Search

Modulation of Pd nanoparticle (NP) crystallinity is achieved by switching the surfactants of different binding strengths. Pd NPs synthesized in the presence of weak binding surfactants such as oleylamine possess polyhedral shapes and a polycrystalline nature. When oleylamine is substituted by trioctylphosphine, a much stronger binding surfactant, the particles become spherical and their crystallinity decreases significantly. Moreover, the Pd NPs reconvert their polycrystalline structure when the surfactant is switched back to oleylamine. Through control experiments and molecular dynamics simulation, we propose that this unusual nanocrystallinity transition induced by surfactant exchange was resulted from a counterbalance between the surfactant binding energy and the nanocrystal adhesive energy. The findings represent a novel postsynthetic approach to tailoring the structure and corresponding functional performance of nanomaterials.

A new nortriterpenoid saponin, 3β,17β-dihydroxy-28-nor-12-oleanen-16-one 3-O-β-d-galactopyranosyl (1 → 2)-{α-l-arabinopyranosyl (1 → 3)-[α-l-arabinofuranosyl (1 → 4)-β-d-glucuronopyranoside]} (1), along with two pairs of known isomers, was isolated from the roots of Symplocos caudata Wall. Their structures were elucidated by spectroscopic and chemical methods.

Homogeneous and stable magnetic nanofluids containing γ-Fe2O3 nanoparticles were prepared using a two-step method, and their thermal transport properties were investigated. Thermal conductivities of the nanofluids were measured to be higher than that of base fluid, and the enhanced values increase with the volume fraction of the nanoparticles. Viscosity measurements showed that the nanofluids demonstrated Newtonian behavior and the viscosity of the nanofluids depended strongly on the tested temperatures and the nanoparticles loadings. Convective heat transfer coefficients tested in a laminar flow showed that the coefficients increased with the augment of Reynolds number and the volume fraction.

Two new quinochalcone compounds, named saffloquinoside A (1) and saffloquinoside B (2), were isolated from the florets of Carthamus tinctorius. Their unusual structures including their absolute stereochemistry were elucidated based on UV, IR, HRESIMS, 1D and 2D NMR data, and CD spectrum. Saffloquinoside A has an uncommon six-five member dioxaspirocycle and saffloquinoside B has a cyclohexatrione skeleton with a benzyl group and two C-glycosyl units. Saffloquinoside A exhibited middling anti-inflammatory activity.

A new morphology of Prussian blue microcrystals has been prepared by selective etching. By thermal decomposition, PB has been transformed into mesoporous magnetic iron(III) oxide.

Background: Mechanical ventilation with a high tidal volume (VT) increases lung and systemic plasminogen activator inhibitor (PAI)-1 levels and alveolar fibrin deposition. Activated protein C (APC) may decrease PAI activity in endothelial cell-conditioned medium and thus enhance fibrinolysis., Objectives: The aims of this study were to test the hypothesis that APC can neutralize PAI-1 activity and improve lung function in an animal model of ventilator-induced lung injury., Methods: Rats were ventilated with a high-volume zero positive end-expiratory pressure (PEEP; HVZP) protocol by a volume-cycled ventilator for 2 h at a VT of 30 ml/kg, a respiratory rate of 25 breaths/min, and an FiO(2) of 0.21. Fifteen minutes before ventilation, the rats received intravenous APC (250 microg/kg, HVZP+APC group) or normal saline (vehicle; HVZP group). Another group that received no ventilation served as the control group., Results: Levels of arterial blood gas tension were comparable between the two ventilation groups throughout the study period. Rats treated with the HVZP protocol exhibited significantly higher total protein and macrophage inflammatory protein-2 concentrations in bronchoalveolar lavage fluid (BALF) and higher lung PAI-1 mRNA expression and plasma active PAI-1 levels than did the control group. Administration of APC tended to reduce the BALF protein content and systemic PAI-1 activity but did not improve the lung histology in the HVZP+APC group. Plasma levels of D-dimers were comparable among the three study groups., Conclusions: These results suggest that APC administered at a higher dosage might improve lung function by reducing alveolar protein leakage and systemic coagulation., (Copyright (c) 2010 S. Karger AG, Basel.)

Much interest has been attracted to the magnetic materials with porous structure because of their unique properties and potential applications. In this report, Fe3O4nanoporous particles assembled from small Fe3O4nanoparticles have been prepared by thermal decomposition of iron acetylacetonate in the presence of polyethylene glycol 4000. The size of the spherical nanoporous particles is 100-200 nm. Surface area measurement shows that these Fe3O4nanoporous particles have a high surface area of 87.5 m2/g. Magnetization measurement and Mössbauer spectrum indicate that these particles are nearly superparamagnetic at room temperature. It is found that the morphology of the products is greatly influenced by polyethylene glycol concentration and the polymerization degree of polyethylene glycol. Polyethylene glycol molecules are believed to facilitate the formation of the spherical assembly.

