Biomedical subjects

K Kaneda

Publications and source records attributed to K Kaneda.

At least 163 records · Page 9Linked to original sources

PubMed1998

[Techniques for evaluating neuronal death of the retina in vitro and in vivo].

This review describes the techniques to evaluate retinal neurodegeneration induced by excitatory amino acids and transient ischemia. Glutamate-induced neurotoxicity was examined in cultured rat cortical cells. Cultures obtained from the retinas of fetal rats were incubated in Eagle's minimal essential medium supplemented with 10% fetal calf serum or 10% horse serum at 37 degrees C in a humidified 5% CO2 atmosphere for 10-14 days. The neurotoxicity induced by glutamate was quantified by trypan blue exclusion. The viability of cultures was markedly reduced by a 10-min exposure to glutamate followed by incubation with glutamate-free medium for 1 hr. N-methyl-D-aspartate (NMDA)-induced retinal damage was examined in adult rats. Transverse sections of the retinas through the optic disk were stained with hematoxylin and eosin. A single intravitreal injection of NMDA damaged the ganglion cell layer and the inner plexiform layer without affecting the other retinal layers 7 days after injection. Retinal ischemia was induced by elevating the intraocular pressure for 45 min through the needle which was placed in the anterior chamber. Ischemia-induced retinal damage was inhibited by MK-801. These results indicate that the techniques described in this review can be employed to develop new drugs possessing neuroprotective action against neurodegeneration that occurs during retinal ischemia.

Animals↗

PubMed1998

Combination of low back pain and previous low back pain and shoulder stiffness in construction employees.

A postal questionnaire for the prevalence of low back pain was studied with relevance to stiffness of that shoulder and a history of low back disorders in construction employees. The percentage of clerical employees with low back pain was 31.3% and of field workers was 30.3%. Odds ratios representing a relative risk factor for low back pain relating to each age group showed 2.35 in the clerical and 2.10 in the field workers at the age of 30-34 years, and 3.34 and 2.58 at the age of 35-39 years, respectively. In the persons with positive previous low back pain, the prevalence rate of low back pain was 52.6% in the clerical, and 50.2% in the field workers. Odds ratios for low back pain relating to previous low back pain significantly exceeded unity for the clerical employees (OR = 9.53) and the field workers (OR = 10.28), compared to those without a history of previous low back pain. The incidence of stiffness of the shoulder was 48.2% in the clerical and 45.2% in the field workers, and the prevalence rate of low back pain among those with stiffness of the shoulder was 68.5% in the clerical and 65.8% in the field workers. Odds ratio were 3.03 in both groups. Among each age group, the prevalence rate of stiffness of the shoulder with low back pain increased gradually to a maximum in the 45-49 age group of 19%, and then dropped. In those with a history of low back pain and/or stiffness of the shoulder, the prevalence of low back pain showed significantly greater value than other risk factors.

Adult↗

PubMed1998

A placebo-controlled, single-blind study to determine the appropriate alendronate dosage in postmenopausal Japanese patients with osteoporosis. The Alendronate Research Group.

Alendronate (4-amino-1-hydroxybutylidene-1,1-bisphosphonate) is a potent inhibitor of bone resorption. The efficacy and safety of 36 weeks of treatment with alendronate were evaluated in Japanese women with osteoporosis, osteoporotic osteopenia or artificial menopause. The bone mineral density (BMD) of the lumbar vertebrae, markers of bone and calcium metabolism and clinical symptoms were monitored. A total of 113 randomly selected patients with osteoporosis or osteopenia were enrolled in the study, of whom 12 were excluded from the analyses because of lack of data. As a result, 101 patients were evaluated for the safety of the drug. Since eight patients were excluded from the efficacy analysis, 93 were evaluated. The incidence of adverse effects in the placebo (P), alendronate 2.5 mg/day (L) and alendronate 10 mg/day (H) groups increased with increasing dose of alendronate, being 6.1, 14.3 and 18.2%, respectively. The most common adverse effects were gastrointestinal symptoms, none of which was serious. Lumbar BMD increased after 36 weeks of drug administration to 5.21%, 5.64% and -0.90% in the L, H and P groups, respectively (P < 0.001, L vs. P and H vs. P). Serum alkaline phosphatase activity, serum osteocalcin and urinary deoxypyridinoline excretion were significantly decreased in a dose-related manner. Serum calcium and phosphorus were also significantly decreased after alendronate administration. Serum intact PTH was transiently increased. The present results indicate that alendronate effectively decreases bone turnover in a dose-related manner and increases lumbar BMD at a dosage of 2.5 mg/day, the lowest dose used in this study, in Japanese patients with osteoporosis.

