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Betulinic acid has attracted attention in terms of its important biological and pharmacological characteristics. The main objective of this work was to optimize the variables of biotransformation process in order to enhance betulinic acid production from betulin catalysed by fungus Armillaria luteo-virens Sacc ZJUQH100-6.Fractional factorial design and response surface methodology were applied to optimize the main parameters that affect betulinic acid production in the growing-cells system. Results indicated that the addition of Tween 80 and substrate concentration were identified as the significant factors on betulinic acid formation, and the central composite experimental design was then adopted to derive a statistical model for optimizing biotransformation conditions. The optimum conditions were observed at pH 6·0, 0·57% Tween 80, 15 mg l(-1) betulin and at 3 days of stage of inoculation.Under the optimized conditions, the highest productivity of betulinic acid predicted was 9·32%, which increased by 74·53% in comparison with that of the nonoptimized. The verified experiment revealed that the model can well simulate betulin biotransformation. Moreover, the bioconversion of betulin and betulin-28-monooxygenase activities was compared between the optimized and the nonoptimized conditions.Current data imply that betulinic acid production from betulin can be effectively enhanced through biotransformation optimization strategy.

A prototype front end for undulator beamlines to be installed on the storage ring Elettra is presented. Design criteria are briefly discussed, in particular for those components which have to withstand heavy heat load.

Ectopic pituitary adenomas (EPAs) are rare lesions. The purpose of this study was to describe the CT and MRI features of sphenoid sinus EPAs. Eight patients with histology-proven EPAs in the sphenoid sinus, all of whom underwent CT and MRI, were reviewed retrospectively. The following imaging features were analysed: (i) size, (ii) margin, (iii) CT attenuation characteristics and (iv) MRI signal intensity. In addition, the involvement of adjacent structures and the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI were analysed. All EPAs had well-defined margins and showed no relationship to the intrasellar pituitary gland. The mean size was 28 mm (range, 20-46 mm). On non-enhanced CT, the lesions appeared isodense to grey matter in 7 (88%) patients and hypodense in 1 (12%) patient. Only two patients underwent post-contrast CT, and they showed moderate enhancement. On T1 weighted images, EPAs appeared isointense in 6 (75%) patients and hypointense in 2 (25%). On T2 weighted images, the lesions appeared hyperintense in 2 (25%) patients and isointense in 6 (75%). EPAs showed mild to moderate heterogeneous contrast enhancement and exhibited a cribriform-like appearance. Two patients underwent DCE MRI; the TIC showed a rapidly enhancing and slow washout pattern. The following features were also seen: an empty sella, bone changes and involvement of the cavernous sinus (5 patients; 62.5%). In conclusion, a high index of suspicion for EPA and a familiarity with the imaging findings may help to diagnose this rare entity accurately.

The vortex-lattice melting transitions in two typical iron-based high-Tc superconductor $Ba(Fe_{1-x}Co_{x})_{2}As_{2}$ (122-type) and$Nd(O_{1-x}F_{x})FeAs$ (1111-type) for magnetic fields both parallel and perpendicular to the anisotropy axis are studied within the elastic theory. Using the parameters from experiments, the vortex-lattice melting lines in the H-T diagram are located systematically by various groups of Lindemann numbers. It is observed that the theoretical result for the vortex melting on $Ba(Fe_{1-x}Co_{x})_{2}As_{2}$ for parallel fields agrees well the recent experimental data. The future experimental results for the vortex melting can be compared with the present theoretical prediction by tuning reasonable Lindemann numbers., Comment: 10 pages, 5 figures

The Super‐ESCA beamline has been designed for high resolution core level spectroscopy of adsorbates on single crystal surfaces using soft x‐ray synchrotron radiation. It receives the light from an 81 period undulator with 5.6 cm period and 4.5 m length in the storage ring ELETTRA. The tunability of this insertion device, at a storage ring electron energy of 2.0 GeV and the connected modified SX700 monochromator allows the performance of experiments at this beamline in the photon energy range 100–2000 eV. This beamline is now operational and first absorption spectra are presented which show available resolving powers varying from 8000 to 3000 for photon energies between 240 and 850 eV.

In this review, we will focus on the central neural mechanisms that couple osmotic perturbations to changes in sympathetic nerve discharge, and the possible impact these actions have in cardiovascular diseases such as arterial hypertension and congestive heart failure.Changes in extracellular fluid osmolality lead to specific regulatory responses in defence of body fluid and cardiovascular homeostasis. Systemic hyperosmolality is well known to stimulate thirst and the release of antidiuretic hormone. These responses are largely due to osmosensing neurones in the forebrain lamina terminalis and hypothalamus and are critical elements in a control system that operates to restore body fluid osmolality. An equally important, but less characterized, target of central osmoregulatory processes is the sympathetic nervous system.Understanding the neurobiology of sympathetic responses to changes in osmolality has important implications for body fluid and cardiovascular physiology. By stabilizing osmolality, vascular volume is preserved and thereby relatively normal levels of cardiac output and arterial pressure are maintained.

