Search

Background:Neuromedin U (NMU) is a neuropeptide with various physiological functions, including regulation of smooth-muscle contraction, blood pressure, stress responses and feeding behaviors. NMU activates two distinct receptors, NMUR1 and NMUR2, which are predominantly expressed in peripheral tissues and the central nervous system (CNS), respectively. It is reported that the NMU signaling system regulates food intake (FI) and body weight (BW) via NMUR2, suggesting that an NMUR2 agonist exhibiting anorectic effects would be a potential therapy for obesity.Methods:Antiobesity effects of NMUR2 activation were assessed using a recently developed, novel NMUR2-selective agonist, NMU-7005 (a polyethylene glycolated octapeptide). Here we assessed cumulative FI and BW loss after peripheral administration of NMU-7005 in NMUR2 knockout and diet-induced obese mice. To gain mechanistic insights, we performed immunohistochemical analysis of c-Fos-like protein expression in the brain.Results:We found that NMU-7005 was a NMUR2-selective agonist with little activity toward NMUR1. The anorectic effect of NMU-7005 was completely abrogated in NMUR2 knockout mice. Repeated subcutaneous administration of NMU-7005 showed a potent antiobesity effect with FI inhibition (P<0.025) in diet-induced obese mice. NMU-7005 in combination with the glucagon-like peptide-1 receptor (GLP-1R) agonist liraglutide showed an additive antiobesity effect, suggesting that NMUR2-mediated anorectic action is different from that of GLP-1R agonists. NMU-7005 also elicited a minimal conditioned taste-aversive effect, while the effect of liraglutide was significant. As c-Fos expression was upregulated in the hypothalamus and the medulla oblongata in NMU-7005-administered mice, the pharmacological effects of NMU-7005 appeared to be mediated via activation of the CNS.Conclusion:Our results demonstrated that a novel NMUR2-selective agonist, NMU-7005, is a beneficial tool for the elucidation of NMUR2-mediated physiological functions, which is a promising therapeutic strategy for treating obesity.

Capillary condensation from vapor has been studied at temperatures below the bulk melting point Tmof the condensing substance using a surface force apparatus. Both mica and mica modified by self-assembly of a fluorinated surfactant (perfluoro-1H,1H,2H,2H-decylpyridinium chloride) have been used as substrate surfaces. The condensing liquids, cyclooctane and menthol, nearly wet (contact angle <15°) mica but show a high (~60°) contact angle on the fluorinated surface. As in previous studies with unmodified mica, we find that both cyclooctane and menthol condense as liquids below Tm, and that the size of the condensates at solid-vapor coexistence is limited and inversely proportional to the temperature depression below Tm, or T. A comparison of the size of the condensates between the fluorocarbon surfaces and the mica surfaces and the quantitative dependence of the size of the condensate on Tfor cyclooctane lead us to conclude that the maximum condensate size is determined by the equilibrium between condensed, “supercooled” liquid and vapor, and is hence proportional to the surface tension of the liquid-vapor interface. From a consideration of the equilibrium between a liquid and a hypothetical solid condensate, it is concluded that a solid condensate does not usually form for kinetic reasons although two exceptions were found in earlier work.

The degree of micelle ionization of gemini surfactants has been investigated by using halide-sensitive fluorescence probes (e.g., 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ)). The fluorescence is quenched by the free bromide ions dissociated from surfactants. The degree of micelle ionization increased with increasing spacer chain length, but it decreased with increasing surfactant concentration. The Stern−Volmer plot gave two inflection points (i.e., not only at the cmc but also far above the cmc). The second inflection point suggested spherocylindrical micellar growth with decreases in the degree of micelle ionization. The spherocylindrical micellar growth was depressed with increasing spacer chain length, whereas it was enhanced with increasing tail chain length. The degree of micelle ionization of spherocylindrical micelles depended on the concentration and chain length of gemini surfactants. The change in SPQ fluorescence spectra upon hydrogenation was utilized to evaluate the solubilization site in micelle solutions. The dissolved SPQ in water was instantly reduced by the addition of NaBH4, resulting in abrupt changes in fluorescence intensity and spectral shift. All of the SPQ in micelle solution was also instantly reduced by NaBH4, indicating the existence of SPQ in the water bulk phase, but its fluorescence intensity increased upon the solubilization of hydrogenated SPQ into micelles.

