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Seminalplasmin (SPLN) is a 47‐residue protein isolated from bovine seminal plasma having potent antimicrobial activity against a broad spectrum of microorganisms. SPLN, also known as caltrin, acts as a calcium transport regulator in bovine sperms. Analysis of the sequence of SPLN reveals a 27‐residue stretch with the sequence SLSRYAKLANRLANPKLLETFLSKWIG more hydrophobic than the rest of the protein. It is demonstrated that a synthetic peptide corresponding to this 27‐residue segment has antimicrobial activity comparable to that of SPLN. It does not exhibit hemolytic activity at concentrations where antibacterial activity is observed. Since P27 can be conveniently obtained in large amounts by chemical synthesis, it could serve not only as a starting compound to obtain peptides with improved antibacterial activity but also to understand the role of SPLN in reproductive physiology.

ABSTRACTRemoval of toxic heavy metals from wastewaters and their recovery is a challenging problem. Simultaneous and synergistic batch extraction from water of copper present as a cation (Cu2+) and Cr6+present as an anion (HCr2O) into a mixed solvent extraction system have been studied. The mixed solvent extraction system consists of the diluent kerosene, the cation exchanger LIX 84, and trioctyl amine (TOA) which extracts anions via ion-pair formation with a proton. Highly efficient extraction has been achieved for both copper and chromium. Simultaneous extraction of two cations, Cu2+and Zn2+, as well as the anionic form of Cr6+, (HCr2O), has also been studied using mixtures of LIX 84, di-2-ethylhexyl phosphoric acid (D2EHPA), and TOA in the diluent kerosene. For an appropriate mixture composition, all three metallic ionic species can be simultaneously extracted with high efficiency. The extent of complexation between the basic extractant, TOA, and the acidic extractant/s is important in determining the extraction efficiency. A model developed for the extraction of Cu2+using a mixed solvent extraction system provides a reasonable description of the observed extraction behavior and provides a first step for modeling.

Three visible spectrophotometric methods (A-C) for the determination of Methotrexate (MTX) in pharmaceutical formulations are described. Method A is based on the reduction of Fe(III) to Fe(II) by the drug which forms a coloured complex (max: 510 nm) with 1,10-phenanthroline (PHEN). Method B involves the reduction of Folin-Ciocalteu (F-C) reagent by the drug and the reduced species produced possesses a characteristic intense blue colour (max: 770 nm). Method C is based on the coupling reaction through the involvement of an aromatic secondary amino group in p-N-methylaminobenzoylglutamic acid (released through reduction of the drug with zinc and HCl) with 1,2-naphthaquinone-4-sulfonic acid sodium salt (NQS) to form a coloured product (max: 500 nm). Regression analysis of a Beer's plot showed good correlation in the concentration ranges of 1.0–8.0, 2.0–14.0 and 25.0–300.0 g.ml-1 for methods A,B and C, respectively. No interference was observed from the additives and the applicability of the methods was tested by analysing the pharmaceutical formulations containing methotrexate. Recoveries were 98.9–101.1%.

A spectrophotometric method is described for the determination of Nicoumalone and Acebutolol hydrochloride based on the formation of molecular complex with the reduction product of Nicoumalone or hydrolysis product of Acebutolol hydrochloride and p-N-methyl benzoguinone monoimine [formed in situ from met01 (p-N-methylaminophenol sulfate) and potassium permanganate, PMBQMI] at pH 3.3. Quantitative measurements were made at the maximum absorption of 525 nm. Beer's law is obeyed in the range of 5–50 g ml-1 and 5–60 g ml-1 for Nicoumalone and Acebutolol hydrochloride respectively. The proposed method is comparable with the reference method when applied to pharmaceutical preparations, and tablets, An average percentage recovery of 99.5 ± 0.8 was obtained.

The partially parabolized Navier-Stokes equations are a set of approximate governing equations that are applicable to flows possessing a predominant flow direction and are obtained when terms representing viscous diffusion of momentum in the main flow direction are dropped from the full Navier-Stokes equations. These reduced equations differ from Prandtl's boundary-layer equations in that no further simplifying assumptions have been made regarding the transverse pressure gradients and transverse momentum equations. Hence, transmission of influences through pressure can be significant even against the main flow direction. The present study was motivated by an interest in evaluating the merits of this reduced flow model for conditions where the boundary-layer equations are known to be inadequate. The principle features of a numerical scheme used to solve the partially parabolized Navier-Stokes equations are described. Results for the flow in the inlet region of a channel are compared with solutions to the full Navier-Stokes equations and the boundary-layer equations over a range of Reynolds numbers from 0.5 to 7500. The solutions to the partially parabolized equations were generally within 5% of the solutions to the full Navier-Stokes equations for Reynolds numbers as low as 10.

