The Resident Assessment Instrument (RAI): promise and pitfalls

The nasal bioavailability of oxymorphone HCI was determined. Rats were surgically prepared to isolate the nasal cavity, into which a solution of oxymorphone was administered. A reference group of rats was administered oxymorphone HCl intravenously. Plasma oxymorphone concentrations were determined by HPLC. Nasal absorption was rapid, nasal bioavailability was 43%, and the iv and nasal elimination profiles were similar. Oxymorphone HCI appears to have the solubility, potency, and absorption properties required for efficient nasal delivery, which is an alternative to injections.     

Computer simulation studies of biological membranes: progress, promise and pitfalls

Because of the complexity of biological membranes, computer simulations are useful adjuncts to experimental work in their study. Simulations of model membranes have provided new insights. Progress in simulating more biologically realistic membranes will require further development of statistical mechanical theory applied specifically to these systems, in conjunction with the use of powerful computers.     

The promise and pitfalls of animal and human models of relapse: Comment on Leri and Stewart (2002).

F. Leri and J. Stewart (see record 2002-06535-001) recently presented results from an animal study of lapse and relapse in an attempt to model the human situation. The authors of this comment consider two criteria for evaluating the usefulness of animal models for studies of human relapse: (a) the extent to which the animal model captures the essential components of human lapse and relapse phenomena and (b) the extent to which the conceptualization guiding the animal model is congruent with modern research and theory on animal behavior in related preparations. The authors argue that F. Leri and J. Stewart's (2002) model, as of yet, does not meet the standards suggested by these criteria. However, features of this work may prove valuable for informing efforts to develop relapse paradigms in both human and animal research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cryosurgery of the prostate: techniques and pitfalls

The preliminary data on prostate cryosurgery encompass reports only on local recurrence rates. The procedure is too new to report any survival figures. For localized organ-confined disease, the initial reports at 1 year of positive biopsies following cryosurgery range from 8% to 33%. With clinical stage C disease, a review of the literature also shows a range of 16% to 33% for local recurrence at one year. The largest series of patients treated after failure from radiation therapy is from the M.D. Anderson Cancer Center, which reports a positive biopsy rate of 29% at 6 months. Reports of major complications have included a 2% to 5% incidence of rectourethral fistulas, a 7% to 15% incidence of urinary retention requiring a secondary TURP or prolonged catheter drainage, 2% to 7% incidence of stress incontinence, and a 50% to 80% incidence of impotence. While these overall results may not be optimal to many, they do give us optimism. It is important to recognize that knowledge of the cryosurgical technique is evolving rapidly, and present modifications are not reflected yet in our results. Because hypothermia is a modality proven to cause lethal injury to cancer cells, it would be unfortunate if clinicians dismissed this modality without rigorous review of the surgical technique. The detailed methodology described in this article expedites the learning curve of practicing cryosurgeons and helps to standardize the way cryosurgery is performed.     

MR arthrography of the shoulder: variants and pitfalls

Use of magnetic resonance arthrography to evaluate pathologic conditions of the shoulder is becoming widespread. However, normal anatomy or anatomic variations can cause interpretive errors. The most common variations occur at the origins of the glenohumeral ligaments (GHLs) and the insertion of the joint capsule. Among the GHL variants, common origin of the superior and middle ligaments is the most frequent followed by thinning, thickening, or absence of a ligament, most often the middle one. Absence or thinning of one ligament is sometimes associated with thickening of another or changes in the size and shape of the anterior capsular recesses. Common normal variants of the labrum include foramen sublabrum (detachment of the anterosuperior labrum from the glenoid margin) and the Buford complex (absence of the anterosuperior labrum in association with a thick middle GHL). Pitfalls related to the arthrographic technique include (a) visualization of a deep sulcus between the insertion of the long head of the biceps tendon and the superior labrum and (b) an apparent type III capsular insertion due to overdistention of the capsule by injected contrast material.     

