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A universal supervised neural network (NN) relevant to compute the associated critical points of real experiments studying phase transitions is constructed. The validity of the built NN is examined by applying it to calculate the critical points of several three-dimensional (3D) and two-dimensional (2D) models, including the 3D classical O(3) model, the 3D 5-state ferromagnetic Potts model, a 3D dimerized quantum antiferromagnetic Heisenberg model, and the 2D XY model. Particularly, although the considered NN is only trained once on a one-dimensional (1D) lattice with 120 sites, it has successfully determined the related critical points of the studied systems. Moreover, real configurations of states are not used in the testing stage. Instead, the employed configurations for the NN prediction are constructed on a 1D lattice of 120 sites and are based on the bulk quantities or the spin states of the considered models. As a result, our calculations are ultimately efficient in computation, and the application of the built NN in studying the phase transitions of physical systems is extremely broad. Considering the fact that the investigated systems vary dramatically from each other, it is amazing that the combination of these two strategies in the training and the testing stages leads to a highly universal supervised neural network for learning phases of 3D and 2D models. Based on the outcomes presented in this study, it is favorably probable that much simpler but elegant machine learning techniques can be constructed for fields of many-body systems other than the critical phenomena.

The collision between aqueous drops in air typically leads to coalescence after impact. Rebounding of the droplets with similar sizes at atmospheric conditions is not generated, unless with significantly large pressure or high impact parameters exhibiting near-grazing collision. Here we demonstrate experimentally the creation of a non-coalescent regime through addition of a small amount of water-soluble surfactant. We perform a direct simulation to account for the continuum and short-range flow dynamics of the approaching interfaces, as affected by the soluble surfactant. Based on the immersed-boundary formulation, a conservative scheme is developed for solving the coupled surface-bulk convection–diffusion concentration equations, which presents excellent mass preservation in the solvent as well as conservation of total surfactant mass. We show that the Marangoni effect, caused by non-uniform distributions of surfactant on the droplet surface and surface tension, induces stresses that oppose the draining of gas in the interstitial gap, and hence prohibits merging of the interfaces. In such gas–liquid systems, the repulsion caused by the addition of surfactant, as frequently observed in liquid–liquid systems such as emulsions in the form of an electric double-layer force, was found to be too weak to dominate in the attainable range of interfacial separation distances. These results thus identify the key mechanisms governing the impact dynamics of surfactant-coated droplets in air and imply the potential of using a small amount of surfactant to manipulate impact outcomes, for example, to prevent coalescence between droplets or interfaces in gases.

Cost-effective two-dimensional (2D) discrete cosine transform (DCT) and inverse DCT architectures capable of supporting multiple standards of MPEG, H.264 and VC-1 are presented. The proposed core utilises a 1D core and a transposed memory to achieve a low cost design. Multi-level factor share is implemented in conjunction with distributed arithmetic in a system to enable the sharing of the coefficient matrix circuit in order to reduce hardware costs. The proposed approach employs a time-distribution scheme to enable the simultaneous processing of the first and second dimensions to enhance throughput. A high efficiency of this approach was verified by fabricating a test chip using the TSMC 0.18 μm CMOS process. The architecture has an operating frequency of 200 MHz, and throughput of 800 M-pixels/s with a gate count of 44.5 K.

Globalisation and migration have inevitably shaped the objectives and content of medical education worldwide. Medical educators have responded to the consequent cultural diversity by advocating that future doctors should be culturally competent in caring for patients. As frontline clinical teachers play a key role in interpreting curriculum innovations and implementing both explicit and hidden curricula, this study investigated clinical teachers' attitudes towards cultural competence training in terms of curriculum design, educational effectiveness and barriers to implementation.This study was based on interviews with clinical teachers from university-affiliated hospitals in Taiwan on the subject of cultural competence. The data were transcribed verbatim and translated into English. The interviews were analysed using grounded theory to identify and categorise key themes.Five main themes emerged: (i) there was a clear consensus that students currently lack sufficient cultural competence; (ii) the teachers agreed that increased exposure to cultural diversity improved students' cultural understanding; (iii) present curriculum design was generally agreed to be inadequate, and it was argued that devoting space to developing cultural competence across the curriculum would be a worthwhile endeavour; (iv) different methods of performance assessment were proposed; and (v) the main obstacles to teaching and assessing cultural competence were perceived to be a lack of commonly agreed goals, the low priority accorded to it in an overloaded curriculum and the inadequacy of teachers' cultural competence.Eliciting the viewpoints of the key providers is a first step in curriculum innovation and reform. This study demonstrates that clinical teachers acknowledge the need for explicit and implicit training in cultural competence, but there needs to be further debate about the overall goals of such training, the time allotted to it and how it should be assessed, as well as a faculty-wide development programme addressing pedagogical needs.