The problem of convective diffusion from and reaction within the circulating flow inside a two-dimensional rectangular cavity is studied. The circulation is of the type induced by an external flow. Mass transfer occurs across the interface between the cavity and the external flow. A reactant may diffuse into the cavity from the external flow. The equations of steady motion and transient convective diffusion and chemical reaction are solved numerically. An enhancement factor is defined which quantifies the effectiveness of internal circulation in promoting diffusion and reaction. The dependence of this enhancement factor on geometry (cavity aspect ratio), Peclet number, and kinetic parameters is displayed.

Primary papillary serous carcinoma of the peritoneum (PPC) is clinically and histologically similar to advanced stage epithelial ovarian carcinoma. PPC classically presents with widespread intraperitoneal dissemination, superficial invasion, and minimal ovarian involvement. Surgical cytoreduction and combination chemotherapy utilized for patients with epithelial ovarian carcinoma have produced varying results for patients with PPC. These differences in response may be secondary to the stage of disease or due to biological differences in metastatic behavior between these carcinomas. In this study, short-term primary cultures of PPC and epithelial ovarian carcinoma (OVCA) were compared to enable biochemical comparison with respect to components of the metastatic cascade including adhesion, migration, and proteinase activity. These data demonstrated similar properties in adhesive profiles of PPC and OVCA, with preferential adhesion to type I collagen and vitronectin. Matrix-degrading proteinases including matrix metalloproteinases (MMP)-2, MMP-9, and urinary-type plasminogen activator were produced by both cell types. PPC migration was stimulated by multiple extracellular matrix proteins, whereas OVCA cells demonstrated maximal migration on type I collagen coated surfaces. Together our data suggest biochemical similarities between PPC and OVCA with respect to individual components of the metastatic cascade.

A numerical study of heat transfer in 90 deg, constant cross section curved duct, steady, laminar, flow is presented. The work is aimed primarily at characterizing the effects on heat transfer of duct geometry and entrance conditions of velocity and temperature by considering, especially, the role of secondary motions during the developing period of the flow. Calculations are based on fully elliptic forms of the transport equations governing the flow. They are of engineering value and are limited in accuracy only by the degree of computational mesh refinement. A comparison with calculations based on parabolic equations shows how the latter can lead to erroneous results for strongly curved flows. Buoyant effects are excluded from the present study so that, strictly, the results apply to heat transfer flows in the absence of gravitational forces such as arise in spacecraft.

A simple and sensitive method for the spectrophotometric determination of bio-active compounds (drugs and non-nutritive sweeteners) containing reactive functional groups, viz., aromatic primary amine (drugs: Dapsone, Sulphamethoxazole), aromatic secondary amine (drug: Pindolol), aliphatic secondary amine (non-nutritive sweetener: Cyclamate), acid hydrazide (drug: Isoniazid) and thiol (drug: Captopril), is proposed. The method involves the addition of excess of sodium nitrite to the compound in the presence of 0.25 M hydrochloric acid solution and the unreacted nitrous acid is determined by the measurement of corresponding decrease in the absorbance of cresyl fast violet acetate (max : 555 nm), the most suitable one out of several dyes tested. This method was applied for the determination of bio-active compounds in commercial samples. (drugs: pharmaceutical formulations; non-nutritive sweetener (cyclamate): foodstuffs). The newly proposed method enabled the determination of the bio-active compounds in microgram quantities (0.1 - 0.5 g/ml). Standard deviation values evaluated through replicate determinations were found to be < 0.5 mg per dose (RSD : 0.5 - 1.2%). The common excipients do not effect the determination of the drugs in pharmaceutical formulations. Many of the usually occurring additives in food stuffs are tolerated to a very high level in the determination of cyclamate in beverages, syrup, ice candy and ice cream. The validity of the method was tested against the reference method. Recoveries to the tune of 99.2 - 101.1% were observed by adopting this method.