Primary anastomosis of the trachea: management and pitfalls

The potentiating activity of SG-86[N-(2-hydroxyethyl)nicotinamide], a denitrated metabolite of nicorandil, on the adenosine-induced vasodepression was compared with that of nicorandil in anesthetized rats. Single bolus i.v. adenosine (3-100 micrograms/kg) produced dose-dependent reductions of blood pressure, accompanied by slight decreases (except for 100 micrograms/kg) in heart rate. The adenosine-induced vasodepression was significantly enhanced during i.v. infusion of either SG-86 (100 micrograms/kg per min) as well as nicorandil (10 micrograms/kg per min). The enhancement of adenosine action by them did not occur in the presence of glibenclamide (20 mg/kg i.v.). Single bolus i.v. injections of SG-86 (0.3-30 mg/kg), except for 30 mg/kg, which caused a glibenclamide-sensitive decrease by about 5-10 mmHg in mean arterial blood pressure, had no effects on blood pressure and heart rate, whereas those of nicorandil (30-300 micrograms/kg) elicited overt reduction of blood pressure, accompanied by decreases in heart rate. The present results revealed that SG-86, like nicorandil, significantly enhanced the vasodepressor response to adenosine, probably in part through KATP channel activation, and that the activity of SG-86 was about 10 times less potent than that of nicorandil.     

Identifying illness: pitfalls and discoveries

A 63-year-old woman presented with a comatose state after a fall. Results of cranial computed tomography (CT) and magnetic resonance imaging (MRI) scans were normal. An EEG recorded 5 h after admission was very severely attenuated and slowed. Consciousness and EEG were improved the next day. No cause was detected initially. After sleep deprivation, the patient had a generalized seizure followed by a similar coma and EEG. Even a single seizure may cause a prolonged coma with a very severely attenuated and slowed EEG.     

Recognizing syncope: pitfalls and surprises

Loss of consciousness and falling are the key features of syncope. Common accompaniments include tonic and myoclonic muscle activity, eye deviations, automatisms, vocalizations and hallucinations which may render the distinction from epileptic seizures difficult. Differential diagnosis is based on the specific features and not the mere presence of these phenomena. Recognition of syncope depends also on accurate information about precipitants, premonitory symptoms and postictal events: the absence of postictal confusion has been identified as the single most powerful factor discriminating syncope from epileptic seizures whereas incontinence and head injury are common in both conditions. Investigations such as electroencephalogram, tilt testing and postictal prolactin or creatine kinase levels may be helpful but are never diagnostic in isolation. Exceptionally, hypoxic and epileptic mechanisms interact within a single attack.     

Intermetallic compounds: Their past and promise

This review serves to call attention to intermetallic compounds as a class of materials of great practical importance in both ancient and modern times and as a fascinating topic of scientific inquiry. Exploration of the relevant metallurgical history illustrates the processes by which both ideas and practical developments evolve and emphasizes that some of the threads may be traced back very far in time. Three general conclusions are drawn from the review: a) The intrinsic properties of intermetallic compounds are truly unique and at present levels of understanding are not predictable from the fundamental parameters of the constituent atoms, b) Successful applications of intermetallics do not result from the mere knowledge of their composition, crystal structure, and intrinsic properties but require as well a skillful and understanding control of their processing, c) There is desirably and necessarily a strong interplay between science and technology in the development of the intermetallic field. The technological opportunity forecast by some unique property measurements stimulates further related scientific investigation. Conversely scientific advances, both those specific to intermetallics and those pertinent to metallurgy more generally, facilitate the rate of reduction to practice of empirical discoveries. Future trends seen in the further development of intermetallics are: greater appreciation and control of subgrain structure, investigation of compounds of metastable structure, study of compounds with complex chemistry, the use of intermetallics in composites, and new insights to be drawn from data compilations such as NMR and EDS.     

Cognitive neuroscience: Origins and promise.

Both Freud and Wundt had hoped to base psychology on an understanding of the neural basis of mental events. Their efforts were unsuccessful because the structure and function of the human brain was not available for empirical study at the physiological level. Over the last part of this century, there has been amazing growth and vitality in the field of human brain function. In this paper, we trace critical developments in the fields of cognitive psychology, neuropsychology, and brain imaging related to the development of cognitive neuroscience. Cognitive neuroscience has established that the decomposition of mental events can be united with an understanding of the mental and emotional computations carried out by the human brain. Cognitive neuroscience has the capability of influencing psychology in diverse areas from how children develop to how adults age; from how humans learn to how we imagine; from volitional control to psychopathologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Paradigms and expectations: the nature of research and diagnostics

