Objective:To investigate the effects on the new bone formation by different distraction rate during mandibular distraction osteogenesis in goats.Methods: The right side mandibles of twelve goats were distracted after corticortomy,and all the animals were divided into 3 groups randomly, the first group were distracted with 0.8 mm/day, the second group were distracted with 1.6 mm/day, the third group were distracted with 2.0 mm/day, and the left side mandible of 4 goats from above groups were selected randomly as the control group.Then the new generation bone after distraction with different rate were studied by bone density examination and three point bending test.Results: The bone density value of the 0.8 mm/day group were higher than the other two experimental groups; the results of three point bending test showed that the biomechanical strength of the new generation bone in 0.8 mm/day group was higher than the other two experimental groups.Conclusion:0.8 mm/day may be the best distraction rate in mandibular distraction osteogenesis.

This study investigated the effect of prolonged walking with load carriage on body posture, muscle fatigue, heart rate and blood pressure of the tested subjects. Ten healthy volunteers performed 30 min walking trials on treadmill (speed = 1.1 m/s) with different backpack loads [0% body weight (BW), 10% BW, 15% BW and 20% BW]. The change of body posture, muscle fatigue, heart rate and blood pressure before and after walking and the recovery of muscle fatigue during the rest time (0, 5, 10 and 15 min) were collected using the Bortec AMT-8 and the NDI Optotrak Certus. Results showed that the forward trunk and head angle, muscle fatigue, heart rate and blood pressure increased with the increasing backpack loads and bearing time. With the 20% BW load, the forward angle, muscle fatigue and systolic pressure were significantly higher than with lighter weights. No significantly increased heart rate and diastolic pressure were found. Decreased muscle fatigue was found after removing the backpack in each load trial. But the recovery of the person with 20% BW load was slower than that of 0% BW, 10% BW and 15% BW. These findings indicated that the upper limit of backpack loads for college-aged students should be between 15% BW and 20% BW according to muscle fatigue and forward angle. It is suggested that backpack loads should be restricted to no more than 15% BW for walks of up to 30 min duration to avoid irreversible muscle fatigue.
Blood Pressure ; Body Weight ; Exercise Test ; Healthy Volunteers ; Heart Rate ; Humans ; Muscle Fatigue ; Posture ; Walking ; physiology ; Weight-Bearing

Objective To investigate the impairment and the effect factors of encoding of episodic memory in patients with cerebral infarction. Methods 112 cases cerebral infarction patients and 115 healthy elders as controls were tested for episodic memory encoding with episodic pictures accomplished in computer, and compare the differences of encoding of episodic memory between the two groups. Results The remember indexes ( REM )of encoding memory test in patient group was significantly lower than that in control group( (70.81 ± 6.08 )vs (84.67 ± 4.49), P ＜ 0.01 ). The REM in patients with different impaired areas was significantly different ( (65.88 ± 5.73 ), (68.92 ± 4.65 ), (73.39 ± 6.20), ( 73.53 ± 3.44), P ＜ 0. 01 ). The REM in frontal lobe infarction group was significantly lower than that in temporal lobe infarction group (P ＜ 0.05 ), and in temporal lobe infarction group was significantly lower than that in basal ganglia infarction group and corona radiate infarction group (P＜0.05, P＜0. 01). The REM in cortex infarction group was significantly lower than that in under cortex group ( ( 67.37 ± 5.40 ), ( 73.46 ± 4.99 ), P ＜ 0.01 ). The REM in small cerebral infarction group was significantly higher than that in large cerebral infarction group( (72.67 ±4.47 ), (67.56 ± 6.18 ), P＜0.01 ). The size of cerebral infarction diameter was related with the REM( r= -0.39, P＜0. 01 ). The REM among control group,infarction with atrophy group, and infarction without atrophy group were significantly different( (67.03 ± 6. 17 ),( 72.84 ± 5. 00 ), ( 84.67 ± 4.49 ), P ＜ 0. 01 ). The REM in infarction with atrophy group was significantly lower than that in infarction without atrophy group and control group( both P＜0.01 ) ,The REM in infarction without atrophy group was significantly lower than that in control group (P ＜ 0.01). Conclusion The encoding of episodic memory was impaired in cerebral infarction patients. The infarction parts,size of infarction area and atrophy was related with the impairment of encoding of episodic memory.