Background and Objectives TGF-β1 exerts important physiological functions in osteogenesis and chondrogenesis and may be of therapeutic interest. The aim of this work was to develop a scalable purification process of TGF-β1 from virally inactivated human platelets. Study Design and Methods Apheresis platelet concentrates (N = 12) were solvent/detergent (S/D) treated (1% TnBP/1% Triton X-45; 31 °C) and the resulting platelet lysates were clarified by oil extraction and centrifugation, then chromatographed on an anion-exchange DEAE-Sepharose Fast-Flow column equilibrated in a PBS buffer, pH 7·5. The column was washed to eliminate unbound proteins and the S/D agents. Bound proteins were eluted using a 1 M NaCl–PBS buffer pH 7·5 (DEAE-eluate). The content in TGF-β1, PDGF-AB, VEGF, IGF-1, EGF, and b-FGF was measured by ELISA. Proteins, lipids, and S/D agents were assessed. Protein profile was determined by SDS-PAGE under reduced or non-reduced conditions. Results Most proteins, including albumin and immunoglobulins G, A, and M did not bind to the DEAE column as evidenced also by SDS-PAGE. Essentially all PDGF, VEGF, and IGF were in the breakthrough. The DEAE-eluate contained close to 60% of the TGF-β1 at a mean concentration of about 102 ng/ml, whereas EGF, b-FGF were at about 0·72 and 0·18 ng/ml, respectively. The content in TnBP and Triton X-45 was

Background Human platelet growth factors (HPGF) are essential for tissue regeneration and may replace fetal bovine serum (FBS) in cell therapy. No method for the manufacture of standardized virally inactivated HPGF has been developed yet. Study design and methods Platelet concentrates (PC) were subjected to solvent/detergent (S/D) treatment (1% TnBP/1% Triton X-45), oil extraction, hydrophobic interaction chromatography and sterile filtration. Platelet-derived growth factor (PDGF)-AB, -BB and -AA, transforming growth factor-s1 (TGF-s1), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelium growth factor (VEGF) were measured by ELISA. Composition in proteins and lipids was determined, protein profiles were obtained by SDS-PAGE, and TnBP and Triton X-45 were assessed by gas chromatography and high-performance liquid chromatography, respectively. Cell growth promoting activity of HPGF was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay using human embryonic kidney (HEK293A) fibroblast and Statens Seruminstitute rabbit corneal (SIRC) epithelial cell lines. Results The GF preparation contained a mean of 16·66, 2·04, 1·53, 72·19, 0·33, 48·59 and 0·44 ng/ml of PDGF-AB, -BB, -AA, TGF-s1, EGF, IGF-1 and VEGF, respectively. The protein profile was typical of platelet releasates and had less than 2 p.p.m. of residual S/D agents. MTS assay of HEK293A and SIRC cultures showed that the GF preparation at 10% and 0·1% (v/v), respectively, could successfully replace 10% FBS for cell proliferation. Cell-stimulating activity of HPGF on HEK293A was over twice that of PC releasates. Conclusion Standardized and functional virally inactivated HPGF can be prepared from human PC for possible applications in cell therapy and regenerative medicine.

Thin film transistor-liquid crystal display (TFT-LCD) has been used in a wide range of electronic devices. For large-sized and high-density TFT-LCD panel inspection, a high-resolution line scan is demanded. A TFT-LCD panel image at a fine resolution presents very complicated patterns with less regularity. The paper proposes a non-referential defect detection scheme that directly works on the one-dimensional (1D) line images using the Fourier image reconstruction. The 1D grey-level line image is first divided into small segments, each of the length of the repeated period for a given TFT-LCD panel. The divided segments are then combined as a two-dimensional (2D) image. The frequency components corresponding to the 1D background pattern can be easily identified in the 2D Fourier spectrum. By eliminating the frequency components in the 2D Fourier spectrum that represent the periodic structural pattern of the combined 2D image and then back-transforming the image using the inverse Fourier transform, the 2D Fou...

The interfacial reactions between liquid In-49Sn solder and Ni substrates at temperatures ranging from 150°C to 450°C for 15 min to 240 min have been investigated. The intermetallic compounds formed at the In-49Sn/Ni interfaces are identified to be a ternary Ni33In20Sn47 phase using electron-probe microanalysis (EPMA) and x-ray diffraction (XRD) analyses. These interfacial intermetallics grow with increasing reaction time by a diffusion-controlled mechanism. The activation energy calculated from the Arrhenius plot of reaction constants is 56.57 kJ/mol.