By loading doxorubicin (DOX) on 5-carboxyl-fluorescein (FAM) labeled AGKGTPSLETTP peptide (A54) coupled starch-coated iron oxide nanoparticles (SIONs), we prepared a novel aqueous drug delivery system with both magnetic and biomolecular targeting, which was specific to human hepatocellular carcinoma cell line BEL-7402. The saturated extent of adsorption reached 2.0 mg DOX/mg A54-SIONs at 28 degrees C, which provided a rather high dose of DOX loading for application. Tests in vitro demonstrated the specificity of DOX-loaded A54-SIONs to BEL-7402 cells. The microscopy images proved that DOX-loaded A54-SIONs were successfully targeted to tumor tissue of nude mice with an external magnetic field in vivo. MTT assay showed higher cytostatic effect of DOX-loaded A54-SIONs to hepatocellular carcinoma cells BEL-7402 than that of DOX-loaded SIONs.

Objective: To study the chemical constituents from the flowers of Carthamus tinctorius., Method: Compounds were isolated by chromatographic techniques. Their structures were elucidated by spectral methods., Result: Ten compounds were identified as 7,8-dimethylpyrazino [2,3-g] quinazolin-2, 4-(1H, 3H) -dione (1), adenosine (2), adenine (3), uridine (4), thymine (5), uracil (6), roseoside (7), 4'-O-dihydrophaseic acid-beta-D-glucopyranoside methylester (8), 4-O-beta-D-glucopyranosyloxy-benzoic acid (9) and p-hydroxybenzoic acid (10)., Conclusion: Compounds 1 and 8 were isolated from natural plants for the first time, and compounds 7, 9 and 10 were isolated from this plant for the first time.

Four novel anthraquinone-benzisochromanquinone dimers, named floribundiquinones A, B, C, and D (1-4), along with six known anthraquinones, 10-(chrysophanol-7'-yl)-10-hydroxychrysophanol-9-anthrane (5), physcion (6), chrysophanol (7), 1,5,8-trihydroxy-3-methyl-anthraquinone (8), aloe-emodin (9), and xanthorin (10), were isolated from the roots of Berchemia floribunda. Their structures including the absolute axial stereochemistry were elucidated on the basis of spectroscopic methods. Floribundiquinones represent a novel carbon skeleton with an anthraquinone-benzisochromanquinone unit. Hepatoprotective activities were evaluated against D-galactosamine-induced toxicity in WB-F344 rat hepatic epithelial stem-like cells.

Two new spermidine compounds, namely safflospermidine A (1) and safflospermidine B (2), together with two known compounds, N(1),N(5),N(10)-(Z)-tri-p-coumaroylspermidine (3) and N(1),N(5),N(10)-(E)-tri-p-coumaroylspermidine (4), were isolated from the florets of Carthamus tinctorius L. Their structures were elucidated by spectroscopic means.

As a homing peptide, A54 is the most effective peptide specific to the human hepatocellular carcinoma cell. Homing peptide labeled with green fluorescent protein (A54-GFP) was successfully immobilized on the surfaces of magnetic nanoparticles and characterized by Fourier transform infrared spectroscopy as well as fluorescence microscopy. The binding efficiency was analyzed by performing adsorption equilibrium and SDS-PAGE electrophoresis. Specific binding of the nanoparticles functionalized with A54-GFP to human hepatocellular carcinoma cells in vitro was visualized using fluorescence microscopy. The results demonstrated the specificity of A54-GFP-coated magnetic nanoparticle to tumor cell, pointing to its great potential in magnetic cell separation and purification, magnetic resonance imaging (MRI), magnetic hyperthermia, and drug targeting., ((c) 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008.)

We investigated the suppressive effects of 3-O-methylquercetin 5,7,3',4'- O-tetraacetate (QMTA), a more-potent phosphodiesterase (PDE)3/4 inhibitor than quercetin 3-O-methyl ether (3-MQ), which has been reported to have the potential for treating asthma, against ovalbumin (OVA)-induced airway hyperresponsiveness (AHR). The IC50 value of QMTA for PDE3 was significantly less than that for PDE4. According to the Lineweaver-Burk analysis, QMTA (1-10 microM) competitively inhibited PDE3 and PDE4 activities. The Ki values were 0.9+/-0.3 (n=5) and 3.9+/-0.5 (n=5) microM, respectively, which significantly differed from each other, suggesting that QMTA has higher affinity for PDE3 than for PDE4. QMTA (3-10 microM) concentration-dependently relaxed the baseline level, and significantly inhibited cumulative OVA (10-100 microg/mL)-induced contractions in isolated sensitized guinea pig trachealis suggesting that QMTA has bronchodilator and inhibiting effects on mast cell degranulation. After the secondary challenge, the AHR was measured in unrestrained OVA-sensitized mice, with nebulized methacholine (MCh, 6.25-50 mg/mL), by barometric plethysmography using a whole-body plethysmograph. In the present results, QMTA (3-10 micromol/kg, I. P.) dose-dependently attenuated the enhanced pause (Penh) value induced by MCh (25-50 mg/mL). QMTA (3-10 micromol/kg, I. P.) also significantly inhibited total inflammatory cells, macrophages, neutrophils, lymphocytes, and eosinophils in BALF after determination of Penh values. It also significantly suppressed the release of interleukin (IL)-2, IL-4, IL-5, IFN-gamma, and TNF-alpha, with the exception that 3 micromol/kg QMTA did not suppress the releases of IL-5. QMTA even at 1 micromol/kg significantly inhibited eosinophils, IL-2, and TNF-alpha. In conclusion, our results strongly suggest that QMTA has greater potential than 3-MQ for the treatment of asthma.

