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Biomedical subjects

T Kato

Publications and source records attributed to T Kato.

At least 73 records · Page 4Linked to original sources

Movement of the side hole occurring in a port-catheter system percutaneously implanted for hepatic arterial infusion chemotherapy.

The authors report a case in which catheter-related difficulties occurred with a port-catheter system implanted to perform repeated hepatic arterial infusion chemotherapy for advanced hepatocellular carcinomas. The port-catheter system had been percutaneously implanted with the catheter tip fixation method, and a side hole had been created in the indwelling catheter for placement in the common hepatic artery. Four months after port-catheter placement, however, the indwelling catheter became bent at the location of the side hole in the proper hepatic artery. Subsequently, the side hole moved into the left hepatic artery, resulting in a lack of distribution of chemotherapeutic agents to the tumours in the segments of the liver supplied by the right hepatic artery. This situation was easily corrected with a simple interventional radiological method so that hepatic arterial infusion chemotherapy could be resumed with sufficient distribution over the entire liver. To our knowledge, such a problem involving a port-catheter system implanted with the catheter tip fixation method and its management thereafter has not been reported in the published literature.

Aged↗

Decreased prothrombotic effects of pegylated recombinant human megakaryocyte growth and development factor in thrombocytopenic state in a rat thrombosis model.

Previous in vitro studies demonstrated that thrombopoietin (TPO) acts on platelets to activate a variety of intracellular signaling pathways and to enhance platelet sensitivity to multiple agonists. Little is known, however, about whether TPO exerts prothrombotic effects in vivo. The aim of this study was to examine the effects of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF), a pegylated N-terminal domain of human TPO, in a rat model of venous thrombosis. A microthrombus was photochemically induced on the vessel wall of a mesenteric venule, but the vessel was not occluded by it. A single intravenous injection of PEG-rHuMGDF (3 microg kg(-1)) after the thrombus generation into normal rats enhanced the thrombus size, resulting in transient thrombotic occlusion in the majority of rats. Stimulatory effects on thrombus growth were also observed following administration of glycosylated recombinant human full-length TPO (6 microg kg(-1)). In rats rendered thrombocytopenic by total body irradiation, however, PEG-rHuMGDF, even at 300 microg kg(-1), did not induce a significant increase in thrombus size or thrombotic occlusion. Platelets from thrombocytopenic rats had decreased surface levels of c-Mpl and decreased sensitivity to PEG-rHuMGDF in an in vitro aggregation response. Thus, decreased prothrombotic effects of PEG-rHuMGDF in thrombocytopenic rats might be the result not only of low platelet counts but also of decreased platelet reactivity to PEG-rHuMGDF. These results indicate that PEG-rHuMGDF has little effect on venous thrombus formation in thrombocytopenic states associated with high endogenous TPO levels.

Animals↗

Treatment of a Gilbert's syndrome patient with irinotecan, leucovorin and 5-fluorouracil.

The patient was an elderly male who had radical surgery for sigmoid cancer in 2001. Owing to metastasis of his cancer to the left supraclavicular lymph nodes in 2002, the patient was admitted to our hospital for systemic chemotherapy. We started treatment with irinotecan, leucovorin, 5-fluorouracil (IFL). After administering 100 mg/m2 of irinotecan, 250 mg/m2 leucovorin and 600 mg/m2 5-fluorouracil to the patient on day 1, grade 3 leukopenia developed rapidly and grade 4 thrombocytopenia was observed on day 5. We excluded irinotecan from the medication and continued the administration of 5-fluorouracil and leucovorin, but his tumors had not been reduced sufficiently. Based on some examination results, we assumed that the patient had Gilbert's syndrome and that the severe side effects that occurred were due to prolongation of SN38 metabolism. We again administered irinotecan but at reduced dose (25 mg/m2). Four courses of this modified IFL were administered safely and the response was favorable.

Aged↗

Cyclophosphamide and low-dose prednisolone in idiopathic pulmonary fibrosis and fibrosing nonspecific interstitial pneumonia.

