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Biomedical subjects

T Katsumata

Publications and source records attributed to T Katsumata.

At least 91 records · Page 5Linked to original sources

Ruptured left ventricular diverticulum in infancy.

Congenital diverticulum of the left ventricle is rare, and rupture of such a diverticulum is even more rare. We describe successful surgical repair of a ruptured left ventricular diverticulum in an 11-month-old infant.

Cardiac Tamponade↗

Aortic valve conservation in acute type A dissection.

BACKGROUND: We consider operative survival as the primary objective in acute type A dissection and believe that virtually all native aortic valves can be conserved. We sought to answer the question: "Does glue repair improve the long-term stability of proximal aortic repair?" METHODS: We retrospectively studied 64 patients with an acute type A dissection, an ascending aortic tear, and aortic regurgitation operated on by the same surgeon between 1988 and 1996. Three had Marfan's syndrome and 2 had a bicuspid valve. The valves in all patients without Marfan's syndrome were repaired with gelatin-resorcinol-formol glue. The valve and root were reinvestigated by echocardiography. Some patients underwent nuclear magnetic resonance imaging. RESULTS: There were four hospital (6%) and three late deaths. Aortic root reoperation was required in 2 of the 60 survivors (3.3%) and operation on the distal aorta in 2. Root reoperations were required within 3 years. The remaining proximal repairs remained stable. CONCLUSIONS: The native aortic valve can be conserved in most patients, and glue repair is durable. Simple root repair is associated with a low operative mortality.

Adult↗

Mechanical support in dilated cardiomyopathy: signs of early left ventricular recovery.

BACKGROUND: Recent reports have documented left ventricular recovery in patients with dilated cardiomyopathy off-loaded long term with a left ventricular assist device. We sought to document the natural history of left ventricular recovery. METHODS: We implanted the TCI left ventricular assist device without the intention to perform transplantation in 2 patients with dilated cardiomyopathy who had been rejected for transplantation. Both were in New York Heart Association functional class IV and had renal failure. One was a diabetic. We studied left ventricular function with detailed echocardiography at 4, 6, and 8 weeks postoperatively. RESULTS: With the left ventricular assist device turned off, we observed a progressive increase in myocardial contractility beginning as early as 4 weeks after implantation and improving progressively. Histologic examination showed resolution of myocytolysis in both patients. CONCLUSIONS: Left ventricular recovery begins earlier than was previously suspected. Mechanical bridge to myocardial recovery is a potential approach to therapy for such patients.

Cardiomyopathy, Dilated↗

The Jarvik 2000 Oxford system: increasing the scope of mechanical circulatory support.

METHODS: We developed a system for mechanical circulatory support based on the Jarvik 2000 intraventricular axial flow impeller pump (Jarvik Research, Inc., New York, N.Y.) and percutaneous electric power. The adult pump provides flow at a rate up to 10 L/min with an energy requirement of 7 to 10 watts. The device was implanted into the apex of the left ventricle through a left thoracotomy without cardiopulmonary bypass. A Dacron graft conveyed blood to the descending thoracic aorta. In patients, we will use a skull-mounted carbon pedestal to transmit fine electric wires through the scalp skin. Being highly vascular, the scalp skin is resistant to infection. RESULTS: We tested 16 adult systems and one pediatric system in 17 adult ewes weighing between 60 and 90 kg. Five died of perioperative complications. Twelve survived between 3 and 198 days (mean 44 days) with a functioning device. None of the sheep could receive adequate anticoagulation with warfarin (INR 1.0 to 1.5). Acute thrombotic occlusion occurred after a 3-hour power loss in one device (46 days) but was cleared with streptokinase. In a second animal with endocarditis, the pump inflow became occluded with vegetations. No other device-related problems or important hemolysis developed despite pump speeds between 10,000 and 18,000 rpm. Renal function remained normal in all animals. Autopsy studies showed no pannus ingrowth at the device inflow despite the restrictive left ventricular cavity size. No sign of thromboembolism could be detected in the brains or kidneys. CONCLUSION: Our findings indicate the Jarvik 2000 Oxford System to be a safe and effective circulatory assist device. Potential uses include permanent circulatory support, bridge to transplantation, or bridge to myocardial recovery in acute or chronic left ventricular failure.

