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T Kano

Publications and source records attributed to T Kano.

At least 37 records · Page 2Linked to original sources
PubMed2000

Autologous iris pigment epithelial cell transplantation in monkey subretinal region.

PURPOSE: To establish autologous iris pigment epithelial (IPE) cell transplantation in monkey eyes. METHODS: Autologous IPE cells from three monkeys were obtained by peripheral iridectomy, and cell culture was performed with autologous serum. The cultured cells were labeled with DiI, and transplantation was performed by transvitreal approach to the submacular region of each monkey. Fundus examination, photography, and fluorescein angiography were performed monthly. Histochemical analysis and electron microscopy were also performed six months after transplantation. RESULTS: Auto IPE cells grew well in auto serum. No fluorescein leakage or retinal thickening was observed after submacular transplantation. We demonstrated the presence of autologous IPE cells in the region 6 months after transplantation by histologic and electron microscopic examination. Electron microscopy also demonstrated that the transplanted cells appeared to be less pigmented and to have less mitochondria than did the host retinal pigment epithelial cells. However, some transplanted cells looked as if they embrace the photoreceptor outer segments. DISCUSSION: Autologous IPE cell culture of the monkey was established using auto serum. Six months after transplantation of the cultured IPE cells, we could still observe the cells in the region. This method may have potential use in human disease that requires autologous cell transplantation to prevent host-graft rejection, and to provide an alternative substance that functions like retinal pigment epithelium.

Animals↗
PubMed2000

[Intraoperative hemodilutional autotransfusion using a closed circuit for patients of Jehovah's Witness].

We conducted hemodilutional autotransfusion using a closed circuit combined with a cell washing reinfusing system (Cell Saver) for two surgical patients of Jehovah's Witness. One was a 12 yr-old boy for extirpation of the teratoma in the anterior mediastinum and another was a 44 yr-old woman for left total hip replacement. The patients and their relatives had consented to the use of blood substitutes, hemodilutional autotransfusion using a closed circuit and Cell Saver. We devised a closed circuit system for hemodilutional autotransfusion combined with Cell Saver, in which two pumps for blood transfusion were used; one was for drawing blood from the femoral or the internal jugular vein and the other for returning blood to the peripheral vein. Blood volume in a bag interposed in the closed circuit was easily controlled by adjusting the speed of each pump. Blood collected from the surgical field by Cell Saver was also led to the bag. Acid citrate dextrose solution was infused into the closed circuit from the site close to the blood drawing. Both of our surgical patients were safely managed without homologus blood transfusion, although there remained some problems concerning the use of anticoagulants.

Adult↗
PubMed2000

[Malignant islet cell tumor of the pancreas with multiple liver metastases effectively treated by transcatheter arterial embolization with degradable starch microspheres--a case report].

A 57-year-old woman underwent distal pancreatectomy for malignant islet cell tumor of the pancreas in 1991. One year later, multiple liver metastases appeared. Although three transcatheter arterial embolizations (TAE) with spongel and nine ethanol injections were performed over seven years, the tumors were growing gradually. Therefore, TAE with degradable starch microspheres (DSM) was selected. Under angiography, TAE of the left hepatic artery was done using 900 mg of DSM following injection of Farumorubicin (20 mg), Lipiodol (3 ml) and cisplatin (90 mg). The tumors in the embolized hepatic area were remarkably decreased in size, and satisfactory local control was obtained. Thereafter, TAE with DSM was carried out twice, and she is still living with outpatient treatment. Thus, it is suggested that TAE with DSM could be a promising, alternative therapeutic modality for liver metastases from malignant islet cell tumor of the pancreas.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Effects of intensive lipid lowering by low-density lipoprotein apheresis on regression of coronary atherosclerosis in patients with familial hypercholesterolemia: Japan Low-density Lipoprotein Apheresis Coronary Atherosclerosis Prospective Study (L-CAPS).

