Identification of heparin samples that contain impurities or contaminants by chemometric pattern recognition analysis of proton NMR spectral data.

Chemometric analysis of a set of one-dimensional (1D) (1)H nuclear magnetic resonance (NMR) spectral data for heparin sodium active pharmaceutical ingredient (API) samples was employed to distinguish USP-grade heparin samples from those containing oversulfated chondroitin sulfate (OSCS) contaminant and/or unacceptable levels of dermatan sulfate (DS) impurity. Three chemometric pattern recognition approaches were implemented: classification and regression tree (CART), artificial neural network (ANN), and support vector machine (SVM). Heparin sodium samples from various manufacturers were analyzed in 2008 and 2009 by 1D (1)H NMR, strong anion-exchange high-performance liquid chromatography, and percent galactosamine in total hexosamine tests.

Regulation of VEGF-induced endothelial cell migration by mitochondrial reactive oxygen species.

Endothelial migration is a crucial aspect of a variety of physiologic and pathologic conditions including atherosclerosis and vascular repair. Reactive oxygen species (ROS) function as second messengers during endothelial migration. Multiple intracellular sources of ROS are regulated by cellular context, external stimulus, and the microenvironment.

An ab initio calculation study of silicon and carbon binary clusters C7Si(n) (n = 1-7).

Binary C(7)Si(n) (n = 1-7) clusters are studied using density functional calculations at the level of B3LYP/6-311G(d). Lowest-energy structures have been determined theoretically and their properties such as binding energies, second differences in energy and highest-occupied and lowest-unoccupied molecular orbital gaps have been analyzed. It is found that the lowest-energy structures of the C(7)Si(n) (n = 1-7) clusters change from linear to planar when n ≥ 3, and in the planar structures C atoms prefer to form five- and six-membered rings surrounded by extra Si atoms in the form of the C(2)Si units.

Antifungal evaluation of cholic acid and its derivatives on Candida albicans by microcalorimetry and chemometrics.

In the last few years, several fungus infections caused by multidrug-resistant pathogenic agents have got tremendous emergence and prevalence. Screening for novel antifungal agents is in great demand, but traditional microbiological techniques are far from sufficient to meet that requirement. In this study, a non-invasive and non-destructive microcalorimetric method was performed to investigate the antifungal activities of cholic acid (CA) and its derivatives, glycocholic acid (GCA) and taurocholic acid (TCA) on the multiplying and non-multiplying metabolism of Candida albicans.

Automated synthesis of a 184-member library of thiadiazepan-1,1-dioxide-4-ones.

The construction of a 225-member (3 × 5 × 15) library of thiadiazepan-1,1-dioxide-4-ones was performed on a Chemspeed Accelerator (SLT-100) automated parallel synthesis platform, culminating in the successful preparation of 184/225 sultams. Three sultam core scaffolds were prepared based upon the utilization of an aza-Michael reaction on a multifunctional vinyl sulfonamide linchpin. The library exploits peripheral diversity in the form of a sequential, two-step [3 + 2] Huisgen cycloaddition/Pd-catalyzed Suzuki-Miyaura coupling sequence.

Solid-phase extraction and ultra high-performance liquid chromatography tandem mass spectrometry analysis of the gastrointestinal absorption of emodin in different digestive segments of rats.

A rapid, simple and sensitive ultra high-performance liquid chromatography (UHPLC-MS/MS) method was established for determining the absorption amount of emodin in the five digestive segments of rat. Plasma samples were pre-purified by solid-phase extraction (SPE) with Oasis MAX cartridge. Separation of emodin and 1,8-dihydroxyanthraquinone (internal standard) was performed on an Acquity BEH UHPLC C(18) column (100 mm × 2.

Combining (1)H NMR spectroscopy and chemometrics to identify heparin samples that may possess dermatan sulfate (DS) impurities or oversulfated chondroitin sulfate (OSCS) contaminants.

Heparin is a naturally produced, heterogeneous compound consisting of variably sulfated and acetylated repeating disaccharide units. The structural complexity of heparin complicates efforts to assess the purity of the compound, especially when differentiating between similar glycosaminoglycans. Recently, heparin sodium contaminated with oversulfated chondroitin sulfate A (OSCS) has been associated with a rapid and acute onset of an anaphylactic reaction.

