结直肠癌大鼠热创伤应激模型建立与评价

目的建立操作简便、重复性好的结直肠癌大鼠热创伤应激模型,用于研究围术期手术应激对肿瘤生长及肿瘤微环境的影响。方法健康雄性SD大鼠72只,采用随机数字表法分为正常对照组、癌症模型组和热创伤应激组3组,每组24只。癌症模型组和热创伤应激组用N-甲基-N-亚硝基脲(MNU)化学诱导法灌肠16周,建立MNU诱导的结直肠癌模型。16周后热创伤应激组大鼠分别以特制的阻热黄铜模板加热后进行热创伤刺激,并分别于热创伤刺激后0、6、12和24h各随机取6只大鼠取血和采集结直肠组织;正常对照组和癌症模型组也根据热创伤应激组处理时间各随机取6只大鼠取血和采集结直肠组织。采用ELISA法检测大鼠血清促肾上腺皮质激素(ACTH)、IL-6、IL-10、皮质酮水平,采用Western blot法检测结直肠组织细胞周期蛋白(Cyclin)D1和髓样细胞白血病-1(Mcl-1)蛋白水平。结果热创伤应激组大鼠血清ACTH、IL-6、IL-10、皮质酮水平较正常对照组和癌症模型组均升高,且热创伤应激组创伤应激后6、12、24h血清ACTH、IL-6、IL-10、皮质酮水平较应激后0h均升高,差异均有统计学意义(均P<0.05)。热创伤应激组4个时间点Cyclin D1和Mcl-1蛋白表达水平较正常对照组0h和癌症模型组0h均升高,且热创伤应激组创伤应激后6、12、24h Cyclin D1和Mcl-1蛋白表达水平较应激后0h均升高,差异均有统计学意义(均P<0.05)。结论结直肠癌大鼠热创伤应激模型具有操作简便、重复性好等优点;热创伤应激可激活IL-6诱导结直肠癌大鼠肿瘤增殖,该模型可用于围术期手术创伤对肿瘤微环境影响的机制研究。

Different Responses of Camptothecin and 10-Hydroxycamptothecin to Heat Shock in Camptotheca acuminata Seedlings

Plants interact with their environment by producing a diverse array of secondary metabolites, one of which is alkaloid. In this study, alkaloids, including camptothecin (CPT) and 10-hydroxycamptothecin (HCPT), malondialdehyde (MDA) and chlorophyll contents were measured during heat shock in seedlings of Camptotheca acuminata Decaisne unique to China. Responses of different tissues, including young leaves, old leaves, buds and barks, to heat shock were examined in alkaloid changes. CPT and HCPT concentrations reached their peak values separately at 38 degreesC and 40 degreesC, which were below the lethal heat-shock temperature indicated by MDA and chlorophyll, and their great changes took place in young leaves. These results indicated that CPT and HCPT were involved in the C acuminata resistance against heat shock from its environment. Furthermore, plant rigidly observed the cost-benefit principle and mobilized and allocated limited alkaloid sources to young and reproductive tissues preferentially. In addition, HCPT displayed well-regulated changes during incubation at sublethal temperature, and this indicated that HCPT might play a more positively defensive role in enhancement of plant thermotolerance than CPT does.

Effects of Traditional Chinese Medicine on Numbers of Lymphocytes and Goblet Cells in Villus Epithelia of Layers under Heat Stress

[Objective] This study aimed to investigate the effects of traditional Chinese medicine additives on numbers of lymphocytes and goblet cells in villus epithelia of layers under heat stress.[Method] A total of 180 88-d-old healthy Esa Brown cocks were selected.They were randomly divided into 9 experimental groups：Room temperature control,High temperature control,VC addition group,High formula I,Moderate formula I,Low formula I,High formula II,Moderate formula II and Low formula II.The formula I and formula II were to add different herbal extracts to the diet of cocks with different doses.The cocks in the VC addition group were administered orally with same-concentration VC solution.After certain time,the cocks were slaughtered.Then the numbers of epithelial lymphocytes and goblet cells in various segments of small intestine were counted by using conventional histological section and HE staining.[Result] The numbers of lymphocytes and goblet cells in villus epithelia of layers under heat stress were decreased gradually with the proceeding of experiment.The herbal extracts of formula I and formula II all could promote the generation of lymphocytes and goblet cells.But the promoting effect of formula II was best.[Conclusion] The Chinese herbal medicine additives have a good relieving effect on heat stress in layers.

