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Biomedical subjects

K Kumano

Publications and source records attributed to K Kumano.

At least 19 recordsLinked to original sources

Reduction of lumbar spondylolisthesis using a CDI pedicle screw system.

To evaluate reduction methods using two of the several types of Cotrel-Dubousset instrumentation (CDI), 39 patients with low-grade (Meyerding grades I and II [12]) lumbar spondylolisthesis were followed clinically and radiologically for a minimum of 6 months. Our surgical methods were classified into three types as follow: reduction by 2-level assembly using double-threaded screws (type I); reduction by single-level assembly using the double-threaded screws (type II); and reduction by single-level assembly using tulip screws (type III). We found that satisfactory reduction could be achieved by single-level assembly using either the double-threaded or tulip screw without resection of disc material or the posterior leverage method. We found that the tulip screw was superior in obtaining stable reduction. We discuss the mechanism of reducing spondylolisthesis in comparison with that of previously reported methods.

Adolescent

Intracerebral hematoma in patients with ruptured cerebral aneurysms.

BACKGROUND: Intracerebral hematoma from ruptured aneurysms is one of the unfavorable factors for outcome in patients with subarachnoid hemorrhage. In this study, the clinical characteristics of intracerebral hematoma in patients with ruptured aneurysms were examined. METHODS: The subjects were 512 patients who had been admitted by day 3 after aneurysmal rupture without episodes of rebleeding before the initial computed tomography (CT) scan. They were divided into two groups according to the findings of initial CT; groups 1 and 2 comprised patients with and without intracerebral hematoma, respectively. RESULTS: Of the 512 patients, intracerebral hematoma was observed in 98 (19%). The incidence of intracerebral hematoma was higher in patients with distal anterior cerebral and middle cerebral artery aneurysms, compared with those at other sites (both, p < 0.01). Interhemispheric, callosal, and temporal lobe/sylvian hematomas were observed more frequently in patients with anterior communicating, distal anterior cerebral, and middle cerebral artery aneurysms, respectively, than in those with aneurysms at other sites. The incidence of rebleeding was 22% in group 1 and 14% in group 2 (p < 0.05). Clinical grades on admission were higher and outcome at 6 months after onset was less favorable in group 1 than in group 2 (both, p < 0.01). The larger the intracerebral hematoma, the higher was the clinical grade and the less favorable the outcome. However, when comparing management and surgical outcome under the same clinical grades, there was no significant difference between the two groups. CONCLUSIONS: There was a close correlation between the site of hematoma and that of the ruptured aneurysm. Poor outcome in patients with intracerebral hematoma seems to be related to severity of clinical grade on admission.

Adult

Effect of rapid spontaneous diminution of subarachnoid hemorrhage on cerebral vasospasm.

In patients with subarachnoid hemorrhage (SAH), the effect of clot removal on cerebral vasospasm is still in dispute. The purpose of this study is to investigate whether rapid spontaneous diminution of subarachnoid blood alleviates vasospasm. We analyzed the effect of diminution of SAH on vasospasm in 36 patients with SAH grades III-IV who were operated on by the same surgeon by day 6 after SAH. The diminution of subarachnoid blood became more apparent with shorter interval between hemorrhage and initial computed tomography (CT) scan, with increasing patient age, and with higher SAH grades. The incidences of angiographic vasospasm grades III-IV, permanent symptomatic vasospasm, and low-density area on CT scans decreased with the increase in the degree of diminution of subarachnoid blood. Permanent symptomatic vasospasm and low-density area on CT scans were found in 5 of 9 patients with no diminution, whereas they occurred only in 5 of 27 patients with diminution (p < .05). We concluded that spontaneous diminution of subarachnoid blood in the acute stage after SAH seems to reduce the severity of vasospasm.

Aged

[Agents preventing decrease in ultrafiltration in a rat model with peritoneal hyperpermeability].

