Objective: To compare indicators of heterocyclic amine (HCA) exposure with HCA concentrations in home-cooked meat samples. Methods: Pan-fried hamburger and steak samples were obtained from ...individuals stating a preference for medium, well done and very well done meat. Concentrations of DiMeIQx, IFP, MeIQx and PhIP were determined by HPLC. Results: HCA concentrations at the three doneness levels were not significantly different using the participants' self-reported doneness preference to categorize samples. Using doneness levels determined at the time the meat was cooked and photograph analysis to categorize samples, HCA concentrations increased with doneness level and significant differences were observed between the very well done and lower doneness levels. When assigned to doneness levels by photograph analysis, mean concentrations (ng/g cooked meat) of DiMeIQx, IFP, MeIQx, and PhIP were 0.18, 0.16, 0.65 and 0.47 in well done hamburger and 0.61, 0.74, 1.88 and 2.04 in very well done hamburger. In steak, mean concentrations were 0.24, 0.10, 0.79 and 0.59 in well done steak and 0.45, 0.14, 1.87 and 0.62 in very well done steak. Conclusions: HCA levels in home-cooked meat samples were significantly different when samples were visually classified for doneness, but not when self-reported doneness preference was used to classify doneness.
We analyzed data from a population-based, multi-center, case-control study to determine whether the occurrence of histologic types of uterine sarcoma is related to exogenous hormone use and/or to two ...correlates of endogenous estrogens: excess weight and cigarette smoking.
One hundred sixty-seven women with newly-diagnosed uterine sarcoma (56 leiomyosarcoma, 85 mixed mullerian tumors, and 26 endometrial stromal sarcomas) were interviewed by telephone regarding possible risk factors for these neoplasms, For comparison, 208 women identified at random from the general population of the study areas were interviewed as controls.
Use of oral contraceptives was positively associated with the risk of leiomyosarcoma (odds ratios OR = 1.7, 95% confidence interval CI = 0.7, 4.1), primarily among women who last used these medications 15 or more years prior to diagnosis. Use of noncontraceptive estrogens was directly associated with the risk of mixed mullerian tumors, but only among recent and long-term users of these medications. Women in the highest quantile of body mass index (> or = 27.5 kg/m2) one year prior to diagnosis were at increased risk of each type of uterine sarcoma (leiomyosarcoma, OR = 2.5, 95% CI = 1.1, 5.7; mixed mullerian tumors, OR = 2.9, 95% CI = 1.3, 6.7; stromal sarcoma, OR = 3.5, 95% CI = 1.1, 10.9). Women who had ever smoked cigarettes were at reduced risk of leiomyosarcoma (OR = 0.6, 95% CI = 0.3, 1.1) and stromal sarcoma (OR = 0.5, 95% CI = 0.2, 1.2), but the relationship was not more pronounced among heavy smokers; no association with smoking was observed with mixed mullerian tumors.
Several of these findings parallel those from studies of endometrial carcinoma and may indicate a role for unopposed estrogen in the etiology of histologic types of uterine sarcoma.
Neural networks are capable of learning rich, nonlinear feature representations shown to be beneficial in many predictive tasks. In this work, we use such models to explore different geographical ...feature representations in the context of predicting colorectal cancer survival curves for patients in the state of Iowa, spanning the years 1989 to 2013. Specifically, we compare model performance using "area between the curves" (ABC) to assess (a) whether survival curves can be reasonably predicted for colorectal cancer patients in the state of Iowa, (b) whether geographical features improve predictive performance, (c) whether a simple binary representation, or a richer, spectral analysis-elicited representation perform better, and (d) whether spectral analysis-based representations can be improved upon by leveraging geographically-descriptive features. In exploring (d), we devise a similarity-based spectral analysis procedure, which allows for the combination of geographically relational and geographically descriptive features. Our findings suggest that survival curves can be reasonably estimated on average, with predictive performance deviating at the five-year survival mark among all models. We also find that geographical features improve predictive performance, and that better performance is obtained using richer, spectral analysis-elicited features. Furthermore, we find that similarity-based spectral analysis-elicited representations improve upon the original spectral analysis results by approximately 40%.
