Objective: To investigate the chemical constituents of Blaps rynchopetera. Methods: Compounds were isolated and purified on silica gel, Sephadex LH20, ODS, and D101 column chromtography. The structures were elucidated on the basis of NMR spectral data and HR-ESI-MS. Results: Ten cyclodipeptides were isolated from the n-butyl extract fraction of B. rynchopetera, and their structures were determined as cyclo (Leu-Pro) (1), cyclo (Val-Pro) (2), cyclo (Ile-Pro) (3), cyclo (Ser-Pro) (4), cyclo (Tyr-Pro) (5), cyclo (Val-Ile) (6), cyclo (Val-Leu) (7), cyclo (Val-Tyr) (8), cyclo (Ile-Tyr) (9), and cyclo (Phe-Tyr) (10). Conclusion: All the 10 compounds are isolated from B. rynchopetera for the first time.

Objective: To study the relations between neck/shoulder or low back pain and their daily behavioral habits among middle school students in Shenzhen. Methods: We randomly chose 3 952 students from 10 high schools in Shenzhen to complete the questionnaires. Data was gathered and analyzed, using the IBM SPSS 23.0. Results: Of the 3 952 participants, 20.3% had neck/shoulder pain and 15.2% had low back pain. Among students experienced neck/shoulder pain, female (25.3%), high school (24.5%) and boarding students (24.4%) experienced higher rates of neck/shoulder pain (P<0.05). Female students (17.9%) also had higher rate of low back pain (P<0.05). Results from logistic regression analysis showed that factors as: gender, type of school, taking naps on the desk, staying up late, self-perceived stress from learning, overloading homework, time spent on mobile phone and TV, spending long time on computer etc. were related to the neck/shoulder pain (P<0.05). Factors as: gender, naps on the desk, stay up late, self-perceived stress, overloading homework, time spent on mobile phone and TV etc., were related to low back pain (P<0.05). Conclusion: Neck/shoulder pain and low back pain were both commonly seen while high self-perceived stress, sedentary behaviors and poor sleeping habits were associated with both neck/shoulder and low back pain in high school students in Shenzhen.
Female ; Habits ; Humans ; Low Back Pain ; Neck Pain ; Risk Factors ; Schools ; Shoulder ; Shoulder Pain ; Sleep ; Students ; Surveys and Questionnaires

According to the hardware characters of the high intensive focused ultrasound (HIFU) serial-parallel robots, this paper presents an algorithm of 2-grade interpolation scheme which includes the rough and fine interpolations. Both pre-acceleration and post-acceleration are employed to meet the restrictive requirements of coordinated dynamic performance and the detailed procedure of the interpolation algorithm is given too.
Algorithms ; Artificial Intelligence ; Computer Simulation ; Equipment Design ; Humans ; Robotics ; Ultrasound, High-Intensity Focused, Transrectal ; instrumentation ; methods

From the chloroform extracts of the dried Folium Microcos, four compounds were isolated by using repeated column chromatography on silica gel and recrystallization and their structures were elucidated by physicochemical properties and UV, MS and NMR, separately. They are N-methyl-6alpha-(deca-1', 3', 5'-trienyl)-3beta-methoxy-2beta-methylpiperidine, 6-(deca-1', 3', 5'-trienyl)-3-methoxy-2-methylpiperidine, N-methyl-6-(deca-1', 3', 5'-trienyl)-2, 3-dimethylpiperidine and N-methyl-6-(deca-1', 3', 5'-trienyl)-2-methylpiperidine, named as micropiperidine A, micropiperidine B, micropiperidine C and micropiperidine D, respectively. The latter three are new compounds.
Alkaloids ; chemistry ; isolation & purification ; Molecular Structure ; Piperidines ; chemistry ; isolation & purification ; Plant Leaves ; chemistry ; Plants, Medicinal ; chemistry ; Tiliaceae ; chemistry

OBJECTIVETo investigate the microstructure and mechanical properties of a new IPS-Empress 2 dental glass-ceramic.

METHODSAFM, SEM and XRD were used to analyze the microstructure and crystal phase of IPS-Empress 2 glass-ceramic. The flexural strength and fracture toughness were tested using 3-point bending method and indentation method respectively.

RESULTSIPS-Empress 2 glass-ceramic mainly consisted of lithium disilicate crystal, lithium phosphate and glass matrix, which formed a continuous interlocking structure. The crystal phases were not changed before and after hot-pressed treatment. AFM showed nucleating agent particles of different sizes distributed on the highly polished ceramic surface. The strength and fracture toughness were 300 MPa and 3.1 MPam(1/2).

CONCLUSIONThe high strength and fracture toughness of IPS-Empress 2 glass ceramic are attributed to the fine lithium disilicate crystalline, interlocking microstructure and crack deflection.

Aluminum Silicates ; chemistry ; Compressive Strength ; Dental Porcelain ; chemistry ; Materials Testing ; Microscopy, Electron, Scanning ; Tensile Strength ; X-Ray Diffraction

