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31.
Alexandr Parlesak Michael Hans-Ulrich Billinger Christian Sch?fer Heinz-Dieter Wehner Christiane Bode Johann Christian Bode 《Alcohol》2004,34(2-3):121-125
Intravenous infusion of fructose has been shown to enhance reduced form of nicotinamide adenine dinucleotide reoxidation and, thereby, to enhance the metabolism of ethanol. In the current study, the effect of fructose infusion on first-pass metabolism of ethanol was studied in human volunteers. A significantly higher first-pass metabolism of ethanol was obtained after administration of fructose in comparison with findings for control experiments with an equimolar dose of glucose. Because fructose is metabolized predominantly in the liver and can be presumed to have virtually no effects in the stomach, results of the current study support the assumption that only a negligible part of first-pass metabolism of ethanol occurs in the stomach. 相似文献
32.
Krupitsky EM Zvartau EE Masalov DV Tsoi MV Burakov AM Egorova VY Didenko TY Romanova TN Ivanova EB Bespalov AY Verbitskaya EV Neznanov NG Grinenko AY O'Brien CP Woody GE 《Journal of substance abuse treatment》2004,26(4):285-294
Naltrexone may be more effective for treating opioid (heroin) dependence in Russia than in the U.S. because patients are mostly young and living with their parents, who can control medication compliance. In this pilot study we randomized 52 consenting patients who completed detoxification in St. Petersburg to a double blind, 6-month course of biweekly drug counseling and naltrexone, or counseling and placebo naltrexone. Significant differences in retention and relapse favoring naltrexone were seen beginning at 1 month and continuing throughout the study. At the end of 6 months, 12 of the 27 naltrexone patients (44.4%) remained in treatment and had not relapsed as compared to 4 of 25 placebo patients (16%; p<0.05). Since heroin dependence is the main way HIV is being spread in Russia, naltrexone is likely to improve treatment outcome and help reduce the spread of HIV if it can be made more widely available. 相似文献
33.
Quantitative analysis of human immunoregulatory cytokines by electrochemiluminescence method 总被引:3,自引:0,他引:3
Sennikov SV Krysov SV Injelevskaya TV Silkov AN Grishina LV Kozlov VA 《Journal of immunological methods》2003,275(1-2):81-88
Quantitative analysis of human immunoregulatory cytokines in physiological media and cell cultures plays an important role in fundamental and clinical research. Here we describe the quantification of interleukin (IL)-2, IL-4, IL-10 and interferon-gamma (IFN-gamma) in human serum and peripheral blood mononuclear cell (PBMC)-conditioned medium by electrochemiluminescence method (ECL). We demonstrate that this approach allows to detect cytokine concentration from 1 pg/ml. The high sensitivity in combination with accuracy and wide range of determined concentration indicates that ECL meets the standards of quantitative analysis of cytokines. Simplicity and short time of procedure, small assay volume and high reproducibility make ECL method competitive in practical use with conventional quantitative methods of cytokine detection. 相似文献
34.
Antonov AS Afiyatullov SSh Kalinovsky AI Ponomarenko LP Dmitrenok PS Aminin DL Agafonova IG Stonik VA 《Journal of natural products》2003,66(8):1082-1088
New steroidal oligoglycosides mycalosides B-I (2-9) have been isolated from the polar extract of the Caribbean sponge Mycale laxissima, and their structures have been elucidated by 1D and 2D NMR ((1)H, (13)C, DEPT, COSY-45, COSY-RCT, HSQC, HMBC, and NOESY spectra) and MALDI-TOF mass spectrometry. Mycalosides B (2) and C (3) were shown to be 27- and 28-nor derivatives of the previously known tetraoside mycaloside A (1). Mycaloside D (4) differs from 1 only in the presence of an additional acetyl group in the carbohydrate moiety. Mycaloside E (5) was structurally identified as a 28-nor-4-dehydroxy derivative of 1. Mycalosides F-H (6-8), differing from each other by the structures of their side chains and nonacetylated (7, 8) or acetylated (6) tetrasaccharide carbohydrate moieties, have new 5(6)-unsaturated 3 beta,4 beta,21-trihydroxy-15-keto-steroidal aglycons. Mycaloside I (9) is a tetraoside of a new 7,24(28)-diunsaturated 3beta,15 beta,29-trihydroxystigmastane aglycon. It was established that the total fraction of the mycalosides as well as mycalosides A (1) and G (7) inhibit the fertilization of eggs by sperm of the sea urchin Strongylocentrotus nudus preincubated with these compounds. 相似文献
35.
36.
