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121.
122.
It is important to monitor the early stages of postoperative wound repair in order to identify those problems associated with impaired healing. Many of the crucial cellular responses of early wound healing, such as inflammatory infiltration, angiogenesis and re-epithelialization, are made possible through the action of matrix metalloproteinases (MMPs). Expression of MMP-2 and MMP-9 is elevated in acute wounds, and still greater levels are found in chronic wounds, indicating that uncontrolled proteolysis is a characteristic of retarded healing. Therefore, comparative measurements of MMPs may be used to monitor the progression of early wound healing. To investigate this, wound fluids and sera were collected from mastectomy and colectomy patients throughout early stages of repair, and the temporal expression profile established. Wounds which were healing were expressed maximal levels of MMP-9 at 24 h, followed by a significant decline by 48 h. Persistent elevation of MMP-9 expression was associated with infected and chronic wounds, and was identified in postoperative wounds by the absence of the significant decline between 24 and 48 h. Measurement of MMP-9 in postoperative wound fluids, therefore, provides an early indicator of impaired healing, which may be evaluated non-invasively within 48 h of closure. 相似文献
123.
JF Price 《Canadian Metallurgical Quarterly》1997,27(9):1004-1006
OBJECTIVE: To describe a rare case of right renal agenesia and left pelvic ectopy. To our knowledge, only 10 such cases have been reported in the world literature. METHODS: A 76-year-old male patient who consulted for irritative prostatic syndrome is described. Patient evaluation included IVP and CT. RESULTS: IVP revealed the absence of the right kidney in addition to an anomalous position of the left kidney. The foregoing findings were confirmed by CT. CONCLUSION: This uncommon congenital anomaly is essentially asymptomatic and is generally diagnosed in infants through its complications. In the case described herein, however, this anomaly had been incidentally detected during IVP and CT assessment of a 76-year-old patient who had consulted for irritative prostatic syndrome. 相似文献
124.
R Hajdu R Thompson JG Sundelof BA Pelak FA Bouffard JF Dropinski H Kropp 《Canadian Metallurgical Quarterly》1997,41(11):2339-2344
MK-0991 (L-743,872) is a potent antifungal agent featuring long half-life pharmacokinetics. The pharmacokinetics of MK-0991 administered intravenously to mice, rats, rhesus monkeys, and chimpanzees is presented. Unique to MK-0991 is its consistent cross-species performance. The range of values for the pharmacokinetic parameters were as follows: clearance, 0.26 to 0.51 ml/min/kg; half-life, 5.2 to 7.6 h; and distributive volume, 0.11 to 0.27 liters/kg. The level of protein binding of MK-0991 was determined to be 96% in mouse and human serum. The compound exhibited high affinities for human serum albumin and at least two lipid components. The rationale for the selection of MK-0991 as a drug development candidate was based on its two- to threefold superior pharmacokinetic performance in chimpanzees over the performance of an otherwise equivalent analog, L-733,560. Once-daily dosing for MK-0991 is indicated by a graphical comparison of levels in the circulations of chimpanzees and mice. In a study of the pharmacokinetics of MK-0991 in mouse tissue, the organs were assayed following intraperitoneal administration. The area under the concentration-versus-time curves (AUC) segregated the tissues into three exposure categories relative to plasma. The tissues with greater exposure than that for plasma were liver (16 times), kidney (3 times), and large intestine (2 times). The exposure for small intestine, lung, and spleen were equivalent to that for plasma. Organs with lower levels of exposure were the heart (0.3 times that for plasma), thigh (0.2 times), and brain (0.06 times). Kinetically, drug was cleared more slowly from all tissues than from plasma, indicating that terminal-phase equilibrium had not been achieved by 24 h. Thus, some measure of accumulation is predicted for all tissues. Single daily doses of MK-0991 should provide adequate systemic levels of fungicidal activity as a result of its long half-life pharmacokinetics, wide distribution, and slowly accumulating concentrations in tissue. 相似文献
125.
