Infrared spectroscopy of supported lipid monolayer, bilayer, and multibilayer membranes

A study was designed to determine the effects of triptorelin (Decapeptyl C.R.), a GnRH-agonist in a depot formulation, on androst-16-en-3-one (androstenone), LH, oestradiol and testosterone and on carcass composition and muscle structure in boars. Treatment with this highly potent GnRH analog ensured peptide release for 4 weeks when given to 18 animals at 135 days of age (group 1). Control animals (n = 20, group 2) received a saline injection. Blood samples (n = 10) were collected by venipuncture from each boar from 7 days before hormone treatment to 28 days after treatment. During the treatment period, three samples of back fat were taken by biopsy to determine the levels of androstenone and skatole. Testis size was determined at slaughter at 165 days of age. The treatment of boars with triptorelin increased concentrations of LH, oestradiol-17 beta, and testosterone for one day, followed by a decrease to base-line concentrations. The result of sensorial testing for boar taint detection at slaughter showed a slight reduction in this trait (0.76 vs. 0.99). The concentration of androstenone in the body fat of all treated animals was lower than the generally accepted limit of 0.5 microgram/g for the absence of boar taint, compared with the concentrations from 20 control animals among which 13 showed levels higher than this limit. The hormonal treatment significantly reduced the weight and size of the tests. There was no effect on skatole levels in backfat (0.141 vs. 0.150 microgram/g). The GnRH-agonist did not influence the carcass composition of treated boars. The muscle meat percentage was not significantly altered in the experimental group (51.39 vs. 50.50%). Overall, these results indicate that the use of this form of GnRH-agonist in a depot formulation offers a new possibility for reducing concentrations of androstenone which is mainly responsible for undesirable boar taint.     

单双层结构的石墨烯纳米带边界态的第一原理研究

利用基于密度泛函理论的第一性计算,对单双层结构的石墨烯纳米带的稳态结构和电子结构进行了研究。研究表明：α型的边界层的吸引使体系发生边界弯曲并存在非零能量边界态,届型的边界体系保持结构平整。它们都在单双层边界存在零能量的边界态。     

Assuring reliable performance of antibiotic assay media

The Microbiological Assay Branch of the National Center for Antibiotics Analysis assays over 100,000 samples of antibiotic products annually, using more than 1000 Ib dehydrated media. The media must be consistently dependable to produce accurate, reliable test results. To assure that the supply of media will meet the established requirements, each lot before purchase is subjected to a series of trials designed to examine growth support, sensitivity, and behavioral and physical factors. Actual antibiotic assays are conducted with the test medium, and performance is rated against a control medium. Controls on the system reduce the variables to allow appraisal of the medium itself.     

Cluster organization of ion channels formed by the antibiotic syringomycin E in bilayer lipid membranes

The cyclic lipodepsipeptide, syringomycin E, when incorporated into planar lipid bilayer membranes, forms two types of channels (small and large) that are different in conductance by a factor of sixfold. To discriminate between a cluster organization-type channel structure and other possible different structures for the two channel types, their ionic selectivity and pore size were determined. Pore size was assessed using water-soluble polymers. Ion selectivity was found to be essentially the same for both the small and large channels. Their reversal (zero current) potentials with the sign corresponding to anionic selectivity did not differ by more than 3 mV at a twofold electrolyte gradient across the bilayer. Reduction in the single-channel conductance induced by poly(ethylene glycol)s of different molecular weights demonstrated that the aqueous pore sizes of the small and large channels did not differ by more than 2% and were close to 1 nm. Based on their virtually identical selectivity and size, we conclude that large syringomycin E channels are clusters of small ones exhibiting synchronous opening and closing.     

New advances at the Nvokramatorsk Machine Plant in the technology and equipment used for straightening plates

The fruits of extensive research performed by the Novokramatorsk Machine Plant on plate-straightening and technical innovations developed by the plant in this area are allowing it to offer customers competitive roller-type straightening machines and new technologies suited for the precision straightening of a broad range of rolled products. The plate-straightening machines described in this article will be installed on the rebuilt TLS-2800 mill at the Alchevsk Metallurgical Combine by the end of 2006.     