Twenty-five heterozygous familial hypercholesterolemic patients treated with LDL-apheresis and drugs and 11 patients treated with drugs underwent follow-up angiography 2.3 years later. One-hundred thirteen lesions were measured by quantitative angiography. Mean LDL-cholesterol levels during the trial were 140 +/- 34 mg/dl in the apheresis group and 170 +/- 58 mg/dl (P < 0.05) in the control group. The mean changes in minimal lumen diameter of lesions were +0.19 +/- 0.30 mm (improved) in the apheresis group (n = 76) and -0.44 +/- 0.40 mm (worsened) in the control group (n = 37) (P < 0.0001). When progression and regression were defined as a change in minimal lumen diameter of +/- 0.67 mm, in the apheresis group, two (8%) patients had progression, 19 (76%) stayed unchanged and four (16%) had regression, but in the control group seven (64%) patients had progression and four (36%) stayed unchanged. The frequency of regression or no change was significantly higher in the apheresis group than in the control group (P < 0.004). Intensive cholesterol lowering therapy with LDL-apheresis and lipid lowering drugs can achieve a substantial decrease in LDL-cholesterol levels to induce regression of coronary lesions in familial hypercholesterolemic patients with advanced coronary artery disease.

Adult↗
PubMed1999

Effects of a bolus injection of adenosine triphosphate on atrioventricular conduction and hemodynamics in patients undergoing coronary artery bypass grafting.

OBJECTIVE: To investigate the effects of adenosine triphosphate (ATP) on atrioventricular (A-V) conduction and hemodynamics in patients undergoing coronary artery surgery. DESIGN: A prospective study. SETTING: University teaching hospital. PARTICIPANTS: Patients scheduled for elective coronary artery bypass graft surgery. INTERVENTIONS: Anesthesia was induced with the same dose of intravenous fentanyl (300 microg) and midazolam (10 mg) for each patient. After the baseline measurement, a bolus dose of 10 mg of ATP (0.19+/-0.03 mg/kg, mean +/- SD) was rapidly injected through a central venous catheter. Right ventricular pacing was conducted at a rate of 40 beats/min during the development of complete A-V block. MEASUREMENTS AND MAIN RESULTS: ATP induced an A-V block in 10 of 12 patients (2:1 block in two patients and complete A-V block in eight patients). The onset of the A-V block was rapid (17.1+/-3.4 seconds) and the duration was short (12.1+/-7.0 seconds). Radial arterial pressure (AP) decreased with the appearance of the A-V block (p < 0.01). Heart rate (HR) returned to the baseline value quickly after the restoration of the A-V block, but recovery of radial AP was delayed. HR increased 1 minute after the ATP injection (p < 0.01). Both HR and radial AP returned to the baseline values 2 minutes after the ATP injection. ST segments on both leads II and V5 of electrocardiograms decreased more than 0.10 mV 1 minute after the ATP injection in one patient. CONCLUSION: A bolus injection of 10 mg of ATP successfully induced a transient A-V block in 83% of the 12 patients. The countermeasures, including ventricular pacing, are indispensable to cope with the subsequent hypotension that may lead to myocardial ischemia, especially in patients with ischemic heart disease.

Adenosine Triphosphate↗
PubMed1999

Computed tomographic epidurography: an aid to understanding deformation of the lumbar dural sac by epidural injections.