Glial fibrillary acidic protein (GFAP) is the main component of intermediate filaments in astrocytes. To assess its function in astrocyte swelling, we compared astrocyte membrane properties and swelling in spinal cord slices of 8- to 10-day-old wild-type control (GFAP(+/+)) and GFAP-knockout (GFAP(-/-)) mice. Membrane currents and K(+) accumulation around astrocytes after a depolarizing pulse were studied using the whole-cell patch-clamp technique. In vivo cell swelling was studied in the cortex during spreading depression (SD) in 3 to 6-month-old animals. Swelling-induced changes of the extracellular space (ECS) diffusion parameters, i.e., volume fraction alpha and tortuosity lambda, were studied by the real-time iontophoretic tetramethylammonium (TMA(+)) method using TMA(+)-selective microelectrodes. Morphological analysis using confocal microscopy and quantification of xy intensity profiles in a confocal plane revealed a lower density of processes in GFAP(-/-) astrocytes than in GFAP(+/+) astrocytes. K(+) accumulation evoked by membrane depolarization was lower in the vicinity of GFAP(-/-) astrocytes than GFAP(+/+) astrocytes, suggesting the presence of a larger ECS around GFAP(-/-) astrocytes. Astrocyte swelling evoked by application of 50 mM K(+) or by hypotonic solution (HS) produced a larger increase in [K(+)](e) around GFAP(+/+) astrocytes than around GFAP(-/-) astrocytes. No differences in alpha and lambda in the spinal cord or cortex of GFAP(+/+) and GFAP(-/-) mice were found; however, the application of either 50 mM K(+) or HS in spinal cord, or SD in cortex, evoked a large decrease in alpha and an increase in lambda in GFAP(+/+) mice only. Slower swelling in GFAP(-/-) astrocytes indicates that GFAP and intermediate filaments play an important role in cell swelling during pathological states. 相似文献
37.
Yulia M. Ulybina Ekatherina Sh. Kuligina Nathalia V. Mitiushkina Maxim E. Rozanov Alexandr O. Ivantsov Daria N. Ponomariova Alexandr V. Togo Evgeny V. Levchenko Vladimir A. Shutkin Sergiu I. Brenister Peter Devilee Boris Zhivotovsky Ari Hirvonen Evgeny N. Imyanitov 《Cancer letters》2009
Apoptosis plays a role in the elimination of DNA-damaged cells thus protecting the host from cancer development. Some data indicate that normal variations within the sequence of apoptotic genes may lead to suboptimal apoptotic capacity and therefore increased cancer risk. We tested 19 coding apoptotic gene SNPs in 2-stage molecular epidemiological study. For the preliminary sorting of SNP candidates, we employed a “comparison of extremes” approach, where 111 patients with highly pronounced LC susceptibility (non-smokers or young-onset light smokers) were analyzed against 110 subjects with the evidence for LC tolerance (elderly tumor-free heavy smokers). Three genotypes demonstrated possible association with LC risk (Leu/Leu-homozygotes for Casp5 Val318Leu versus other genotypes: OR = 2.47 (95% CI: 1.07–5.69), p = 0.03; His-carriers for Casp8 His302Asp: OR = 2.26 (95% CI: 1.18–4.31), p = 0.02; Arg-carriers for DR4 Lys441Arg: OR = 1.89 (95% CI: 1.05–3.40), p = 0.03), and therefore were selected for the validation. The extended study included 2 case-control series, namely subjects from Russia (351 LC cases and 538 controls) and Moldova (296 LC cases and 295 controls). Interestingly, all three candidate genotypes consistently demonstrated OR above 1 both in Russian and in Moldovian groups. Although the combined Mantel–Haenszel analysis yet failed to reach statistical significance (OR = 1.22 (95% CI: 0.90–1.65), p = 0.21; OR = 1.17 (95% CI: 0.92–1.50), p = 0.21; OR = 1.19 (95% CI: 0.95–1.51), p = 0.14, respectively), the obtained data indicate that Casp5, Casp8 and DR4 gene polymorphisms may deserve consideration in large-scale case-control studies of LC risk modifiers. 相似文献
38.
