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Biomedical subjects

K Morishita

Publications and source records attributed to K Morishita.

At least 19 recordsLinked to original sources
PubMed2005

Heterogeneity of platelet responsiveness to anti-CD36 in plasma associated with adverse transfusion reactions.

BACKGROUND AND OBJECTIVES: Antibodies to CD36 (anti-CD36) are clinically important. As some platelet immunoglobulins produced by transfusion or pregnancy have been shown to induce platelet activation and to play roles in non-haemolytic transfusion reactions (NHTRs), we investigated the in vitro response of platelets to plasma containing anti-CD36. MATERIALS AND METHODS: Plasma containing anti-CD36, implicated in the development of NHTRs and subsequent thrombocytopenia, was incubated with CD36-positive platelets. Plasma-induced platelet activation was examined by evaluating platelet aggregation and RANTES (regulated on activation, normal, T-cell expressed, and presumably secreted) release. RESULTS: Platelet activation was induced by plasma alone in four out of 20 CD36-positive subjects. In seven subjects, platelet activation was synergistically induced by the combination of epinephrine priming and the plasma. The platelets of the nine remaining subjects failed to respond to the plasma. Platelet activation induced by either the plasma alone or by synergy with epinephrine required the involvement of Fc gamma RIIa. The different responsiveness of the platelets was partially associated with the surface levels of CD36 and Fc gamma RIIa, but not with Fc gamma RIIa polymorphisms. CONCLUSIONS: Plasma containing anti-CD36, implicated in the development of NHTRs, exhibited a platelet-activating capability. Additionally, platelets from healthy human subjects exhibited a considerable degree of heterogeneity in their responsiveness to this plasma. The heterogeneity of these responses may determine the occurrence of anti-CD36-related NHTRs.

Antigens, CD↗
PubMed2004

Immediate hemodialysis after percutaneous transvenous angioplasty increases patency rates of arterio-venous fistula.

BACKGROUND: It was reported that pathogenesis of access failure of hemodialysis patients through progressive stenosis was followed by thrombosis. Nonionic contrast media increase platelet degranulation within an angioplasty-damaged vessel by releasing procoagulant molecules, which might contribute to acute thrombosis and restenosis. An adequate level of heparin provides satisfactory thrombin inhibition during routine angioplasty. This study was performed to evaluate the effect of immediate hemodialysis after percutaneous transvenous angioplasty (PTA) to remove nonionic contrast media or other factors while injecting heparin continuously. METHODS: From September 9, 1998 - May 15, 2002, successful PTAs were performed in 66 patients with arteriovenous fistula who were not given any inhibitors of platelet aggregation. Hemodialysis was performed in 31 cases immediately after PTA, and in the remainder, hemodialysis was performed the next day. Patients were randomized and fistula patency rates were compared in these 2 groups on March 20, 2004. RESULTS: The patency rates after PTA in patients who were dialyzed immediately, were significantly higher than those who were dialyzed the next day (p = 0.0120). CONCLUSIONS: Immediate hemodialysis after PTA is an effective way of increasing the patency of arteriovenous fistula for reasons which are not clear. This observation will need to be corroborated in subsequent studies using a larger sample size.

Aged↗
PubMed2004

[Thoracoabdominal aortic aneurysm repair after detection of the Adamkiewicz artery by magnetic resonance angiography; a way to shorten operating time and improve outcome].

Surgical results were compared between 18 patients (group A) who underwent preoperative anatomic characterization of the Adamkiewicz artery by magnetic resonance angiography (MRA) and 38 patients (group B) without such imaging. In group A, intercostal or lumbar arteries related to the aneurysm were reattached to the graft only when they represented the origin of the Adamkiewicz artery. In group B, reconstruction from the Th 7 intercostal and the L2 lumbar arteries was performed whenever possible. In-hospital mortality was 16.7% in group A and 15.8% in group B. Total aortic clamp time and operating time were only 84 and 437 min in group A, compared with 134 and 589 min in group B. Three patients showed postoperative paraplegia in group B. No spinal cord injury occurred in patients whose artery had been detected preoperatively. Preoperative anatomic delineation of the Adamkiewicz artery by MRA can reduce risk of ischemic injury to the spinal cord and decrease operating time required for repair of thoracoabdominal aortic aneurysms.