Local anaesthetics injected into the epidural space may deform the dural sac to a variable degree, thereby contributing to variability in the extent of the block. We investigated deformation of the lumbar dural sac after injection into the lumbar epidural space. The subjects were 26 patients with low-back pain who underwent lumbar epidurography and computed tomographic (CT) epidurography, of whom seven also underwent myelography and computed tomographic myelography. The epidural space was entered via the sacral hiatus in 24 patients and through the L5/S1 interspace in two patients. Ten millilitres of local anaesthetic was then injected into the epidural space followed by 20 mL of contrast medium. Computed tomographic epidurography was undertaken approximately 30-min after the epidural injection at the mid-vertebral and mid-discal levels from the first lumbar through to the first sacral vertebrae. The dural sac usually showed an oval or hexagonal shape on the transverse views at the first and second lumbar vertebral levels, and the shape of an inverted triangle below the level of the third lumbar vertebra. A median line of translucency was also observed on the posteroanterior epidurographic view in 25 of the 26 patients. This line was though to be a manifestation of the dural deformation to the inverted triangle. Dural sac deformation usually shows a specific pattern, although there are individual variations. Dural deformability is an important consideration in any analysis of the spread of epidural block or of the changes of epidural pressure after epidural injection of local anaesthetics.

Adult↗
PubMed1999

Effects of tissue type plasminogen activator in embolic versus mechanical models of focal cerebral ischemia in rats.

Tissue type plasminogen activator (tPA) can be effective therapy for embolic stroke by restoring cerebral perfusion. However, a recent experimental study showed that tPA increased infarct size in a mouse model of transient focal ischemia, suggesting a possible adverse effect of tPA on ischemic tissue per se. In this report, the effects of tPA in two rat models of cerebral ischemia were compared. In experiment 1, rats were subjected to focal ischemia via injection of autologous clots into the middle cerebral artery territory. Two hours after clot injection, rats were treated with 10 mg/kg tPA or normal saline. Perfusion-sensitive computed tomography scanning showed that tPA restored cerebral perfusion in this thromboembolic model. Treatment with tPA significantly reduced ischemic lesion volumes measured at 24 hours by >60%. In experiment 2, three groups of rats were subjected to focal ischemia via a mechanical approach in which a silicon-coated filament was used intraluminally to occlude the origin of the middle cerebral artery. In two groups, the filament was withdrawn after 2 hours to allow for reperfusion, and then rats were randomly treated with 10 mg/kg tPA or normal saline. In the third group, rats were not treated and the filament was not withdrawn so that permanent focal ischemia was present. In this experiment, tPA did not significantly alter lesion volumes after 2 hours of transient focal ischemia. In contrast, permanent ischemia significantly increased lesion volumes by 55% compared with transient ischemia. These results indicate that in these rat models of focal cerebral ischemia, tPA did not have detectable negative effects. Other potentially negative effects of tPA may be dependent on choice of animal species and model systems.

Animals↗
PubMed1999

Lens epithelial changes and mutated gene expression in patients with myotonic dystrophy.

AIMS: Examination of the expression of the mutated allele of myotonic dystrophy protein kinase gene and lens epithelial cell changes in patients with myotonic dystrophy. METHODS: Six eyes from three patients with myotonic dystrophy underwent cataract surgery. The lens epithelium was photographed to examine the morphological changes. mRNAs were extracted to determine myotonic dystrophy protein kinase gene expression in the lens epithelium and peripheral blood. Age matched lens epithelial cells from senile cataracts were used as controls. RESULTS: All eyes showed iridescent or posterior subcapsular lens opacity. The expression of the myotonic dystrophy protein kinase gene with trinucleotide repeat expansion was evaluated by reverse transcriptase polymerase chain reaction, Southern blotting, and sequence analysis. Lens epithelial cell densities were extremely reduced in the patients compared with the control group. CONCLUSION: To the authors' knowledge, this is the first report to describe the relation between lens epithelial cell changes and mutated gene expression in patients with myotonic dystrophy. The gene may be mitotically unstable in the lens epithelial cells; it may influence cell density and lens epithelial function, and it may lead to the development of typical subcapsular lens opacity.

Adult↗
PubMed1999

Functional analysis after auto iris pigment epithelial cell transplantation in patients with age-related macular degeneration.

