The suppression of star formation by powerful active galactic nuclei.

The old, red stars that constitute the bulges of galaxies, and the massive black holes at their centres, are the relics of a period in cosmic history when galaxies formed stars at remarkable rates and active galactic nuclei (AGN) shone brightly as a result of accretion onto black holes. It is widely suspected, but unproved, that the tight correlation between the mass of the black hole and the mass of the stellar bulge results from the AGN quenching the surrounding star formation as it approaches its peak luminosity. X-rays trace emission from AGN unambiguously, whereas powerful star-forming galaxies are usually dust-obscured and are brightest at infrared and submillimetre wavelengths. Here we report submillimetre and X-ray observations that show that rapid star formation was common in the host galaxies of AGN when the Universe was 2-6 billion years old, but that the most vigorous star formation is not observed around black holes above an X-ray luminosity of 10(44) ergs per second. This suppression of star formation in the host galaxy of a powerful AGN is a key prediction of models in which the AGN drives an outflow, expelling the interstellar medium of its host and transforming the galaxy's properties in a brief period of cosmic time.

Submillimetre galaxies reside in dark matter haloes with masses greater than 3 × 10(11) solar masses.

The extragalactic background light at far-infrared wavelengths comes from optically faint, dusty, star-forming galaxies in the Universe with star formation rates of a few hundred solar masses per year. These faint, submillimetre galaxies are challenging to study individually because of the relatively poor spatial resolution of far-infrared telescopes. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations. A previous attempt at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model. Here we report excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350 and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter haloes with a minimum mass, M(min), such that log(10)[M(min)/M(⊙)] = 11.5(+0.7)(-0.2) at 350 µm, where M(⊙) is the solar mass. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the Universe, and is lower than that predicted by semi-analytical models for galaxy formation.

Echocardiographic diagnosis of intraventricular clot.

The literature contains many reports of the echocardiographic findings in left atrial myxoma and clot; however, descriptions of left ventricular thrombus or tumor are rare. We discuss here the echocardiographic findings in a patient with a large apical left ventricular thrombus which was confirmed both angiographically and pathologically. The importance of echocardiographically examining the area below the mitral valve near the apex of the left ventricle, where most of the thrombi are located, is stressed.

Persistence of biologic activity after disappearance of propranolol from the serum.

In order to evaluate the duration of the biologic effects of propranolol after the drug was discontinued, we evaluated a variety of noninvasively determined hemodynamic parameters. Significant depression was found in the heart rate (18 per cent), cardiac output (13 per cent) (determined echocardiographically), and the triple product of blood pressure, heart rate, and systolic ejection time (16 per per cent) during administration or propranolol (200 mg. per day) to 9 normal volunteers. Significant depression of these parameters was present 12 hours after discontinuing the drug. By 12 hours, serum propranolol levels had returned 90 per cent toward their base line; however, at the same time, the heart rate and cardiac output had returned only 19.4 and 14.3 per cent toward their base-line values, and the triple product had returned 41 per cent toward its baseline. By 36 hours no biologic effect was seen. Thus if propranolol were discontinued 2 days prior to cardiac surgery, no significant biologic effect would remain to complicate the patient's postoperative course.

The changing status of ejection fraction as a predictor of early mortality following surgery for acquired heart disease.

Several reports in the literature and our experience prior to 1974 support the thesis that operative risk in patients with acquired heart disease and poor ventricular function (as assessed by a biplane ejection fraction [EF] less than or equal to 0.40) was very significantly increased over the risk in patients with normal ventricular function. These results led to disagreement in the literature regarding the advisability of surgery in patients with poor ventricular function. Various EFs from less than 0.31 to less than 0.50 were suggested as contradicting elective surgery, while more aggressive groups recommended surgery in all patients with angina. Precise comparison of the results reported by different groups was not always possible because of the common reliance on single-plane right anterior oblique ventriculograms, which tend to underestimate EF and overestimate operative risk. Using biplane ventribulograms for accurate estimation of EF, we have demonstrated a significant reduction in 30-day operative risk to a clinically acceptable 3 percent (1/32) for single valve replacement and aortocoronary surgery patients with poor ventricular function (EF less than or equal to 0.40) during 1974. Considering the high risk of medically treated patients with reduced ventricular function, these results support further evaluation of surgical palliation for patients with valvular or coronary heart disease and reduced ventricular function.

Decreased perceptual sensitivity to emotion-evoking stimuli in depression.