Adult↗
PubMed2002

[Minimal incision abdominal aortic aneurysm repair].

OBJECTIVE: The use of a limited incision for abdominal aortic aneurysm (AAA) repair was evaluated, and its outcome was analyzed in comparison to standard open repair. PATIENTS AND METHODS: Between February 2000 and August 2001, 20 patients with an AAA underwent minimal incision repair (MINI) for tube graft implantation. The minimal skin incision was made after localization of aneurysm neck and aortic bifurcation by CT and DSA. For repair of the upper part of the AAA the abdominal incision was retracted toward the head of the patient who was in a jackknife decubitus position. Conversely, when the peripheral portion of the AAA was treated, the abdominal incision was retracted caudally with the patient in a flat or slightly bent decubitus position. The operation itself was performed using the standard conventional technique. The length of the abdominal incision was 10 cm. Clinical characteristics and in-hospital outcome of this procedure were compared to a group of patients who underwent repair of AAA by means of a standard open technique (OPEN). RESULTS: Patients age in the MINI and OPEN groups were similar (69 +/- 11 vs. 69 +/- 9 years). However, there were significant differences between the MINI and OPEN groups in the time for starting oral intake of food (2,4 +/- 1,2 vs. 7,4 +/- 5,5 postoperative days, p = 0,003), time for starting to walk outside the room (2,2 +/- 0,7 vs. 4,6 +/- 2,2 postoperative days, p = 0,01) and operation times (197 +/- 37 vs. 294 +/- 83 min, p = 0,0004). CONCLUSION: Minimal incision repair is technically feasible and combines the benefits of a minimal incision with those of conventional open repair, reducing patient recovery time.

Aged↗
PubMed2002

[Esophageal rupture just after the graft replacement of thoracoabdominal aorta for chronic aortic dissection].

A 51-year-old man with thoracoabdominal aortic aneurysm (DeBakey IIIb type chronic aortic dissection) first underwent the graft replacement of thoracic aorta with elephant trunk technique. Postoperatively, the residual false lumen just distal to the inserted graft as an elephant trunk enlarged in a short period, and it compressed the esophagus. He underwent the second graft replacement of thoracoabdominal aorta 2 months after the first surgery. Just after the second surgery, he had the esophageal rupture probably because of direct damage due to the enlarged aneurysm and loss of the arterial blood supply due to the graft replacement. He died of bleeding from the distal anastomosis because of the uncontrolled graft infection. It may have to be kept in mind that the esophageal rupture after the graft replacement could be one of the reason of the graft infection when the aortic aneurysm severely compressed the esophagus preoperatively.

Aortic Dissection↗
PubMed2002

[Surgical treatment of cardiovascular manifestations of Marfan syndrome].

The present study determines the effect of surgical treatment of cardiovascular manifestations of Marfan syndrome in 72 patients by 114 operations, during 34-year period. This therapy resulted in aortic root repair, aortic arch replacement, or both in 78, mitral valve repair in 9, descending thoracic aortic replacement in 14, thoracoabdominal aortic replacement in 10, and abdominal aortic replacement in 6, including total aortic replacement in 4 and nearly total aortic replacement in 4 patients. Fusiform aneurysms were present in the the ascending aorta in 37, the aortic arch in 2, the thoracoabdominal aorta in 2, and the abdominal aorta in 6 patients. Aortic dissection occurred in 40 (55.6%), including type A aortic dissection in 29 patients. Aortic root repair included separate valve-graft in 8, Bentall composite valve-graft in 25, composite valve-graft with button technique in 26, composite valve-graft with interposition graft technique in 10, and valve sparing procedure in 5 patients. The overall early (30-day) mortality was 7.9%. The early survival was 75% in separate valve-graft procedure and 99.2% in composite valve-graft procedure. Late coronary dehiscence did not occur in the patients with Bentall technique in which the reattachments of coronary ostia were performed in 2 layers, but occurred in 50% of patients with the coronary anastomoses in 1 layer. Aortic valve regurgitation relapsed in 2 of the 5 patients with valve sparing procedure. Event free rate for the patients with composite valve-graft using button technique was 81.1% at 10 years. There were 14 late deaths; dissection or rupture of the residual aorta, composite graft endocarditis and cardiac failure were the principle causes of late deaths. In conclusion, Marfan patients with cardiovascular diseases can undergo surgical treatment with a low operative risk and low morbidity. Although late endocarditis remains a serious problem, we believe that Marfan syndrome is a contraindication for valve sparing procedure. Because of the potential for late dissection or aneurysm in other areas of the aorta, patients with Marfan syndrome should have serial computed tomographic scans indefinitely.