Fluorescence assay for the detection of adherent Candida yeasts to target cells in microtest plates

We describe an assay based on photometric analysis for the measurement of adherence of Candida species to epithelial target cells (Vero cell line). Adherent Candida cells were detected by staining the cells with the fluorescent dye Calcofluor white (CFW), which binds to chitin and glucan in the yeasts. The tests were performed on microtest plates, which were analysed automatically by fluorescence plate readers. The assay is based on the following steps: (i) coating of the microtest plates with target cells (e.g. Vero cells); (ii) infection with Candida: (iii) staining of Candida with CFW; (iv) rinsing to remove non-adherent Candida cells and unbound dye; (v) detection of adherent fluorescent Candida cells. The test was able to detect 4 x 10(4) cells ml-1. The standard deviation was +/- 8%. Day-to-day variation was +/- 10% at most. The adherence of strains of different Candida species was assayed by a standard procedure. The results confirmed the order of adherence, with C. albicans ranking first, followed by C. tropicalis, C. parapsilosis and C. glabrata.     

Comparison of the Carpentier and Duran prosthetic rings used in mitral reconstruction

This clinical study was undertaken to evaluate the Duran flexible ring and the Carpentier rigid ring in terms of mitral annulus motion, transmitral flow and left ventricular function. Twenty-six patients (11 receiving rigid rings and 15, flexible rings) with normal sinus rhythm and with no or only trivial mitral valve regurgitation after surgical repair were selected. Angiograms demonstrated no significant differences in left ventricular systolic function between the two groups of patients. The area of the mitral annulus with the flexible ring significantly changed during the cardiac cycle. There were significant differences in the left ventricular fractional shortening (rigid ring, 35.8%; flexible ring, 43.4%) and in the peak velocity (rigid ring, 222 cm/s; flexible ring, 186 cm/s) at peak exercise. These data suggest that the flexible ring interferes less with the normal movements of the mitral annulus during the cardiac cycle, and that, under exercise conditions, it performs better than the rigid ring. We therefore conclude that mitral valve reconstruction using the Duran flexible ring is advantageous in patients with mitral regurgitation due to degenerative disease and sinus rhythm.     

Comparison of subperiosteal vs subgaleal elevation techniques used in forehead lifts

OBJECTIVE: To describe the occurrence and management of sexual dysfunction induced by selective serotonin-reuptake inhibitors (SSRIs), to provide an overview of sexual dysfunction, reports of SSRI-induced sexual dysfunction, and management strategies. DATA SOURCES: Information was retrieved from a MEDLINE English-literature search from January 1986 to July 1998 and by review of references. Indexing terms included sexual dysfunction, antidepressants, selective serotonergic reuptake inhibitors, fluoxetine, sertraline, paroxetine, fluvoxamine, clomipramine, buspirone, nefazodone, bupropion, cyproheptadine, amantadine, yohimbine, and central nervous system stimulants. STUDY SELECTION: There are no controlled studies describing SSRI-induced sexual dysfunction or its management. Twenty-one studies are presented, including 2 open-label studies, 12 case series, and 7 case reports. SSRI-induced sexual dysfunction is described with fluoxetine, paroxetine, sertraline, and fluvoxamine for 3-24 weeks of therapy. DATA SYNTHESIS: Data were organized according to the pharmacologic agent used in the management of SSRI dysfunction, target population, SSRI implicated, type of sexual dysfunction, experimental design, and treatment response. Data were extracted from methodology and results sections of reports. Methodologic flaws included failure to account for gender differences, omission of SSRI dose and duration, and use of concomitant drugs. CONCLUSIONS: The frequency of reports suggests that SSRI-induced dysfunction is a common adverse effect; controlled studies are necessary to determine prevalence. Most reports have occurred with fluoxetine, but this phenomenon may be related to its widespread use. Further study is needed to evaluate baseline sexual function, to define target populations, and to compare SSRIs in inducing sexual dysfunction. Serotonin antagonists and dopamine agonists have been used most often to treat SSRI-induced dysfunction and have generally been effective, but controlled studies are also needed.     

Development and introduction of a technology for making strip used for the support plates of copper-brass heat exchangers

The production of Kuprobreiz heat exchangers has been made more efficient by the introduction of a new technology at the Kirov Nonferrous Metals Plant for the production of 0.8–1.0 mm strip composed of new brass LN64-3.     