We measured two aspects of emotional response in depressed patients, as a preliminary study of the potential usefulness of such measures for elucidating pathophysiological mechanisms. First we used electromyography to measure the automatic mimicry on an individual's own face of facial displays of emotion observed on the faces of others. Next we used the fused dichotic listening paradigm to measure selective perception of both positive and negative emotion-related words as opposed to neutral words. Patients failed to show the normal facial mimicry of both positive and negative facial displays, despite normal cognitive processing of the stimuli. They also heard significantly fewer positive and negative words on the dichotic tests than did healthy controls. This suggests that depressed patients are hyposensitive to emotion-related stimuli in general.

Superego defense analysis in the termination phase.

This paper is a contribution to recent efforts to identify areas in clinical theory and practice in which the analyst's authority is used, rather than analyzed, to achieve therapeutic results. In the termination phase there may occur an intensification of transferences of authority (superego transferences) in response to the aggression inherent in termination. Analysts may develop counterresistances to analyzing these defense transferences, since their analysis exposes the analyst to the patient's heightened aggression at termination. The literature on termination may have contributed to analysts' falling short in analyzing these transferences, by its having accorded internalizing mechanisms a prominence in the therapeutic action of termination that they otherwise lack in contemporary ego psychological theories of therapeutic action. Gray's formulation of the superego as an analyzable defensive activity is applied to events in the termination period, thereby bringing into focus conflicts over aggressive impulses defended against by superego forces. Clinical vignettes from the termination phase of an analysis are presented.

Effect of morphine on splanchnic blood flow.

Splanchnic blood flow was measured by the constant infusion of indocyanine green given before and after morphine 0.2 mg/kg (maximum 15 mg) intravenously in 13 patients. Splanchnic blood flow increased from 1012 +/- 98 ml/min to 1200 +/- 118 ml/min after the administration of morphine, a 19 per cent increase (P less than 0.025). Splanchnic vascular resistance decreased from 0.094 +/- 0.010 to 0.081 +/- 0.010 mmHg min/ml, a 16 per cent decrease (P less than 0.001). There was no significant change between baseline and post-morphine values in systemic arterial pressure (92.2 +/- 3.8 and 89.0 +/- 2.9 mmHg), hepatic vein wedge pressure (7.1 +/- 1.0 and 7.8 +/- 0.6 mmHg), or right atrial mean pressure (4.5 +/- 0.6 and 4.3 +/- 0.7 mmHg). This study shows that morphine induced significant splanchnic arteriolar dilatation.

Intraoperative myocardial ischemia: localization by continuous 12-lead electrocardiography.

Based primarily on results obtained during exercise treadmill testing, electrocardiographic (ECG) leads II and V5 are the suggested optimal leads for detecting intraoperative myocardial ischemia. However, these recommendations have not been validated in this setting using all 12 ECG leads. Accordingly, the authors studied 105 patients with known or suspected coronary artery disease (CAD) undergoing noncardiac surgery with general anesthesia by continuously recording the 12-lead ECG intraoperatively in all patients. The average duration of monitoring was 8.2 +/- 2.7 h (mean +/- SD). Ischemic episodes (i.e., greater than or equal to 1-mm horizontal or downsloping ST depression, greater than or equal to 1.5-mm slowly upsloping ST depression or greater than or equal to 1.5-mm ST elevation in a non-Q wave lead) occurred in 25 patients (24%). Out of 51 ischemic episodes, 45 involved ST depression alone, and the remaining six involved both ST depression and elevation. ST segment changes occurred in a single lead only in 14 episodes, while multiple leads were involved in 37 episodes. Lead sensitivity was estimated assuming that all ST segment changes were true positive responses. Sensitivity using a single lead was greatest in V5 (75%) and V4 (61%), and intermediate in II, V3, and V6 (33%, 24%, and 37%, respectively). The remaining seven leads demonstrated very low sensitivity (2-14%) or exhibited no ischemic changes (I and a VL). Combining leads V4 and V5 increased sensitivity to 90%, while the standard clinical combination, II and V5, was only 80% sensitive. Sensitivity increased to 96% by combining II, V4, and V5. The further addition of V2 and V3 (five leads) increased sensitivity to 100%. This study confirms previous recommendations for the routine use of a V5 lead (either uni- or bipolar) in all patients at risk for ischemia. V4 is more sensitive than lead II, and should be considered as a second choice. However, lead II, superior for detection of atrial dysrhythmias, is more easily obtained with conventional monitors. The use of all three would appear to be the optimal arrangement for most clinical needs, and is recommended if the clinician has the capability.