Study on the Correlation between Metabolism, Insulin Sensitivity and progressive weight loss change in Type-2 Diabetes.

OBJECTIVE: To observe the changes of lipid metabolism, blood glucose level and insulin sensitivity in patients with Type-2 diabetes after progressive weight loss of their body weight, so as to lay a theoretical foundation for diabetes treatment and education in the future. METHODS: One hundred obese patients with Type-2 diabetes (BMI ≥ 25 kg/m2) who visited the endocrinology department of our hospital from April 2017 to April 2018 were given diabetes health education, diabetic diet, exercise and other measures to control their weight. The changes of blood glucose, blood lipid, insulin level and insulin release test before weight loss (T1), and at the time points of weight loss reached 5% (T2), 10% (T3) and 15% (T4) were recorded respectively to understand the influence of progressive weight loss on relevant indexes of patients. RESULTS: With the decrease of body weight, the differences of TC, TG, LDL-C and HDL-C at different weight loss points were significant (p < 0.05), and the changes of fasting blood glucose in 5% and 10% weight loss were significant (p = 0.02). The 2h postprandial blood glucose showed the most significant difference when the weight loss reached 15% (p = 0.00). There was no statistical difference in the change of glycosylated hemoglobin among different weight loss points (p = 0.08). When the weight loss reached 10%, the blood insulin level was significantly lower than that before the weight loss, while the insulin level was not significantly changed when the weight loss reached 15%, but the peak of secretion was shifted forward. It is suggested that insulin sensitivity gradually increases with weight loss. CONCLUSION: Obese patients with Type-2 diabetes can benefit from weight loss, with abnormal blood glucose and lipid metabolism improved, insulin resistance relieved, and insulin sensitivity increased.

Chinese men living in urban areas of Shijiazhuang, Hebei at higher risk of overweight or obesity.

OBJECTIVE: The prevalence of overweight/obesity in China has increased dramatically in recent years; being overweight/obese can increase the risk of type 2 diabetes and cardiovascular disease. The purpose of this study was to determine the population in China at high risk of being overweight or obese, to explore the relationships between various relevant factors and overweight/obesity, and to identify preventive efforts for high-risk populations. METHODS: We administered a questionnaire survey among a group of 536 social workers in Shijiazhuang City in 2017. We used the Pearson chi-square test, Spearman's rho test, multivariate linear regression, univariate and multivariate logistic regression, and receiver operating characteristic curve analysis to investigate factors that influence overweight/obesity. RESULTS: The prevalence of overweight/obesity was 13.7% among the study participants. Urban residence, eating speed, number of daily meals, overeating, and a high-fat diet were associated with overweight/obesity. In multivariate linear regression analysis, overweight/obesity was correlated with sex, urban residence, eating speed, number of daily meals, and a high-fat diet. CONCLUSION: Among all influencing factors, dietary factors, place of residence, and sex were most closely related to being overweight/obese. Furthermore, living in an urban area and male sex were independent risk factors for being overweight/obese.

Selective preparation of 1-hydroxy-3,6-dioxabicyclo[3.2.1]octan-2-one by fast pyrolysis of cellulose catalyzed with metal-loaded nitrided HZSM-5.

1-Hydroxy-3,6-dioxabicyclo[3.2.1]octan-2-one (LAC) is a valuable chiral compound, which can be prepared from catalytic fast pyrolysis (CFP) of cellulose. In this study, nitrided HZSM-5 (N-HZSM-5) and metal-loaded N-HZSM-5 were prepared for CFP of cellulose to selectively produce LAC. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and lab-scale experiments were conducted to explore LAC preparation affected by nitridation and metal modification of HZSM-5, pyrolytic reaction temperature and catalyst-to-cellulose (CA/CL) ratio. The Py-GC/MS experiments obtained the maximal LAC yield of 7.48 wt% with the corresponding selectivity of 30.33% under 5 wt% Mg loaded N-HZSM-5 (5%Mg/N-HZSM-5) with the CA/CL ratio of 6 at 350 °C, compared with those of 1.22 wt% and 2.87% in non-catalytic process. Moreover, lab-scale experiments resulted in the LAC yield and selectivity of 6.69 wt% and 26.18% under the conditions of 5%Mg/N-HZSM-5, CA/CL ratio of 4 and 400 °C. The results demonstrated the promising catalytic performance of Mg/N-HZSM-5 on LAC production from CFP of cellulose.

