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31.
32.
L Ohno-Machado JH Gennari SN Murphy NL Jain SW Tu DE Oliver E Pattison-Gordon RA Greenes EH Shortliffe GO Barnett 《Canadian Metallurgical Quarterly》1998,5(4):357-372
Carboxylate and sulfate groups were introduced at the surface of poly(ethylene) (PE) samples. This was accomplished by coating and immobilizing sodium 10-undecenoate (C11(:)) and 10-undecene sulfate (S11(:)) on the polymer by means of an argon plasma treatment. The composition of the coated surfactant layer was proportional to the composition of the coating solution. The thickness of the surfactant layer on the surface of PE samples, which were precoated from an aqueous solution with a total surfactant concentration of 0.30 M, was about 55 A. The presence of carboxylate and sulfate groups after plasma treatment of the precoated surfaces was confirmed by X-ray photoelectron spectroscopy (XPS). About 20% of the initial amount of functional groups of the coated surfactants was retained at the PE surface. The ratio of carboxylate/sulfate groups at the plasma treated surfaces was dependent on the composition of the precoated surfaces. The minimum surface density of these groups on the resulting samples was about one group per 40 A2. 相似文献
33.
AE Medvedev T Flo RR Ingalls DT Golenbock G Teti SN Vogel T Espevik 《Canadian Metallurgical Quarterly》1998,160(9):4535-4542
This study was undertaken to evaluate the role of CD14 and complement receptors type 3 (CR3) and 4 (CR4) in mediating TNF release and NF-kappaB activation induced by LPS and cell wall preparations from group B streptococci type III (GBS). LPS and GBS caused TNF secretion from human monocytes in a CD14-dependent manner, and soluble CD14, LPS binding protein, or their combination potentiated both LPS- and GBS-induced activities. Blocking of either CD14 or CD18, the common beta-subunit of CR3 and CR4, decreased GBS-induced TNF release, while LPS-mediated TNF production was inhibited by anti-CD14 mAb only. Chinese hamster ovary cell transfectants (CHO) that express human CD14 (CHO/CD14) responded to both LPS and GBS with NF-kappaB translocation, which was inhibited by anti-CD14 mAb and enhanced by LPS binding protein. While LPS showed fast kinetics of NF-kappaB activation in CHO/CD14 cells, a slower NF-kappaB response was induced by GBS. LPS also activated NF-kappaB in CHO cells transfected with either human CR3 or CR4 cDNA, although responses were delayed and weaker than those of CHO/CD14 cells. In contrast to LPS, GBS failed to induce NF-kappaB in CHO/CR3 or CHO/CR4 cells. Both C3H/OuJ (Lps[n]) and C3H/HeJ (Lps[d]) mouse peritoneal macrophages responded to GBS with TNF production and NF-kappaB translocation, whereas LPS was active only in C3H/OuJ macrophages. Thus, LPS and GBS differentially involve CD14 and CR3 or CR4 for signaling NF-kappaB activation in CHO cells and TNF release in human monocytes, and engage a different set of receptors and/or intracellular signaling pathways in mouse macrophages. 相似文献
34.
JJ Gao MB Filla MJ Fultz SN Vogel SW Russell WJ Murphy 《Canadian Metallurgical Quarterly》1998,161(9):4803-4810
35.
A Guhlmann D Brecht-Krauss G Suger G Glatting J Kotzerke L Kinzl SN Reske 《Canadian Metallurgical Quarterly》1998,39(12):2145-2152
The aim of this study was to assess the usefulness of PET with 2-18F-fluoro-2-deoxy-D-glucose (FDG), as compared to immunoscintigraphy (IS) with 99mTc-labeled monoclonal antigranulocyte antibodies (AGAbs), in the detection of chronic osteomyelitis. METHODS: Fifty-one patients suspected of having chronic osteomyelitis in the peripheral (n = 36) or central (n = 15) skeleton were evaluated prospectively with static FDG PET imaging and combined 99mTc-AGAb/99mTc-methylene diphosphonate (MDP) bone scanning within 5 days. FDG PET and IS were evaluated in a blinded and independent manner by visual interpretation, which was graded on a five-point scale of two observers' confident diagnosis of osteomyelitis. Receiver operating characteristic (ROC) curve analysis was performed for both imaging modalities. The final diagnosis was established by means of bacteriologic culture of surgical specimens and histopathologic analysis (n = 31) or by biopsy and clinical follow-up over 2 yr (n = 20). RESULTS: Of 51 patients, 28 had osteomyelitis and 23 did not. According to the unanimous evaluation of both readers, FDG PET correctly identified 27 of the 28 positives and 22 of the 23 negatives (IS identified 15 of 28 positives and 17 of 23 negatives, respectively). The area under the ROC curve was 0.97/0.97 (reader 1/reader 2) for FDG PET and 0.87/0.90 for IS, with a high degree of interobserver concordance (K-values were 0.96 for FDG PET and 0.91 for IS). In the central skeleton, the ROC curve area was 0.98/1.00 for FDG PET and 0.71/0.77 for IS (p<0.05). On the basis of ROC analysis, the overall accuracies of FDG PET and IS in the detection of chronic osteomyelitis were 96%/96% and 82%/ 88%, respectively. With regard to the optimal threshold values, sensitivity and specificity were 100%/97% and 95%/95% with FDG PET, compared to 86%/92% and 77%/82% with IS, respectively. CONCLUSION: In the peripheral skeleton, both FDG PET and combined 99mTc-AGAb/99mTc-MDP scanning are appropriate imaging modalities to diagnose chronic osteomyelitis. FDG PET additionally allows reliable differentiation between osteomyelitis and infection of the surrounding soft tissue. In the central skeleton within active bone marrow, FDG PET is highly accurate and superior to AGAb imaging in the diagnosis of chronic osteomyelitis, which frequently presents as a nonspecific photopenic lesion at scintigraphy with labeled white blood cells. 相似文献
36.
