/42), 84.31% (86/102), and 81.25% (26/32), respectively; those of the combination of the two were 97.83% (90/92), 88.10% (37/42), 94.78% (127/134), 2.17% (2/92), 11.90% (5/42), 94.74% (90/95), and 94.87% (37/39), respectively. The differences in specificity, accuracy, false negative rate, and false positive rate among the 3 methods were statistically significant (all P < 0.05). ROC curve analysis showed that the area under the curve of PSMA score, PI-RADS score and the combination of the two for diagnosing PCa were 0.930 (95% CI: 0.872-0.967), 0.935 (95% CI: 0.826-0.939) and 0.959 (95% CI: 0.910-0.986), respectively, and the differences between each two methods were statistically significant (all P < 0.05); the sensitivity of PSMA score, PI-RADS score and the combination of the two was 90.11%, 89.13% and 98.09%, and the specificity was 90.48%, 90.48% and 92.09%. Conclusions:Compared with the PI-RADS score, the improved PSMA score can improve the specificity and accuracy of PCa diagnosis, and decrease the false negative and false positive rates; the diagnostic efficiency of the combination of the two is superior.