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T Nojima

Publications and source records attributed to T Nojima.

At least 91 records · Page 5Linked to original sources
PubMed1994

Optimal perfusion pressure for experimental retrograde cerebral perfusion.

We evaluated cerebral metabolism during retrograde cerebral perfusion (RCP) and circulatory arrest during profound hypothermia, and also investigated the effects of perfusion pressure on RCP. Twenty-four adult mongrel dogs were placed on cardiopulmonary bypass and cooled to a nasopharyngeal temperature of 20 degrees C. At this temperature, hypothermic circulatory arrest (HCA; n = 6), and RCP with a perfusion pressure of 10 mmHg (RCP10; n = 6), 20 mmHg (RCP20; n = 6), and 30 mmHg (RCP30; n = 6) were carried out for 60 minutes. RCP was performed with oxygenated blood via the bilateral maxillary veins, and the retrograde flow rate was regulated to maintain a mean perfusion pressure of 10, 20, or 30 mmHg in the external jugular vein. At 60 minutes of RCP, we measured nasopharyngeal temperature; regional cerebral blood flow (rCBF); cerebral oxygen consumption, carbon dioxide excretion, and excess lactate; cerebral tissue adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and energy charge; and cerebral tissue water content. In the RCP10 group, there was excess cerebral lactate, and ATP and energy charge were low. In the RCP30 group, the water content of cerebral tissue was significantly higher than in other groups. In the RCP20 group, temperature was maintained in a narrow range, oxygen consumption and carbon dioxide excretion could be observed, there was no excess lactate, and ATP and energy charge were significantly higher than in the HCA group. In conclusion, RCP can provide adequate metabolic support for the brain during circulatory arrest, and a perfusion pressure of 20 mmHg is most appropriate for RCP.

Animals↗
PubMed1994

[Detection of autoantibodies in sera from patients with rheumatoid arthritis].

Although Rheumatoid Arthritis (RA) is categorized in the systemic autoimmune diseases, specific autoantibodies in RA have been reported to be rare. We have investigated autoantibodies found in sera from patients with RA and examined their clinical significance. Immunoprecipitation techniques using 32P-labeled or 35S-labeled HeLa cell extracts and immunoblotting were utilized to detect autoantibodies in sera from 42 patients with RA and 58 patients with other connective tissue diseases as controls. Certain autoantibodies were detected in 33 of 42 patients (79%) with RA by any of the assay systems mentioned above. Anti-SSA/Ro, anti-SSB/La, anti-7-2RNP, and anti-Sm antibodies were found in 13 (29%), 3 (7%), 4 (10%), and 1 (2%) patients with RA, respectively. All 3 patients with anti-SSB/La and 9 with anti-SSA/Ro revealed Sjögren's syndrome besides RA. However, all 4 patients with anti-7-2RNP and one patient with anti-Sm showed no evidence of scleroderma nor SLE. Besides of these known autoantibodies, we have also detected 4 new antibodies which reacted with a 60kD protein in 15 (36%), 45kD in 10 (24%), 75kD in 8 (19%), 180kD in 4 patients (10%) with RA. These autoantibodies were not found in other connective tissue diseases except one of SLE for anti-60kD and one of dermatomyositis for anti-75kD, and therefore appeared to be specific for RA patients. Anti-45kD antibodies were associated with low prevalence of anti-nuclear antibodies, and anti-180kD antibodies were associated with lymphadenopathy and Sjögren's syndrome. Thus, it was demonstrated that patients with RA develop a variety of autoantibodies as well as those with other connective tissue diseases.

Arthritis, Rheumatoid↗
PubMed1994

A clinical study on the effects of pulsatile cardiopulmonary bypass on the blood endotoxin levels.

Levels of endogenous endotoxins have been reported to increase after cardiopulmonary bypass. Endotoxin levels have also been implicated in multiple organ failure and may contribute to the immunocompromised state seen after bypass. We evaluated the effects of pulsatile cardiopulmonary bypass circulation on endogenous endotoxin levels. The study population consisted of 15 consecutive adult patients who underwent cardiac operations with cardiopulmonary bypass. Pulsatile flow was used during aortic crossclamping in eight patients (group I) and nonpulsatile flow was used in the remaining seven patients (group II). Changes in blood endotoxin levels were monitored during aortic crossclamping, after release of the clamp, and after weaning from bypass. The blood endotoxin level at each stage was expressed as a percentage of the level at the beginning of bypass. Group I patients a significantly lower blood endotoxin percentage than group II (from 20 to 120 minutes after the initiation of aortic crossclamping). In group I, the blood endotoxin percentage was nearly constant during aortic crossclamping. After release of aortic crossclamping, group I also had a lower blood endotoxin percentage than group II. Endogenous endotoxin levels appear to increase in the presence of intestinal congestion and ischemia. Improvement in intestinal circulation by pulsatile cardiopulmonary bypass may prevent increases in endogenous endotoxin levels by reducing these factors.

