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951.
CC Chen SS Wang SH Tsay FY Lee SL Wu RH Lu FY Chang SD Lee 《Canadian Metallurgical Quarterly》1998,19(3):543-547
The effects of somatostatin and octreotide (a long acting somatostatin analogue) in acute pancreatitis are inconclusive. This study examined the prophylactic and therapeutic effects of different doses of octreotide on retrograde sodium taurodeoxycholate-induced acute necrotizing pancreatitis in rats. The rats were divided into 4 groups receiving subcutaneous injection of saline, octreotide 10 microg/kg, 20 microg/kg at 0, 8 and 16 h and octreotide 20 microg/kg at 5, 13 and 21 h, separately. The serum levels of amylase and lipase, pancreatic histopathology, mortality and hemodynamics were examined. Octreotide significantly reduced serum levels of amylase and lipase at 12 h and the degree of pancreatic edema, necrosis and hemorrhage at 18-24 h as compared to the control group. Prophylactic octreotide 10 microg/kg significantly decreased the 24-h mortality from 100% to 44.4% (p < 0.05). The 24-h mortality further reduced to 12.5% and 10% with prophylactic and therapeutic octreotide 20 microg/kg, respectively. The decrease of mean arterial pressure at 12 h was significantly lower in octreotide groups than in the control group. We conclude that octreotide improves pancreatic histopathology and survival in acute necrotizing pancreatitis in rats. 相似文献
952.
RH van den Berg MC Faber-Krol RB Sim MR Daha 《Canadian Metallurgical Quarterly》1998,161(12):6924-6930
We and others have demonstrated previously the occurrence of cC1qR/CaR, a receptor for the collagen-like stalks of complement component C1q, on endothelial cells. In the present study we investigated whether binding of C1q to endothelial cells resulted in enhancement of cytokine or chemokine production. HUVEC produced 82 +/- 91 pg/ml of IL-8, 79 +/- 113 pg/ml of IL-6, and 503 +/- 221 pg/ml of monocyte chemoattractant peptide-1 (MCP-1) under basal conditions. Incubation with C1q resulted in a time- and dose-dependent up-regulation of IL-8 (1012 +/- 43 pg/ml), IL-6 (392 +/- 20 pg/ml), and MCP-1 (2450 +/- 101 pg/ml). This production is dependent on de novo protein synthesis, as demonstrated by the detection of specific mRNA after C1q stimulation, and inhibition of peptide production in the presence of cycloheximide. The production of all factors was inhibited (69 +/- 7%) by the collagenous fragments of C1q, while the C1q globular heads only induced 13 +/- 11% inhibition. When HUVEC were incubated with C1q in the presence of aggregated IgM, enhanced production of IL-8 (2500 +/- 422 pg/ml), IL-6 (997 +/- 21 pg/ml), and MCP-1 (5343 +/- 302 pg/ml) was found. Furthermore, F(ab')2 anti-calreticulin partially inhibited the production of IL-8, confirming at least the involvement of cC1qR/CaR. These experiments suggest that in an inflammatory response C1q not only is able to activate the complement pathway, but when presented in a proper fashion also might induce the production of factors that contribute to acute phase responses and recruitment of inflammatory cells. 相似文献
953.
George N. Henderson Patrick O. Whalen Rebecca A. Darr Stephen H. Curry Hartmut Derendorf Thomas G. Baumgartner Peter W. Stacpoole 《Drug development and industrial pharmacy》1994,20(15):2425-2437
Dichloroacetate (DCA) is an investigational drug for the treatment of several metabolic and cardiovascular disorders. Hitherto, it has been used mostly in intravenous, short term treatment regimens. Chronic administration of the drug may be toxic, due in part to the depletion of tissue thiamine stores. We therefore developed a stable liquid preparation of the sodium salt of DCA and thiamine HCl suitable for chronic oral administration. The DCA-thiamine mixture is formulated as a palatable solution containing glycerol, sodium benzoate and aspartame in phosphate buffer at pH 3.5. A thermally accelerated decomposition study of the oral DCA formulation revealed a shelf-life of about 5 years at 4°C and about 156 days at 25°C. The stability was also followed for 1 year at its storage condition of 4°C and it was found to be stable at least for 1 year, which is its current recommended storage time. A new high performance liquid chromatographic method was developed to quantitate DCA, thiamine, aspartame and sodium benzoate in the formulation. The DCA-thiamine formulation is palatable and well tolerated by children, some of whom have received it continuously for over three years. Under chronic treatment, at a dose of 12.5 mg/Kg or 25 mg/Kg, DCA has a mean plasma half life of 7.9 hrs in children with congenital lactic acidosis. 相似文献
954.