Microcapsules for energy storage and/or heat transfer applications containing phase-change materials (PCMs-including n-pentadecane, n-eicosane and a paraffin wax) were successfully produced by emulsifying the PCMs as small droplets in an aqueous, water-soluble urea-formaldehyde pre-polymer solution substantially free of emulsifier while polymerizing the pre-polymer at the interface by acid-catalyst. The core/shell structured microcapsules were also characterized with size distribution analysis, scanning electron microscopy, FTIR spectrometry and differential scanning calorimetry.

The intermetallic compound that appears during the soldering reaction between pure Sn and Ni substrate at temperatures ranging from 250 to 400 °C is analyzed to be Ni 43 Sn 57 . A similar reaction at the Sn-58Bi/Ni interface results in the formation of the Ni 41.5 Sn 57.9 Bi 0.6 phase. At the Sn/Ni and Sn-58Bi/Ni interfaces, each kind of intermetallic compound formation exhibits a similar scallop-type morphology. However, the growth rate of intermetallic compounds at the Sn/Ni interface is greater than that at the Sn-58Bi/ Ni interface. The growth kinetics for both cases is diffusion controlled. The activation energy for the intermetallic growth at the Sn/Ni interface is 43.7 kJ/mol, which is higher than that at the Sn-58Bi/Ni interface (28.3 kJ/mol).

Cyclopropylamine (CPA) is a biochemical active, volatile low carbon polymer. It usually is rendered as a compound, for instance the N-substituted cyclopropylamine, to synthesise many antidepressants or anticancer pharmaceuticals. On the other hand, poly(methyl methacrylate) (PMMA) commonly known as acrylic is a transparent thermoplastic polymer. Because of its nontoxic, stable physical and chemical properties, and because it is inexpensive and easy to processed, PMMA is widely used as structural and adhesive material. In this study, we fabricated CPA-PMMA thin films by plasma polymerisation and investigated the microstructure, surface morphology, optical properties and wettability of films. The plasma polymerisation was conducted in a vacuum chamber powered by a radio frequency supply. The composition of mixed monomers was controlled by the ratio of partial pressure of monomer gases. The deposited films were subjected to the following measurements: surface profiler for the average thickness and deposition rate, Fourier transform infrared (FTIR) spectrometer for the vibrational modes of microstructures; contact angle for the wettability, and UV-Vis-NIR spectrometer for the optical transparency and absorption. Finally these films were prepared for cell culture and the host was chosen to be 3T3 fibroblasts. The culture was assessed by MTT assays to evaluate the cellular viability in culture media and directly on films. Results from cell culture showed that all films are nontoxic and capable of supporting the growth of 3T3 fibroblasts.

Polymerase chain reaction (PCR) amplification was used to detect cytomegalovirus (CMV) in 1000 urine specimens from Chinese newborns for defining the incidence of congenital CMV infection in the Chinese population. The major immediate-early and the late antigen genes of CMV were amplified and detected by gel electrophoresis. There were 18 congenitally infected infants found when tests were performed with one or both primer pairs. Comparing with tissue culture, PCR of both primer sets provided a sensitivity of 94%, a specificity of 100% and a predictive value of positive result of 100%.

Eighty-three isolates from different soil samples exhibited the potential for producing active extracellular phytase. The most active fungal isolate with phytase activity was identified asPenicillium simplicissimum. In shaking culture with enrichment medium, the highest extracellular phytase activity of the producing strain was 3.8 U/mL. The crude enzyme filtrate was purified to homogeneity using ultrafiltration. IEC and gel filtration chromatography. The molar mass of the purified enzyme was estimated to be 65 kDa on SDS-PAGE. The saccharide identification with periodic acid-Schiff reagent (PAS) and activity recognition by l-naphthyl phosphate was all positive. The isoelectric point of the enzyme, as deduced by isoelectric focusing, was pH 5.8, the optimum pH and temperature being pH 4.0 and 55°C, respectively. The purified enzyme revealed broad substrate specificity and was strongly inhibited by Fe2+, Fe3+ and Zn2+; however, no inhibition was found by EDTA and PMSF. Phytase activity was inhibited when 2 mmol/L of dodecasodium phytate was added and theK m for it was determined to be 813 mmol/L.

