PubMed Health⌕ Search

Biomedical subjects

K Hashiba

Publications and source records attributed to K Hashiba.

At least 145 records · Page 8Linked to original sources

Correction of hypertension by partial nephrectomy in segmental renal artery stenosis and electron microscopic studies of renin.

An 18-year-old man had hypertension with hyperreninemia and marked difference in plasma renin activity between both renal veins after tilting. Selective renal arteriography revealed a stenotic lesion in a segmental artery to the upper pole of the left kidney with poststenotic dilatation. The upper pole of the kidney with abnormal arterial segment was resected and the blood pressure returned to normal. Electron microscopically, a large number of mature juxtaglomerular cell granules were associated with many protogranules in the epitheloid cell. These findings suggest that his hypertension was due to overproduction of renin from the upper pole.

Adolescent↗

Release of active and inactive renin by the human kidney.

1. Active and inactive renin were assayed in plasma of the renal veins and the inferior vena cava below the kidney in eight patients with hypertension and unilateral renal abnormalities, 20 min after the patients had resumed the upright position. 2. The concentration of active renin on the affected side was significantly higher than that on the non-affected side. The concentration of inactive renin on the affected side was significantly lower than that on the non-affected side and in the inferior vena cava. 3. These findings suggest either that the affected kidney mainly secretes active renin, which is then converted into inactive renin in the extrarenal circulation, or that the affected kidney activates inactive renin.

Enzyme Activation↗

Enzyme immunoassay of angiotensin I.

A very sensitive and specific enzyme immunoassay has been developed for angiotensin I. Angiotensin I was coupled to beta-D-galactosidase by a novel cross-linking reagent, N-(meta-maleimidobenzoyloxy)succinimide. No decrease in the enzyme activity was observed during the coupling procedure. In the angiotensin I-beta-D-galactosidase conjugate, 0.39 mol immunoreactive angiotensin I/mol enzyme were present. A competitive assay with the enzyme-labeled angiotensin I was performed. Antibody-bound and free labeled antigen were separated from each other by the second antibody method, and the enzyme activity of the former was estimated. Using this assay, angiotensin I could be detected in the range of 1.2--50 pg. The sensitivity was 4.5-fold higher than that of the usual RIA. This assay distinguished clearly angiotensin I from angiotensin II, angiotensin III, and (Sar1, Ile8)-angiotensin II. The present method was applied to measure PRA in dogs; the results correlated fairly well with those obtained by the RIA (r = 0.94).

Angiotensin I↗

Systolic time intervals in progressive muscular dystrophy.

Indirect systolic time intervals corrected for heart rate were measured at rest, during, and immediately after the isometric handgrip exercise in 70 patients with progressive muscular dystrophy, and these were compared with the values of normal subjects. Those with dystrophy included 47 patients with Duchenne type, 19 with limb girdle type and 4 with facioscapulohumeral type, and each type was subdivided into 2 groups by the severity of the skeletal muscle involvement: 1) mild group, included patients who were still able to walk, 2) severe group, included those who were restricted to wheel chair or confined to bed. Over a half of the patients of the severe Duchenne type group had a longer pre-ejection period (PEP), shorter left ventricular ejection time (LVET), and larger PEP/LVET ratio at rest than the normal group. Increased PEP/LVET ratio during and after isometric handgrip exercise was observed in the severe group of Duchenne type. The patients with limb girdle type, and facioscapulohumeral type showed no significant difference in values of the systolic time intervals at rest and during handgrip exercise compared with the normal subjects. The measurements of resting and exercise systolic time intervals may be useful for clinical recognition of latent left ventricular functional impairement in subjects with progressive muscular dystrophy.

Adolescent↗

Long-term follow-up after cardiac pacing in bradyarrhythmias.

Fifty-nine patients aged 39-80 years underwent implantation of a cardiac pacemaker and were followed for up to 9 years (average duration of pacing 39 months). Atrioventricular conduction disturbances (complete atrioventricular block, 2 : 1 atrioventricular block, bifascicular block, and atrial fibrillation with slow ventricular rate) were present in 49 patients and sick sinus syndrome (sinus arrest or sino-atrial block, and bradycardia-tachycardia syndrome) in 10. Pacing was required because of Adams-Stokes attacks in 41 patients, 2 of whom also had congestive heart failure. It was required in 6 because of frequent dizziness, in 10 because of congestive heart failure, and in 2 because of low cardiac output. The symptomatic improvement after cardiac pacing was well recognized in most of our patients, and 32 (54 percent) of the 59 patients pursued normal physical and daily activity. Although the efficacy of pacemaker therapy was of limited value in some patients with congestive heart failure or underlying or coexisting diseases, the beneficial effects following pacemaker implantation were: (1) abolishment of transient neurologic symptoms such as Adams-Stokes attack, (2) relief from a constant fear of a recurrence of an Adams-Stokes attack or sudden cardiac death, and (3) improvement in restricted physical activity due to low cardiac output. Thus, we conclude that pacemaker implantation in most patients with bradyarrhythmias is beneficial not only for the treatment of the acute problem but also because it prolongs life and greatly enhances its quality. However, in spite of the beneficial effects after pacemaker implantation, we still observe a number of complications connected with the use of a permanent pacemaker. Therefore, our policy is to implant a permanent pacemaker following the execution of sufficient studies of the bradyarrhythmia and the etiology of symptoms, and then under taking long-term follow-up of the patients.

Adult↗