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J J Crowley

Publications and source records attributed to J J Crowley.

At least 109 records · Page 6Linked to original sources
PubMed1991

Interpretation of survival data in clinical trials.

The results of therapeutic interventions can often be best described through the distribution of times to some event. The most obvious example of this is actual survival (time to death) and the methods used in the analysis of "time to event" data are broadly referred to as "survival analysis." However, survival analysis really refers to the evaluation of time to any definable event. The goals of survival analysis are to estimate the "time to event" distribution for a defined group of patients and to compare the experience of different groups of patients. In the case of a chronic disease like cancer, the analysis is complicated because the event of interest may not yet have taken place or the patient may have been lost to follow-up. Here we review the standard techniques used in the analysis of survival data and discuss important related issues.

Clinical Trials as Topic↗
PubMed1990

Comparison of etoposide and cisplatin with bis-chloro-ethylnitrosourea, thiotepa, vincristine, and cyclophosphamide for salvage treatment in small cell lung cancer. A Southwest Oncology Group Study.

Small cell lung cancer patients who failed primary systemic therapy or who failed after response were randomly assigned to salvage treatment with etoposide (VP-16) and cisplatin (CDDP) or bis-chloro-ethylnitrosourea, thiotepa, vincristine, and cyclophosphamide (BTOC). Good risk patients were those who had tolerated prior chemotherapy well, those who had not had prior radiation therapy, and those who were 65 years of age or younger. Patients with a history of poor tolerance, prior radiation therapy, or those who were older than 65 years of age were classified as poor risk. Forty-five patients were randomized to the BTOC regimen and 58 to the VP-16/CDDP regimen. The overall remission rate was 13% (13 of 103 patients). Good risk patients treated with the BTOC regimen had a remission rate of 27% (three of 11 patients), which was the same rate as patients treated with the VP-16/CDDP regimen (three of 11 patients). Poor risk patients had remission rates of 9% (three of 34 patients) with the BTOC regimen and 9% (four of 47 patients) with the VP-16/CDDP regimen. The median survival time from the start of therapy was 16 weeks for all patients. BTOC good risk patients had a median survival time of 10 weeks, as compared with 14 weeks for poor risk patients. VP-16/CDDP good risk patients had a median survival time of 35 weeks, as compared with 12 weeks for poor risk patients. Although based on small numbers, the advantage in survival time for good risk patients treated with VP-16/CDDP over those treated with BTOC is statistically significant. Prior exposure to VP-16 did not influence the outcome of patients treated with VP-16/CDDP. Both regimens produced moderate toxicity, but were generally well tolerated. It was concluded that VP-16/CDDP may be a useful salvage treatment for good risk patients, despite its limited remission rate. Also, it was found that BTOC has no value for patients in this setting and that neither regimen helps patients who are poor risk.

Adult↗
PubMed1990

A-phase II study of intravenous 6-thioguanine (NSC-752) in multiple myeloma. A Southwest Oncology Group study.

Thirty-three patients with relapsing or refractory multiple myeloma were treated with 6-Thioguanine (6TG) at a dose of 1 g/M2, with therapy given over four hours every three weeks. The major toxicity seen was myelotoxicity; thrombocytopenia was more commonly noted than neutropenia. One patient achieved a PR, two were clinically improved. 6TG in this short infusion schedule proved to be myelotoxic, but demonstrated little activity in previously treated myeloma patients.

Drug Evaluation↗
PubMed1990

Phase II study of fludarabine phosphate in multiple myeloma. A Southwest Oncology Group study.

Thirty-one patients with multiple myeloma refractory to therapy or relapsing after response to initial therapy were treated with Fludarabine Phosphate utilizing a daily intravenous schedule for five consecutive days. There were no objective responses seen and only one patient showed clinical improvement. Myelosuppression manifest as leucopenia and granulocytopenia was the primary toxicity seen. Fludarabine Phosphate is inactive in previously treated myeloma patients when given by the daily intravenous route.

Adult↗
PubMed1990

The incidence of a new human cross-reactive idiotype linked to subgroup VHIII heavy chains.