Adolescent↗
PubMed2002

Significance of distal fenestration in graft replacement for chronic aortic dissection.

It is recently controversial whether distal fenestration is necessary in graft replacement for chronic aortic dissection. Several groups started to try the exclusion of intimal entry by the insertion of a stent-graft as a treatment for chronic aortic dissection, while conventional surgical techniques consisted of graft replacement with distal anastomosis to both the true and false channels. It should be kept in mind that the resultant occlusion of the false lumen after obliteration of the false channel could promote spinal cord ischemia. We report a patient with delayed paraplegia after graft replacement without distal fenestration for chronic type B aortic dissection. It is possible that not all cases of chronic aortic dissection are good for stent-grafting.

Aortic Dissection↗
PubMed2002

[Antegrade selective cerebral perfusion for extended total arch replacement using separated graft technique; reassessment from the type of aneurysms and dissections].

One hundred eighty two patients with thoracic aortic aneurysms or dissections who required total arch replacement (TAR) were operated on with separated graft technique and selective cerebral perfusion (SCP) between 1991 and 2000. These patients were divided into 4 groups according to the pathology as follows: group 1; acute type A dissection, group 2; chronic type A dissection, group 3; distal arch aneurysm and group 4; proximal arch aneurysm. For SCP, both the innominate artery and the left common carotid artery were cannulated when the patient was cooled to a rectal temperature of 22 degrees C. Hospital mortalities were 27% in group 1, 14% in group 2, 19% in group 3, and 8% in group 4. Independent predictors of hospital mortality were shock, visceral, and leg ischemia in group 1, and circulatory arrest time of the lower half body to be more than 1 hour and cardiopulmonary bypass time to be more than 5 hours in group 3. Permanent neurological complication occurred in 3% in group 1 and 8% in group 3. Hospital mortality was affected by the type of aneurysms and dissections. It is necessary to give careful consideration to the indication of TAR with SCP, especially in acute type A dissection and distal arch aneurysm.

Aged↗
PubMed2001

Gene structure and transcriptional regulation of human Gal beta1,4(3) GlcNAc alpha2,3-sialyltransferase VI (hST3Gal VI) gene in prostate cancer cell line.

We describe transcriptional regulation of the human Gal beta1,4(3) GlcNAc alpha2,3-sialyltransferase VI (hST3Gal VI) gene. The 5'-RACE results indicated that two mRNA forms differ only in the 5'-untranslated region (types 1 and 2). The genomic structure shows that the transcriptional regulation of type 1 and type 2 mRNA depends on the P1 and P2 promoters, respectively. Northern blots of RNA derived from various human tissues showed that the expression level of type 2 mRNA is higher than that of type 1 in the prostate. To elucidate the molecular basis of hST3Gal VI gene expression, we isolated and functionally characterized the genomic region containing the P1 and P2 promoters of hST3Gal VI. The activity of the P2 promoter is much higher than that of the P1 promoter in the prostate adenocarcinoma cell line PC-3. The results suggested that the hST3Gal VI gene is expressed specifically by alternative promoter utilization and is regulated in a tissue-restricted fashion at the level of transcription.

Adenocarcinoma↗
PubMed2001

Primary culture system of adrenocortical cells from dogs to evaluate direct effects of chemicals on steroidogenesis.