Monocyclic aromatic hydrocarbons production from catalytic cracking of pine wood-derived pyrolytic vapors over Ce-Mo2N/HZSM-5 catalyst.

A series of Mo2N/HZSM-5 and transition metal modified Mo2N/HZSM-5 catalysts were prepared for the catalytic upgrading of pine wood-derived pyrolytic vapors for the selective production of monocyclic aromatic hydrocarbons (MAHs), while restraining the formation of polycyclic aromatic hydrocarbons (PAHs). Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were performed to determine the effects of several factors on selective MAHs production, including Mo2N loading on HZSM-5, transition metal (Fe, Ce, La, Cu, Cr) modification of Mo2N/HZSM-5, pyrolysis temperature, and catalyst-to-biomass ratio. In addition, quantitative experiments were conducted to determine the actual yields of major aromatic hydrocarbons and the source of aromatic hydrocarbons from basic biomass components. Results indicated that among the various catalysts, the Ce-10%Mo2N/HZSM-5 exhibited the best performance on promoting the formation of MAHs and restraining the generation of PAHs. Under the optimal conditions, the actual yields of MAHs and PAHs from Ce-10%Mo2N/HZSM-5 catalytic process were 99.8mg/g and 7.5mg/g, while those from HZSM catalyst were only 77.2mg/g and 23.7mg/g respectively. Furthermore, the possible catalytic mechanism of the Ce-Mo2N/HZSM-5 catalyst was proposed based on the catalyst characterization.

Catalytic Fast Pyrolysis of Biomass Impregnated with Potassium Phosphate in a Hydrogen Atmosphere for the Production of Phenol and Activated Carbon.

A new technique was proposed to co-produce phenol and activated carbon (AC) from catalytic fast pyrolysis of biomass impregnated with K3PO4 in a hydrogen atmosphere, followed by activation of the pyrolytic solid residues. Lab-scale catalytic fast pyrolysis experiments were performed to quantitatively determine the pyrolytic product distribution, as well as to investigate the effects of several factors on the phenol production, including pyrolysis atmosphere, catalyst type, biomass type, catalytic pyrolysis temperature, and catalyst impregnation content. In addition, the pyrolytic solid residues were activated to prepare ACs with high specific surface areas. The results indicated that phenol could be obtained due to the synergistic effects of K3PO4 and hydrogen atmosphere, with the yield and selectivity reaching 5.3 wt% and 17.8% from catalytic fast pyrolysis of poplar wood with 8 wt% K3PO4 at 550°C in a hydrogen atmosphere. This technique was adaptable to different woody materials for phenol production. Moreover, gas product generated from the pyrolysis process was feasible to be recycled to provide the hydrogen atmosphere, instead of extra hydrogen supply. In addition, the pyrolytic solid residue was suitable for AC preparation, using CO2 activation method, the specific surface area was as high as 1,605 m2/g.

Change of short-term memory effect in acute ischemic ventricular myocardium: a computational study.

The ionic mechanism of change in short-term memory (STM) during acute myocardial ischemia has not been well understood. In this paper, an advanced guinea pig ventricular model developed by Luo and Rudy was used to investigate STM property of ischemic ventricular myocardium. STM response was calculated by testing the time to reach steady-state action potential duration (APD) after an abrupt shortening of basic cycling length (BCL) in the pacing protocol. Electrical restitution curves (RCs), which can simultaneously visualize multiple aspects of APD restitution and STM, were obtained from dynamic and local S1S2 restitution portrait (RP), which consist of a longer interval stimulus (S1) and a shorter interval stimulus (S2). The angle between dynamic RC and local S1S2 RC reflects the amount of STM. Our results indicated that compared with control (normal) condition, time constant of STM response in the ischemic condition decreased significantly. Meanwhile the angle which reflects STM amount is less in ischemic model than that in control model. By tracking the effect of ischemia on intracellular ion concentration and membrane currents, we declared that changes in membrane currents caused by ischemia exert subtle influences on STM; it is only the decline of intracellular calcium concentration that give rise to the most decrement of STM.

[Synthesis of folate receptor-targeted nanoprobe for detection of cancer cells and its spectral analysis].

