Breast magnetic resonance imaging: are those who need it getting it?

BACKGROUND

Indications for breast magnetic resonance imaging (mri), a very sensitive but less-specific tool for breast investigation, remain controversial, and accessibility is limited. The purposes of our study were to determine the proportion of breast mri exams performed for various clinical indications, to assess the wait times for breast mri, and to create a list of evidence-based indications for breast mri.

METHODS

The indications for breast mri exams performed in September 2013 at our academic centre were audited. A multidisciplinary meeting held in May 2014 established a list of evidence-based indications for breast mri, after which, in September 2014 and 2015, breast mri exams were re-audited for clinical indications, and pending requests were calculated.

RESULTS

In September 2013, surveillance of women with a prior diagnosis of breast cancer represented 21% of breast mri exams (24 of 113), with preoperative staging representing 18% of exams (20 of 113) and high-risk screening representing 12% (13 of 113). Of pending mri requests, 230 were within the recommended delay period, and 457 exceeded the recommended delay. After elaboration of evidence-based guidelines, repeat audits in September 2014 and September 2015 showed that mri performed for women with a prior breast cancer diagnosis represented 23% (33 of 141) and 7% (10 of 143) of exams respectively, with preoperative staging having declined to 9% (13 of 141) and 11% (16 of 143) of exams, and high-risk screening having increased to 36% (51 of 141) and 46% (66 of 143) of exams. Overall, wait times were improved for all breast mri indications.

CONCLUSIONS

Through multidisciplinary discussion, we actualized a list of breast mri indications, prioritized requests more adequately, and improved wait times.

Recommendations on breast cancer screening and prevention in the context of implementing risk stratification: impending changes to current policies

In recent years, risk stratification has sparked interest as an innovative approach to disease screening and prevention. The approach effectively personalizes individual risk, opening the way to screening and prevention interventions that are adapted to subpopulations. The international perspective project, which is developing risk stratification for breast cancer, aims to support the integration of its screening approach into clinical practice through comprehensive tool-building. Policies and guidelines for risk stratification-unlike those for population screening programs, which are currently well regulated-are still under development. Indeed, the development of guidelines for risk stratification reflects the translational aspects of perspective. Here, we describe the risk stratification process that was devised in the context of perspective, and we then explain the consensus-based method used to develop recommendations for breast cancer screening and prevention in a risk-stratification approach. Lastly, we discuss how the recommendations might affect current screening policies.

The role of community pharmacists in the prevention and management of osteoporosis and the risk of falls: results of a cross-sectional study and qualitative interviews

In a mailed survey and qualitative interviews, it was observed that community pharmacists and public health authorities believe that pharmacists should play a significant role in the prevention and management of osteoporosis and the risk of falls. However, pharmacists acknowledge a wide gap between their ideal and actual levels of involvement.

INTRODUCTION

The aim of this study was to explore perceptions of community pharmacists and public health authorities regarding the role of pharmacists in providing services in relation to osteoporosis and risk of falls and the barriers to providing them.

METHODS

Using a modified five-step version of Dillman's tailored design method, a questionnaire was mailed to a random sample of 1,250 community pharmacists practicing in Montreal (Quebec, Canada) and surrounding areas. A similar questionnaire was sent to public health officers in these regions. Additionally, telephone interviews were conducted with regional and ministry level public health officers.

RESULTS

Of the 1,250 pharmacists contacted, 28 were ineligible. In all, 571 of 1,222 (46.7 %) eligible community pharmacists and all the public health officers returned the questionnaire. Six public health officers (five regional and one at ministry level) were interviewed. Most pharmacists believed they should be involved in screening for osteoporosis (46.6 %) and risk of falls (50.3 %); however, fewer reported actually being involved in such services (17.4 % and 19.2 %, respectively). In their view, the main barriers to providing these services in current practice were lack of time (78.8 %), lack of clinical tools (65.4 %), and lack of coordination with other healthcare professionals (54.5 %). Public health authorities also thought community pharmacists should play a significant role in providing osteoporosis and fall risk services. However, few community pharmacist-mediated activities are in place in the participating regions.

CONCLUSIONS

Although community pharmacists and public health authorities believe pharmacists should play a significant role with regard to osteoporosis and the risk of falls, they acknowledge a wide gap between the ideal and actual levels of pharmacist involvement.

