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121.
To examine the urinary excretion of opiates and their metabolites following inhalation exposure of rats to opium, analytical procedures for the simultaneous determination of the compounds in opium, the vapor derived by the volatilization of opium and the urine of rats exposed to the opium vapor were developed using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). Seven compounds were determined in the opium, namely morphine, codeine, thebaine, noscapine, papaverine, meconic acid and meconin. All seven were extracted with 2.5% acetic acid solution and subjected to LC-APCI-MS analysis. The separation was performed on an ODS column in acetonitrile-50 mM ammonium formate buffer (pH 3.0) using a linear gradient program and quantitative analysis was carried out in the selected ion monitoring mode ([M+H](+)). For the analysis of the volatilization of opium, the opium (1 g) was added to a glass pipe, which was then heated at 300 degrees C for 20 min. Negative pressure (air flow-rate; 300 ml/min) was used to draw the vapor through a series of glass wool and methanol traps. The total amount of each compound in the vapor was estimated by measurement of the compounds trapped in the glass wool and methanol. Wister rats (n=3) were exposed to the vapor derived from the volatilization system and the urinary amounts (0-72 h) of the six opiates and metabolites including morphine-3-grucronide (M3G) and morphine-6-grucronide (M6G) were measured after solid-phase extraction. The calibration curves for those compounds in the rat urine were linear over the concentration range 10-500 ng/ml. The recoveries for each analyte from the rat urine sample spiked with standard solution were generally greater than 80%, and the relative standard deviation for the analytical procedure was less than 8% with the exception of meconin. After inhalation exposure of rats to opium, M3G (5.45-14.38 micro g), morphine (2.27-4.65 micro g), meconin (0.54-1.85 micro g), codeine (0.54-1.85 micro g), noscapine (0.34-0.40 micro g) and papaverine (0.01-0.04 micro g) were detected in the urine over 72 h. However, only trace levels of thebaine were observed despite it being one of the major alkaloids found in the opium. On the other hand, a relatively large amount of meconin was detected in the vapor and the urine as compared with the opium. It is suggested that the presence of meconin in biological fluids could be indicative of opium ingestion by inhalation.  相似文献   
122.
IL-11 inhibits the activation of NF-kappaB and induces the Th2 polarization of CD4+ T cells. The clinical utility of IL-11 is being investigated in Crohn's disease. However, physiological secretion of IL-11 in the intestine remains unclear. In this study, we investigated IL-11 secretion in human intestinal subepithelial myofibroblasts (SEMFs). Intestinal SEMFs were isolated from the human colonic mucosa. IL-11 secretion and mRNA expression were determined by ELISA and Northern blot analysis. The activating protein (AP)-1-DNA binding activity was evaluated by EMSA. IL-11 secretion was induced by IL-1beta and transforming growth factor (TGF)-beta1. These were also observed at the mRNA level. The EMSAs demonstrated that both IL-1beta and TGF-beta1 induced AP-1 activation within 2 h after stimulation, and a blockade of AP-1 activation by the recombinant adenovirus containing a dominant negative c-Jun markedly reduced the IL-1beta- and TGF-beta1-induced IL-11 mRNA expression. IL-1beta and TGF-beta1 induced an activation of ERK p42/44 and p38 MAP kinases, and the MAP kinase inhibitors (SB-202190, PD-98059, and U-0216) significantly reduced the IL-1beta- and TGF-beta1-induced IL-11 secretion. The upregulation of IL-11 mRNA by IL-1beta- and TGF-beta1 was also mediated by a p38 MAP kinase-mediated mRNA stabilization. The combination of IL-1beta and TGF-beta1 additively enhanced IL-11 secretion. Intestinal SEMFs secreted IL-11 in response to IL-1beta- and TGF-beta1. Mucosal IL-11 secretion might be important as an anti-inflammatory response in the pathogenesis of intestinal inflammation.  相似文献   
123.
AIM: The roles of adrenomedullin (AM) in body fluid balance under general anesthesia were investigated. METHODS: Time course changes in plasma osmolality, AM, arginine vasopressin (AVP), and urinary aquaporin 2 (AQP2) in 17 patients undergoing abdominal surgery under general anesthesia were examined. RESULTS: Increases in plasma AM levels were observed in parallel with increases in the levels of urinary AQP2/creatinine (Cr) before induction and 90 and 180 min after initiation of anesthesia. Significant correlations between plasma AM and urinary AQP2/Cr (r = 0.62, p < 0.0001) as well as urinary AVP/Cr and AQP2/Cr (r = 0.60, p < 0.0001) were uncovered. Multivariate stepwise analysis identified plasma AM as the critical independent factor affecting urinary AQP2/Cr level. CONCLUSION: A novel correlation of AM and AQP2 which overlays an AVP-AQP2 system may play a key role in fluid homeostasis during general anesthesia.  相似文献   
124.