Polyester-based polyurethanes were synthesized from 4,4′-methylenebis(phenyl isocyanate) (MDI) with butanediol as a chain extender and low molecular weight polyester–diol as a soft segment. Two polyesters were used in the synthesis of polyurethanes. One of the polyesters was synthesized from adipic acid and 1,6-hexanediol, which had an even number of carbon atoms. The other polyester was synthesized from pimelic acid and 1,5-pentanediol, which had an odd number of carbon atoms. The effect of even carbon monomers and odd carbon monomers of polyester soft segments on the phase segregation of soft and hard segments was studied by DSC (differential scanning calorimetry) and FTIR (Fourier transform infrared spectroscopy). © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2095–2104, 1999

The morphologies and growth kinetics of intermetallic compounds for the interfacial reaction between liquid In and solid Ni substrate in the temperature range from 225 to 500°C are examined in this study. Experimental results showed that the thickness of intermetallic compounds formed during the Ni(s)/In(1) interfacial reaction increased with the reaction temperature and the square root of reaction time. The x-ray diffraction pattern revealed the formation of intermetallic compounds Ni10In27 (T 300°C). Moreover, the activation energies for the interdiffusion of Ni and In atoms in the Ni10In27 and Ni2In3 are 94.74 and 33.51 kJ/mol, respectively. Using the Ta thin film as a diffusion mark, the formation mechanism of intermetallic compounds during interfacial reaction was clarified.

Polyester based polyurethanes were synthesized from 4,4′-Methylene bis(phenyl isocyanate) (MDI) with butanediol as a chain extender. The polyesters with various mole ratios of -CH3 side chain were synthesized from adipic acid and glycols which were mixtures of various mole ratios of hexanediol and 1,2-propanediol. The effect of -CH3 content of polyester on the crystallinity of hard segment and physical properties of polyurethanes was studied by DSC (differential scanning calorimetry) and TMA (thermal mechanical analysis).

The growth-promoting activity of GH, the principal hormonal determinant of body size, is mediated by insulin-like growth factor I (IGF-I). Most of the IGF-I in plasma circulates in a 150-kDa complex that contains IGF-binding protein-3 (IGFBP-3) and an acid-labile subunit (ALS). The 150-kDa complex serves as a reservoir of IGF-I and determines its bioavailability to the tissues. Formation of the 150-kDa complex depends upon the synthesis of ALS, which is synthesized primarily in liver and is regulated by GH. The present study demonstrates that GH stimulates ALS gene transcription in rat liver and ALS promoter activity in a rat hepatoma cell line. ALS messenger RNA (mRNA) and ALS nuclear transcripts were decreased to similar extents in the livers of GH-deficient hypophysectomized rats. GH increased hepatic ALS mRNA within 3–4 h to about 65% of the levels seen in sham-operated control rats. To confirm that GH stimulated ALS gene transcription, we transiently transfected an ALS promoter-luciferase reporter gene construct into H4-II-E rat hepatoma cells and primary rat hepatocytes. Recombinant human GH (hGH) stimulated promoter activity about 3-fold. In contrast, basal promoter activity was lower, and GH stimulation was absent when the ALS reporter construct was transfected into GH-responsive 3T3-F442A mouse preadipocyte fibroblasts. GH stimulation of ALS promoter activity in H4-II-E cells was mediated by functional GH receptors; nonprimate (rat and bovine) GH gave identical stimulation to hGH, and stimulation by hGH occurred at physiological concentrations. Reverse transcriptase-PCR analysis indicated that GH receptor mRNA was present in H4-II-E cells at approximately 40% of the level seen in rat liver. GH also induced the expression of the endogenous c-fos gene, indicating that the signaling pathway necessary for the activation of gene expression by GH was intact in H4-II-E cells. Thus, H4-II-E cells are a GH-responsive liver cell line that should provide a useful system in which to study the molecular mechanism of transcriptional regulation by GH of ALS and other hepatic genes.

