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Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 289 records · Page 16Linked to original sources
PubMed1994

[Acute dissection of the interatrial septum after re-replacement of the mitral valve--a case report].

A 64-year-old man who had received a Carpentier-Edward mitral valve replacement seven years earlier was seen with dyspnea on exertion. After re-replacement of the mitral valve with SJM prosthesis, the patient developed acute left-sided heart failure on the third postoperative day. Transesophageal echocardiography revealed abnormal lumen posterior to the left atrium with regurgitant flow from the left ventricle. Right and left atriotomy revealed dissection of the interatrial septum and after removal of the prosthesis, communication between the left ventricle and the dissected lumen was recognized. After closing the communicating orifice, SJM prosthesis was again sutured on the mitral annulus with sub-annular pledgets to reinforce the annular attachment. Excessive debridement of the annular tissue was thought to be a causative factor to develop the dissection of the interatrial septum after mitral valve replacement.

Acute Disease↗
PubMed1994

Radioiodine uptake by squamous-cell carcinoma of the lung.

A patient with a history of total thyroidectomy for papillary carcinoma showed a solitary hot spot in the chest on post-therapy radioiodine imaging. Subsequent evaluation demonstrated that this lesion was a primary squamous-cell lung cancer. Our case illustrates a rare but important differential diagnosis from lung metastasis of thyroid cancer in 131I scintigraphy. Alternatively, this "aberrant uptake" might be a rather common phenomenon for lung neoplasms, although the underlying mechanism is not yet known. Future experimental studies might lead to a new application of radioiodine imaging in pulmonary oncology.

Adenocarcinoma, Papillary↗
PubMed1994

[Evaluation of clinical usefulness of 11C-methionine positron emission tomography (11C-MET-PET) as a tool for liver functional imaging].

We studied 11C-MET-PET in 17 clinical cases, 10 patients with obstructive jaundice and 7 normal volunteers, and analyzed its efficacy for the evaluation of hepatic functional reserve in major hepatectomy candidates. Differential absorption ratio (DAR) of 11C was compared to the hepatic protein synthesis rate (HPS), which is measured as the incorporation rate of 3H-labeled leucine in protein fraction, using needle biopsied liver specimen obtained from each hepatic segment. In the cases of normal liver function, DAR was well correlated with HPS. Also in jaundice cases with two exceptions, low HPS segment was demonstrated as low DAR segment. Consequently, MET-PET images could clearly provide functional liver imaging. After injection to 11C-MET, the increase in rate of radioactivity of 11C in plasma protein fraction was higher in jaundice cases than in normal volunteers, which is in accord with the results of our former study that cholestatic liver has accelerated protein synthesis rate. In summary, since 11C-MET-PET could demonstrate liver functional imaging, it might be a possible tool for liver function assessment in major hepatectomy candidates.

Carbon Radioisotopes↗
PubMed1994

Clinical application of evoked spinal cord potentials elicited by direct stimulation of the cord during temporary occlusion of the thoracic aorta.

Evoked spinal cord potentials elicited by direct stimulation of the cord were used to monitor spinal cord ischemia in 68 patients undergoing temporary occlusion of the thoracic aorta (29 thoracic nondissecting aortic aneurysms, 9 nondissecting thoracoabdominal aneurysms, and 30 dissecting aneurysms). "Immediate" postoperative paraplegia developed in three patients and "immediate" paraparesis developed in one, whereas "delayed" paraplegia developed in two others. During aortic crossclamping, four response patterns of the spinal cord potentials were obtained: (1) no change (n = 53), (2) change with return (n = 10), (3) change with inconsistent return (n = 2), and (4) change without return (n = 3). Neurologic complications occurred in 2%, 0%, 100% of these groups, respectively. Delayed paraplegia developed on the second postoperative day in only one patient with a false-negative result, and the potentials correlated well with this patient's clinical neurologic recovery. The aortic crossclamp time was significantly longer in the patients with "change with inconsistent return" and "change without return" than in the other two groups (p < 0.01). Femoral artery pressure and the cardiopulmonary bypass flow rate were also significantly lower in these groups than in the other two groups (p < 0.02 and p < 0.01, respectively). We conclude that intraoperative monitoring of direct spinal cord responses is useful for the early detection of spinal cord ischemia for assessing the efficacy of surgical countermeasures.

Aortic Dissection↗
PubMed1994

[Experience of reoperations followed by repairs of abdominal aortic aneurysms].