JA van Dorst CJ van Heusden JM Tikkanen JP Kamerling JF Vliegenthart 《Canadian Metallurgical Quarterly》1997,297(3):209-227
Seven analogues of the trisaccharide beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-->O)(CH 2)7CH3 have been synthesized as potential substrates for glycosyltransferases involved in the chain-termination of N-acetyllactosamine-type N-glycans. These compounds include: 3-O-methyl-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp -(1-->O) (CH2)7CH3, 3-deoxy-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1 -->O) (CH2)7CH3, 3-deoxy-3-fluoro-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-M anp- (1-->O)(CH2)7Ch3, 3-amino-3-deoxy-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Ma np- (1-->O)(CH2)7CH3, beta-D-Gulp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-- >O)(CH2)7CH3, beta-L-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-->O)(CH 2)7CH3, and alpha-L-Altp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1- ->O) (CH2)7CH3. All trisaccharides were obtained by condensation of suitably modified glycosyl donors based on imidates or thioglycosides with the same disaccharide acceptor, octyl 3,4,6-tri-O-benzyl-2-O-(3,6-di-O-benzyl-2-deoxy-2-phthalimido-beta-D- glucopyranosyl)-alpha-D-mannopyranoside, followed by deprotection. 相似文献
126.
JF Linn M Lango S Halachmi MP Schoenberg D Sidransky 《Canadian Metallurgical Quarterly》1997,74(6):625-629
We performed microsatellite analysis and tested telomerase activity in paired tissue and urine of bladder cancer patients from frozen archived samples. DNA obtained from microdissected tumor and urine sediment was analyzed and compared to peripheral lymphocytes for microsatellite alterations (loss of heterozygosity [LOH] or instability) using a panel of 20 microsatellite markers in 15 patients with transitional or squamous cell carcinoma of the urinary tract. Additionally, telomerase activity was determined in 12 microdissected tumor specimens and corresponding frozen urine pellets. Tumor cell DNA was detected by microsatellite analysis (LOH or shift) in at least one marker in 14/15 microdissected tumor specimens and in 13/15 DNA samples obtained from urine sediments. Telomerase activity was present in 11/12 tumor samples but could not be detected in any of the corresponding urine sediments. Frozen archived urine samples are useful for retrospective studies utilizing microsatellite analysis or other PCR-based approaches after DNA extraction. However, the evaluation of telomerase protein activity in stored urine samples appears to be unsuitable. 相似文献
127.
BS Kendrick BS Chang T Arakawa B Peterson TW Randolph MC Manning JF Carpenter 《Canadian Metallurgical Quarterly》1997,94(22):11917-11922
Understanding the mechanism for sucrose-induced protein stabilization is important in many diverse fields, ranging from biochemistry and environmental physiology to pharmaceutical science. Timasheff and Lee [Lee, J. C. & Timasheff, S. N. (1981) J. Biol. Chem. 256, 7193-7201] have established that thermodynamic stabilization of proteins by sucrose is due to preferential exclusion of the sugar from the protein's surface, which increases protein chemical potential. The current study measures the preferential exclusion of 1 M sucrose from a protein drug, recombinant interleukin 1 receptor antagonist (rhIL-1ra). It is proposed that the degree of preferential exclusion and increase in chemical potential are directly proportional to the protein surface area and that, hence, the system will favor the protein state with the smallest surface area. This mechanism explains the observed sucrose-induced restriction of rhIL-1ra conformational fluctuations, which were studied by hydrogen-deuterium exchange and cysteine reactivity measurements. Furthermore, infrared spectroscopy of rhlL-1ra suggested that a more ordered native conformation is induced by sucrose. Electron paramagnetic resonance spectroscopy demonstrated that in the presence of sucrose, spin-labeled cysteine 116 becomes more buried in the protein's interior and that the hydrodynamic diameter of the protein is reduced. The preferential exclusion of sucrose from the protein and the resulting shift in the equilibrium between protein states toward the most compact conformation account for sucrose-induced effects on rhIL-1ra. 相似文献
128.