The authors analyzed the secretion of extracellular matrix-degrading proteinases, including urinary-type plasminogen activator (u-PA), matrix metalloproteinase-2 (MMP-2, gelatinase A), and MMP-9 (gelatinase B), by short term primary cultures of epithelial ovarian carcinoma cells derived from primary ovarian tumors, intraperitoneal metastases, or ascites. The presence of these enzymatic activities in samples of ascites was also evaluated. The effect of adhesive substratum on proteinase production was determined. A coupled spectrophotometric assay was utilized to evaluate the initial rate of plasminogen activation by u-PA in conditioned medium; this involved monitoring the activity of generated plasmin with a colorimetric substrate. MMP activity was evaluated by gelatin zymography. Ascitic fluids from 18 patients contained u-PA, MMP-2, and MMP-9. However, short term primary cultures of cells derived from primary ovarian tumors (OVET), metastatic lesions (OVEM), or ascites (OVEA) produced very low levels of u-PA. Production of u-PA by OVET and OVEM cells was regulated by adhesive substratum. Conditioned media from OVET, OVEM, and OVEA cells contained high levels of both MMP-2 and MMP-9. MMP-9 levels decreased with increasing passage in culture, whereas MMP-2 activity was maintained. Production of neither MMP-2 nor MMP-9 was regulated by adhesive substratum. These results demonstrate that primary cultures of epithelial ovarian carcinoma cells derived from three distinct anatomic locations produce MMP-2 and MMP-9, with low level secretion of u-PA. These data suggest that MMPs, particularly MMP-2, may play a significant role in the intraperitoneal invasion of ovarian carcinoma cells. Cancer 1997; 80:1457-63. © 1997 American Cancer Society.

Added mass and fluid damping coefficients for vibrations of an inner cylinder that is enclosed by a concentric outer cylinder are determined by finite element analysis of the unsteady, laminar, incompressible flow in the annulus. Continuously deforming space-time finite elements are used to track the moving cylinder and the changing shape of the space domain. For small cylinder vibration amplitudes, the present results agree well with the work of earlier investigators who solved the linearized Navier-Stokes equations on a fixed mesh. Fluid damping coefficients are shown to increase with vibration amplitude. Added mass coefficients may either increase or decrease with increasing vibration amplitude.

An implicit finite difference scheme in primitive variables is used for analysis of unsteady, laminar flow past transversely vibrating cylinders. Predictions of flow past an impulsively started cylinder and of vortex shedding from a stationary cylinder agree well with experimental data. Calculations of flow past a transversely vibrating cylinder were within the range of experimental scatter only for small vibration amplitudes. Several experimentally observed phenomena such as drag amplification and reduction in excitation lift coefficient at large vibration amplitudes were numerically predicted.

The urokinase-urokinase receptor system plays a dominant role in the degradation and invasion of extracellular matrix (ECM) by tumor cells. In this system, urokinase bound to its cell receptor converts plasminogen to plasmin, a broad-spectrum serine protease that participates in the degradation and invasion of connective tissues by tumor cells. In this study, we evaluated whether these activities of plasmin are inhibited by a newly characterized human 32 kDa recombinant serine protease inhibitor called trypsin/tissue factor pathway inhibitor-2 (rTFPI-2). We found that rTFPI-2 dose-dependently inhibited fluid-phase plasmin as well as plasmin generated on the ECM and/or the cell surface of HT-1080 fibrosarcoma cells. The degradation of radiolabeled matrix as well as Matrigel invasion by these tumor cells is also inhibited by rTFPI-2 in a dose-dependent fashion. We have reported that rTFPI-2 is identical to 33 kDa extracellular matrix-associated serine protease inhibitor (33 kDa MSPI), whereas the 31 and 27 kDa MSPIs are under-glycosylated forms of the 33 kDa MSPI. We therefore evaluated the ability of MSPIs from the ECM of dermal fibroblasts to inhibit plasmin and found that the plasmin activity was effectively blocked by the MSPIs. We have also evaluated whether the HT-1080 cells synthesize and secrete the MSPIs and found that the synthesis and secretion of the MSPIs was undetectable in these cells. Collectively, our results suggest that rTFPI-2/33 kDa MSPI inhibits plasmin on the tumor cell and ECM surfaces as well as the degradation and invasion of matrix by HT-1080 fibrosarcoma cells. Int. J. Cancer 76:749–756, 1998.© 1998 Wiley-Liss, Inc.