Multimodality breast cancer screening in women with a familial or genetic predisposition

BACKGROUND

Women with a predisposition for breast cancer require a tailored screening program for early cancer detection. We evaluated the performance of mammography (MG), ultrasonography (US), and magnetic resonance imaging (MRI) screening in these women.

PATIENTS AND METHODS

In asymptomatic women either confirmed as BRCA1/2 carriers, or having a greater than 30% probability of being so as estimated by brcapro [Berry D, Parmigiani G. Duke SPORE (Specialized Program of Research Excellence) in Breast Cancer. 1999], we conducted a prospective comparative trial consisting of annual MRI and MG, and biannual US and clinical breast examination. All evaluations were done within 30 days of one another. For each screening round, imaging tests were independently interpreted by three radiologists.

RESULTS

The study enrolled 184 women, and 387 screening rounds were performed, detecting 12 cancers (9 infiltrating, 3 in situ), for an overall cancer yield of 6.5%. At diagnosis, 7 infiltrating cancers were smaller than 2 cm (T1); only 1 woman presented with axillary nodal metastases. All tumours were negative for the human epidermal growth factor receptor 2. Of the 12 cancers, MRI detected 10, and MG, 7; US did not identify any additional cancers. The overall recall rate after MRI was 21.8%, as compared with 11.4% for US and 16.1% for MG. Recall rates declined with successive screening rounds. In total, 45 biopsies were performed: 21 as a result of an US abnormality; 17, because of an MRI lesion; and 7, because of a MG anomaly.

INTERPRETATION

In high-risk women, MRI offers the best sensitivity for breast cancer screening. The combination of yearly MRI and MG reached a negative predictive value of 100%. The recall rate is greatest with MRI, but declines for all modalities with successive screening rounds.

Effectiveness of interventions to improve the detection and treatment of osteoporosis in primary care settings: a systematic review and meta-analysis

This study aims to evaluate the effectiveness of primary care interventions to improve the detection and treatment of osteoporosis. Eight electronic databases and six gray literature sources were searched. Randomized controlled trials, controlled clinical trials, quasi-randomized trials, controlled before-after studies, and interrupted time series written in English or French from 1985 to 2009 were considered. Eligible studies had to include patients at risk (women ≥ 65 years, men ≥ 70 years, and men/women ≥ 50 years with at least one major risk factor for osteoporosis) or at high risk (men/women using oral glucocorticoids or with previous fragility fractures) for osteoporosis and fractures. Outcomes included bone mineral density (BMD) testing, osteoporosis treatment initiation, and fractures. Data were pooled using a random effects model when applicable. Thirteen studies were included. The majority were multifaceted and involved patient educational material, physician notification, and/or physician education. Absolute differences in the incidence of BMD testing ranged from 22% to 51% for high-risk patients only and from 4% to 18% for both at-risk and high-risk patients. Absolute differences in the incidence of osteoporosis treatment initiation ranged from 18% to 29% for high-risk patients only and from 2% to 4% for at-risk and high-risk patients. Pooling the results of six trials showed an increased incidence of osteoporosis treatment initiation (risk difference (RD) = 20%; 95% CI: 7-33%) and of BMD testing and/or osteoporosis treatment initiation (RD = 40%; 95% CI: 32-48%) for high-risk patients following intervention. Multifaceted interventions targeting high-risk patients and their primary care providers may improve the management of osteoporosis, but improvements are often clinically modest.

Impact of a primary care physician workshop on osteoporosis medical practices

SUMMARY

Attendance at a fragility-fractures-prevention workshop by primary care physicians was associated with higher rates of osteoporosis screening and treatment initiation in elderly female patients and higher rates of treatment initiation in high-risk male and female patients. However, osteoporosis management remained sub-optimal, particularly in men.

INTRODUCTION

Rates of osteoporosis-related medical practices of primary care physicians exposed to a fragility-fractures-prevention workshop were compared with those of unexposed physicians.

METHODS

In a cluster cohort study, 26 physicians exposed to a workshop were matched with 260 unexposed physicians by sex and year of graduation. For each physician, rates of bone mineral density (BMD) testing and osteoporosis treatment initiation among his/her elderly patients 1 year following the workshop were computed. Rates were compared using multilevel logistic regression models controlling for potential patient- and physician-level confounders.