Adult↗
PubMed1994

[Experimental study of optimal perfusion pressure during retrograde cerebral perfusion].

The effects of retrograde perfusion pressure on the brain was experimentally investigated during profound hypothermic circulatory arrest. Fifteen adult mongrel dogs were placed cardiopulmonary bypass and induced profound hypothermia of 20 degrees C at nasopharyngeal temperature. Retrograde cerebral perfusion (RCP) with perfusion pressure of 10 mmHg (RCP10; n = 5), 20 mmHg (RCP20; n = 5), 30 mmHg (RCP30; n = 5) underwent for 60 minutes. The oxygenated blood was infused via the bilateral maxillary veins, and the flow rate was kept to maintain a desired pressure in the external jugular vein for each group. Regional cerebral blood flow (rCBF), excess lactate, cerebrospinal fluid pressure (CSFP), adenosine triphosphate (ATP) concentration of cerebral tissue, and water content of cerebral tissue were measured. In the RCP10 group, cerebral excess lactate was positive and ATP concentration was low. In the RCP30 group, the water content of cerebral tissue was significantly higher than those in the other groups. In the RCP20 group, the excess lactate was maintained in a negative range, and ATP concentration was significantly higher than in the RCP10 group. In conclusion, RCP may provide metabolically adequate support for the brain and a perfusion pressure of 20 mmHg was appropriate for RCP in dogs.

Animals↗
PubMed1994

The effect of pulsatile perfusion on cerebral blood flow during profound hypothermia with total circulatory arrest.

In 39 mongrel dogs, regional cerebral blood flow was measured during pulsatile and nonpulsatile deep hypothermic cardiopulmonary bypass with total circulatory arrest. Total circulatory arrest was performed at 20 degrees C cerebral temperature for 40 minutes in 15 dogs, 60 minutes in 12 dogs, and 80 minutes in 12 dogs. Cerebral blood flow in both groups decreased as cerebral temperature fell and there was no significant difference in cerebral blood flow between the two groups during the cooling period. After circulatory arrest for 40 minutes, as cerebral temperature increased to 35 degrees C, cerebral blood flow in both groups recovered to values as high as the respective initial values, which were measured just after the beginning of cardiopulmonary bypass for cooling (102.5% +/- 10.2% in the pulsatile group and 97.2% +/- 12.6% in the nonpulsatile group). After circulatory arrest for 60 minutes, cerebral blood flow in the pulsatile group increased to 141.8% +/- 16.1% of its initial value when the cerebral temperature became 35 degrees C, but it remained significantly lower (64.5% +/- 9.2%) in the nonpulsatile group (p < 0.01). After circulatory arrest for 80 minutes, cerebral blood flow in both groups remained lower than the respective initial values. These results suggest that pulsatile perfusion maintains cerebral blood flow even during profound hypothermia and that it may protect the brain from ischemic and hypoxic damage caused by profound hypothermia and total circulatory arrest in cardiac operations.

Animals↗
PubMed1994

[Experimental studies of pulsatile retrograde cerebral perfusion].

This study was investigated for the effects of pulsatile flow on retrograde cerebral perfusion under profound hypothermic circulatory arrest. Fifteen adult mongrel dogs were placed cardiopulmonary bypass and induced profound hypothermia of 20 degrees C at nasopharyngeal temperature. Five dogs were performed non-pulsatile retrograde cerebral perfusion (NP-RCP) and 5 were pulsatile retrograde cerebral perfusion (P-RCP) for 60 minutes each group. The rest of 5 dogs were performed hypothermic circulatory arrest (HCA) without any circulatory assist. Retrograde cerebral perfusion flow rate was regulated to maintain an external jugular vein pressure of 20 mmHg by infusing oxygenated blood by way of bilateral maxillary vein. Regional cerebral blood flow (rCBF), cerebrospinal fluid pressure (CSFP), adenosine triphosphate (ATP) concentration of cerebral tissue, and water content of cerebral tissue were measured. The rCBF were no statistical difference between the two groups. CSFP and ATP concentration in both of NP-RCP and P-RCP were significantly higher than those of HCA. Water content of cerebral tissue in P-RCP were significantly lower than those of NP-RCP. We concluded that retrograde cerebral perfusion for 60 minutes protects the brain as the assistances of circulatory arrest and retrograde cerebral perfusion with pulsatile flow has the possibility to control brain edema as compared with non-pulsatile flow in dogs.

Adenosine Triphosphate↗
PubMed1993

[A clinical and pathological study of non-Hodgkin's lymphoma of the nasal cavity and paranasal sinuses].