Effects of Traditional Chinese Herbal Medicine on the Structure of Duodenal Mucosa of Chickens under Heat Stress

[Objective] This study aimed to investigate the effects of traditional Chinese herbal medicine on the structure of duodenal mucosa of chickens under heat stress. [Method] One hundred and twenty 88-day-old Isa Brown chickens were randomly divided into six groups, including three control groups （normal temperature control group, high temperature control group, high temperature Vc control group） and three high-temperature administration groups （high-dose administration group, moderate-dose administration group, low-dose administration group）. Chickens in normal temperature control group were reared at 14-25 ℃, and those in other five groups were reared at 28-39 ℃. The experiment lasted 10 d. Five chickens in each group were euthanized at 1, 4, 8 and 10 d post-treatment, respectively. The duodenal mucosa was collected and prepared into tissue slices with the conventional method for hematoxylin-eosin （HE） staining. Mucosal thickness, villus length and crypt depth of duodenal mucosa were measured. [Result] Under heat stress, duodenal mucosal thickness and villus length were both significantly lower than those in normal temperature control group, and the duodenal villi were scarce and thin. However, under high temperature conditions, various indicators in high-dose and moderate-dose administration groups were higher than those in high temperature control group and high temperature Vc control group, which exhibited extremely significant differences at 8 and 10 d post-treatment, especially. Moreover, various indicators in high-dose administration group were significantly higher than those in moderate-dose and low-dose administration groups. The traditional Chinese herbal medicine prescription exhibited higher protective effects on duodenal mucosa of chickens under heat stress compared with high temperature Vc control group. [Conclusion] Under heat stress, traditional Chinese herbal medicine reduced effectively the duodenal mucosa damage in chickens.

Effects of Traditional Chinese Herbal Medicines on Blood Ions and Enzymes of Egg-laying Hens Under Heat Stress

[Objective] This study was conducted to investigate the effects of tradi- tional Chinese herbal medicines on blood biochemical indices of egg-laying hens under heat stress and to provide theoretical basis for clinical application of the medicines. [Method] One hundred of 88-day-old ISA-Brown hens were randomly di- vided into five groups. The hens in four groups were administrated with Prescription I herbal medicines, Prescription II herbal medicines, Vc and blank control under ar- tificially simulated heat stress, respectively. The last group was raised under normal temperature condition. Blood samples of the hens were collected on 1, 4, 8 and 10 d later and detected for their biochemical indices. [Result] The blood sodium （Na）, phosphorus （P）, potassium （K） and chlorine （CI） concentrations in hens under heat stress were decreased, while the activities of alanine aminotransferase （ALT）, lactate dehydrogenase （LDH） and creatine kinase （CK） were increased. These indices grad- ually returned to normal levels after the use of traditional Chinese herbal medicines. [Conclusion] The herbal medicines can relieve the adverse effects caused by heat stress to blood biochemical indices via different metabolic pathways of ions and en- zymes.

Effect of Si on growth kinetics of intermetallic compounds during reaction between solid iron and molten aluminum

The effect of Si on the growth kinetics of intermetallic compounds during the reaction of solid iron and molten aluminum was investigated with a scanning electron microscope coupled with an energy dispersive X-ray spectroscope, and hot-dip aluminized experiments. The results show that the intermetallic layer is composed of major Fe2Al5 and minor FeAl3. The Al-Fe-Si ternary phase, rl/rg, is formed in the Fe2Al5 layer. The tongue-like morphology of the Fe2Als layer becomes less distinct and disappears finally as the content of Si in aluminum bath increases. Si in the bath improves the prohibiting ability to the growth of Fe2Als and FeAl3. When the contents of Si are 0, 0.5%, 1.0%, 1.5%, 2.0% and 3.0%, the activation energies of Fe2Al5 are evaluated to be 207, 186, 169, 168, 167 and 172 kJ/mol, respectively. The reduction of the activation energy might result from the lattice distortion caused by Si atom penetrating into the Fe2Al5 phase. When Si atom occupies the vacancy site, it blocks easy diffusion path and results in the disappearance of tongue-like morphology.

Regulatory Mechanism of Tea Polyphenols on Heat Stress in Animals

Teapolyphenols are the generic term of polyphenols in tea.Tea polyphenols are non-toxic and odorless with high oxidation resistance.Heat stress causes oxidative stress,which impairs the capacity of antioxidant defense system and immunity,thereby seriously affecting the production performance of animals.Teapolyphenols could reduce heatstress response in animals by scavenging harmful free radicals and increasing the activities of antioxidant enzymes.