Objective To investigate the relationship between the residual forward blood flow and the therapeutic outcome in patients with acute cerebral infarction after arterial thrombolysis treatment. Methods During the period from January 2009 to December 2013 at authors’ hospital, a total of 40 patients with acute anterior circle cerebral infarction were treated with arterial thrombolysis. The clinical data were retrospectively analyzed. The patients were divided into group A (n=23) when residual forward blood flow and/or collateral circulation were presented, and group B (n=17) if no residual forward blood flow and/or collateral circulation were detected. The NIHSS scores and hemorrhagic transformation state were determined 14 days after the thrombolysis treatment, and the results were compared between the two groups. Results In group A, 21 cases (91.3%) showed complete or partial re- canalization of the infracted vessels, and asymptomatic hemorrhagic transformation was seen in one case. The pre-treatment NIHSS score was 12.69 ± 3.88 and the post-treatment NIHSS score was 6.05 ± 3.25. In group B, complete or partial re-canalization of the infracted vessels was seen in 15 cases (88.2%), asymptomatic hemorrhagic transformation was found in one case and symptomatic hemorrhagic transformation occurred in one case, who died of massive cerebral hemorrhage seven hours after the thrombolysis treatment. The pre-treatment NIHSS score was 13.51 ± 4.19 and the post-treatment NIHSS score was 8.68 ± 5.16. The differences between the two groups were statistically significant (P < 0.05). The obvious effect rate in group A and group B was 68.1% and 43.8% respectively, and the effective rate in group A and group B was 86.3% and 56.3% respectively, indicating that the clinical outcome of group A was much better than that of group B. Conclusion The therapeutic effect of arterial thrombolysis for acute cerebral infarction patients is not only closely related to the time window but also to the residual forward blood flow. The more the residual forward blood flow there is, the better the therapeutic result with less risk of hemorrhagic transformation will be.

We assessed the effects of pulsatile flow shear stress on the gene expression profiles of human umbilical artery smooth muscle cells (HUASMCs) in vitro using the Express Chip DNA microarray method and investigated the difference between pulsatile and steady shear stress on differentially expressed genes of HUASMCs. In a modified pulsatile flow chamber system, HUASMCs were exposed to pulsatile and steady fluid shear stress (5.52 dyne/cm2) for 6 h respectively, and normal static cultured HUASMCs were selected as a control. The total cellular RNA was extracted by TRIzol Reagent (Life Technologies, Inc) according to the manufacturer's manual. Conversion of mRNA to single strand cDNA and double strand cDNA template was synthesized by Reverse Transcription from the total RNA. cRNA probe was transcribed with biotin labeling. After hybridization of probe with microarray, the binding of streptavidin to biotin was performed and amplified with the first antibody and further amplified with Cy3-conjugated second antibody. Then detection of Cy3 dye was carried out with ScanArray 5000. The results showed that a total of 1,330 genes revealed differential expression in HUASMCs exposed on pulsatile shear stress (5.52 dyne/cm2, 6 h); however, 2,676 genes revealed differential expression in HUASMCs exposed on steady shear stress. Comparsion of HUASMCs exposed to pulsatile with the HUASMCs exposed to steady shear stress showed there were 2,297 genes revealing differential expression. The transcriptional profile of fluidally induced genes in HUASMCs suggested a different response to pulsatile and steady shear stress.
Cells, Cultured ; Gene Expression Profiling ; Humans ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Oligonucleotide Array Sequence Analysis ; Pulsatile Flow ; RNA, Messenger ; biosynthesis ; genetics ; Stress, Mechanical ; Umbilical Arteries ; cytology