Ultrafiltration failure has been one of the major causes of drop out from CAPD treatment. The present study was designed to develop an ultrafiltration failure model in the rat and to assess whether various agents could prevent a decrease in ultrafiltration capacity in this rat model. Peritoneal hyperpermeability was induced by repeated intraperitoneal injection of 15 ml of 4.25% dextrose dialysate for 7 days. Some of the rats received agents, such as phosphatidylcholine, chondroitin sulfate, siliac acid, heparan sulfate, keratan sulfate, sodium sulfate, sodium phosphate, and heparin sodium, simultaneously administered with 4.25 % dextrose dialysate for the same duration. Ultrafiltration volume, D4/D0 ratio of glucose and peritoneal net fluid absorption were evaluated by 4-hour dwelling of 30 ml of 2.5% dextrose dialysate. Sodium phosphate and heparan sulfate prevented peritoneal hyperpermeability due to repeated injection of hypertonic dialysate. Sodium phosphate, sodium sulfate, heparin and heparan sulfate suppressed peritoneal net fluid absorption, resulting in an increase in ultrafiltration. These findings may be applicable to CAPD patients with ultrafiltration loss.

Absorption

Relationship between the anatomic and dermatomal levels of spinal cord tumors in the thoracic region.

In neurologic examination of patients with a suspected compressive lesion at the thoracic region, the dermatomic level of sensory disturbance is the only index indicating the anatomic level of a lesion. Because spinal cord tumors usually are solitary compressive lesions, the relationship between the anatomic and dermatomic levels is conveniently examined. We examined the relationship between the highest dermatomic level of sensory disturbance and the anatomic level, axial location, and type of spinal cord tumors in the thoracic region in 19 patients (8 men and 11 women aged 27-78 years; 11 neurinomas, 7 meningiomas, 1 neurofibroma). The distribution of sensory disturbance was evaluated with 3-g Frey hair and 1-g pin-prick examinations. The dermatomic distribution of sensory disturbance was diagnosed according to the dermatome chart of Keegan and Garrett. The anatomic level and axial location of the tumor were highly related to the sensory disturbance. Eight of 12 tumors in which the dermatomic level of sensory disturbance was within one vertebral segment of the anatomic level were situated in the middle or lower thoracic region (T6-T10). All five tumors in which the dermatomic level was two or more vertebral segments away from the anatomic level were situated at the conus medullaris (T12) or upper thoracic region (T1-T5); the highest level of sensory disturbance was from 4 to 11 segments below the anatomic level of the tumor. In two patients with no sensory disturbance, the tumor was in the upper thoracic region (T5) and compressed the spinal cord from the dorsal side. When a spinal cord tumor at the thoracic region is suspected, imaging examinations should be performed sufficiently cranially.

Adult

[Microbiological assay method for T-3761 concentration in body fluids].

A microbiological assay method for measurement of T-3761 and its stability in body fluids were investigated. The paper disc method proved suitable for this assay using Escherichia coli Kp as a test organism and commercially available heart infusion agar as a test medium. When using the paper disc method, lower detection limit of T-3761 was approximately 0.05 microgram/ml and 0.1 microgram/ml for 1/15M phosphate buffer (pH 7.0) and human serum, respectively. T-3761 in human serum and urine was stable under freezing -20 degrees C for at least 28 days.

Agar

[Absorption, distribution, metabolism and excretion of T-3761, a new quinolone derivative, in experimental animals].