WR Schwan SN Coulter EY Ng MH Langhorne HD Ritchie LL Brody S Westbrock-Wadman AS Bayer KR Folger CK Stover 《Canadian Metallurgical Quarterly》1998,66(2):567-572
Staphylococcus aureus is an important pathogen of humans and other animals, causing bacteremia, abscesses, endocarditis, and other infectious syndromes. A signature-tagged mutagenesis (STM) system was adapted for use in studying the genes required for in vivo survival of S. aureus. An STM library was ultimately created in S. aureus RN6390, with Tn917 being used to create the transposon mutations. Pools of S. aureus RN6390 mutants were screened in mouse abscess, bacteremia, and wound infection models for growth attenuation after in vivo passage. One of the mutants that was identified displayed marked attenuation following large-pool screening in all three animal models, which was confirmed in bacteremia and endocarditis models of infection with a smaller pool of mutants. Sequence analysis of the entire open reading frame showed a 99% identity to the high-affinity proline permease (putP) gene characterized in another strain of S. aureus. In wound and murine abscess infection models, the putP mutant was approximately 10-fold more attenuated than was wild-type strain RN6390. Another S. aureus strain transduced with the putP mutation also displayed an attenuated phenotype after passage in the wound model. A [3H]proline uptake assay showed that less proline was specifically transported into the putP mutant than into strain RN6390. The reduced viability of the bacteria possessing the mutation in the S. aureus high-affinity proline permease suggests that proline scavenging by the bacteria is important for in vivo growth and proliferation and that analogs of proline may serve as potential antistaphylococcal therapeutic agents. 相似文献
37.
IM Bell JM Erb RM Freidinger SN Gallicchio JP Guare MT Guidotti RA Halpin DW Hobbs CF Homnick MS Kuo EV Lis DJ Mathre SR Michelson JM Pawluczyk DJ Pettibone DR Reiss S Vickers PD Williams CJ Woyden 《Canadian Metallurgical Quarterly》1998,41(12):2146-2163
The previously reported oxytocin antagonist L-371,257 (2) has been modified at its acetylpiperidine terminus to incorporate various pyridine N-oxide groups. This modification has led to the identification of compounds with improved pharmacokinetics and excellent oral bioavailability. The pyridine N-oxide series is exemplified by L-372,662 (30), which possessed good potency in vitro (Ki = 4.1 nM, cloned human oxytocin receptor) and in vivo (intravenous AD50 = 0.71 mg/kg in the rat), excellent oral bioavailability (90% in the rat, 96% in the dog), good aqueous solubility (>8.5 mg/mL at pH 5.2) which should facilitate formulation for iv administration, and excellent selectivity against the human arginine vasopressin receptors. Incorporation of a 5-fluoro substituent on the central benzoyl ring of this class of oxytocin antagonists enhanced in vitro and in vivo potency but was detrimental to the pharmacokinetic profiles of these compounds. Although lipophilic substitution around the pyridine ring of compound 30 gave higher affinity in vitro, such substituents were a metabolic liability and caused shortfalls in vivo. Two approaches to prevent this metabolism, addition of a cyclic constraint and incorporation of trifluoromethyl groups, were examined. The former approach was ineffective because of metabolic hydroxylation on the constrained ring system, whereas the latter showed improvement in plasma pharmacokinetics in some cases. 相似文献
38.
EA Koller L Green JM Gertner M Bost SN Malozowski 《Canadian Metallurgical Quarterly》1998,83(7):2380-2383
A role for GH in the pathogenesis of diabetic retinopathy has long been postulated. Previous clinical studies, however, have been confounded by hyperglycemia. We have identified 2 cases of retinopathy associated with exogenous GH therapy in nondiabetic patients. Cases were identified through the MedWatch drug surveillance system of the U.S. Food and Drug Administration. Causality by concomitant medications was excluded by a search of the literature and the FDA data base. The first patient, an obese, 31-yr-old male with traumatic hypothalamic injury, presented with nonproliferative retinopathy and macular edema, resulting in decreased visual acuity (OD 20/40-1; OS count fingers), which required laser surgery. Human GH had been initiated at 0.009 mg/ kg.day, 14 months earlier, and titrated to 0.017 mg/kg.day. The second patient, a nonobese, 11-yr-old girl receiving GH for the management of short stature in Turner's Syndrome, presented with neovascularization. GH doses were 0.033 mg/kg.day for the first 17 months and 0.043 mg/ kg.day for the following 5 months. Cumulative laboratory and clinical observations suggest that GH and related peptides have a role in retinal pathology independent of the degree of glucose tolerance. 相似文献
39.
PURPOSE: To analyze the likelihood of perioperative transfusion using the data of the abstracted patient discharge records. MATERIAL AND METHODS: It was studied the data of the records of the pediatric patients in whom were done surgical procedures for 1996. The abstracted patient discharge records are codified according the ICD-9-CM codes. RESULTS: 1,166 pediatric patients were operated, of whom were transfused 25 (2.1%). The transfusion rate was higher in patients less than 3 years old, who were operated with three o more surgical procedures simultaneously, who were admitted newly after the admittance here studied, and patients operated of spine, dorsolumbar spine, pharynx, thorax and mediastinum, central nervous system, colon, vessels and hip. CONCLUSIONS: Given the variability of the transfusion rate, to know it will allow a better planning of the surgical transfusions, the policy of the hospital blood bank and to increase the information to patient about the risk of the elective surgery. 相似文献
40.