RESULTS

Twenty-five exposed physicians (1,124 patients) and 209 unexposed physicians (9,663 patients) followed at least one eligible patient. In women, followed by exposed physicians, higher rates of BMD testing [8.5% versus 4.2%, adjusted OR (aOR) = 2.81, 95% CI 1.60-4.94] and treatment initiation with bone-specific drugs (BSDs; 4.8% vs. 2.4%, aOR = 1.95, 1.06-3.60) were observed. In men, no differences were detected. In patients on long-term glucocorticoid therapy or with a previous osteoporotic fracture, higher rates of treatment initiation with BSDs were observed in women (12.0% vs. 1.9%, aOR = 7.38, 1.55-35.26), and men were more likely to initiate calcium/vitamin D (5.3% vs. 0.8%, aOR = 7.14, 1.16-44.06).

CONCLUSIONS

Attendance at a primary care physician workshop was associated with higher rates of osteoporosis medical practices for elderly women and high-risk men and women. However, osteoporosis detection and treatment remained sub-optimal, particularly in men.

Better adherence to antihypertensive agents and risk reduction of chronic heart failure

AIMS

Antihypertensive (AH) agents have been shown to reduce the risk of major cardiovascular events including chronic heart failure (CHF). However, the impact of changes in patterns of AH agents use on CHF is unknown. Our objective was to estimate to which different patterns of AH agent use is associated with the occurrence of CHF in a population-based study.

METHOD AND RESULTS

A cohort of 82 320 patients was reconstructed using the Régie de l'assurance maladie du Québec's databases. Patients were eligible if they were between 45 to 85 years of age, had no indication of cardiovascular disease and were newly treated with AH therapy between 1999 and 2004. A nested case-control design was used to study the occurrence of CHF. Every case of CHF was matched for age and duration of follow-up to a maximum of 15 randomly selected controls. Adherence level was reported as a medication possession ratio. Conditional logistic regression models were used to estimate the rate ratio (RR) of CHF adjusting for different covariables. The mean patient age was 65 years, 37% were male, 8% had diabetes, 19% had dyslipidaemia and mean time of follow-up at 2.7 years. High adherence level (95%) to AH therapy compared with lower adherence level (60%) was associated with an additional reduction of CHF events (RR: 0.89; 0.80-0.99). Risk factors for CHF were being on social assistance, diabetes, dyslipidaemia, higher chronic disease score and developing a cardiovascular condition during follow-up.

CONCLUSION

Our study suggests that a better adherence is associated with a significant risk reduction of CHF. Adherence to AH therapy needs to be improved to optimize benefits.

Developing a Liaison Role for Pharmacists in a Family Medicine Clinic

Objective:

To develop a pharmacist liaison service in a family medicine teaching clinic in order to optimize and facilitate community pharmacists' interventions.

Target groups:

Community pharmacists involved in the care of patients registered at the family medicine clinic (FMC) of Cité de la Santé de Laval and clinical pharmacists working at this clinic.

Activities:

The FMC is a medical teaching clinic located in a general care hospital. The FMC operates as a multidisciplinary group of GPs, nurses and pharmacists providing care to enlisted patients. Due to their clinical experience, proximity to the medical team and direct access to FMC patients' charts, FMC pharmacists (FMC-PH) are in a key position to support community pharmacists (COM-PH) in order to optimize the quality of pharmaceutical care dispensed to their common patients. The liaison pharmacist service was created within a larger study of COM-PH interventions and their impact on medication when receiving a doctor request for medication profile analysis and a standard prescription or a prescription enriched with additional clinical information. Forty-nine COM-PH interested in participating in the larger study attended one of 3 workshops offered by pharmacy residents, FMC-PH and a physician. Information on the clinic and the new service of liaison as well as case studies on medication adjustment and laboratory monitoring were presented and discussed. A decision aid tool was also provided to participants. A FMC-PH is available from Monday to Friday (9 a.m. to 4 p.m.) to answer questions by telephone from COM-PH directly related to FMC's patients' care and links with the medical team when necessary. Liaison tasks were added to other clinical duties and responsibilities of the FMC-PH. Communications with COM-PH were documented by FMC-PH between November 2007 and April 2008.

Deliverables:

Fifty-eight communications involving 27 COM-PH and 49 patients have been documented. Among 78 drug-related issues discussed with FMC-PH, the most frequent were obtaining results or suggesting laboratory monitoring (35%), discordance between pharmacy medication chart and FMC chart (18%), dose too high (8%), additional medication needed (8%), dose too low (5%) and inappropriate medication. Among the 93 actions taken by FMC-PH in response to contact with COM-PH, the most frequent were transferring additional laboratory results (29%) or additional information related to treatment (22%) to COM-PH, transferring new information and recommendations to the medical team via case discussion with treating physician and/or writing a note in the FMC patient's chart (22%), revising medication history (14%) and correcting patient's medication profile in the FMC chart (11%). The mean time per action was 9.5 ± 8.9 minutes.