The present study was conducted to confirm the usefulness of a primary culture system of adrenocortical cells from dogs for detecting the direct effects of the chemicals on adrenal cortex. Corticosteroid levels in the culture supernatant were measured using high-performance liquid chromatography (HPLC) following 24-h incubation with the chemicals. Ketoconazole, miconazole, metyrapone, aminoglutethimide, and 1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2-dichloroethane (o,p-DDD), which were known to inhibit cortisol production were evaluated in this system. Both viable cells and corticosteroid levels were decreased by o,p-DDD treatment. Other chemicals showed various inhibition patterns of corticosteroid levels as follows without affecting cell viability. Ketoconazole decreased total corticosteroids level by mainly due to the decreases in cortisol and 11-deoxycortisol levels. Miconazole decreased cortisol and 11-deoxycortisol levels, however, slightly increased corticosterone level. Metyrapone decreased cortisol and corticosterone levels as 11-deoxycortisol and 11-deoxycorticosterone levels were increased. Aminoglutethimide decreased total corticosteroids level by mainly decreasing cortisol, corticosterone and 11-deoxycortisol levels. These results suggested that determination of the pattern of corticosteroid levels by HPLC in this system well reflected the mode of their action on steroidogenesis. Thus, we conclude this simple system was useful to determine the direct effects of chemicals on steroidogenesis in the adrenal cortex.

Adrenal Cortex↗
PubMed2001

GPHN, a novel partner gene fused to MLL in a leukemia with t(11;14)(q23;q24).

We report a novel MLL-associated chromosome translocation t(11;14)(q23;q24) in a child who showed signs of acute undifferentiated leukemia 3 years after intensive chemotherapy that included the topoisomerase-II inhibitor VP 16. Screening of a cDNA library of the patient's leukemic cells showed a novel fusion transcript between MLL and the Gephyrin (GPHN) gene on 14q24. The resulting MLL-GPHN fusion gene encodes MLL AT hook motifs and a DNA methyltransferase homology domain fused to the C-terminal half of Gephyrin, including a presumed tubulin binding site and a domain homologous to the Escherichia coli molybdenum cofactor biosynthesis protein MoeA. Genomic breakpoint analysis showed potential in vitro topoisomerase-II DNA-binding sites spanning the breakpoints in both MLL and GPHN but no flanking sequences that might mediate homologous recombination. This suggests that MLL-GPHN may have been generated by VP 16/topoisomerase-II-induced DNA double-strand breaks, followed by error-prone DNA repair via non-homologous end joining. Gephyrin was originally identified as a submembraneous scaffold protein that anchors and immobilizes postsynaptic membrane neurotransmitter receptors to underlying cytoskeletal elements. It also is reported to bind to phosphatidylinositol 3,4,5-triphosphate binding proteins involved in actin dynamics and downstream signaling and interacts with ATM-related family member RAFT1. Gephyrin domains in the chimeric protein therefore could contribute novel signal sequences or might modify MLL activity by oligomerization or intracellular redistribution.

Amino Acid Sequence↗
PubMed2001

Simultaneous cardiac operations with pulmonary resection for lung carcinoma.

OBJECTIVES: A procedure remains to be established for managing patients with both cardiac and pulmonary diseases requiring surgical interventions. We review our experience with 6 patients having cardiac disease and lung cancer surgically treated simultaneously to determine whether simultaneous surgery is safe and effective. METHODS: Subjects were 6 men with a mean age of 64 +/- 10 years undergoing cardiac surgery combined with pulmonary lobectomy from January 1986 through June 2000. Cardiac procedures consisted of coronary artery bypass in 3, coronary artery bypass plus left ventricular aneurysm repair, aortic valve replacement, and minimally invasive direct coronary artery bypass surgery in 1 patient each. All underwent lobectomy. RESULTS: No early deaths occurred. Bleeding complications occurred in 2 patients and lymph node dissection was incomplete in 3. Two died of carcinoma-related events, 1 at 28 and the other at 84 months after surgery. One died suddenly from a cardiac-related event 42 months after surgery. Only 1 patient is currently alive and disease-free at 104 months after surgery. CONCLUSION: Simultaneous surgery can be conducted with acceptable mortality. The occurrence of bleeding complications and incomplete lymph node dissection, however, indicates combined procedures only in patients requiring simultaneous surgery due to their disease or unable to tolerate a second operation.

Aged↗
PubMed2001

Traction-type heart stabilizer for off-pump coronary bypass grafting.