A halide-sensitive fluorescence probe was utilized to evaluate the miscibility of fluorocarbon and hydrocarbon surfactants in aqueous micellar systems. The fluorescence of 6-methoxy-N-1,1,2,2-tetrahydroheptadecafluorodecylquinolinium chloride, FC10MQ, was quenched by halide ions dissociated from the surfactant. The fluorescence in micellar solutions showed an initially rapid decay. This suggests that halide ions effectively quench FC10MQ fluorescence at the micellar surface. The subsequent slow decay corresponds to the quenching of FC10MQ fluorescence in the aqueous bulk phase by the free counterions. The Stern−Volmer plots for fluorescence quenching gave a distinct break at the critical micelle concentration of the cationic surfactants. The abrupt increase in fluorescence quenching is attributed to the solubilization of the probe in the micelles. The fluorescence quenching behavior provides direct information about the immiscibility of fluorocarbon and hydrocarbon species in micelles, and the results indicate that almost pure fluorocarbon micelles appear in surfactants mixtures.

The compositions of the adsorbed aggregates at the mica−solution interface have been directly determined for mixtures of pyridinium chloride hydrocarbon and fluorocarbon surfactants by solution depletion measurements, including direct determination of the adsorbed layer composition for partially miscible surfactants. The measured adsorbed aggregate compositions are compared with predictions for bulk micelles using the group contribution method and regular solution theory. For fully miscible surfactants, there is good agreement between the models and experimental results. The group contribution method successfully predicts the existence of a miscibility gap for some mixtures, but adsorption experiments reveal some unusual features; the adsorbed layer consists of only one of the two coexisting micelle compositions, and its composition differs from that predicted. This effect is attributed to the substrate.

Abstract:  A 39-year-old woman with systemic lupus erythematosus (SLE) developed severe acute pancreatitis during a well-controlled disease stage. Treatment with intraarterial injections of antipancreatic enzyme and a small amount of prednisone (20 mg/day) led to remission of the pancreatitis. Disease activity of the SLE did not flare up throughout the course of this treatment. The development of severe acute pancreatitis in SLE is rare. We discuss the cause of pancreatitis in SLE, and whether corticosteroids may induce or improve pancreatitis.

Abstract A 39-year-old woman with systemic lupus erythematosus (SLE) developed severe acute pancreatitis during a well-controlled disease stage. Treatment with intraarterial injections of antipancreatic enzyme and a small amount of prednisone (20 mg/day) led to remission of the pancreatitis. Disease activity of the SLE did not flare up throughout the course of this treatment. The development of severe acute pancreatitis in SLE is rare. We discuss the cause of pancreatitis in SLE, and whether corticosteroids may induce or improve pancreatitis.

The adsorbed layer structure of tetradecylpyridinium, hexadecylpyridinium, heptadecafluorodecylpyridinium, and tetradecyltriethylammonium chloride and their mixtures on mica has been determined by AFM imaging. In addition, the composition of the mixed adsorbed layers has been measured, showing a significant surface enrichment of the pyridinium surfactants, particularly the partially fluorinated species. Shape transitions in the adsorbed layer are correlated with surface and bulk compositions and explained by consideration of the adsorption mechanism.

Abstract: The present paper describes the establishment of a method for simultaneous culturing of biliary epithelial cells (BECs) from the gall bladder (GB), extrahepatic bile duct (EBD) and intrahepatic bile duct (IBD) of the hamster. GB, EBD and IBD were cut from the biliary tree after collagenase perfusion of the liver. These biliary segments were minced into fragments. The fragments were embedded in collagen gel and cultured in Dulbecco’s modified Eagle medium / HamF12 medium containing 10% fetal bovine serum. The various cells subsequently spread from the fragments and formed cellular sheets. After the fragments and flattened cells were removed with the aid of a Pasteur pipette under phase-contrast microscopy, the sheets remaining were found to be composed of cuboidal cells. These cuboidal cells were shown to express gamma glutamyl transpeptidase and cytokeratin 7, which are known to be specific markers of BECs. Ultrastructurally, a large number of microvilli were observed on the luminal surface and junctional complex and interdigitation was identifiable on the lateral surfaces. BEC cultures were subcultured by digestion with collagenase and dispase and then dissociated by subsequent digestion in trypsin and ethylenediaminetetraacetic acid and then maintained on collagen gel for up to 8 weeks. After several passages, the BECs in culture eventually increased in size and showed vacuoles in the cytoplasm. They demonstrated irreversible growth arrest at 9 weeks. The BECs tended to form cystic structures when the BECs with collagen gel were transplanted into the interscapular fat pads of syngeneic hamsters. We established a method for culturing and transplanting biliary cells from syrian golden hamsters. This method may help to clarify the mechanism of hepatobiliary diseases.