Conclusion:

The liaison pharmacist service was used regularly by the community pharmacists and was easily integrated in the FMC-pharmacists' tasks. Community pharmacists' calls resulted in additional information or correction of available information to the FMC team in 33% of cases. Community pharmacists were very interested in obtaining laboratory results and additional clinical information to optimize their patient follow-up. This model of liaison succeeded in increasing collaboration and improving flow of information between pharmacists.

Persistence and determinants of statin therapy among middle-aged patients for primary and secondary prevention

AIMS

Statins have been shown to significantly reduce morbidity and mortality in patients with coronary artery disease (CAD), and also in patients with dyslipidaemia when statins are taken regularly. Middle-aged patients have the highest level of forecasting benefit and little is known about persistence rate of these therapies in a real-life setting. The objective was to evaluate the persistence rate of middle-aged patients initiating a statin therapy and its relation with several determinants for primary and secondary prevention.

METHODS

A cohort was reconstructed using the RAMQ databases. All patients aged 50-64 years-old who received at least one statin prescription between 1 January, 1998 and 31 December, 2000 for a new intention of treatment for dyslipidaemia were included in the cohort and followed up until 30 June, 2001. The date of the first prescription of statin was defined as the index date. There were 4316 patients in the secondary prevention (CAD diagnosis) and 13,642 patients in primary prevention cohort. The cumulative persistence rate was estimated using Kaplan-Meier, and Cox regression models were used to estimate the hazard ratio of ceasing statins.

RESULTS

We found that persistence with statins had fallen to 71% after 6 months of treatment, and had declined to 45% after 3 years in the secondary prevention cohort; the corresponding figures were 65% and 35% in the primary prevention cohort. Our results suggest that patients with dyslipidaemia in primary prevention compared with those in secondary prevention (HR: 1.18; 1.11-1.25) are less likely to be persistent. Patients with other cardiovascular risk factors such as age (HR: 0.99; 0.98-0.99), diabetes (HR: 0.84; 0.79-0.90), hypertension (HR: 0.76; 0.72-0.80) were most likely to be persistent with statins. We observed lower persistence in patients who have used the greatest number of pharmacies and prescribing physicians.

CONCLUSION

This analysis indicates that barriers to persistence occur early in the therapeutic course. Overall persistence with statins is low, and particularly among patients with few other cardiovascular risk factors.

Health-related quality of life with coronary heart disease prevention and treatment

Estimating the net benefits of dyslipidemia treatment is limited by the lack of comprehensive and standardized information on the preference for dyslipidemia and coronary heart disease. In a hospital-based study, we measured the health-related quality of life (HRQOL) of healthy participants without dyslipidemia (n = 307) and with dyslipidemia (n = 251) and patients with coronary heart disease (n = 320). Compared to the healthy participants without dyslipidemia, those with dyslipidemia reported lower adjusted mean scores on the Rating Scale (-2.8 points, P = 0.02) and the SF-36 General Health Scale (-3.3 points, P = 0.02). No differences were observed on the Time Trade-off and the Standard Gamble Scales. Coronary patients reported lower scores on all preference scales and most SF-36 scales. The causes of the small but real reduction in HRQOL reported by dyslipidemic individuals should be identified in order to optimize the net benefits of lipid therapy.

Variation over time of the effects of prognostic factors in a population-based study of colon cancer: comparison of statistical models

The authors compare the performance of different regression models for censored survival data in modeling the impact of prognostic factors on all-cause mortality in colon cancer. The data were for 1,951 patients, who were diagnosed in 1977-1991, recorded by the Registry of Digestive Tumors of Côte d'Or, France, and followed for up to 15 years. Models include the Cox proportional hazards model and its three generalizations that allow for hazard ratio to change over time: 1) the piecewise model where hazard ratio is a step function; 2) the model with interaction between a predictor and a parametric function of time; and 3) the non-parametric regression spline model. Results illustrate the importance of accounting for non-proportionality of hazards, and some advantages of flexible non-parametric modeling of time-dependent effects. The authors provide empirical evidence for the dependence of the results of piecewise and parametric models on arbitrary a priori choices, regarding the number of time intervals and specific parametric function, which may lead to biased estimates and low statistical power. The authors demonstrate that a single, a priori selected spline model recovers a variety of patterns of changes in hazard ratio and fits better than other models, especially when the changes are non-monotonic, as in the case of cancer stages.