Using the molecular dynamic method we investigate numerically the current driven vortex motion in a superconducting film with periodic arrays of both ferromagnetic (FM) and anti-parallel ferromagnetic (AFM) dots. The simulation results show that in the absence of thermal fluctuation the vortex motion is dominated by the configurations of the magnetic dot array. This guided vortex motion is only observed at the onset of the depinning of the interstitial vortices. Two guided vortex motion mechanisms are discussed in this work. For the AFM configuration the vortex motion is mainly originated by the existence of magnetic dots with opposite magnetized moments, while for the FM case it is mainly dependent on the degree of the condensed packing of the magnetic dot lattice constant.

In the usual formulation of the equations for competitive binding assays, the free concentrations of the various unlabeled ligands are approximated by the known values of their total concentrations, since the free concentrations are not easily determined. Although equations have been derived previously that give the exact solution with the free concentrations of unlabeled ligands treated as variables, these have not been useful in practice. We have devised a mathematical model for the competitive binding that which is both exact and practical for the general case of one labeled ligand, any number of unlabeled ligands, and any number of classes of binding sites. In this model, the total concentrations of unlabeled ligands are the explicit variables, instead of their free concentrations. The free concentrations of unlabeled ligands can be estimated from the model. The model is based on the law of mass action and the dilution principle, as well as a new concept, called the equivalent competitive binding principle.

Hypoxic and exercises ventilatory responses measured in Tibetan who lived at moderate (2000-3000m, M-Tibetan) and high (4000-4700m, H-Tibetan) altitude areas. The result showed that the slope of hypoxic ventilatory response (HVR; VE/SaO2) in M- and H-Tibetan was 0.81 +/- 0.07 and 0.46 +/- 0.04 L/min/%SaO2 (P0.01) and the maximal exercise ventilation (VEmax) was 78.3 +/- 3.5 and 68.2 +/- 2.1 L/min (P0.05), respectively. There were positive correlation between delta VE/delta SaO2 and VEmax, which gamma = 47.0 +/- 37.3x, r = 0.70 in M-Tibetan, and gamma = 53.8 +/- 31.4x, r = 0.67 in H-Tibetan. Maximal heart rate of the H-Tibetan was significantly lower than that in the M-Tibetan (P0.01). It is suggested that the attenuation of HVR depends on the magnitude of the hypoxic stimulus. Therefore, there are differences even among the high-altitude natives in ventilatory response to hypoxia, e.g. normal respiratory sensitivity to hypoxia in moderate-altitude natives, and blunted in high-altitude natives.

The therapeutic effects of intentional hemodilution (IHD) on 64 patients of rheumatic mitral valvular disease with chronic pulmonary stasis were estimated. The mean hematocrit was decreased from 0.50 +/- 0.06 to 0.41 +/- 0.04 by withdrawing blood and replacing it with diluent. The whole blood ratio viscosity was decreased from 11.7 +/- 2.4 to 6.4 +/- 0.8 (P0.01), the pulmonary arterial pressure was reduced from 6.4 +/- 0.6 to 4.1 +/- 0.5 kPa (0.133 kPa = 1 mmHg) (P0.01), the pulmonary vascular resistance brought down from 536.0 +/- 108.0 to 315.0 +/- 62.0 dynes.s.cm-5 (P0.01), the cardiac output increased from 3.4 +/- 0.4 to 5.6 +/- 0.5 L/min (P0.01), the cardiac index increased from 2.2 +/- 0.5 to 3.5 +/- 0.4 L/min/m2 (P0.01), and venous oxygen saturation and oxygen content increased from 28.5 +/- 3.4%, 5.1 +/- 0.5% to 56.0 +/- 5.0%, 11.3 +/- 1.2%, respectively (P0.01). The patients' symptoms and signs improved significantly. The protective role of IHD in the early stage of lethal pulmonary edema induced by epinephrine in 39 rabbits and 27 rats was also observed. The experimental data show that intentional hemodilution increased the animals' survival rate (P0.01), reduced the pulmonary coefficient, permeability index of Evans blue and protein content in broncho-alveolar lavage fluid (BALF) (all P0.01), and alleviated the pathomorphological changes of the lungs of animals in Group IHD were alleviated. The results suggest that IHD acts well in both chronic pulmonary stasis and acute pulmonary edema.

