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141.
Phase I trial of intravenous carboplatin and cyclosporin A in refractory gynecologic cancer patients
SK Chambers CA Davis JT Chambers PE Schwartz MI Lorber RE Hschumacher 《Canadian Metallurgical Quarterly》1996,2(10):1699-1704
Our objective was to determine the maximum tolerated dose of cyclosporin A (CsA) delivered as a loading dose (LD) and continuous i.v. infusion (CI) in combination with carboplatin in patients with refractory gynecologic cancers. Twenty-nine heavily pretreated patients (25 ovarian epithelial, 2 cervical, and 2 endometrial carcinomas) received 113 cycles of CsA and carboplatin from September 1989 to September 1991. Twenty-four of these 29 carcinomas were strictly defined to be platinum resistant. CsA was administered as a LD escalated from 6 to 10 mg/kg followed by a 24-h CI from 2.5 to 14.5 mg/kg/day. Carboplatin was targeted to an area under the time versus concentration curve (AUC) of 6 mg/ml x min and was not dose escalated. Whole-blood CsA concentrations (fluorescence polarization immunoassay) at the maximum tolerated dose (10 mg/kg LD, 14.5 mg/kg/day CI) ranged from 2.4 to 3.0 microgram/ml over 12 h. Estimated median carboplatin AUC, based on calculated carboplatin clearance, was 7.9 mg/ml x min. The dose-limiting toxicity of the combination of CsA and carboplatin was grade 4 thrombocytopenia. Grade 3 or 4 thrombocytopenia occurred in 35% of the patients, which could be explained by the effects of carboplatin (AUC of 6 mg/ml x min) alone. Overall, neutropenia occurred in 24% of the patients and anemia in 17% of the patients. Grade 3 or 4 nausea or vomiting was noted in 10 and 14% of the patients, respectively. Grade 3 hypertension during CsA administration occurred in 14% of the patients. No grade 3 or 4 nephrotoxicity was seen in this trial. Three objective responses were noted: one complete response (11 months) and one partial response (5 months), both in potentially platinum-sensitive patients with platinum-free intervals of only 9 months each. One platinum-resistant patient had a partial response for 21 months. Five additional patients experienced >75% reduction of CA-125 or a return to a normal CA-125 titer. We concluded that whole-blood CsA concentrations of >3.0 microgram/ml (as seen when CsA is used as a modulator of multidrug resistance) were not achievable in this combination with carboplatin in this population of heavily pretreated gynecologic cancer patients. However, because CsA is used in this trial as a chemosensitizer in platinum-sensitive tumors and as a chemomodulator of platinum resistance, we targeted a CsA concentration of >1.0 microgram/ml, which was achieved. The CsA dose recommended for a Phase II trial of this combination is 10 mg/kg LD and 11.6 mg/kg/day CI, which results in blood CsA concentrations ranging from 1.2 to 1.3 microgram/ml over 12 h. Responses in this population of refractory gynecologic cancer patients are unusual, and these encouraging results form the basis for a Phase II trial of this combination. 相似文献
142.
The influence of anti-IGF-1 and anti-transforming growth factor beta (TGF-beta) neutralizing antibodies on preadipocyte differentiation and secretion of IGFBPs was examined in serum free porcine stromal-vascular cultures. Cultures were stained for morphological analysis and conditioned media were collected for: TGF-beta determination by ELISA, IGF-1 by RIA, and IGFBP analysis by ligand blotting. After 6 d of treatment, anti-TGF-beta increased fat proportions by 2.7 fold compared to controls. Anti-IGF-1 decreased fat cell proportions by 14-fold. Anti-TGF-beta increased concentrations of IGF-1 5.8-fold and IGFBP-2 and IGFBP-3 by 8- and 7-fold in conditioned media whereas IGFBP-4 decreased 5-fold. Anti-IGF-1 increased concentrations of IGFBP-2 and 3 by 9- and 35-fold, respectively. TGF-beta increased concentrations of IGFBP-1, 2 and 3 by 3-fold, 18-fold and 3-fold, respectively, after 9 d in culture (6 d of treatment). There was no change in TGF-beta levels in anti-IGF-1 treated cultures compared to controls. Control antibodies and negative controls had no effect. These results provide evidence that endogenously produced IGF-1 and TGF-beta has a major influence on preadipocyte differentiation in serum free media by modulating IGFBP production/secretion. 相似文献
143.
