Comprehensive Test of the Brink-Axel Hypothesis in the Energy Region of the Pygmy Dipole Resonance.

The validity of the Brink-Axel hypothesis, which is especially important for numerous astrophysical calculations, is addressed for ^{116,120,124}Sn below the neutron separation energy by means of three independent experimental methods. The γ-ray strength functions (GSFs) extracted from primary γ-decay spectra following charged-particle reactions with the Oslo method and with the shape method demonstrate excellent agreement with those deduced from forward-angle inelastic proton scattering at relativistic beam energies. In addition, the GSFs are shown to be independent of excitation energies and spins of the initial and final states. The results provide a critical test of the generalized Brink-Axel hypothesis in heavy nuclei, demonstrating its applicability in the energy region of the pygmy dipole resonance.

Radiative Width of the Hoyle State from γ-Ray Spectroscopy.

The cascading 3.21 and 4.44 MeV electric quadrupole transitions have been observed from the Hoyle state at 7.65 MeV excitation energy in ^{12}C, excited by the ^{12}C(p,p^{'}) reaction at 10.7 MeV proton energy. From the proton-γ-γ triple coincidence data, a value of Γ_{rad}/Γ=6.2(6)×10^{-4} was obtained for the radiative branching ratio. Using our results, together with Γ_{π}^{E0}/Γ from Eriksen et al. [Phys. Rev. C 102, 024320 (2020)PRVCAN2469-998510.1103/PhysRevC.102.024320] and the currently adopted Γ_{π}(E0) values, the radiative width of the Hoyle state is determined as Γ_{rad}=5.1(6)×10^{-3} eV. This value is about 34% higher than the currently adopted value and will impact models of stellar evolution and nucleosynthesis.

Doppler echocardiographic evaluation of Hancock and Björk-Shiley prosthetic values.

Doppler echocardiographic characteristics of normally functioning Hancock and Björk-Shiley prostheses in the mitral and aortic positions were studied in 50 patients whose valvular function was considered normal by clinical evaluation. Doppler studies were also performed in 46 patients with suspected malfunction of Hancock and Björk-Shiley valves and who subsequently underwent cardiac catheterization. Mean gradients were estimated for both mitral and aortic valve prostheses and valve area was calculated for the mitral prostheses. Doppler prosthetic mitral valve gradient and valve area showed good correlation with values obtained with cardiac catheterization (r = 0.93 and 0.97, respectively) for both types of prosthetic valves. The correlation coefficient (r = 0.93) for mean prosthetic aortic valve gradient was also good, although Doppler echocardiography overestimated the mean gradient at lower degrees of obstruction. Regurgitation of Hancock and Björk-Shiley prostheses in the mitral and aortic positions was correctly diagnosed. These results suggest that Doppler echocardiography is a reliable method for the characterization of normal and abnormal prosthetic valve function.

The role of the MDR-1/P-170 mechanism in the development of multidrug resistance in chronic myeloid leukemia.

We studied blood and bone marrow cells from 42 patients with Ph-chromosome positive chronic myeloid leukemia (CML) and 20 normal subjects for amplification of the multidrug resistance gene (MDR-1) by Southern blotting and for overexpression of P-glycoprotein (P-170) by immunocytochemistry on intact cells with the monoclonal antibody C219. No P-170 could be detected in normal bone marrow or buffy coat. Overexpression of P-170 without amplification of MDR-1 was found in four of 11 patients with chronic phase CML at diagnosis, seven of 16 patients treated with busulfan or hydroxyurea in chronic phase and four of 15 patients in blast crisis. The P-170 overexpression involved only cells of the granulocyte lineage and varied from weak to strong in individual patients. It did not correlate with duration of or response to treatment during chronic phase. In transformation P-170 expression was seen in differentiated cells of the granulocyte lineage but not in blast cells, although three patients had been treated intensively with lipophilic and other cytotoxic drugs to which they had become resistant. We conclude that resistance to busulfan and hydroxyurea in chronic phase and resistance of blast cells to other cytotoxic drugs in transformation are not mediated primarily through the MDR-1/P-170 pathway.

Electrocardiographic criteria for diagnosis of left ventricular hypertrophy in the presence of complete right bundle branch block.

