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H Tanahashi

Publications and source records attributed to H Tanahashi.

8 recordsLinked to original sources
PubMed1992

Takayasu's arteritis with collateral circulation from the right coronary artery to intracranial vessels--a case report.

A forty-four-year-old woman with Takayasu's arteritis and involvement of the aortic arch and its main branches complained of precordial pain on effort. Exercise electrocardiograms revealed significant ST segment depression in leads II, III, aVF, and V. Coronary arteriograms demonstrated no stenosis. However, the right coronary arteriogram revealed collateral circulation arising from the sinus node artery to the bilateral vertebral arteries and the left internal carotid artery. The collateral circulation was considered to be an important route of blood flow supply to the brain and, at the same time, a cause of coronary steal syndrome and, consequently, of angina pectoris.

Adult↗
PubMed1991

[A case of aortitis syndrome with coronary steal syndrome due to collateral circulation from the right coronary artery to intracranial vessels].

A 44-year old female with aortitis syndrome complained of precordial pain on effort. Exercise electrocardiograms revealed significant ST segment depression in leads II, III, aVF and V. Coronary arteriograms demonstrated no stenosis. However, the right coronary arteriogram revealed collateral circulation arising from the sinus node artery to the bilateral vertebral arteries and the left internal carotid artery. Collateral vessels in aortitis.syndrome arising from the coronary artery to the lung have been reported sporadically. However, to our knowledge, the collateral circulation from the coronary artery to intracranial vessels as seen in the present case has never been reported. In the present case, the left ventricular hypertrophy was observed on electrocardiograms and echocardiograms. It can not be denied that it was a cause of the angina pectoris. However, exercise myocardial scintigraphy showed transient myocardial ischemia at stress on the inferoposterior wall corresponding to leads II, III, aVF and V on electrocardiograms. Therefore, coronary steal syndrome due to the collateral pathway from the coronary artery may be considered a likely cause of the angina pectoris. The collateral circulation was considered to be an important route of blood flow supply to the brain and, at the same time, a cause of coronary steal syndrome and consequently angina pectoris.

Adult↗
PubMed1990

Photoprotein aequorin: use as a reporter enzyme in studying gene expression in mammalian cells.

Aequorin is a luminescent protein present in the jellyfish Aequoria victoria which emits light (at 460 nm) in the presence of Ca2+. We report here that aequorin can be used as a reporter enzyme to monitor gene expression in eukaryotic cells. A cDNA encoding apoaequorin was fused to several eukaryotic promoters, including those of SV40, RSV and the HSV-1 tk gene, and introduced into several cell lines such as CV-1, COS and HeLa. At appropriate times after transfection, the aequorin activities in cell extracts were measured by monitoring the intensity of light emitted at 460 nm when triggered by Ca2+ by the use of a photomultiplier photometer. The aequorin assay was shown to be as sensitive as the conventional CAT assay, and the relative activities of various promoters estimated by the aequorin assay were in general agreement with those obtained by the CAT assay. The aequorin assay can be done within 6-7 h from the preparation of extract to the measurement of activity without using radioactive compounds.

Aequorin↗
PubMed1990

[A case of primary coronary artery dissection].

Primary coronary artery dissection occurring as a spontaneous event and not associated with trauma due to catheter manipulation is rare. We recently experienced (a case of) a 52-year-old man with primary artery dissection. He was admitted to our hospital with severe chest pain as his chief complaint on September 6, 1988. Electrocardiography and laboratory data showed acute inferior myocardial infarction. He was treated with medication and underwent coronary angiograms on October 3, 1988. Right coronary angiogram revealed an intimal flap and false lumen. But right coronary angiograms 6 months after the onset of myocardial infarction revealed progression of stenosis but no intimal flap, and coronary spasm was not evoked after acetylcholine administration. Primary coronary artery dissection has been reported since Pretty's first description of it in 1931. The majority of earlier cases were diagnosed at autopsy, but recently reports of survivors have been increasing due to the progress in and popularization of coronary angiographic technics. This case is the 46th case of primary coronary dissection found by coronary angiography. So it is not extremely rare. In our case the involved artery was the right coronary artery. In survivors, right coronary artery dissection is more frequent than left, because the area supplied by the right coronary artery is smaller than the area supplied by the left one. Although in our case coronary artery stenosis progressed, after a long term resolution of dissection may occur. There are a few cases in which resolution of dissection occurred naturally.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Dissection↗
PubMed1989

Nuclear factors interacting with an interleukin-6 responsive element of rat alpha 2-macroglobulin gene.