Comparing the psychometric properties of preference-based and nonpreference-based health-related quality of life in coronary heart disease. Canadian Collaborative Cardiac Assessment Group

A cross-sectional survey (n = 878) was conducted to compare the psychometric properties of three preference-based and one nonpreference-based health-related quality of life measures among healthy subjects with and without treatment for dyslipidemia and/or hypertension and patients with coronary heart disease (CHD). All measures were stable over a 3 to 6 week period. Compared to the Time Trade-off (TTO) and the Standard Gamble (SG), the Rating Scale (RS) correlated with the SF-36 Health Survey most highly. In contrast to the SF-36 General Health Perception (GHP), the SF-36 Physical Component scale and the RS, the TTO and SG were less able to discriminate CHD patients with various levels of physical disability. Only the SF-36 GHP subscale and the RS were able to differentiate healthy participants from participants receiving dyslipidemia and/or hypertension treatment. Neither the SF-36 Physical or Mental Component scales were able to discriminate these two groups. Overall, these results suggest that unlike the RS, the TTO and the SG, as administered in this study, may not be sufficiently sensitive to measure the impact of primary cardiovascular disease prevention strategies on the health-related quality of life of the participants.

Conventional and chained standard gambles in the assessment of coronary heart disease prevention and treatment. Canadian Collaborative Cardiac Assessment Group

The authors compared the abilities of descriptive and valuational health-related quality-of-life measures to discriminate healthy participants (n=39) from those on diets for dyslipidemia (n=35) and angina patients (n=30). On the rating scale, the time tradeoff, and the General Health Perception subscale of the SF-36 Health Survey, the participants with dyslipidemia or angina reported lower mean scores than the healthy participants. No differences were detected between these groups on conventional or chained standard gamble (SG) scales. The distribution of the conventional and the chained SG scores was very skewed, with the vast majority of scores being equal or very close to the maximum score. It is concluded that in this study the discriminant ability of the chained SG was comparable to that of the conventional SG and inferior to descriptive and non-risky valuational scaling techniques. This may be explained by the distortion of probabilities, by a misunderstanding of the SG chained assessment, and by a strong certainty effect.

Level of suspicion of a mammographic lesion: use of features defined by BI-RADS lexicon and correlation with large-core breast biopsy

OBJECTIVE

To determine whether the categories defined in the Breast Imaging Reporting and Data System (BI-RADS) are useful predictors of malignancy and to assess their positive predictive value.

PATIENTS AND METHODS

A retrospective study was undertaken from July 1, 1994, to June 30, 1995. Of 568 abnormal mammograms for which largecore biopsy was recommended, 495 were available for review. The mammographic features of the lesions, as defined by the BI-RADS lexicon, were used to assess the level of suspicion. The lesions were classified as "probably benign," "suspicious" or "highly suggestive of malignancy." These diagnostic impressions were then correlated with the histologic diagnosis made after core biopsy.

RESULTS

The diagnostic impressions before core biopsy were as followed: 16 (3%) benign lesions, 397 (80%) suspicious lesions and 82 (17%) lesions highly suggestive of malignancy. All benign lesions remained in the same category after core biopsy, whereas, of the suspicious lesions, 91% were diagnosed as benign, only 4% as malignant, and the other 5% as atypical hyperplasia. Among the lesions highly suggestive of malignancy according to the BI-RADS lexicon, 54% were found to be malignant at core biopsy.

CONCLUSION

The BI-RADS lexicon is helpful in discriminating between lesions that are probably benign and probably malignant from the mammographic features. However, the rate of malignancy in the "suspicious" category is low.

Pseudoaneurysm of the proper hepatic artery with duodenal fistula appearing as a late complication of blunt abdominal trauma

Posttraumatic pseudoaneurysms of the hepatic artery are rare and usually occur as a complication of open abdominal trauma. Even less common is the coexisting presence of enteric fistulization. We report a patient with upper gastrointestinal hemorrhage occurring 3 years after blunt abdominal trauma resulting from a pseudoaneurysm of the proper hepatic artery with duodenal fistulization. The patient was treated successfully by ligation of the proper hepatic artery and closure of the duodenal opening.