Animals↗

Ki-67, p53, and Bcl-2 expression of serrated adenomas of the colon.

To investigate epithelial cell proliferation and oncoprotein expression of the serrated adenoma, a term that has been used synonymously with mixed hyperplastic and adenomatous polyp, immunohistochemical staining using polyclonal antibodies against Ki-67 and p53, and a Bcl-2 monoclonal antibody, was performed and the results compared with those in hyperplastic polyps and tubular adenomas. A total of 20 serrated adenomas all characterized by a serrated glandular pattern, contained immature goblet cells, upper crypt zone mitotic figures, and a few nucleoli within the epithelial cells. Twenty hyperplastic polyps and 20 tubular adenomas (all with low-grade dysplasia) were examined, and lesions that contained separate areas of hyperplastic and adenomatous glands were excluded. The Ki-67-positive rate in the middle zone of the crypts in serrated adenomas was significantly higher than in hyperplastic polyps but lower than in tubular adenomas; a similar tendency was also noted for the upper zone. Both serrated adenomas and hyperplastic polyps demonstrated Bcl-2-positive reactivity that was essentially limited to the lower crypt zone, while in contrast, involvement in tubular adenomas often extended to the middle zone. No p53 overexpression was found in any category. These results suggest that serrated adenomas may be committed to independent growth.

Adenoma↗

[Measurement of regional cerebral blood flow and glucose utilization in rat brain under chronic hypoperfusion conditions following bilateral carotid artery occlusion. Analyzed by autoradiographical methods].

OBJECTIVE: Although the pathology of chronic hypoperfusion in rat following bilateral carotid artery occlusion has been documented, long term changes in cerebral blood flow and metabolism have not been reported. In this study regional cerebral blood flow (rCBF) and regional glucose utilization (rCGU) were analyzed by autoradiographical methods, pathological observation of the brains was also conducted. METHODS: Male Wistar rats aged 12 weeks were anesthetized and the bilateral carotid arteries were occluded. Physiological parameters, ABG, MABP, and rectal temperature were measured before and through occlusion. After 2 days, 1, 4, and 8 weeks and controls of rCBF (Sakurada) and rCGU. (Sokoloff) were measured (n = 6). Evaluated regions included frontal cortex (Fcor), parietal cortex (Pcor), temporal cortex (Tcor), occipital cortex (Ocor), genu corpus callosum (gCC), corpus callosum (CC), splenium corpus callosum (sCC), caudate putamen (CPu), globus pallidus (GP), internal capsule (IC), thalamus (Thal), hippocampus CA 1 (CA 1), hypothalamus (HypoTh), amygdal (Amygd), and substantia nigra (SNR). In separate animals (n = 3) tissue sections were stained using Klüver-Barrera (KB) and Hematoxylin-Eosin (HE), and pathological changes were observed. RESULTS: After 2 days the rCBF values were significantly reduced to 33-58% of control values in the Fcor. Pcor, Tcor, Ocor, gCC, CC, sCC, CPu, GP, JC, and Amygd. The reductions were observed from the 2nd day to the 1st week. From the 1st week to the 4th week values began to recover to control levels. However, after 4 weeks they were still significantly reduced in the Ocor, gCC, CC, sCC, GP, IC, and SNR (51-63%). After 8 weeks, the rCBF values in the areas except white matter, CPu, GP, and Ocor, etc., recovered to approximately 90% of control levels. However, in the Ocor, gCC, CC, sCC, CPu, GP, and IC, they were still 70-89% of control levels. After 2 days the rCGU values were reduced to 56-95% (except Amygd) in the measured regions, although not as reduced as the rCBF levels. From the 2nd day to the 1st week, the rCGU values were reduced further and after 1 week the rCGU values were significantly reduced to 39-69% in the Fcor, Pcor, Tcor, Ocor, gCC, CC, sCC, CPu, GP, IC (Lt), Thal (Rt), Amygd, and SNR From the 1st week to the 4th week, the values began to recover to control levels. After 4 weeks, rCGU improved to approximately 90-100% of controls, and remained at that level through 8 weeks occlusion. Rarefaction of the myelinated fibers was observed in the white matter from the 1st week to the 4th week in the KB stained sections, while little change in cortex was observed throughout 1st to 8th week. CONCLUSION: In this chronic hypoperfusion model rCBF remained depressed after 8 weeks in the Ocor, white matter, and basal ganglia, and rarefaction of the white matter was observed. These results indicate that this model is suitable for the study of chronic cerebral hypoperfusion.