Neural correlates of attention and arousal: insights from electrophysiology, functional neuroimaging and psychopharmacology 总被引:1,自引:0,他引:1
JT Coull 《Canadian Metallurgical Quarterly》1998,55(4):343-361
Attention and arousal are multi-dimensional psychological processes, which interact closely with one another. The neural substrates of attention, as well as the interaction between arousal and attention, are discussed in this review. After a brief discussion of psychological and neuropsychological theories of attention, event-related potential correlates of attention are discussed. Essentially, attention acts to modulate stimulus-induced electrical potentials (N100/P100, P300, N400), rather than generating any unique potentials of its own. Functional neuroimaging studies of attentional orienting, selective attention, divided attention and sustained attention (and its inter-dependence on underlying levels of arousal) are then reviewed. A distinction is drawn between the brain areas which are crucially involved in the top-down modulation of attention (the 'sources' of attention) and those sensory-association areas whose activity is modulated by attention (the 'sites' of attentional expression). Frontal and parietal (usually right-lateralised) cortices and thalamus are most often associated with the source of attentional modulation. Also, the use of functional neuroimaging to test explicit hypotheses about psychological theories of attention is emphasised. These experimental paradigms form the basis for a 'new generation' of functional imaging studies which exploit the dynamic aspect of imaging and demonstrate how it can be used as more than just a 'brain mapping' device. Finally, a review of psychopharmacological studies in healthy human volunteers outlines the contributions of the noradrenergic, cholinergic and dopaminergic neurotransmitter systems to the neurochemical modulation of human attention and arousal. While, noradrenergic and cholinergic systems are involved in 'low-level' aspects of attention (e.g. attentional orienting), the dopaminergic system is associated with more 'executive' aspects of attention such as attentional set-shifting or working memory. 相似文献
144.
A 23 year old man with no history of neurological or psychiatric illness ingested three weekly 228 mg doses of mefloquine base (250 mg salt) as malaria prophylaxis while in India. He experienced an increasingly severe adverse reaction after each dose, including symptoms of paranoia, hallucinations, and suicidal ideation. The man discontinued mefloquine and continued malaria prophylaxis with chloroquine. Shortly after the first 300 mg dose of chloroquine base (500 mg chloroquine phosphate salt), symptoms acutely intensified and became debilitating. Severe symptoms persisted for 12 months following the discontinuation of both antimalarial drugs. 相似文献
145.
DJ Brick MJ Brumlik JT Buckley JX Cao PC Davies S Misra TJ Tranbarger C Upton 《Canadian Metallurgical Quarterly》1995,377(3):475-480
We have noted a striking similarity between the sequences of proteins in a novel family of lipases we recently reported [Upton, C. and Buckley, J. T. (1995) Trends Biol. Sci. 20, 178-9] and more than 120 sequences from the database of Expressed Sequence Tags (dbEST) which correspond to at least 30 unique genes from arabidopsis, rice and maize. A cDNA (Arab-1) corresponding to one of these sequences was isolated, sequenced and translated. There was significant similarity to sequences in the new lipase family over the entire open reading frame of Arab-1 and when expressed in E. coli, the gene product was lipolytic. Arab-1 and genes for some of the other plant proteins appear to be differentially expressed. They may play a role in the regulation of lipid metabolism during plant development. 相似文献
146.
The effects of chronic administration of [D-Pen2, D-Pen5]enkephalin and [D-Ala2, Glu4]deltorphin II, the selective agonists of the delta 1- and delta 2-opioid receptors, on the binding of [3H]MK-801, a noncompetitive antagonist of the N-methyl-D-aspartate receptor, were determined in several brain regions of the mouse. Male Swiss-Webster mice were injected intracerebroventricularly (i.c.v.) with [D-Pen2, D-Pen5]enkephalin or [D-Ala2, Glu4]deltorphin II (20 micrograms/mouse) twice a day for 4 days. Vehicle injected mice served as controls. Previously we have shown that the above treatment results in the development of tolerance to their analgesic activity. The binding of [3H]MK-801 was determined in brain regions (cortex, midbrain, pons and medulla, hippocampus, striatum, hypothalamus and amygdala). At 5 nM-concentration, the binding of [3H]MK-801 was increased in cerebral cortex, hippocampus, and pons and medulla of [D-Pen2, D-Pen5]enkephalin treated mice. In [D-Ala2, Glu4]deltorphin II treated mice, the binding of [3H]MK-801 was increased in cerebral cortex and hippocampus. The changes in the binding were due to increases in the Bmax value of [3H]MK-801. It is concluded that tolerance to delta 1- and delta 2-opioid receptor agonists is associated with up-regulation of brain N-methyl-D-aspartate receptors, however, some brain areas affected differ with the two treatments. The results are consistent with the recent observation from this laboratory that N-methyl-D-aspartate receptors antagonists block tolerance to the analgesic action of delta 1- and delta 2-opioid receptor agonists. 相似文献
147.