The phase behavior of the cationic fluorocarbon surfactant 1,1,2,2-tetrahydroperfluorodecylpyridinium chloride in water has been studied using small-angle X-ray and ²H NMR spectroscopy as the main techniques. The following phase sequence was found:  micellar (L1), hexagonal (HI), centered rectangular (R; spacegroup c2mm) and centered trigonal (T, spacegroup R&thremacr;m) with increasing surfactant concentration. At higher concentrations evidence for random mesh phase and a lamellar phase was found, at high temperatures a bicontinuous cubic phase was found. Compared to a cationic hydrocarbon surfactant of similar hydrophobicity, the occurrence of the intermediate phases is more extensive in the phase diagram, and the fluorocarbon surfactant prefers to form intermediate phases instead of a cubic phase. The surface curvature of the aggregates changes from highly curved cylindrical structures of the hexagonal phase to the planar bilayer structure of the lamellar phase over a sequence of geometries that allow the average of the mean curvature to change gradually as water content is decreased.

Studies of the gas phase ion chemistry of triply charged metal ions, M³⁺ = Sc³⁺, Y³⁺, La³⁺, Ce³⁺, and Yb³⁺, were made by electrospray and laser spray. Triply charged ion ligand complexes, M³⁺(ligand)n were produced in the gas phase by electrospray and laser spray for the following ligands; glucose; sucrose; raffinose; cyclodextrin; ginsenoside Rb1; dimethyl sulfoxide (DMSO) and hexamethylphosphoramide (HMPA). The ion evaporation mechanism must be invoked to explain the transfer of more surface active ions (e.g., NH4⁺(H2O)n) in solution to the gas phase, while the transfer of low surface active ions (e.g., La³⁺(sucrose)n) may be explained by the charged residue model. In general, the laser spray gives stronger ion signals than electrospray for aqueous and water/methanol solutions. The laser spray is found to be more suitable for the observation of ions with larger solvation energies (e.g., Sc³⁺(DMSO)n). These results may be due to the enrichment of the sample concentration by the selective vaporization of the volatile solvent on the tip of the stainless steel capillary and also to the finer droplet formation caused by the laser irradiation. Copyright © 1999 John Wiley & Sons, Ltd.

The behavior of fluorocarbon and hydrocarbon quenchers toward pyrene fluorescence was informative as to not only the distribution of quenchers among micelles but also the microscopic micelle demixing. The slight differences of quenching extent between fluorocarbon and hydrocarbon quenchers were observed to come from the deviation from Poisson distribution of fluorocarbon quenchers among hydrocarbon micelles. The intermicellar statistical distribution of quenchers could be influenced by the low affinity between fluorocarbon and hydrocarbon chains. The lost quenching of pyrene was observed due to the separated solubilization of pyrene and fluorocarbon quencher into two types of mixed micelles. However, the differences of quenching extent between fluorocarbon and hydrocarbon quenchers became small for sodium perfluorooctanoate−dodecyl sulfate mixtures at high concentration and temperature. The mutual miscibility in a micelle increased due to the increase of the micelle size under high surfactant concentrations and the heat of mixing at high temperature. The pyrene fluorescence quenching method using fluorocarbon quencher was effective way to indicate the demicellization phenomenon.

Cyclic voltammetry of (ferrocenylmethyl)trimethylammonium bromide (FcTAB) was applied on anionic micelle systems in order to reveal the solution properties of micelles composed of fluorocarbon surfactants. Diffusion coefficients of FcTAB decreased with micelle formation because the cationic FcTAB diffuses together with micelles. The diffusion coefficient abruptly decreased with the addition of sufficient salt, suggesting an increase in micelle size and a transition of micelle shape. The diffusion coefficient for mixed micelles composed of fluorocarbon and hydrocarbon surfactants decreased considerably compared to those for their single surfactant systems. The micelle size of fluorocarbon surfactants, especially for lithium 1,1,2,2-tetrahydroheptadecafluorodecyl sulfate, significantly depended on the salt concentrations and the compositions of the mixtures. Cyclic voltammetry is a simple and useful method to evaluate the micelle diffusion coefficients of fluorocarbon surfactants which can hardly be estimated by dynamic-light-scattering measurements.

Studies of the gas phase ion chemistry of triply charged metal ions, M3+= Sc3+, Y3+, La3+, Ce3+, and Yb3+, were made by electrospray and laser spray. Triply charged ion ligand complexes, M3+(ligand)nwere produced in the gas phase by electrospray and laser spray for the following ligands; glucose; sucrose; raffinose; cyclodextrin; ginsenoside Rb1; dimethyl sulfoxide (DMSO) and hexamethylphosphoramide (HMPA). The ion evaporation mechanism must be invoked to explain the transfer of more surface active ions (e.g., NH4+(H2O)n) in solution to the gas phase, while the transfer of low surface active ions (e.g., La3+(sucrose)n) may be explained by the charged residue model. In general, the laser spray gives stronger ion signals than electrospray for aqueous and water/methanol solutions. The laser spray is found to be more suitable for the observation of ions with larger solvation energies (e.g., Sc3+(DMSO)n). These results may be due to the enrichment of the sample concentration by the selective vaporization of the volatile solvent on the tip of the stainless steel capillary and also to the finer droplet formation caused by the laser irradiation. Copyright © 1999 John Wiley & Sons, Ltd.