Adult↗

PubMed1998

Acellular calcified columns in the normal growth plate of mouse vertebrae.

The present study aims to demonstrate the calcified columnar structures of the growth plate of mouse vertebrae and to show their age related changes. For light microscopy, paraffin sections of decalcified lumbar spines were stained with hematoxylin-eosin or toluidine blue; methacrylate sections of undecalcified specimens were stained to detect calcium precipitate. For scanning electron microscopy, lumbar spines treated with 5% NaClO solution were dehydrated by acetone and metal-coated. Light microscopy of hematoxylin-eosin stained sections revealed that the acellular columnar structures appeared between the chondrocyte stacks in the growth plate. These structures were stained more densely by toluidine blue. The methacrylate-embedded sections for calcium staining showed calcium deposition in the columns. Scanning electron microscopy of NaClO-treated specimens enabled the direct observation of the columns on both the epiphyseal and diaphyseal bone surfaces facing the cartilaginous growth plate. Numerous projections on each surface were distributed in mirror images ; the corresponding projections were similar in size and shape, indicating that the projections bonded with each other and formed calcified columns in the cartilaginous growth plate. Longitudinal sections of the spine confirmed these findings. The calcified columns first appeared about 2 or 3 weeks of age and increased in number with time. While increasing in number, they also grew in size fusing with the neighboring ones. The proportional area of the columns occupying the surface facing the growth plate also increased with age. These findings indicate that the calcified column ultimately concerns the cessation of the bone growth.

Aging↗

PubMed1998

CJ-12,373, a novel topoisomerase II inhibitor: fermentation, isolation, structure elucidation and biological activities.

A novel isochroman carboxylic acid CJ-12,373 was isolated from Penicillium sp. CL22557. CJ-12,373 inhibits both DNA gyrase-mediated supercoiling and relaxation without the formation of a cleavage intermediate, suggesting that CJ-12,373 inhibits DNA gyrase at a stage distinct from the religation step. CJ-12,373 is not selective for procaryotic DNA gyrase as it also inhibits relaxation mediated by eukaryotic topoisomerase II. The antimicrobial potency of CJ-12,373, however, is largely attributed to its inhibition of DNA gyrase.

Anti-Bacterial Agents↗

PubMed1998

A case of intraductal papilloma of breast in advanced age.

Breast tumors have their various biological characteristics as to advanced age of patients. Intraductal papilloma is a benign tumor of the breast which is known to occur in the premenopausal young females. Tumors of the breast in the senile females are found mainly to be breast cancers. No any cases of intraductal papilloma over 80-years were reported in Japan to date. We have recognized mammary tumors in old aged patients to be cancers, but it is necessary to put it into mind there are a few intraductal papillomas even if advanced in age. In this report, we present the most senile case with intraductal papilloma in our institute.

Aged↗

PubMed1998

[Acute renal failure in non-fulminant acute hepatitis without hepatitis A, B or C virus infection].

Here, we report a 35-year-old man with non-fulminant acute non A, non B, non C hepatitis which developed into acute renal failure. The patient was admitted to hospital with the chief complaints of general fatigue, nausea and a high-grade fever of 40 degrees C. Laboratory examination revealed severe liver dysfunction and renal insufficiency on admission: his serum glutamic oxaloacetic transaminase was 3.203 IU/ml, serum glutamic pyruvic transaminase was 3.825 IU/ml, lactic dehydrogenase was 2.840 IU/ml, blood urea nitrogen was 65 mg/dl, and creatinine was 7.6 mg/dl. Hemodialysis was conducted during the initial 19-day period after admission because anuria was manifested on admission. On the 36th day after onset, renal functions returned to normal and the patient was negative for IgM-HA antibody. HBs antigen, IgM-HBC antibody, HCV antibody, cytomegalovirus antibody, and Epstein-Barr virus antibody. However, liver biopsy for histological examination on the 44th day after onset revealed no specific findings except the healing stage of acute hepatitis. Renal biopsy on the 49th day showed the healing stage of acute tubular necrosis without any glomerular change. It has been infrequently reported that acute renal failure develops following a non-fulminant acute state without hepatitis A, B or C virus infection. It is necessary to take acute renal failure into account in the clinical course of non-fulminant non A, non B, non C hepatitis.