The purpose of this study was to investigate the effect on the expression of NF-kappaBp65 of osteoblast-like cell under stretch load with the same amplitude but different daily loading times. The osteoblast-like cells MG-63 were passage cultured and stretched by the four-point-bend loading device; based on the daily loading times, the osteoblast-like cells were randomly divided into four groups. The first was the control, the others were stretched with mechanical tension with the same amplitude of 2,000 mu strain and at the same frequency of 0.5 Hz., but the daily loading times were 1 time/d, 2 times/d, 4 times/d differently for each group, the periods of mechanical tension applied to the cells of the three groups were all 60 min/d and lasted for 2d total. After the cells being streteched, the expression levels of NF-kappaBp65 of the osteoblast-like cells of the three groups and control group were investigated by using the techniques of immunohistochemistry, and were compared with each other. The results showed that the positive expression ratios of the four groups were different significantly; the positive expression ratio of the control was lower than those of the other three groups; the positive expression ratio of the 4 times/d group was higher than those of the other two stretched groups; the positive expression ratio of the 2 times/d group was higher than that of the 1 time/d group. The results suggested that when the osteoblast-like cell was under the stretch load with different daily loading times but the same amplitude, the expression ratio of NF-kappaBp65 in the cell increased with the rising of the stimulating times. It means that the mechanical strain with high daily loading times could promote the transcriptional level of osteoblast-like cell more effectively.
Cell Line ; Humans ; Mechanotransduction, Cellular ; Osteoblasts ; cytology ; metabolism ; Stress, Mechanical ; Time Factors ; Transcription Factor RelA ; biosynthesis

The number of combination products is increasing, and the cutting-edge and innovative technologies are constantly being used. How to evaluate combination products become difficult points. This study team summarizes the supervision conditions of the combination products and analyzes the common problems of these products application from the perspective of technical review, in order to provide reference for Chinese manufacturers and investigators in these products registration.
Biomedical Technology

This article summarizes the attribute conditions to the combination products designation from 2009 to 2018 in China,analyzes the common problems of combination products attribution definition.It is hoped to be helpful for researchers and manufacturers of combination products.
China ; Equipment and Supplies ; Terminology as Topic

Objective To make classification and segment measurement for the cases with tibiofibular and ankle fractures in parachuting landing, and investigate main classification types of parachuting fractures and fracture segments of high risk.Methods A total of 56 fracture cases in parachuting landing were collected, and the tibiofibula and ankle fractures were classified according to AO-OTA or Lauge-Hansen classification standards respectively based on their digital X-ray images. The medium plane between talus and tibia joint planes in ankle joint was defined as the reference plane. The highest and lowest injury points of tibia and fibula were marked respectively, and the fracture segment was defined between the highest and lowest point for statistical analysis.Results For tibiofibular and ankle fracture cases in parachuting landing, fracture at both tibia and fibula accounted for 80.4%. The major classification of tibiofibula fracture was 42-D/5.2 (45.8%) and 42-D/5.1 (16.7%). The major classification for ankle fracture was pronation-external rotation (PER, 59.4%) and supination-external rotation (SER, 37.5%). When tibiofibular and ankle fracture cases in parachuting landing occurred, the fracture segment of the tibia was mainly from 57 to 143 mm above the reference plane and from 6 mm below the reference plane to 24 mm above the reference plane, while the fracture segment of the fibula was 4-45 mm and 74-83 mm above the reference plane. Injury risks of all above segments were higher than 50%.Conclusions For protection of lower limbs in parachuting landing, the fracture at both tibia and fibula should be highly noticed. The ankle motion of PER and SER should be especially restricted in parachuting ankle protection.

Metformin has been used for the treatment of type II diabetes mellitus for decades due to its safety, low cost, and outstanding hypoglycemic effect clinically. The mechanisms underlying these benefits are complex and still not fully understood. Inhibition of mitochondrial respiratory-chain complex I is the most described downstream mechanism of metformin, leading to reduced ATP production and activation of AMP-activated protein kinase (AMPK). Meanwhile, many novel targets of metformin have been gradually discovered. In recent years, multiple pre-clinical and clinical studies are committed to extend the indications of metformin in addition to diabetes. Herein, we summarized the benefits of metformin in four types of diseases, including metabolic associated diseases, cancer, aging and age-related diseases, neurological disorders. We comprehensively discussed the pharmacokinetic properties and the mechanisms of action, treatment strategies, the clinical application, the potential risk of metformin in various diseases. This review provides a brief summary of the benefits and concerns of metformin, aiming to interest scientists to consider and explore the common and specific mechanisms and guiding for the further research. Although there have been countless studies of metformin, longitudinal research in each field is still much warranted.
Humans ; Metformin/pharmacokinetics* ; Diabetes Mellitus, Type 2/metabolism* ; Hypoglycemic Agents/pharmacology* ; AMP-Activated Protein Kinases/metabolism* ; Aging