Class modeling analysis of heparin 1H NMR spectral data using the soft independent modeling of class analogy and unequal class modeling techniques.

To differentiate heparin samples with varying amounts of dermatan sulfate (DS) impurities and oversulfated chondroitin sulfate (OSCS) contaminants, proton NMR spectral data for heparin sodium active pharmaceutical ingredient samples from different manufacturers were analyzed using multivariate chemometric techniques. A total of 168 samples were divided into three groups: (a) Heparin, [DS] ≤ 1.0% and [OSCS] = 0%; (b) DS, [DS] > 1.

Determination of galactosamine impurities in heparin samples by multivariate regression analysis of their (1)H NMR spectra.

Heparin, a widely used anticoagulant primarily extracted from animal sources, contains varying amounts of galactosamine impurities. Currently, the United States Pharmacopeia (USP) monograph for heparin purity specifies that the weight percent of galactosamine (%Gal) may not exceed 1%. In the present study, multivariate regression (MVR) analysis of (1)H NMR spectral data obtained from heparin samples was employed to build quantitative models for the prediction of %Gal.

Screening for novel antibacterial agents based on the activities of compounds on metabolism of Escherichia coli: a microcalorimetric study.

The emergence and prevalence of resistance to antibacterial agents is a pressing threaten for human health. Screening for novel antibacterial agents targeting not only multiplying but also non-multiplying bacteria using appropriate approach is in great demand. In this study, the microcalorimetric method was used to measure the metabolic curves of E.

Isolation and characterization of a gene encoding a polyethylene glycol-induced cysteine protease in common wheat.

Plant cysteine protease (CP) genes are induced by abiotic stresses such as drought, yet their functions remain largely unknown. We isolated the full-length cDNA encoding a Triticum aestivum CP gene, designated TaCP, from wheat by the rapid amplification of cDNA ends (RACE) method. Sequence analysis revealed that TaCP contains an open reading frame encoding a protein of 362 amino acids, which is 96% identical to barley cysteine protease HvSF42.

Geometric structures of Ge(n) (n=34-39) clusters.

The structures of Ge(n) (n=34-39) clusters were searched by a genetic algorithm using a tight-binding interatomic potential. First-principles calculations based on density functional theory were performed to further identify the lowest-energy structures. The calculated results show that Ge(n) (n=34-39) clusters favor prolate or Y-shaped three-arm structures consisting of two or three small stable clusters (Ge(6), Ge(7), Ge(9), or Ge(10)) linked by a Ge(6) or Ge(9) bulk unit.

Burn serum causes a CD14-dependent mitochondrial damage in primary cardiomyocytes.

Studies from animal models suggest that myocardial mitochondrial damage contributes to cardiac dysfunction after burn injury. In this report, we used an ex vivo model of primary cardiomyocyte culture to investigate the mechanisms of burn-induced mitochondrial impairment. Briefly, blood serum was collected from Sprague-Dawley (SD) rats subjected to 40% total body surface area burn and added (10% vol/vol) to primary cardiomyocytes prepared from SD rats.

[Clinical application of continuous douche and vacuum sealing drainage in refractory tissue, bone and joint infections after debridement].

Objective: To explore effect and the application value of continuous douche and vacuum sealing drainage (VSD) in refractory tissue, and joint infections after complete debridement.

Methods: As retrospective analysis of treatment time and restoration or recurrence, from Jan. 2006 to Dec.

Stabilities and fragmentation energies of Si(n) clusters (n = 2-33).

The structures of Si(n) (n = 2-33) were confirmed by genetic algorithm (GA)/tight binding (TB) search and ab initio calculations at the B3LYP/6- 311++G(2d) and PW91/6-311++G(2d) level, respectively. The fragmentation energies, binding energies, second differences in energy, and highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gaps in the size range 2≤n≤33 were calculated and analyzed systematically. We extended the cluster size involved in the fragmentation analyses up to Si(33), and studied the multi-step fragmentations of Si(n).

Platelike structures of semiconductor clusters Ge(n) (n = 40-44).