The present study compared the efficacy of cyclophosphamide combined with low-dose prednisolone in the treatment of idiopathic pulmonary fibrosis (IPF) with efficacy in idiopathic fibrosing nonspecific interstitial pneumonia fibrosing (NSIP). A total of 27 patients with IPF and 12 patients with fibrosing NSIP were included in this study. All patients had undergone surgical lung biopsy. The diagnoses were made based on clinical, radiological and pathological findings. All patients were treated with intermittent pulse therapy with methylprednisolone for 4 weeks, followed by cyclophosphamide with low-dose prednisolone. According to pulmonary function tests, four of 27 patients with IPF had improved, 22 remained unchanged, and one had worsened at the completion of pulse therapy. After 1 yr of combination therapy, four of 27 patients had improved, 14 remained unchanged, and nine had worsened. After pulse therapy, four of 12 patients with fibrosing NSIP had improved, and eight remained unchanged. After 1 yr of combination therapy, eight of 12 patients had improved, four remained unchanged, and none had worsened. Median survival of IPF patients was 4.1 yrs, which is significantly worse than that of fibrosing NSIP patients. In conclusion, patients with fibrosing nonspecific interstitial pneumonia had a more favourable response to combination therapy and a better survival than those with idiopathic pulmonary fibrosis.

Anti-Inflammatory Agents↗

Spontaneous healing of chyle leakage after lymphangiography.

We report a 34-year-old man with the complication of chylous ascites after retroperitoneal lymphadenectomy that was refractory to various conservative therapies. Because surgical treatment for chylous ascites was considered, lymphangiography was performed to identify the area of leakage of chyle, after which the chylous ascites spontaneously healed.

Adult↗

Galectin-1 as a potential therapeutic agent for amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects almost selectively motor neurons in the central nervous system. Most ALS patients die within five years of onset. One of the neuropathological features of ALS is an "axonal spheroid," a large swelling of a motor axon within the anterior horn of the spinal cord; this abnormal structure seems to be related to the pathogenesis of motor neuron degeneration in ALS. In 2001, using biochemical and immunohistochemical methods, we found an accumulation of galectin-1 in ALS spheroids. By immuno-electron microscopy, the galectin-1 accumulated in the spheroids was observed to be closely associated with neurofilaments. Furthermore, we observed a marked depletion of galectin-1 in the skin of ALS patients; another abnormality frequently observed in ALS. These findings, therefore, suggest that galectin-1 may be involved in the pathogenesis of ALS. It is known that an oxidized form of galectin-1 promotes axonal regeneration; however, it is not known whether oxidized galectin-1 has a beneficial or an adverse effect on the pathophysiology of ALS. To examine this issue, we administered oxidized galectin-1 to transgenic mice with H46R mutant SOD1, an ALS model mouse. The results showed that the administration of oxidized galectin-1 improved the motor activity, delayed the onset of symptoms, and prolonged the survival of the galectin-1-treated mice. Furthermore, the number of remaining motor neurons in the spinal cord was more preserved in the galectin-1-treated mice than in the non-treated mice. We conclude that galectin-1 could be a candidate agent for the treatment of ALS.

Amino Acid Sequence↗

[Primary neurogenous sarcoma of the lung; report of a case].

We report a case of a 27-year-old woman with primary neurogenous sarcoma of the lung. She had no symptoms but an abnormal shadow of the right lower lung field on the chest X-ray. Chest computed tomography (CT) revealed a well defined round mass, 20 mm in maximum diameter, at the right S9. Pathological study of the specimen obtained by CT-guided percutaneous needle biopsy showed undefferentiated carcinoma. Positron emission tomography (PET) disclosed intensely increased uptake of fluoro-2-deoxy-D-glucose (FDG) at the lung lesion without other abnormal uptakes. The patient underwent right lower lobectomy of the lung and mediastinal lymph nodes dissection. Results from immunohistological study yielded a definitive diagnosis of neurogenous sarcoma. Postoperative course was uneventful, and there has been no evidence of recurrence and metastasis for more than a year after the surgery. Reported cases of primary neurogenous sarcoma of the lung are reviewed.

Adult↗

[Surgical treatment of lung cancer in octagenarian patient].