Folate receptor (FR) is particularly upregulated in many epithelial cancer cells membrane and limited distribution is found in normal tissues. In the present work, the folic acid protected gold nanoparticles (FA-GNPs) were synthesized by a simple and quick method, in which chloroauric acid (HAuCl4) was reduced by sodium borohydride (NaBH4) in the presence of FA is used as stabilizer. UV-Visible spectroscopy and transmission electron microscopy (TEM) were used to characterize the shape and size distribution of the produced FA-GNPs. X-ray photoelectron spectroscopy and cell experiment were employed to confirm the immobilization of FA and GNPs. The results showed that FA-GNPs have a good size distribution in the 3-5 nm diameter range. Moreover, it is very stable even in solution with high concentration of salt (up to 3.5% NaCl), and even high speed centrifuges of 25 000 r x min(-1) could not cause aggregation. The nanoparticles could be used to detect cancer cells.

[New photosensitiser 5-ALA-GNPs for photodynamic therapy and its spectral analysis].

A novel strategy by means of poly diallyl dimethylammonium chloride (PDDA) was used to make highly mono-dispersed positively charged gold nanoparticles, and 5-ALA was immobilized onto the gold nanoparticles through electrostatic interaction. The conjugation of 5-aminolevulinic acid (5-ALA) and gold nanopartilces were characterized by the integrated tools of resonance Rayleigh scattering (RRS), UV-Vis absorption spectra, transmission electron microscopy (TEM) and laser light scattering. The results demonstrated that 5-ALA can be attached onto positively charged gold nanoparticles. This new photosensitizer is significant for enhancing PDT efficacy clinically.

[Steady-state spectroscopy on complementary tissue structural and functional information extraction].

Steady-state spectroscopy is prevailing for complementary tissue structural and functional information extraction The goal of the present study is to experimentally validate the merit of this technique for optical properties and intrinsic fluorescence extraction from tissue mimicking phantoms. Phantom studies were carried out in which HbO2 was used as absorber, polystyrene sphere was used as scatterer, and stilbene was used for fluorescence emission Two sets of phantoms corresponding to two absorption levels and one scattering level were made, and 4 fluorophore concentrations were titrated in each set. The results indicate that both optical properties and intrinsic fluorescence can be extracted with high accuracy, implying that it's feasible to extract complementary structural and functional information with steady-state spectroscopy.

[A study on blood flow measurement by diffuse correlation spectroscopy].

Blood flow plays an important role in clinical diagnosis and treatment, and noninvasive measurement of blood flow is the expectation of both doctors and patients. In the present work, the authors employed near-infrared diffuse correlation spectroscopy (DCS) method to measure blood flow noninvasively. The relationship between speckle intensity fluctuations of the scattering light and moving blood cells in tissue was theoretically analyzed. A theoretical model and blood flow measurement system were built. Blood flow was derived by calculating the electric field temporal autocorrelation function of speckle on tissue surface. Forearm blood flow was measured in healthy human subject during cuff inflation and deflation. Experimental results show that noninvasive blood flow measurement by this system is feasible. The results also suggest that this approach can provide blood flow information throughout the whole depth profile of the tissue.

Characterization of the RepliVax platform for replication-defective flavivirus vaccines.

RepliVax, a novel replication-defective vaccine platform has recently been described as a suitable means of generating potent vaccines targeting flaviviruses. In this study, we directly compared attenuation, immunogenicity and efficacy of several prototype RepliVax constructs to available, well characterized live attenuated (LAV) and inactivated (INV) flavivirus vaccine controls in mice and hamsters. Other important aspects of general mechanisms and properties of RepliVax vaccines were also studied. The prototypes were found to be nonpathogenic in sensitive suckling mouse neurovirulence tests, and highly immunogenic and efficacious in mice and hamsters, with evidence that immunogenicity can be comparable to LAV controls in terms of both magnitude and durability of response. Our data also suggest that choice of inoculation route can be beneficial for maximizing RepliVax immunogenicity. Additionally, different vaccine constructs can be administered as cocktail formulations without compromising immunogenicity of individual components. RepliVax constructs were determined to induce a Th1 biased immune response, similar to LAVs, and different from INV inducing a Th2 type response. The results presented validate the utility of the RepliVax platform for development of novel flavivirus vaccines.

Role of intracellular calcium dynamics in the short-term memory in CVM model: a simulation study.