Background:To investigate the efficacy of thin-section oblique axial magnetic resonance (MR) images in evaluating cervical invasion by endometrial carcinoma. Methods:Sixty-seven patients with endometrial carcinoma were evaluated with pathologic correlation. We compared the accuracy in the assessment of cervical invasion by endometrial carcinoma between parasagittal MR images and thin-section oblique axial MR images by using T2-weighted and contrast-enhanced T1-weighted pulse sequences. Results:Cervical invasion by endometrial carcinoma was confirmed by pathologic examination. Cervical invasion was seen in 16 patients. The accuracy rates of parasagittal T2-weighted images, thin-section oblique axial T2-weighted images, parasagittal contrast-enhanced T1-weighted images, and thin-section oblique axial contrast-enhanced T1-weighted images were 74.7%, 89.5%, 82.0%, and 95.5%, respectively. Statistically significant differences were seen between parasagittal T2-weighted images and thin-section oblique axial T2-weighted images (p= 0.002) and between parasagittal contrast-enhanced T1-weighted images and thin-section oblique axial contrast-enhanced T1-weighted images (p= 0.003). Conclusion:Thin-section oblique axial MR images are considered to be useful for the assessment of cervical invasion by endometrial carcinoma.

Background:To investigate the efficacy of thin-section oblique axial T2-weighted images in the assessment of parametrial invasion by cervical carcinoma. Methods:One hundred parametria of 50 patients with cervical carcinoma were evaluated with pathologic correlation. We compared the sensitivity, specificity, and diagnostic accuracy in the assessment of parametrial invasion by cervical carcinoma between axial T2-weighted images and thin-section oblique axial T2-weighted images. Results:Thin-section oblique axial T2-weighted images provided accurate cross sections of the cervix with excellent detail and detected parametrial invasion more accurately than did axial T2-weighted images showing cross sections of the trunk. Although the sensitivity, specificity, and accuracy for parametrial invasion were 46.4%, 91.7%, and 79.0%, respectively, on axial T2-weighted images, the corresponding values were 67.9%, 97.2%, and 89.0%, respectively, on thin-section oblique axial T2-weighted images. There were statistically significant differences in the sensitivity (p = 0.014),specificity (p = 0.046),and accuracy (p = 0.002)in detecting parametrial invasion between these two types of images. Conclusions:Thin-section oblique axial T2-weighted images are useful for the assessment of parametrial invasion by cervical carcinoma.

Background:The purpose of this multi-institutional study was to examine the appearance of struma ovarii on magnetic resonance (MR) images. Methods:MR images of 12 patients with histologically proven struma ovarii were retrospectively reviewed. All patients underwent T1-weighted and T2-weighted imaging. Contrast-enhanced T1-weighted images with Gd-DTPA were available in 10 patients. The following determinations were made: tumor morphology, signal intensities, contrast-enhancement effects of solid components with Gd-DTPA, and comparison of MR images with resected specimens. Results:All 12 patients had both cystic and solid components, with a multilobulated surface and thickened septa. Signal intensities on T1-weighted images were mainly low, partly intermediate to high, or high, and those on T2-weighted images were mainly high, with different signal intensities. Contrast-enhancement effects were marked or moderate. The contents that showed low signal intensities on T1-weighted images and signal voids or low signal intensities on T2-weighted images were viscid gelatinous materials. Conclusions:A multicystic tumor with a solid component, a multilobulated surface, and signal intensities that indicate the presence of viscid gelatinous materials appear to be a characteristic MR finding of struma ovarii.

The aggregation behavior of the cationic fluorocarbon surfactants 1,1,2,2-tetrahydroperfluoroalkylpyridinium chloride and 2-hydroxy-1,1,2,3,3-pentahydroperfluoroalkyldiethylammonium chloride in aqueous solution have been studied using cryo-transmission electron microscopy as the main technique. The effects on aggregate structure of factors such as surfactant and salt concentration, counterion type, and alkyl chain length were investigated. Similar to hydrocarbon surfactants the fluorocarbon surfactants self-assemble into various aggregates such as micelles, threadlike micelles, vesicles, and other lamellar aggregates. A distinctive property of the fluorocarbon surfactants is their tendency to form structures with little curvature, such as cylindrical micelles and bilayer structures. Even a very small reduction of the repulsion between the headgroups is sufficient to accomplish a sphere to rod transition, so that a solution of globular micelles in water is turned into a highly viscous, sometimes viscoelastic solution on the addition of low concentrations of a simple salt. The differences between the fluorocarbon and hydrocarbon surfactants are discussed.