We experienced 8 cases who required reoperations, including 2 re-redo operations, after repairs of infrarenal abdominal aortic aneurysms. Of 8 patients, one patient developed a new aneurysm due to atherosclerosis in thoraco-abdominal aorta involving all visceral arteries and other 7 patients had aneurysmal formations at proximal anastomotic sites, including 3 suprarenal, 2 juxtarenal and 2 infrarenal aortic lesions. Etiology at initial operation in patients who subsequently developed anastomotic aneurysms included vasculo-Behçet disease in 4, atherosclerosis in 2 and dissecting aortic aneurysms type III due to Marfan syndrome in 1. At reoperation, all who had vasculo-Behçet disease had ruptures of anastomotic sites and 2 patients underwent repairs of dehiscent patch, 1 extra-anatomic bypass between ascending and abdominal aorta and 1 interposition of graft. One patient who had graft infection after repair of abdominal aortic aneurysm required axillo-femoral bypass with removal of infected graft. A patient who had dehiscence of proximal anastomosis after repair of aortoiliac occlusive disease required interposition of graft. Two patients, Marfan syndrome and aneurysm in thoraco-abdominal aorta, underwent graft replacement of thoraco-abdominal aorta concomitant with reconstruction of all visceral arteries. There were 8 patients who required reoperations for aneurysms at distal anastomotic sites after repairs of abdominal aortic aneurysms. Five patients underwent repairs of new aneurysms, including replacement of total arch in 3, descending aorta in 1 and iliac artery in 1. In all cases, no hospital death was noted, however, late deaths were occurred in vasculo-Behçet disease, Marfan syndrome and graft infection. Thus, late result depends on etiology of disease. Although patients who requires reoperation after repair of abdominal aortic aneurysms have higher operative risk factors, early and late results are satisfactory compared to initial operations.

Adult↗
PubMed1993

Purification of chondroitin 6-sulfotransferase secreted from cultured chick embryo chondrocytes.

Chondroitin 6-sulfotransferase, which transfers sulfate from 3'-phosphoadenylyl sulfate to position 6 of N-acetylgalactosamine in chondroitin, was purified 1,430-fold to apparent homogeneity with a 22% yield from the serum-free culture medium of chick embryo chondrocytes by affinity chromatography on heparin-Sepharose CL-6B, wheat germ agglutinin-agarose, and 3',5'-ADP-agarose. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme showed a single broad protein band with an apparent molecular weight of 75,000. Since the purified enzyme has an apparent molecular weight of 160,000 as judged by gel chromatography on Superose 12, the active form of chondroitin 6-sulfotransferase may be a dimer. The purified enzyme transferred sulfate to chondroitin, chondroitin sulfate, and corneal keratan sulfate. Chondroitin sulfate E from squid cartilage, dermatan, sulfate, and heparan sulfate hardly served as acceptors of the sulfotransferase. The sulfated product derived from keratan sulfate was degraded by keratanase but not by chondroitinase ABC.

Animals↗
PubMed1993

Childhood myelodysplastic syndrome with clonal evolution progressing to acute megakaryoblastic leukemia (ANLL-M7).

We treated a 16-month-old girl with myelodysplastic syndrome (MDS; refractory anemia with excess of blasts subtype, RAEB by FAB classification) that developed into acute megakaryoblastic leukemia (ANLL-M7). The blast cells were positive for CD41 shown by flow cytometry and for platelet peroxidase by electron microscopy. Cytogenetically, five kinds of abnormal karyotypes were apparent at the initial visit and karyotypic progression (clonal evolution) was also evident. These karyotypes were considered to be derived from the putative original clone, 48,XX, +6, +21. The observed karyotypes were considered 50,XX, +4,add(4)(q31), +6,add(7)(p22),add(10)(q24),add(12)(q11), +20, +21, + mar[karyotype A];48,XX,add(4)(q31), +6,add(10)(q24),add(12)(q11), +21 [karyotype B];48,XX, +6,t(6;13)(p23;q14), +21 [karyotype C];51,XX, +X, t(6;13)(p23;q14), + der(6)t(6;13)(p23;q14), +21, +21, + mar [karyotype D]; and 49,XX, +X, -3,t(6;13)(p23;q14), +der(6)t(6;13)(p23;q14), -12, +21, +21, + mar [karyotype E]. It seems karyotypes B and C were derived from the putative clone; karyotype B developed into karyotype A; and karyotype C developed into karyotype E through karyotype D. After development of ANLL-M7, the cytogenetic study showed a karyotype with further karyotypic progression. The patient was treated with high-dose cytosine arabinoside (HD AraC) followed by allogeneic bone marrow transplantation. Despite intensive care, she died 3 months after the transplantation.

