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891.
A phase I study of TNP-470 administered to patients with advanced squamous cell cancer of the cervix
AP Kudelka T Levy CF Verschraegen CL Edwards S Piamsomboon W Termrungruanglert RS Freedman AL Kaplan DG Kieback CA Meyers KA Jaeckle E Loyer M Steger R Mante G Mavligit A Killian RA Tang JU Gutterman JJ Kavanagh 《Canadian Metallurgical Quarterly》1997,3(9):1501-1505
A Phase I study of the novel angiogenesis inhibitor TNP-470 was performed. Patients with inoperable recurring or metastatic squamous cell cancer of the cervix with evaluable disease, no coagulopathy, and adequate renal, hepatic, and hematological function were eligible. One course of treatment consisted of an i.v. infusion of TNP-470 over 60 min every other day for 28 days, followed by a 14-day rest period. The starting dose was 9.3 mg/m2. Eighteen evaluable patients were treated, with a median age of 48 years (range 27-55) and performance status Zubrod 1 (range 0-2). Grade 3 neurotoxicities consisting of weakness, nystagmus, diplopia, and ataxia were encountered in two patients receiving the 71.2 mg/m2 dose. An intermediate dose level of 60 mg/m2 was evaluated and found to be well tolerated by three patients. Only one patient experienced grade 3 nausea on the 60 mg/m2 dose level. No myelosuppression, retinal hemorrhage, weight loss, or significant alopecia were observed. One patient had a complete response, which continues for 26 months, and three patients with initially progressive disease stage had stable disease for 5, 7.7, and 19+ months. Other Phase I studies, including over 200 patients, were performed concurrently with this study. Based on this experience, the dose of TNP-470 recommended for further studies is 60 mg/m2 as a 60-min i.v. infusion every Monday, Wednesday, and Friday. Neurotoxicity was dose limiting, but appears to be reversible. Otherwise, the treatment was well tolerated. The drug may be active in squamous cell cancer of the cervix. Further studies of TNP-470 in squamous cell cancer of the cervix are warranted. 相似文献
892.
RS McCuskey J Nishida D McDonnell C Williams O Koldovsky 《Canadian Metallurgical Quarterly》1997,71(3):202-206
A Rehabilitation Information System was created in July 1993 in order to register war victims in need of physical rehabilitation all over Croatia. The system is currently operating and presented data covers the period from July 1991 to July 1995. Approximately 15,000 questionnaires had been completed and returned from medical institutions on in total 8589 disabled war victims in need of rehabilitation. People with severe disabilities comprised about 20% of all in need of rehabilitation. Those reported injured were 3.5 times more than those in need of physical rehabilitation. Most common types of injuries were fractures with a permanent disabling condition (3109 persons), peripheral nerve injuries (1213 persons) and amputations (956 persons). Traumatic brain injuries were registered for 594 and spinal cord injuries for 262 persons. Causes of injuries were explosive devices (such as mines, mortar shell shrapnel, etc.) in 37% of cases, bullets in 22%, accidents in 7%, other (such as fire, blast injuries, etc.) and unknown causes in 34%. 相似文献
893.
JR Burnett LJ Wilcox DE Telford SJ Kleinstiver PH Barrett RS Newton MW Huff 《Canadian Metallurgical Quarterly》1997,17(11):2589-2600
In the present studies, the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor atorvastatin was used to test the hypothesis that inhibition of cholesterol biosynthesis in vivo with a consequent reduction in the availability of hepatic cholesterol for lipoprotein synthesis, would (1) reduce very low density lipoprotein (VLDL) apolipoprotein B (apoB) secretion into the plasma, (2) reduce the conversion of VLDL apoB to LDL apoB, and (3) reduce LDL apoB direct synthesis. ApoB kinetic studies were carried out in six control miniature pigs and in six animals after 21 days of administration of atorvastatin (3 mg/kg per day). Pigs were fed a fat- (34% of calories; polyunsaturated to monounsaturated to saturated ratio, 1:1:1) and cholesterol- (400 mg/d cholesterol; 0.1%; 0.2 mg/kcal) containing pig chow-based diet. Atorvastatin treatment significantly reduced plasma total cholesterol, LDL cholesterol, total triglyceride, and VLDL triglyceride concentrations by 16%, 31%, 19%, and 28%, respectively (P < .01). Autologous 131I-VLDL, 125I-LDL, and [3H]leucine were injected simultaneously into each pig, and apoB kinetic data were analyzed using multicompartmental analysis (SAAM II). The VLDL apoB pool size decreased by 29% (0.46 versus 0.65 mg/kg; P = .002), which was entirely due to a 34% reduction in the VLDL apoB production rate (PR) (1.43 versus 2.19 mg/kg per hour; P = .027). The fractional catabolic rate (FCR) was unchanged. The LDL apoB pool size decreased by 30% (4.74 versus 6.75 mg/kg; P = .0004), which was due to a 22% reduction in the LDL apoB PR (0.236 versus 0.301 mg/kg per hour; P = .004), since the FCR was unchanged. The reduction in LDL apoB PR was primarily due to a 34% decrease in conversion of VLDL apoB to LDL apoB; however, this reduction was not statistically significant (P = .114). Hepatic apoB mRNA abundance quantitated by RNase protection assay was decreased by 13% in the atorvastatin-treated animals (P = .003). Hepatic and intestinal LDL receptor mRNA abundances were not affected. We conclude that inhibition of hepatic HMG-CoA reductase by atorvastatin reduces both VLDL and LDL apoB concentrations, primarily by decreasing apoB secretion into the plasma and not by an increase in hepatic LDL receptor expression. This decrease in apoB secretion may, in part, be due to a reduction in apoB mRNA abundance. 相似文献
894.
