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M Hisanaga

Publications and source records attributed to M Hisanaga.

At least 55 records · Page 3Linked to original sources

Patterns of donor-type microchimerism after heart transplantation.

Allogeneic microchimerism of donor-type has been demonstrated in stable patients in the long-term after organ transplantation. We have analysed microchimerism in skin and blood of 47 heart-transplanted patients after transplantation with polymerase-chain-reaction amplification specific for donor HLA-DRB1. Microchimerism was detectable in 50% of the patients in the first 6 months, in 100% between 6 months and 2 years, and in 58% in the third postoperative year or later. The state of chimerism was not related to acute or chronic rejections. Patterns of microchimerism after heart transplantation may be dynamic, but any association with clinical and immunological variables remains to be elucidated.

Gene Amplification↗

Protective effect of the calcium channel blocker diltiazem on hepatic function following warm ischemia.

The purpose of this study was to investigate the protective effect of a calcium channel blocker diltiazem (DTZ) on hepatic ischemic injury using a canine model. Hepatic ischemia was induced by temporary clamping of hepatic afferent blood vessels for 60 min with establishment of a portojugular bypass. The administration of DTZ at a dose of 70 micrograms/kg bolus i.v. injection before hepatic ischemia and thereafter via the portal vein at a dose of 10 micrograms/kg/min well restored the hepatic blood flow (HBF, 92 +/- 5%; P < 0.01) and arterial ketone body ratio (AKBR, 1.15 +/- 0.16; P < 0.01) 1 hr after interruption compared with untreated controls (HBF, 61 +/- 7%; AKBR, 0.53 +/- 0.09). In addition, the increase of plasma lactate level and the decrease of mean arterial pressure were significantly suppressed after ischemia (P < 0.05). We concluded that DTZ has a protective effect on ischemia-induced hepatic damage and might be useful in the prevention of primary graft failure caused by warm ischemia in liver transplantation.

Animals↗

A solid and papillary (solid-cystic) tumor of the pancreas occurring in a 36-year-old man: report of a case.

A case of a solid and papillary (solid-cystic) tumor of the pancreas occurring in a 36-year-old man is herein reported. This patient was admitted with left hypochondrial pain and diagnostic imaging detected a large tumor consisting of both solid and cystic components in the tail of the pancreas. A distal pancreatectomy with splenectomy was performed. The resected tumor was diagnosed as a solid and papillary tumor of the pancreas by pathological examination. Detailed immunohistochemical studies showed that the tumor consisted of cells both exocrine and endocrine in character. Thus, this case appears interesting from the point of cellular differentiation in solid and papillary tumors, since they are generally considered to have an acinar cell origin.

Adult↗

Cytoimmunologic monitoring using DNA analysis in canine liver transplantation.

In this experiment, we evaluated the significance of flow cytometric DNA content measurement of circulating blood mononuclear cells in early detection of canine hepatic allograft rejection. In nonimmunosuppressed controls, the SG2M% of blood mononuclear cells significantly increased on days 5-6 after liver transplantation compared with the pretransplant values (P < 0.01). At the time of SG2M% elevation, microscopic examination of the graft revealed acute mild rejection. These changes in SG2M% and histological findings were observed one or two days earlier than biochemical changes indicative of liver injury. On the other hand, nonrejected cases under sufficient immunosuppression with cyclosporine or FK506 maintained low levels of SG2M% in comparison with the pretransplant values (P < 0.05). The rejecting cases under insufficient immunosuppression showed significantly elevated SG2M% (P < 0.05), and successful steroid pulse therapy provided to the recipients immediate normalization of SG2M% with histological restoration. Moreover, other complications such as pulmonary infection, peritonitis, and marasmus--rather than the rejection reaction--did not influence on SG2M%. These results led us to believe that flow cytometric DNA content measurement of blood mononuclear cells provides relevant and early information with respect to ongoing canine hepatic allograft rejection. The diagnostic value for differentiation between hepatic allograft rejection and infection of the transplant by hepatitic viruses needs further evaluation.

Animals↗

[Chronic encapsulated intracerebral hematoma associated with cavernous angioma: case report and review of the literature].