Because average life span of Japanese is getting longer, we sometimes meet elder lung cancer patients of over 80. They often have many complications, so we are worried about how to treat them. Recently we met 8 elder patients with lung cancer, and we performed surgical operation for them. Six patients performed partial lung resection or lobectomy had no complications after operation. But 2 patients with respiratory disorder who performed lobectomy and chest wall resection had some complications after operation. In such patients, careful postoperative management is needed, and continuous positive airway pressure (CPAP) ventilation with pressure support (PS) may be useful to prevent respiratory complications.

Age Factors↗

Histatin 5 inhibits apoptosis in human gingival fibroblasts induced by porphyromonas gingivalis cell-surface polysaccharide.

The cell-surface components of Porphyromonas gingivalis have various biological activities. In the present study, we investigated the virulence of several cell-surface components prepared from P. gingivalis in human gingival fibroblasts (HGF). Furthermore the preventive effect of salivary protein histatin 5 was investigated. P. gingivalis polysaccharide (PS) significantly inhibited HGF proliferation, but lipopolysaccharide and outer-membrane protein did not. By using ELISA analysis, DNA fragmentation in HGFs was observed intracellularly when treated with the PS. These results suggest that the PS of P. gingivalis can induce apoptosis in HGF. Pretreatment of PS with histatin 5 restrained the inhibitory effect of PS on HGF proliferation. Histatin 5 also suppressed the apoptotic cell death in HGF induced by PS stimulation. The present study suggests that the PS of P. gingivalis can modulate the cell population in periodontal tissue, causing periodontitis by inducing HGF cell death through apoptosis. Also histatin 5 can inhibit the PS activity and may play an important part in the regulation of inflammatory periodontal diseases.

Apoptosis↗

The resurgence of Shamonda virus, an African Simbu group virus of the genus Orthobunyavirus, in Japan.

Six virus isolations were made from Culicoides biting midges and blood samples of sentinel cattle in Kagoshima and Miyazaki Prefectures, the southern part of Japan, in 2002. Serological and genetical tests identified these viruses as isolates of Shamonda virus (SHAV), which belongs to the Simbu group of the genus Orthobunyavirus of the family Bunyaviridae. Initially, SHAV was isolated from cattle and Culicoides biting midges in Nigeria in the 1960s, and its presence has not been reported until this study. The present results indicate a wider distribution of SHAV than previously assumed.

Animals↗

Evidence for an oscillatory signature in atmospheric neutrino oscillations.

Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3) 0.90 at 90% confidence level.

Journal Article↗

Limits on the neutrino magnetic moment using 1496 days of Super-Kamiokande-I solar neutrino data.

A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)</=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)</=(1.1x10(-10))micro(B) at 90% C.L. was obtained.

Journal Article↗

Lateral and medial medullary infarction: a comparative analysis of 214 patients.

BACKGROUND AND PURPOSE: No large-scale study has ever compared the clinical and radiological features of lateral medullary infarction (LMI) and medial medullary infarction (MMI). The aim of this study was to investigate them through the use of cooperatively collected cases. METHODS: Medical information on all patients from 1996 to 2000 with medullary infarction (MI) proven by brain MR images at 35 stroke centers in the Tohoku district, Japan, was collected, and their clinical and radiological features were analyzed. RESULTS: A total of 214 cases of MI were registered. They included 167 cases (78%) of LMI, 41 (19%) of MMI, and 6 (3%) of LMI plus MMI. The mean age of onset and the male-to-female ratio were 60.7 years and 2.7:1 in LMI and 65.0 years and 3.6:1 in MMI, respectively. The middle medulla was most frequently affected in LMI, and the upper medulla was most frequently affected in MMI. Dissection of the vertebral artery was observed in 29% of LMI and 21% of MMI. Prognosis, assessed by the Barthel Index, was favorable in both LMI and MMI. Diabetes mellitus was more frequently associated with MMI than with LMI. CONCLUSIONS: The present study surveyed a large number of MI cases and revealed that (1) the mean age of onset of MMI is higher than that of LMI, (2) the dissection of the vertebral artery is an important cause not only of LMI but also of MMI, and (3) diabetes mellitus is frequently associated with MMI.