The present study was undertaken to determine the effects of AT1 receptor blockade which occurred in response to losartan, on the extracellular matrix (ECM) degradation process in the Bio 14.6 (n = 12) and Bio 53.58 (n = 12) strains which are referred as models of hypertrophic and dilated cardiomyopathy, respectively. The administration of losartan (30 mg/kg/day) in hamsters from 10–20 weeks of age reduced the accumulation of the left ventricular collagen matrix in both of the Bio 14.6 and the Bio 53.58 strains. According to the RTPCR, the levels of mRNA for matrix metalloproteinase (MMP) and the tissue inhibitor of MMP (TIMP) were examined. MMP1, 2, 3, and 9 were more enhanced in both myopathic strains than in the control F1 strains. With losartan, the levels of MMP1, 2, 9, TIMP1 and 2 decreased in the both strains but those for MMP3 did not in Bio 14.6 strains. TIMP3 and 4 mRNA levels did not change in any of the experimental hamsters, whether treated or untreated with losartan. The Western blots also showed similar observations in the both strains as seen in mRNA expressions although MMP2 in the Bio 53.58 strains did not differ between treated and untreated with losartan. Although losartan has an inhibitory effect on collagen accumulation in the development of cardiomyopathy, MMPs (1, 2, 9) and TIMPs (1, 2) seem to be susceptible to responding to losartan in Bio cardiomyopathic hamsters.  相似文献   
125.
BACKGROUND: Recently, an endothelin (ET-1) with a potent vasoconstrictive activity and stimulative activity of vascular muscular cell growth was discovered and blood ET-1 levels were higher in diabetic patients than in healthy subjects, suggesting that high ET-1 levels assist development and progression of diabetic microangiography. METHODS: We examined renal function, and serum and tissue ET-1 levels in streptozotocin (STZ)-induced diabetic rats treated with a prostaglandin (PG) I(2) derivative to investigate the effect of PGI(2) in diabetic vascular disturbance. RESULTS: Renal weight, urinary albumin, urinary N-acetyl-beta,D-glucosaminidase (NAG) and serum ET-1 levels increased in STZ-induced diabetic rats, and a tendency to increase in renal tissue ET-1 levels was observed. Furthermore, electron-microscopic findings in the kidneys showed mesangial cell proliferation and mesangial matrix expansion which might be caused by diabetic nephropathy. The PGI(2) derivative reduced urinary albumin and NAG levels in STZ-induced rats. It was considered, therefore, that the PGI(2) derivative is effective in diabetic nephropathy. As the PGI(2) derivative also reduced renal tissue ET-1 levels, improvement of diabetic nephropathy partially was considered to result from the reduction of renal tissue ET-1 levels. CONCLUSION: In STZ-induced rats, increased serum ET-1 levels and a tendency to increase in renal tissue ET-1 levels were associated with increases in urinary albumin and NAG levels, and these levels were decreased by a PGI(2) derivative. These findings suggested that increased ET-1 concentrations assist development and progression of diabetic nephropathy, especially diabetic microangiopathy, and the PGI(2) derivative may be effective for inhibition of diabetic microangiopathy mediated by reduction of ET-1 concentrations.  相似文献   
126.
By detailed NMR analysis of a human telomere repeating unit, d(CCCTAA), we have found that three distinct tetramers, each of which consists of four symmetric single-strands, slowly exchange in a slightly acidic solution. Our new finding is a novel i-motif topology (T-form) where T4 is intercalated between C1 and C2 of the other duplex. The other two tetramers have a topology where C1 is intercalated between C2 and C3 of the other parallel duplex, resulting in the non-stacking T4 residues (R-form), and a topology where C1 is stacked between C3 and T4 of the other duplex (S-form). From the NMR denaturation profile, the R-form is the most stable of the three structures in the temperature range of 15–50°C, the S-form the second and the T-form the least stable. The thermodynamic parameters indicate that the T-form is the most enthalpically driven and entropically opposed, and its population is increased with decreasing temperature. The T-form structure determined by restrained molecular dynamics calculation suggests that inter-strand van der Waals contacts in the narrow grooves should contribute to the enthalpic stabilization of the T-form.  相似文献   
127.
A processing The processing pathway of N-glycans in Carica papaya was deduced from the structures of N-glycans. The N-glycans were liberated by hydrazinolysis followed by N-acetylation. Their reducing-end sugar residues were tagged with 2-aminopyridine and the pyridylamino (PA-) sugar chains thus obtained were purified by HPLC. Eleven PA-sugar chains were found, and their structures were analyzed by two-dimensional sugar mapping combined with partial acid hydrolysis and exoglycosidase digestion. The structures of the N-glycans were of the highmannose types with xylose and fucose; however, among them two new N-glycans, Manalpha1-6(Manalpha1-3)Manalpha1-6(Xylbeta1-2)+ ++Manbeta1-4GlcNAcbeta1- 4(Fucalpha1-3)GlcNAc and Manalpha1-3Manalpha1-6(Xylbeta1-2)Manbeta1-4G lcNAcbeta1-4(Fucalpha1-3 )GlcNAc, were found. Judging from these structures together with Manalpha1-6(Manalpha1-3)Manalpha1-6(Manalpha1-3) (Xylbeta1-2)Manbeta1- 4GlcNAcbeta1-4(Fucalpha1-3)GlcNAc reported previously [Shimazaki, A., Makino, Y., Omichi, K., Odani, S., and Hase, S. (1999) J. Biochem. 125, 560- 565], a processing pathway for N-glycans in C. papaya is inferred in which the activity of Golgi alpha-mannosidase II is incomplete.  相似文献   
128.