Research Progress and Identification Method of Apple Stress Resistance

In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving drought-resistance, flood-re- sistance, salt-stress resistance, cold-hardiness and heat-resistance. In addition prospects of apple resistance research are proposed, as well.

Heat strain in chemical protective clothing in hot-humid environment:Effects of clothing thermal properties

Heat strain experienced by individuals wearing chemical protective clothing(CPC)is severe and dangerous especially in hot-humid environment.The development of material science and interdisciplinary studies including ergonomics,physiology and heat transfer is urgently required for the reduction of heat strain.The aim of this paper was to study the relationship among clothing thermal properties,physiological responses and environmental conditions.Three kinds of CPC were selected.Eight participants wore CPC and walked(4 km/h,two slopes with 5%and 10%)on a treadmill in an environment with(35±0.5)℃ and RH of(60±5)%.Core temperature,mean skin temperature,heart rate,heat storage and tolerance time were recorded and analyzed.Physiological responses were significantly affected by the clothing thermal properties and activity intensity in hot-humid environment.The obtained results can help further development of heat strain model.New materials with lower evaporative resistance and less weight are necessary to release the heat strain in hot-humid environments.

STUDY ON THE ANTI-TUMOR EFFICACY INDUCED BY HEAT SHOCK PROTEIN 70-PEPTIDE COMPLEXES DERIVED FROM TUMOR CELLS

OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P

Effects of different flui replacements on serum HSP70 and lymphocyte DNA damage in college athletes during exercise at high ambient temperatures

Purpose：The aim of this study was to investigate the effects of flui replacement by water or sports drinks on serum heat shock protein 70（HSP70） levels and DNA damage during exercise at a high ambient temperature.Methods：Ten male college athletes with an athletic career ranging from 6 to 11 years were recruited from Yonsei University.The subjects ran on a treadmill at 75% of heart rate reserve during 4 different trials：thermoneutral temperature at 18℃（T）,high ambient temperature at 32℃ without flui replacement（H）,high ambient temperature at 32℃ with water replacement（HW）,and high ambient temperature at 32℃ with sports drink replacement（HS）.During each condition,blood samples were collected at the pre-exercise baseline（PEB）,immediately after exercise（IAE）,and60 min post-exercise.Results：Skin temperature significant y increased during exercise and was significant y higher in H compared to T and HS at IAE.Meanwhile,serum HSP70 was significant y increased in all conditions at IAE compared to PEB and was higher in H compared to T at the former time point.Significant y increased lymphocyte DNA damage（DNA in the tail,tail length,tail moment） was observed in all trials at IAE compared to PEB,and attenuated DNA damage（tail moment） was observed in HS compared to H at IAE.Conclusion：Acute exercise elevates serum HSP70 and induces lymphocyte DNA damage.Fluid replacement by sports drink during exercise at high ambient temperature can attenuate HSP response and DNA damage by preventing dehydration and reducing thermal stress.

Cluster Analysis of Differentially Expressed Heat Stress Genes in Rat Jejunal Mucosal

[Objective] The aim was to study the heat stress mechanism of differen tially expressed genes in rat jejunal mucosal.[Method] Variable cluster analysis and cluster analysis of samples on the differentially expressed heat stress genes in rat jejunal mucosal were carried out with SAS software,and statistics of distribution of the differentially expressed genes on chromosomes were conducted.[Result] The differentially expressed genes were divided into seven categories,of which,the upregulated genes included three categories （i.e.：Category A：Hspa1a,Hspa1b,Hspb1,Hsph1,Dnaja4,Ahsa2 and P4ha1; Category B：Cyp1a2,Zbtb16,Gucy2g,Fgb,Cyp4a3 and Etv2; and Category C：Cyp1a2,Chac1 and Cyp4b1） and the down-regulated genes included four categories （i.e.：Category D：Tlr2,Noxo1,LOC286989 and Aspg; Category E：RGD1560395,Alb and BQ194726; Category F：Ccl4,Gzmk,Al228153,Anxa10,S100a9 and Ascl5; and Category G：Reg1a and Slc13a1）.The classification,function and reasons of differential expression for each gene category were analyzed.[Conclusion] Most of the three categories of up-regulated genes were related to the heat shock proteins; and most of the four categories of down-regulated genes were related to the immunity,providing reference for discussion of the heat stress mechanism.