Drug-related segmental colitis: angiographic findings

We report a case of drug-related segmental colitis in a 70-year-old woman with no thromboembolic risk factor. Mesenteric angiography showed multiple stenoses and occlusions of the distal arterial circulation in the sigmoid and descending colon. These observations support the hypothesis of an ischemic origin for this type of colitis.

Liver angiomyolipoma: classic and unusual presentations

Two cases of liver angiomyolipoma (AML) are presented. The first case has the classical imaging findings previously reported. The second case has no fat content on the various imaging modalities. AML should probably be included in the differential diagnosis of any hypervascular lesion of the liver. Preoperative diagnosis with core biopsy is possible.

CT of the portal vein after portacaval shunt with arterialization

OBJECTIVE

Our goal was to assess the state of the portal vein in cirrhotic patients treated with a portacaval shunt associated with an arterialization of the portal vein.

MATERIALS AND METHODS

We reviewed the follow-up CT of 23 patients treated by portacaval shunt with arterialization of the portal vein.

RESULTS

Five patients demonstrated an aneurysm of the portal vein. Follow-up studies revealed progression of the aneurysm and development of a mural thrombosis in four patients. The thrombosed portal vein was calcified in three patients. One patient demonstrated a dilatation of the saphenous vein graft in addition to the portal vein aneurysm. Only one of the five patients was symptomatic, presenting with ascites, dilatation of intrahepatic biliary ducts, and jaundice secondary to the compression of hilar structures by the huge portal vein.

CONCLUSION

Aneurysm of the portal vein following portacaval shunt associated with arterialization of the portal vein is not a rare complication.

Dynamic CT in pancreatic lymphoma

We retrospectively reviewed the dynamic CT examinations of eight patients with pancreatic lymphoma. Four tumors were rounded masses with well-defined contours, four were more infiltrating lesions. The median cross-sectional diameter of the tumors was 6 cm (range 2.5-12 cm). At dynamic CT, the tumors were hypodense (n = 8) and somewhat heterogeneous (n = 6). Additional features were enlarged lymph nodes, 1-3 cm in diameter (n = 5), dilatation of the biliary tract and pancreatic duct (n = 5), abnormalities in the fat around the celiac trunk and/or the superior mesenteric artery (n = 4), and venous stenosis or occlusion (n = 7). The CT findings of pancreatic lymphoma are more various than has been previously reported. Findings such as small tumor size, well-defined contours, tumor heterogeneity, pancreatic duct dilatation, and venous invasion may be seen. Pancreatic lymphoma cannot be reliably distinguished from pancreatic carcinoma by CT findings alone.

Capsule and mosaic pattern of hepatocellular carcinoma: correlation between CT and MR imaging

Computed tomography (CT) was compared with magnetic resonance (MR) imaging in depicting the capsule and the mosaic pattern of hepatocellular carcinoma in 34 patients. The kappa statistic was used to compare results from both modalities. For the detection of the capsule, there was a substantial agreement beyond chance between late enhanced CT (more than 5 min after dynamic CT) and MR imaging (kappa = 0.76). Late enhanced CT and MR imaging had almost perfect agreement for the demonstration of the mosaic pattern (kappa = 0.85). These agreements were better than the agreements between unenhanced CT and MR imaging or between early enhanced CT and MR imaging. These results suggest that late enhanced CT compares favorably with MR imaging in depicting the capsule and the mosaic pattern of hepatocellular carcinoma.

Focal nodular hyperplasia in association with spontaneous intrahepatic portosystemic venous shunt

We report a case of focal nodular hyperplasia in an adolescent with a spontaneous intrahepatic portosystemic venous shunt. Diagnosis was established by duplex and color Doppler ultrasound, computed tomography, magnetic resonance imaging, and histology. This association further supports the hypothesis that focal nodular hyperplasia is a response to a preexisting vascular abnormality.

Epithelioid hemangioendothelioma of the liver: MR and CT findings

The MR imaging features in five patients with hepatic epithelioid hemangioendothelioma (EHE) were correlated with CT and pathologic findings. Two hemangioendotheliomas appeared as multiple nodular lesions with a predominantly peripheral location in the liver. In three more extensive cases, the tumors formed confluent peripheral lesions with macroscopic invasion of portal or hepatic veins (n = 3), signs of portal hypertension (n = 3), and nodular hypertrophy of uninvolved liver (n = 2). These findings, suggestive of EHE, were well demonstrated by MR imaging and CT. The internal architecture of the tumors was clearly depicted on T2-weighted MR images. Viable tumor peripheries appeared moderately hyperintense relative to liver. The center of the tumors consisted of one or several concentric zones. Hyperintense central zones were composed of loose, edematous connective tissue. Hypointense zones contained mainly coagulation necrosis, calcifications, and scattered hemorrhages. Except for the presence of calcifications, the internal architecture of EHE was better defined by MR imaging than by CT.