Recent transplantation studies indicate that subretinal space is not always an immunologically privileged site and non-autologous cells may be rejected in patients with exudative age-related macular degeneration (AMD). We performed autologous iris pigment epithelial (IPE) cell transplantation by cell suspension after autologous IPE cell culture in 8 patients with AMD. These patients were followed without immunosuppression between 1.5 and 8 months and the retinal function was analyzed. No cystoid macular edema or fluorescein leakage was observed. Six of the 8 patients improved visual acuity of more than two lines and the other two patients retained preoperative visual acuity. Five patients had increased visual field sensitivity, one patient retained pretransplantation sensitivity, and one patient showed a gradual decrease in sensitivity (one patient was not examined). Although 2 of the 8 patients showed decreased amplitude of flicker electroretinography (ERG) (about 60 to 70% as that of preoperative level), the average improvement of each amplitude of a single white flash (a wave), photopic, or flicker ERG was 123, 102, and 107%, respectively. No proliferative change in the submacular lesion or vitreous cavity was observed after transplantation. From this functional analysis, transplanted autologous IPE may have, in part, an alternative function in regard to the retinal pigment epithelium in the subretinal space.

Aged↗
PubMed1999

[Unruptured aneurysm of the right sinus of Valsalva: a case report].

A previously healthy and asymptomatic 45-year-old woman was referred for evaluation of a heart murmur and an unusual dilatation in the aortic root. Transthoracic and transesophageal echocardiography, computed tomography, magnetic resonance imaging, and cardiac catheterization revealed an aneurysm with a maximum diameter of 6.0 cm in the right sinus of Valsalva. Aortic regurgitation and stenosis at the right ventricle outflow tract were associated with the aneurysm. Surgery and histological study demonstrated that the sinus of Valsalva aneurysm was enormously dilated with idiopathic degenerative change in the aortic media. The aneurysm was tremendously large compared to any previously reported. Decrease in pressure load during diastole caused by aortic regurgitation probably resulted in the growth of this huge aneurysm without rupture.

Aortic Aneurysm↗
PubMed1999

[Intraoperative assessment by laser-Doppler skin blood flowmetry of the efficacy of endoscopic thoracic sympathectomy].

We have investigated whether laser-Doppler (L-D) skin blood flowmetry on the finger could be useful for an intraoperative assessment of the efficacy of endoscopic thoracic sympathectomy (ETS) under general anesthesia. Subjects were 5 young adults receiving ETS for palmar hyperhidrosis. ETS was performed with the patients in the semi-sitting position under one lung ventilation. A pair of LDF probes were placed on the palmar side of the both second fingers. Palmar hyperhidrosis disappeared after ETS in all cases, but compensatory hyperhidrosis developed in the back of the body and the thigh. After completion of ETS on one side, the L-D skin blood flow increased to 267.6 +/- 211.1% on the side of ETS, and it increased in 2 other cases and decreased on the contrary in 3 cases on the other side. After ETS on both sides the L-D skin blood flow increased to 265.0 +/- 185.9% on the side of initial ETS and to 211.4 +/- 172.8% on the side of subsequent ETS. The initial EST induced reflex vasoconstriction on the finger of both sides and also on the toe. Spontaneous fluctuation and reflex vasoconstriction of the skin blood flow were still observed, although the periodicity of spontaneous fluctuation between the right and the left finger was lost in some of the cases. An increase in L-D skin blood flow on the side of ongoing ETS is useful for intraoperative assessment of ETS.

Adult↗
PubMed1999

[Contralateral cerebellar infarction after aneurysmal clipping with pterional craniotomy: report of two cases].