Acute Disease↗

PubMed1998

[Clinical experiences of minimally invasive direct coronary artery bypass (MIDCAB)].

From Jan. to Oct. in 1997, we performed 18 minimally invasive direct coronary artery bypass (MIDCAB), aged from 45 to 86 years (the mean age of 69 years). They had single LAD disease post PTCA failure in 2 patients, and multiple vessel disease in 16 patients including left main stenosis in 2 patients. Sixteen patients had associated risk factors for using cardiopulmonary bypass, such as cerebrovascular disease in 9 patients, calcification of ascending aorta in 5 patients, renal failure in 2 patients, old age over 80 years in 4 patients and cancer in one patient. Single bypass grafting of left internal thoracic artery (LITA) to left anterior descending artery (LAD) underwent through left anterior small thoracotomy in 9 patients, double bypass grafting of gastroepiploic artery or right ITA to right coronary artery with LITA to LAD in 9 patients through subxiphoid small incision or right anterior small thoracotomy. The mean number of distal anastomosis was 1.5/patient. All patients are alive and asymptomatic, and postoperative angiography demonstrated the patency rate of 96.2% (26/27). MIDCAB is considered as a justified and safe technique for the patients who are ineligible for standard coronary artery bypass grafting.

Aged↗

PubMed1998

Protective effects of FK506 against glutamate-induced neurotoxicity in retinal cell culture.

PURPOSE: To examine the effects of FK506 on glutamate neurotoxicity in cultured retinal neurons. METHODS: Experiments were performed with primary retinal cultures obtained from 17- to 19-day-old rat fetuses. To assess the effects of FK506 and other drugs on glutamate neurotoxicity, cultures were treated with a drug beginning 10 minutes before application of glutamate and continuing during the subsequent 10 minutes of glutamate exposure. The treated cells were then incubated for 1 hour in a drug-free and glutamate-free medium. After a 1-hour incubation, cell viability was quantitatively measured by the trypan blue exclusion method. RESULTS: Brief exposure to glutamate markedly decreased cell viability. FK506 protected against glutamate neurotoxicity in a dose-dependent manner. Rapamycin is a competitive inhibitor of FK506 that binds FK506 binding protein. Simultaneous application of rapamycin and FK506 negated the protective effects of FK506. Cyclosporin A, which binds and inhibits calcineurin, mimicked the protective effects of FK506. Treatment with FK506 did not affect the intracellular maximum Ca2+ concentration induced by glutamate application. Although FK506 exhibited protective action against Ca2+ ionophore-induced neurotoxicity, it had no effect on nitric oxide-induced neurotoxicity. Treatment with FK506 reduced the activity of nitric oxide synthase (NOS). CONCLUSION: FK506 protected against glutamate neurotoxicity by inhibiting NOS activity in cultured retinal neurons.

Animals↗

PubMed1998

[Vesico-vaginal fistula with a giant vesico-vaginal stone: a case report].

The patient, a 73-year-old woman, had undergone hysterectomy and irradiation therapy 26 years ago. On September 4, 1997, the patient was referred to our hospital, and presented with low grade fever and lower abdominal dull pain of a one-month duration. Radiologic and vaginal examinations revealed bilateral hydronephrosis and a giant stone lying down between the bladder and vagina. Vaginal incontinence showed the presence of the vesico-vaginal fistula. She underwent bilateral ureterocutaneostomy and cystolithotomy. A giant vesico-vaginal stone was removed by using a hammer and chisel. It weighed 180 g. The stone was composed of calcium phosphate and magnesium ammonium phosphate. Persistent infection of the bladder and the vagina may have been a possible etiological factor of the vesico-vaginal stone formation. Three weeks after the operation, bilateral hydronephrosis was improved.

Aged↗

PubMed1998

[An emergent coronary artery bypass grafting to total occlusion of all three coronary arteries in a patient with severe hyperbilirubinemia].

A 69-year-old man was transferred to our hospital because of chest pain and dyspnea. He had been very ill due to acute hepatitis and hyperbilirubinemia. Coronary angiography showed total occlusion of all three coronary arteries. An emergent coronary artery bypass grafting was successfully performed after insertion of IABP. Even though total bilirubin levels rose to 20.5 mg/dl, it gradually decreased without plasmapheresis. He had no hepatic failure and was discharged on foot on the 24th postoperative days.