Anemia, Refractory, with Excess of Blasts↗
PubMed1993

The putative phosphoinositide-specific phospholipase C gene, PLC1, of the yeast Saccharomyces cerevisiae is important for cell growth.

Using the polymerase chain reaction technique, we have isolated a gene that encodes a putative phosphoinositide-specific phospholipase C (PLC) in the yeast Saccharomyces cerevisiae. The nucleotide sequence indicates that the gene encodes a polypeptide of 869 amino acid residues with a calculated molecular mass of 101 kDa. This polypeptide has both the X and Y regions conserved among mammalian PLC-beta, -gamma, and -delta, and the structure is most similar to that of mammalian PLC-delta. This putative yeast PLC gene has been designated PLC1. Disruption of PLC1 results in slow growth or lethality for cells, depending on their genetic background and the medium, indicating that PLC1 is important for cell growth. Expression of rat PLC-delta 1 cDNA suppressed the growth defect of plc1 disruptants, strongly suggesting that PLC1 encodes PLC.

Amino Acid Sequence↗
PubMed1993

Three yeast genes, PIR1, PIR2 and PIR3, containing internal tandem repeats, are related to each other, and PIR1 and PIR2 are required for tolerance to heat shock.

We isolated three highly homologous genes, PIR1, PIR2 and PIR3, collectively called the PIR genes. The remarkable feature of their putative amino acid sequence is that they contain a sequence consisting of 18-19 amino acid residues repeated tandemly seven to ten times. Genes homologous to PIR were found in Kluyveromyces lactis and Zygosaccharomyces rouxii but not in Schizosaccharomyces pombe, suggesting that a set of PIR genes plays some role in budding yeast. Bias of codon usage seen in each of the PIR translation products suggests that they are expressed abundantly. The fact that disruption of each gene is viable indicates that none of them is essential. The double disruptants, pir1 pir2, were viable under various conditions, such as higher temperature (37 degrees C) or high salt concentration, but showed a slow-growing phenotype on an agar slab. Furthermore, they were sensitive to heat shock. Addition of a pir3 disruption to the pir1 pir2 double disruptant brought about no phenotypic difference from the original double mutant. PIR1 and PIR3 are closely linked to each other and are on chromosome XI.

Amino Acid Sequence↗
PubMed1993

MSI3, a multicopy suppressor of mutants hyperactivated in the RAS-cAMP pathway, encodes a novel HSP70 protein of Saccharomyces cerevisiae.

The MSI3 gene was isolated as a multicopy suppressor of the heat shock-sensitive phenotype of the ira1 mutation, which causes hyperactivation of the RAS-cAMP pathway. Overexpression of MSI3 also suppresses the heat shock-sensitive phenotype of the bcy1 mutant. Determination of the DNA sequence of MSI3 revealed that MSI3 can encode a 77.4 kDa protein related to the HSP70 family. The amino acid sequence of Msi3p is about 30% identical to that of the Ssa1p of Saccharomyces cerevisiae. This contrasts with the finding that members of the HSP70 family generally show at least 50% amino acid identity. The consensus nucleotide sequence of the heat shock element (HSE) was found in the upstream region of MSI3. Moreover, the steady-state levels of the MSI3 mRNA and protein were increased upon heat shock. These results indicate that the MSI3 gene encodes a novel HSP70-like heat shock protein. Disruption of the MSI3 gene was associated with a temperature sensitive growth phenotype but unexpectedly, thermotolerance was enhanced in the disruptant.

Amino Acid Sequence↗
PubMed1993

Thalamic- and cerebellar-projecting interpolaris neuron responses to afferent inputs.

Thalamic- and cerebellar-projecting interpolaris neuron responses to afferent inputs from the temporomandibular joint (TMJ) and/or the masseter muscle (Mm) were examined in rats. Of 230 neurons tested, 24 could be antidromically stimulated from the contralateral ventral posteromedial thalamic nucleus (VPM), and 27 of 91 neurons tested were stimulated from the ipsilateral posteromedial part of crus II of the cerebellar cortex. None had dual projections. The thalamic-projecting neurons were recorded in the dorsomedial region of the interpolaris; most cerebellar-projecting neurons were at the medial border of the interpolaris. Ten of 24 thalamic- and 17 of 27 cerebellar-projecting neurons received nociceptive information. Afferent inputs from the TMJ and the Mm converged on 6 of 24 thalamic-projecting neurons and on 16 of 27 cerebellar-projecting neurons. In both the thalamic- and cerebellar-projecting neurons, there was no difference between the non-nociceptive and nociceptive neurons in mean antidromic latency. The results suggest that the interpolaris integrates and relays afferent inputs from deep oral structures.

Afferent Pathways↗