Objective. Breast cancer screening and treatment data are often limited to restricted populations, including women older than 65 years old. The goal of this project was to develop procedures to link ...tumor registry and insurance claims databases on women younger than 65 years old with breast cancer and to assess the accuracy and validity of the linked dataset. Methods. Iowa Cancer Registry (ICR) and Wellmark Blue Cross/Blue Shield of Iowa (BC/BS) membership files of women with incident in situ or invasive breast cancer from 1989 to 1996 were linked. An automated deterministic match was followed with visual inspection from three independent reviewers applying a matching protocol. Matched and overall registry data were compared to assess population representativeness. Claims from BC/BS for incident cases during 1994 were examined for coding of a recent breast cancer diagnosis or treatment. Results. The final dataset included 4,397 matched cases of patients aged 21 years and older from 1989 to 1996. The sociodemographic and tumor characteristics of the ICR population younger than 65 years old (n = 7,469) with breast cancer or carcinoma in situ were nearly identical with those of the matched patients younger than 65 years old (n = 3,449). Nearly all (96%) of the 445 matched incident cases in 1994 had claims data (CPT, DRG, or ICD-9 code) indicative of breast cancer. Treatment patterns varied by data source, with agreement ranging from 76% to 82%. Conclusions. The validity and generalizability of these data demonstrate their potential for further health services research among younger insured women with breast cancer. Additionally, the process outlined may be useful for developing other datasets to study other cancers in the population younger than 65 years old.
Recent reports have called into question the safety and effectiveness of electroconvulsive therapy (ECT).
To investigate these claims, the effects of ECT on clinical outcomes were examined as part of ...a retrospective, naturalistic study of 192 geriatric patients consecutively admitted between 1980 and 1987 to a large midwestern tertiary care center for the treatment of depression. Data were analyzed by a variety of parametric and nonparametric methods including ANOVA and survival analysis.
Patients who received ECT (N = 108) were more likely to exhibit psychomotor retardation and to have had prior courses of ECT than those who did not receive ECT (N = 84). Furthermore, despite the absence of differences in the overall rate or severity of medical comorbidity, patients receiving ECT were more likely to be alive at follow-up and to demonstrate greater clinical improvement than those treated only with pharmacotherapy.
These results confirm previous studies demonstrating the superior efficacy of ECT as compared with conventional pharmacotherapy treatment in patients hospitalized with depression and document its safety in long-term follow-up.
The primary objective of the study was to determine the safety and efficacy of transurethral microwave thermotherapy for the treatment of symptomatic benign prostatic hyperplasia. From March to ...August 1991, 150 patients were entered into a multi-site study and treated with transurethral microwave thermotherapy under a Food and Drug Administration approved protocol. Only patients with symmetrical trilobar or bilobar prostatic hypertrophy, peak flow rate of less than 15 cc per second (on 2 voided volumes of 150 cc or greater) and a total Madsen symptom score of more than 8 were treated. Transurethral microwave thermotherapy was performed with a 20F catheter and 1,296 MHz. microwave antenna for 60 minutes. The mean power achieved for this single session was 32.1 watts, with a mean power at maximum urethral temperature of 41.1 watts. Mean urethral temperature was 44.3C and the mean rectal temperature was 42.2C. The rectal and urethral temperatures were continuously monitored. Mean peak urinary flow rates, Madsen symptom score, post-void residual volume and improvement in motivating symptom to seek treatment were measured at 6 weeks, and 3, 6 and 12 months. Mean peak urinary flow rates improved 33% at 12 months (p < 0.0001). Overall, the mean Madsen symptom score improved 61% (p < 0.0001). The obstructive score and the irritative score improved 67% and 43%, respectively. Of 17 patients 12 (71%) reported improvement in weak stream when that was the motivating symptom to seek treatment. Of 28 men 18 (64%) reported improvement in nocturia, while 11 of 30 (37%) reported improvement in daytime frequency and 12 of 17 (71%) reported improvement in urgency. There was no statistically significant difference in post-void residual volume at 12 months from baseline. The treatment was well tolerated by all patients, and side effects were considered mild and transitory. Our study demonstrates the safety, effectiveness, patient tolerability and durability of transurethral microwave thermotherapy.
There have been few evaluations of the risk of acute nonlymphocytic leukemia (ANLL) following therapy for non-Hodgkin's lymphoma (NHL). Further, the relationship between cumulative dose of cytotoxic ...drug, radiation dose to active bone marrow, and the risk of ANLL following NHL have not been well described.
Our purpose was to examine the risk of ANLL in relationship to all prior treatment for NHL.
Within a cohort study of 11,386 2-year survivors of NHL, 35 case patients with secondary ANLL were identified and matched to 140 controls with NHL who did not develop ANLL. The primary eligibility criteria for the cohort included a diagnosis of NHL as a first primary cancer from January 1, 1965, through December 31, 1989; age 18 through 70 years at the time of initial diagnosis; and survival for 2 or more years without the development of a second invasive primary malignancy. Detailed information on chemotherapeutic drugs and radiotherapy was collected for all patients. Standard conditional logistic regression programs were used to estimate the relative risk (RR) of ANLL associated with specific therapies by comparing the exposure histories of case patients with individually matched controls.