In phosphate buffer (pH 7.40), at 20.00 +/- 0.05 degrees C, the visible spectra of Cu(II) and Cu(II) complexes and the kinetics of ascorbic acid oxidation catalyzed by Cu(II)/H2DCA in the presence of DNA were studied. Measurements were reported on rate of .OH formation by the oxidation of ascorbic acid in the presence of Cu(II)/H2DCA. It showed that ternary complex Cu(II)/H2DCA/DNA may exist in the system in which DNA strand was broken by ascorbic acid in the presence of Cu(II)/H2DCA, and it was assumed that the DNA-breaking action of ascorbic acid in the presence of Cu(II)/H2DCA conformed to site-specific Fenton reaction mechanism. All the result of DNA-breaking action can be explained in terms of this site-specific Fenton reaction mechanism.

About thirty thousands horses were affected and hundreds of them died in an epidemic caused by equine 2 influenza virus (H3N8) in China. The estimated morbidity and mortality accounted for 81% and 2%, respectively. The viral protein and RNA electrophoresis patterns revealed that the new isolates were antigenically different from the prototype strain influenza A/eq/Miami/1/63(H3N8). Therefore, the representative strain of the equine 2 subtype of influenza A virus recommended for producing reference reagents, vaccines, and for serological diagnosis must have been altered by antigenic drift.

This paper reports the variation of peripheral T lymphocyte subsets in patients before and after operation under epidural anesthesia using OKT monoclonal antibodies (McAb). The results show that TH and TS after anesthesia and during surgery were lower than before anesthesia and in normal controls (P less than 0.05). The ratio of TH/TS after anesthesia and during operation were lower than before anesthesia (P less than 0.05), but there was no significant difference with normal controls (P greater than 0.05). Therefore, we consider that the decrease in TH cells was one of the reasons for decrease in patient immune function during anesthesia and surgery. Five to seven days after surgery, patient TH cell levels tended to normalize. This showed that this abnormality was transient and reversible. The results also indicated that emphasising prevention of infection in post-operational case, should be done during the first 5-7 days after surgery.

Preparation of methotrexate microsphere (MTX-ms) by emulsion-freezing technique was introduced and the experimental results proved that MTX entrapped in the microspheres exhibited good stabilities towards temperature, cobalt-60 radiation and light. The dissolution and inflation rate of the microspheres in pH 7.4 buffer solution at different times measured by Coulter counter was presented. Antitumor activity of MTX-ms after hepatic arterial embolization was examined in a model of liver tumor in Wistar rats. The group of rats treated with MTX-ms showed a rather significant reduction in tumor growth and more extended tumor necrosis as compared with the other groups, e.g. normal saline solution, MTX solution, placebo gelatin-ms and the results demonstrate that the effect of arterial chemoembolization used by MTX-ms is superior to that of the groups either using arterial chemotherapy or arterial embolization alone in treating rat liver cancer.

The cross-linked MTX-gelatin microsphere was chosen as an experimental model. Pharmacokinetics and biodegradable period of the microsphere were studied after hepatic arterial embolization in vivo in dogs. After hepatic arterial infusion, the concentration of MTX-ms in peripheral vein blood increased rapidly and declined slowly. In contrast, the peak time of the drug concentration of infused MTX solution appeared at once and decreased rapidly. The half-life of MTX-ms in vivo was 2.14 times as much as that of MTX solution. During the assay period of sixteen hours the drug concentration of MTX-ms in hepatic vein blood was constantly higher than that of MTX solution. The follow-up angiography revealed that microsphere is a kind of peripheral embolic agent and its degradable time in vivo is about one month. Both sustained release and embolization effectiveness of microsphere will be significant in treatment of hepatic cancer.

In the presence of Mg2+, the pig erythrocyte membranes were incubated with [gamma-32P]ATP at 30 degrees C for 3 min to study the effects of some chemicals on the phosphorylation of phosphatidylinositol. The incubations were stopped by the addition of chloroform/methanol (2:1, vol/vol) and the phospholipids were extracted with acid chloroform/methanol and separated on silica gel TLC plates. [gamma-32P] phosphatidyl-inositol-4-phosphate was quantitated by scintillation counting and autoradiography. The results indicated that heparin and neomycin inhibited the phosphorylation of phosphatidylinositol in a concentration-dependent manner, while dimethylsulfoxide stimulated the phosphorylation at low concentration (less than 10%), but inhibited at high concentration (greater than 10%). Hexachlorocyclohexane stimulated the phosphorylation within a certain limit of concentration up to 6.4 micrograms/ml. Li2SO4 (10 mmol/L), EGTA (100 mumol/L) and theophylline (100 mumol/L) had no significant effects.