We studied the absorption, distribution, metabolism and excretion of T-3761, a new quinolone derivative, in experimental animals. The following results were obtained. 1. The peak serum levels of T-3761 after a single oral administration to various fasting animals at a dose of 5 mg/kg were high in the order of rats, dogs, mice and rabbits, showing favorable absorption in all animals except for rabbits. In mice and rats, T-3761 showed higher peak serum levels than ofloxacin and ciprofloxacin but T-3761 were more rapidly eliminated from serum than ofloxacin and ciprofloxacin. 2. Tissue concentrations of T-3761 in rats were similar to those of ofloxacin but its ratio of tissue to serum levels were lower than those of ofloxacin. 3. Urinary excretion of T-3761 as active form until 24 hours after oral administration was 27.3%, 63.1%, 41.0% and 63.3% in mice, rats, rabbits and dogs, respectively. Only unchanged T-3761 was detected as active form in urine of all animals tested. In rats, urinary concentrations until 2 hours after administration were higher than those of ofloxacin. 4. Biliary excretion of T-3761 in mice and rats were 2.9% and 1.4% as active form. 5. The absorption of T-3761 was not different in male and female rats or 8 and 14 weeks old rats. The meal lowered absorption of T-3761 in rats. There was no significant difference in serum levels, urinary excretion and distribution to tissues after multiple administration of T-3761 comparing with its single administration. 6. In rats with liver dysfunction induced by D-galactosamine, the serum levels and urinary excretion were slightly higher than in normal rats. On the other hands, in rats with kidney dysfunction induced by HgCl2, the serum levels were significantly higher and urinary excretion of T-3761 was significantly lower than in normal rats. Above results show that T-3761 has unique characteristics in absorption, excretion and distribution after oral administration to animals among new quinolones, i.e., T-3761 was eliminated rapidly and poorly distributed to tissues but showed superior absorption and high peak serum levels.

Administration, Oral

[Effect of direct pulsatile peritoneal dialysis on peritoneal permeability and lymphatic absorption in the rat].

Continuous vibration of the abdominal wall with a small electric vibrator was conducted to enhance peritoneal mass transport in rats with normal kidney function. Thirty ml of either 2.5% or 4.25% dextrose dialysate containing creatinine, urea and dextran 70 was infused intraperitoneally and was allowed to dwell for 30-240 min with or without abdominal wall vibration at the rate of 80 Hz. The mass transfer area coefficient (KA) of small molecular solutes and peritoneal lymphatic absorption were investigated. Peritoneal dialysis with vibration for 60 min increased the KA of urea, creatinine and glucose by 12%, 15%, 27%, respectively, without changes in ultrafiltration and lymphatic absorption. This effect may be attributed to enhanced mixing of dialysate in the peritoneal cavity and the increased peritoneal effective blood flow. This concept can be applied to short-term dwell dialysis, such as automated peritoneal dialysis.

Absorption

[Detection of glomerular and non-glomerular red blood cells by automated urinary sediment analyzer].

There is increasing interest in the examination of urine sediment to differentiate between glomerular and non-glomerular hematuria. A newly developed automated urinary sediment analyzer was used for this purpose. It clearly recognized red blood cells, white blood cells, epithelial cells, bacteria and crystals by their cell size and fluorescent intensity. Ninety-eight urine samples from 31 glomerular and 67 non-glomerular lesions were analyzed by the analyzer and 69 samples, by light microscopy. According to the analysis of their histograms, a forward scatter (FSC) intensity of less than 126, where 80% of the smaller red blood cells were observed, was diagnosed as glomerular hematuria. A FSC intensity of more than 84, where 80% of the large red blood cells were counted, was non-glomerular hematuria. An FSC intensity between 84 and 126 was considered to be the overlap zone of glomerular and non-glomerular hematuria. The sensitivity for glomerular red blood cells was found to be 100% and specificity, 92.54% by means of flow cytometric analysis. On the other hand, light microscopic analysis yielded 95.83% sensitivity and 93.33% specificity for glomerular lesions. Flow cytometric analysis of the urinary red blood cells was concluded to be a fast, simple and reliable method to differentiate glomerular and non-glomerular hematuria.

Adolescent

Pedicle screws and bone mineral density.