A Review of Effects of Heat Stress on Substance and Energy Metabolism in Muscle

Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress.

Association of high expression in rat gastric mucosal heat shock protein 70 induced by moxibustion pretreatment with protection against stress injury

AIM:To study the effect of moxibustion on Zusanli or Liangmeng point on gastric mucosa injury in stress-induced ulcer rats and its correlation with the expression of heat shock protein 70 (HSP70). METHODS:Sixty healthy SD rats (30 males,30 females) were divided into control group,injury model group,Zushanli point group,Liangmeng point group. Stress gastric ulcer model was induced by binding cold stress method. Gastric mucosa ulcer injury (UI) index was calculated by Guth method. Gastric mucosa blood flow (GMBF) was recorded with a biological signal analyzer. Protein content and gene expression in gastric mucosal HSP70 were detected by immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR). Thiobarbital method was used to determine malondialdehyde (MDA) content. Gastric mucosal endothelin (ET) and prostaglandin E2 (PGE2) were analyzed by radioimmunoassay. RESULTS:High gastric mucosal UI index,high HSP70 expression,low GMBF and PGF2,elevated MDA and ET were observed in gastric mucosa of rats subjected to cold stress. Moxibustion on Zusanli or Liangmeng point decreased rat gastric mucosal UI index,MDA and ET. Conversely,the expression of HSP70,GMBF,and PGE2 was elevated in gastric mucosa after pretreatment with moxibustion on Zusanli or Liangmeng point. The observed parameters were significantly different between Zusanli and Liangmeng points. CONCLUSION:Pretreatment with moxibustion on Zusanli or Liangmeng point protects gastric mucosa against stress injury. This protection is associated with the higher expression of HSP70 mRNA and protein,leading to release of PGE2 and inhibition of MDA and ET,impairment of gastric mucosal index.

Effect of Thermal Defocusing on Backward Stimulated Raman Scattering in CH4

The conversion efficiency of stimulated Raman scattering （SRS） in CH4 is studied by using a single longitudinal mode second-harmonic Nd：YAG laser （532 nm, linewidth 0.003 cm^-1, pulse-width （FWHM） 6.5 ns）. Due to the heat release from vibrationally excited particles, SRS processes often suffer from the thermal defocusing effect （TDE）. In view of 6.5 ns laser pulse width is much shorter than the vibrational relaxation time of CH4 molecules, TDE can only affect the SRS processes afterwards. In the cases of low laser repetition, TDE will be not serious, because it will be removed by the thermal diffusion in Raman medium before the next pulse arrives. At the laser repetition rate 2 Hz, CH4 pressure 1.1 MPa and pump laser energy 95 mJ, the quantum conversion efficiency of backward first-Stokes （BS1） has attained 73%. This represents the highest first-stokes conversion efficiency in CH4. Furthermore, due to the relaxation oscillation, the BS1 pulses are narrowed to about 1.2 ns. As a result, the BS1 peak power turns out to be 2.7 times that of the pump. Its beam quality is also much better and is only slightly affected by TDE. This reason is that BS1 represents a wave-front-reversed replica of the pump beam, which can compensate the thermal distortions in Raman amplify process. Under the same conditions, but pump laser repetition rate as 10 Hz, the conversion efficiency of BS1 goes down to 36% due to TDE. From this study, we expect that a well-behaved 630 nm Raman laser may be designed by using a closed CH4/He circulating-cooling system, which may have some important applications.

Hormonal （Thyroxin, Cortisol） and Immunological （Leucocytes） Responses to Cistern Size and Heat Stress in Tunisia