During acute inflammation, a group of liver-derived plasma proteins, acute phase proteins (APPs), increase in concentration. Interleukin-6 (IL-6) is responsible for this increase via the induction of APP gene expression. We have identified an IL-6 responsive cis-acting element (IL-6RE) of gene encoding a typical APP, rat alpha 2-macroglobulin (alpha 2M). The IL-6RE contains a sequence that is conserved among the 5'-flanking regions of various APP genes. Introduction of mutations into the conserved sequence revealed that the sequence, termed IL-6RE core, is a critical and essential component of IL6-RE. Nuclear factors binding to the IL-6RE core were identified in livers of normal and inflamed rats. Mobility shift pattern and DNase I footprinting profile indicated that the factors from normal and inflamed stages recognized the same sequence but were distinct from each other. These results suggested that the regulation of alpha 2M gene expression may involve mutually exclusive interaction of stage-specific trans-acting factors.

Animals↗
PubMed1989

Human transthyretin (prealbumin) gene and molecular genetics of familial amyloidotic polyneuropathy.

Transthyretin (TTR, also called prealbumin) is a plasma protein produced in liver. The variant types of TTR are known to be closely associated with familial amyloidotic polyneuropathy (FAP), an autosomal dominant genetic disorder. This article summarizes, together with some new data, our current knowledge on FAP from the view point of molecular genetics. As an initial step towards understanding the disease at the DNA level, the complete nucleotide sequence of the human TTR gene (-7 kb to 7 kb; 1 kb = 10(3) bases) was determined and analyzed. The gene is located on chromosome 18 q12.1 and consists of four exons. Homology search revealed that there exist several possible regulatory signals in the 5' flanking region of the gene, including the binding sites for liver-specific nuclear factors HNF-1, 3, 4 and C/E BP, which have been previously identified in mouse TTR gene. Sequence analysis enabled us to identify all the mutations related to various types of FAP. The mutations were shown to be almost completely linked to FAP and it has become possible to diagnose FAP even at presymptomatic (prenatal) stages by recombinant DNA technology, with a high reliability. Haplotype analysis of FAP families using DNA polymorphic markers in the TTR locus suggested that the Val30----Met mutation closely related to type I FAP, the most common type of FAP, has frequently recurred in the human population to generate FAP families of independent origin. Although the primary cause of FAP has become clear, extensive screening of FAP families in various locations suggested that the expression of FAP is a complicated process and affected by some unknown factors (other than TTR).(ABSTRACT TRUNCATED AT 250 WORDS)

Amyloidosis↗
PubMed1986

Clinical experience with a new rate-responsive TX pacemaker.

In this report, we describe our initial experience with a new rate-responsive TX pacemaker in 10 patients. This pacemaker system uses a conventional transvenous ventricular electrode, which senses the evoked QT interval after a ventricular paced beat, as an indicator of physiological metabolic demand. Implantation of the TX pacemaker does not differ from that of conventional VVI units, and two special modes are available after implantation: TX and VVI mode. Bicycle ergometer tests showed that significantly higher rate response and exercise ability were achieved during the TX mode compared with the VVI mode (mean maximal heart rate: 115 +/- 13 bpm vs 96 +/- 21 bpm, p less than 0.01, and mean maximal exercise time; 10.7 +/- 3.9 min vs 8.0 +/- 3.8 min, p less than 0.01, respectively). In one patient, cardiac index was measured by a thermodilution method during the bicycle ergometer test, which confirmed that an adequate increase in cardiac index (rest: 3.38 liters/min/m2, vs exercise; 7.34 liters/min/m2) was obtained by an increase of the pacing rate (rest: 72 bpm vs exercise: 128 bpm). Our results show that physiological rate-responsive pacing using the QT interval provides a simple means of increasing the heart rate and cardiac index.

Aged↗