The PC12 cell line established from a rat pheochromocytoma has been extensively studied as a model of neuronal differentiation. Insulin-like growth factor-I (IGF-I) and IGF-II are mitogenic for PC12 cells under serum-starved conditions. IGF activity is modulated by a family of six IGF-binding proteins (IGFBPs). It recently was reported that PC12 cells produced an IGFBP that had a marked preferential binding affinity for IGF-II over IGF-I. We now show that the main IGFBP produced by PC12 cells is rat IGFBP-6 and compare its properties with those of human IGFBP-6. The predominant IGFBP in medium conditioned by undifferentiated and differentiated PC12 cells migrated on sodium dodecyl sulfate-12% polyacrylamide gel electrophoresis with an apparent molecular mass of 22.5-25 kilodaltons and was recognized by polyclonal antiserum to rat IGFBP-6 by immunoblotting. Rat IGFBP-6 mRNA (1.4 kilobases) was detected by Northern hybridization of total RNA extracted from PC12 cells using a rat IGFBP-6 cDNA probe. Rat IGFBP-6, like human IGFBP-6, is O-glycosylated; incubation with neuraminidase, fucosidase, and O-glycanase reduced its apparent molecular mass to 21 kilodaltons. Competitive binding studies of rat and human IGFBP-6 with [125I]IGF-II and unlabeled IGF-II or IGF-I demonstrated that both IGFBPs bound IGF-II with similar affinities (Ka, 1.5-1.8 x 10(11) M-1) and bound IGF-I with approximately 25- to 35-fold lower affinity than IGF-II. Thus, differences in amino acid sequence, such as deletion of nine amino-terminal residues (including two conserved cysteine residues) in rat IGFBP-6 compared with human IGFBP-6, do not alter its binding characteristics. PC12 cells should provide a useful system to define the regulation of IGFBP-6 expression and the role of IGFBP-6 in modulating IGF action.

The insulin-like growth factor-binding proteins (IGFBPs) are a family of six proteins that modulate the biological activity of IGF-I and IGF-II and determine their bioavailability to tissues. One of the IGFBPs, IGFBP-1, is distinctive in the dynamic response of its levels in human plasma to metabolic changes. Parallel changes occur in IGFBP-1 mRNA and IGFBP-1 transcription in rat liver. Using the well differentiated H4-II-E rat hepatoma cell line as a model system, we demonstrated previously that IGFBP-1 transcription is positively regulated by dexamethasone and negatively regulated by insulin. We now examine the effect of the protein synthesis inhibitor, cycloheximide, on the hormonal regulation of IGFBP-1 gene expression. Preincubation of H4-II-E cells with 10.7 microM cycloheximide for 1.5 h did not prevent the induction of IGFBP-1 mRNA and IGFBP-1 transcription (determined in nuclear run-on assays) by dexamethasone. By contrast, cycloheximide treatment abolished the decrease in IGFBP-1 mRNA induced by insulin. Insulin rapidly decreased IGFBP-1 transcription in the absence of cycloheximide (> 50% inhibition in 20 min) and caused a similar decrease in cells pretreated with cycloheximide. Cycloheximide alone also decreased IGFBP-1 transcription. Similar results were observed with a second protein synthesis inhibitor, anisomycin, which also prevented the insulin-induced decrease in IGFBP-1 mRNA without abolishing the insulin-induced inhibition of IGFBP-1 transcription. These results suggest that although insulin decreases IGFBP-1 gene transcription in the presence of protein synthesis inhibitors, IGFBP-1 mRNA levels are maintained because of stabilization of the mRNA. Stabilization was demonstrated directly in actinomycin D-treated cells, where the t1/2 of IGFBP-1 mRNA increased from approximately 2 to approximately 20 h in the presence of cycloheximide; insulin did not affect IGFBP-1 mRNA turnover. Thus, cycloheximide-sensitive labile proteins contribute to the maintenance of basal IGFBP-1 promoter activity and the rapid turnover of IGFBP-1 mRNA, which determine the dynamic regulation of IGFBP-1 gene expression.

Insulin-like growth factor-binding protein-1 (IGFBP-1) can inhibit or potentiate IGF action. The biological activity of IGFBP-1 is determined by many factors, including its abundance in tissues and plasma, posttranslational modifications, and localization. IGFBP-1 levels in human plasma are highly regulated. They are increased after acute fasting and in diabetes, and are rapidly reversed by refeeding and insulin treatment, respectively. Similarly, IGFBP-1 mRNA is increased in the liver of severely diabetic and ketotic rats and decreased after 4 days of insulin treatment. Insulin rapidly decreases IGFBP-1 mRNA and IGFBP-1 transcription in rat hepatoma cells. The present study asks whether the increase in IGFBP-1 mRNA in diabetic rat liver reflects increased gene transcription, whether insulin decreases IGFBP-1 mRNA through a transcriptional or posttranscriptional mechanism, and whether this decrease is sufficiently rapid to account for the dynamic fluctuations in plasma IGFBP-1. Rats were injected ip with 100 mg/kg streptozotocin and used 7 days later when they were hyperglycemic and failed to gain weight, but were not ketotic. Hepatic IGFBP-1 mRNA levels were 13.6 +/- 5.3-fold greater in diabetic than control liver and decreased to the low levels in nondiabetic controls within 1 h after insulin treatment. In run-on transcription assays, IGFBP-1 transcription was 12.6 +/- 1.5-fold greater in nuclei from diabetic than control liver and decreased to low control levels by 1 h after insulin injection. Normalization of hepatic IGFBP-1 mRNA in insulin-treated diabetic animals did not require restoration of euglycemia. IGFBP-1 mRNA and IGFBP-1 gene transcription also were increased in the kidney of diabetic ketotic rats. We propose that the dynamic regulation of IGFBP-1 gene transcription in diabetes and after insulin treatment, by determining the availability of IGFBP-1 in tissues and plasma, may be a critical factor in the modulation of IGF action.