Two new benzochromone glycosides, rubrofusarin 6-O-alpha-L-rhamnosyl- (1 --> 6)-O-beta-D-glucopyranoside (1) and demethylflavasperone 10-O-beta-D-glucopyranoside (2), have been isolated from the stem of Berchemia racemosa Sieb. et Zucc. (Rhamnaceae). Their structures were elucidated on the basis of spectroscopic evidence.

We hypothesized that lung inflammation and parenchymal apoptosis in ventilator-induced lung injury (VILI) are related to ANG II and assessed the ability of the angiotensin-converting enzyme inhibitor captopril to attenuate VILI in rats. Adult male Sprague-Dawley rats were randomized to receive two ventilation strategies for 2 h: 1) tidal volume of 40 ml/kg, respiratory rate of 25 breaths/min, and inspiratory O2 fraction of 0.21 [high-volume, 0 positive end-expiratory pressure (HVZP) group] and 2) injection of captopril (100 mg/kg ip) 30 min before HVZP ventilation (HVZP+CAP group). Another group, which did not receive ventilation, served as the control. Mean arterial pressure was significantly lower in the HVZP+CAP group than in the HVZP group at 2 h of ventilation. Total protein levels were significantly higher in bronchoalveolar lavage fluid (BALF) recovered from HVZP-ventilated rats than from controls. BALF macrophage inflammatory protein-2 and lung ANG II were significantly higher in the HVZP group than in the control and HVZP+CAP groups. Lung ANG II levels correlated positively with BALF protein and macrophage inflammatory protein-2. The number of apoptotic airway and alveolar wall cells was significantly higher in the HVZP and HVZP+CAP groups than in the control group and significantly lower in the HVZP+CAP group than in the HVZP group. These results suggest that the efficiency of captopril to attenuate VILI is related to reduction of inflammatory cytokines and inhibition of apoptosis and indicate that VILI is partly mediated by the local angiotensin system.

Objective: To study the chemical constituents from the roots of Cudrania cochinchinensis., Method: The chemical constituents of C. cochinchinensis were isolated and purified by silica gel, polyamide column chromatography, Their structures were identified on the basis of spectroscopic data., Result: Six compounds were isolated and identified. Their structures were established as 3, 5, 7, 4"-tetrahydroxyflavanone-7-O-(6"-acetyl)-glucoside (1), 3, 5, 7, 4'-tetra hydroxyflavanone-7-O-glucoside (2), 2', 4', 5, 7-tetrahydroxy-6-prenyldihydroflavanone (3), 5, 7, 4'-trihysdroxy-6-prenylisoflavanone (4), 1, 3, 5, 6-tetrahydroxyxanthone (5), stilbene-2, 4, 3', 5'-tetraol (6)., Conclusion: Compound 1 was isolated from this genus, while compounds 4 and 5 were isolated from this plant for the first time.

The development of rubber industry depends on the sustainable management of rubber plantation. To evaluate the environmental effects of planting Hevea brasiliensis on a subsystem of tropical forest ecosystem, the variation of soil fertility and carbon sequestration under rubber plantation within 30-year life period were investigated in Hainan Island. Results showed that (1) with the increase of stand age of rubber plantation, soil fertility decreased all along. From 1954 to 1995, soil organic matter, total N, available K and available P decreased by 48.2%, 54.1%, 56.7% and 64.1%, respectively. (2) If the complete return of litters was considered without additional fertilizer application to the soil of the rubber plantations, the consumption periods for P, N, K, Mg were only 825 years, 329 years, 94 years and 65 years, respectively. To improve soil fertility is essential for rubber plantation development. (3) The C sequestration of rubber trees per hectare accounts for 272.08 t within 30-year life period and 57.91% of them was fixed in litters. In comparison with C sequestration by rain forest (234.305 t/hm2) and by secondary rain forest (150.203 t/hm2), rubber forest has more potentials for C fixation. On the base of above results, the following measures would benefit the maintenance of soil fertility and the development of rubber industry, including applying fertilizer to maintain the balance of soil nutrients, intercropping leguminous plant to improve soil fertility, reducing the collection of litters, optimizing soil properties to improve element P availability such as applying CaCO3. The information gathered from the study can be used as baseline data for the sustainable management of rubber plantation elsewhere.

