Objective Single voxel proton spectroscopy technique (1H-MRS)was performed in the healthy newborn brain tissue to investigate the metabolic ratio in the right basal ganglia and the right frontal lobe changes with gestational age, and to improve the understanding of the neonatal brain development. Methods In this study, 69 newborns were selected, including twenty-five premature and forty-four term neonates. By using the Gesell developmental scale to evaluate brain development , they all had normal neurologic outcomes at 12-months corrected age. A point-resolved spectroscopy sequence was used to study the metabolic data obtained from each region of interest. Results N-acetylaspartate: creatine and N-acetylaspartate:choline were positively correlated with gestational age (the right basal ganglia r = 0.27, 0.63, the right frontal lobe r = 0.44, 0.64 respectively, P < 0.05) and choline:creatine was negative (the right basal ganglia r = -0.51,the right frontal lobe r = -0.41, P < 0.05), with a linear regression relationship among variables. In the same gestational age group , the N-acetylaspartate: choline of the right basal ganglia was higher than that of the right frontal lobe , and the metabolic ratios among the anatomic locations were significantly different (P < 0.05). Conclusion Neonatal brain metabolite levels are associated with gestational age , and MRS can monitor newborn brain maturation quantitatively.

OBJECTIVETo explore the relationship between the relevant factors and prostate cancer among Hui and Han populations.

METHODSThe study involved 267 prostate cancer patients as cases (214 cases from Han population and 53 cases from Hui population) and 534 prostatic hyperplasia patients as controls (428 cases from Han population and 106 cases from Hui population). All the patients were collected from the General Hospital of Ningxia Medical University during January of 2007 to September of 2013. The level of fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), total prostate specific antigen (T-PSA), free prostate specific antigen (F-PSA) and free/total prostate specific antigen (F/T-PSA) were collected from the clinical medical records of the patients. Data were analyzed by the conditional logistic regression method, and attributable risk proportion(ARP) was calculated.

RESULTSIn Hui population, the risk of prostate cancer for drinkers was 20.48 times higher than the non-drinkers (35.8% (19/53) to 5.7% (6/106), OR = 20.48, 95% CI: 4.95-84.66). The high level of F-PSA significantly increased the risk of prostate cancer for Hui group (83.0% (44/53) to 55.7% (59/106), OR = 4.27, 95%CI: 1.18-15.43). In contrast, the high TG level decreased the risk of prostate cancer for Hui group (18.9% (10/53) to 20.8% (22/106), OR = 0.24, 95% CI: 0.07-0.83). In Han population, the risk of prostate cancer for smokers was 1.89 times higher than the non-smokers (55.1% (118/214) to 39.7% (170/428), OR = 1.89, 95% CI: 1.28-2.78). Either high level of T-PSA or F-PSA increased the risk of prostate cancer for Han group (86.4% (185/214) to 53.7% (230/428),OR = 2.34, 95%CI:1.22-4.52;85.5% (183/214) to 56.1% (240/428), OR = 2.43, 95% CI:1.29-4.59). However, the high TG level or high ratio of F/T-PSA decreased the risk of prostate cancer (15.4% (33/214) to 18.7% (80/428), OR = 0.59, 95% CI:0.36-0.98; 53.3% (114/214) to 73.4% (314/428), OR = 0.53, 95% CI:0.36-0.78). The APRs of drinking and high level of F-PSA in Han populations were 66.6%, 62.4% in Hui populations , and the APRs of smoking and high level of T-PSA, high level of F-PSA were 33.8%, 71.3%, 67.3% in Han populations.

CONCLUSIONBoth drinking and high level of F-PSA might be the risky factors of prostate cancer while the high TG level might be protective factor for Hui group. However, for Han population, smoking, high T-PSA level, and high F-PSA level might be risky factors for prostate cancer while the high TG level and high ratio of F/T-PSA might be protective factors. In summary, the clinical relevant factors of prostate cancer may play different roles between Hui and Han populations in Ningxia region.

Alcoholic Beverages ; Biopsy ; Case-Control Studies ; China ; Humans ; Male ; Prostate-Specific Antigen ; Prostatic Neoplasms ; ethnology ; Risk Factors ; Smoking ; Triglycerides

Objective : To explore the effects of Er: YAG laser irrigation technology on smear layer removal and dentin microhardness. Methods : A total of 102 ex vivo premolars were selected to amputate the crown , leaving a root length of 13 mm , after mechanical preparation , there were divided into experimental group (3% sodium hypochlorite , 3% NaOCl) and control group (0. 9% sodium chloride solution , NS) , and received syringe , ultrasound and Er: YAG laser terminal irrigation , which were specifically grouped into NaOCl + syringe , NaOCl + ultrasound , NaOCl + laser, NS + syringe , NS + ultrasound and NS + laser groups ( n = 17 ) . Scanning electron microscopy (SEM) evaluated smear layer removal from the upper, middle and apical parts of the root. The Vickers microhardness tester measured the microhardness before and after irrigation. Results : The NaOCl + laser group had the best effect on removing the root canal smear layer, and the amplitude of reducing the microhardness of dentin was the largest. There was no significant difference in the reduction of microhardness compared with the NaOCl + ultrasonic group (P > 0. 05) . Conclusion Er: YAG laser⁃activated NaOCl solution improves the clearance of the smear layer and reduced the microhardness of dentin.

Objective : To investigate the effects of different occlusal veneer preparation designs and fiber posts on the fracture load and failure mode of endodontically treated maxillary premolars with pulp-piercing wedge-shaped defect． Methods : 60 maxillary first premolars were randomly divided into group A and group B after Root Canal Therapy (RCT) and severe defects(n = 30) ．Group A was filled with glass fiber post and resin core，and group B was filled with resin core only．Then the occlusal veneer( G2) ，buccal-occlusal veneer( G3) and buccal-proximal-occlusal veneer ( G4 ) were applied to the isolated teeth．The teeth filled with composite resin ( G1 ) and full crown ( G5) were set as negative and positive control respectively，with 6 samples in each group．The sample was subjected to 5 000 hot and cold cycles and 20 000 vertical compression load aging．Finally，all the samples were loaded with static load until the sample broke at the speed of 0．5mm / min．The fracture load and failure mode of each sample were recorded. Results : Both the fracture load in group A and B was G5 ＞G3 ＞G2 ＞G4 ＞G1，and the fracture load in G2，G3，G4，G5 was significantly higher than that in G1 (P＜0. 05) ，and there was no significant difference between group A and B (P＞0. 05) ．The fracture form of G3 was mostly unbonding of the repair body，which was conducive to re-repair． Conclusion Buccal ( occlusal) veneer is the most effective in repairing pulp-piercing wedge-shaped defects．The fiber post could not significantly enhance the fracture load of the pulp-piercing wedge- shaped defects teeth.