We studied 30 patients with early stage malignant lymphomas involving the nasal cavity and/or paranasal sinus who were treated between 1972 to 1991 in Hokkaido University Hospital. The mean age of the patients was 60.6 yr, and the male-to-female ratio was 2.6. The predominant histologic type was diffuse large cell type (n = 23). Treatment policy differed depending on time: radiotherapy (RT) alone between 1972 and 1980 (n = 15), RT followed by modified CVP or CHOP between 1981 and 1988 (n = 10) and BACOP followed by RT between 1989 and 1991 (n = 5). Overall five-year survival was 53%. Better survival was observed in patients with B-cell type (72%), smaller mass (tumor limited to the unilateral nasal cavity or paranasal sinus) (76%), and patients who were treated with combination chemotherapy (BACOP) followed by RT (100%). Eleven patients experienced recurrence. Four of nine local recurrences were in patients with T-cell lymphoma. CNS relapse was observed in three patients with T-cell lymphoma. We conclude that T-cell lymphoma arising at the nasal cavity and/or paranasal sinus needs careful follow-up for its high frequency of local and CNS relapse. More intensive treatment such as prophylactic whole brain RT, intrathecal administration of MTX or third generation chemotherapy (e.g. MACOP-B) might improve survival in these patients.

Adolescent↗
PubMed1993

Pleomorphic carcinoma of the pancreas with osteoclast-like giant cells.

We studied two cases of pleomorphic carcinoma of the pancreas with osteoclast-like giant cells. The cut surface of both tumors was firm and whitish-tan in color, with extensive hemorrhage and necrosis. Microscopically, these tumors were composed mainly of pleomorphic mononuclear cells and numerous bizarre giant cells, with a spindle-cell sarcomatoid appearance and adenocarcinomatous elements exhibiting varying degrees of differentiation. Multinucleated giant cells resembling osteoclasts were frequently located around sites of necrotic hemorrhage. Immunohistochemically, most tumor cells of sarcomatous areas and some anaplastic giant cells were positive for vimentin and cytokeratin. Both carcinoembryonic antigen and CA 19-9 were detected in tumor cells in one case, forming ducts or glands. These findings suggest that the tumors in these two cases originated from pancreatic-duct cells with mesenchymal differentiation. In contrast, osteoclast-like giant cells in both cases showed strong immunoreactivity with vimentin and with KP1 and PG-M1 (CD68), which are monoclonal antibodies that react with a histiocyte-macrophage-associated antigen; however, there was no reaction with any epithelial markers. Thus, osteoclast-like giant cells are not epithelial in nature, suggesting that their origin of histiocyte-macrophage lineage is possibly induced as a paraneoplastic product.

Aged↗
PubMed1993

Surgical treatment of the Wolff-Parkinson-White syndrome in children.

From 1986 to 1989, seven children ranging in age from 5 months to 16 years underwent surgical treatment for the Wolff-Parkinson-White syndrome at the Shiga University of Medical Science. None of the patients had any other associated congenital heart disease. There was a right free wall accessory pathway in four patients and a left free wall accessory pathway in three. Surgical ablation of these accessory pathways was performed on eight occasions, using the endocardial approach three times and the epicardial approach five. All the children are alive and none has since had episodes of tachycardia. Only one patient had a recurrent delta wave, which was noted 18 months after the operation. Surgical ablation of the accessory pathway for the Wolff-Parkinson-White syndrome can be performed safely, even in infants and children; it is concluded that this useful procedure is capable of improving a patient's quality of life.

Adolescent↗
PubMed1993

Vacuolated meningioma with secretory features: a case report.

We report a case of meningioma with secretory features in a 47-year-old woman. The left frontal tumor mass had already eroded the overlying bone at the time of presentation. When respected, the mass showed a gelatinous appearance. Histologically, marked vacuolar change was seen in the stroma. Whorls, psammoma bodies, and pavement arrangement of nuclei were also noted. Periodic acid-Schiff stain revealed cytoplasmic granules, which were digested with diastase. Alcian blue diffusely stained the cytoplasm of the tumor cells. Electron microscopy showed numerous small vacuoles and cored vesicles in the cytoplasm. Glycogen granules were poorly observed. These features indicate the mild secretory nature of this vacuolated meningioma.

Female↗
PubMed1993

Acute extensive necrosis of the visceral organs after repair of a ruptured thoracic aortic aneurysm.

A 47-year-old woman was admitted to our hospital for repair of a ruptured thoracic aortic aneurysm. Her post-operative course was uneventful, but she had persistent complaints of anorexia and general fatigue that failed to improve. Thirty-one days after surgery, she complained of severe abdominal pain. Abdominal computed tomography (CT) and X-ray revealed extensive necrosis of the visceral organs. She underwent emergency abdominal exploration and was found to have necrosis of the liver, gallbladder, stomach, entire small bowel and colon. The extensive necrosis made resection of the involved organs unfeasible. The patient died one day after exploratory laparotomy.