The usual electrocardiographic criteria recommended for left ventricular (LV) hypertrophy may be unreliable in the presence of complete right bundle branch block (BBB). Thirty-six standard electrocardiographic criteria for LV hypertrophy were evaluated in 100 patients (mean age +/- standard deviation 67 +/- 11 years) with right BBB and technically satisfactory echocardiograms. Eight additional electrocardiographic criteria derived from this study also were evaluated. LV mass index was determined from the echocardiogram using the Penn method. LV hypertrophy defined as LV mass index greater than 132 g/m2 in men and 109 g/m2 in women was present in 56 of the 100 patients. Electrocardiographic criteria with the highest sensitivity were SIII + (R + S) maximal precordial lead greater than or equal to 30 mm (sensitivity 68%), specificity 66%), left axis deviation of -30 degrees to -90 degrees (sensitivity 59%, specificity 71%) and combination of left axis deviation and SIII + (R + S) maximal precordial lead greater than or equal to 30 mm (sensitivity 52%, specificity 84%). The electrocardiographic criteria with the highest sensitivity and specificity greater than 90% were left axis deviation of -30 degrees to -90 degrees and SV1 greater than 2 mm (sensitivity 34%), point-score system, RaVL greater than 12 mm and RI + SIII greater than 25 mm (each with a sensitivity of 27%). In general, limb lead voltage criteria such as RaVL greater than 11 mm (sensitivity 29%, specificity 86%) had higher sensitivities than criteria using right precordial lead S-wave voltage criteria such as SV1 + RV5, V6 greater than 35 mm (sensitivity 2%, specificity 100%).(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic profile of the transplanted human heart in clinically well recipients.

Thirty-four clinically well heart transplant recipients, aged 21 to 60 years, were selected for echocardiographic study at 12 +/- 2 months after transplantation. All had normal findings at stress thallium scintigraphy and at radionuclide left ventriculography, and no endomyocardial biopsy evidence of rejection was found within 36 hours of study. Multiple echocardiographic measurements were compared with those from two control groups. The first control group consisted of 15 normal subjects of similar ages as the donors, and the second group consisted of 15 normal subjects of similar ages as the recipients. Left ventricular mass (193 +/- 55 gm) was significantly increased in the transplant recipients compared with both control groups (p less than 0.001). Left ventricular volumes and ejection fractions of the transplanted heart, however, were normal. Right ventricular diastolic wall thickness (0.6 +/- 0.1 cm) and chamber area in both diastole (23.3 +/- 3 cm2) and systole (15.7 +/- 4 cm2) were significantly increased in the transplant patients (p less than 0.001), but fractional area change was similar to that of the normal group. Both left atrial area (26.9 +/- 4 cm2) and right atrial area (20.7 +/- 4 cm2) were significantly increased in the transplant recipients (p less than 0.001). One year after transplantation, clinically well recipients are characterized by increased left ventricular mass, but normal volumes and ejection fraction, increased right ventricular wall thickness and cavity size, but normal right ventricular systolic function, and markedly dilated atria.

Sequential positron emission tomographic evaluations of brain metabolism in acute herpes encephalitis.

This first known positron emission tomography report on metabolic changes in acute herpes simplex virus (HSV-1) encephalitis demonstrates focal hypermetabolism in areas of cerebral cortex adjacent to actively inflamed hippocampus acutely infected with HSV-1. When neuropsychiatric symptoms recurred in a previously healthy 61-year-old patient 1 month after recovering from acute HSV-1 encephalitis, repeat positron emission tomography with fluorodeoxyglucose was helpful in ruling out recurrent active infection by showing marked hypometabolism throughout the previously infected temporal lobe.

Impairment of left atrial appendage function after spontaneous conversion of atrial flutter.

This paper reports a patient in atrial flutter who spontaneously converted to sinus rhythm while undergoing a transesophageal echocardiogram. Atrial appendage flow velocities were noted to be significantly decreased after conversion to sinus rhythm. Spontaneous contrast also developed in the left atrium shortly after conversion. Spontaneous cardioversion may be associated with decreased mechanical activity of the left atrium and appendage, resulting in "stunning." This provides a possible explanation for the occurrence of thromboembolic events in patients without apparent thrombus before cardioversion.

Comparison of atrial contribution to cardiac hemodynamics in patients with normal and severely compromised cardiac function.

The importance of atrial contribution to cardiac function in patients with congestive heart failure is controversial. Ten patients with severe congestive failure (Group A) and 10 patients with normal ventricular function (Group B) were studied during atrial and ventricular pacing. Left ventricular ejection fraction, baseline pulmonary capillary wedge pressure, and baseline cardiac index were different between Group A and Group B patients: 22 +/- 10 vs. 65 +/- 11 (p less than 0.01); 21 +/- 5 vs. 8 +/- 4, (p less than 0.01); and 2.8 +/- 0.5 vs. 3.5 +/- 1.0 (p = 0.05). Compared with atrial pacing, cardiac index decreased from 2.8 +/- 0.6 to 2.2 +/- 0.5 (p less than 0.01) in Group A and from 3.6 +/- 0.7 to 2.9 +/- 0.5 (p less than 0.01) in Group B, during ventricular pacing. Pulmonary capillary wedge pressure increased by similar amounts in both groups during ventricular pacing. The change in cardiac index, % change in cardiac index, and change in pulmonary capillary wedge pressure from atrial to ventricular pacing, were not different between Group A and Group B patients. By logistic regression analysis, no association was found between the % change in cardiac index and the following variables: left ventricular ejection fraction, left ventricular end-diastolic volume, baseline pulmonary capillary wedge pressure, change in pulmonary capillary wedge pressure, and baseline cardiac index. The atrial contribution to resting steady-state cardiac function is similar between patients with severe congestive failure and those with preserved ventricular function.