A 77-year-old woman underwent right fronto-temporal craniotomy for a right ruptured IC-PC aneurysm (case 1), and a 44-year-old woman underwent right fronto-temporal craniotomy for a right ruptured BA-SCA aneurysm (case 2). They were clipped completely without any troubles during surgery. But postoperative CT scan demonstrated contralateral cerebellar infarction. We recognized left-hand tremor as a neurological deficit caused by cerebellar infarction in case 1. Concerning the mechanism of contralateral cerebellar infarction after pterional craniotomy, we think that it could be; --1) changing of venous blood flow by overdrainage of cerebrospinal fluid, 2) destruction of the bridging vein because of cerebral transformation with rapid decompression, 3) ischemia caused by brain retraction and compression during operation, 4) hypertension or hypoxia during operation, 5) crossed cerebellar diaschosis, and so on. In our 2 cases, we believe that perioperative CSF overdrainage caused the contralateral cerebellar infarction or CCD. To avoid this kind of infarction, we should try to take more protective and careful procedures as well as closer perioperative management.

Adult↗
PubMed1999

[A patient with hepatic metastasis of breast cancer successfully treated with combined chemoendocrine therapy using epirubicin, tegafur and tamoxifen].

A solitary 1 cm sized metastatic lesion was found in the S5 region of the liver on a postoperative ultrasound screening of a 52-year-old breast cancer patient. It was confirmed by CT, MRI and hepatic angiography. At first, she was successfully treated with trans-arterial pirarubicin and lipiodol infusion but a metastatic lesion of similar size was found 6 months later in the same region. We then administered a triple 20 mg dose of epirubicin intravenously, and 450 mg of UFT and 30 mg of tamoxifen daily. Six months later the lesion had disappeared on US and CT scans and a complete remission has persisted for 18 months.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Characterization of mitochondrial glutaminase and amino acids at prolonged times after experimental focal cerebral ischemia.

The mitochondrial enzyme glutaminase is a significant contributor to extracellular glutamate after neuronal injury in vitro [R. Newcomb, X. Sun, L. Taylor, N. Curthoys, R.G. Giffard, Increased production of extracellular glutamate by the mitochondrial glutaminase following neuronal death, J. Biol. Chem. 272 (1997) 11276-11282.]. As a step towards characterizing the role of the enzyme in neuronal injury in vivo, glutaminase activity was measured in central and peripheral regions of the ischemic distribution in rat brain at 6, 24, and 48 h after permanent focal ischemia. Although glutaminase activity decreases in the central ischemic area, significant activity remains in peripheral areas of evolving damage, even after 24 and 48 h ischemia. Western blots show no detectable change in glutaminase molecular weight or total immunoreactivity, regardless of the degree of inactivation. Significant amounts of glutamine remain in ischemic tissue at prolonged times after focal ischemia, while reductions in tissue amounts of glutamate are highly correlated with decreases in glutaminase activity. In vivo microdialysis probes were inserted into the ischemic periphery after 24 h focal ischemia. Glutamate is significantly elevated in these dialysates. Perfusion of the glutaminase substrate glutamine and the enzyme activator phosphate results in further and specific elevations in dialysate glutamate. In sum, significant mitochondrial glutaminase activity remains in the periphery of the ischemic lesion at 24 and 48 h, where it can contribute directly to elevated extracellular glutamate. Inactivation of the glutaminase in central areas of the ischemic lesion does not involve significant proteolytic degradation, and likely involves a specific molecular event.

Amino Acids↗
PubMed1998

Management of recurrent pilocytic astrocytoma with leptomeningeal dissemination in childhood.

Two cases of recurrent pilocytic astrocytoma with leptomeningeal dissemination (LMD) are described. A 6-year-old boy presented with a cerebellar tumor, which was subtotally removed. Tumor recurrence with LMD occurred 4 years later. Reoperation for tumor removal followed by craniospinal irradiation stabilized the LMD over 5 years. A 4-year-old girl presented with a chiasmatic-hypothalamic tumor. Partial removal of the tumor was followed by radiation therapy. Tumor regrowth with LMD occurred 4 years later and was managed by reoperation, chemotherapy and radiotherapy. Tumor recurrence with LMD can be stabilized by multimodal treatment without tumor progression.

Arachnoid↗