| Millimeter wave is belong to the 30~300 GHz of electromagnetic wave and its wavelength is 1~10mm. At present,studies of millimeter wave mainly focussed on 35 GHz,60 GHz and 94 GHz frequency, which are mostly used in physical therapy and research of military domain. The penetration of millimeter wave was very feeble, and its penetration was only 0.23~0.78 mm in distilled water. Millimeter wave could only penetrate the shallow layer of tissue and arrive on only the papillary layer and reticular layer of corium and could only make damnification of cornea and skin, when irradiated animals in little times. In addition, millimeter wave is very easy to be affected by different medium in spread, but high power millimeter wave could make skin give birth to a biting sense, and this sense disappeared when turn off the emitter of millimeter wave and left the range of millimeter wave irradiation. Therefore, millimeter wave could achieve quick avoidance and could dispel quickly huddle crowd without the casualty and prevent rebellion. As a result, we would investigate mostly millimeter wave irradiation and had finished the experiment of lethal mice by millimeter wave and continuous and acute heat exposure. The aim acquired the different lethal liminal parameters for high power millimeter wave irradiation(the lethal parameters of power densities, irradiated distances and irradiated times), the time of lethal mice due to continuous and acute heat exposure as well as the variational regulation between survival time and irradiated temperature and the change of relative pathology and modality. In addition, we expatiated approximately on the investigation of high power millimeter wave and heat exposure to lethal mice. In significant, our experiments supplied important information for thorough research of millimeter wave.To investigate the liminal parameters of lethal mice and change of pathology and modality by 34.1 GHz high power millimeter wave irradiation, the Balb/c mice were vertically placed under the high power millimeter wave equipment with working frequence 34.1 GHz, and mean output power to be 5 W, 10 W and 12 W while the distance between the animal and the bottom of the irradiation horn to be 10 mm and 20 mm respectively. The mouse was tied on the platform and continuously received the irradiation until death. After immediate dissection, the mouse lung, skin and brain were quickly rinsed with 0.9% NaCl solution, fixed in 10% formaldehyde solution and embedded and prepared the tissue slice with paraffin. Then the HE staining and taking photos with a CCD camera, the Image Pro Plus software and quantitative image analyzing method by combining the mean optical density and area was used to determine the pathological characters of the lung. After received irradiation by using the HD-320-HA23.16 and HD-320-HA9.92 pyramid horns with different physical parameter,it seemed that the continuous irradiation with mean power of 12 W is the most critical parameter leading to animal death, while the death time is only about 110 sec. Meanwhile, death time for the animal is about 30 min after receiving the lower mean power (5 W) continuous irradiation. There is significant hemorrhage in the mouse lung with high power millimeter irradiation, although the hemorrhage degree is different under different irradiation parameters. When the mean power are 10 W and 12 W,the hemorrhage degree of lung is extremely significant, where the bronchia and blood vessel of lung was markedly broken. A lot of cells of bronchia had been released after high power millimeter wave irradiation. However, when the mean power is 5 W, the hemorrhage degree of lung is less destroyed, while the bronchia and blood vessel of lung has not severe fracture phenomenon. High power millimeter wave irradiation has remarkable effect on mouse lung. The degree of damnification to lung tissue was positive relationship with millimeter irradiation, which was greater when the mean power was higher. As the high power millimeter used in this study is able to result in significant thermal effect to the animals, it is suggested that the acute heat-induced insults likely led to animal death by cauing serious lung injury.To investigate thoroughly the bio-effect of millimeter wave, we utilized the oven to simulate heat effect of millimeter wave irradiation. Above all, we preestablished different radiant temperatures to irradiate Balb/c mice, until their death. First of all,animals were placed in an oven with different temperatures preestablished (43~61°C with an interval incremental of 2°C) to receive acute and continuous heat exposure until death. Immediately after dissection, after the skin of mice and brain were quickly rinsed with 0.9% NaCl solution, fixed in 10% formaldehyde solution and embedded and prepared the tissue slice with paraffin. After the HE staining and taking photos with a CCD camera, we analyzed the damnification of skin tissue and pallium's neuron by Image Pro Plus software. However and surprisingly, our data strongly showed that mean survival time of the mice was significantly related to the preestablished temperatures in an exponential decay curve with a very high correlative coefficient (R=0.9994). Additionally, the body weight of mice had very marked difference before and after heat exposure when preestablished temperatures were difference, and compared with sham, all showed most marked difference. At last, heat exposure colud also make skin'construction change and be damaged and could also break the neuron of cerebral cortex. As a result, we could know clearly supreme liminal parameters of lethal mice and change pathology and modality as well as change of the body weight by continuous and acute heat exposure.In addition,to investigate the effect of heat exposure to mice, a majority of skins of mice for wiping off hair were quickly rinsed by 0.1% DEPC water and saved in liquid nitrogen before use. Then distilled mRNA and reverse transcription,PCR was used to examine the heat-shock related genes expression in skin of mice followed with image analysis. Results showed that expression of hsp70, krt6αand thbs1 were significantly upregulated in the temperatures examined. During which, the upregulation of hsp70 with the temperatures for exposure shown a gradually descend pattern but not for krt6αand thbs1. In addition, the upregulation of hsp105 could be observed in relatively lower temperatures but not in higher temperatures. In conclusion, our data suggested that acute and continuous heat exposure significantly influence the expression of heat-shock related genes in mice skin, while the expression pattern of different genes were largely related with the temperatures during heat exposure. Additionally, hsp70 might be considered as a biomarker to quantify the degrees of heat exposure injury in the body.In conclusion, this study utilized millimeter wave irradiation and heat exposure of oven to investigate the lethal effect of mice. We acquired the liminal parameters of lethal mice and the character of damnification to lung by investigating different parameters'millimeter wave to lethal mice (horn antennas, output powers and irradiated distances); besides, we acquired the lethal times of mice and pathological character of different tissues in different irradiated temperatures by simulating millimeter wave experiment. In significant, we acquired also the regulation and relation between irradiated temperature and survival time. All these researches established well foundation for the bio-effect of millimeter wave irradiation. |
PDF Full Text Request