Cross-reactive idiotypes (CRI) on human rheumatoid factors (RF), which are identified by murine monoclonal antibodies (mAb), have proved useful in defining both the incidence and the structural characteristics of these autoantibodies. In this study, a new murine anti-idiotypic reagent, mAb B6, has been used to identify and define the expression of a distinct heavy chain CRI. The B6 CRI was found on 20% of monoclonal IgM (16 of 81), but on only 5% of monoclonal IgA (1 of 20) and on no monoclonal IgG. In addition, this CRI was expressed exclusively on a subset of Ig derived from the VHIII protein variable region subgroup. In immunoblotting experiments, the mAb B6 bound directly to the heavy (H) chains of CRI positive proteins. The B6 CRI was found frequently on monoclonal IgM-RF molecules, and the mAb B6 could inhibit the binding of the RF to its IgG antigen. It was also demonstrated that Staphylococcus aureus protein A (SpA), which has recently been shown to bind to the F(ab) region of VHIII molecules, could block the interaction of some B6 CRI positive IgM to the anti-CRI. These experiments suggest that the B6 CRI is a marker for one or a few VHIII genes and that it is expressed commonly on IgM paraproteins, many of which have RF activity.

Antibodies, Monoclonal↗
PubMed1990

Attenuation of tumor necrosis factor-induced endothelial cell cytotoxicity and neutrophil chemiluminescence.

Our laboratory has previously shown that the administration of tumor necrosis factor (TNF), a cytokine produced by activated mononuclear cells, to guinea pigs produces a syndrome similar to gram-negative sepsis or ARDS. Pentoxifylline (PTX), a methylxanthine, protects against TNF-induced and sepsis-induced acute lung injury in vivo. We now report on in vitro cellular studies of PMN-mediated cellular injury and its attenuation. We studied TNF-induced bovine pulmonary artery endothelial cell (EC) cytotoxicity both with and without PMN. A 51Cr release assay was used to measure EC damage. Further, we investigated PMN function in response to TNF by measuring chemiluminescence. Agents that attenuate EC damage and PMN activation were evaluated in the above assays. Results revealed that TNF causes EC injury (p less than 0.05) and PMN increase TNF-induced EC injury. Furthermore, PTX, aminophylline (AMPH), caffeine, and forskolin attenuate TNF-induced EC cytotoxicity only in the presence of PMN (p less than 0.05). Of interest, dibutyryl cAMP (DBcAMP) protects EC from TNF-induced injury both with and without PMN. Agents that may increase cAMP levels in PMN (PTX, DBcAMP, forskolin, isobutyl methylxanthine, and terbutaline) significantly attenuate TNF-induced PMN chemiluminescence (p less than 0.05). We conclude that TNF causes EC damage and PMN increase this damage. Furthermore, PTX, AMPH, caffeine, and forskolin can attenuate TNF-induced EC injury in the presence of PMN, whereas DBcAMP attenuates TNF-induced EC injury with and without PMN. In addition, agents that may increase intracellular cAMP levels in PMN can attenuate TNF-induced PMN chemiluminescence. Thus, these agents likely attenuate TNF-induced PMN-mediated EC injury through their inhibitory effects on PMN.

Aminophylline↗
PubMed1990

Treatment of limited small-cell lung cancer with etoposide and cisplatin alternating with vincristine, doxorubicin, and cyclophosphamide versus concurrent etoposide, vincristine, doxorubicin, and cyclophosphamide and chest radiotherapy: a Southwest Oncology Group Study.