Cardiac Surgical Procedures↗

PubMed1998

[Accumulation of a photosensitizer ATX-S 10 Na (II) to experimental corneal neovascularization].

In order to determine the most appropriate time point for laser irradiation in photodynamic therapy with a new photosensitizer, ATX-S 10 Na (II), which produces selective occlusion of new vessels, we investigated the time course of plasma levels of ATX-S 10 Na (II) after intravenous administration and degree of dye accumulation in the corneal neovascularization in rabbit eyes. Plasma ATX-S 10 Na (II) concentration decreased rapidly after injection and become virtually undetectable at 24 h, indicating rapid excretion from the body. Nitrogen-pulsed laser spectrofluorometry demonstrated that the amount of ATX-S 10 Na (II) in new corneal vessels increased and reached a maximal level 2 to 4 hours after dye injection. Under a fluorescence microscope, ATX-S 10 Na (II) was localized in the wall new corneal vessels and in extravascular tissue 2 to 4 hours after dye injection. These results indicate that the appropriate time for laser irradiation in selective PDT is between 2 and 4 hours after dye injection, when a larger amount of dye is accumulated in neovasculature tissue compared to normal tissue.

Animals↗

PubMed1998

[An emergent surgical treatment of recurrent Stanford type A thrombosed aortic dissection].

A 71-year-old male was admitted to our hospital with a chief complaint of back pain. Chest CT scan showed so-called Stanford type A thrombosed aortic dissection. Aortography revealed no ulcer like projection. At first, conservative treatment was carried out. But about two hours later, he had another back pain. Repeat chest CT scan demonstrated an enlarged dissecting lumen, necessitating emergent graft replacement. Postoperative course was uneventful and he was discharged on the 33rd postoperative days.

Aged↗

PubMed1998

[Pulmonary edema associated with the Chinese medicine shosaikoto].

A 45-year-old Japanese woman presented with a high fever, a nonproductive coughing, and severe dyspnea, and was admitted to another hospital. During the week prior to hospitalization, she had been given Shosaikoto for treatment of liver dysfunction of unknown etiology. Mycoplasma pneumonitis was initially suspected, so she was treated with antibiotics (clindamycin and minocycline) and received oxygen therapy. Pulmonary insufficiency worsened rapidly, and she was transferred to our hospital. On admission, a chest roentgenogram revealed bilateral alveolar infiltrates predominantly in the medial lung fields. Furosemide and high-dose methylprednisolone were immediately administered, but hypoxemia increased. When the PaO2 was 55.7 Torr while the patient breathed 100% oxygen, mechanical ventilation with positive end-expiratory pressure (PEEP) was started. Arterial blood-gas values improved dramatically, and the chest roentgenogram became clear. Our diagnosis of noncardiogenic pulmonary edema is based on the chest-roentgenographic findings, infiltration of inflammatory cells as seen in two lung-biopsy specimens and bronchoalveolar lavage fluid, the lack of findings of heart failure on physical examination and electrocardiography, and the good clinical response to PEEP. A positive lymphocyte stimulation test in response to Shosaikoto implicated this non-traditional herbal medicine as an etiologic factor in the non-cardiogenic pulmonary edema. Shosaikoto has been identified as the cause of interstitial pneumonia or eosinophilic pneumonia, but pulmonary edema associated with Shosaikoto has not been previously described. This case suggests that methylprednisolone treatment may be insufficient for Shosaikoto-induced pulmonary edema, and that mechanical ventilation with PEEP is very effective.

Drugs, Chinese Herbal↗

PubMed1997

Developmental changes in distribution patterns of phencyclidine-induced c-Fos in rat forebrain.

In the forebrain of 56-day-old rats, histochemical studies revealed that the subcutaneous injection of a psychotomimetic phencyclidine (PCP; 1 and 10 mg/kg) induced a dose-related and dense nuclear c-Fos-like immunoreactivity in the pyriform cortex, layers IV-VI of the neocortex and septum, but a sparse c-Fos immunostaining in the olfactory tubercle and mid-lateral striatum. Infant rats at postnatal day 8 expressed much fewer and more confined c-Fos-positive cells in the neocortex than young adult rats following PCP injection. However, a similar expression pattern of PCP-induced c-Fos was observed in the pyriform cortex, mid-lateral striatum, olfactory tubercle and septum between the infant and adult periods. These developmental changes in the regional distribution of a neuronal activity marker, c-Fos, suggest that neuronal populations involved in PCP-induced abnormal behavior are influenced by postnatal development, at least, in the neocortex.

