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S N Goodman

Publications and source records attributed to S N Goodman.

67 records · Page 4Linked to original sources
PubMed1993

Overexpression of the p53 tumor suppressor gene product in primary lung adenocarcinomas is associated with cigarette smoking.

Mutations in the p53 tumor suppressor gene are frequently observed in primary lung adenocarcinomas, suggesting that these mutations are critical events in the malignant transformation of airway cells. These mutations are often associated with stabilization of the p53 gene product, resulting in the accumulation of p53 protein. In this study, 70 formalin-fixed, paraffin-embedded primary lung adenocarcinomas resected for potential cure were examined for p53 overexpression. These 70 lung adenocarcinomas were obtained from a series of patients with well-documented clinical histories, and all 70 carcinomas had been previously evaluated for point mutations in codon 12 of the K-ras oncogene. Overexpression of the p53 protein was detected using an antigen retrieval system (Target Unmasking Fluid) and the anti-p53 antibody CM-1. CM-1 is a polyclonal antibody directed against the wild-type p53 protein. Overexpression of the p53 protein was found in 23 (33%) of the 70 lung adenocarcinomas. In all 23 cases, overexpression was confined to neoplastic cells. Overexpression of the p53 protein correlated with cigarette smoking: 10 (56%) of the 18 adenocarcinomas from patients who were current smokers overexpressed p53 compared with 13 (33%) of the 40 adenocarcinomas from patients who had quit smoking and 0 (0%) of the 12 adenocarcinomas from patients who had never smoked (p = 0.002, trend test). Overexpression of the p53 protein was also related to the degree of histologic differentiation: 48% of the p53 negative carcinomas were well differentiated, whereas only 13% (p = 0.003) of the carcinomas in which p53 was overexpressed were well differentiated. Overexpression of the p53 protein did not correlate with point mutations in codon 12 of the K-ras oncogene, nor did it correlate with tumor stage or patient survival. These findings indicate that p53 protein is frequently overexpressed in primary lung adenocarcinomas. Furthermore, the association of tobacco smoking with this overexpression suggests that the p53 gene is a target of specific mutagens in tobacco smoke.

Adenocarcinoma↗
PubMed1993

Efficacy of immune globulin in preventing complications of bone marrow transplantation: a meta-analysis.

To assess the efficacy of immune globulin in preventing CMV infection, interstitial pneumonia, GVHD and death after BMT, we reviewed and synthesized data from 12 published studies (with 1282 patients) in which immune globulin was used prophylactically in BMT patients, controls were included and clinical outcomes were assessed. Data synthesis indicates that immune globulin significantly reduces fatal CMV infection (odds ratio (OR) 0.47, 95% confidence interval (CI) 0.23-0.99), CMV pneumonia (OR 0.61, CI 0.42-0.89), non-CMV interstitial pneumonia (OR 0.57, CI 0.35-0.95) and total mortality (OR 0.74, CI 0.55-0.99). The reduction in acute GVHD was not quite significant (OR CI 0.45-1.02). Complications decrease with both hyperimmune and conventional immune globulin. For CMV-negative transplant recipients, immune globulin decreases symptomatic CMV infection (OR 0.55, CI 0.31-0.94) and interstitial pneumonia (OR 0.34, CI 0.15-0.77). For CMV-positive recipients, immune globulin prevents interstitial pneumonia (OR 0.45, CI 0.26-0.80) but not symptomatic CMV infection (CI 0.41-2.80). We conclude that immune globulin is efficacious in preventing major complications of BMT in both CMV-negative and CMV-positive recipients.

Adult↗
PubMed1993

K-ras oncogene activation in adenocarcinoma of the human pancreas. A study of 82 carcinomas using a combination of mutant-enriched polymerase chain reaction analysis and allele-specific oligonucleotide hybridization.