Background: Extraneural metastasis of oligodendroglioma is extremely rare and is diagnosed primarily by biopsy or autopsy and very occasionally by fine needle cytologic examination. We report a case of metastatic oligodendroglioma diagnosed by cytologic examination of a pleural effusion. Such a diagnosis has not been reported before., Case: A 64-year-old woman developed anemia and bilateral pleural effusion 7 years after an operation for an oligodendroglioma over the left frontal lobe. Cytologic examination of the pleural effusion showed aggregates of atypical polygonal cells containing round, hyperchromatic nuclei and scanty, granular cytoplasm in Liu's and Papanicolaou stain and cell blocks. Immunohistochemical staining of the tumor cells revealed a positive reaction for antibodies to glial fibrillary acidic protein, S-100 and Olig2. Pleural biopsy confirmed the cytologic diagnosis of pleural effusion. A pathologic fracture of the right humeral and femoral bones was noted 1 month later, and the specimen also showed infiltrating oligodendroglioma cells in bone tissue., Conclusion: To the best of our knowledge, this is the first metastatic oligodendroglioma diagnosed by pleural cytology. Fine needle cytology can provide a reliable and rapid way to detect an extracranial metastatic oligodendroglioma in different organs.

Objective: To investigate the constituents of Ervatamia hainanensis systematically., Method: Various chromatographic techniques were applied to isolate and purify the constituents of this plant. The structures were elucidated by spectroscopic analysis., Result: Eight compounds were obtained, which were identified as alpha-amyrin acetate (1), 11-oxo-alpha-amyrin acetate (2), beta-sitosterol (3), cycloart-23-ene-3beta, 25-diol(4), cycloart-25-ene-3beta, 24-diol (5), 5alpha, 8alpha-epidioxyergosta-6, 22-dien-3beta-ol (6), ibogamin-3-one (7), beta-daucosterol (8)., Conclusion: Compounds 1, 2, 4- 7 were isolated from this plant for the first time.

Objective: To evaluate the feasibility and efficacy of intraperitoneal chemotherapy for malignant ascites caused by different types of abdominal cancers guided by chemo-sensitivity methyl tetrojolium coloremetric (MTT) assay in vitro., Methods: Cancer cells in the malignant ascites were collected for MTT assay to determine the chemo-sensitivity. The drug producing the highest or the second highest inhibition rate was selected for intraperitoneal chemotherapy. The correlation between the results of MTT assay and the response of malignant ascites, the clinical features, Karnofsky performance score (KPS) and prognosis were analyzed., Results: MTT assay indicated that Taxotere (TXT) and Hydroxycamptothecin (HCPT) were the most effective to cancer cells in malignant ascites, and HCPT was mostly frequently used for intraperitoneal chemotherapy (56.9%). Twenty-four patients showed response by intraperitoneal chemotherapy (complete response: 7; partial response: 17) with a slightly significant correlation between the results of MTT assay and response of malignant ascites (P = 0. 014). The KPS of the responders was improved significantly (P < 0.001), and the response of malignant ascites to intraperitoneal chemotherapy was demostrated as an independent prognostic factor by multi-variate analysis in this series., Conclusion: In vitro chemo-sensitivity MTT assay guided intraperitoneal chemotherapy for malignant ascites is simple, effective and safe, which can improve the KPS and prognosis of the responders.

Rhamnus nakaharai Hayata (Rhamnaceae) is used as a folk medicine in Taiwan for treating constipation, inflammation, tumors, and asthma. 3-O-Methylquercetin (3-MQ), a main constituent of the plant, has been reported to have potential for use in the treatment of asthma. The mechanisms of anti-inflammation of 3-MQ are still unclear. Nitric oxide (NO) production induced by lipopolysaccharide (LPS) through iNOS expression in RAW 264.7 cells, a mouse macrophage cell line, may reflect the degree of inflammation and may provide a measure for assessing the effect of drugs on the inflammatory process. Therefore, we were interested in investigating the mechanisms of suppression of NO production by 3-MQ in RAW 264.7 cells. 3-MQ (1-10 microM) concentration-dependently inhibited LPS (100 ng/mL)-induced NO production in RAW 264.7 cells. The IC(50) value was calculated to be 4.23 microM. 3-MQ (1-10 microM) significantly and concentration-dependently inhibited LPS (100 ng/mL)-induced iNOS protein and mRNA expressions in cells. The IC(50) values were calculated to be 4.36 and 6.53 microM, respectively. There was no significant difference among these three IC(50) values of 3-MQ. In conclusion, 3-MQ may exert its anti-inflammatory effect through the inhibition of iNOS DNA transcription.