Age Factors↗

The emergence in Japan of Sathuperi virus, a tropical Simbu serogroup virus of the genus Orthobunyavirus.

In 1999, two viruses were isolated from blood samples of sentinel cattle in the Western part of Japan. The physiochemical and morphological properties of these viruses indicated that they belonged to the family Bunyaviridae. Sequence analysis of the S segment indicates that the two viruses are closely related to Sathuperi virus (SATV). The N-terminal 168 amino acid of the G2 protein of the M segment was highly homologous with that of SATV (98.2%). Given these results, we conclude that the newly isolated viruses are closest to SATV, which was initially isolated in India and Nigeria over 30 years ago.

Amino Acid Sequence↗

Preoperative probability model for predicting overall survival after resection of pulmonary metastases from colorectal cancer.

BACKGROUND: The aim of this study was identify readily available factors most helpful in predicting survival and to develop a prognostic nomogram for patients with pulmonary metastases from colorectal cancer who are candidates for thoracotomy. METHODS: Pretreatment data on 313 patients with metastases who underwent thoracotomy were analysed. Fourteen preoperative clinical and pathological variables were used to develop a probability model, in which their association with 3-year survival was tested. A nomogram to predict median, 1- and 3-year survival was constructed and validated internally using the concordance index (c-index). The nomogram was then validated with an external data set. RESULTS: Five variables were identified as independent predictors of 3-year survival: prethoracotomy carcinoembryonic antigen level, number of pulmonary tumours, presence of hilar or mediastinal tumour-infiltrated lymph nodes, histology of the primary tumour and presence of extrathoracic disease. The nomogram was well calibrated for predicting 3-year overall survival. The internal validated c-index of the nomogram was 0.72. Applied to another data set, the external validated c-index was 0.66. CONCLUSION: This model has moderate predictive ability to discriminate between patients who are likely to survive after thoracotomy for pulmonary metastases from colorectal cancer.

Adult↗

Use of donor aorta for arterial reconstruction in paediatric liver and multivisceral transplantation.

BACKGROUND: Arterial reconstruction remains the most important technical issue in paediatric transplantation. The arteries of paediatric donors as well as recipients are small and friable. The aim of this study was to assess the use of the donor aorta as a conduit for arterial reconstruction in paediatric liver and multivisceral transplantation. METHODS: Between June 1994 and January 2002, 284 paediatric transplants, including 197 cadaveric liver and multivisceral transplants, were performed in children at this centre. Of these, 41 (20.8 per cent), including nine cadaveric liver transplants and 32 multivisceral transplants, were revascularized by donor aortic reconstruction. Patient demographics, types of donor arterial reconstruction, technical complications and incidence of hepatic artery thrombosis were reviewed. RESULTS: None of the 41 donor aortic reconstructions used in revascularization of paediatric liver and multivisceral transplants thrombosed. There were no bleeding complications and no pseudoaneurysms developed. CONCLUSION: Arterial reconstruction using donor aorta is a useful option with a low incidence of thrombosis in paediatric transplantation.

Aorta↗

Extended sigmoid-shaped free jejunal patch for reconstruction of the oral base and pharynx after total glossectomy with laryngectomy.

The procedure for reconstruction of the extensive defect after total glossectomy with total laryngectomy has not been standardised so far. We have devised a new method in which a free jejunal patch is extended to a sigmoid-shaped form specifically optimised for reconstruction of the defect that consists of the entire floor of the mouth and the antero-lateral walls of the pharyngoesophageal tract. After a jejunal segment of about 40 cm has been longitudinally opened in full length, the proximal quarter is folded parallel to the second quarter, which is then folded parallel to the third quarter in the opposite direction, to be laid out in a S-shaped form. Side-by-side sutures are then placed along each of the folded borders and corrective trimming is done to fit the defect. This widely extended patch replaces the whole oral base, whereas the remaining distal quarter of the patch replaces the antero-lateral walls of the hypopharynx and cervical esophagus. Because of the encouraging functional results with satisfactory restoration of oral alimentation, this procedure is considered to be ideal for the reconstruction of the defect which follows total glossectomy with total laryngectomy.

Adult↗