8-hydroxy-2-(di-n-propylamino)tetralin intervenes with neural cell apoptosis following diffuse axonal injury

Previous studies have reported a neuroprotective effect of 8-hydroxy-2-（di-n-propylamino）tetralin （8-OH-DPAT） against traumatic brain injury. In accordance with the Marmarou method, rat models of diffuse axonal injury were established. 8-OH-DPAT was intraperitoneally injected into model rats. 8-OH-DPAT treated rats maintained at constant temperature served as normal temperature controls TUNEL results revealed that neural cell swelling, brain tissue necrosis and cell apoptosis occurred around the injured tissue. Moreover, the number of Bax-, Bcl-2- and caspase-3-positive cells increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. However, brain injury was attenuated, the number of apoptotic cells reduced, Bax and caspase-3 expression decreased, and Bcl-2 expression increased at 6, 12, 24, 72 and 168 hours after diffuse axonal injury in normal temperature control and in 8-OH-DPAT-intervention rats. The difference was most significant at 24 hours. All indices in 8-OH-DPAT-intervention rats were better than those in the constant temperature group. These results suggest that 8-OH-DPAT inhibits Bax and caspase-3 expression, increases Bcl-2 expression, and reduces neural cell apoptosis, resulting in neuroprotection against diffuse axonal injury. This effect is associated with a decrease in brain temperature.

Applying Anomaly-based Weather Analysis to the Prediction of Low Visibility Associated with the Coastal Fog at Ningbo-Zhoushan Port in East China

Low visibility episodes (visibility < 1000 m) were studied by applying the anomaly-based weather analysis method. A regional episode of low visibility associated with a coastal fog that occurred from 27 to 28 January 2016 over Ningbo- Zhoushan Port, Zhejiang Province, East China, was first examined. Some basic features from the anomalous weather analysis for this case were identified:(1) the process of low visibility mainly caused by coastal fog was a direct response to anomalous temperature inversion in the lower troposphere, with a warm center around the 925 hPa level, which was formed by a positive geopotential height (GPH) anomaly in the upper troposphere and a negative GPH anomaly near the surface;(2) the positive humidity anomaly was conducive to the formation of coastal fog and rain;(3) regional coastal fog formed at the moment when the southwesterly wind anomalies transferred to northeasterly wind anomalies. Other cases confirmed that the low visibility associated with coastal fog depends upon low-level inversion, a positive humidity anomaly, and a change of wind anomalies from southwesterly to northeasterly, rain and stratus cloud amount. The correlation coefficients of six-hourly inversion, 850?925-hPa-averaged temperature, GPH and humidity anomalies against visibility are ?0.31, 0.40 and ?0.48, respectively, reaching the 99% confidence level in the first half-years of 2015 and 2016. By applying the anomaly-based weather analysis method to medium-range model output products, such as ensemble prediction systems, the anomalous temperature?pressure pattern and humidity?wind pattern can be used to predict the process of low visibility associated with coastal fog at several days in advance.

Expression of angiogenic factors in cerebral arteriovenous malformations

BACKGROUND： In the process of vascularization, vascular endothelial growth factor （VEGF）, angiopoietin-2 and Tie2 are involved in the migration, differentiation and proliferation of vascular endothelial cells, and stimulate the rapid angiogenesis; Tiel and angiopoietin-1 play important roles in facilitating the formation of vascular lumen and maintaining the integrity of vascular wall. Thus the distributions and expressions may be associated with the occurrence of cerebral arteriovenous malformation. OBJECTIVE： To observe the biological effects of angiogenic factors in the occurrence and development of cerebral arteriovenous malformation. DESIGN： An observational comparative experiment. SETTINGS： Department of Neurosurgery, General Hospital of Shenyang Military Area Command of Chinese PLA; Department of Neurosurgery, General Hospital of Tianjin Medical University. PARTICIPANTS： Fresh samples of complete cerebral arteriovenous malformations resected in 47 patients were collected from the Department of Neurosurgery, General Hospital of Tianjin Medical University from August 1999 to May 2001, including 22 males and 25 females, the mean age was 34.5 years. Informed consents were obtained from all the patients or their relatives. The initial symptom was hemorrhage in 28 cases. All the patients were classified according to the clinical imaging data and Spetzler-Martin grading standard, including 11 cases of grade Ⅰ, 17 cases of grade Ⅱ, 11 cases of grade Ⅲ, and 8 cases of grade Ⅳ - Ⅴ. Normal brain tissues resected by decompression due to trauma were taken from 8 patients as controls, including 5 males and 3 females, aging 12 - 65 years. METHODS： ① The expressions of VEGF, Tie receptors, angiopoietin-1, angiopoietin-2, proto-oncogene c-myc and proliferating cell nuclear antigen（PCNA） in the samples of cerebral arteriovenous malformation were detected with immunohistochemical method. Under light microscope, the positively stained rat-anti-human factor Ⅷ-related antigens （specific marker of vascular endothelial cells） were counted, then the immuno-positive cells of the other antibodies in the visual field of neighboring section which was in ＂mirror＂ relation were counted, and the percentage of the latter to the former was considered as the labeling index of positive cells. The immunostaining intensity was classified negative （ - ）： no positive cells; positive （＋）： number of positive cells 〈 20%; moderately positive （＋＋）： number of positive cells 20% - 50%; strongly positive （＋＋＋）： number of positive cells 〉 50%. ② The differences of the enumeration data were compared with chi-squam test, and the correlation were analyzed with the linear correlation analysis. MAIN OUTCOME MEASURES： Expressions and distributions of VEGF, Tie 1 and Tie2 receptors, angiopoietin-1, angiopoietin-2, PCNA and c-myc in the samples of cerebral arteriovenons malformation and normal brain tissue. RESULTS： ① Expressions of angiogenic factors in the control group and cerebral arteriovenons malformation groups of each grade： The positive rates of VEGF, Tie2, angiopoietin-2, c-myc and PCNA expressions in the control group were significantly different from those in the cerebral arteriovenous malformation groups of each grade （ x^2=21.09 - 34.23, P 〈 0.05）, whereas the positive rates of Tiel and angiopoietin-1 expressions were close （ x^2=3.43 - 3.869, P 〉 0.05）. ② Expressions of angiogenic factors in hemorrhage group and non-hemorrhage group： The expressions of VEGF, angiopoietin-2 and PCNA in the hemorrhage group were significantly lower than those in the non-hemorrhage group （ x^2= 16.22 - 26.56, P 〈 0.05）. There ware no obvious differences in the expressions of Tiel and angiopoietin-1 expressions between the hemorrhage group and non-hemorrhage group （ x^2=3.22 - 3.78, P 〉 0.05）.The VEGF was positively correlated with the expressions of c-myc and PCNA （r = 0.728, 0.916, P 〈 0.05）. CONCLUSION： ①The expressions of angiogenic factors and related receptors may be involved in the process of cerebral arteriovenous malformation, and had important correlation the its clinical grading. ② Angiogenic factors may induce the expression of endothelial cell c-myc in cerebral arteriovenous malformation, and then interfere the cell proliferation and apoptosis.