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This paper presents results from an empirical study of four key psychodynamic concepts (self-directed aggression, object loss, ego functioning disturbance, pathological object relations) of suicidal behavior. The sample consists of hospitalized psychiatric patients following a suicide attempt (attempters: n = 52) and demographically similar hospitalized psychiatric patients with no history of suicidal behavior (controls: n = 47). The study was designed to ascertain whether attempters differed from matched psychiatric control patients on the four psychodynamic constructs hypothesized to be associated with suicide. It was predicted that attempters would manifest higher levels of depression and self-targeted anger, a more significant history of loss, less adaptive defenses, and more primitive object representations. Results strongly supported an object-relational view of suicidal behavior. In addition, support for the loss hypothesis was found in the identification of one specific constellation of losses. Namely, attempters were significantly more likely to report a history of childhood loss combined with a recent loss in adulthood than were their nonattempter counterparts. Limited support was provided for the other two hypotheses in differentiating suicidal from nonsuicidal severely ill psychiatric patients. This unexpected finding is examined and suggestions are made for the refinement and greater specification of psychodynamic theories regarding the etiology of suicidal behavior, with the aim of differentiating individuals prone to such action from those with similar psychopathology and dynamic issues who do not actually attempt suicide. Limitations of the study are discussed and implications of the findings for the theory and treatment of suicidal behavior are offered.

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BACKGROUND: Current literature documents use of the radial artery (RA) for myocardial revascularization only as an alternative conduit in cases where the saphenous veins have been previously harvested or are unsuitable for use. Large-scale routine clinical use of the RA as the conduit of choice has not been reported. METHODS: This prospective study evaluated the harvest of the RA from 933 patients and the subsequent use of the conduit as a preferred coronary artery bypass graft second only to the left internal thoracic artery in 930 of these patients. RESULTS: Unilateral RA harvest was performed in 786 patients and 147 patients had bilateral RA harvest. A total of 1080 RAs were harvested; 214 (19.8%) originated from the dominant forearm. There was a mean of 3.30+/-0.93 grafts per patient of which 2.43+/-0.83 were arterial grafts. The mean number of RA grafts was 1.43+/-0.53. Operative mortality was 2.3% with none due to the RA graft(s). There was no ischemia nor motor dysfunction in the operated hands. Thirty-two (3.4%) patients experienced transient thenar dysesthesia that resolved in 1 day to 6 weeks. CONCLUSIONS: Our results demonstrate that routine total or near total arterial myocardial revascularization may be achieved safely and effectively with the use of one or both RAs in conjunction with the internal thoracic artery.

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Advances in the management of acute myocardial infarction can significantly improve outcome, primarily through highly time-dependent coronary reperfusion and successfully resolving early complications. Effectiveness of treatment is now more limited by delays in reperfusion and number of patients who receive coronary reperfusion than available therapy. Specific methods of decreasing the time to reperfusion and increasing the number of patients treated must be broadly applied to further reduce morbidity and mortality. Facilities that manage myocardial infarction should be classified according to capabilities to promote emergency transport to the nearest facility offering definitive care, generally, thrombolysis or urgent PTCA. Standardized evaluation and treatment protocols are critical in providing rapid and optimum care. Essential protocols include questionnaires for thrombolysis candidacy and diagnosis triage; critical initial management pathways; patient management algorithms; and standardized orders for thrombolysis, anticoagulation, and initial coronary care admission.

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We compared staffing patterns in primary care specialties in three large health maintenance organizations (HMOs) with the national requirements for physicians in 1990 projected by the Graduate Medical Education National Advisory Committee (GMENAC). The HMOs varied in their use of nonphysician providers, family practice specialists, and subspecialists in internal medicine. Nevertheless, projections based on the average experience of these HMOs suggest that 20 percent fewer primary care physicians for children and 50 percent fewer primary care physicians for adults will be needed to meet national primary care needs in 1990 than projected by the GMENAC. As enrollment in HMOs continues to grow, their impact on national requirements for medical personnel will increase. The variety of staffing patterns found among HMOs operating in highly competitive markets suggests the importance of considering alternative configurations for meeting national requirements for primary care.

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Fertile eggs of the Coturnix quail were exposed twice a day for 30 min to 2.45-GHz continuous wave radiation at power densities of 25 or 50 mW cm-2 throughout the 17-day incubation period. Other eggs were exposed to 20 degrees C or 24 degrees C temperatures twice daily. Repeated exposures to 20 degrees C, 24 degrees C, or 25 mW cm-2 did not reduce hatchability. Irradiation at 50 mW cm-2 lowered hatchability, probably as a result of high egg temperatures. Hatchlings that had been irradiated by microwaves as embryos had normal growth rates and no obvious developmental abnormalities.