Comparison of PF4/heparin ELISA assay with the 14C-serotonin release assay in the diagnosis of heparin-induced thrombocytopenia

The diagnosis of heparin-induced thrombocytopenia (HIT) may be affirmed by demonstrating heparin-dependent anti-platelet antibodies using the 14C-serotonin release assay (SRA). In this study, results of the SRA was compared with the recently described platelet factor 4 (PF4)/heparin enzyme-linked immunosorbent assay (ELISA). Compared with the SRA, the sensitivity and specificity of a PF4/heparin ELISA was 87% and 92%, respectively, using an assay developed in our laboratory; and 90% and 98%, respectively, using a commercially developed kit (Diagnostica Stago, Asnieres, France). However, antibodies to PF4/heparin were also detected in up to 8% of patients whose plasma was negative by SRA, and 23% of patients receiving heparin who were not thrombocytopenic. These data indicate that results obtained with the PF4/heparin ELISA and the SRA are generally in accord in patients with a clinical diagnosis of HIT. However, discrepant results occur in approximately 20% of cases because of the greater sensitivity of ELISA and the possible involvement of other heparin-binding proteins. The fact that each assay contributes independent information in some cases must be considered in the sequence of test performance and in providing consultation to the practicing hematologist.     

Comparison of radioligand assay and immunostaining for epidermal growth factor receptor in human breast cancer

Epidermal growth factor (EGF) receptor status is a useful prognostic indicator in women with breast cancer. Lack of standardization and correlation of methodology for the detection of EGF receptor has hampered its further evaluation. EGF receptor status was ascertained by immunohistochemistry and radioligand assay in 120 breast cancers. Of 52 tumours negative for EGF receptor on radioligand assay, 47 were negative on immunohistochemistry and, of 68 tumours positive for the receptor on assay, 52 were positive on immunohistochemistry. If the more widely evaluated radioligand assay is assumed to be the 'gold standard', immunohistochemistry has a sensitivity of 81 per cent and a specificity of 91 per cent.     

Comparison of immunofiltration assay of plasma D-dimer with diagnostic imaging in deep vein thrombosis

This prospective study was designed to assess the diagnostic sensitivity, specificity and negative predictive value of the NycoCard D-dimer plasma immunofiltration assay in patients with suspected deep vein thrombosis (DVT) confirmed by ultrasonography/venography. 84 medical patients were recruited: 43 patients (51%) had proven venous thrombosis, 33 by venography and 10 by ultrasonography. The sensitivity of NycoCard D-dimer in patients with DVT was 95.3%, the specificity was 22.0% and the negative predictive value was 81.8%. An algorithm including the NycoCard D-dimer test for the acute management of DVT is proposed. This would enable low-risk patients to be discharged early from hospital, without imaging or anticoagulant therapy.     

Association between decreased susceptibility to a new antibiotic for treatment of human diseases, everninomicin (SCH 27899), and resistance to an antibiotic used for growth promotion in animals, avilamycin

Guinea-pigs were maintained for 5 weeks on a diet containing three different concentrations of vitamin C: a) traces (none added), b) medium (0.05% w/w) and high (0.5% w/w). Twenty-four hours before killing the animals received one i.p. dose of 3 g ethanol per kg body weight (a model of short-term acute intoxication). In a parallel experiment which lasted 5 weeks, the animals were treated every week with two i.p. doses of 1 g ethanol per kg body weight followed by the final acute intoxication (3g ethanol/kg) (a model of long-term chronic alcoholization). In both experiments, the guinea-pigs with the highest tissue concentration of vitamin C proved to have significantly decreased residual levels of ethanol and acetaldehyde in the liver and the brain, a decreased activity of alanine- and aspartate aminoacyl transferases in the serum and decreased contents of triacylglycerols and cholesterol in the serum and liver in comparison with the vitamin C-unsupplemented group. The regression curve expressing vitamin C levels versus residual ethanol and acetaldehyde concentrations in the liver confirmed the highly significant negative correlation between them. Administration of the guinea-pigs with large amounts of vitamin C appears to accelerate ethanol and acetaldehyde metabolism and reduce some of their adverse health effects.