BD Cohen JF Bowley PJ Sheridan 《Canadian Metallurgical Quarterly》1997,18(2):158, 160, 162-158, 160, 164
Three postgraduate prosthodontic students served as clinicians/evaluators in a study rating their preferences for three different diamond cutting instruments from three manufacturers. Each evaluator prepared the axial walls of complete veneer crowns on extracted molar teeth and then ranked their preference of the instruments. To prepare nine teeth, each of the three instruments was used in random order and without knowledge of the specific manufacturer. The methodology for analyzing the evaluators' preferences and the results are discussed. 相似文献
129.
JF Watchko MJ Daood GC Sieck JJ LaBella BT Ameredes AP Koretsky B Wieringa 《Canadian Metallurgical Quarterly》1997,82(5):1416-1423
Creatine kinase (CK) is an enzyme central to cellular high-energy phosphate metabolism in muscle. To characterize the physiological role of CK in respiratory muscle during dynamic contractions, we compared the force-velocity relationships, power, and work output characteristics of the diaphragm (Dia) from mice with combined myofibrillar and sarcomeric mitochondrial CK deficiency (CK[-/-]) with CK-sufficient controls (Ctl). Maximum velocity of shortening was significantly lower in CK[-/-] Dia (14.1 +/- 0.9 Lo/s, where Lo is optimal fiber length) compared with Ctl Dia (17.5 +/- 1.1 Lo/s) (P < 0.01). Maximum power was obtained at 0.4-0.5 tetanic force in both groups; absolute maximum power (2,293 +/- 138 W/m2) and work (201 +/- 9 J/m2) were lower in CK[-/-] Dia compared with Ctl Dia (2,744 +/- 146 W/m2 and 284 +/- 26 J/m2, respectively) (P < 0.05). The ability of CK[-/-] Dia to sustain shortening during repetitive isotonic activation (75 Hz, 330-ms duration repeated each second at 0.4 tetanic force load) was markedly impaired, with CK[-/-] Dia power and work declining to zero by 37 +/- 4 s, compared with 61 +/- 5 s in Ctl Dia. We conclude that combined myofibrillar and sarcomeric mitochondrial CK deficiency profoundly impairs Dia power and work output, underscoring the functional importance of CK during dynamic contractions in skeletal muscle. 相似文献
130.
MG Seves MJ Brito S Lamy PV Luiz G Bastos M Faleiro J Batista JF De Sousa 《Canadian Metallurgical Quarterly》1998,11(7):631-634
Hormone-refractory prostate cancer (HRPC) patients often have nonmeasurable disease. In such patients, predictive biomarkers other than tumor response may be required to compare therapeutic effects. We examined the predictive value for survival of various clinical and laboratory parameters, including prostate-specific antigen (PSA), in HRPC patients treated with suramin. Data from 103 HRPC patients were analyzed using various survival analyses, the likelihood ratio approach, and logistic regression analyses. When pretreatment factors, percentage decrease in PSA at 4 weeks from start of treatment (deltaPSA), and updated survival data were fit by a multivariate Cox proportional hazards model, acid phosphatase, lactate dehydrogenase, and deltaPSA were significant, with risk ratios close to 1. There was a decrease in likelihood ratio with increasing APSA. A logistic regression model was developed to predict the probability of <1 year of survival from the start of treatment. Hemoglobin and deltaPSA were found to be significant variables. However, in view of the complexities involving the relationship between PSA expression and prostate cancer growth and possible selective effect of treatment on PSA, further prospective testing is necessary. Therefore, deltaPSA cannot necessarily be used as a biomarker for survival response in individual patients during the evaluation of the therapeutic response of HRPC to new antineoplastic drugs. 相似文献