We examined 82 surgically resected or biopsied, formalin-fixed, paraffin-embedded primary adenocarcinomas of the pancreas for the presence of activating point mutations in codon 12 of the K-ras oncogene. Mutations were detected using primer-mediated, mutant-enriched, polymerase chain reaction-restriction fragment length polymorphism analysis and characterized further by allele-specific oligonucleotide hybridization. This combination of mutant-enriched polymerase chain reaction-restriction fragment length polymorphism analysis and allele-specific oligonucleotide hybridization results in a rapid and sensitive characterization of the mutations in codon 12 of K-ras. Sixty-eight (83%) of the 82 carcinomas examined harbored a point mutation. Of the 68 mutations, 33 (49%) were guanine to adenine transitions, 27 (39%) were guanine to thymine transversions, and eight (12%) were guanine to cytosine transversions. Mutations were found in carcinomas of the head (61 of 75, 81%) as well as in carcinomas of the body or tail (seven of seven, 100%) of the pancreas. The overall prevalence of K-ras point mutations in adenocarcinomas of the pancreas obtained from patients who smoked cigarettes at some point during their lives (88%; 86% in current smokers and 89% in ex-smokers) was greater than that seen in pancreatic adenocarcinomas from patients who never smoked cigarettes (68%, P = 0.046). The presence of K-ras point mutations did not correlate with tumor ploidy, tumor proliferating index, or patient survival. These results demonstrate that primer-mediated, mutant-enriched polymerase chain reaction-restriction fragment length polymorphism analysis combined with allele-specific oligonucleotide hybridization can be used to detect and characterize mutations in codon 12 of the K-ras oncogene in formalin-fixed, paraffin-embedded tissues, and the results confirm that activating point mutations in codon 12 of the K-ras oncogene occur frequently in adenocarcinomas of the pancreas.

Adenocarcinoma↗
PubMed1992

A comment on replication, p-values and evidence.

It is conventionally thought that a small p-value confers high credibility on the observed alternative hypothesis, and that a repetition of the same experiment will have a high probability of resulting again in statistical significance. It is shown that if the observed difference is the true one, the probability of repeating a statistically significant result, the 'replication probability', is substantially lower than expected. The reason for this is a mistake that generates other seeming paradoxes: the interpretation of the post-trial p-value in the same way as the pre-trial alpha error. The replication probability can be used as a frequentist counterpart of Bayesian and likelihood methods to show that p-values overstate the evidence against the null hypothesis.

Bias↗
PubMed1991

Multivariate analysis of the risk of stomach cancer after ulcer surgery in an Amsterdam cohort of postgastrectomy patients.

Although gastric cancer incidence is decreasing in the western world, it remains an important cause of death, and there has been debate about screening persons who have undergone gastrectomy for benign ulcers. The authors analyzed risk factors for stomach cancer mortality in an Amsterdam cohort of 2,633 postgastrectomy patients, followed from their initial surgery between 1931 and 1960 until 1975, with 99.7% complete follow-up. Increased stomach cancer mortality was observed in the study population (compared with the general Dutch population) among males 25 years or more after surgery (observed/expected, 5.0; 95% confidence interval (Cl) 2.8-8.3), and among females 15-24 years postoperatively (observed/expected, 3.5; 95% Cl 1.0-9.0). A multivariate Poisson regression analysis showed that after control for age at time of surgery and calendar year of operation, the most important risk factors were time since surgery (0-4 years, relative risk (RR) = 1.0; 5-14 years, RR = 4.1, 95% Cl 0.93-18.5; 15-24 years, RR = 9.4, 95% Cl 2.1-42.3; and 25-46 years, RR = 55.6, 95% Cl 11.7-265.4) and ulcer location (gastric versus duodenal ulcer, RR = 2.6, 95% Cl 1.4-4.8). Surveillance for postgastrectomy cancer could be considered 15-25 years after a patient undergoes surgery for gastric ulcer disease.

Adult↗
PubMed1991

Influence of dilated cardiomyopathy, myocarditis and cardiac transplantation on the relation between plasma atrial natriuretic factor and atrial pressures.