OBJECTIVES: Our purpose was to evaluate the long-term benefit of myocardial viability assessment for stratifying risk and selecting patients with low ejection fraction for coronary artery bypass grafting and to determine the relation between the severity of anginal symptoms, the amount of ischemic myocardium, and clinical outcome. METHODS: We studied 93 consecutive patients with severe coronary artery disease and low ejection fraction (median, 25%) who underwent positron emission tomography to delineate the extent of perfusion-metabolism mismatch (reflecting hibernating myocardium) for potential myocardial revascularization. Median follow-up was 4 years (range, 0 to 6.2 years). RESULTS: Fifty patients received medical therapy, and 43 patients underwent bypass grafting. In Cox survival models, heart failure class, prior myocardial infarction, and positron emission tomographic mismatch were the best predictors of survival. Patients with positron emission tomographic mismatch receiving bypass grafting had improved 4-year survival compared with those on medical therapy (75% versus 30%; P =.007) and a significant improvement in angina and heart failure symptoms. In patients without positron emission tomographic mismatch, bypass grafting tended to improve survival and symptoms only in those patients with severe angina (100% versus 60%; P =.085), whereas no survival advantage was apparent in patients with minimal or no anginal symptoms (63% versus 52%; P =.462). CONCLUSIONS: Patients with low ejection fraction and evidence of viable myocardium by positron emission tomography have improved survival and symptoms with coronary bypass grafting compared with medical therapy. In patients without evidence of viability, survival and symptom improvement with bypass grafting are apparent only among those patients with severe angina.     

Childhood lead poisoning: the promise and abandonment of primary prevention

In 1991, the Public Health Service published the Strategic Plan for the Elimination of Childhood Lead Poisoning. This document marked a fundamental shift in federal policy from finding and treating lead-poisoned children to authentic primary prevention. It spelled out a 15-year strategy to achieve this goal and provided a cost-benefit analysis showing that the monetized benefits far exceeded the costs of abatement. A strong national effort to eliminate the disease developed. Now, 7 years after publication of the plan, primary prevention of lead exposure has been abandoned. This article examines the role of some prevailing attitudes and institutions in derailing the effort. Some institutions--the lead industry, real estate interests, and insurance interests--behaved as anticipated. Others, including private pediatricians, the American Academy of Pediatrics, some federal agencies, and a public interest group ostensibly dedicated to eliminating lead poisoning, also played an unexpected part in derailing the plan.     

Economic glossary: pitfalls of interpretation

Sharp discrepancy exists between the concepts declared and the measures introduced with urgency by the government and the real praxis of the health-care institutions, which are delivered to and suffer from the heaviest financial-economical restrictions. The situation may partly be attributed to the missing system-specific interpretation of some leading categories. Attempts were made to point at some harmful consequences of this failure and to reinterpret basic categories, so as to contribute to a better agreement of the participants in favour of our patients' welfare.     

Perimenopause: limits and pitfalls of colposcopic evaluation

A new surgical instrument is presented that is designed for manual placement of Kirschner wires. Its construction is based on that of a micro-screwdriver. The whole instrument is cannulated for wires of any length up to a gauge of 1.2 mm. This instrument facilitates smooth placement of Kirschner wires in difficult situations, especially in hand surgery.     

MR arthrography of the elbow: normal anatomy and diagnostic pitfalls

PURPOSE: Our goal was to determine the normal MR arthrographic appearance of the elbow and to identify the potential diagnostic pitfalls of this technique. METHOD: MRI with intra-articularly administered gadopentetate dimeglumine was performed in seven elbow joints derived from cadavers. Coronal, sagittal, and axial SE T1-weighted images with fat suppression and coronal 3D SPGR images with fat suppression were obtained in each elbow. The elbows were then sectioned. RESULTS: This technique allowed depiction of the cartilaginous surfaces of the elbow joint as well as clear delineation of the inner surface of the collateral ligaments. Potential diagnostic pitfalls included fat pads projecting into the joint, synovial folds, and cartilaginous pseudoerosions. CONCLUSION: MR arthrography allows clear delineation of the intraarticular structures of the elbow. However, diagnostic pitfalls exist that increase the difficulty of interpreting MR arthrographic images.     

Cross-lagged panel correlation: Practice and promise.

Considers various problems in cross-lagged correlation analysis. Serious questions are raised concerning the plausibility of the stationarity assumption during periods of rapid developmental growth. A set of practical guidelines is detailed for reporting the results of the analysis, and a new method of estimating communality ratios is outlined. The issue of causal predominance is viewed within the context of alternative models. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Standards and quality control: problems and pitfalls

The proliferation of standards and quality assurance programs is posing a major problem for mental health administrators. The authors review some of these problems and emphasize the differences between cost and quality controls. They propose that quality controls be judged on their ability to improve patient care and suggest that administrators consider the establishment of quality control offices.