Many experimental studies claimed that, short-term memory, an intrinsic property of paced cardiac myocytes, has been regulated by either intracellular calcium cycling or membrane ionic currents, manifested by a time constant of cellular action potential duration (APD) restitution. Although both factors play important roles in short-term memory, their respective effects have not been well understood currently. In this study, we used an ionic model of canine ventricular myocytes (CVM) to investigate the effect of calcium release from the sacroplasm reticulum (SR), as well as the effect of L-type calcium current, on cardiac short-term memory. We calculated short-term memory response by testing the time to reach steady-state APD after an abrupt shortening of basic cycling length (BCL) in pacing protocol. Our results indicated that as the release of calcium from SR was gradually prevented, short-term memory response decreased, while the blockade of L-type calcium channel had little effect on short-term memory. Finally, we declared that the amount of intracellular calcium released from SR affected short-term memory of cardiac tissues more than that of L-type calcium channel.

Expression pattern of the ASPP family members in endometrial endometrioid adenocarcinoma.

BACKGROUND: Apoptosis-stimulating protein of p53 (ASPP) family members can stimulate the apoptotic function of p53 but have no impact on its cell cycle arrest function. MATERIAL AND METHODS: The expression pattern of the ASPP family consisting of ASPP1, ASPP2, and iASPP was examined by immunohistochemistry in 45 formalin-fixed and paraffin-embedded endometrial endometrioid adenocarcinoma (EEA) specimens and 26 normal endometrial tissue (NET) samples. RESULTS: The expression rates of ASPP1 and ASPP2 in EEA were significantly lower than those in NET (p < 0.05). However, the iASPP expression rate in EEA was statistically higher in contrast to NET (p < 0.05). Expression of ASPP1 and iASPP in EEA had no correlation with any clinicopathological features (p > 0.05). iASPP was associated with grade, invasion, and lymph node metastasis (p < 0.05). CONCLUSIONS: It is a novel finding that the expression pattern of the ASPP family members has respective pathological and clinical implications in EEA, and iASPP might be a candidate target for EEA therapy.

Expression of PSCA, PIWIL1, and TBX2 in endometrial adenocarcinoma.

BACKGROUND: Endometrial cancer is the 4th most common gynecological cancer. The expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1), and T-box 2 (TBX2) in endometrial cancer remains to be elucidated. MATERIAL AND METHODS: The expression of PSCA, PIWIL1, and TBX2 was examined using the streptavidin-peroxidase method in 64 endometrial endometrioid adenocarcinoma (EAC) and paired normal endometrium (NE) samples from the Shaanxi Province in China. RESULTS: Positive expression rates of PSCA, PIWIL1, and TBX2 were 75% (48/64), 25% (16/64), and 56% (36/64), respectively in EACs, but 5% (3/64), 6% (4/64), and 2% (1/64), respectively in NEs. The difference was statistically significant (p < 0.05). PSCA was positively correlated with TBX2 (p = 0.003) but not PIWIL1 (p = 0.188). PIWIL1 was positively correlated with TBX2 (p = 0.003). PSCA was positively correlated with age, tumor grade, and lymph node metastasis (p < 0.05). TBX2 had an association with lymph node metastasis (p = 0.014). PIWIL1 was not associated with clinicopathological features (p > 0.05). CONCLUSIONS: We report the first analysis of PSCA, PIWIL1, and TBX2 expression in EAC. Our findings suggest that PSCA and TBX2 might be candidate targets for cancer therapy, and have helped us further understand the carcinogenesis of endometrial cancer.

Effects of electrical heterogeneity on transmural reentry during acute global ischemia.

Ventricular arrhythmias are commonly observed in patients with ischemia. It is reported that the electrophysiological changes evoked by ischemia are greater in the epicardium than in the endocardium. To investigate the effects of this heterogeneity on transmural reentry, the computer simulation method is used. A two-dimensional model which can reproduce the endocardial, epicardial and middle cell types, approximate the ischemic characteristics and distribution of the ischemic severity is developed by setting different ratios of the maximum conductance of the rapid and slow inward rectifier potassium currents and considering the three major component conditions of acute ischemia at the ionic level. The results demonstrate that action potentials of the ischemic cells have elevated resting potential, shortened duration, slowed upstroke and declined amplitude. Conduction velocity is much more depressed in the epicardium because of the ischemia-induced transmural gradient of excitability. The epicardially initiated activation has wider vulnerable window and more possibility to cause unidirectional propagation even reentry. Dispersion of the excitability is proposed to be the underlying mechanism.

