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R J Brenner

Publications and source records attributed to R J Brenner.

At least 55 records · Page 3Linked to original sources
PubMed1995

The mammography audit: a primer for the mammography quality standards act (MQSA).

The medical audit of a mammography practice is a recognized method for evaluating mammography and the accuracy of mammographic interpretation [1-4]. As such, portions of the audit will become integral to the quality assurance activities of every mammography practice under the Mammography Quality Standards Act (MQSA) of 1992, administered by the Food and Drug Administration (FDA). The FDA Interim Rules, which became effective October 1, 1994, state that "each facility shall establish a system for reviewing outcome data from all mammography performed, including follow-up on the disposition of positive mammograms and correlation of surgical biopsy results with mammogram reports" [5]. It is expected that the proposed final rules, due to be released for public comment in 1995, will require collection of additional data for medical audits (public meeting of the National Mammography Advisory Committee, May 3, 1994). Although most mammography practices are now collecting clinical outcomes data on abnormal mammographic examinations, very few have established an organized and deliberate system of data collection necessary for a more complete mammography audit [6]. A detailed discussion of and recommendations for such an audit were recently published as part of the Quality Determinants of Mammography Guideline by the Agency for Healthcare Policy and Research (AHCPR) [7]. As members and consultants on the multidisciplinary panel that produced the guideline, we offer the following review of the various elements, definitions, and processes of the mammography audit. This is intended as a primer for all radiologists who will be performing some of the same audit activities for the MQSA.

Female↗
PubMed1995

Current management of ductal carcinoma in situ.

Ductal carcinoma in situ represents a biologically and histologically heterogeneous group of lesions characterized by the proliferation of neoplastic epithelial cells confined to the ducts of the breast. Before screening mammography, ductal carcinoma in situ was considered uncommon; patients were usually diagnosed by a breast mass or bloody nipple discharge, and their treatment was mastectomy. Today it represents 20% to 30% of mammographically detected breast cancers and 10% to 15% of all diagnosed breast cancers in the United States. The invariable progression of this cancer to invasive breast cancer requiring mastectomy has been challenged, but because most patients have been treated with mastectomy, knowledge about ductal carcinoma in situ is limited and primarily based on retrospective data. Further insight will emerge from randomized prospective studies that are near completion. Currently available data indicate that breast-conserving treatments are valid alternatives to mastectomy for most patients with this disease.

Breast Neoplasms↗
PubMed1994

Breast cancer evaluation. Medical-legal and risk management considerations for the clinician.

The legal consequences for physicians involved in the treatment of patients who are at risk for or have developed breast cancer are many. The law of negligence, which is concerned with departures from reasonable standards of conduct, govern most of the cases that come to legal attention. Several other torts or civil infractions, however, may be applicable to such practices. Lessons learned from both trial and appellate decisions rendered in this field offer some guidance to avoid untoward medical and legal consequences.

Breast Neoplasms↗
PubMed1994

Behavioral and physiological resistance to insecticides in the German cockroach (Dictyoptera: Blattellidae): an experimental reevaluation.

Although physiological resistance to pesticides has been demonstrated in German cockroaches, Blattella germanica (L.), behavioral resistance has not been shown clearly. To test for the possible development of behavioral resistance, choice-test experiments were done to determine whether adult males and females from physiologically resistant and susceptible strains differed in avoidance of three emulsifiable formulations (chlorpyrifos, cypermethrin, and chlordane). Physiological resistance was verified by estimation of LC50s. Within 6 h, each cockroach chose between an untreated and a treated harborage. In the resistant strain, both sexes avoided harborages treated with cypermethrin and survived the choice tests, but more females than males avoided harborages treated with chlorpyrifos and survived. In the susceptible strain, neither sex avoided harborages treated with cypermethrin or chlorpyrifos, and most died. The physiologically resistant strain was more resistant to chlorpyrifos and cypermethrin than was the susceptible strain, with females generally having higher LC50s. However, in choice tests with chlordane in which physiological resistance levels were similar between the strains, the strains did not differ in avoidance of treated harborages or survivorship. Avoidance of treated harborages may be facilitated by high levels of physiological resistance, but we detected no behavioral resistance traits. High levels of physiological resistance permitted cockroaches to absorb an amount of pesticide that led to detection and subsequent avoidance of treated harborages. Results of our study suggest that previous research on insects has not demonstrated the evolution of stimulus-dependent behavioral resistance in field populations exposed to pesticides.