The Goldie-Coldman model explaining the kinetics of tumor cell kill and drug resistance has a potential application in designing chemotherapy regimes. In this Southwest Oncology Group (SWOG) trial we tested the alternation of two potentially noncrossresistant drug combinations with a concurrent drug combination in patients with limited small-cell lung cancer. The concurrent drug combination consisted of etoposide (VP-16), 75 mg/m2/intravenously (IV), days 1, 2, and 3; vincristine, 1.0 mg/m2/IV, days 1 and 8; Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), 40 mg/m2/IV, day 1; and cyclophosphamide, 750 mg/m2/IV, day 1 (EVAC). The alternating combination consisted of VP-16, 100 mg/m2/IV, days 1, 2, and 3; and cisplatin (CDDP), 100 mg/m2/IV, day 1, alternating with vincristine, 1.0 mg/m2/IV, days 1 and 8; Adriamycin, 50 mg/m2/IV, day 1; and cyclophosphamide, 750 mg/m2/IV, day 1 (VP-16/CDDP-VAC). Chemotherapy was administered at 3-week intervals for six cycles both before and after chest (5,000 rads/5 weeks) and whole brain radiotherapy (3,000 rads/2 weeks). One hundred ninety-nine patients received EVAC and 201 received the alternating combination. There was no significant difference in the response rate to the initial six cycles of treatment with EVAC (CR, 40%) versus the alternating combination (CR, 38%). There was no significant difference between the best response, EVAC (CR, 48%) and VP-16/CDDP-VAC (CR, 51%). Median survival for all randomized patients on EVAC is 15.1 months versus 16.5 months on the alternating combination (P = .58). Toxicities consisted primarily of bone marrow suppression, anorexia, nausea and vomiting, peripheral neuropathies, and alopecia. As in previous trials, the chest was the most common site of relapse (33%). There were no differences in the incidence and sites of relapse between the two treatment arms. These treatments appear equally effective at inducing remission and prolonging survival in patients with small-cell lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Concurrent chemotherapy/radiotherapy for limited small-cell lung carcinoma: a Southwest Oncology Group Study.

The Southwest Oncology Group (SWOG) has conducted a phase II study to explore the efficacy and toxicity of initial, concurrent use of radiation therapy with cisplatin, etoposide (VP-16), and vincristine in limited-stage small-cell carcinoma of the lung. Two courses of cisplatin, VP-16, and vincristine chemotherapy were given with concurrent radiotherapy (XRT) to the primary tumor to a total dose of 4,500 cGy. Elective brain XRT was given to all patients concurrent with a third course of cisplatin/VP-16 therapy. Consolidation chemotherapy consisting of vincristine, methotrexate, and VP-16 alternating with Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH) and cyclophosphamide, was given for 12 weeks following the initial induction chemotherapy/XRT program. Patients with a complete response had all therapy discontinued. Among 154 eligible patients treated, the complete response rate was 56%, with a partial response rate of 27%. The median survival is 17.5 months with an estimated 30% survival rate at 4 years from initiation of treatment. Combined modality toxicities were acceptable with the predominant toxicity being moderate to severe leukopenia and mild radiation esophagitis. The results of this treatment program appear superior to any previously reported by our group and compare favorably to those in the literature at large.

Adult↗
PubMed1990

Determinants of improved outcome in small-cell lung cancer: an analysis of the 2,580-patient Southwest Oncology Group data base.

We analyzed the 2,580-patient Southwest Oncology Group (SWOG) small-cell lung cancer data base from 1976 to 1988 in order to (1) determine the prognostic value of favorable demographic and tumor-related factors and therapy programs using Cox multivariate analyses in limited- and extensive-stage disease (LD, ED), and (2) define patient subgroups with significantly different survivals using recursive partitioning and amalgamation (RPA) analysis to refine the current two-stage system. Cox multivariate models were applied to 1,363 patients in six LD trials: good performance status, female sex, age less than 70 years, white race, and normal lactate dehydrogenase (LDH) were significant favorable independent predictors. Concurrent chemoradiotherapy was also a strong independent predictor of survival. For 1,217 patients in four ED trials, a normal LDH, treatment with an intensive multidrug regimen, and a single metastatic lesion were favorable independent variables in the Cox model. RPA analysis of 1,137 patients in recent LD and ED trials resulted in a regression tree in which the most important prognostic split was LD versus ED. Normal or abnormal LDH, absence or presence of a pleural effusion, and age less than 70 or greater than or equal to 70 years were important in LD, but only LDH was significant in ED. The terminal nodes of the regression tree were amalgamated to form four distinct prognostic subgroups with median survivals of 19.0, 12.5, 10.5, and 6.3 months (P less than .0001). The best survival occurred for younger patients with "true" LD: no effusion and normal LDH. The two intermediate patient subgroups had either LD or ED but still lived significantly longer than those patients with true ED (elevated LDH). This analysis suggests that although several factors were independent prognostic variables in LD in the Cox models, a smaller number of variables can be used to form important prognostic subgroups through RPA. The LDH emerged as a highly significant factor, but performance status and sex did not. A refinement of the current staging system should be made if our results can be confirmed with a combined-group data base analysis.