Expression of PSCA, PIWIL1 and TBX2 and its correlation with HPV16 infection in formalin-fixed, paraffin-embedded cervical squamous cell carcinoma specimens.

The purpose of our study was to investigate the expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1) and T-box 2 (TBX2) and its correlation with HPV16 infection in cervical squamous cell carcinoma (CSCC). HPV16 was detected by amplifying the HPV16 E7 gene by the polymerase chain reaction (PCR) method, and the expression of PSCA, PIWIL1, TBX2 and HPV16 E7 in 59 CSCCs and matched adjacent normal cervix (MANC) was examined by the streptavidin-peroxidase (SP) method. Fifty-two CSCCs and MANC specimens that were positive for the E7 gene and the E7 protein were identified as infected with HPV16 and included in present study. The rate of infection with HPV16 in CSCC was 52% (27/52), but that in matched adjacent normal cervix (MANC) samples was 4% (2/52). Infection with HPV16 was found to be statistically more frequent in CSCC (P = 0.000). The expression rates of PSCA, PIWIL1 and TBX2 in MANC were 6% (3/52), 8% (4/52) and 2% (1/52), respectively, but those in CSCC were 62% (32/52), 75% (39/52) and 52% (27/52), respectively. Higher expression rates of PSCA, PIWIL1 and TBX2 were observed in CSCC than in MANC (P = 0.000). HPV16 had a statistical positive correlation with PSCA, PIWIL1 and TBX2 in CSCC (P < 0.05). The increased expression of PSCA, PIWIL1 and TBX2 had no correlation with the patient's age or histological grade P > 0.05). The elevated expression of PSCA and PIWIL1 was associated with invasion of CSCC (P < 0.05). Up-regulated expression of TBX2 had a positive association with lymph node metastasis (P = 0.014). These findings demonstrate for the first time the expression of PSCA, PIWIL1 and TBX2 in CSCC. Their correlation with HPV16 might provide new basic information for investigating the molecular mechanism of HPV and help us to deepen our understanding of the interaction between HPV16 and host cells the carcinogenesis of CSCC.

Direct random insertion of an influenza virus immunologic determinant into the NS1 glycoprotein of a vaccine flavivirus.

A live chimeric vaccine virus against Japanese encephalitis (JE), ChimeriVax-JE, was used to define methods for optimal, random insertion of foreign immunologic determinants into flavivirus glycoproteins. The conserved M2e peptide of influenza A virus was randomly inserted into the yellow fever-specific NS1 glycoprotein of ChimeriVax-JE. A technique combining plaque purification with immunostaining yielded a recombinant virus that stably expressed M2e at NS1-236 site. The site was found permissive for other inserts. The insertion inhibited NS1 dimerization in vitro, which had no significant effect on virus replication in vitro and immunogenicity in vivo. Two different NS1-specific monoclonal antibodies and a polyclonal antibody efficiently recognized only the NS1 protein dimer, but not monomer. Adaptation of the virus to Vero cells resulted in two amino acid changes upstream from the insert which restored NS1 dimerization. Immunized mice developed high-titer M2e-specific antibodies predominantly of the IgG2A isotype indicative of a Th1-biased response.

The relationship between HPV16 and expression of cyclooxygenase-2, P53 and their prognostic roles in esophageal squamous cell carcinoma.

