Observation of edge states derived from topological helix chains.

Introducing the concept of topology has revolutionized materials classification, leading to the discovery of topological insulators and Dirac-Weyl semimetals1-3. One of the most fundamental theories underpinning topological materials is the Su-Schrieffer-Heeger (SSH) model4,5, which was developed in 1979-decades before the recognition of topological insulators-to describe conducting polymers. Distinct from the vast majority of known topological insulators with two and three dimensions1-3, the SSH model predicts a one-dimensional analogue of topological insulators, which hosts topological bound states at the endpoints of a chain4-8. To establish this unique and pivotal state, it is crucial to identify the low-energy excitations stemming from bound states, but this has remained unknown in solids because of the absence of suitable platforms. Here we report unusual electronic states that support the emergent bound states in elemental tellurium, the single helix of which was recently proposed to realize an extended version of the SSH chain9,10. Using spin- and angle-resolved photoemission spectroscopy with a micro-focused beam, we have shown spin-polarized in-gap states confined to the edges of the (0001) surface. Our density functional theory calculations indicate that these states are attributed to the interacting bound states originating from the one-dimensional array of SSH tellurium chains. Helices in solids offer a promising experimental platform for investigating exotic properties associated with the SSH chain and exploring topological phases through dimensionality control.

Hypoglycemia associated with the production of insulin-like growth factor II in adrenocortical carcinoma.

A 78-year-old woman was hospitalized for congestive heart failure and repeated hypoglycemic attacks. The laboratory data showed a serum insulin level within the normal range and an increased level of serum insulin-like growth factor (IGF) II. Abdominal ultrasonogram and computed tomography scan revealed a huge mass lying above the left kidney. She was diagnosed as having an adrenocortical carcinoma. After the removal of the tumor, the plasma glucose level and the serum level of IGF-II were normalized. The tumor cells stained positively for IGF-II immunohistochemically. These findings suggested that the hypoglycemia was due to IGF-II produced by the adrenocortical carcinoma.

[Successful treatment using low-dose carbamazepine for a patient of personality change after mild diffuse brain injury].

A 19-year-old male had a traffic accident while driving his motorbike and suffered an injury to the left frontotemporal part of the head. He remained conscious, had no focal neurological signs, and brain-computed tomography was unremarkable at the prefectural hospital, department of neurosurgery. Six months later he demonstrated a personality change, which was marked by irritability, aggression, labile moods, childishness, irresponsibility, and a lack of motivation. He sometimes made trouble for those around him, and he consulted our hospital 2 years and 9 months after the accident. He was diagnosed as having posttraumatic personality disorder and was treated with clonazepam, a dosage of up to 1.5 mg/day. Although his symptoms were moderately improved, he complained of sleepiness as an adverse effect. Carbamazepine (100 mg/day) was added in expectation of further improvement. Within a few days he improved to his preaccident personality. After the administration of clonazepam was discontinued, he maintained his good mental status. Now about two years after the initiation of therapy, he works in social welfare facilities and has no relapses. Even if a head injury is mild without definite organic signs in brain, it may have a possibility of causing personality change, which may be treatable.

Dilated cardiomyopathy associated with hyperthyroidism.

We report a case of dilated cardiomyopathy with hyperthyroidism. A 28-year-old man was admitted because of congestive heart failure and atrial fibrillation, and was newly diagnosed as having hyperthyroidism. Despite administration of antithyroid medication, he developed recurrent congestive heart failure. An echocardiogram revealed a moderately dilated left ventricle with diffuse hypokinesis. Though his thyroid function normalized, the patient's cardiac dysfunction did not improve. Beta-blocker therapy was begun with subsequent improvement in clinical symptoms. This suggests that beta-blocker treatment may be effective in patients with atrial fibrillation associated with cardiomyopathy and hyperthyroidism.

[Evaluation of left ventricular systolic function by pulsed Doppler echocardiography in patients with acute myocardial infarction].