Objective: To study the chemical constituents from root of Prismatomeris tetrandra., Method: Compounds were isolated by chromatographic techniques on silica gel column. Their structures were elucidated by chemical and spectral methods., Result: Six compounds were identified as 1-hydroxy-2-methylanthraquinone (I), 2-hydoxy-3-methoxyanthraquinone (II), 1, 3-dihydroxy-2-methoxyanthraquione (II), rubiadin (IV), rubiadin-1-methyl ether (V) and beta-sitosterol (V)., Conclusion: I, II and III were isolated from the plant for the first time.

Three new anthraquinones, 1-hydroxy-2,3-dimethoxy-7-methyl-9,10-anthraquinone, 1,3-dihydroxy-5,6-dimethoxy-2-methyl-9,10-anthraquinone, and 3-hydroxy-1,5,6-trimethoxy-2-methyl-9,10-anthraquinone, along with five known anthraquinones were isolated from the roots of Prismatomeris tetrandra. Their structures were determined on the basis of spectroscopic data.

The reaction product of cobalt carbonyl decomposition depends on the concentration of the oleic acid ligand. With a low concentration of ligand, nanocrystals nucleate and grow to large ferromagnetic particles through the process of Ostwald ripening and coalescence coarsening. With a high concentration of ligand, stable cluster complexes are formed. Addition or removal of ligand from the reaction products can interchange the formation of cluster complexes and nanocrystals.

In an attempt to construct a DNA vaccine against chicken coccidiosis, the TA4 gene of Eimeria tenella strain BJ was ligated to the mammalian expression vector pcDNA3.1/Zeo(+) to give pcDNA3.1-TA4 (pcDT). Then, Et1A (E. tenella refractile body gene) was ligated to it, upstream, aiming to be expressed in fusion with TA4, giving pcDNA3.1-Et1A-TA4 (pcDET). The constructed DNA vaccines were given to broilers intramuscularly 10-15 min after the breasts had been pre-treated with 25% sucrose solution. At 7 days after the second vaccination, chickens were challenged with 3 x 10(4) sporulated oocysts of E. tenella BJ. The chickens were killed and the lesion scores of the ceca, the relative body-weight gains and the numbers of oocysts in the ceca of each group of chickens were calculated at day 8 post-inoculation. Results indicated that both pcDT and pcDET could induce protective immunity against coccidial challenge. Their use could obviously reduce oocyst output and alleviate chicken body-weight decrease due to coccidial infection. An anti-coccidial index of 160 was achieved with a treatment of 50 microg pcDET and 100 microg pcDT.

Background: The incidence of carcinoma of the pancreas is increasing in the world. Pancreatic carcinoma is characterized by early local extension to contiguous structures and metastases to regional lymph nodes and the liver. This study was conducted to increase the rate of pancreatoduodenectomy combined with vascular reconstruction., Methods: Pancreatoduodenectomy with vascular reconstruction was performed for 79 patients at a number of hospitals in Fujian Province, Zhejiang Province, Shanghai and Xinjiang Uyghur Autonomous Region from April 1994 to December 2003. One of these patients also underwent right hemicolectomy; but all received through superior mesenteric vein (SMV)-portal vein (PV) reconstruction. The reconstructions of the superior mesenteric artery (SMA) and hepatic artery (HA) were performed in 4 patients, and reconstructions of the SMA or HA were carried out in 7 and 4 patients respectively. Partial reconstruction of the inferior vena cava (ICV) was done in 2 patients when the tumor was adhering to the wall of the inferior caval vein., Results: Four patients died during the peri-operative period, with a mortality rate of 5%. No complications such as biliary or pancreatic fistulae or artificial blood vessel infection were noted. Histological examination showed one patient with neuroendocrine cancer and the other 78 patients with adenocarcinoma of the pancreatic head. Resected endothelia and vascular margins proved to be microscopically tumor-free. Follow-up for 3 months to 10 years for all except two patients showed 7 of the 9 patients who had undergone resection and reconstruction of the SMA and HA died 7 months or 4 years after operation and 37 survived for over 3 years and 12 for more than 5 years. The rest are still under follow-up., Conclusion: Pancreatoduodenectomy with vascular reconstruction for carefully selected patients with carcinoma of the pancreatic head has proved to be a safe and reliable treatment, capable of raising the rates of tumor resection and survival.

We introduce nuclear resonant magnetometry as a means to record the magnetization curve of isotopically enhanced regions of a sample. It is based on nuclear resonant scattering with circularly polarized synchrotron radiation and the use of a nuclear resonant reference sample. We apply this approach to study the interlayer coupling in Fe/Cr(100) multilayers and to obtain a layer-specific magnetization curve. Our measurements provide experimental evidence for the existence of a nontrivial interlayer-coupling angle in Fe/Cr/Fe.