Adult↗
PubMed1990

Solitary brain metastasis: results of an RTOG/SWOG protocol evaluation surgery + RT versus RT alone.

From 1983 through 1986, the Southwest Oncology Group and Radiation Therapy Oncology Group conducted an intergroup study designed to evaluate the effectiveness of surgical resection in those patients with solitary central nervous system (CNS) metastases. The study was initially designed as a prospective randomized trial. Because of difficulty accruing patients, the registration format was altered and the patients were placed on study according to physician preference. Ninety-seven patients were registered on study and 80 patients were eventually analyzed. Fifty-five patients underwent radiation therapy alone and 25 patients received surgery and radiation. Fifty-nine percent of those patients undergoing radiation therapy alone improved or stabilized while 79% of those patients undergoing surgery and radiation therapy improved or stabilized. Eventually, 22% of the surgically treated patients failed in the brain while 45% of the patients undergoing radiation therapy exhibited a CNS relapse. Survival was improved when corrected for other prognostic factors in those patients undergoing surgical resection. Although not a prospective randomized trial, this study does suggest an improvement in the survival of a select group of patients able to tolerate neurosurgical resection.

Brain Neoplasms↗
PubMed1989

Characterization of four homologous L chain variable region genes that are related to 6B6.6 idiotype positive human rheumatoid factor L chains.

A significant proportion of monoclonal IgM rheumatoid factors (RF) from patients with mixed cryoglobulinemia express a KIIIa L chain-associated cross-reactive idiotype, termed 6B6.6. Previously, we reported the isolation from a patient with a monoclonal RF of a Vk gene, termed Humkv328, whose deduced amino acid sequence differs by three and seven residues from the L chains of the 6B6.6-positive RF Les and Pom, respectively. To further delineate the genetic basis of the 6B6.6 cross-reactive idiotype, we isolated from the same patient another Vk gene, termed Humkv329, which differs from kv328 by only three bases over a stretch of 1331 nucleotides sequenced. However, kv329 has a stop codon at amino acid position 94, and is thus a pseudogene. Therefore, we screened a second genomic library from an unrelated individual and isolated two potential function Vk genes (i.e., Humkv328h2 and Humkv328h5) which are highly homologous to Humkv328. All three potential functional Vk genes differ from each other by one to six bases over a 1331-bp stretch and all encode the same Vk region amino acid sequence. Among the six bases by which Humkv328h5 differs from Humkv328, two are in the conserved pentadecanucleotide region, which is known to be important in the regulation of k L chain transcription. In the future it will be important to ascertain the potential association of polymorphisms in the conserved pentadecanucleotide region with RF associated autoimmune and lymphoproliferative diseases.

Amino Acid Sequence↗
PubMed1989

Effects of tumor necrosis factor on PMN chemotaxis, chemiluminescence, and elastase activity.

Tumor necrosis factor (TNF) has been proposed as an important mediator of the inflammatory response in acute lung injury. To better understand polymorphonuclear leukocyte (PMN) activation during acute lung injury, we evaluated the effects of TNF on several in vitro PMN functions, including chemotaxis, chemiluminescence, and elastase activity. In the chemotaxis assay using a modified Boyden chamber, TNF alone or with N-formyl-methionyl-leucyl-phenylalanine (FMLP, 10(-8) mol/L) did not alter PMN migration. TNF suspended with 1% zymosan-activated serum (ZAS) increased PMN migration at low concentrations and decreased migration at high concentrations (control 99 +/- 4.8 microns, n = 9; TNF 0.1 ng/ml 135 +/- 9.4 microns, n = 5, p less than 0.01; TNF 1000 ng/ml 62 +/- 7.5 microns, n = 5, p less than 0.01). In the chemiluminescence assay, TNF (1000 ng/ml) induced a 3-fold increase in the PMN chemiluminescent response. However, TNF incubated with PMN did not cause an increase in supernatant elastase activity. These data reveal TNF induced the production of PMN reactive oxygen species as evidenced by an increased chemiluminescent response. Whereas TNF increased chemotaxis at low concentrations in the presence of 1% ZAS, high concentrations of TNF similar to levels detected in septic shock caused a decrease in chemotaxis that might contribute to retaining PMN in sites of inflammation. It is thus suggested that TNF may contribute to inflammation by stimulating the production of PMN-reactive oxygen species and modulating-PMN chemotaxis.