Animals↗

[Intraperitoneal single-dose toxicity studies of active metabolite, optical isomers, hydrolysis products and bi-product of (+/-)-4-diethylamino-1,1-dimethylbut-2-yn-1-yl 2-cyclohexyl-2-hydroxy-2-phenylacetate monohydrochloride monohydrate(NS-21), a novel drug for urinary frequency and incontinence, in mice].

NS-21, (+/-)-4-diethylamino-1,1-dimethylbut-2-yn-1-yl 2-cyclohexyl-2-hydroxy-2-phenylacetate monohydrochloride monohydrate, is a new drug for the treatment of urinary frequency and incontinence. To evaluate acute toxicities of its related compounds including the optical isomers of NS-21 ((S)NS-21 and (R)NS-21), the active metabolite of NS-21 ((R/S)RCC-36), the optical isomers of (R/S)RCC-36 ((S)RCC-36 and (R)RCC-36), the hydrolysis products of NS-21 (RCC-32 and RCC-38) and the bi-product of NS-21 (RCC-66), single-dose intraperitoneal toxicity studies were conducted in ddY mice. The LD50 values of these compounds in male and female mice were as follows: 199 and 184 mg/kg for (S)NS-21, 261 and 240 mg/kg for (R)NS-21, 74 and 100-150 mg/kg for (R/S)RCC-36, 93 mg/kg for (S)RCC-36 in both sexes, 83 and 104 mg/kg for (R)RCC-36, higher than 510 mg/kg for RCC-32 in both sexes, 340-510 mg/kg for RCC-38 in both sexes, and 1000-2000 mg/kg for RCC-66 in both sexes, respectively. The clinical signs included decreased spontaneous locomotor activity, prone or lateral position, ataxic gait, clonic convulsion, hypopnea, hypothermia, pale skin, mydriasis, abdominal distention and unkempt fur for (S)NS-21, (R)NS-21, (R/S)RCC-36, (S)RCC-36 and (R)RCC-36, decreased spontaneous locomotor activity, prone position, ataxic gait, clonic convulsion, tail elevation and hypopnea for RCC-32 and RCC-38, and decreased spontaneous locomotor activity and unkempt fur for RCC-66. Body weight was decreased or its gain was suppressed for every compound examined. Pathological examination of the dead mice showed atrophy of the thymus and spleen, intestinal distention with the retention of dark red contents, white spots or white materials in the abdominal fatty tissue for (S)NS-21, (R)NS-21, (R/S)RCC-36, (S)RCC-36, (R)RCC-36 and RCC-66, but no treatment related change for RCC-32 and RCC-38. Adhesion between the abdominal organs was observed in survivors treated with (S)NS-21, (R)NS-21, (S)RCC-36, (R)RCC-36, RCC-32 and RCC-66.

Animals↗

Cercarial density in the river of an endemic area of schistosomiasis haematobia in Kenya.