The bioavailability and action of the insulin-like growth factors (IGFs) are determined by specific IGF-binding proteins (IGFBP) to which they are complexed. Complementary DNA clones have been isolated that encode three related IGFBPs: human IGFBP-1 (hIGFBP-1), human IGFBP-3 (hIGFBP-3), and rat IGFBP-2 (rIGFBP-2). IGFBP-1 and IGFBP-3 are regulated differently in human plasma, suggesting that they have different functions. In order to study the molecular basis of the regulation of the different IGFBPs, we have identified a panel of rat cell lines that express a single predominant binding protein and developed an assay strategy to distinguish the different binding proteins. Proteins in conditioned medium were examined by ligand blotting, and by immunoprecipitation and immunoblotting using antibodies to rIGFBP-2 and hIGFBP-1; RNAs were hybridized to cDNA probes for rIGFBP-2 and hIGFBP-1. 1) C6 glial cells and B104 neuroblastoma cells express an approximately 40 kilodalton (kDa) glycosylated binding protein that most likely represents rIGFBP-3, the binding subunit of the 150 kDa IGF: binding protein complex in adult rat serum. The C6 and B104 binding proteins do not react with antibodies to rIGFBP-2, and RNAs from C6 and B104 cells do not hybridize to cDNA probes for rIGFBP-2 or hIGFBP-1. 2) BRL-3A, Clone 9, and TRL 12-15 cell lines derived from normal rat liver express rIGFBP-2, a 30 kDa nonglycosylated IGF-binding protein that is recognized by antibodies to rIGFBP-2 but not by antibodies to hIGFBP-1. RNAs from these cells hybridize to a rIGFBP-2 cDNA probe, but not to a hIGFBP-1 probe. 3) H35 rat hepatoma cells express a 30 kDa nonglycosylated IGFBP that is presumptively identified as rIGFBP-1. It does not react with antibodies to rIGFBP-2, but is recognized by polyclonal and monoclonal antibodies to hIGFBP-1. RNA from H35 cells hybridizes to a hIGFBP-1 cDNA probe, but not to a rIGFBP-2 probe. Expression of rIGFBP-1 by the H35 cell line has enabled us to establish and validate specific assays for this protein that allow us to study its regulation in intact rats. Identification of a panel of rat cell lines expressing specific IGFBPs should be useful in elucidating the molecular mechanisms of IGFBP regulation.

In order to obtain particulate methane monooxygenase (pMMO)-enriched membranes from Methylococcus capsulatus (Bath) with high activity and in high yields, we devised a method to process cell growth in a fermentor adapted with a hollow-fiber bioreactor that allows easy control and quantitative adjustment of the copper ion concentration in NMS medium over the time course of cell culture. This technical improvement in the method for culturing bacterial cells allowed us to study the effects of copper ion concentration in the growth medium on the copper content in the membranes, as well as the specific activity of the enzyme. The optimal copper concentration in the growth medium was found to be 30 to 35 μM. Under these conditions, the pMMO is highly expressed, accounting for 80% of the total cytoplasmic membrane proteins and having a specific activity as high as 88.9 nmol of propylene oxide/min/mg of protein with NADH as the reductant. The copper stoichiometry is ∼13 atoms per pMMO molecule. Analysis of other metal contents provided no evidence of zinc, and only traces of iron were present in the pMMO-enriched membranes. Further purification by membrane solubilization in dodecyl β- d -maltoside followed by fractionation of the protein-detergent complexes according to molecular size by gel filtration chromatography resulted in a good yield of the pMMO-detergent complex and a high level of homogeneity. The pMMO-detergent complex isolated in this way had a molecular mass of 220 kDa and consisted of an αβγ protein monomer encapsulated in a micelle consisting of ca. 240 detergent molecules. The enzyme is a copper protein containing 13.6 mol of copper/mol of pMMO and essentially no iron (ratio of copper to iron, 80:1). Both the detergent-solubilized membranes and the purified pMMO-detergent complex exhibited reasonable, if not excellent, specific activity. Finally, our ability to control the level of expression of the pMMO allowed us to clarify the sensitivity of the enzyme to NADH and duroquinol, the two common reductants used to assay the enzyme.