Indolicidin, a 13‐residue antimicrobial peptide isolated from cytoplasmic granules of bovine neutrophils, exhibits activity against Gram‐positive and Gram‐negative bacteria as well as fungi. Although indolicidin is bactericidal and permeabilizes the bacterial membranes, it does not lyse the bacterial cells. We examined the effect of bactericidal concentrations of indolicidin on the morphology of Escherichia colicells and found that it induces filamentation. Further investigations showed that indolicidin inhibits DNA synthesis in E. colicells at concentrations at which RNA and protein synthesis are either partially affected or not affected at all. Since inhibition of DNA synthesis is also known to induce filamentation in E. coli, it appears to contribute to the antimicrobial activity of indolicidin.

We compared the structure and subunit composition of laminin in less tumorigenic mouse A9 and highly tumorigenic mouse A9HT cells by pulse-chase studies. During a 15' pulse, the ratio of laminin B1 to B2 subunits in cell lysates is 1:1 in both the A9 and A9HT cells; however, after a 3 hr chase, this ratio changes to 6:1 and 2:1 in the A9 and A9HT cells, respectively. Analysis of mature laminin subunits in culture media after a 3 hr chase also showed a similar higher ratio of B1 to B2 in the A9 cells as compared to the A9HT cells. The higher ratio of B1 to B2 subunits in A9 cells was evident as early as after a 30' pulse. A comparative analysis of steady-state levels of mRNAs for the laminin subunits B1 and B2 between A9 and A9HT cells showed a ratio of 1:1 for B and a ratio of 1:1.65 for B2. The ratio of B1 to B2 mRNAs in A9 cells was 1:1.3 whereas in A9HT cells it was 1:2.5, suggesting changes in the processing of mRNA in the highly tumorigenic A9HT cells. These observations suggest that the processing of laminin B subunits is altered during the process of increased tumorigenicity, thus resulting in the synthesis and secretion of structurally different laminin in tumorigenic A9HT cells as compared to the parent and less tumorigenic A9 cells.

A simple theory is presented which allows prediction of the rate of thinning of a viscous liquid film, initially coated upon a rigid plane surface, subjected to the action of an impinging jet. A set of experimental data provides confirmation of the theory. The removal of a thin film of liquid contaminant from a flat surface is often accomplished by flushing the surface with a jet of a second fluid. The rate of removal of the liquid contaminant is expected to be a function of the physical properties of the two fluids involved, the dynamic and geometric parameters that describe the impinging jet, and the topography of the surface itself. Although the impingement of a jet on clean, smooth, rigid surfaces has been well studied, (Giralt, et al. (1977), Scholtz and Trass (1970)) there has been almost no work done on the relatively more complex problem of jet impingement onto thin deformable surfaces. The present study focusses on the removal of a liquid spill (which is a deformable surface) from under an impinging air jet.

Soft-decision decoding is an NP-hard problem of great interest to developers of communication systems. We show that this problem is equivalent to the problem of optimizing Walsh polynomials. We present genetic algorithms for soft-decision decoding of binary linear block codes and compare the performance with various other decoding algorithms including the currently developed A* algorithm. Simulation results show that our algorithms achieve bit-error-probabilities as low as 0.00183 for a [104,52] code with a low signal-to-noise ratio of 2.5 dB, exploring only 22,400 codewords, whereas the search space contains 4.5 × 10l5codewords. We define a new crossover operator that exploits domain-specific information and compare it with uniform and two-point crossover.

Noxious cold sensation is commonly associated with peripheral neuropathies, however, there has been limited progress in understanding the mechanism of cold pain. Here we identify a role for kappa opioid receptors (KOR) in driving cold hypersensitivity. First, we show that systemic activation of KOR by U50,488 (U50), increases the latency to jump and the number of jumps on a cold plate at 3°C. KOR antagonist, NorBNI, attenuates U50-induced cold hypersensitivity. However, the central administration of NorBNI does not block U50-induced cold hypersensitivity suggesting that peripheral KORs may modulate this effect. To directly test this, we use the peripherally-restricted KOR agonist, ff(nle)r-NH2 and also show cold hypersensitivity. To begin to understand how peripheral KORs drive cold hypersensitivity we investigated whether KORs interact with transient receptor potential ankyrin 1(TRPA1) channels, known to facilitate the perception of noxious cold, in dorsal root ganglion (DRG). Using fluorescent in situ hybridization, we show that KOR mRNA colocalizes with the transcripts for the cold-activated TRPA1 channels in DRG. We also show a potentiation in intracellular calcium release in DRG during the simultaneous application of the TRPA1 agonist, mustard oil (MO), and a KOR agonist, U50, when compared to MO alone. Together our data suggest that peripheral KORs may induce cold hypersensitivity through modulation of TRPA1 channels.