Andrei A. Savchenko Elena Tikhonova Igor Kudryavtsev Dmitry Kudlay Ilya Korsunsky Vasily Beleniuk Alexandr Borisov 《Viruses》2022,14(3)
Background: T and B cell-mediated immunity can be assessed using T cell receptor excision circle (TREC) and Kappa-deleting recombination excision circle (KREC) analysis, respectively, and successful implementation of this method requires evaluation of the correlation between the TREC frequencies and T cell subsets as well as KREC levels and B lymphocyte subsets. The aim of the present study was to evaluate the correlation between the TREC/KREC concentrations and T/B lymphocyte subsets at different stages of COVID-19. Methods: We examined 33 patients in the acute stage of COVID-19 (including 8 patients with poor outcomes) and 33 COVID-19 survivors. TREC/KREC concentrations were measured using quantitative real-time PCR. T/B lymphocyte subsets were determined using flow cytometry. Results: Blood TREC and KREC levels were found to be significantly lower in the acute stage of COVID-19 compared to control values. Moreover, a zero blood TREC level was a predictor of a poor disease outcome. Reductions in CD3+CD4+CD45RO−CD62L− and CD3+CD8+CD45RO−CD62L− T cell counts (as well as in the main fractions of B1 and B2 B cells) indicated a favorable outcome in COVID-19 patients in the acute stage of the disease. Decreased CD3+CD4+CD45RO−CD62L+ and CD3+CD8+CD45RO−CD62L+ T cell frequencies and increased CD3+CD8+CD45RO−CD62L− cell counts were found to indicate a poor outcome in patients with acute COVID-19. These patients were also found to have increased B1 cell counts while demonstrating no changes in B2 cell counts. The levels of effector T cell subsets an naïve B cells were normal in COVID-19 survivors. The most pronounced correlations between TREC/KREC levels and T/B cell subsets counts were observed in COVID-19 survivors: there were positive correlations with naïve T and B lymphocytes and negative correlations with central and effector memory T cell subsets. Conclusions: The assessment of correlations between TREC and T cell subsets as well as KREC levels and B cell subset counts in patients with acute COVID-19 and COVID-19 survivors has shown that blood concentrations of TREC and KREC are sensitive indicators of the stage of antigen-independent differentiation of adaptive immunity cells. The results of the TREC and KREC analysis correlated with the stages of COVID-19 and differed depending on the outcome of COVID-19. 相似文献
39.
Bazhin AV Dalke C Willner N Abschütz O Wildberger HG Philippov PP Dummer R Graw J de Angelis MH Schadendorf D Umansky V Eichmüller SB 《International journal of cancer. Journal international du cancer》2009,124(1):140-149
Melanoma-associated retinopathy is a rare paraneoplastic neurological syndrome characterized by retinopathy in melanoma patients. The main photoreceptor proteins have been found to be expressed as cancer-retina antigens in melanoma. Here we present evidence that these can function as paraneoplastic antigens in melanoma-associated retinopathy. Sera and one tumor cell line of such patients were studied and ret-transgenic mice spontaneously developing melanoma were used as a murine model for melanoma-associated retinopathy. Splenocytes and sera were used for adoptive transfer from tumor-bearing or control mice to wild-type mice. Retinopathy was investigated in mice by funduscopy, electroretinography and eye histology. Expression of photoreceptor proteins and autoantibodies against arrestin and transducin were detected in melanoma-associated retinopathy patients. In tumor-bearing ret-transgenic mice, retinopathy was frequently (13/15) detected by electroretinogram and eye histology. These pathological changes were manifested in degenerations of photoreceptors, bipolar cells and pigment epithelium as well as retinal detachment. Mostly these defects were combined. Cancer-retina antigens were expressed in tumors of these mice, and autoantibodies against arrestin were revealed in some of their sera. Adoptive transfer of splenocytes and sera from tumor-bearing into wild-type mice led to the induction of retinopathy in 4/16 animals. We suggest that melanoma-associated retinopathy can be mediated by humoral and/or cellular immune responses against a number of cancer-retina antigens which may function as paraneoplastic antigens in melanoma-associated retinopathy. 相似文献
40.
Pattanasak Mongkolwat Ph.D. Alexandr Kogan B.S. Jennifer Koh M.S. David S. Channin M.D. 《Journal of digital imaging》2005,18(4):326-332
Acquiring, implementing, and maintaining a picture archiving and communication system (PACS) is an enduring and complex endeavor.
A large-scale project such as this requires efficient and effective communication among a large number of stakeholders, sharing
of complex documentation, recording ideas, experiences, and events such as meetings, and project milestones to succeed. Often,
mass-market technologies designed for other purposes can be used to solve specific complex problems in healthcare. In this
case, we wanted to explore the role of popular weblogging or “blogging” software to meet our needs. We reviewed a number of
well-known blog software packages and evaluated them based on a set of criteria. We looked at simplicity of installation,
configuration, and management. We also wanted an intuitive, Web-based interface for end-users, low cost of ownership, use
of open source software, and a secure forum for all PACS team members. We chose and implemented the Invision Power Board for
two purposes: local PACS administrative purposes and for a national PACS users' group discussion. We conclude that off the
shelf, state-of-the-art, mass-market software such as that used for the currently very popular purpose of weblogging or “blogging”
can be very useful in managing the variety of communications necessary for the successful implementation of PACS. 相似文献