STUDY DESIGN: Thirty-five consecutive patients who underwent surgeries for decompression, and one-level fusions with Cotrel-Dubousset pedicle screws for spinal canal stenosis were included in this study. The relationship between bone mineral density of the lumbar spine and the rate of successful fusion and screw problems was studied. OBJECTIVES: Bone mineral density of the third lumbar vertebral body was measured by quantitative computed tomography preoperatively, and the degree of osteoporosis was graded by radiographic films of lumbar spines. The films were followed with anteroposterior and lateral dynamic radiographic examinations of lumbar spines. These examinations were evaluated clinically after surgery. Follow-up duration was at least 19 months, with a mean of 28 months. SUMMARY OF BACKGROUND DATA: The mean bone mineral density of all the patients was 117.1 mg/mL (SD = 42.5). The rate of successful fusion was 88.6%, the non-union rate was 5.7%, and the rate of fusions that were undetermined was 5.7%. The incidence of screw loosening occurred in 5.7% of the patients, screw breakage occurred in 5.7% of patients, and symptomatic screws related to non-union were present in 5.7% of patients. The degree of bone mineral density or radiographic gradings of osteoporosis and the successful fusion or the incidence of symptomatic screws, which were defined as screws related to non-union, were not related. METHODS: The patients were divided into two groups. One group consisted of 12 patients who had less than 100 mg/mL of bone mineral density, with a mean of 72.0 mg/mL (SD = 21.2). The other group consisted of 23 patients who had more than 100 mg/mL of bone mineral density, with a mean of 140.6 mg/mL (SD = 30.0). The rate of successful fusion or non-union and the rate of screw problems such as screw loosening or screw breakage were compared in the two groups. The presence of bony trabeculation in grafted bone is the most important criterion for successful fusion. RESULTS: A statistical difference did not occur between the two groups. Non-union, screw breakage, and screw loosening were observed in patients with both increased and decreased bone mineral density and those with increased and decreased grade osteoporosis. Radiographic grading of osteoporosis was not correlated to bone mineral density, but patients with unexpected bone mineral density were frequent in this series. CONCLUSIONS: The use of decompression and pedicle screws for spinal canal stenosis due to degenerative lumbar disorders can be done safely with one-level fusion in patients with decreased bone mineral density if patients with grade III osteoporosis are excluded. Bone mineral density is more reliable than radiographic grading to evaluate the degree of osteoporosis and should be included in the preoperative evaluation of patients with osteoporosis.

Bone Density

A single stage posterior approach and rigid fixation for preventing kyphosis in the treatment of spinal tuberculosis.

STUDY DESIGN: The authors employed a new mode of treatment for spinal tuberculosis consisting of single stage posterior instrumentation and fusion without anterior debridement. Ten patients were operated upon in this manner. Chemotherapy was instituted 2 weeks preoperatively and continued for a mean period of 11 months. Cotrel-Dubousset or a comparable system was used for fixation. OBJECTIVES: Patients were followed for 3 monthly intervals with serial anteroposterior and lateral x-rays, erythrocyte sedimentation rate, physical examination, and patients' self reports. The mean follow up period was 24.2 months (range, 17-36 months). METHODS: Measurement of kyphosis angle in the lateral x-ray view was used to evaluate treatment. RESULTS: Only a 3.4 degrees mean loss of correction was observed over the follow-up period. All patients were satisfied. CONCLUSION: Our results show that posterior rigid fixation and chemotherapy provide satisfactory stabilization, reduce surgical morbidity, and prevent development of late kyphosis in selected patients with Pott's disease of the thoracolumbar spine.

Antitubercular Agents

Complication of silastic dural substitute 20 years after dural plasty.

A 63-year-old woman was admitted because of right hemiparesis. Both computed tomography scan and magnetic resonance imaging revealed a mass lesion in the left parieto-occipital lobe. Twenty years previously, meningioma of the left parieto-occipital region was removed at another hospital, and a dural plasty was performed using a silastic dural substitute. The patient was operated on under the diagnosis of recurrent meningioma. However, most of the mass lesion was composed of an old hematoma, which seemed to be a complication of the silastic dural substitute.

Aged

[Changes of plasma endothelin level in the early post-renal transplantation period].