The Otsuka Long-Evans Tokushima fatty (OLETF) rat is an animal model of type 2 diabetes, characterized by abdominal obesity, insulin resistance, hypertension, and dyslipidemia. To elucidate the underlying molecular mechanism of obesity and its related complications, we used representational difference analysis and identified the genes more abundantly and specifically expressed in the visceral adipose tissue (VAT) of obese OLETF rats compared with the diabetes-resistant counterpart, that is, Long-Evans Tokushima Otsuka (LETO) rats. By Northern blot analysis, we confirmed the differential expression of 13 genes, including 3 novel genes. The upregulated expression of well-characterized lipid metabolic enzymes, such as lipoprotein lipase, phosphoenolpyruvate carboxykinase, and cholesterol esterase, were observed in VAT of OLETF rats. We demonstrated the differential expression of secreted proteins in VAT of OLETF rats, such as thrombospondin 1 and contrapsin-like protease inhibitor. In contrast to lipid enzymes, the secreted proteins revealed exclusive mRNA expression and they were not detected in VAT of LETO rats. Furthermore, the novel genes OL-16 and OL-64 were also expressed specifically in VAT of OLETF rats and were absent in that of LETO rats and other tissues, including subdermal and brown adipose tissues. The C-terminal partial amino acid sequence of OL-64 revealed that it showed approximately 40% homology with alpha(1)-antitrypsin and it seemed to be a new member of the serine proteinase inhibitor (SERPIN) gene family. VAT of OLEFT rats had a unique gene expression profile, and the accumulated VAT-specific known and novel secreted proteins may play a role(s) in the pathogenesis of obesity and its related complications.  相似文献   
129.
An outbreak caused by salted salmon roe contaminated with enterohemorrhagic Escherichia coli O157 occurred in Japan in 1998. Since about 0.75 to 1.5 viable cells were estimated to cause infection, we presumed that O157 might enter the viable but nonculturable (VNC) state in salted salmon roe and consequently that viable cell numbers might be underestimated. Although patient-originating O157 cells could not grow on agar plates after 72 h of incubation in 13% NaCl, they were resuscitated in yeast extract broth, and more than 90% of the cells were shown to be viable by fluorescent staining, suggesting that almost all of them could enter the VNC state in NaCl water. Roe-originating O157 was resistant to NaCl because it could grow on agar after 72 h of incubation in NaCl water, but about 20% of cells appeared to enter the VNC state. Therefore, germfree mice were infected with O157 to examine the resuscitation of cells in the VNC state and the retention of pathogenicity. O157 that originated in roe, but not patients, killed mice and was isolated from the intestine. However, these isolates had become sensitive to NaCl. O157 cells of roe origin incubated in normal media also killed mice and were isolated from the intestine, but they also became transiently NaCl sensitive. We therefore propose that bacterial cells might enter the VNC state under conditions of stress, such as those encountered in vivo or in high salt concentrations, and then revive when those conditions have eased. If so, the VNC state in food is potentially dangerous from a public health viewpoint and may have to be considered at the time of food inspection. Finally, the establishment of a simple recovery system for VNC cells should be established.  相似文献   
130.
The Skn7 response regulator has previously been shown to play a role in the induction of stress-responsive genes in yeast, e.g., in the induction of the thioredoxin gene in response to hydrogen peroxide. The yeast Heat Shock Factor, Hsf1, is central to the induction of another set of stress-inducible genes, namely the heat shock genes. These two regulatory trans-activators, Hsf1 and Skn7, share certain structural homologies, particularly in their DNA-binding domains and the presence of adjacent regions of coiled-coil structure, which are known to mediate protein-protein interactions. Here, we provide evidence that Hsf1 and Skn7 interact in vitro and in vivo and we show that Skn7 can bind to the same regulatory sequences as Hsf1, namely heat shock elements. Furthermore, we demonstrate that a strain deleted for the SKN7 gene and containing a temperature-sensitive mutation in Hsf1 is hypersensitive to oxidative stress. Our data suggest that Skn7 and Hsf1 cooperate to achieve maximal induction of heat shock genes in response specifically to oxidative stress. We further show that, like Hsf1, Skn7 can interact with itself and is localized to the nucleus under normal growth conditions as well as during oxidative stress.  相似文献   
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