Acute Disease↗
PubMed1993

Cerebral metabolism and effects of pulsatile flow during retrograde cerebral perfusion.

We evaluated cerebral metabolism during retrograde cerebral perfusion (RCP) and circulatory arrest under profound hypothermia, and also investigated the effect of pulsatile flow on RCP. Eighteen adult mongrel dogs were placed on cardiopulmonary bypass and were cooled to a nasopharyngeal temperature of 20 degrees C. At this temperature, hypothermic circulatory arrest (HCA; n = 6), non-pulsatile RCP (NP-RCP; n = 6), and pulsatile RCP (P-RCP; n = 6) were performed for 60 minutes. Retrograde cerebral perfusion was performed via the bilateral internal maxillary veins, and retrograde flow rate was regulated to maintain a mean perfusion pressure of 20 mmHg in the external jugular vein. During RCP, the temperature was maintained in a narrow range, oxygen consumption and carbon dioxide excretion could be observed, the excess lactate was maintained at a negative value, and cerebral tissue ATP concentration was significantly higher than in the HCA group. The cerebral tissue water content was significantly lower in the P-RCP group than in the NP-RCP group. These findings suggest that hypothermia of the central nervous system, the supply of oxygen, the excretion of metabolites, aerobic metabolism, and the cerebral ATP level were maintained by RCP. In conclusion, RCP may possibly provide adequate metabolic support for the brain during total circulatory arrest, and pulsatile flow appears to reduce cerebral edema when compared with non-pulsatile flow in dogs.

Adenosine Triphosphate↗
PubMed1993

[Experimental studies on retrograde cerebral perfusion: efficacy of clamping of the venous blood flow through IVC cannula].

Retrograde cerebral perfusion (RCP) is used to prolong the safe period of circulatory arrest under profound hypothermia. However, this technique now varies in some maneuvers at different institutions. This study investigated the effects on cerebral metabolism of clamping blood flow through the IVC cannula during RCP using fourteen adult mongrel dogs. During circulatory arrest, RCP by way of the bilateral internal maxillary vein was performed. In seven dogs, blood flow was drained through IVC cannula (IVC-drained group) and in the other seven dogs, the blood flow was clamped during RCP (IVC-clamped group). During RCP, the percent of returned blood volume, oxygen consumption, exudation of carbon-dioxide, and oxygen saturation of the returned blood were significantly higher in the IVC-clamped group than in the IVC-drained group, and the concentration of serum CK-BB in the IVC-clamp group was significantly lower than in the IVC-drained group. However, there was no statistical difference between the two groups concerning the regional cerebral blood flow or water content of the cerebral tissue. Concerning about these results, a part of perfused blood passed through not only the extra cranial veno-venous connection but also the intra cranial veno-capillary-venous connection. We concluded that clamping of the venous blood flow through the IVC cannula during RCP is a more protective procedure for cerebral tissue.

Animals↗
PubMed1993

A computer simulation of the plasma leakage through a vascular prosthesis made of expanded polytetrafluoroethylene.

We explored the blood-retaining mechanism of a vascular prosthesis made of expanded polytetrafluoroethylene through analysis of its structure and physicochemical properties. Plasma leakage through this vascular prosthesis was simulated by computer to explore its etiology. These examinations disclosed that leakage is dependent upon the inner pressure and the density of fibers. In other words, the study revealed that the mean distance between fibers constituting the wall of the expanded polytetrafluoroethylene vascular prosthesis is increased by tension (that is, inner pressure), resulting in an increased probability of leakage. It was additionally found that a thin membrane is formed on the polytetrafluoroethylene surface if blood in contact with the surface is dried. This membrane was found to reduce the water-repelling property of polytetrafluoroethylene and to make it impossible to preserve the inter-fiber liquid surface, thus causing leakage through the expanded polytetrafluoroethylene vascular prosthesis.

Blood Vessel Prosthesis↗
PubMed1993

[Removal of infected transvenous electrodes requiring cardiopulmonary bypass or extraction sheath].

Infection of four transvenous pacemaker electrodes were experienced in three patients and removed them using different techniques. The first patient had two infected electrodes. One was removed by direct traction and the other required cardiopulmonary bypass for its removal. In the second patient, one electrode was removed using a new extraction system called 'Lead Removal Kit' without thoracotomy. In the third patient, the kit was used during cardiopulmonary bypass. All these patients survived and none had recurrent infection. Our experiences proved that this Lead Removal Kit can minimize the risks for the removal of the infected pacemaker electrodes.

Aged↗