1.Numerical Simulation on Phase Change Heat Transfer Process of Biological Tissue in Cryosurgery
Juan SHI ; Zhenqian CHEN ; Mingheng SHI
Space Medicine & Medical Engineering 2006;0(03):-
Objective To study the mechanism of heat transfer by simulating a complete freezing-thawing process of biological tissue.Methods A numerical model of phase change heat transfer in biological tissue was developed with consideration of the difference of thermophysical properties for normal biological tissue and tumor.The biological tissue was assumed as a porous media.The different thermophysical properties between tissue framework and tissue fluid(as water in tissue,etc) were considered.An apparent heat capacity method was applied to solve the phase change heat transfer problem.Results It was showed that the temperature of biological tissue decreased more quickly during the freezing process when the initial cryoprobe temperature was lower and the cooling-rate of cryoprobe was faster.The temperature of biological tissue increased more quickly with faster warming-rate of cryoprobe in the thawing process.It was also showed that the porosity,blood perfusion rate and metabolic heat generation of the biological tissue had effects on tissue freezing temperature in biological tissue.Conclusion To study the thermal process of biological tissue in cryosurgery will be very helpful for further application in cryosurgery.
2.Principle of biological samples selection in comparative proteomics of silicosis.
Juan-juan CHEN ; Mao-ti WEI ; Shi-xin WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2009;27(10):639-1 p following 640
Humans
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Proteomics
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methods
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Silicosis
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metabolism
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Specimen Handling
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methods
3.Preliminary application of ultrasound real-time elastography in diagnosis of thyroid diffuse disease
Xiuying SHI ; Hong AI ; Juan WANG
Chinese Journal of Ultrasonography 2011;20(6):515-518
Objective To explore the diagnosis value of ultrasound real-time elastography in thyroid diffuse diseases.Methods Eleven elastic quantitative parameters of 123 patients with thyroid diffuse diseases and 42 healthy volunteers obtained from the ultrasound real-time elastography were analyzed with principal components analysis to attain a comprehensive evaluation value which was named stiffness index(SI),reflecting the organization elastic information of different thyroid diffuse diseases.SI among each group was compared by ANOVA.Results Chronic lymphocytic thyroiditis SI was 86.37±20.45,subacute thyroiditis SI was 86.14±19.95,primary hyperthyroidism SI was 54.68±21.69,normal control group SI was 41.34±15.59,respectively.The SI between chronic lymphocytic thyroiditis,subacute thyroiditis,primary hyperthyroidism and normal controls had significant statistical differences (P<0.05),the SI between primary hyperthyroidism and chronic lymphocytic thyroiditis,subacute thyroiditis had significant statistical differences (P<0.05),the SI between chronic lymphocytic thyroiditis and subacute thyroiditis had no significant statistical difference (P>0.05).Conclusions Ultrasound real-time elastography could indirectly reflect the stiffness information of thyroid lension tissue and have a certain degree of diagnosis value in thyroid diffuse disease.
4.Macrophage migration inhibitory factor and hypothalamo-pituitary-adrenal function during sepsis inchildren
Liuhong SHI ; Ying WANG ; Juan QIAN
International Journal of Pediatrics 2011;38(6):572-575
The hypothalamo-pituitary-adrenal (HPA) axis modulates the inflammatory response during sepsis.Macrophage migration inhibitory factor (MIF) is a unique cytokine and critical mediator of host defenses in sepsis and septic shock.MIF counteracts the anti-inflammatory activity of glucocorticoid (GC).The interaction of GC and MIF might cause adrenal insufficiency.MIF could be a valuable clinical marker of adrenal insufficiency in sepsis.
6.Serum osteocalcin in patients with rheumatoid arthritis
Chinese Journal of General Practitioners 2005;0(09):-
0.05).There was a significant positive correlation between serum osteocalcin and ESR in female patients with RA aged less than 50 years (P
7.Construction and Functional Analysis of a Synthetic Wound-and Hormone-inducible Promoter ocs/mas
China Biotechnology 2006;0(07):-
The use of optimal regulatory sequences for simultaneous expression of the transgenes might play a significant role in engineering plants with increased disease and insect resistance.The plant expression vector pOMS-GUS,which contained the GUS gene under the control of a chimeric promoter based upon the mannopine synthase(mas)promoter and the octopine synthase(ocs)enhancer,was constructed.Used as control,another vector pMAS-GUS,carried the GUS gene driven by only the mas promoter.The two vectors were introduced into tobacco plants by Agrobacterium-mediated transformation.Fluorometric assays for GUS activity and reverse transcription-polymerase chain reaction(RT-PCR)analysis revealed that GUS gene expressed weakly with untreated transgenic tobacco while the level of GUS activity increased steadily after 1 h subjected to wounding.The expression of the mas and ocs/mas promoters was induced a further 1.8-fold and 5.7-fold,respectively.SA(1 mmol/L)or MJ(250 ?mol/L)treatment also caused a large induction of the ocs/mas chimeric promoter;And the application of SA in combination with MJ(1 mmol/LSA & 250 ?mol/L MJ)produced an additive effect that exceeded the wounding response.The results showed that the ocs/mas chimeric promoter is a strong inducible promoter that can be activated by various stresses.The chimeric promoter should have utility in development of disease and insect resistant transgenic crops.
8.Changes of serum estradiol in newborns and the relationship with retinopathy of prematurity
Juan DU ; Wenjing SHI ; Chao CHEN
Chinese Journal of Perinatal Medicine 2010;13(6):478-482
Objective To observe the serum estradiol level in newborns at different gestational age and the infants with retinopathy of prematurity (ROP), and explore the relationship between these changes and ROP. Methods A total of 178 newborns hospitalized in the Children's Hospital of Fudan University were enrolled in the study. They were divided into three groups based on the gestational age, < 32 weeks group, 32-37 weeks group and term group. The three groups were further divided into non-oxygen and oxygen subgroups. Infants with birth weight less than 2000 g were evaluated for ROP and those diagnosed as ROP were under ROP group (n=6). Serum estradiol levels were measured every week from birth to discharge with radioimmunoassay. Results Serum estradiol levels of newborns quickly declined after birth. In the non-oxygen subgroups, serum estradiol levels in 32 ~ 37 weeks group were remarkably higher than those of term group in the first week [(3506±1376) pmol/L vs (1717±179) pmol/L,P<0. 05] and the third week [(1431±92) pmol/L vs (996±102) pmol/L, P<0. 05]; Serum estradiol levels in <32 weeks group was only remarkably higher than those of term group in the first week [(3173± 1369) pmol/L vs (1717± 179) pmol/L,P<0. 05]; Serum estradiol level in the <32 week group was (560±355) pmol/L, lower than that in the 32-37 weeks group [( 1124 ± 128) pmol/L] (P<0. 05). There was no difference of serum estradiol levels in the oxygen and non-oxygen subgroups of the same group. There was no significant difference of serum estradiol levels between the ROP group and <32 weeks group. Serum estradiol levels in ROP group was lower than that of premature group without ROP at 29 and 32-36 weeks of corrected gestational age, but no statistical difference was shown. Conclusions Very low serum estradiol level in premature infants may be related to the development of ROP, but further clinical studies are required.