The automated test system for computer-controlled low-cycle fatigue crack growth can be achieved using multi-task programming. The results of constant ΔJtest show the degree of success achieved with this system. This automated system integrates the ΔJrange in real time and controls it. It was shown that task priorities in the multi-task system gave great efficiency in developing the automated elastic-plastic fatigue crack growth system. The test system described herein was used to produce results of the constant ΔJtest for the material of JIS SM41B. The crack growth rates remained constant for many constant ΔJtests as expected. This shows the effectiveness of the developed system. In these elastic-plastic crack growth rate experiments, the property of the closure load was also analyzed and was shown to be always compressive and to be a function of both the magnitude of ΔJand crack length. An availability of such precise analysis for crack closure behavior is also a great advantage of using a multi-task system.

This study shows how trace amounts of surfactants are adsorbed by activated carbon under competitive conditions in aqueous solution. Surfactants used as adsorbates are sodium dodecyl sulfate (SDS) and eicosaneoxyethylene hexadecyl ether (POE). Activated carbon used as an adsorbent is Pittsburgh activated carbon. Adsorption isotherms on the activated carbon were all Freundlich-type, both in the multi-solute system and in the mono-solute systems. The total adsorbed amount in the multi-solute system increases linearly with increasing molar fraction of SDS in the initial concentration. Thus, the total adsorbed amount in the multi-solute system can be estimated by the Freundlich constants, which can be determined from the single-solute equilibrium adsorptions, and molar fractions of adsorbates in the initial concentration.

Optical rotation and laser diffraction measurements were made on cholesteric solutions of a triple helical polysaccharaide schizophyllan. It was found that optical rotation Θ and cholesteric pitch P changed abruptly at about 7°C when the temperature was changed. These abrupt changes in Θ and P were accompanied by a small but distinct endothermic peak on a DSC thermogram. It was concluded that the cholesteric phase of aqueous schizophyllan underwent a thermal structure transition just above its freezing point, which probably proceeded in two stages: a change in solvation of schizophyllan triple helices followed by re-orientation of the solvated helices.

Electromigration experiments of ionic surfactants were performed by using a capillary tube isotachophoretic apparatus. The zone of the migrated surfactant was collected after separation, and the surfactant concentration of the migrated zone was determined by HPLC analysis. The surfactant concentration of the migrated zone was increased with an increase in electrolyte concentration, and was in accord with the prediction of the Kohlrausch equation. When the electrolyte concentration further increased, the surfactant molecules began to migrate as a micellar state. Moreover, the mixed systems of ionic-non ionic and ionic-ionic surfactants were also examined and revealed the migration as mixed micelle.

Microviscosity, micellar aggregation number, and the critical micelle concentration (cmc) of potassium N-acylalaninates were determined in KCl solutions by fluorescence probe methods together with their solution viscosity. Two inflection points were observed on the plot of microviscosity vs KCl concentration. The first and second inflection points were attributed to the beginning of micellar growth and intermicellar interaction, respectively. At a KCl concentration above the first inflection point, the micellar aggregation number steeply increased and the log−log plot of cmc against KCl concentration deviated downward from a linear Corrin−Harkins relation. Above the second inflection point, the micellar solutions of N-acylalaninates became very viscous and exhibited a constant microviscosity. Comparison with the previous data for N-acylvalinates (Langmuir 1995, 11, 2951) revealed that microviscosity on the micellar surface was larger in N-acylalaninates than in N-acylvalinates, while microviscosity in the micellar core was the same in the two surfactant series. Each N-acylalaninate solution was divided into four regions (solution of monomer surfactant, region of globular micelles, region comprising large micelles followed by micellar growth, and region where there is strong intermicellar interaction). Each boundary between the regions shifted to lower concentrations of KCl and N-acylalaninate as the acyl chain became long.

A new cationic surfactant, 1,1,2,2-tetrahydroheptadecafluorodecylpyridinium chloride (HFDePC), quenches the fluorescence emission from pyrene in pure micelles but hardly quenches it in mixed micelles composed of fluorocarbon and hydrocarbon surfactants. Pyrene is located in hydrocarbon-rich micelles, and its fluorescence is quenched by cetylpyridinium chloride. However, HFDePC is mainly solubilized in fluorocarbon-rich micelles, and a collision probability between pyrene and HFDePC would be small within the lifetime of the excited pyrene. That is, the depression of quenching by HFDePC could be ascribed to the coexistence of two kinds of mixed micelles. The effects of addition of salt and temperature toward the depression of quenching were also examined.