Endothelin (ET) has been suggested to be involved in acute graft rejection of kidney transplantation and cyclosporin A (CsA) nephrotoxicity. For clarification of the pathophysiological role of ET in the early post-transplantation period, plasma endothelin-1 (ET-1) was measured by specific radioimmunoassay in renal transplant recipients, patients on maintenance hemodialysis (HD) and healthy volunteers. Twelve transplant recipients were used in this study, 8 of whom were living related subjects and 4 cadaver. Plasma ET-1 and graft function were measured each day, from 1 day prior and 7 days following transplantation and every week up to 5 weeks postoperatively. Plasma ET was measured in 20 other transplant recipients with stable function (serum creatinine < or = 1.8 mg/dl), 20 maintenance HD patients with no residual renal function and 6 healthy volunteers. Mean plasma ET-1 was 13.0 +/- 4.5 pg/ml in 20 recipients with stable graft function, 21.7 +/- 6.5 in 20 HD patients and 1.5 +/- 0.4 in healthy volunteers. These differences are statistically significant (p < 0.02). Plasma ET-1 showed significant decrease from 21.8 +/- 7.2 pg/ml prior to transplantation to 12.8 +/- 4.0 when urinary output reached more than 1000 ml in living and cadaveric transplantation subjects. All three acute vascular rejections clearly indicated histologically increased plasma ET-1 accompanied by an increase in serum creatinine. A significant positive liner correlation was noted between plasma ET-1 and serum creatinine during the first week following living transplantation. Two patients with clinically and histologically suspected CsA nephrotoxicity showed transient increase in plasma ET-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

[Ultrafiltration failure in a peritoneal dialysis patient due to a marked increase in lymphatic absorption a case report].

A peritoneal dialysis patient was reported who had ultrafiltration loss due to a marked increase in lymphatic absorption and peritoneal membrane permeability. A 33-year-old male was transferred from hemodialysis to peritoneal dialysis because of acute subdural hematoma. His complicated history included left testicular tumor with retroperitoneal lymph node metastasis in 1982. He was treated with CDDP, Etoposide, Bleomycin, Vinblastine sulfate and Vincristine and received operation of retroperitoneal lymph node dissection in 1982. He had been on hemodialysis since 1983 due to cisplatinum nephropaty. Ultrafiltration failure was found immediately following the insertion of Tenckhoff catheter without malfunction of peritoneal catheter. Peritoneal equilibrate test and lymphatic absorption measurement showed a high permeability peritoneum with a marked increase in lymphatic absorption rate (3.7 ml/min). These two factors were thought to result in ultrafiltration loss. CAPD with 4-6 times exchange daily did not maintain ultrafiltration, because it gave approximately 2000 ml negative water balance every day. He was well maintained on a short time exchange intermittent peritoneal dialysis (IPD) with cycler using 18 L for 8 hours. We concluded that increased lymphatic absorption is one of the important factors for ultrafiltration fafilure and IPD with frequent exchange by cycler is suitable for the patient with ultrafiltration loss.

Absorption

[Effects of osmotic agents for cold kidney preservation].

The beneficial effect of UW solution may result from its ability to prevent tissue edema during cold storage. This study was conducted to determine which impermeant was effective in this regard during cold storage of a rat kidney in solution. Functional and morphological studies were made on a rat isolated perfused kidney (IPK) following 24 hour-cold storage in various tested solutions. Right nephrectomy was performed in 95 male rats by the method of Nishitsutsuji-Uwo et al and the kidney was perfused and stored at 4 degrees C for 24 hours as follows: glucose (194 mM) as a control, mannitol, sucrose, raffinose (140 mM in each), lactobionate (100 mM), raff + lact, hydroxyethyl starch 20, 40 (5%) with electrolyte composition essentially the same as that of Euro-Collins or UW solution. Kidneys stored for 24 hrs at 4 degrees C were perfused by the IPK apparatus. The perfusate flow rate was adjusted to maintain the renal arterial perfusion pressure at 100 mmHg. Raff, raff + lact or UW solution showed significantly higher fractional reabsorption of sodium than the control with no change in renal hemodynamics. The release of LDH into the perfusate was significantly less in raffinose than the control. Raffinose may thus be considered to function effectively as an impermeant for cold kidney preservation and molecule size would appear more important than negative charge for rat kidney preservation.

Animals