Animals↗
PubMed1994

Spontaneous regression of interval benign cysts of the breast.

PURPOSE: To evaluate the natural history of nonpalpable interval breast cysts detected at mammography and diagnosed at sonography in an asymptomatic female population. MATERIALS AND METHODS: The imaging records of 5,000 consecutive patients (aged 35-77 years [mean, 51 years]) seen in one breast center over a 6-month period were reviewed. Serial studies of those patients with documented evidence of interval benign breast cysts were evaluated for the subsequent course of such lesions with regard to regression, stability, or enlargement seen at mammography. RESULTS: Interval cysts were found in 53 patients (68 cysts), approximately 1% of the studied population. More than half of these lesions spontaneously regressed in 1 year, most of them completely. By 2 years, nearly two-thirds had regressed. By 5 years, only 12% of the lesions had not shown regression. CONCLUSION: Interval breast cyst formation is not uncommon, and most of these benign lesions will undergo spontaneous regression or remain stable. Further intervention is not required for interval benign cysts.

Adult↗
PubMed1994

Isolation of the 36-kD German (Blattella germanica) cockroach allergen using fast protein liquid chromatography.

Cockroach allergens have been established as important sensitizing agents in the induction of asthma. In the present investigation, we identified a 36-kD allergen from German cockroach (Blattella germanica) using fast protein liquid chromatography that reacted in the Bla g II monoclonal assay developed by Pollart et al. Defatted whole body German cockroaches were extracted in phosphate-buffered saline and fractionated using gel filtration (Superdex 75) and anion exchange (MonoQ) chromatography. The 36-kD allergen was isolated from this enriched allergen preparation by excision from modified preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels, electroelution, dialysis and lyophilization. SDS-PAGE/Western immunoblot analysis using a serum pool of cockroach-sensitive individuals revealed a single band. The lyophilized 36-kD allergen was then analyzed for amino acid composition and digested for peptide amino acid sequencing.

Allergens↗
PubMed1994

Breast MR imaging. An analysis of its role with respect to other imaging and interventional modalities.

The history of breast imaging has focused on the role of dedicated mammography, with its unique ability to provide exquisite contrast and resolution. The dual challenge of breast imaging--public health screening and diagnosis--requires unparalleled considerations of radiation dose and cost, and has prompted the development of other technologies that have failed to replace but have often defined ancillary roles to mammography. The role of breast MR imaging must be measured by these standards, and requires critical appraisal of both its unique contributions and practical limitations.

Breast↗
PubMed1993

Identification of cockroach aeroallergens from living cultures of German or American cockroaches.

The Air Sentinel and polytetrafluoroethylene (PTFE) membranes were used to capture airborne particles over living colonies of German or American cockroaches. Silver-stained SDS-PAGE gels revealed protein bands at 80, 55, 36, and several bands below the 33-kD marker. SDS-PAGE/immunoblots of PTFE eluates from German cockroach colonies incubated with serum from cockroach-sensitive individuals revealed IgE-binding bands with apparent molecular weights of 36 and 80 kD. Only the 36-kD allergen and allergens below the 33-kD marker were evident in the American PTFE eluate. ELISA analysis with a monoclonal antibody assay identified the presence of both Bla g I and Bla g II in the German PTFE eluate. No Bla g I or Bla g II could be identified in the American PTFE eluate. These studies demonstrate that in addition to Bla g I and Bla g II, several other aerosolized allergens become airborne over cockroach colonies and may be important in the environment where cockroaches are abundant.

Air Pollution↗
PubMed1993

Thallium scintigraphy in the evaluation of mass abnormalities of the breast.