The structures of Ge(n) (n=40-44) clusters were searched by genetic algorithm combined with a tight-binding method. First-principles calculations based on density functional theory were performed to further optimize the isomer structures. The calculated results show that Ge(n) (n=40-44) clusters favor platelike structures, consisted of four small magic clusters (Ge(9) or Ge(10)), and a Ge(4) core.

Structures and stabilities of Pb(n) (n

We have performed global structural optimizations for neutral lead clusters Pb(n) (n = 2-20) by using a genetic algorithm (GA) coupled with a tight-binding (TB) potential. The low-energy structures identified from a GA/TB search were further optimized at the DFT-PBE level. The calculated results show that the Pb(n) (14 < n View Article and Find Full Text PDF

Bulklike structures for medium-sized Al(n) (n=31-40) clusters.

Neutral aluminum clusters Al(n) (n=31-40) were studied using a genetic algorithm (GA)/tight-binding (TB) search combined with DFT-PBE calculations. It is found that the medium-sized aluminum clusters Al(31) to Al(40) exhibit a bulklike stacking pattern. Anion clusters were also studied.

[Isolation, culture and purification of olfactory ensheathing cells from human fetal olfactory mucosa].

Objective: To explore the method for obtaining olfactory ensheathing cells from human fetal olfactory mucosa by cell culture for selective adhesion in the presence of neurotrophin-3 (NT3) and low-concentration serum.

Methods: The olfactory ensheathing cells were cultured alternatively in DMEM/F12 culture medium containing 10% fetal bovine serum (FBS) and the medium containing NT3 and 2.5% FBS every 72 h.

[Effect of xinkeshu tablet on heart rate variability in patients with coronary heart disease].

Objective: To evaluate the effect of Xinkeshu Tablet (XKS) on heart rate variability (HRV) in patients with coronary heart disease (CHD).

Methods: Sixty patients with their diagnosis of CHD confirmed by coronary angiography were randomized into two groups equally. Besides the conventional treatment for CHD, XKS and Metoprolol were given respectively to patients in the treated group and the control group for 8 weeks.

Raman calibration of the HT-7 yttrium aluminum garnet Thomson scattering for electron density measurements.

A multipulse neodym doped yttrium aluminum garnet laser Thomson scattering system calibrated by the anti-Stokes rotational Raman scattering from nitrogen gas had been developed in the HT-7 superconducting Tokmak. By virtue of this system, measured electron density results of the plasma were obtained. The results showed good repeatability and its total uncertainty was estimated to be +/-18%.

[Effects of blood-cooling and promoting drugs on rats with radiation-induced lung injury].

Objective: To investigate the effect of blood-cooling and promoting drugs (BCPD) on the dy-namic changes of collagens and the expressions of interleukin-6 (IL-6) and transforming growth factor beta (TGF-beta) in lung tissue of rats with radiation-induced lung injury (RILI) to explore the effects and action mech-anism of BCPD in preventing and treating RILI.

Methods: One hundred and sixty Wistar female rats were ran-domly divided into the radiation group, the treatment group, the blank control group and the drug control group. The rats in the first two groups received right hemithoracic fractionated radiation, and those in the treatment group were given BCPD.

Ultrasound and microbubbles: their functions in gene transfer in vitro.

To examine the role of ultrasound in gene delivery in vitro, three cells lines were exposed to the low-frequency ultrasound of varying intensities and for different durations to evaluate their effect on gene transfection and cell viability of the cells. Microbubble (MB), Optison (10%), was also used to observe the role of the microbubbles in gene transfection. The results demonstrated that as the ultrasound intensity and the exposure time increased, the gene transfer rate increased and the cell viability decreased, but at high energy intensities, the cell viability decreased dramatically, which caused the transfer rate to decrease.

Cardiac mitochondrial damage and inflammation responses in sepsis.

Background And Purpose: Studies in sepsis suggest that mitochondria mediate multiple organ dysfunction, including cardiac failure; however, the underlying molecular mechanisms remain elusive. This study examined changes in mitochondrial membrane integrity, antioxidant activities, and oxidative stress in the heart after infectious challenge (intratracheal Streptococcus pneumoniae, 4 x 10(6) colony-forming units). Inflammation responses also were examined.