Male infertility associated with round-headed acrosomeless spermatozoa

The properties of spermatozoa with round head syndrome in four unrelated patients are reported. The findings were as follows: (1) Electron microscopy demonstrated that all spermatozoa lacked an acrosome and postacrosomal sheath. (2) Acrosin activity was only 1% to 6% of that found in sperm obtained from fertile donors. (3) Phospholipase A2 activity was not significantly different from that of spermatozoa from donors of unknown fertility. (4) Electrophoresis of whole sperm extracts revealed deficiencies in major protein bands. (5) The round-headed spermatozoa failed to bind or penetrate the vitellus in the egg penetration test. (6) The rates of chemically induced nuclear chromatin decondensation of round-headed spermatozoa suggest that the acrosome content is not involved in this process.

Perioperative myocardial infarction with coronary artery surgery: diagnosis, incidence and consequences

Perioperative myocardial infarction is a potential consequence of coronary artery bypass surgery. The diagnosis is difficult due to multiple factors including postoperative chest discomfort, serum enzyme elevations and nonspecific electrocardiographic changes. No one test is reliable, but a combination of electrocardiogram, MBCK serum enzyme analysis and technetium pyrophosphate scanning should increase the probability of correct diagnosis. Using this method, the incidence of perioperative myocardial infarction in this study was six out of 100. Left ventricular function in the early postoperative period was adversely affected by perioperative myocardial infarction with a reduction in left ventricular ejection fraction (63 +/- 9% preoperative to 54 +/- 12% postoperative; P less than 0.05), whereas left ventricular ejection fraction was unchanged in the absence of perioperative myocardial infarction. The long term left ventricular function, however, appears to recover, and at two years after surgery there was no difference in rest or exercise left ventricular function between patients who suffered perioperative myocardial infarction versus those who did not. All patients with perioperative myocardial infarction survived to be discharged from hospital, and all returned for follow-up at two years. Their functional and work status was no different from those without perioperative myocardial infarction. This would suggest that, if patients survive a perioperative myocardial infarction, their long term functional status is no different from those patients without perioperative myocardial infarction.

Altered Gene Expression during Auxin-Induced Root Development from Excised Mung Bean Seedlings

Changes in the pattern of protein synthesis and in the translatable mRNA population have been examined during auxin-induced root development from excised mung bean seedlings. Several proteins, predominantly of low molecular weight and high pI, as shown by two-dimensional polyacrylamide gel electrophoresis, are synthesized specifically by auxin-treated tissue. These auxin-induced proteins appear between 6 and 12 hours of auxin treatment, reach a maximum at 24 hours, and decline at 48 hours. Untreated seedlings (placed in Hoagland solution), known to produce small number of roots at the cut end probably due to endogeneous auxin accumulated at the cut end through basipetal transport, show low level synthesis of auxin-specific proteins. Antiauxin treatment that completely inhibits auxin-induced rooting also prevents the appearance of auxin-induced proteins. The induction of a group of three to four proteins appears to be specific to antiauxin treatment. In vitro translation of mRNA from auxin-treated tissue, but not of mRNA from antiauxin-treated tissue, yields several polypeptides of low molecular weight and high pI. Since the auxin-induced proteins precede root development and are synthesized transitorily, it is likely that they play some regulatory role during the initiation of root development. The result show that auxin-induced root formation involves altered gene expression.