The plug calorimeter of the Collider Detector at Fermilab (CDF) [1] will be upgraded, replacing the existing gas calorimeter by a scintillating tile/fiber calorimeter. We have completed R&D for the CDF plug upgrade EM calorimeter. We describe the results of the R&D leading to the final design of the tile/fiber system for the calorimeter. Kuraray SCSN38, Kuraray Y11 and PET film (E65) were chosen as materials for scintillating tiles, wavelength shifting (WLS) fibers and a surface reflector on tiles, respectively, in view of obtaining large light yield and uniform response from a tile/fiber system. We decided fiber groove path in a tile, groove cross-sectional shape and groove depth for each tile to get uniform response from a tile/fiber. For the tile/fiber system of the final design, the average light yield was larger than 3.0 photoelectrons per minimum ionizing particle (MIP), the response uniformity in a tile was less than 2.5% and a total cross talk from a tile to the adjacent tiles was less than 2.0%. These results satisfied our requirements.

Fluorescence-quenching of pyrene in micellar system has been investigated using 1,1,2,2-tetrahydroheptadecafluorodecylpyridinium chloride (HFDePC). The new fluorocarbon quencher has a similar quenching ability as hexadecylpyridinium chloride (CPC) towards pyrene in hydrocarbon micelles if only a quencher molecule is solubilized in a micelle. The fluorocarbon quencher randomly distributed among micelles if the average occupancy number of probes per a micelle was small enough. The fluorescence behavior of pyrene was examined for hexadecyltrimethylammonium chloride (CTAC) and HFDePC mixtures. The variation of fluorescence intensity gave second cmc, reflecting the micellar immiscibility of fluorocarbon and hydrocarbon surfactants. The second cmc can be simulated by material balances of both surfactants supposing the coexistence of two kinds of mixed micelles. The fluorescence-quenching behavior suggested the enhanced micellar immiscibility probably due to nonrandom distribution of fluorocarbon quenchers among micelles.

We have obtained direct evidence that shows the cellular formation and subsequent release of a potent inhibitor (feedback regulator) of adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] by adipocytes, upon stimulation with epinephrine. The appearance of such a feedback regulator in adipocytes preceded its release into the medium. During a 30 min incubation, intracellular regulator levels rose rapidly and reached 39-61 units/g of adipocyte at 10 min. Release of inhibitor into the medium increased slowly and was 11-16 units/g of adipocyte at 10 min. Upon continued incubation, the cells at 30 min contained 30-41 units/g of ingibitor, slightly less than the content at 30 min; meanwhile, the medium content rose more than 3-fold. The inhibitor from both locations appeared to have the same characteristics, judging from the purification procedures and the biological activities on hormone-stimulated adenylate cyclase. Adenylate cyclase was inhibited by the feedback regulator in vitro when either epinephrine, corticotropin (ACTH), or glucagon was used as activator. The site of action of this inhibitor is therefore most likely beyond the specific hormone receptors. A new in vitro action of insulin has been found. Insulin, 50-500 microunits/ml, inhibited the formation and release of this factor from isolated rat or hamster adipocytes by 29-81% after these cells were stimulated by hormones that raise intracellular adenosine 3':5'-cyclic monophosphate. This factor enhaced the effect of insulin in lowering the adenosine 3':5'-cyclic monophosphate levels in fresh rat adipocytes. A reduced formation of such a factor may modify the metabolic events in adipocytes, and some as yet unexplained effects of insulin could therefore be linked to the metabolic effects of this factor.

It is generally recognised that the flux type of covered electrodes affects the profile and mechanical properties of welds and may well control the fatigue strength of fillet welded joints. Fillet welded joints, however, have seen few systematic investigations. The purpose of this investigation is to improve the fatigue strength of fillet welded joints through appropriate design of the covered electrode flux.Ten types of covered electrode were trial-manufactured with variation in the flux system at two levels (to improve the profile of the fillet toe region) and the added alloying element contents of each system at five levels (to vary the hardness of the weld metal). These covered electrodes were used to prepare non-load-carrying cruciform fillet welded joints using 570 MPa class high-strength steel base metal. Fatigue tests (S = σmax - σmin, σmax = σY) were run with the fillet welded joints. The results obtained may be summarised as follows: The profile of the fillet welds appears to be affected by the flux system and base metal but not by the added alloying elements. The maximum stress concentration factor (Kmax) is reduced to Kmax ⌣ 1.59 for covered electrodes using an MgCO3-MgO-CaF2-iron powder system flux (M' series). The fatigue strength of the fillet welded joints at 2 × 106 cycles is improved to around 143 MPa in the M' series. It can safely be said that there is an inverse correlation between Kmax in the toe region and the fatigue strength of the welded joints. Appropriate relations are developed and used to calculate the recovery to the weld metal of added alloying elements. The recovery to the weld metal of the added alloying elements on average gives minima of around 98%Ni, 94%Mo, 85%Cr (which are good), and around 11%B.

Cu/ZrO2 was highly active and selective for the title reaction. The activity obtained exceeded greatly that obtained over Cu/SiO2. It was shown that the precursors highly dispersed on zirconia support were readily reduced to very fine particles of metallic copper.