Palpable mass abnormalities of the breast are often difficult to evaluate mammographically, especially in patients with fibrocystic change and dense breasts. The current study evaluates 201TI scintigraphy as a potential test in detecting malignancy and in differentiating malignant from benign masses. Eighty-one female patients underwent thallium scintigraphy of the breast because of palpable breast masses. An additional 30 females with no palpable breast abnormalities were also studied using 201TI. Of 44 patients with palpable breast carcinomas, 42 carcinomas (96%) were detected using 201TI scintigraphy. Three of three patients had other primary breast malignancies that were also detected. In contrast, 19 patients with palpable breast abnormalities shown on biopsy to be benign fibrocystic disease processes were not detectable on thallium studies. Of two patients with fat necrosis, none were detectable. Three of 13 patients had adenomas of the breast (23%) that were detected. The three detectable adenomas were all highly cellular. The smallest detectable carcinoma was an adenocarcinoma measuring 1.3 x 1.1 x 0.9 cm. Thallium-201 scintigraphy of palpable breast lesions is an effective test for evaluation of palpable masses. Sensitivity for detection of malignant masses greater than 1.5 cm is high. Highly cellular adenomas, however, may demonstrate significant 201TI uptake. Benign fibrocystic disease is not detectable with thallium scintigraphy. Thallium scintigraphy of breast lesions is an effective means of differentiating benign from malignant lesions.

Adenocarcinoma↗
PubMed1992

Evolving medical-legal concepts for clinicians and imagers in evaluation of breast cancer.

The past decade has seen an intense focus on the evaluation of American women for the detection and diagnosis of breast cancer. A concomitant increase in lawsuits filed for delay in diagnosis of breast cancer has occurred, creating consternation in the medical community. Efforts in responding to this public health challenge, comprised by fear of legal reprisal, may be supported by careful and deliberate planning that incorporates risk management principles and an understanding of different goals to be attained with consequent medical and legal responsibilities.

Breast Neoplasms↗
PubMed1992

Carbon dioxide released from human skin: effect of temperature and insect repellents.

Measurement with an infrared analyzer of CO2 given off by the hands of human volunteers under laboratory conditions showed that they continuously produced CO2 at the rate of 1.0-1.8 ml/h. Increased production of CO2 was observed with increase in temperature for all subjects. Treatment of subjects with three insect repellents or ethanol resulted in a short-term drop in CO2 production, after which it returned to pretreatment levels. Olfactometer studies showed no correlation between the amount of CO2 produced by hands and the attractancy of the subjects to host-seeking female Ae. aegypti (L.). The supplemental addition of five times the amount of CO2 given off by the hands did not affect attractancy of subjects to mosquitoes. The amount of CO2 released by hands is negligible compared to ambient levels of 300 ppm, and it is unlikely to be attractive at this level of release by itself.

Animals↗
PubMed1992

Medicolegal aspects of breast imaging.

The response to the public health challenge of screening women in this country for breast cancer is a goal to which all radiologists should direct their efforts. The decision to perform screening procedures, diagnostic procedures, or both will vary with the individual circumstances of one's practice. Careful planning and attention to certain parameters regarding such different types of practices will provide for a satisfying medical practice that is consistent with a sound risk-management profile. While no practice can be considered insulated from legal redress, physicians should not fear the legal consequences of appropriate and reasonable breast imaging service.

Breast Neoplasms↗
PubMed1991

Seasonality of peridomestic cockroaches (Blattoidea: Blattidae): mobility, winter reduction, and effect of traps and baits.

Populations of smokybrown cockroaches, Periplaneta fuliginosa (Serville), and Eurycotis floridana (Walker) were studied to compare mobility and population size between fall 1985 and spring 1986 seasons at site A, and to assess the effect of a combination of traps and baits at site B in northcentral Florida. Adult smokybrown cockroaches were more mobile in the spring than in the fall; a similar trend for E. floridana adults was not significant. Overall population levels were reduced after winter by approximately 73%. No significant shift in spatial distributions of nymphs occurred, but adult distribution changed from a predominance in palms (fall) to hardwood trees with tree holes (spring), suggesting that this habitat offers better survival during winter. Removal of cockroaches by trapping at site B, followed by a single application of dry distiller's grain containing 0.5 chlorpyrifos, reduced expected population levels (based on site A data) by 90% measured at 6 mo after treatment. These data refute the hypothesis that an increase in numbers of cockroaches infesting homes in the fall is due to an increase in mobility. Instead, the results suggest that population size and proximity of principal habitats to the home are probably responsible for domestic infestations in the fall. Use of traps, baits, or both at these foci significantly reduce populations over an extended period.

Animals↗