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In a group of 40 patients discharged from the hospital after mitral valve replacement with an Ionescu-Shiley pericardial xenograft from January, 1977, to December, 1980, seven instances of valve failure occurred. This unprecedented incidence of bioprosthetic dysfunction after mitral valve replacement with the Ionescu-Shiley pericardial xenograft led us to update the follow-up of our patients receiving this valve in the mitral position. The results of our survey showed, at 6 years postoperatively, an actuarial survival rate of 72%, an actuarial probability of being free from emboli of 62%, and an actuarial freedom from prosthetic failure of 60%. The explanted valves showed complete absence of the neoendothelial lining of the Dacron-covered frame and lesions resembling those observed in Ionescu-Shiley pericardial xenografts removed from our fatigue test system after a mean of 29 +/- 17 X 10(6) cycles. This similarity prompted a classification of tears occurring in the mitral Ionescu-Shiley pericardial xenograft, which is of extreme importance, since the clinical presentation and outcome of patients with a failing valve differs according to the type of rupture. The lesions of the cusp observed in clinical specimens were possibly related to the continuous trauma of the tissue against the bare Dacron cloth during closure of the valve. It is concluded that (1) actual durability and thrombogenicity of the Ionescu-Shiley pericardial xenograft in the mitral position needs to be carefully reassessed, (2) close follow-up of such patients by clinical and two-dimensional echocardiographic evaluation is advisable after the third postoperative year, and (3) failure of the mitral Ionescu-Shiley pericardial xenograft may occur suddenly, and awareness of this complication is the clue to prompt recognition and treatment of such patients.

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Aversion/attraction experiments were conducted to determine whether birds can perceive the presence of 2.45 GHz continuous wave microwave irradiation by observing whether Blue Jays (Cyanocitta cristata) exhibit an attraction or an aversion to the field when exposed to 25 and 50 mW/cm2. At power densities of 25 and 50 mW/cm2 Blue Jays exhibit an aversion to microwave irradiation.

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The haemodynamic characteristics and durability of mitral bioprostheses were evaluated and compared in vitro in a pulse duplicator and in a fatigue test system. Porcine xenografts were shown to be the most stenotic of all bioprostheses, studied at rates simulating both rest and exercise; on the other hand the new generation of biological valves showed a clear improvement in haemodynamics compared with the standard porcine and pericardial prostheses so far used clinically. Durability tests performed at a rate of 1600 to 1800 beats per minute and with a closing pressure ranging from 80 to 100 mmHg showed that the Ionescu-Shiley and Edwards pericardial xenografts last significantly longer than the Hancock and Carpentier Edwards porcine valves and Hancock pericardial bioprosthesis. Correlation between the mode of failure of pericardial and porcine valves in vitro and in vivo clearly demonstrates that a major role in valve failure is played by mechanical stress. This can be either a consequence of the continuous trauma sustained by the tissue hitting against the bare dacron cloth of the sewing ring during the movements of the cusps. or a result of fatigue occurring and the bending points of the leaflets. The results of this study underline the importance of a continued in vitro evaluation of both haemodynamics and durability of bioprostheses, since some of the pericardial valves which had the best haemodynamic performance showed the worst resistance to fatigue-induced failure. A careful selection of the tissue, modification of the stent design and avoidance of a dacron covered frame are suggested to improve long-term durability of biological prostheses.

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To obtain a valve with better hemodynamic performance and longer durability than the currently available bioprostheses, a single-cusp pericardial xenograft has been developed. This valve has been tested extensively both in vitro, in a pulse duplicator and in a fatigue-testing system, and in vivo, in a series of dogs and sheep. Hemodynamic studies showed improved hemodynamic performance compared with other biological and mechanical valves. Effective orifice areas were larger and performance indexes higher, especially in the small sizes. Accelerated fatigue testing showed durability significantly superior to that of other biological devices. Animal experiments have established that the single cusp remains pliable even after more than two years of insertion. There is a low incidence of calcification and good preservation of the collagen matrix. This preliminary experience demonstrates that the unicusp pericardial xenograft has superior hemodynamics, increased resistance to fatigue-induced lesions, and a low incidence of calcification. These results might indicate an extended in vivo durability for this device.