We reported a case of chronic encapsulated intracerebral hematoma associated with cavernous angioma. A 71-year old female was admitted with a history of frontal headaches at intervals of about 3 months for the last one year. Plain CT scan showed a round mass of heterogeneous high density in the left medial frontal lobe. The outer surface of the mass was enhanced with contrast material. MRI demonstrated the mass as a high signal intensity on T1-weighted image and low intensity with laminated structure on T2-weighted image. MR angiogram depicted the mass as a mottled high signal intensity. The left internal carotid artery angiogram revealed no abnormal shadows and vessels. These findings suggested some form of a thrombus although its underlying pathogenesis was unclear. On January 20, 1992, a bifrontal craniotomy was performed. A whitish well-demarcated mass was seen in the left cingulate gyrus through a small corticotomy. We could not identify any branches feeding the mass. The cross-section of the mass disclosed a uniform thrombus encapsulated by a thick wall. Histological studies of the wall confirmed a cavernous angioma within the outer collagenous layers. Chronic encapsulated hematoma, which was first reported by Hirsh in 1981, has represented a separate entity and 25 such cases have been documented in the literature. These reports suggested that the compression and/or destruction of the surrounding tissue caused by the hemorrhage would mask the existence of the cavernous angioma or vascular malformation. If an encapsulated hematoma were encountered during an operation, surgeons should pay attention not to overlook the residual capsule encompassing the cavernous angioma or vascular malformation.

Adolescent↗

[Experimental study of multi-visceral transplantation in dogs].

The purpose of the present study was to examine the technical, functional and immunologic aspects in the multivisceral transplantation using canine model. After removal of upper abdominal organs en bloc, the composite graft including the liver, pancreas, spleen and duodenum was orthotopically transplanted in 35 dogs. Ten recipients survived more than 3 days, and 6 more than 6 days. Cause of early death was massive lymphatic leakage, and late death was due to acute rejection or other complications. As technical considerations, perfusion of the graft should be only via aorta to prevent pancreatic edema, and reperfusion should be at first with arterial blood flow to minimize the ischemic damage of the graft. Hepatic and pancrease-endocrine functions were recovered by 3 days, after grafting, and 2-3 days later pancreas-exocrine function was restored. Thereafter the hepatic function was progressively deteriorated again from 6 to 8th day, although the pancreatic function was well maintained until death. At autopsy this hepatic dysfunction was histologically confirmed to be caused by severe acute rejection. On the other hand, the pancreas and duodenum were morphologically almost normal. The results demonstrated the dissociation in functional recovery after grafting and extent of rejection reaction among each grafted organ in the multivisceral transplantation.

Animals↗

[DNA analysis of peripheral blood mononuclear cells for early detection of hepatic graft rejection].

We evaluated the significance of flow cytometric DNA content measurement of peripheral blood mononuclear cells for early detection of hepatic allograft rejection. A total of 15 orthotopic liver transplantation was performed using canine model. Animals were divided in two groups consisting of 5 dogs as untreated controls, and administered cyclosporine (n = 6) or FK506 (n = 4). Blood mononuclear cells DNA contents were analyzed by Propidium iodine method using FACScan. In untreated controls (n = 5), SG2M% of the mononuclear cells value significantly elevated on day 5 or 6 to 15.6 +/- 0.7% (mean +/- SE) compared to pretransplantation value (10.2 +/- 0.6%) (p < 0.01). At the time of SG2M% elevation, microscopic examination of the graft revealed acute mild rejection. These changes in SG2M% and histological finding were observed one or two days earlier than biochemical changes indicative of liver injury. On the other hand, non-rejected case under sufficient immunosuppression, SG2M% remained low levels (3.8 +/- 1.1%) in comparison with pretransplant values (8.8 +/- 0.6%) (p < 0.05). The rejecting cases under insufficient immunosuppression, SG2M% significantly elevated to 13.6 +/- 1.3% (p < 0.01). When steroid pulse therapy was successfully performed, it subsequently decreased to 5.6 +/- 0.7% (p < 0.01), and histological rejection reaction was disappeared. We concluded that serial measurement of DNA content of peripheral blood mononuclear cells may serve as an useful means for monitoring the immunological status of hepatic recipients.

Animals↗

Initial hepatic metabolic function in canine liver and pancreas cluster transplantation.