The cercarial density in natural water and number of infected Bulinus globosus were monitored over a one-year period to identify the transmission foci in an endemic area of schistosomiasis haematobia in Kenya. Overall prevalence and intensity of infection of the study community were 59.2% and 10.9 eggs/10 ml of urine. Cercariometry was carried out on 456 occasions at 20 study sites while snail sampling was done on 465 occasions at the same sites over a one-year period. Cercariometry was exclusively done at flowing water habitats. The results showed the focality and seasonality of transmission. Cercariae were detected on 44 occasions at 11 sites. The detections were made on seven occasions at two study sites, six occasions at one site, four occasions at four sites, three occasions at one site, two occasions at two sites, and one occasion at one site. Densities of 1-4 cercariae/100 liters of water were found on 31 occasions. Five to nine cercariae/100 liters of water were found on seven occasions, 10-19 cercariae/100 liters of water were found on two occasions, and high cercarial densities greater than 20 cercariae/100 liters of water were found on four occasions. The highest count was 52 cercariae/100 liters of water. The presence of cercariae in natural water was shown to depend on the water temperature, but the intensity and duration of sunlight did not affect the presence of cercariae in water. The monthly variability of cercarial density was proportional to the number of infected snails. Cercarial density was highest in March and April, in the middle of the rainy season, whereas no cercariae were detected in cool dry season. The snail population peaked late in March, the beginning of the long rainy season, remained high for two months, and decreased rapidly late in May when heavy rain occurred. The overall infection rate of snails was 7.3% and the majority of infected snails were collected from March to May. There was no definite correlation between the presence or absence of cercariae and infected snails. Cercariae were frequently found where infected snails were absent and cercariae were sometimes absent where infected snails were present. Cercariometry and snail sampling remain quite complementary in identifying the transmission foci of schistosomiasis.

Age Factors↗

[A case of intradural xanthogranuloma in the upper cervical spine].

An 18-year-old female patient suffered from posterior neck pain and gait disturbance. The neurological examination revealed left hemiparesis, general hyperreflexia and hypoalgesia on the right neck and upper limb, and left trunk and lower limb. MRI showed a large mass lesion in the right side of the spinal canal at the level of the C1 cervical spine, which was obviously compressing the spinal cord. An operation was performed through a right suboccipital craniectomy and right hemilaminectomy of the first vertebra. Though the mass lesion in the subarachnoid space compressed the spinal cord, it adhered neither to the spinal cord nor to the nerve roots. However, as it clearly adhered to the dura mater, the attachment site was also completely removed. In the pathological examination, lymphocyte, foamed macrophage and the giant cell of Touton type were shown. The immunohistochemical study with CD68 (Kp1) was positive, but it was negative for the lysozyme, neuron specific enolase and S-100 protein. The diagnosis was xanthogranuloma. The patient recovered completely after the operation. This is a rare case of juvenile type xanthogranuloma. This lesion in the spinal canal has usually its onset in the adult age.

Adolescent↗

Structural characterization of the N-linked carbohydrate chains of the zona pellucida glycoproteins from bovine ovarian and fertilized eggs.

The N-linked oligosaccharides that were released by hydrazinolysis from glycoproteins of zonae pellucidae of bovine ovarian eggs, were composed of neutral (23%) and acidic (77%) carbohydrate chains; almost all the acidic chains were neutralized by sialidase digestion. Sugar mapping analysis of pyridylaminated N-linked chains by reverse-phase and normal-phase HPLC and 500-MHz 1H-NMR spectroscopy revealed that the major neutral chain is a high-mannose-type oligosaccharide and the acidic chains are di-, tri-, and tetra-antennary, fucosylated complex-type chains that have N-acetyllactosamine repeats in the non-reducing regions. The structures of the neutral chain and the core regions of the acidic chains of N-linked oligosaccharides from the zona proteins of fertilized eggs, which were obtained by the in vitro fertilization method, were essentially the same as those of the ovarian egg zonae. The amount, however, of the acidic chains decreased to 32 mol/100 mol in the fertilized egg zonae, which suggests that a sialidase released from the oocyte during fertilization operates on the zona glycoproteins.

Animals↗

Utilization of a mass-infusion system in the management of ruptured abdominal aortic aneurysms: an alternative application for devices employed in cardiopulmonary bypass.