AqpZ is a 24 kDa integral membrane protein that facilitates water movement across the plasma membrane of Escherichia coli. In this study, the first crystallization and preliminary X-ray analysis of AqpZ are described. AqpZ was overexpressed and purified with a yield of 13 mg of purified AqpZ per litre of cell culture. The purified AqpZ was shown to be a monodisperse species consisting of tetrameric protein-detergent complexes. A crystallization condition for producing diffraction-quality crystals was identified. Initial X-ray analysis indicated that the diffraction limit of AqpZ extended to 3.6 A. Crystals were found to belong to space groups P4(1)22 or P4(3)22, with unit-cell parameters a = b = 119.04, c = 380.23 A.

Objectives: To describe the clinical characteristics and outcomes of patients with severe acute respiratory syndrome (SARS)., Methods: Between March 28 and June 30 '2003, 29 patients with probable SARS seen at Shin Kong Wu Ho-Su Memorial Hospital, Taipei, were analysed., Results: Presenting symptoms included fever (100%), cough (69.0%), chills or rigor (62.1%), and shortness of breath (41.4%). Mean days to defervescence were 6.8+/-2.9 days, but fever recurred in 15 patients (51.7%) at 10.9+/-3.4 days. Common laboratory features included lymphopenia (72.4%), thrombocytopenia (34.5%) and elevated C-reactive protein (CRP), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) (93.1, 62.1, 44.8%, respectively). All patients except one had initial abnormal chest radiographs and 20 (69.0%) had radiological worsening at 7.5+/-2.6 days. Nine patients (31.0%) subsequently required mechanical ventilation with four deaths (13.8%). Most patients with clinical deterioration responded to pulse corticosteroid therapy (14 out of 17) but six complicated with nosocomial infections. The risk factors associated with severe disease were presence of diarrhoea, high peak LDH and CRP, high AST and creatine kinase on admission and high peak values., Conclusions: Prudent corticosteroid use, vigilant microbiological surveillance and appropriate antibiotics coverage are the key to successful treatment.

The impacts of economic forest on global environmental change (GEC) are one of the hot issues in environmental study. Based on the 3-year observation data and 40-year climate data, GEC and analysis of the hydrological dynamic characteristics of rubber plantations and estimate of the water balance in the rubber plantations in Hainan Island were made. The results showed that the rainfall intercepted by the canopy of the plantations accounted for 11.45% of the annual rainfall, the total runoff for 23.71%, the total evaporation and transpiration for 63.24%, the soil moisture storage for 1.6%. Analysis of the 40-year rainfall data in the 19 counties of Hainan Island during 1951-1990 showed that the large-scale substitution of the natural vegetation with the rubber plantations had no significant effect on the local rainfall in Hainan Island. The main reasons are (1) 80% of the rainfall in Hainan is brought by typhoons; (2) the proportion of 11.6% rubber plantations in total forest coverage in Hainan is not enough to influence the local rainfall in Hainan Island; and (3) although the rubber plantation is artificial vegetation, it has the similar function to the tropical rain forest. Analysis of the total water resource and total GDP of Hainan in 1997 showed that the economic benefit resulted from the water resource was 1.0 RMB Yuan/m3. The value of hydrological of the rubber plantation in Hainan was 113.9 million RMB Yuan/3 when compared with the tropical rain forest. The paper reaches conclusion that the hydrological eco-service function of rubber plantation has been enhanced after transformed from natural vegetation, which includes the natural service and powerful social service.

Objective: To investigate the expression of NF-kappa B following retinal ischemia and reperfusion injury in mice., Methods: Retinal ischemia was induced by elevation of intraocular pressure. Retinal degeneration and atrophy were quantified by an image analysis system. Immunohistochemistry using p65 monoclonal antibody was performed on the retina and co-related with TUNEL labeling., Results: Inner retinal thickness was increased in the initial 24 hours following retinal ischemia and was ascribed to tissue edema, but was significantly decreased by 168 hours after reperfusion. Six hours after retinal ischemia, p65 immunoreactivity was increased in the ganglion cell and the inner nuclear layers, reached a peak at 24 hours, and was parallel to TUNEL labeling. Double labeling with p65 and TUNEL showed partial co-localization of p65 and TUNEL labeling, predominantly in the inner nuclear layer., Conclusions: Activation of NF-kappa B appears to play an important role in retinal degeneration following retinal ischemia and reperfusion injury. The pro- and anti-apoptotic effects of NF-kappa B after retinal ischemia are being further investigated.

The superconducting critical temperature (T(c)) of ferromagnet-superconductor-ferromagnet systems has been predicted to exhibit a dependence on the magnetization orientation of the ferromagnetic layers such that T(AP)(c)>T(P)(c) for parallel (P) and antiparallel (AP) configurations of the two ferromagnetic layers. We have grown CuNi/Nb/CuNi films via magnetron sputtering and confirmed the theoretical prediction by measuring the resistance of the system as a function of temperature and magnetic field. We find an approximately 25% resistance drop occurs near T(c) in Cu0.47Ni0.53(5 nm)/Nb(18)/CuNi(5) when the two CuNi layers change their magnetization directions from parallel to antiparallel, whereas there is no corresponding resistance change in the normal state.

