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A gelatin hydrolysate with a hydrolysis degree of 13.7% was generated using the skin gelatin of chum salmon (Oncorhynchus keta) and papain-catalyzed enzymatic hydrolysis. The results of analysis demonstrated that four amino acids, namely Ala, Gly, Pro, and 4-Hyp, were the most abundant in the obtained gelatin hydrolysate with measured molar percentages ranging from 7.2% to 35.4%; more importantly, the four amino acids accounted for 2/3 of the total measured amino acids. However, two amino acids, Cys and Tyr, were not detected in the generated gelatin hydrolysate. The experimental results indicated that the gelatin hydrolysate at a dose of 50 µg/mL could combat etoposide-induced apoptosis in human fetal osteoblasts (hFOB 1.19 cells), causing a decrease in the total apoptotic cells from 31.6% to 13.6% (via apoptotic prevention) or 13.3% to 11.8% (via apoptotic reversal). Meanwhile, the osteoblasts exposed to the gelatin hydrolysate showed expression changes for 157 genes (expression folds > 1.5-fold), among which JNKK, JNK1, and JNK3 were from the JNK family with a 1.5–2.7-fold downregulated expression. Furthermore, the protein expressions of JNKK, JNK1, JNK3, and Bax in the treated osteoblasts showed a 1.25–1.41 fold down-regulation, whereas JNK2 expression was not detected in the osteoblasts. It is thus suggested that gelatin hydrolysate is rich in the four amino acids and has an in vitro antiapoptotic effect on etoposide-stimulated osteoblasts via mitochondrial-mediated JNKK/JNK(1,3)/Bax downregulation.

A composite structure health monitoring system with optical fiber sensors is an important development in smart materials and structures. But it is difficult to embed a network of distributed optical fiber sensors in a smart composite structure, and the most effective method would be integrating the network of sensors with the polyimide film as a layer, called the optical fiber sensor layer, and then embedding the layer with optical fiber sensors in the composite material. This paper introduces three methods of making a distributed optical fiber sensor layer with polyimide. The first is to sandwich optical fiber sensors in two polyimide films. The second is to deposit the network of sensors in polyimide solution, and dry the polyimide solution. The last is to build thin-film optical waveguides and optical sensors by using fluorinated polyimide, which is expected to have high integration and high reliability. Some tests indicate that there is a little influence on the mechanical performance of the structure; however, optical fiber sensor built-in polyimide films work very well.

The aim of the present study was to examine the effects of simulated heliox diving at high altitudes on divers' blood cells, liver functions and renal functions. In this experiment, four divers lived for nine consecutive days in a dual-function high-low pressure chamber, which simulated air pressure at an altitude of 3,000 meters and at a 30-meter depth; an altitude of 4,000 meters and 30-meter depth; and at an altitude of 5,200 meters and 30 meters and 50 meters in depth. Total time underwater was 60 minutes. The subjects breathed heliox (with oxygen at 40% and helium at 60%) during the simulated 30-meter dive from zero altitude to 30 meters and while remaining underwater; they breathed air while ascending from 30 meters to 18. They breathed heliox (with oxygen at 26.7% and helium at 73.3%) in the simulated dive from zero altitude to 50 meters underwater, in remaining underwater and in ascending from 50 meters to 29; air while ascending from 29 meters to 18. Pure oxygen was breathed while ascending from 18 meters to the surface; then air. Results indicated: (1) the correlating indices of routine blood, liver and renal functions, and urine routine were all within normal reference ranges; and (2) the indices tested at other periods of time were not significantly different (p0.05) from the results at zero-meter level and 3,000-meter level. The study suggests that the heliox diving processes at different high altitudes simulated in this experiment have no significant impact upon divers' blood routine, liver functions and renal functions.

To observe the change in contents of creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) in peripheral blood, the elevation of ST in electrocardiogram, and the result of coronary arteriography, to identify myocardial damage and acute myocardial infarction during cardiopulmonary resuscitation (CPR).Twenty-six patients with sudden cardiac arrest received CPR, and those patients who had blood circulation maintained for over 24 hours were included. The expression of CK-MB and cTnI activation in peripheral blood were determined at 0, 4, 8, 12, 16 and 20 hours after CPR in all patients. Electrocardiogram was checked every 2 hours in all patients. If CK-MB, cTnI and ST segment of electrocardiogram was higher than usual, or myocardial infarct with suspicious elevation of ST (STEMI), coronary arteriography and interventional therapy were carried out immediately. Patients were divided into three groups. The patients who were not found to have coronary artery block were classified as group A (15 cases), those who were found to have coronary artery block were group B (6 cases), and the remaining patients in whom ST segment of electrocardiogram did not elevate, and coronary arteriography and interventional therapy were not consider were classified as group C (5 cases). Control group consisted of 15 healthy people (group D). The change in CK-MB and cTnI in peripheral blood and the elevation of electrocardiogram ST segment were analyzed.In group A, CK-MB level began to elevate at CPR 4 hours, and it peaked at CPR 12 hours. cTnI began to raise at CPR 4 hours, peaking at CPR 16 hours, then decreased gradually. Elevation of ST was seen in more than two leads in electrocardiogram at the beginning of restoration of spontaneous circulation (ROSC), then lowered quickly, and the decrease exceeded 50% of the elevation at ROSC 2 hours. In group B, the levels of CK-MB and cTnI began to increase at CPR 4 hours, and remained elevated at CPR 20 hours. ST segment was elevated in more than two leads in electrocardiogram at the beginning of ROSC, and remained elevated after ROSC 2 hours. In group C, the CK-MB and cTnI concentrations were increased 4 hours after successful CPR, and reached peak at CPR 12, 16 hours respectively, then they decreased. ST segment of electrocardiogram was not elevated. In group D, the CK-MB and cTnI concentration was in the normal range. ST segment of electrocardiogram was not elevated.All patients manifested myocardial damage after CPR. Some patients showed STEMI after CPR. CK-MB and cTnI concentrations increased gradually after successful CPR without specificity for earlier identification of myocardial damage and STEMI. It is necessary to find a new reliable marker to check for myocardial damage. Relatively speaking, elevation of the ST segment in electrocardiogram has more predictive value. A decrease exceeds 50% of the elevation of ST segment in electrocardiogram at ROSC 2 hours, or the peak of contents of CK-MB and cTnI appear at CPR 12 hours or 16 hours indicates myocardial damage. If the elevation of ST segment does not descend after ROSC 2 hours, or the levels of CK-MB and cTnI remain elevated at CPR 20 hours, STEMI should be suspected, and it is necessary to undertake interventional therapy or thrombolysis therapy.

To study the relationship between the protection of Ginsenoside(GS) for spinal cells and nitric oxide (NO).Spinal cells were cultured in vitro, the model of peripheral nerve was established by scarifying the cells, and NO was measured by Griess method.NO in injury group was high than that in noninjury group and NO in group cultured by GS was less than that in group cultured by common medium.NO increases when peripheral nerve is injuried, and the protective effect of GS on spinal cells may be through inhibiting NO release.