A regularized surface reconstruction neural network approach to perform robust invariant 2D/3D object recognition and motion estimation is presented. By efficiently embedding the whole 2D/3D image space into a neural network parametric representation, it is possible to elegantly duplicate the human's mental image transform and matching capability in performing the rotating and scaling of objects as suggested by the studies of experimental psychology. The preliminary simulations of applying this technique to invariant 2D target classification and 3D object motion estimation using sparse range data collected from a single perspective view are encouraging. >

The uvrB gene of Xanthomonas campestris pv. campestris, a Gram-negative plant pathogenic bacterium inhabiting soil and infected plants, was cloned and sequenced. This gene has the capacity to encode a polypeptide of 673 amino acid residues with a calculated molecular mass of 75.9 kDa. Its deduced amino acid sequence shows a high degree of similarity and possesses domain conservation to those of bacterial UvrB. The uvrB mutant, isolated by gene replacement, is extremely sensitive to ultraviolet irradiation. Like the situation in the X. campestris pv. campestris recA gene, no SOS box is present upstream of the uvrB gene. Northern blotting and transcriptional fusion assay with lacZ indicated that X. campestris pv. campestris uvrB is expressed constitutively at high levels and cannot be further induced by UV irradiation. These results suggest a regulatory mechanism different from that for the expression of Escherichia coli uvrB. Using a gene-tagging strategy in conjunction with pulsed-field gel electrophoresis, the uvrB gene was located near 1 o'clock on the X. campestris pv. campestris 17 chromosome (4.8 Mb) map, which is far apart from the lexA-recA-recX cluster near 5 o'clock.

Xanthomonas campestris pv. campestris produces great amounts of an exopolysaccharide (EPS), xanthan gum. Eight eps loci involved in biosynthesis of the EPS were previously located in the chromosome map of strain Xc17. In this study, the eps8 region was cloned, sequenced and found to contain a crp homologue whose deduced amino acid sequence possesses similarity to that of the cyclic AMP receptor protein of bacteria, with the highest identity (97%) being shared with the X. campestris pv. campestris B-1459 clp gene previously shown to be involved in pathogenicity and regulation of the production of xanthan, extracellular enzymes, and pigment (de Crecy-Lagard V., Glaser P., Lejeune P., Sismeiro O., Barber C.E., Daniels M.J., and Danchin A., J. Bacteriol. 172:5877-5883, 1990). Based on sequence identity, pleiotropic effects of the mutation, the ability to complement an Escherichia coli cya crp mutant, and Southern hybridization detecting a single copy in the chromosome, we propose this eps8 gene to be the Xc17 clp. In addition to the previously reported properties, a clp mutant (AU56E) cannot be plaqued with filamentous phage phiLf, although it retains the capability to support phiLf DNA replication and release authentic phage particles upon electroporation of the RF DNA. Infective center assays demonstrated that the frequency of infection is 460- to 7,500-fold lower in AU56E compared to that in the wild-type Xc17. Electron microscopy, which showed no surface appendages other than the monotrichous flagellum, confirmed that AU56E drastically diminishes in the efficiency of phage adsorption. These results suggest Clp to be regulating the biosynthesis of the primary receptor, most likely a type IV pilus. Upstream to clp is a homologue of the E. coli speD gene required for spermidine synthesis. Mutation of the clp flanking regions and transcriptional analyses suggest clp to be monocistronic and the only gene contained at the eps8 locus.