Acridines↗
PubMed1988

Incidence of three cross-reactive idiotypes on human rheumatoid factor paraproteins.

The basis for rheumatoid factor (RF) production in autoimmune or lymphoproliferative diseases cannot be understood without defining the molecular factors that dictate RF structure and specificity. Recently three different mAb (6B6.6, 17.109, and G6) have been developed that define cross-reactive idiotypes (CRI) on intact L or H chains of human monoclonal RF cryoglobulins. However, the true incidence of these CRI among RF and their relationship to each other have not been delineated. In the present experiments, a panel of 163 randomly selected IgM paraproteins was evaluated for the expression of the two kappa L chain CRI, 6B6.6 and 17.109, and the H chain CRI, G6. Among the paraproteins with kappa L chains, 14% expressed the 17.109 CRI, and 9% expressed the 6B6.6 CRI. Both ELISA and Western immunoblotting experiments showed that the two L chain CRI were mutually exclusive. Anti-IgG activity was documented in 22 of the IgM-kappa paraproteins, among which mAb 6B6.6 reacted with 7 (32%) and mAb 17.109 with 6 (27%). Both CRI were expressed exclusively by L chains within the kappaIII variable gene subgroup. Although 17.109 CRI+ paraproteins had kappaIIIb L chains, none of the 6B6.6 CRI+ paraproteins possessed L chains with this kappa sub-subgroup specific Ag. The G6 CRI was found predominantly among RF paraproteins and was frequently yet not exclusively associated with the 17.109 CRI+ L chains. Additional experiments were performed on a panel of normal adult human sera and documented the presence of 6B6.6 and 17.109 CRI on a small percentage (0.1 to 2.0%) of IgM from most individuals. These data indicate that 1) the mAb 6B6.6 and 17.109 identify two major and distinct CRI among IgM-RF paraproteins, 2) both CRI are associated exclusively with kappaIII L chains, 3) kappaIIIb and kappaIII non-b L chains are equally prevalent among IgM-RF, 4) the G6 H chain CRI is frequently associated with 17.109 CRI+ L chains, but not with 6B6.6 CRI+ L chains, and 5) although the ability to make 6B6.6 and 17.109 CRI+ kappa L chains is common in humans, these CRI are present in low concentrations in normal IgM.

Adolescent↗
PubMed1988

Polymorphonuclear leukocyte inhibition by therapeutic concentrations of theophylline is mediated by cyclic-3',5'-adenosine monophosphate.

Although theophylline has been used for many years as a principal agent in treatment of reversible obstructive airway disease, the mechanism of drug activity at therapeutic concentrations remains unclear. Because inflammatory mediators generated by polymorphonuclear leukocytes (PMN) may be important in the pathogenesis of airway hyperreactivity, the effects of theophylline upon PMN activation were studied. Theophylline (9 micrograms/ml, 50 microM) inhibited PMN leukotriene B4 generation by 50%, oxygen metabolite generation by 60%, and decreased the concentration of isoproterenol required to cause 50% maximal inhibition (EC50) from 13 to 3.3 nM. The same theophylline concentration increased PMN cAMP by 196% at 45 s after cell activation. A higher theophylline concentrations (18 micrograms/ml, 100 microM) decreased leukotriene B4 generation by more than 90%. Eight healthy volunteers were studied before and after 1 wk of oral theophylline administration (mean plasma theophylline level achieved was 9.4 micrograms/ml). Basal and 1-min postactivation cAMP concentrations were increased 160 and 157%, respectively, in PMN specimens after theophylline administration. The EC50 for isoproterenol was reduced by 50%, and the cAMP elevation induced by isoproterenol was increased by 200%. Because theophylline inhibition of PMN function appeared to be associated with both an increase in cAMP and a decrease in intracellular calcium, these effects may be relevant to both the therapeutic and adverse pharmacologic actions of theophylline. Because inflammatory mediator release was reduced by low drug concentrations, inhibition of PMN function may be an effect of therapeutic theophylline administration.