Comparative effect of ANF and various diuretics on isolated nephron segments

The effect of the synthetic form of ANF 0.1 to 10 microgram/ml (peptide 101-126), a diuretic and natriuretic peptide isolated from rat heart atria, on the metabolism of dog and rat kidney tubules was studied in vitro and compared to that of furosemide (0.1 to 1 mM), hydrochlorothiazide (0.5 mM) or amiloride (0.1 mM). In order to pinpoint eventual site(s) of ANF action along the nephron, proximal tubules, thick ascending limbs and papillary collecting ducts were isolated from dog kidneys as well as proximal tubules from rat kidneys. The substrate uptake (O2, lactate, glutamine, glucose) and production of metabolites (glutamate, ammonium, alanine, glucose) by these nephron segments were measured in absence or presence of the diuretic agents or the vehicle for ANF (acetate 1 mM). The total ATP turnover and the contribution of identified metabolic pathways for this turnover was calculated. It was expected that a molecule with diuretic properties reducing the permeability of cell membranes to NaCl would secondarily reduce the Na-K-ATPase activity, and therefore the oxygen and substrate utilization by affected cells. It was shown: that each nephron segment used presented the expected specific metabolic characteristics; that furosemide markedly inhibits the oxidative metabolism of thick ascending limbs; that acetate (the vehicle used for ANF) displaces the oxidation of glutamine and lactate in nephron segments with aerobic metabolism; that ANF had no effect on the metabolism of the studied segments despite the presence of specific c'GMP-generating receptors in the distal nephron. It is concluded that ANF must exert its natriuretic effect by a mechanism different from that of classical diuretics.

ATP turnover and renal response of dog tubules to pH changes in vitro

In vivo the dog kidney responds to metabolic or respiratory acidosis by a marked increment of its ammonia production (expressed per 100 milliliters glomerular filtration rate). This phenomenon is related to a switch from metabolic utilization of nonammoniagenic (lactate) to ammoniagenic (glutamine) substrates to support ATP turnover in the proximal tubules. We have proposed that in vivo the maximum activity of the ammoniagenic process is fixed by the ATP turnover in this segment of the nephron. The maximal glutamine metabolism is reached when 100% of this turnover is supported by glutamine metabolism. We have studied how these concepts apply to the adaptation of glutamine metabolism and ammonia production to a low pH in vitro using proximal tubules of dogs incubated when one (lactate or glutamine) or several (glutamine plus lactate or plus palmitate) substrates are provided. At pH 7.4 glutamine alone supports already 71-76% of the tissue ATP turnover (minimal and maximal values). With acidification this fraction rises to nearly 87-94%, but this increases only modestly the ammonia production. Reducing the ATP turnover with ouabain at pH 7.4 decreases the absolute glutamine utilization, which now supports only 45-50% of the ATP turnover. Again acidification increases this fraction to 90-99%. Addition of lactate with glutamine displaces part of the glutamine metabolized, but greatly stimulates the synthesis of alanine. Fatty acids depress ammonia production and blunt the tissue response to acidification. Gluconeogenesis from lactate is minimally influenced by incubation pH. It is concluded that the ATP turnover limits the metabolism of glutamine by proximal tubules in vitro as in vivo in the dog, and that the response to acidification is small in vitro because of the absence of alternative substrates.

Patterns of protein synthesis during the germination of pea axes, and the effects of an interrupting desiccation period

As germination of axes of Pisum sativum L. seeds progressed, profound quantitative and qualitative changes occurred in the patterns of protein synthesis. This was shown by fluorography of gels following two-dimensional polyacrylamide gel electrophoresis separation of [(35)S]methioninelabelled proteins. The effects of desiccation during germination on these in-vivo protein-synthesis patterns were followed. Desiccation differentially affected the synthesis of proteins. Usually, however, upon rehydration following desiccation the types of proteins being synthesized were recognizable as those synthesized earlier during imbibition of control, once-imbibed axes: seeds imbibed for 8 h, and then dried, did not recommence synthesis of proteins typical of 8-h-imbibed control seeds, but rather of 4-h-imbibed control seeds. Seeds imbibed for 12 h, and then dried and rehydrated, synthesized proteins typical of 4-h-and 8-h-control seeds. Thus drying of germinating pea axes caused the proteinsynthesizing mechanism to revert to producing proteins typical of earlier stages of imbibition. Drying during germination never caused the seed to revert to the metabolic status of the initial mature dry state, however.

Fluorometry of selenium in serum or urine

This fluorometric procedure for determining selenium in human serum or urine is sensitive (requiring only 0.4 mL of sample), accurate, simple, and can be performed on several samples concurrently. Using this technique, we found a mean selenium concentration in the serum of normal Canadian men of 142.9 (SD 16.1) micrograms/L. The mean urinary excretion rate was 124.5 (SD 76.0) micrograms/day.

Fluorometry of selenium in serum or urine

This fluorometric procedure for determining selenium in human serum or urine is sensitive (requiring only 0.4 mL of sample), accurate, simple, and can be performed on several samples concurrently. Using this technique, we found a mean selenium concentration in the serum of normal Canadian men of 142.9 (SD 16.1) micrograms/L. The mean urinary excretion rate was 124.5 (SD 76.0) micrograms/day.