To determine whether dilated cardiomyopathy, myocarditis or cardiac transplantation affect the relation between plasma immunoreactive atrial natriuretic factor (ANF) and cardiac filling pressures, right atrial plasma ANF concentration, pulmonary arterial wedge pressure and right atrial pressure were measured in patients with dilated cardiomyopathy (n = 48), dilated cardiomyopathy secondary to myocarditis (n = 20) and prior cardiac transplantation (n = 34). ANF level significantly correlated with both pulmonary arterial wedge and right atrial pressures in patients with dilated cardiomyopathy; however, the presence or absence of myocarditis did not significantly alter these relations (p = 0.88 and p = 0.33 for interaction terms, respectively). For the combined group the ANF-pulmonary arterial wedge pressure relation had a slope of 8.1 pg/ml/mm Hg (95% confidence interval (CI), 5.4 to 10.8; p = 0.0001) and the ANF-right atrial pressure relation a slope of 13.6 pg/ml/mm Hg (CI, 8.5 to 18.7; p = 0.0001). Receiver operator curve analysis identified an optimal dividing point of ANF 150 pg/ml with 100% (CI, 72 to 100%) of patients with right atrial pressure greater than or equal to 8 mm Hg having ANF greater than or equal to 150 pg/ml, but only 56% (CI, 42 to 69%) with pressure less than 8 mm Hg having ANF less than 150 pg/ml. Unlike the patients with cardiomyopathy (with or without myocarditis), cardiac transplant recipients displayed no correlation between ANF level and either pulmonary arterial wedge pressure (p = 0.50) or right atrial pressure (p = 0.29) despite similarly elevated ANF concentrations (mean +/- standard deviation 168 (83) pg/ml in transplant patients versus 185 (114) pg/ml in cardiomyopathy patients). It is concluded that left and right intracardiac pressures are important determinants of circulating ANF level unaffected by inflammation in patients with cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Neuroblastoma screening data. An epidemiologic analysis.

Neuroblastoma is one of the most common malignant neoplasms in children under age 5 years. Little progress has been made in the prognosis of advanced stage disease in the past three decades. Since the development in the 1960s of a simple urine test to detect neuroblastoma metabolites, there has been hope that mortality from this disease could be reduced by early detection via mass screening of young infants. Encouraging reports from Japan on mass screening programs instituted in the 1970s have been appearing in the medical literature since 1982, resulting in widespread interest in screening. This article applies standard epidemiologic criteria for screening evaluations to the Japanese reports. We find that the data needed to definitively assess the value of screening were not a part of those reports and that the benefits claimed from the reported data could be due to overdiagnosis. In addition, the most recent Japanese data, combined with recent advances in biologic understanding of neuroblastoma, show that screening at age 6 months may not detect tumors with poor prognoses. Even if it could, it is uncertain whether those outcomes could be substantially altered by earlier diagnosis. Although a final verdict on the value of neuroblastoma screening is not yet possible, these neuroblastoma studies are an excellent example of how screening results must be viewed with extreme caution in the absence of age-specific, population-based incidence and mortality rates.

Age Factors↗
PubMed1990

Detection of minimal residual T cell acute lymphoblastic leukemia by flow cytometry.

We have developed a flow cytometric assay for the determination of cellular expression of terminal deoxynucleotidyl transferase (TdT) and applied this to the detection of minimal residual T cell acute lymphoblastic leukemia (T-ALL). The flow cytometric assay for TdT demonstrated requisite specificity: TdT was localized to the nucleus, and was detected in MOLT3 T lymphoblasts, clinical T-ALL samples, and normal bone marrow B lymphoid precursors, but in neither the KG1a myeloid leukemia cell line nor normal myeloid cells. Co-expression of TdT and the pan T cell marker CD5 was used to quantify T lymphoblasts. 0.25 +/- 0.13% of normal adult bone marrow CD5+ cells were TdT+; these may represent early T lymphoid precursors. When admixed with normal bone marrow, CD5+TdT+ leukemic cells could be detected above background levels at an added concentration of 0.035% (95% confidence interval 0.028-0.43%). Long term follow-up of a large number of patients will be required to determine the clinical significance of a minimal burden of leukemic cells.