The chromosomal normality of rabbit oocytes fertilized in vitro was examined. Ovum donors were superovulated with pregnant mare’s serum gonadotropin and human chorionic gonadotropin (hCG). Follicular oocytes were collected laparoscopically 9–10 h after hCG treatment and incubated in vitro with spermatozoa capacitated in vivo.Of 267 aspirated oocytes, 191 (71.4%) were fertilized in vitro and developed to the 2- to 8-cell stage 24–48 h after insemination. In the chromosomal studies, 121 (63.4%) were examined. Of these, 94 (77.7%) had a normal diploid complement of chromosomes (2n = 44) and 6 (5%) showed aneuploidy. Of the remaining 21, 20 were triploid and one was tetraploid. The incidence of triploid oocytes after in vitro fertilization was higher than the rate in vivo (16.5% vs. 9.0%, respectively). These triploid oocytes were suspected to be the result of polyspermic fertilization in vitro. In addition, at the Metaphase II stage, 62 (89.9%) of 69 induced, preovulatory oocytes had a normal number of chromosomes.

The in vitro maturation sequence of squirrel monkey oocytes and their chromosomal normality was studied. Follicular growth was induced by a hormonal regimen of follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) and oocytes were collected laparoscopically 15–16 h after hCG administration from 55 squirrel monkeys. A total of 666 oocytes were prepared and analyzed for maturational stage and the presence of chromosomal aberrations.At recovery, 84.7% of the aspirated oocytes were in the genninal vesicle or prophase I stage and the numbers of atretic and mature ova were low (15.3% and 8.3%, respectively). The highest rate of in vitro matured oocytes (75.2%) was found after 31 h of incubation.In the chromosomal analysis studies of 366 oocytes, 31(8.5%) metaphase 1, 14 (3.8%) anaphase I and 181 (49.5%) metaphase II oocytes were examined. Of 28 countable metaphase I plates, 21 (75.0%) consisted of 22 bivalents, however meiotic univalents were also observed in 7 (25.0%) cases. Of these, 2 showed a secondary association.Of 181 oocytes, 145 (80.1%) were analyzable numerically. Of these, 88 (60.7%) had the normal haploid 22 chromosome number, whereas 7 (4.8%) showed aneuploidy (4 hyperploidy and 3 hypoploidy). An additional 50 (34.5%) oocytes were found to be at the metaphase II stage with first polar body chromosomes. Of these, 43 had a normal haploid number of chromosomes (22/22). In 7 (4.8%), aneuploidy was observed (6, 21/23 and 1, 20/24). The unequal chromosome number was assumed to be due to a random segregation of univalents at the anaphase I stage.Additionally there was no significant difference in maturation rate among 3 sizes of follicles (1–2 mm, 2–3 mm, >3 mm). A significant correlation was found for the maturation rate between oocytes with and without cumulus cells after 21 h of culture.

The effect of 1 µM dibutyril cAMP (cAMP media) on the chromosomal normality of in vitro fertilized squirrel monkey oocytes was examined. A total of 877 oocytes were collected laparoscopically 15–16 h after hCG injection from hormonally-induced follicles of 65 squirrel monkeys. Of these, 330 (37.6%) were prepared between 6 and 30 h after insemination and analyzed. Sperm penetration and the presence of a swollen sperm head in the ooplasm were observed by 6 h, and the nucleate stage by 10 h. Addition of 1 µM dbcAMP did not affect the oocyte maturation rate, however the in vitro fertilization rate was increased 26.5% over controls (46.3 vs. 36.6%).The first cleavage metaphase was found at 16 h after insemination. Between 24 and 30 h post-insemination, 76.6% of fertilized oocytes had reached the first cleavage metaphase. An incidence of triploidy (including dispermy) of 11.7% was observed.After chromosomal analysis of metaphase I, univalents were observed in 16.7% of the cases. Aneuploidy (8.9%) was also found in metaphase II. Of the first cleavage metaphases, 88.0% had the diploid number of chromosomes. Aneuploidy occurred 12.0% of the time and 5 cases of triploidies were observed.