JF Ascaso R Lorente A Merchante JT Real A Priego R Carmena 《Canadian Metallurgical Quarterly》1997,80(11):1484-1487
The minimum model modified by the administration of insulin provides an objective and relatively easily measured index of peripheral sensitivity to insulin which was significantly lower (p <0.02) in familial combined hyperlipidemia (FCH) with ischemic heart disease (IHD) than in FCH without IHD and in control subjects (1.2 +/- 0.6, 1.9 +/- 1.0, 2.9 +/- 1.2 x 10(-4) mU/L/ min, respectively). In patients with FCH, insulin resistance explains, at least in part, their metabolic alterations (hypertension, abnormal glucose tolerance, hyperinsulinemia) and elevated IHD. 相似文献
148.
The standard enthalpy of ionization of six titratable histidines in horse metaquomyoglobin was determined by repeating proton NMR titrations as a function of temperature and using the van't Hoff relationship. It was found that deltaH degrees varies between 16 and 37 kJ mol(-1) in the protein, compared with a value of 29 kJ mol(-1) in free histidine. The standard entropy change was evaluated by combining the enthalpy and free energy changes derived from the pKa values. Although the entropy change could not be precisely and accurately obtained by this method, it could be established that it spans a wide range, from -60 to 0 J K(-1) mol(-1), about the value of -23 J K(-1) mol(-1) for the free histidine. The entropy change was used within the framework of enthalpy-entropy compensation to partition the solvation component from the standard thermodynamic quantities for each of the titrating residues. It was shown that the partitioning of the values in the protein is not readily understood in terms of solvent accessibility or electrostatic interactions. The contribution of solvation effects to the temperature response appeared to be significant only in the case of His-119 and His-48. The standard quantities were also used to explore the energetics of proton binding in the native state at temperatures below the onset of thermal denaturation. 相似文献
149.
JT Sandlund T Fonseca T Leimig L Verissimo R Ribeiro V Lira CW Berard J Sixbey WM Crist L Mao G Chen CH Pui M Heim F Pedrosa 《Canadian Metallurgical Quarterly》1997,11(5):743-746
The purpose of this paper was to define the histologic distribution, clinical features, and treatment response of childhood non-Hodgkin lymphoma (NHL) in northeastern Brazil. We reviewed medical records and histopathologic studies of 98 children treated for NHL from 1980 to 1987 at a major pediatric cancer center in Recife, Brazil. Treatment outcome was evaluated in relation to tumor burden (stage and serum LDH) and type of therapy (LSA2L2 vs other multiagent chemotherapy). There was a striking predominance of the small noncleaved cell (Burkitt) subtype, which occurred in 92 of the 98 children and adolescents diagnosed with NHL. Subsequent analyses focused on these patients. The majority (n = 84) had advanced (stage III/IV) disease at diagnosis. The abdomen was the most common site of disease (84 cases); jaw involvement was rare (three cases). Five-year event-free survival (excluding treatment refusals) was significantly better for patients with limited vs advanced stage disease (75 +/- 14% vs 42 +/- 6%; P < 0.04). Elevated serum LDH (>500 U/l) was associated with a poorer outcome (P = 0.008). The type of chemotherapy did not affect EFS (P = 0.95). Only 39% of patients are long-term survivors, reflecting the high rate of septic deaths (25% of patients) and parental refusal/abandonment of therapy (10%). Epstein-Barr virus (EBV) was detected in tumor cells from eight of the 11 cases studied. In clinical presentation, these cases resemble sporadic Burkitt lymphoma, yet in their apparent responsiveness to LSA2L2 therapy and association with EBV, they do not. Childhood NHL in northeastern Brazil is predominantly of the Burkitt subtype, and is associated with clinical features that appear to distinguish it from the endemic and sporadic forms of this tumor. These cases may represent a third or intermediate subtype of Burkitt lymphoma. 相似文献
150.
VM Factor CY Kao E Santoni-Rugiu JT Woitach MR Jensen SS Thorgeirsson 《Canadian Metallurgical Quarterly》1997,57(11):2089-2095
Transforming growth factor beta-1 (TGF-beta1) is a potent inhibitor of hepatocyte growth both in vivo and in vitro. In this study, we analyzed the effects of TGF-beta1 on both naturally occurring and diethylnitrosamine-induced hepatocarcinogenesis using single transgenic TGF-beta1 and double transgenic c-myc/TGF-beta1 mice in which the expression of both transgenes was targeted to the liver. Hepatocellular tumors developed spontaneously in 59% (10 of 17) of the TGF-beta1 mice by 16-18 months of age. Coexpression of TGF-beta1 and c-myc transgenes in the liver accelerated hepatic tumor growth in both the presence and absence of carcinogenic treatment. Moreover, diethylnitrosamine-initiated tumors in the c-myc/TGF-beta1 mice showed a high rate of malignant conversion associated with a reduced expression or lack of TGF-beta receptor type II. The results suggest that overexpression of TGF-beta1 may contribute to liver carcinogenesis and that loss of TGF-beta receptor type II transduced inhibitory growth signals and up-regulation of c-myc are critical steps in liver tumor progression. 相似文献