This study was designed to determine the effects of heat stress on plasma leucocytes, Thyroxin （T4） and cortisol concentrations in dairy cows with small and large cistern under hot climate. This experiment was carried out in 2006, in North Tunisia, using a randomized block design per udder cistern size, using 60 Holstein cows. Cows were classified according to udder cistern size by ultrasonography as large-cisterned （44 ±13 cm2; LC） and small-cisterned （21 ± 8 cm2; SC）. The experiment was carried out in two different periods： spring （Apr. 5 （D1）） and summer （July 19 （D2）, Aug. 19 （D3） and Sept. 19 （D4））. On each test day, temperature and relative humidity data were registered hourly and cows＇ blood was sampled from the jugular vein to determine serum concentrates of cortisol and T4. Leucocytes （lyrnphocytes, eosinophils, neutrophils and monocytes） were counted differentially, and percentages of lymphocytes relative to total counted cells were calculated. Mean temperature-humidity index （THI） values were 62 ±2, 79 ±2, 84 ±2, and 77 ±1 in DI, D2, D3, and D4, respectively. Lymphocyte incidence relative to total cell counts and T4 concentrations were affected by test day （P 〈 0.001）. Lymphocytes （%） were significantly less in hotter months. During summer, T4 concentration at D2 （87.4 nmol/L） was higher relative to concentrations at D3 （42.8 nmol/L） and D4 （53.5 nmol/L）. T4 concentrations were higher （P 〈 0.01） in SC cows （67.7 ±0.1 nmol/L） compared to LC cows （52.7 ±0.1 nmol/L）. Cortisol concentration was effected neither by test day nor by cistern size. However, the decrease of lymphocyte concentration during summer compared to spring could be considered as an evidence of the suppression of cows＇ immune system under heat stress.

Laser Cleaning of Mirror Surface for Optical Diagnostic Systems of the International Thermonuclear Experimental Reactor

The development of cleaning optics and deposition-mitigating techniques is a key factor in the construction and operation of optical diagnostics in ITER. The cleaning of optical surface by pulsed radiation from a fiber laser is an effective method that can recover optical properties of the mirror surface. The possibility of cleaning metallic mirrors from films with complex composition by pulsed radiation from a fiber laser has been experimentally researched. It has been shown that the high initial reflection characteristics of optical elements can be recovered by choosing regimes of radiation effect on the deposited surface. Efficient cleaning is ensured by radiation with the power density of less than 107 W/cm2. At this relatively low power density, pollutions are removed in a solid phase and the thermal effect on the mirror is insignificant. Preliminary experiments of the metal mirrors cleaning by fiber laser radiation have demonstrated the possibility of hardware implementation techniques.

JNKs,insulin resistance and inflammation:A possible link between NAFLD and coronary artery disease

The incidence of obesity has dramatically increased in recent years.Consequently,obesity and associated disorders such as nonalcoholic fatty liver disease constitute a serious problem.Therefore,the contribution of adipose tissue to metabolic homeostasis has become a focus of interest.In this review,we discuss the latest discoveries that support the role of lipids in nonalcoholic fatty liver disease.We describe the common mechanisms(cJun aminoterminal kinases,endoplasmic reticulum stress,unfolded protein response,ceramide,lowgrade chronic inflammation)by which lipids and their derivatives impair insulin responsiveness and contribute to inflammatory liver and promote plaque instability in the arterial wall.Presenting the molecular mechanism of lipid activation of proinflammatory pathways,we attempt to find a link between nonalcoholic fatty liver disease,metabolic syndrome and cardiovascular diseases.Describing the common mechanisms by which lipid derivatives,through modulation of macrophage function,promote plaque instability in the arterial wall,impair insulin responsiveness and contribute to inflammatory liver and discussing the molecular mechanism of lipid activation of proinflammatory pathways,the key roles played by the proliferatoractivated receptor and liver X receptorα,nuclear receptorslipid sensors that link lipid metabolism and inflammation,should be emphasized.Further studies are warranted of antiinflammatory drugs such as aspirin,antiinterleukin6 receptors,immunemodulators(calcineurin inhibitors),substances enhancing the expression of heat shock proteins(which protect cells from endoplasmic reticulum stressinduced apoptosis),and anticJun aminoterminal kinases in welldesigned trials to try to minimize the high impact of these illnesses,and the different expressions of the diseases,on the whole population.

Reheating and thixoforging of ZK60+RE alloy deformed by ECAE

The two-pass equal channel angular extrusion (ECAE) process was introduced into strain-induced melt activation (SIMA) to predeform a ZK60 alloy with rare earth (RE) addition. Microstructure evolution of ECAE-formed ZK60+RE alloy during reheating was investigated. Furthermore, tensile properties of thixoforged components were determined. The results show that the SIMA process can produce ideal microstructures, and spheroidized solid particles with little entrapped liquid can be obtained. With prolonging holding time, the size of solid particles increases and the degree of spheroidization is improved. The tensile properties of the thixoforged ZK60+RE samples are close to those of two-pass ECAE-formed samples.