A Ramirez-Ramos RH Gilman R Leon-Barua S Recavarren-Arce J Watanabe G Salazar W Checkley J McDonald Y Valdez L Cordero J Carrazco 《Canadian Metallurgical Quarterly》1997,25(5):1027-1031
Helicobacter pylori is associated with gastritis, peptic ulcer disease, and gastric cancer. Since gastric cancer is common in Peru, eradication of H. pylori may help to reduce the occurrence of gastric cancer. This study involved three randomized trials to determine the efficacy of four different triple-drug therapy regimens. The most successful regimen was furazolidone combined with bismuth subsalicylate and amoxicillin, which eradicated infection in 82% of patients. Patients successfully treated were followed every 2-3 months to determine the recurrence rate of H. pylori infection. Of 105 patients with H. pylori eradication documented by pathology and culture, 52% (55) returned for follow-up endoscopy, and in 73% (40) of these 55 the infection recurred during the 8-month follow-up period. Thirty-five patients from whom H. pylori was eradicated and who were tested for antibodies to H. pylori remained consistently seropositive. Rapid recurrence of H. pylori infection after successful eradication suggests that measures other than antimicrobial therapy are needed to fight H. pylori in developing countries. 相似文献
955.
Extraintestinal involvement of Crohn's disease is becoming more readily identified. Laryngeal involvement by Crohn's disease, however, has been reported in only five cases in the medical literature. We present the sixth case as well as an analysis of the prior reports. 相似文献
956.
957.
RH Gottlieb R Tan J Widjaja PJ Fultz WB Robinette DJ Rubens 《Canadian Metallurgical Quarterly》1998,171(3):697-701
To establish a possible correlation between the rate of cellular proliferation and already documented functional and morphological characteristics of the rat pineal gland during postnatal development, the bromodeoxyuridine labelling method was used to evaluate the fraction of cells at the S phase of the cell cycle in paraffin sections from 1-, 7-, 14- and 28-day-old rats. Numerical density, taken as an indirect measure of cell hypertrophy, was also evaluated. During the first week after birth the percentage of S phase-cells in the rat pineal gland sharply decreased from around 9% to 1.3%. A smaller but also significant decrease was found from the 7th to the 14th postnatal day where S phase cells were less than 0.5% of all pineal cells. A very low percentage was also seen in samples from 28-day-old rats. Numerical density, namely, the total number of cells per surface unit of pineal section, decreased from birth to the end of the first month. This decrease was also steeper from birth to the 7th postnatal day than at any other period of the study. These results support the idea that a strong expansion of the cellular population of the rat pineal gland precedes morphological and functional maturation and opens the way to further exploration of the relationship between functional and proliferative responses of the pineal gland. 相似文献
958.
DK Vassilatis JP Arena RH Plasterk HA Wilkinson JM Schaeffer DF Cully LH Van der Ploeg 《Canadian Metallurgical Quarterly》1997,272(52):33167-33174
Avermectins are a class of macrocyclic lactones that is widely used in crop protection and to treat helminth infections in man and animals. Two complementary DNAs (GluClalpha and GluClbeta) encoding chloride channels that are gated by avermectin and glutamate, respectively, were isolated from Caenorhabditis elegans. To study the role of these subunits in conferring avermectin sensitivity we isolated a mutant C. elegans strain with a Tc1 transposable element insertion that functionally inactivated the GluClalpha gene (GluClalpha::Tc1). GluClalpha::Tc1 animals exhibit a normal phenotype including typical avermectin sensitivity. Xenopus oocytes expressing GluClalpha::Tc1 strain mRNA elicited reduced amplitude avermectin and glutamate-dependent chloride currents. Avermectin binding assays in GluClalpha::Tc1 strain membranes showed the presence of high affinity binding sites, with a reduced Bmax. These experiments suggest that GluClalpha is a target for avermectin and that additional glutamate-gated and avermectin-sensitive chloride channel subunits exist in C. elegans. We isolated a cDNA (GluClalpha2) encoding a chloride channel that shares 75% amino acid identity with GluClalpha. This subunit forms homomeric channels that are gated irreversibly by avermectin and reversibly by glutamate. GluClalpha2 coassembles with GluClbeta to form heteromeric channels that are gated by both ligands. The presence of subunits related to GluClalpha may explain the low level and rarity of target site involvement in resistance to the avermectin class of compounds. 相似文献
959.
960.
To study the immune response within the subarachnoid space in patients with neurocysticercosis, we measured the cerebrospinal fluid contents of immunoglobulins A, E, G, and M in 38 patients and the contents of the proinflammatory cytokines TNF-alpha, IL-1b, IL-6 and IFN-gamma in 17 patients. The same measurements were made in 30 neurological patients without inflammatory or immune-mediated disorders. Each immunoglobulin and cytokine, including the gender and age of the patient, was compared by multiple regression analysis with the CSF contents of cells, protein and ELISA for cysticercal antigens. A direct correlation was found of IgM with cell content (p < 0.058) and with ELISA values (p < 0.027); of age with protein content (p < 0.006); of IL-6 with protein content (p < 0.018) and of IL-1b with ELISA values (p < 0.004). An inverse correlation was found of glucose with ELISA values (p < 0.008). A complex function of the immune response within the subarachnoid space was observed: mean values of IgG, IgM, IgE and interleukins 1b and 6 were increased, whereas values of IgA, TNF-alpha and IFN-gamma were similar to those of controls. 相似文献