An antiferromagnetic (AF) superlattice of Fe/Cr(211) is used as a model system to study magnetic transitions in a finite-size geometry. With polarization neutron reflectometry the magnetic structure at the surface spin-flop transition and its evolution with field is determined. A domain wall created near the surface penetrates the superlattice with increasing field, splitting it into two antiphase, AF domains. After reaching the center the spin-flopped phase spreads throughout the superlattice. The experimental results are in substantial agreement with theoretical and numerical predictions.

Objective: To observe the role and the timing of EN in the treatment of patients with severe acute pancreatitis (SAP)., Methods: Eleven patients with severe acute pancreatitis underwent systemic nutrition support were studied. EN was given through jejunostomy tube (or Bengmark tube) after a period of PN maintenance. EN started when serum and urine amylase activity returned to normal with regular peristaltic sound, defecation or break wind. The sequence of preparation was as follows: saline glucose-->chemically defined diet-->polymeric diet-->normal diet., Results: In all the patients, none died. The rate of late complications was lower, and the levels of serum albumin and transferritin significantly increased in the post-EN period as compared with the pre-EN period, although the count of lymphocytes was less changed., Conclusions: Nutritional support should be transformed from PN to EN as early as possible during the treatment of patients with severe acute pancreatitis. EN could not only continue sufficient nutritional support, but also avoid the unfavorable effects of long-time PN, thus reducing complications as well as mortality.

The spatial extent zeta(AFM) and strength J(AFM) of the antiferromagnetic (AFM) exchange coupling at buried Gd /Fe interfaces in ferrimagnetic [Gd(50 A)Fe(15,35 A)](15) sputtered multilayers is obtained from combined x-ray resonance magnetic reflectivity and magnetic circular dichroism measurements. zeta(AFM) is 4.1(7) A or approximately 1-2 interatomic distances in bulk Gd and Fe; J(AFM) is 1050(90) K, comparable to the ferromagnetic exchange in bulk Fe.

The appearance of biquadratic exchange coupling between soft Fe and hard SmCo thin layers is found. The remanent magnetization in the Fe layer reorients from parallel to perpendicular with respect to the SmCo easy axis after application of large enough negative field. To explain such an unexpected behavior in contacting ferromagnetic layers a model is proposed based on Slonczewski's fluctuating exchange mechanism. In our samples a partial remagnetization of the hard layer creates fluctuations of the bilinear interactions. The intralayer exchange averaging of the resulting magnetization fluctuations in the soft layer causes the observed biquadratic coupling.

We have studied the effect of magnetic disorder on the magnetization reversal process in thin Co/CoO films. The antiferromagnetic CoO layer allows a reversible tuning of the magnetic disorder by simple temperature variation. For temperatures above a critical temperature T(c), we observe a discontinuous magnetization reversal, whereas smooth magnetization loops occur for T

Background and Purpose: Self-extubation is a potentially life-threatening event, but may also provide an opportunity to wean patients who should have been extubated earlier. The purpose of this study was to determine the risk factors for re-intubation after self-extubation., Methods: The medical charts of 69 self-extubated patients treated in Shin Kong Hospital, Taipei, from September 1996 through August 1998 were reviewed. Demographic data, ventilator settings before self-extubation, arterial blood gas values, and the type of respiratory management used after self-extubation were examined to determine their association with re-intubation., Results: Of the 69 self-extubated patients, 38 fared well without further ventilatory support after self-extubation. Four factors were associated with extubation outcome: 1) mean pre-extubation FiO2 (fraction of inspired oxygen), which was significantly higher in the re-intubated group (RI) than in the not re-intubated group (NRI) (0.48 vs 0.33, p = 0.002)--all self-extubated patients receiving an FiO2 of more than 0.40 were re-intubated; 2) PaO2/FiO2 (ratio of arterial oxygen tension to inspired oxygen concentration), which was lower in the RI group than in the NRI group (259.4 vs 346.4, p = 0.005); 3) requirement for assist/control ventilatory mode--patients needing this type of ventilatory support had a greater likelihood of reintubation than those requiring partial ventilatory support (odds ratio [OR], 3.790; confidence interval [CI], 1.055-13.621; p = 0.041); and 4) female sex (OR 0.188; CI 0.048-0.732; p = 0.016)., Conclusions: About half of self-extubated patients may not require re-intubation. Pre-extubation FiO2, PaO2/FiO2, and ventilator mode, as well as gender, may be useful in determining the likelihood that a self-extubated patient will require re-intubation.