We designed a stabilizer to assist us in performing coronary artery bypass grafting on the beating heart. The stabilizer consists of a U-shaped holed platform, an articulating arm, and a clamp for attachment to an ordinary sternal retractor. The target coronary artery is dissected, then two elastic sutures, 15-20mm apart, are wrapped around it, proximal and distal to the anastomotic site. These sutures for traction are passed through holes in the U-shaped platform and tied. This traction immobilizes the target area of the coronary artery. The stabilizer described herein provides good exposure and steady immobilization to enable anastmosis to be more easily performed in the beating heart.

Anastomosis, Surgical↗
PubMed2001

Surgical treatment of thoracoabdominal aortic aneurysm after repairs of descending thoracic or infrarenal abdominal aortic aneurysm.

OBJECTIVE: The outcome of thoracoabdominal aortic aneurysm repair after operations for descending thoracic or infrarenal abdominal aortic aneurysm was investigated. METHODS: Between May 1982 and July 2000, 102 patients underwent thoracoabdominal aortic aneurysm repair. Of these patients, 36 had previously undergone operations for descending thoracic or abdominal aortic aneurysm. To evaluate the influence of previous descending thoracic or infrarenal abdominal aortic aneurysm repair on the results of TAAA replacement, patients were divided into two groups: one group of patients who had previously undergone descending thoracic or infrarenal abdominal aortic aneurysm repair (group I, n=36) and one group of patients who had not previously undergone descending thoracic or infrarenal abdominal aortic aneurysm repair (group II, n=66). RESULTS: Patients with previous descending thoracic or infrarenal abdominal aortic aneurysm repair had more chronic dissection and extensive thoracoabdominal aortic aneurysm. The distal aortic perfusion time and total aortic clamp time were both longer in group I. The total selective visceral and renal perfusion time and operation time did not differ significantly between the two groups. In 30-day mortality rates were 5.5% in group I and 13% in group II. Major postoperative complications included paraplegia in 14% of patients in group I and 3.1% in group II, renal failure requiring hemodialysis in 22% of patients in group I and 19% of patients in group II, respiratory failure in 36% of patients in group I and 30% of patients in group II, postoperative hemorrhage in 11% of patients in group I and 16% of patients in group II. CONCLUSION: The presence of a previous descending thoracic or infrarenal abdominal aortic aneurysm did not adversely affect the outcome of thoracoabdominal aortic aneurysm repair.

Adult↗
PubMed2001

Tricuspid valve surgery for functional tricuspid valve regurgitation associated with left-sided valvular disease.

OBJECTIVES: We have reviewed 260 patients who underwent initial tricuspid valve surgery for functional tricuspid valve regurgitation (TR) and analyzed independent predictors for early and late unfavorable results. MATERIALS AND METHODS: Between 1981 and 1998, 260 tricuspid valve operations were performed for functional TR. There were 94 males and 166 females with a mean age of 55 years. The tricuspid valve surgery procedures consisted of De Vega tricuspid annuloplasty in 240 patients, ring annuloplasty in four patients, and tricuspid valve replacement in 16 patients. The mean duration of follow-up was 7.8 years. RESULTS: Hospital mortality was 8.9% (23 patients). Late deaths occurred in 34 patients including cardiac-related late deaths in 26 patients. The survival rates were 83+/-2% at 5 years and 78+/-3% at 10 years. Late tricuspid valve reoperation was performed on 13 patients due to residual or recurrent TR in 12 patients and thrombosed tricuspid bileaflet mechanical valve in one patient. The tricuspid valve reoperation-free survival rate was 90+/-2% at 5 years and 84+/-3% at 10 years. The only predictor of hospital mortality was preoperative highly elevated right atrial pressure (P=0.01). Variables predictive of cardiac-related late death were preoperative New York Heart Association (NYHA) class IV (P=0.01) and poor left ventricular ejection fraction (LVEF) (P=0.02). Residual TR of more than grade 2+ early after tricuspid annuloplasty was a significant risk factor for late tricuspid valve reoperation (P=0.01). Preoperative TR of grade 4+ was predictive of early residual TR (P=0.04). CONCLUSIONS: Tricuspid valve surgery for functional TR can be performed with acceptable levels of early mortality. Cardiac-related late mortality after tricuspid surgery may be improved by earlier surgical treatment before NYHA class IV or deterioration of LVEF occurs. To prevent late tricuspid reoperation, it is important not to leave residual TR of grade 2+ or more after tricuspid annuloplasty.

Aged↗