Significant excesses of ANLL followed therapy with either prednimustine (RR = 13.4; 95% confidence interval CI = 1.1-156; P trend for dose < .05) or regimens containing mechlorethamine and procarbazine (RR = 12.6; 95% CI = 2.0-79; P < .05). Elevated risks of leukemia following therapy with chlorambucil were restricted to patients given cumulative doses of 1300 mg or more (RR = 6.5; 95% CI = 1.6-26; P < .05). Cyclophosphamide regimens were associated with a small, nonsignificant increased risk of ANLL (RR = 1.8;95% CI = 0.7-4.9), with most patients receiving relatively low cumulative doses (< 20,000 mg). Radiotherapy given at higher doses without alkylating agents was linked to a nonsignificant threefold risk of ANLL compared with lower dose radiation or no radiotherapy.
Our results suggest that prednimustine may be a human carcinogen, with a positive dose-response gradient evident for ANLL risk. The low, nonsignificant risk of leukemia associated with cyclophosphamide was reassuring because this drug is commonly used today. Despite the excesses of ANLL associated with specific therapies, secondary leukemia remains a rare occurrence following NHL. Of 10,000 NHL patients treated for 6 months with selected regimens including low cumulative doses of cyclophosphamide and followed for 10 years, an excess of four leukemias might be expected.
Background:
Health care changes during the past decade have resulted in a greater proportion of cutaneous melanoma (CM) cases diagnosed in nonhospital settings, increasing the potential for cases to ...be missed by population-based cancer registries.
Objective:
Our purpose was to assess changes in case-finding sources in Iowa from 1977 to 1994 and to determine the extent of underreporting for the State Health Registry of Iowa, a population-based cancer registry.
Methods:
This study examines changing trends in the incidence of CM and compares case-finding sources (hospitals/clinics, hospital pathology laboratories, and independent pathology laboratories). A survey of dermatologists serving Iowans provides estimates of underreporting.
Results:
During the period 1977 to 1994, invasive CM increased 82%, whereas in situ CM increased 900%. The proportion of CM cases diagnosed in independent pathology laboratories increased to 25% of all cases. A range of 10.4% to 17.1% underreporting was estimated based on the survey of dermatologists.
Conclusion:
To improve the accuracy of surveillance, population-based cancer registries need to make a greater effort accessing pathology reports from nonhospital settings. (J Am Acad Dermatol 1997;37:578-85.)
Clenbuterol is a beta2-adrenoceptor agonist primarily used for treating bronchospasm and alleviating the symptoms of chronic obstructive pulmonary disease (COPD) in the horse. In other species (rats, ...mice, sheep, and cattle), chronic high doses of clenbuterol (typically in the milligram per kilogram body weight range) has been shown to cause a muscle directed protein anabolic response. Clenbuterol can also modify muscle fibre composition and therefore potentially affect muscle function. This has implications for the performance of exercising horses being treated with therapeutic doses of clenbuterol (typically in the microgram per kilogram body weight range) for bronchospasm or COPD. It is not known whether clenbuterol treatment affects muscle fibre function in horses. The purpose of this study was to examine the effects of a therapeutic dose of clenbuterol, with and without exercise, on the contractile activation characteristics of single membrane permeabilized fibres prepared from muscle biopsies. We tested the hypothesis that therapeutic treatment with clenbuterol would not affect muscle fibre function. Unfit Standardbred mares were treated for 8 weeks with; clenbuterol (2.4 microg/kg twice/day, 5 days/week) plus exercise (20 min at 50% VO2(max) 3 d/wk; CLENEX), clenbuterol only (CLEN), or exercise only (EX). Muscle biopsies were taken from the gluteus medius muscle before and after treatment and stored in a glycerol-based solution to prepare permeabilized muscle fibres. The force-pCa relationship for fibres from CLEN horses was steeper (P < 0.05) indicative of greater cooperative interactions within the thin filament, however, fibre sensitivity to Ca2+ was unchanged. In contrast, the steepness of the force-pCa relationship was not changed in fibres from EX and CLENEX horses and Ca2+ sensitivity was also unaffected. Rigor force, activation in the absence of ATP, was not affected by any treatment indicating an approximately equivalent number of participating cross-bridges during activation. The results indicate that a therapeutic dose of clenbuterol to Standardbred horses does not affect the Ca(2+)-activated contractile characteristics of isolated muscle fibres.
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