OBJECTIVES: This study aimed to investigate the relationship between human papillomavirus type 16 (HPV16) and expression of cyclooxygenase-2 (COX-2), P53 in esophageal squamous cell carcinoma (ESCC), which has not yet been elucidated. METHODS: HPV16 was detected by amplifying the HPV16 E6 gene by the PCR method, and the expression of COX-2, P53 protein in 69 ESCCs and 32 normal esophageal mucosa (NEM) from Shaanxi Province was examined by the streptavidin-peroxidase method. Estimation of overall survival by HPV16, COX-2, and P53 was calculated with the Kaplan-Meier method and analyzed with the log-rank test. RESULTS: The infection rate of HPV16 in ESCCs (35 of 69, 50.7%) was significantly higher than that in NEMs (two of 32, 6.25%) (P<0.01). The expression rate of COX-2 in ESCCs (44 of 69, 63.8%) was higher than that in NEMs (two of 32, 6.25%) (P<0.01). The expression intensity of COX-2 expression had statistical difference in histological grade (R = 0.4453, P = 0.0019), tumor stage (R = 0.438, P = 0.000), and metastasis (R = 0.417, P = 0.002). P53 expression rate was 49.3% (34 of 69) in ESCC and 18.8% (six of 32) in NEMs. The expression rate of P53 proteins in ESCC was statistically higher than that in N67EMs (P = 0.0037). The infection of HPV16 had inverse correlation with the overexpression of COX-2 in ESCCs (R = -0.321, P = 0.008). The HPV16 DNA in ESCC had no statistical correlation with P53 protein (R = -0.014, P = 0.9055) and the elevated expression of COX-2 had positive correlation with P53 protein in ESCC (R = 0.441, P = 0.000). No statistical correlation was observed between the infection of HPV16 and clinicopathological features in ESCCs including sex, age, tumor stage, and lymph node metastasis, respectively (P>0.05). The COX-2 had no statistical correlation with sex and age (P>0.05), but had association with tumor stage and lymph node metastasis, respectively (P<0.05). The expression of P53 protein had significant association with lymph node metastasis (P = 0.0005), but not with sex, age, and tumor stage, respectively (P>0.05). The overexpression of COX-2, infection of HPV16, and P53 protein in ESCC were not correlated with survival during the 5-year follow-up period (P>0.05). CONCLUSION: We first concluded that the increased expression of COX-2 had inverse correlation with HPV16 in ESCC. COX-2, HPV16, and P53 had no significant effect on the survival of patients with ESCC. These observations might help us to further understand the significant association between HPV16 and other molecules involved in the carcinogenesis and progression of ESCC.

The relationship between cyclooxygenase-2, CD44v6, and nm23H1 in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal cancer is the fourth most prevalent malignancy in China. The relationship between COX-2, CD44v6, and nm23H1 in esophageal squamous cell carcinoma (ESCC) remains unclear. MATERIAL AND METHODS: Expression of COX-2, CD44v6, and nm23H1 was examined, using the streptavidin-peroxidase method, in 82 ESCC and 30 normal esophageal mucosa (NEM) samples from the Shaanxi Province in China. RESULTS: The positive rates of COX-2, CD44v6, and nm23H1 were 73.2% (60/82), 64.6% (53/82), and 24.4% (31/82), respectively in ESCC, but 6.7% (2/30), 3.3% (1/30), and 90% (27/30), respectively in NEMs. There was a statistically significant difference between NEMs and ESCCs (p < 0.05). Expression of COX-2 showed a positive statistical correlation with expression of CD44v6 (r = 0.4732, p < 0.0001), and an inverse correlation with nm23H1 (r = -0.3226, p = 0.0035). Expression of COX-2, CD44v6, and nm23H1 had no significant correlation with gender or age (p > 0.05), but increased expression of COX-2 and CD44v6 showed statistical correlation with invasion and lymph node metastasis, respectively (p < 0.05). Decreased expression of nm23H1 was statistically correlated with lymph node metastasis (p = 0.0007) but had no correlation with invasion (p = 0.8221). CONCLUSIONS: This is the first report of a significant correlation between COX-2, CD44v6, and nm23H1 in ESCC. This knowledge might help us to further understand the molecular mechanisms of carcinogenesis and progression of ESCC.

[Research on the autofluorescence spectroscopy of heart tissues].

The present study investigated the three-dimensional spectra and emission spectra of the autofluorescence of rabbit hearts. The results suggested that the three-dimensional spectra of the iced atria and ventricle were observed more evidently different from that of the fresh tissue compared to the main artery, which indicated that the amount of flavins and NADHs changed. Also, the atria, ventricle and main artery have different specific excitation spectra at the wavelength of 340 nm. The main fluorescence peaks were of NADH (at about 460 nm), collagen and elastin (at about 290-400 nm). The Gauss spectra of atria and ventricle were different in the peak value, relative intensity and half width. So the ratios of fluorescence intensities of peaks may be used to distinguish different heart tissues. Furthermore, a phenomenon was firstly uncovered that the autofluorescence intensity of NADH in ventricle decays with the time of death and it could be a useful method for the estimation of postmortem interval.