Antibodies, Monoclonal↗
PubMed1989

Meta-analysis and evidence.

Meta-analysis is the science of combining evidence from different studies, but traditional statistical techniques contain neither a formal definition nor a measure of evidence. It is argued in this paper that the log-likelihood ratio, as a measure of the "weight of evidence," can be a very useful tool in the meta-analysis. The mathematics and the philosophy behind the use of this index are introduced. The construction and interpretation of "support curves" in fixed and random-effects models are presented. The application of evidential techniques is illustrated on six trials of aspirin therapy previously presented by Canner. The possible dangers of focusing on statistical error rates instead of evidence are discussed.

Aspirin↗
PubMed1988

Evidence and scientific research.

This commentary reviews the arguments for and against the use of p-values put forward in the Journal and other forums, and shows that they are all missing both a measure and concept of "evidence." The mathematics and logic of evidential theory are presented, with the log-likelihood ratio used as the measure of evidence. The profoundly different philosophy behind evidential methods (as compared to traditional ones) is presented, as well as a comparative example showing the difference between the two approaches. The reasons why we mistakenly ascribe evidential meaning to p-values and related measures are discussed. Unfamiliarity with the technology and philosophy of evidence is seen as the main reason why certain arguments about p-values persist, and why they are frequently contradictory and confusing.

Bayes Theorem↗
PubMedDate not supplied

Bayesian communication: a clinically significant paradigm for electronic publication.

OBJECTIVE: To develop a model for Bayesian communication to enable readers to make reported data more relevant by including their prior knowledge and values. BACKGROUND: To change their practice, clinicians need good evidence, yet they also need to make new technology applicable to their local knowledge and circumstances. Availability of the Web has the potential for greatly affecting the scientific communication process between research and clinician. Going beyond format changes and hyperlinking, Bayesian communication enables readers to make reported data more relevant by including their prior knowledge and values. This paper addresses the needs and implications for Bayesian communication. FORMULATION: Literature review and development of specifications from readers', authors', publishers', and computers' perspectives consistent with formal requirements for Bayesian reasoning. RESULTS: Seventeen specifications were developed, which included eight for readers (express prior knowledge, view effect size and variability, express threshold, make inferences, view explanation, evaluate study and statistical quality, synthesize multiple studies, and view prior beliefs of the community), three for authors (protect the author's investment, publish enough information, make authoring easy), three for publishers (limit liability, scale up, and establish a business model), and two for computers (incorporate into reading process, use familiar interface metaphors). A sample client-only prototype is available at http://omie.med.jhmi.edu/bayes. CONCLUSION: Bayesian communication has formal justification consistent with the needs of readers and can best be implemented in an online environment. Much research must be done to establish whether the formalism and the reality of readers' needs can meet.

Bayes Theorem↗
PubMedDate not supplied

Multivariate analysis of prognostic features in malignant pleural effusions from breast cancer patients.

To identify prognostic indicators in breast cancer patients with malignant pleural effusions, we analyzed the cytopathologic features of 57 fluids representing the first pathologic diagnosis of a distant metastasis in these women. The specimens were analyzed prior to reviewing the clinical records. The median survival of 55 patients who died of the disease was five months following the effusion diagnosis (range, 1-114). Univariate analysis identified three cytopathologic features that correlated with relatively prolonged survival: arrangement of tumor cells in spheroids, slight nuclear atypia and low mitotic rate. Women whose tumor cells formed spheroids survived a median of 24.5 months as compared to 4 months for women with all other architectural patterns (P = .004). Multivariate analysis revealed that slight nuclear atypia and low mitotic rate strongly correlated with spheroid formation. Since breast cancers that form spheroids in effusions portend a relatively favorable prognosis, we recommend that cytopathologists comment on this pattern when reporting on metastatic breast carcinoma in pleural fluids.

Adult↗