Time-resolved fluorescence quenching studies of nonionic, anionic, and cationic micelles have been performed to compare two surfactant quenchers, a fluorocarbon surfactant quencher, N-(1,1,2,2-tetrahydroperfluorodecanyl)pyridinium chloride (HFDePC) and a hydrocarbon quencher of similar hydrophobicity, C16PC, N-hexadecylpyridinium chloride. The concentration dependence of the apparent aggregation numbers informs on the interaction between the surfactants, which always was repulsive for the fluorocarbon quencher in hydrocarbon micelles, except for the case with a nonionic micelle, where the effectively attractive electrostatic interaction dominated at low ionic strength. The simple theory (Almgren, M.; Hansson, P.; Wang, K. Langmuir 1996, 12, 3855) suggests that the interaction parameter from the slope of the apparent aggregation number versus mole fraction quencher should be the same as the interaction parameter describing the change of the critical micelle concentration with composition according to regular solution theory (Rubingh, D. H. In Solution Chemistry of Surfactants; Mittal, K. L., Ed.; Plenum Press:  New York, 1979; Vol. 1, p 337). The results show that it is not so; not even the sign of the interaction parameter is always the same. The reasons for the difference are discussed. For the weight average aggregation number, obtained by extrapolation to zero quencher concentration, the two quenchers gave results within about 10% for a given surfactant; the values with the fluorocarbon quencher seemed to be systematically lower, as if the aromatic probe strongly avoided micelles containing fluorocarbon quenchers. From solubility studies, pyrene was found to prefer a C16TAC micelle over a HFDePC micelle by a factor of 60. The preference of pyrene for micelles without fluorocarbon surfactants was utilized to show the demixing into fluorocarbon-rich and hydrocarbon-rich micelles in a mixture of lithium perfluorononanoate and lithium dodecyl sulfate and in cetyltrimethylammonium chloride and HFDePC.

We examined the immiscibility of fluorocarbon and hydrocarbon surfactants having the same head groups, i.e., lithium 1,1,2,2-tetrahydroheptadecafluorodecyl sulfate (LiHFDeS) and lithium tetradecyl sulfate (LiTS). The micellar pseudophase diagram was determined by conductivity and fluorescence quenching methods. The coexistence of two kinds of micelles has been demonstrated by the fluorescence quenching of pyrene with a fluorocarbon quencher. Pyrene is located in LiTS-rich micelles, and its fluorescence is quenched by micelle-solubilized quenchers. However, the pyrene fluorescence is hardly quenched by a fluorocarbon quencher when a second type of micelle rich in fluorocarbon surfactant appears. The collision probability between the fluorocarbon quencher and pyrene will be small within the lifetime of the excited pyrene because the fluorocarbon quencher and pyrene are separately solubilized in LiTS-rich and LiHFDeS micelles, respectively. The effect of addition of salt on the depression of quenching was also examined.

Ultrasonic cavitation of polyethylene single crystals and single-crystal aggregates in the form of cakes results in lamella fragmentation and necking involving the transformation of lamellar crystals into fibrillar crystals between 20 to 400 Å in diameter. The smaller fibrils (∼20-30 Å) have a very smooth appearance, whereas the larger ones (∼100-400 Å) contain a beady structure about 100 Å periodically spaced along the fibrils. The smoother microfibrils are suggested to contain extended chains that are formed by unfolding of molecules directly from the chain-folded lamellae as well as from the folded-chain crystals contained within the beady fibrils. The presence of the chain-folded crystals within the larger beady fibrils is shown in numerous instances to be due to incorporation of mosaic crystalline blocks originally present, but weakly connected to one another, in the lamellar single crystals. The necking process is deduced by observation to involve primarily a mechanical shearing of mosaic crystalline blocks along the c-axis plus a rotation into the fibril direction. Observation of extreme resistance of lamellae in the overgrowth regions to cavitation damage suggests the presence of tie molecules and/or interpenetrating cilia between these lamellae. The suggestion finds strong support from additional studies carried out on lamellae that have been tied together at the folds by cross-linking with γ rays.

Hydrogenated microcrystalline germanium (μc-Ge : H) films have been grown on crystalline (c-) Si and Ge substrates in a temperature range from 25 to 313 °C, by means of electron-cyclotron-resonance plasma chemical vapor deposition. An increase in substrate temperature induced an amorphous to microcrystalline phase transition at around 50 °C, and increased the crystalline volume fraction of μc-Ge : H on both c-Si and c-Ge. A volume fraction of nearly 100% was realized at 200 °C. Above this, (1 0 0) preferential growth of μc-Ge : H was observed on both c-Si(1 0 0) and c-Ge(1 0 0). For c-Si(1 1 1) and c-Ge(1 1 1) substrates, the growth direction was mainly (1 1 1), but containing (1 1 0) and (3 1 1) components, attributed to twin formation. The dependence of the film-surface roughness on the substrate temperature was also examined. The peak energy and magnitude of the photoluminescence decreased with increasing substrate temperature.

A mixed surfactant approach has been successfully employed in an aerosol-based synthesis of spherical silica particles exhibiting a new core–shell structure where the shell and the core exhibit different ordered mesoporosity and pore sizes.

A mixed surfactant approach has been successfully employed in an aerosol-based synthesis of spherical silica particles exhibiting a new core–shell structure where the shell and the core exhibit different ordered mesoporosity and pore sizes.