Animals↗

PubMed1997

Effects of chondroitinase ABC and chymopapain on spinal motion segment biomechanics. An in vivo biomechanical, radiologic, and histologic canine study.

STUDY DESIGN: The biomechanical effects of chondroitinase ABC and chymopapain related to spinal segmental instability were investigated using a canine model, as well by as radiologic and histologic analyses. OBJECTIVES: To evaluate the biomechanical, radiologic, and histologic affects on the lumber intervertebral disc of chondroitinase ABC compared with chymopapain. SUMMARY OF BACKGROUND DATA: No study on the biomechanical effects of chondroitinase ABC has been reported. METHODS: Forty-eight lumbar intervertebral discs in eight beagles were randomly assigned to three groups and received one of three materials: chondroitinase ABC, chymopapain, or buffered saline, using a lateral percutaneous procedure. One week after injection, the animals were killed and the lumbar spinal motion segments were removed. Spinal segmental instability after chemonucleolysis was evaluated in spinal motion segments without posterior elements. Radiologic and histologic changes were also investigated. RESULTS: Spinal segmental instability and disc space narrowing were more greater in the chymopapain group than in the chondroitinase ABC group. Destruction of nucleus and anulus proteoglycans, indicated by loss of safranin-O staining, was less intense in chondroitinase ABC-injected discs. CONCLUSIONS: Chondroitinase ABC results in less spinal segmental instability, disc space narrowing, and destruction of proteoglycans in intervertebral disc matrix than chymopapain.

Animals↗

PubMed1997

Pedicle screw fixation for nontraumatic lesions of the cervical spine.

STUDY DESIGN: This retrospective study was conducted to analyze the clinical results in 45 patients with nontraumatic lesions of the cervical spine treated by pedicle screw fixation. OBJECTIVES: To evaluate the effectiveness of pedicle screw fixation in reconstructive surgery for nontraumatic cervical spinal disorders. SUMMARY OF BACKGROUND DATA: Pedicle screw fixation for hangman's fracture of the axis and traumatic lesions of the middle and lower cervical spine has been reported; however, there have been no reports on pedicle screw fixation for nontraumatic lesions of the cervical spine. METHODS: Forty-five patients with nontraumatic lesions of the cervical spine underwent reconstructive surgery including pedicle screw fixation and fusion. Five patients underwent occipitocervical fixation for the lesion of the upper cervical spine, and one patient underwent separate occipitocervical fixation and cervicothoracic fixation. Cervical or cervicothoracic fixation was performed in 39 patients. Twenty-six of these patients underwent simultaneous laminectomy or laminoplasty. Supplemental anterior surgery was conducted for 15 patients. RESULTS: Solid fusion was obtained in all patients except eight with metastatic vertebral tumors who did not receive bone graft. Correction of kyphosis was adequate. There were no neurovascular complications, except one case of transient radiculopathy caused by screw threads. CONCLUSIONS: Pedicle screw fixation is a useful procedure for posterior reconstruction of the cervical spine. This procedure does not require the lamina for stabilization, and should be especially valuable for simultaneous posterior decompression and fusion. The risk to neurovascular structures, however, cannot be completely eliminated.

Adult↗

PubMed1997

Homogeneity of Borrelia japonica and heterogeneity of Borrelia afzelii and 'Borrelia tanukii' isolated in Japan, determined from ospC gene sequences.

Borrelia afzelii, B. japonica, and 'B. tanukii' isolated from various sources and geographical origins in Japan were characterized by restriction fragment length polymorphism (RFLP) analysis and sequencing analysis of the outer surface protein C (OspC) amplicon. B. afzelii and 'B. tanukii' generated variable RFLP patterns and differences in ospC gene sequence were confirmed. In contrast, 26 isolates of B. japonica generated one OspC RFLP type, and sequence similarity between B. japonica ranged from 96.4 to 99.7%. These finding suggests that B. japonica is unique in comparison with other members of B. burgdorferi sensu lato species with respect to homogeneity of the ospC gene.

Animals↗