To stabilize the hemodynamics before and during ruptured abdominal aortic aneurysmal repair, a mass-infusion system was developed and successfully employed in the treatment of two patients. The system consists of a combination of devices used in cardiopulmonary bypass, namely: suction, a reservoir, a heat exchanger, a bubble trap, and an intracaval large-sized venous femoral cannula for infusion. It proved extremely useful to tide the patients over hypovolemic shock before cross-clamping of the proximal aorta, preventing intraoperative hypothermia, which is known to cause multiple physiologic derangement associated with an adverse outcome. Moreover, the employment of a large-sized cannula allowed for a temporary switch from the preceding venous infusion support to the hypothermic circulatory assist with central aortic cannulation, using the caval cannula for drainage. This system provides an optional advantage for patients requiring an open proximal anastomosis.

Aneurysm, Ruptured↗

An alternative procedure to intra-arterial aortoinfundibuloplasty.

Intra-arterial aortoinfundibuloplasty is a newly developed aortic annular enlargement procedure in which, originally, the annulus was split anteriorly via the main pulmonary arteriotomy. An alternative method of aortoinfundibuloplasty was studied experimentally which creates spiral incisions on the free walls of both great arteries descending together into the aortopulmonary and infundibular septum via both commissures of right and left facing cusps of pulmonary and aortic valves. The valve prosthesis is implanted through this three-dimensional incision, followed by patch reconstruction. The ratio of annular augmentation was three sizes in two animals and four sizes in three animals. Immediate postoperative haemodynamics were satisfactory and there was no significant postoperative increase in systolic pressure gradient at the right ventricular outflow tract and in the right ventricular end-diastolic pressure. This alternative procedure could be applied to cases requiring radical annular enlargement and would give a wider view of both ventricular outflow tracts.

Animals↗

Double balloon catheter for concomitant augmentation of abdominal organ perfusion during intraaortic balloon counterpulsation.

A newly devised double balloon catheter to augment abdominal organ perfusion concomitant with original cardiac assist during intraaortic balloon counterpulsation provided satisfactory hemodynamics and urinary output around cardiac surgical procedures in 2 patients with coronary artery disease. Some optional advantages in clinical application and problems arising in the catheter design which need to be investigated are discussed.

Acetylglucosaminidase↗

[Hemodynamic plus series of St. Jude medical valve prosthesis in aortic position: early clinical outcome and reconsideration of its application].

St. Jude Medical Hemodynamic plus bileaflet valve prosthesis (HP) was employed in 7 cases undergoing aortic valve replacement since December 1993. Echocardiographic evaluation of left ventricular dimension and transvalvular pressure gradient was performed in 5 cases with 19 HP before and after operation. Each data was compared with those of 21 cases having undergone aortic valve replacement with 19 mm Standard model (19 SD). There was no significant postoperative change in left ventricular end-diastolic dimension (50 +/- 4 mm to 44 +/- 8 mm; p = NS) and left ventricular end-systolic dimension (34 +/- 4 mm to 34 +/- 9 mm; p = NS) in 19 HP cases. However, left ventricular end-diastolic dimension (51 +/- 11 mm to 41 +/- 8 mm; p < 0.05) and left ventricular end-systolic dimension (35 +/- 12 mm to 28 +/- 9 mm; p < 0.05) decreased in 19 SD cases. Transvalvular systolic peak pressure gradient was reduced significantly in both groups (19 HP: 94 +/- 38 mmHg to 43 +/- 19 mmHg; p < 0.05, 19 SD: 73 +/- 49 mmHg to 33 +/- 14 mmHg; p < 0.05). Poor reduction of left ventricular volume and high residual systolic pressure gradient in patients with 19 HP might be due to relatively high incidence of stenotic lesion in original aortic valve disease. In some cases with these critical aortic stenosis, radical annular enlargement procedure would provide more fundamental release of left ventricular outflow tract stenosis rather than one size increase of effective orifice area by employing HPs. Structural examination demonstrated that 19 HP had the same outer diameter of sewing flange with identical orifice ring as 21 SD (24 mm) did, and 17 HP had that of 19 SD (22 mm). Therefore, precise attention is needed for application of SJM-19 HP in patients with small aortic annuli.

Adolescent↗