RS Kern BD Marshall TG Kuehnel J Mintz JL Hayden MJ Robertson MF Green 《Canadian Metallurgical Quarterly》1997,17(5):432-435
A total of 34 patients with advanced ovarian cancer, who relapsed 1-72 months after at least one first-line cisplatin-based chemotherapy protocol, were treated with carboplatin, 350 mg/m2 q 4 weeks, with the adjunct of primary prophylactic granulocyte colony stimulating factor (G-CSF; filgrastim), 300 or 480 microg daily, days 5-9. Over 90% of the anticipated dose of carboplatin could be administered. Partial response, defined as a decline in CA-125 of 50% or more on two consecutive samples, occurred in 42%, while 15% of patients achieved a complete response (no clinical signs of disease with normalization of CA-125). Survival from start of carboplatin treatment was 23 months. Myelosuppression was the most important toxicity with 35% of patients experiencing grade 4 thrombocytopenia of short duration. Grade 4 leucopenia occurred in only one patient. It is concluded that single-agent carboplatin, with the adjunct of prophylactic G-CSF, can be administered with adequate dose intensity, and is an effective and acceptable palliative treatment for patients with relapse after first-line cisplatin-based chemotherapy. 相似文献
895.
896.
OBJECTIVES: To explore the use of 99technetiumm-hexamethyl propylene amine oxime single photon computed tomography (HMPAO-SPECT) of the brain as a means of detecting nervous tissue damage in divers and to determine if there is any correlation between brain image and a diver's history of diving or decompression illness (DCI). METHODS: 28 commercial divers with a history of DCI, 26 divers with no history of DCI, and 19 non-diving controls were examined with brain HMPAO-SPECT. Results were classified by observer assessment as normal (I) or as a pattern variants (II-V). The brain images of a subgroup of these divers (n = 44) and the controls (n = 17) were further analysed with a first order texture analysis technique based on a grey level histogram. RESULTS: 15 of 54 commercial divers (28%) were visually assessed as having HMPAO-SPECT images outside normal limits compared with 15.8% in appropriately identified non-diver control subjects. 18% of divers with a history of DCI were classified as having a pattern different from the normal image compared with 38% with no history of DCI. No association was established between the presence of a pattern variant from the normal image and history of DCI, diving, or other previous possible neurological insult. On texture analysis of the brain images, divers had a significantly lower mean grey level (MGL) than non-divers. Divers with a history of DCI (n = 22) had a significantly lower MGL when compared with divers with no history of DCI (n = 22). Divers with > 14 years professional diving or > 100 decompression days a year had a significantly lower MGL value. CONCLUSIONS: Observer assessment of HMPAO-SPECT brain images can lead to disparity in results. Texture analysis of the brain images supplies both an objective and consistent method of measurement. A significant correlation was found between a low measure of MGL and a history of DCI. There was also an indication that diving itself had an effect on texture measurement, implying that it had caused subclinical nervous tissue damage. 相似文献
897.
E Aronica DW Dickson Y Kress JH Morrison RS Zukin 《Canadian Metallurgical Quarterly》1998,82(4):979-991
Alzheimer's disease is a progressive dementia characterized by a pronounced neurodegeneration in the entorhinal cortex, hippocampal CA1, and subiculum. Excitatory amino acid receptor-mediated excitotoxicity is postulated to play a role in the neurodegeneration in Alzheimer's disease. The present study investigated immunocytochemical localization of excitatory amino acid receptor subunits in the hippocampus of twelve Alzheimer's disease and eleven controls, matched for age, sex and post mortem interval. Immunocytochemistry with antibodies specific for glutamate receptors GluR1, GluR2(4) (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid), GluR5/6/7 (kainate) and NR1 (N-methyl-D-aspartate) receptor subunits demonstrated that virtually all projection neurons in all subfields contained subunits from each receptor class. However, regional differences in immunoreactivity were apparent in Alzheimer's disease vs normal human brain. In the vulnerable regions (i.e. CA1) immunolabelling of GluR1, GluR2(4), GluR5/6/7 and NR1 was reduced, presumably due to cell loss. In contrast, GluR2(4) immunolabelling appeared to be increased in the inner portion of the molecular layer of the dentate gyrus. In addition to cellular labelling, GluR1, GluR2(4) and NR1 immunolabelling revealed a novel pathological structure in 12 of 12 Alzheimer's disease, but none of the control brains. The lesions were juxtacellular clusters of granular immunoreactivity in the neuropil of the pyramidal cell layer. Ultrastructural analysis revealed these to be cellular processes containing dense vesicles and flocculent material with immunolabelling localized to plasma and vesicular membranes. They were not specifically associated with amyloid fibrils and did not contain paired helical filaments and they were also distinct from granulovacuolar degeneration. Several structures contained Hirano body filaments indicating that the dystrophic processes were most likely dendritic in origin. Additional studies are needed to determine the pathogenesis of these lesions, which could provide an additional index of dendritic deterioration in Alzheimer's disease. 相似文献
898.
