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.

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

A series of MoN/HZSM-5 and transition metal modified MoN/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 MoN loading on HZSM-5, transition metal (Fe, Ce, La, Cu, Cr) modification of MoN/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.

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 KPO 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.

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.

[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.

[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.

[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.

[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.

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.

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.

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.

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.

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.

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.

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 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.

[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.

[Research on the autofluorescence spectroscopy in rats doing medium-intensity exercise].

The laser-inducted fluorescence spectrum technology (LIF) was used for the first time to study the autofluorescence spectral characteristics of the heart, kidney, liver, fat, foreleg muscle, hind leg soleus muscle and musculus gastrocnemius of the rat performing motion exercises. The wavelength of the excitation light used during the measurement was in the range of 250-650 nm and the emission wavelength was 300-700 nm. When comparing the three-dimensional fluorescence spectra of the control group with those of the four groups of different motion states, a specific fluorescence peak related to the motion and located in the area where the excitation wavelength was (340 +/- 10) nm and the emission wavelength was (460 +/- 10) nm was found mainly in the spectra of the soleus muscle.

[An optical mapping system based on spectral shift of voltage-sensitive dyes].

Recently, non-invasive optical methods to monitor transmembrane electrical potential using voltage sensitive dyes have been applied widely in the studies of normal and pathological heart rhythms and defibrillation. In the present paper, the authors measured the excitation and the emission spectra of the voltage-sensitive dyes di-4-ANEPPS bound to phospholipid bilayer membranes. And according to the spectral shift of di-4-ANEPPS, the authors presented an optical mapping system combining a DALSA CCD camera and a LED light source.

[Spectral study of voltage sensitive dye di-4-ANEPPS].

This study investigated the absorption spectrum and the fluorescence spectrum of rabbit hearts stained with the voltage sensitive dye (di-4-ANEPPS). The results suggested that the optical absorption of tissue with the dye was higher than that of the control group, and there were significant differences between the experimental group and control group in the range of 450-550 nm. It was also indicated that the maximum absorption peak of the dye in tissues was at (479.

Construction and biological characterization of artificial recombinants between a wild type flavivirus (Kunjin) and a live chimeric flavivirus vaccine (ChimeriVax-JE).

Although the theoretical concern of genetic recombination has been raised related to the use of live attenuated flavivirus vaccines [Seligman, Gould, Lancet 2004;363:2073-5], it has little foundation [e.g., Monath TP, Kanesa-Thasan N, Guirakhoo F, Pugachev K, Almond J, Lang J, et al.

A single M protein mutation affects the acid inactivation threshold and growth kinetics of a chimeric flavivirus.

Numerous viruses of the Flaviviridae family, including dengue, yellow fever, Japanese encephalitis, and West Nile, cause significant disease in humans and animals. The structure and function of the molecular components of the flavivirus envelope are therefore of significant interest. To our knowledge, a membrane (M) protein mutation which affects the pH at which flavivirus particles are inactivated in vitro has never been reported.