Echocardiographic evaluation of patients with a left ventricular device.

Limited donor heart availability is primarily responsible for the renewal of interest in mechanical left ventricular assist devices (LVADs) as a bridge to transplantation. Donor availability is unlikely to increase significantly in the near future. Experience to date has shown that many patients can be maintained long enough to undergo transplantation, and LVADs may be acceptable as alternate therapy in some who may not be candidates for transplantation. However, criteria for noninvasive evaluation of patients on LVADs have not been developed. In a prospective study using serial echocardiography, we found that aortic valve opening, aortic forward flow, nonlaminar flow in the left ventricle, and mismatch of Doppler derived cardiac output at the pulmonic valve and device output are associated with device malfunction. Echocardiography was diagnostic in five of six patients with clinical instability unrelated to the device. These findings suggest that echocardiography is helpful in the routine evaluation of patients on LVADs.

Neuronal intranuclear hyaline inclusion disease associated with premature coronary atherosclerosis.

Neuronal intranuclear hyaline inclusion disease (NIHID) has been recognized in 14 patients. It usually occurs in the first and second decades but has been seen in the sixth. Both sexes are affected by this sporadic multisystem degenerative disorder that has involved the central and peripheral nervous systems with fibrillar and granular intranuclear inclusions. NIHID appears to be several variants of a multisystem degenerative disease as illustrated by the combination of a spontaneous, degenerative central and peripheral nervous system disorder with neuronal intranuclear inclusions and severe atherosclerotic coronary artery disease in a 23-year-old white man. Beginning at 11 years of age, this patient had experienced diffuse muscle spasms, dysarthria, dysphagia, tremors, ataxia, oculogyric crises, progressive muscle weakness, and atrophy. At autopsy, neuronal intranuclear hyaline inclusions and neuronal loss were seen in his brain, brainstem, cerebellum, spinal cord, bowel, bladder, and esophagus. These fibrillary and granular Cowdry type A and B intraneuronal inclusions were consistent with the diagnosis of NIHID associated with severe coronary atherosclerosis.

Aortic regurgitation. Detection of left ventricular dysfunction by exercise echocardiography.

Left ventricular performance was assessed in 20 symptom free patients and 10 with symptoms, all with isolated aortic regurgitation, by measuring the echocardiographic peak velocity of circumferential fibre shortening (echo peak Vcf) at rest and during graded bicycle ergometer exercise in the supine position. The normal left ventricular response during such exercise was first determined in 20 healthy controls. On the basis of their resting and exercise echo peak Vcf, the 30 patients with aortic regurgitation could be separated into three groups: Group 1 comprised 11 symptom free patients with a normal resting echo peak Vcf which increased normally with exercise; group 2 comprised nine symptom free patients with a normal resting echo peak Vcf but with a subnormal response to exercise; group 3 consisted of 10 patients with symptoms with a depressed resting echo peak Vcf which remained subnormal with exercise. Subsequent cardiac catheterisation disclosed normal ejection fractions in patients in group 1, borderline ejection fractions in those in group 2, and reduced ejection fractions in those in group 3. Echocardiographic assessment of left ventricular performance during supine isotonic exercise may provide a simple noninvasive method for the early detection of left ventricular dysfunction in symptom free patients with aortic regurgitation.

Noninvasive estimation of left atrial pressure in patients with congestive heart failure and mitral regurgitation by Doppler echocardiography.

A completely noninvasive method for estimating left atrial pressure in patients with congestive heart failure and mitral regurgitation has been devised with the use of continuous-wave Doppler echocardiography and brachial sphygmomanometry. Of 46 patients studied with mitral regurgitation, 35 (76%) had jets with distinct Doppler spectral envelopes recorded. The peak ventriculoatrial gradient was obtained by measuring peak mitral regurgitant velocity in systole and using the modified Bernoulli equation. This gradient was then subtracted from peak brachial systolic blood pressure, an estimate of left ventricular systolic pressure, to yield left atrial pressure (left atrial pressure = systolic blood pressure - mitral regurgitant pressure gradient). Noninvasive estimates of left atrial pressure from 35 patients were plotted against simultaneous recordings of mean pulmonary capillary wedge pressure resulting in the correlation y = 0.88x + 3.3, r = 0.88, standard error of estimate = +/- 4 mm Hg (p less than 0.001). Therefore, continuous-wave Doppler echocardiography and sphygmomanometry may be used in selected patients with congestive heart failure and mitral regurgitation for noninvasive estimation of left atrial pressure.