The article offers information on the effect of the losses of hydrocarbon coabsorption on the revenues of gas plant. Topics discussed include the removal of mercaptans in acid gas removal unit (AGRU), the lifecycle costs and capital investment of the two process lineup such as aqueous amine and hybrid solvent, and the application of methyl diethanolamine (MDEA).

Introduction:The carotid web is a compelling potential mechanism of embolic ischemic stroke. In this study, we perform a systematic review and meta-analysis to determine the prevalence of ipsilesional carotid webs in patients with acute ischemic stroke.Methods:We performed a systematic review of prospective and retrospective observational studies enrolling consecutive patients with acute ischemic stroke. We included only studies in which high quality imaging of the cervical vessels was performed and in which the presence or absence of carotid web was adjudicated based on established criteria. The prevalence of carotid web was calculated in each study and pooled prevalence calculated via a random effects model. We also calculated relative risks of carotid web ipsilateral versus contralateral to stroke in the same pool of patients and performed sensitivity analyses including patients with cryptogenic stroke, patients less than 60 and patients with cryptogenic stroke <60.Results:A systematic review yielded 3,814 patients from 11 studies of whom 1,127 had cryptogenic stroke. We identified 4 studies in which we could derive data on patients <60 with cryptogenic stroke, a total of 332 patients. The relative risk of carotid web ipsilateral versus contralateral to ischemic stroke was 2.6 (95%: 1.6-4.3, p<0.01) in all patients with acute ischemic stroke and 3.0 (95% CI: 1.6-5.8, p<0.01) in patient less than 60 with cryptogenic stroke (Figure A-C). The pooled prevalence of ipsilateral carotid web in patients <60 with cryptogenic stroke was 13% (95% CI: 7%-22%; I2= 66.1%) (Figure D).Discussion:Carotid webs are more common in young patients with ESUS than in other stroke subtypes. Future studies concerning the diagnosis and secondary prevention of stroke associated with carotid web should focus on this population.

A spectroscopic study of the Ga–Hg excimer has been carried out for the first time. The vapor mixture excited by a RF discharge shows emission bands with an intensity maximum at 5020 Å. The density of Hg in this study was in the range of 1018–1019atoms/cc and that of Ga about 1011atoms/cc. High-resolution spectra with a dispersion of 1.2 Å/mm were obtained, and vibrational structures were resolved and analyzed on the basis of a triatomic species HgGa2.

Paraoxonase 1 variant IF-11 offers long-term prophylactic protection against chemical warfare nerve agents in mice.

Anthocephalus cadamba, an important plant in the traditional system of medicine in India, is reported to possess anticancer activity. Guided by bio-assay tests using human colorectal (HCT116) and hepatocellular carcinoma (HepG2) cell lines, it has been shown to contain three active constituents, the triterpenoid saponins 3-O-[α-L-rhamnopyranosyl]-quinovic acid (1)and 3-O-[α-L-rhamnopyranosyl]-quinovic acid 28-O-[β-D-glucopyranosyl] ester (2), and the alkaloid cadambine (3). The structures of the isolated compounds were established using spectroscopic techniques. The isolated compounds demonstrated concentration dependent inhibition of both the cell lines, where compound 3proved to be the most potent inhibitor of cell line HCT116 (IC5045 ± 4 μg/mL) and compound 2demonstrated maximum inhibitory activity against HepG2 cell line with an IC50value of 89 ± 7 μg/mL.

The feasibility of Ni supported Zr0.75Ce0.25O2-δ (ZCO) composites as steam methane reformable anode has been studied. ZCO powder was prepared by combustion synthesis technique using L-alanine as fuel. Phase pure material with average particle size below 1 µm was obtained upon calcination at 700oC for 6 h. Thermal expansion behaviour and electrical characterization of bulk samples of such Ni-ZCO composite anodes (Ni content between 20 and 40 vol%) have been carried out. Steam methane reforming (SMR) activity of the samples was also evaluated. The composite anodes were found to be quite promising in terms of matching thermal expansion coefficient, electrical conductivity and SMR activity. Anode supported single cells having configuration Ni-ZCO/YSZ/LSM have been fabricated and tested using methane as fuel.

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