OBJECTIVE: To determine if a structured encounter form for well-child care improves documentation of well-child care. DESIGN: Retrospective medical record review of a before-and-after trial. SETTING: Family practice residency clinic serving a primarily low-socioeconomic urban population. PATIENTS: Children younger than 6 years receiving well-child care visits. INTERVENTION: Detailed checklists were developed and implemented in 1994 for each of 12 well-child examinations for the assessment of children aged 2 weeks to 5 years based on recommendations from the American Academy of Pediatrics and the US Preventive Services Task Force. MAIN OUTCOME MEASURES: Documentation of multiple aspects of well-child care, including developmental assessment, safety and nutrition counseling, and laboratory tests for 6-month periods in 1993 and 1994, before and after implementation of the structured encounter form. RESULTS: A total of 842 well-child visits were reviewed. Documentation improved significantly with the use of the encounter form for 19 of the 23 aspects of well-child care that were studied. Screening test rates were less than optimal despite the encounter form. CONCLUSIONS: The structured encounter form was very effective in improving documentation of almost all aspects of well-child care. However, effective communication is needed among physicians, nurses, and parents to ensure optimal screening test rates. 相似文献
899.
Myristoyl-CoA:protein N-myristoyltransferase (NMT) is an essential eukaryotic enzyme that catalyzes the cotranslational transfer of myristate to the NH2-terminal glycine residue of a number of important proteins of diverse function. Human NMT (hNMT) activity was found to be activated by L-histidine in a concentration-dependent manner. In contrast, two structural analogues of L-histidine, L-histidinol and histamine, inhibited hNMT activity in a noncompetitive manner with half-maximal inhibitions of 18 and 1.5 mM, respectively. The inhibition of hNMT activity by L-histidinol was reversed by a 2-fold molar excess of L-histidine, suggesting that L-histidine and L-histidinol were competing for a common site on NMT. Kinetic data indicated that whereas L-histidine enhanced the Vmax, both L-histidinol and histamine decreased the Vmax; none of these compounds altered the Km. Our studies suggest that L-histidine and its analogues may be interacting with His-293, involved in myristoyl-CoA transfer, rather than His-218, and implicated in the transfer of myristoyl-CoA to the peptide substrates. Site-directed mutagenesis of His-293, Val-291, and Glu-290 resulted in proteins with no measurable NMT activity. The most conserved region in the catalytic domain EEVEH (289-293) is critical for the myristoyl-CoA transfer in the NMT-catalyzed reactions. This region will be useful for the design of regulators of NMT function. 相似文献
900.
SE Maslanka JW Tappero BD Plikaytis RS Brumberg JK Dykes LL Gheesling KB Donaldson A Schuchat J Pullman M Jones J Bushmaker GM Carlone 《Canadian Metallurgical Quarterly》1998,66(6):2453-2459
Neisseria meningitidis serogroup C bactericidal titers and class-specific enzyme-linked immunosorbent assay (ELISA) antibody concentrations were measured in sera from 173 children (1 to 5 years old) before and 6 weeks and 7 months following vaccination with a quadrivalent (A/C/Y/W-135) polysaccharide vaccine. The immune responses of the children were compared with those of 40 adults 6 weeks postvaccination. Both bactericidal titers and ELISA antibody concentrations were significantly higher in the adults than in the children (P < 0.05). In addition, the ratio of immunoglobulin G (IgG) to IgM was higher in the children than in the adults. With an ELISA total antibody concentration of >/=2 microg/ml used as a measure of seroconversion, >/=84% of the individuals from each age group responded to the serogroup C polysaccharide. However, with a >/=4-fold-increase in bactericidal titer used, only 18% of 1-year-olds, 32% of 2-year-olds, and 50 to 60% of 3-, 4-, and 5-year-olds seroconverted. The ELISA results suggest that >50% of all children retained >/=2 microg of total antibody per ml at 7 months postimmunization. However, the bactericidal titers suggest that <10% of children <4 years old retained a >/=4-fold increase at 7 months following vaccination. Of particular note, 59 of 79 sera (75%) from the 1- and 2-year-olds had high ELISA antibody concentrations (2 to 20 microg/ml) with no associated bactericidal titer (<1:8). Discordant results between bactericidal titers and ELISA antibody concentrations were not explained by the presence of IgA blocking antibody or relative levels of IgG and IgM. The bactericidal results show age-dependent differences in the production and retention of antibody in young children immunized with serogroup C polysaccharide; these differences are not evident with the ELISA data. 相似文献