Correlation of in vivo and in vitro methods in measuring choroidal vascularization volumes using a subretinal injection induced choroidal neovascularization model.

BACKGROUND: In vivo quantification of choroidal neovascularization (CNV) based on noninvasive optical coherence tomography (OCT) examination and in vitro choroidal flatmount immunohistochemistry stained of CNV currently were used to evaluate the process and severity of age-related macular degeneration (AMD) both in human and animal studies. This study aimed to investigate the correlation between these two methods in murine CNV models induced by subretinal injection. METHODS: CNV was developed in 20 C57BL6/j mice by subretinal injection of adeno-associated viral delivery of a short hairpin RNA targeting sFLT-1 (AAV.shRNA.sFLT-1), as reported previously. After 4 weeks, CNV was imaged by OCT and fluorescence angiography. The scaling factors for each dimension, x, y, and z (µm/pixel) were recorded, and the corneal curvature standard was adjusted from human (7.7) to mice (1.4). The volume of each OCT image stack was calculated and then normalized by multiplying the number of voxels by the scaling factors for each dimension in Seg3D software (University of Utah Scientific Computing and Imaging Institute, available at http://www.sci.utah.edu/cibc-software/seg3d.html). Eighteen mice were prepared for choroidal flatmounts and stained by CD31. The CNV volumes were calculated using scanning laser confocal microscopy after immunohistochemistry staining. Two mice were stained by Hematoxylin and Eosin for observing the CNV morphology. RESULTS: The CNV volume calculated using OCT was, on average, 2.6 times larger than the volume calculated using the laser confocal microscopy. The correlation statistical analysis showed OCT measuring of CNV correlated significantly with the in vitro method (R 2 =0.448, P = 0.001, n = 18). The correlation coefficient for CNV quantification using OCT and confocal microscopy was 0.693 (n = 18, P = 0.001). CONCLUSIONS: There is a fair linear correlation on CNV volumes between in vivo and in vitro methods in CNV models induced by subretinal injection. The result might provide a useful evaluation of CNV both for the studies using CNV models induced by subretinal injection and human AMD studies.

[Characteristic of medical support and health care for Shenzhou-5 and Shenzhou-6 astronauts at main landing site].

OBJECTIVE: To investigate the characteristics of medical support and health care for the Shenzhou-5 and Shenzhou-6 astronauts at the main landing site, with special emphasis on the technical requirements for two astronauts during flight, in order to provide reference data for medical support in the battle field and disasters. METHODS: The data associated with accidental injuries of astronauts during the space flight collected from foreign nations and domestically were reviewed retrospectively. Based on the experience in medical support for Shenzhou-5 and Shenzhou-6 astronauts and the special environments of field operations, a scheme for first-aid and emergent treatment were drafted for a system of organization, prophylactic measurements, equipment and their effective implementation pending the test in the real situation. RESULTS: Two sets of high-quality intensive care unit (ICU) equipment were set up in helicopters, and an ambulance was equipped with the instruments and facilities that could be used in the first-aid and surgical operation in case accident and injuries should happen. The three sets of highly mobile ICU mentioned above could cover a vast area of both grassland and desert at the landing site to ensure that the astronauts could be rescued should accident occur, reaction to emergency would be most rapid and technique and equipment would be best. This scheme of first-aid for emergency which might occur in astronauts would seem to be a scientific, reasonable and practical system and would also meet the need in battle field. CONCLUSION: The first-aid scheme for astronauts at the main landing site, and its equipment, first aid strategies as well as it execution might provide an advanced system for medical aid and emergency treatment in the battlefield, disasters, and other special occasions.

[Establishment of a mobile intensive care unit].

OBJECTIVE: To discuss the experience of establishment of a mobile intensive care unit (ICU) for emergency treatment following astronaut flight, disaster, and regional war. METHODS: The data from both foreign and our countries as well as our own clinical experience of first-aid were reviewed, and a mobile ICU was established, including the equipment, supply of drugs, training, and organization. RESULTS: The mobile ICU was set up at the site of landing of the first Chinese astronaut, and proved to be efficient. The new model could be expected to be prompt in first-aid for casualties in disasters and warfare. CONCLUSION: The first-aid on spot of casualties might reduce the rates of invalidity and mortality during disasters and regional war.

[Measure on medical care and rescue for the first Chinese astronaut during manned space flight].

OBJECTIVE: To discuss the experience of medical care and rescue for the first Chinese astronaut during manned space flight. METHODS: Review the experiences of foreign nations in respect to accidental injuries of astronaut during manned space flight, the possible reasons were analyzed, and accordingly a reasonable and effective prophylactic measures and health care were formulated. RESULTS: An effective mobile intensive care unit (ICU) was established on desert or prairie where the capsule would land, so as to ensure the safety of the first Chinese astronaut, and to provide intensive care as well as successful emergency treatment in case of accidental injuries. CONCLUSION: Reasonable and effective prophylactic measures and health care appear to be an important aspect of the successful manned space flight.