In this study, initial hepatic metabolic function was evaluated by determining the arterial ketone body ratio (AKBR) and plasma amino acid concentrations in an experimental orthotopic combined hepatopancreatic transplantation (OHPT), and comparing the same values in orthotopic liver transplantation (OLT). In OHPT, AKBR decreased in the anhepatic phase and recovered to the preoperative value just 1 h after reperfusion. On the other hand, in OLT, the recovery of AKBR took 3 h after reperfusion with a significant difference compared to OHPT (P less than 0.05). Plasma amino acid levels, especially alanine and total free plasma amino acids increased in the anhepatic phase and recovered within 1 h of reperfusion in OHPT. However, they did not recover until 3 h after reperfusion in OLT. This rapid recovery of hepatic metabolic function in OHPT should be attributed to the order of reperfusion in which the reconstruction of arterial blood flow precedes that of portal blood flow. This model is useful for assessing the best way by which the grafted liver can for assessing the best way by which the grafted liver can control the timing, order, rate, and volume of blood that should be released.

Amino Acids↗

Focal nodular hyperplasia of the liver.

We present herein two successfully treated cases of focal nodular hyperplasia (FNH) of the liver, a relatively rare disease. Case 1 was a 3 year old child in whom typical FNH developed in the left lateral segment of the liver, whereas Case 2 was a 22 year old man in whom characteristic findings were lacking on preoperative diagnostic imaging. Scintigraphy was not performed in either case, however, postoperative histological examination confirmed FNH. Thus, in patients with a hypervascular tumor and normal liver function, FNH should be strongly suspected and a series of scintigraphy proposed. Both cases showed a negative association with oral contraceptive intake but no other obvious etiology was suggested.

Adult↗

Neuroepithelial cyst of the lateral ventricle. Clinical features and treatment.

This report concerns eight patients with noncolloid neuroepithelial cyst of the lateral ventricle, including four surgical and four conservative cases. Of the surgical patients, two had headache, one had orbital pain, and one had seizures. In the conservative group there were no symptoms due to the cysts and no changes in computed tomography scan during follow-up for an average of 1.4 years. Magnetic resonance imaging was performed in five cases and showed a cyst with an intensity similar to cerebrospinal fluid, while a cyst membrane was also detected in three cases. Our findings suggest that (1) the majority of symptomatic neuroepithelial cysts in the lateral ventricle are located in the trigone; (2) the cause of symptoms suggestive of obstruction, such as headache, is an isolated ventricle that demonstrates dilatation of the inferior horn on computed tomography and magnetic resonance imaging; (3) the operative indication is obstructive symptoms; and (4) cyst-peritoneal shunt is an effective procedure.

Adult↗

Cortical and subcortical cavernous angioma: a comparison of patients with and without hemorrhage as the initial symptom.

Cavernous angioma is a benign vascular hamartoma with an obscure etiology. Clinical, radiological, and histological features of 24 cases of cortical and subcortical cavernous angiomas were analyzed to investigate the etiology. The lesions were classified as hemorrhaging (8 cases) or non-hemorrhaging (16 cases) according to the initial symptom. Age, sex, location, calcification and postcontrast enhancement by computed tomography (CT), tumor staining by angiography, and calcification and hemosiderin by histological examination were analyzed. Multivariate analysis showed that calcification by CT and histological examination correlated with non-hemorrhaging cases. Histological examination showed that calcification occurred inside and outside the blood vessels, within the vessel walls and in the adjacent brain tissue. Hemosiderin was also seen in most cases. These findings suggest that cavernous angiomas without hemorrhage have a poor circulation, resulting in minor recurrent bleeding and thrombosis, as well as calcification.

Adolescent↗

Diaphragma sellae meningioma associated only with signs of hypopituitarism--case report.

A rare diaphragma sellae meningioma presenting only with signs of hypopituitarism occurred in a 54-year-old male. Preoperative magnetic resonance (MR) imaging clearly demonstrated a small lesion in the supradiaphragmatic area immediately beneath the optic chiasm, displacing the pituitary stalk laterally. Intraoperatively, the tumor was confirmed to be attached only to the posterior leaf of the diaphragma sellae. Histological examination revealed a transitional type meningioma. Such a small meningioma may be associated only with hypopituitarism, as compression is confined to the pituitary stalk, not affecting the optic pathways. MR imaging can demonstrate the clinicopathological features of this small but significant tumor.

Humans↗