Left ventricular systolic function in patients with acute myocardial infarction was assessed by Doppler echocardiographic measurement of left ventricular ejection flow velocity and maximum acceleration in 20 patients with initial acute anteroseptal myocardial infarction (group A) and 15 age-matched normal subjects. All patients underwent emergency reperfusion therapy by direct percutaneous transluminal coronary angioplasty (direct PTCA). Pulsed Doppler echocardiograms were obtained from sample volume immediately below the aortic valve in the apical long-axis view. Three parameters, peak velocity, ratio of acceleration time to ejection time (AT/ET) and maximum acceleration, were measured by the Doppler analysis program. Changes in the 3 parameters from the day of admission to the 3rd post-admission day were also observed in 15 patients. Although no significant difference was observed in AT/ET in the 2 groups, peak velocity and maximum acceleration in the patient group were significantly lower than those in the normal group (peak velocity: 90.8 +/- 13.1 vs 99.4 +/- 9.7 cm/sec, p < 0.05, maximum acceleration: 2,692.4 +/- 604.5 vs 3,410.2 +/- 712.5 cm/sec2, p < 0.01, respectively). Between the admission and 3rd day, peak velocity and AT/ET did not change significantly, but maximum acceleration increased significantly (2,720.5 +/- 676.7, 1st day vs 3,313.9 +/- 947.5 cm/sec2, 3rd day, p < 0.05). These results indicate that the maximum acceleration measured by pulsed Doppler echocardiography is useful for assessing global left ventricular systolic function in acute myocardial infarction. Direct PTCA results in improved ventricular systolic function on the 3rd post-operative day.

[Continuity from normal to prolapsed mitral valves: two-dimensional and color Doppler echocardiographic investigations].

To investigate the continuity between the normal and prolapsed mitral valves (MVP), two-dimensional echocardiography (2DE) and color Doppler echocardiography (CDE) were performed in 508 healthy boys aged 12 to 13 years old. The distance from the plane of the mitral annulus to the coaptation of the mitral valve "c", the maximum distance between the anterior leaflet and a straight line connecting the anterior mitral annulus and the coaptation of the mitral valve "d", and the maximum distance between the posterior mitral leaflet and the straight line connecting the posterior mitral annulus and the coaptation of the mitral valve "e" were measured in the parasternal long-axis view. The locations of the anterior and posterior mitral annuli were determined to be the hing point of the anterior leaflet on the left ventricular side and the junction of the posterior leaflet on the ventricular side, respectively. Mitral regurgitation (MR) was evaluated by CDE in the parasternal long-axis view. The ratio of the duration of regurgitation to ejection time (DT/ET) was measured by M-mode CDE in the subjects with and without MVP. The values of "c" ranged from +10 mm to -3 mm, and those of "d" from +5 mm to -4 mm (minus denotes prolapse into the left atrium). Approximately normal distributions were demonstrated with the parameters "c" and "d". The value of "e" could not be measured because of a poor image of the posterior leaflet. The incidence of MVP varied from 2.5 to 13.5% depending on the criterion for applied MVP. Fifty-nine of the 487 healthy subjects turned out to have MR (12%). Coaptation of the mitral valve deviated from the posterior commissure significantly to the left atrium more in the subjects with MR than in those without MR (2.46 +/- 1.93 vs 3.41 +/- 1.84, p < 0.01). The DT/ET ratio of the MR subjects with MVP tended to be higher than that of the boys without MVP. The presence of continuity between the normal and prolapsed mitral valves suggests that MVP may be a multifactorial disorder of the valve. Associated asymptomatic MR may be related not only to the severity of MVP but also to other factors, especially in MR of normal healthy subjects.

[Continuity of normal and prolapsed mitral valves: two-dimensional and color Doppler echocardiographic investigations].

To certify the continuity between the normal and prolapsed mitral valves (MVP), two-dimensional and color Doppler echocardiography (2-DE and CDE) were performed for healthy 250 male subjects of 13 years old. The distance from the plane of the mitral annulus to the coaptation (c) and the grade of systolic ballooning of the anterior mitral leaflet as expressed by the maximum distance between the leaflet and the straight line connecting the anterior mitral ring with the point of coaptation (d) were measured in the long-axis 2-DE. Mitral regurgitation (MR) was evaluated by CDE. Distribution of c was between +10 and -3 mm, and d was between +5 and -3 mm (minus denotes prolapse toward the left atrium). An approximately normal distribution was found in both parameters c and d. The incidence of MVP varied from 3 to 13% according to the strictness of the criteria for MVP. Subjects with MR from the posterior commissure showed the coaptation significantly displaced toward the atrium compared with the rest of subjects (p less than 0.01). Our data suggest that MVP is a multifactorial disorder of the valve and the development of MR has some relation to the severity of MVP.