Adult↗
PubMed1988

Idiotypic characteristics of rheumatoid factors.

We have used monoclonal anti-idiotypic antibodies and "sequence-dependent" heterologous anti-peptide antibodies of predefined specificities against either the complementarity determining or framework regions of the human immunoglobulin molecules to delineate the structural and genetic basis of human IgM rheumatoid factor (RF) paraprotein formation. Human IgM RF paraproteins were found to be most commonly reactive with anti-kappa III subgroup anti-sera (88%). These RFs could be subdivided into two major light chain cross reactive idiotype (CRI) groups with the monoclonal antibodies 17.109 and 6B6.6. The two CRI positive light chains are likely encoded by two distinct V kappa germline genes, designated respectively Humkv325 (VkRF) and Humkv328. These CRIs are also associated with specificities other than RFs. Heavy chain analysis of RFs revealed that the product of the Humkv325 gene frequently assemble with heavy chains of the VHI subgroup, but will assemble with the heavy chains of other subgroups less frequently. The VHI heavy chains RFs were found to carry frequently the G6 CRI marker.

Antibodies, Monoclonal↗
PubMed1988

Aging and drug interactions. II. Effect of phenytoin and smoking on the oxidation of theophylline and cortisol in healthy men.

The effect of age on the induction of theophylline metabolism by phenytoin was examined in healthy young and old male cigarette smokers (greater than or equal to 20 cigarettes/day) and nonsmokers. Two single dose studies of theophylline pharmacokinetics were performed, one as a base-line control and another after a 2-week course of phenytoin. Phenytoin was administered as an i.v. loading dose followed by oral ingestion. The dose was adjusted to achieve total phenytoin plasma concentrations within a low therapeutic range (10-13 micrograms/ml). Free phenytoin concentrations in plasma were slightly higher in old (nonsmokers 0.84 +/- 0.13 micrograms/ml; smokers 0.89 +/- 0.12 micrograms/ml) than in young (nonsmokers 0.75 +/- 0.10 micrograms/ml; smokers 0.72 +/- 0.10 micrograms/ml) subjects, but the differences were not significant. Base-line plasma theophylline clearance was 30% lower in old compared with young nonsmokers (34.0 +/- 2.5 vs. 48.8 +/- 2.6 ml/hr/kg, P less than .001), whereas the small age difference between old and young smokers (86.0 +/- 8.4 vs. 72.4 +/- 8.0 ml/hr/kg) was not significant. Smokers had higher values of theophylline clearance than nonsmokers regardless of age. Half-life was prolonged in old nonsmokers in proportion to decreased clearance, despite a slight decrease in volume of distribution. Phenytoin induced theophylline metabolism to an equal degree in both age groups and in both smokers (young 42.6 +/- 6.5%; old 47.3 +/- 3.6%) and nonsmokers (young 56.3 +/- 8.8%; old 45.4 +/- 6.4%). The magnitude of its induction in smokers was additive to that of cigarette smoking. Old age was associated with a modest selective reduction in N-demethylated metabolic pathways to 3-methylxanthine and 1-methyluric acid, whereas smoking preferentially induced the formation of these products. Phenytoin increased the production of all theophylline primary metabolites to an equal degree in both old and young subjects. The urinary excretion of 6 beta-hydroxycortisol was not influenced significantly by age or smoking and increased 2- to 3-fold in all subject groups with phenytoin. These results confirm earlier observations of a reduction in basal oxidative capacity in elderly nonsmoking males. They also demonstrate that the ability to induce the metabolism of theophylline by smoking or phenytoin and the ability to induce the metabolism of cortisol by phenytoin are maintained in old age.

Adult↗