Rad is the prototypic member of a family of novel Ras-related GTPases that is normally expressed in heart, skeletal muscle, and lung and that has been shown to exhibit a novel form of bi-directional interaction with the nm23 metastasis suppressor. In the present study, we have investigated the expression of Rad in normal and neoplastic breast tissues by Western blot and immunohistochemistry and the functional effect of altered Rad expression in breast cancer cell lines. We found that, although Rad is frequently expressed in normal breast tissue (23/30 Rad+ve), expression is usually lost in adjacent invasive carcinoma (8/30 Rad+ve; P0.0001). However, where Rad expression persists in a small proportion of tumors, it is associated with higher grade, larger size, and extensive axillary nodal involvement (n = 48; P = 0.035, P = 0.016, P = 0.022, respectively). Furthermore, Rad is also highly expressed in a breast cancer cell line with high tumorigenic and metastatic potential (MDA-MB231). To further examine the role of Rad in breast cancer, we stably transfected a Rad-ve breast cancer cell line (MDA-MB435). We observed an increase in growth and marked increased colony formation in soft agar in vitro (P0.05) and an increase in tumor growth rate in nude mice (P0.05). Moreover, coexpression of nm23 with wild-type Rad inhibited the effect of Rad on growth of these cells in culture and markedly inhibited tumor growth in vivo. Additional transfection studies with mutated Rad cDNAs revealed that the growth-promoting effects of Rad appeared to be mediated through its NH2- and COOH-terminal regions, rather than its GTPase domain, and might involve acceleration of cell cycle transition. These findings suggest that Rad may act as an oncogenic protein in breast tissues and demonstrate a potential mechanism by which interaction between Rad and nm23 may regulate growth and tumorigenicity of breast cancer.

Since its introduction and development in the 1960s, laparoscopic cholecystectomy has become widely accepted by the medical community and the public as the treatment of choice for various gallbladder disorders. We present a 46-year-old male who underwent laparoscopic cholecystectomy, during which inadvertent penetration of the first trocar resulted in injury of the abdominal aorta and then hypovolemic shock ensured. The time from notification of shock by the anesthesiologist to switch of procedure to exploratory laparotomy for stanching hemorrhage was twenty minutes. During the intervention, blood loss was over 3,000 ml and despite rapid infusion of plasma expander, blood pressure could only be maintained between 40/18 to 60/20 mmHg. After the patient became stabilized and blood pressure was elevated to acceptable levels, conventional cholecystectomy was performed instead. Perioperative blood loss of 7,300 ml was estimated. In total, the patient received 24 units of packed red blood cells, 12 units of fresh frozen plasma, and 12 units of platelets. After the operation, the patient was transferred to the surgical ICU for further observation. For 24 h at the ICU, blood pressure remained unstable, urine output decreased gradually, and scrotal and leg edema developed. Forty-four h after admission to the surgical ICU, arrhythmia and profound hypotension were noted and cardiac arrest ensued. After resuscitation for 2 h, the patient could not be revived and succumbed to cardiovascular decompensation secondary to acute renal shutdown and continuous retroperitoneal hemorrhage.

Impairment of higher cortical functions is usually not considered as a typical presentation of lacunar infarction. However, a small discrete lesion at strategically important locations may produce memory loss and mental changes. We report 4 patients with lacunar infarctions manifested as acute amnesia and mental changes. One patient had left thalamic infarction, one had left capsular genu infarction, one had right capsular genu infarction, and one had left capsular genu infarction extending to the ipsilateral thalamus. The mental and memory impairment was transient in one patient but was persistent in the other 3 patients. Our report reconfirms that a lacunar infarction can cause impairment of higher cortical functions.

The complete nucleotide sequence (1,851 bp) was determined for the Xanthomonas campestris pv. vesicatoria plasmid pXV64. Sequence analysis revealed an intergenic region (IG) of 355 bp and two oppositely running open reading frames, ORF1 and ORF2, encoding polypeptides of 39 and 16 kDa, respectively. While the function of ORF2 is not known, ORF1 is suggested to be the gene encoding Rep protein based on (i) similarity in amino acid sequence to that of the gene II protein (gIIP) of filamentous phage 12-2, (ii) presence of a sequence in the ori-containing region which is similar to the sequence around the Rep nicking site in some rolling circle-replicating replicons, and (iii) ability to support replication in trans of the region containing pXV64 ori (392 bp) which is located within the region including IG and a short stretch in the N-terminus of ORF2.

A 62-year-old diabetic women developed acute quadriparesis. Her first symptom was clumsiness of the right limbs, which was followed shortly after by quadriparesis with severe left-sided symptoms. Sensory examination showed pinprick and thermal sensation deficits below the left T6 and right T8 dermatomes. An intramedullary infarction in the cervical cord at C5 to C6 levels was demonstrated by serial magnetic resonance imaging (MRI) studies with Gadolinium-DTPA (Gd-DTPA) enhancement. Based on the findings from this patient and 20 patients with spinal cord infarction reported in the literature, it was concluded that spinal cord infarct lesions are characterized by negative Gd-DTPA enhancement at the acute and chronic stages and positive enhancement at the subacute stage, 1 to 4 weeks after the onset of infarction.