BACKGROUND/AIMS: Neurotensin is a gut-brain peptide with both inhibitory and excitatory actions on the colonic musculature; our objective was to understand the implications of this for motor patterns occurring in the intact colon of the rat. METHODS: The effects of neurotensin with concentrations ranging from 0.1-100 nM were studied in the intact rat colon in vitro, by investigating spatio-temporal maps created from video recordings of colonic motility before and after neurotensin. RESULTS: Low concentration of neurotensin (0.1-1 nM) inhibited propagating long distance contractions and rhythmic propagating motor complexes; in its place a slow propagating rhythmic segmental motor pattern developed. The neurotensin receptor 1 antagonist SR-48692 prevented the development of the segmental motor pattern. Higher concentrations of neurotensin (10 nM and 100 nM) were capable of restoring long distance contraction activity and inhibiting the segmental activity. The slow propagating segmental contraction showed a rhythmic contraction—relaxation cycle at the slow wave frequency originating from the interstitial cells of Cajal associated with the myenteric plexus pacemaker. High concentrations given without prior additions of low concentrations did not evoke the segmental motor pattern. These actions occurred when neurotensin was given in the bath solution or intraluminally. The segmental motor pattern evoked by neurotensin was inhibited by the neural conduction blocker lidocaine. CONCLUSIONS: Neurotensin (0.1-1 nM) inhibits the dominant propulsive motor patterns of the colon and a distinct motor pattern of rhythmic slow propagating segmental contractions develops. This motor pattern has the hallmarks of haustral boundary contractions.
Absorption ; Animals ; Baths ; Colon* ; In Vitro Techniques ; Interstitial Cells of Cajal ; Lidocaine ; Myenteric Plexus ; Neural Conduction ; Neurotensin* ; Peristalsis ; Rats* ; Receptors, Neurotensin ; Video Recording

OBJECTIVETo evaluate the differences in clinicopathological characteristics and severity between American and Chinese patients with colorectal Crohn disease(CD).

METHODSBetween March 1985 and September 2004, 68 patients with colorectal CD in Cleveland Clinic Florida (America) and 85 patients with colorectal CD in the 301 Hospital(China) were enrolled in the study. Data of two groups,including demographics, clinical characteristics, extraintestinal manifestations, presenting symptoms, location and pathological characteristics,were compared.

RESULTS60.3% of American patients and 36.5% of Chinese patients were female(P=0.003). 11.8% of American patients and 1.2% of Chinese patients had a family history of CD(P=0.016). American patients had a significantly higher rate of extraintestinal disease (39.7% vs 20.0%), abscess(19.0% vs 0), and anorectal fistulas(51.5% vs 0). American patients had significantly more extensive disease than Chinese patients(pancolitis: 44.1% vs 4.7%, P<0.01). American patients had a significantly higher rate of disease involving the ascending colon, transverse colon, descending colon, sigmoid colon, anorectal area compared with Chinese patients(all P<0.05).

CONCLUSIONSAmerican patients with colorectal Crohn disease seem to have a female predominance, a higher rate of CD family history, to involve the distal intestinal tract more often, and have more severe clinical manifestation and pathological process, as compared with Chinese patients.

Adolescent ; Adult ; China ; Crohn Disease ; ethnology ; pathology ; Female ; Humans ; Male ; Middle Aged ; United States ; Young Adult

Currently, pediatric emergency medicine (PEM) as practiced in many developed countries is different from ours in China. Chinese pediatric emergency medicine is just children's internal medicine and does not include general surgery, ear-nose-throat, etc. If children have an emergency condition that require specialized treatments they need to go to different departments. However in Canada, the pediatric emergency physicians will first treat the patients whatever the condition, then, if it is a complicated sub specialty problem, they will consult the specialist or let the patient see the specialist later. In addition, resuscitation is done in the pediatric intensive care unit (PICU) in China, but it is done in the emergency room in Canada. This article compares the differences in the pediatric emergency systems in Canada and China and also introduces the international standard system of pediatric triage.
Canada ; Child ; China ; Emergency Medicine ; education ; Humans ; Internship and Residency ; Pediatrics ; education ; Triage

Objective: To describe the situation of insufficient sleep and the association between insufficient sleep and physical exercise, among Chinese Han students aged 9-18 years. Methods: We selected 172 197 Chinese Han students aged 9-18 years from the project 2014 Chinese National Survey on Students Constitution and Health. The average sleep duration per day of less than 9 h for children aged 9-12 years and of less than 8 h for adolescents aged 13-18 years, were defined as insufficient sleep. We described the distribution of sleep duration and the prevalence rates of insufficient sleep for each subgroup. Logistic regression models were established to assess the association between insufficient sleep and physical exercise. Results: In 2014, 6.6%, 30.8%, 26.3%, 20.8%, 13.8% and 1.8% of the Chinese Han students self-reported sleep duration were <6, 6-, 7-, 8- and ≥10 h, respectively. The overall prevalence rate of insufficient sleep was 77.2%, with 75.8% for boys and 78.6% for girls. No gender disparity was found at each 9-11 age groups. However, in the 12-18 age groups, the prevalence rates for girls were significantly higher than that for boys. The prevalence rates of insufficient sleep for primary school, middle school and high school students were66.6%, 74.1% and 93.8%, respectively. Rates were increasing with age for children aged 9-12 years and adolescents aged 13-18 years respectively. The three provinces with the lowest prevalence rates of insufficient sleep were Zhejiang (68.8%), Jiangsu (66.7%) and Shaanxi (65.2%). Data from the logistic regression models revealed that, when comparing to those students with only exercise of <0.5 h per day, the exercise hours of 0.5-1 h (OR=0.72, 95%CI: 0.69-0.74) or ≥1 h (OR=0.46, 95%CI: 0.44-0.47) per day seemed as protective factors for insufficient sleep. When compared with physical exercise frequency <2 times per week, the 2 times (OR=0.82, 95%CI: 0.78-0.86) or >2 times (OR=0.65, 95%CI: 0.62-0.68) frequencies also appeared as protective. Conclusions: The prevalence rate of insufficient sleep prevailing among students aged 9-18 years was high, in China. Our data called for setting up effective measures to deal with this situation.
Adolescent ; Asian People/statistics & numerical data* ; Child ; China ; Exercise ; Female ; Humans ; Male ; Schools ; Sleep ; Sleep Deprivation ; Students ; Surveys and Questionnaires