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Four patients had signs of primary bioprosthetic dysfunction within the fourth postoperative year after mitral valve replacement with an Ionescu-Shiley pericardial xenograft; they represent approximately 9% of patients with Ionescu-Shiley pericardial xenograft mitral valves followed up for more than 3 years at our institution. Pathological investigation showed severe incompetence of all explanted valves due to cusp tears and lacerations. Histologic study of the pericardial tissue disclosed mild to moderate collagen degeneration, without infection or calcification. Neoendothelial formation on the Dacron cloth of the sewing ring was either absent or minimal. The high incidence of valvular incompetence prompted us to try to establish a correlation between the in vivo and in vitro modes of failure of the Ionescu-Shiley pericardial xenograft. For this purpose, 10 unimplanted Ionescu-Shiley pericardial xenograft valves were tested in a fatigue test system. Severe fatigue-induced lesions occurred in this group after an average of 29.09 +/- 17.26 X 10(6) cycles; initial failure could be recognized in six of them after an average of 16.94 +/- 20.12 X 10(6) cycles. Valves tested in the fatigue test system showed tears and lacerations similar to those noted in the Ionescu-Shiley pericardial xenografts obtained from the four patients (which were assumed to have functioned for more than 100 X 10(6) cycles in each case). Correlation between results of the fatigue testing and our clinical experience enabled us to recognize four types of tears which may occur in the Ionescu-Shiley pericardial xenograft. The results of this investigation showed the following: (1) Primary tissue failure of the Ionescu-Shiley pericardial xenograft may occur suddenly. (2) A classification of tears occurring in Ionescu-Shiley pericardial xenograft valves is useful since the clinical presentation of patients may differ according to type and location of the lesion. (3) In the manufacture of pericardial valves, particular care must be observed in selection of the tissue and in the frame design. (4) Improvement of the quality control is one of the clues to enhance durability of the Ionescu-Shiley pericardial xenograft.

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Seventeen birds from 12 flocks were exposed to microwave radiation under various combinations of power density and duration; three birds from two additional flocks served as sham-exposed controls. Experiments were conducted outdoors at Manomet, Massachusetts (41 degrees 56'N, 70 degrees 35'W) under normal winter ambient temperatures. Although irradiated birds maintained their positions within a flock hierarchy with one exception, some appeared to have a change in their level of aggression after exposure.

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This report presents the results of an evaluation of a prenatal health education program conducted within a health maintenance organization (HMO) setting. Specifically, the behavioral, birth, and treatment-cost outcomes for 57 women in an experimental group who received individual nutrition counseling and a home-correspondence smoking cessation program were evaluated against the outcomes for 72 women in a control group who received standard prenatal care. In comparison with the controls, a greater percentage of women in the experimental group quit smoking during pregnancy (49.1 percent versus 37.5 percent). Of those who smoked throughout their pregnancy, women in the experimental group had a greater reduction in their mean rate of daily smoking. A significantly greater percentage of experimental group women adjusted their diets during the prenatal period (91 percent versus 68 percent), and particular success was achieved in increased consumption of dairy products and vegetables, decreased consumption of coffee, and adequate weight gain during pregnancy. Analysis of birth outcome data revealed that infants born to the experimental group had a significantly higher mean birth weight than infants born to the controls (121.34 oz versus 113.64 oz). The experimental group also had fewer low birth weight infants (7.0 percent versus 9.7 percent for controls). Hospital treatment cost savings associated with the reduced incidence of low birth weight infants among experimental group women yielded an overall benefit-cost ratio for the prenatal program of approximately 2:1.

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These studies have indicated some quantitative aspects of the kallikrein kinin system in sepsis. While other investigators have noted the fall in plasma kininogen in patients with sepsis, e.g. Erdos and colleagues (23), this study has indicated that it is the fall in the LMWK that is significant in these patients. LMWK comprises of three-quarters of the total plasma kininogen and its consumption can lead to the production of 2.24 million picograms bradykinin/ml plasma. In health bradykinin concentration is of the order of 100-400 picograms/ml. It is not unreasonable to suggest therefore, that bradykinin levels are increased in acute disease and other investigators have shown this by direct assay of the peptide in such patients. The present study has shown that once bradykinin is generated in the circulation in terms of ng/ml, even with passage through the lung, systemic effects occur, namely reduction in TPR and a fall in CO and BP. Thus, bradykinin could be the humoral factor responsible for the hyperdynamic state and systemic hypotension in severe sepsis. It is apparent that metabolism of bradykinin involves more than simply clearance of the peptide. It appears that bradykinin can stimulate the production of other vasoactive mediators by the lung. The consumption of LMWK in sepsis indicates that it is not plasma kallikrein activity but rather non-specific kininogenase activity that is critical. This may be important not only from the viewpoint of kinin generation, but also because of the consumption of plasma protease inhibitors. A mechanism to control or inhibit such protease activity offers a possible therapeutic approach to circulatory failure in these patients.

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