Extubation failure is significantly associated with increased morbidity and mortality in mechanically ventilated patients. In respiratory distress after extubation, non-invasive positive pressure ventilation (NIPPV) has been suggested to avoid the complications of invasive mechanical ventilation. The purpose of this study was to evaluate the effect of early application of NIPPV on extubation outcome. We conducted a prospective study in 93 extubated patients with a mean age of 72.7 +/- 14.7 years (range, 24-93). Elective extubation was performed in 56 patients and unplanned extubation occurred in 37 patients. After extubation, patients randomly received either biphasic positive airway pressure (BIPAP) therapy (n = 47) or unassisted oxygen therapy (n = 46). Non-invasive positive pressure ventilation was delivered via face mask in BIPAP group. Of the 93 extubated patients, 73 (78.5%) were successfully extubated, and 20 (21.5%) had to be re-intubated. There were no significant differences in age, sex, pre-extubation blood gas data between re-intubated patients and those who were not re-intubated. While seven of the 46 patients in the unassisted oxygen therapy group required re-intubation, 13 of the 47 BIPAP-treated patients also required re-intubation. This difference was not statistically significant. The postextubation respiratory management, BIPAP or unassisted oxygen therapy, did not correlate with the extubation outcome, but the elective extubation had significantly better outcome than unplanned extubation. Patients with excessive bronchial secretions and intolerance to the equipment are poor candidates for NIPPV. We conclude that early application of BIPAP support did not predict a favourable extubation outcome. Our experience did not support the indiscriminate use of NIPPV to facilitate ventilator weaning.

In this study, we investigated the modulatory effects of different types of blood cells on hypoxic pulmonary vasoconstrictive (HPV) response and nitric oxide (NO) release in isolated rat lungs. The lungs were perfused at a constant flow with physiologic saline solution (PSS). The changes in pulmonary arterial pressure (PAP) and NO release were observed. Two hypoxic challenges with a 5% CO2-95% N2 gas mixture were carried out in each experiment. Hypoxia induced pulmonary vasoconstriction, as reflected by an increase in PAP (0.88 +/- 0.22 cmH2O). At the same time, NO (342.9 +/- 78.3 mv) release from the lungs was also increased. Addition of white blood cells (WBCs, 0.70 to 0.88 x 10(5)/mL), platelets (1.48 to 1.96 x 10(5)/mL), or red blood cells (RBCs, 4.6 to 6.6 x 10(5)/mL) into the perfusate produced different effects on PAP and NO changes. WBCs decreased the pulmonary vasoconstriction response and this was accompanied by an increase in NO release. Platelets had no significant effects on either PAP or NO. RBCs significantly potentiated the PAP increase and attenuated the NO release. The results indicate that NO release during hypoxia tends to offset pulmonary vasoconstriction and that NO release and HPV response are modulated by different cell elements.

A new software suite, called Crystallography & NMR System (CNS), has been developed for macromolecular structure determination by X-ray crystallography or solution nuclear magnetic resonance (NMR) spectroscopy. In contrast to existing structure-determination programs, the architecture of CNS is highly flexible, allowing for extension to other structure-determination methods, such as electron microscopy and solid-state NMR spectroscopy. CNS has a hierarchical structure: a high-level hypertext markup language (HTML) user interface, task-oriented user input files, module files, a symbolic structure-determination language (CNS language), and low-level source code. Each layer is accessible to the user. The novice user may just use the HTML interface, while the more advanced user may use any of the other layers. The source code will be distributed, thus source-code modification is possible. The CNS language is sufficiently powerful and flexible that many new algorithms can be easily implemented in the CNS language without changes to the source code. The CNS language allows the user to perform operations on data structures, such as structure factors, electron-density maps, and atomic properties. The power of the CNS language has been demonstrated by the implementation of a comprehensive set of crystallographic procedures for phasing, density modification and refinement. User-friendly task-oriented input files are available for nearly all aspects of macromolecular structure determination by X-ray crystallography and solution NMR.

Solvation in macromolecular crystal structures was studied by analyzing X-ray diffraction data of two proteins, penicillopepsin and neuraminidase. The quality of several solvent models was assessed by complete cross-validation in order to prevent overfitting the diffraction data. Radial solvent distribution functions were computed from electron density maps using phases obtained from multiple isomorphous replacement and from the protein's atomic model combined with the best solvent model. Distribution functions were computed around hydrophilic and hydrophobic groups on the protein's surface. Averaging of the distribution functions was performed in order to reduce the influence of noise. The first solvation shell is characterized by a peak in the average distribution functions. At 1.8 A resolution, polar groups show a sharp peak while non-polar groups show a broad one. The distinction between hydrophobic and hydrophilic solvation sites is lost when using lower resolution (2.8 A) diffraction data. Higher-order solvation shells are not observed in the average distribution functions. We hope that site-specific radial distribution functions obtained from high-quality diffraction data will produce a picture of macromolecular solvation consistent with available experimental data and computational results.

Arrays of ferromagnetic nickel and cobalt nanowires have been fabricated by electrochemical deposition of the metals into templates with nanometer-sized pores prepared by nuclear track etching. These systems display distinctive characteristics because of their one-dimensional microstructure. The preferred magnetization direction is perpendicular to the film plane. Enhanced coercivities as high as 680 oersteds and remnant magnetization up to 90 percent have also been observed.