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Biomedical subjects

M Wada

Publications and source records attributed to M Wada.

At least 721 records · Page 40Linked to original sources
PubMed1977

Studies on a beta-migrating high density lipoprotein.

An unusual serum lipoprotein (Lp) profile was detected in a Japanese family. A double beta-Lp was observed when serum was subjected to polyacrylamide gel electrophoresis. The slower migrating beta-Lp was identified as a subfraction of high density lipoprotein (HDL). It was present in the d 1.063--1.21 fraction, migrated to the position designated as the midband L.1 (sinking pre-beta-lipoprotein) by Mead, M.G. and Dangerfield, W.G. (1974) (Clin. Chim. Acta 51, 173--182) [1], and reacted against human anti-beta-Lp antiserum. This lipoprotein contained greater amounts of triglyceride than the usual beta-lipoprotein and could not be clearly detected by paper electrophoresis. Individuals exhibiting this high density midband lipoprotein appeared to be heterozygous for an autosomal dominant gene. Although other reports have indicated the possibility of a positive association between the occurrence of serum lipoproteins with unusual eletrophoretic mobility and premature ischemic heart disease, no such correlation was demonstrable in these subjects.

Adolescent↗
PubMed1977

Diagnosis of right ventricular infarction: experimental study through the use of body surface isopotential maps.

This investigation was designed to diagnose right ventricular infarction, which is difficult to diagnose by the standard twelve-lead ECG, through the use of body surface isopotential maps which have significant diagnostic information. Right ventricular infarction was experimentally caused by ligation of the canine right coronary artery. Each dog had a series of maps recorded before and a week after experimentally-induced myocardial infarction. The common features of maps in right ventricular infarction are: 1. In the early stage of the ventricular depolarization the negative area occupies a comparatively large part of the right anterior chest surface, and in the middle stage, the larger part of the right anterior surface is also occupied by the negative area. 2. A minimum appears on the right anterior chest surface in the early stage. The delayed excitation resulting from intraventricular conduction disturbance caused by infarction, as verified by the epicardial isochronic map, is also well represented by the body surface isopotential map. In conclusion, through the use of body surface isopotential maps, it is much easier to diagnose right ventricular infarction and intraventricular conduction disturbance caused by infarction even in cases in which the standard twelve-lead ECG does not show the abnormalities clearly.

Animals↗
PubMed1977

Experimental study of myocardial infarction through the use of body surface isopotential maps: ligation of the anterior descending branch of the left coronary artery.

This investigation was undertaken to diagnose the location and extent of myocardial infarction with the use of maps which give significant information about the ventricular activation process. Myocardial infarction was experimentally caused by ligation of the anterior descending branch of the left coronary artery. All classes were classified into three groups (A,B, and C) according to the location and extent of infarction. The map of each group had its own characteristics, as follows. In Group A no pisitive potentials appeared on the left anterior chest surface all through ventricular depolarization. In Group B, like Group A, the negative area occupied the whole left anterior chest surface in the early stage. But in the later stages there appeared a positive area on the left anterior surface. As to Group C, there was no abnormality in its early stage, but in its middle stage, the negative area was found on the left anterior chest surface. Thus the sequential maps can be helpful in diagnosing the location and extent of myocardial infarction, and will be applied to clinical use much more.

Animals↗
PubMed1977

Diagnosis of high posterior infarction: experimental study through the use of body surface isopotential maps.

This investigation was designed to diagnose high posterior infarction easily through the use of body surface isopotential maps. High posterior infarction was experimentally caused by ligation of the branch of the circumflex artery of the canine left coronary artery. Each dog had a series of maps recorded before and four weeks after experimentally induced myocardial infarction. The common features of maps in high posterior infarction are: 1) The positive area expanded into the dorsal surface so slowly that, in the middle stage of the ventricular depolarization, a large area of the dorsal surface was still covered by the negative area. 2) from the middle to the late stage, the absolute value of the minimum significantly decreased and absolute potential of the dorsal surface also significantly decreased. In conclusion, we propose that it is possibile to diagnose high posterior infarction through the use of maps.

Animals↗
PubMed1977

Genesis of body surface potential distribution in right bundle branch block.

In order to investigate the specific sites of conduction block in the three types (I, II, III) of right bundle branch block (RBBB) classified by body surface isopotential maps, the simulation of ventricular propagation process and mathematically reconstructed maps were used. Four assumptions were introduced from the results of clinical observations and animal experiments. The maps reconstructed from two of these assumptions, in which the conduction block was placed on the main stem of the right bundle branch, showed two different patterns at late stages of excitation, and these two kinds of map resembled Types I and II in clinical maps, respectively. The maps reconstructed from the other two assumptions, in which the site of the conduction block was located mainly in the Purkinje system of the right ventricular free wall, resembled Type I at the late stage of excitation in one of two assumptions and agreed with Type III through all stages of excitation in other case. Based on the above results, it is speculated that the differences of ranges and degrees of conduction block ascribed to abnormal activation in the Purkinje system of the right ventricular free wall are responsible for the genesis of clinical RBBB map patterns.

Bundle-Branch Block↗
PubMed1977

Body surface potential distribution following the production of right bundle branch block in dogs. Effects of breakthrough and right ventricular excitation on the body surface potentials.

Right bundle branch block (RBBB) was produced in five dogs by incising the main right bundle branch. Body surface isopotential maps of each of these dogs were obtained from 85 thoracic electrocardiograms using a mini-computer technique. In addition, the epicardial activaton process was obtained from the same dog, and were correlated with the map pattern. Following the incision, the following characteristic changes in the map pattern occurred: The ventricular activation was prolonged in RBBB as compared with normal. During the early stage of ventricular excitation, the maximum was shifted leftward due to the activation wavefronts in the left ventricle in contrast to the double septal activation in the control. A localized lower potential area (a concavity) which appears in the middle stage of activation within the anterior positivity as an initial representation of breakthrough was also shifted left-and-downward and delayed in appearance. The sudden change in the potential distribution subsequently observed occurred quite differently. The terminal excitation was characterized by the maximum occurring over the right chest in RBBB in contrast to the left chest in control. These changes in the pattern of the potential distribution were compatible with the changes in the ventricular excitation process. This result may be applied to human RBBB map interpretation.

Action Potentials↗
PubMed1977

A female case of Kallmann's syndrome.

A case of 20-year-old woman with hypogonadotropic hypogonadism and anosmia is reported, since very few female cases of Kallmann's syndrome have been reported so far in Japan. Three uncles on the father's side had no children. Height was 168 cm, and arm span 165 cm. The olfactory test revealed complete anosmia. Bone age was 13 year. Chromosome was 46 XX and normal karyotype. Basal levels of serum FSH, LH and estrogens (E1, E2 and E3) were low. Serum FSH and LH levels rose slightly only after LH-RH administration, and did not increase in clomiphene test. Plasma estrogens did not increase after daily injection of 150 IU of HMG for 3 successive days. The response of serum GH to arginine infusion was normal, while that to insulin-induced hypoglycemia was poor.

Adult↗