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T Kanazawa

Publications and source records attributed to T Kanazawa.

At least 37 records · Page 2Linked to original sources
PubMed2001

Leupeptin-induced appearance of partial fragment of betaine homocysteine methyltransferase during autophagic maturation in rat hepatocytes.

A cytosolic enzyme, betaine homocysteine methyltransferase (BHMT), and its partial fragments were discovered as autolysosomal membrane proteins from rat liver in the presence of leupeptin [Ueno et al. (1999) J. Biol. Chem. 274, 15222-15229]. The present study was undertaken to further characterize the transport and processing of BHMT from cytosol to autolysosome and to test if the fragment can be used as an in vitro probe for the maturation step of macroautophagy. Upon subcellular fractionation, BHMT (p44) was found in all fractions, while its 32-kDa fragment (p32) was found only in the mitochondrial-lysosomal (ML) fraction. Incubation of isolated hepatocytes with leupeptin induced time-dependent accumulation of p32 in the ML fraction from 30 to 90 min after the start of incubation. However, chloroquine completely inhibited the appearance of p32, indicating that the processing from p44 to p32 is lysosomal. Incubation with Bafilomycin A(1), a vacuolar H(+)-ATPase inhibitor, together with leupeptin, led to linear accumulation of p44, but not of p32. The p44 accumulation rate was calculated to be 4.9%/h, which was comparable to autophagic sequestration rate. The distribution of p44 within the ML fraction turned out to be dual, i.e., the membrane-surface attached and luminal/sedimentable forms. Amino acids and 3-methyladenine, both of which specifically suppress macroautophagy, inhibited the accumulation of p32 as well as of p44. Finally, energy-dependent appearance of p32 was demonstrated during incubation of postnucler supernatant fractions, making it possible to establish an in vitro assay system. All the results strongly support the idea that BHMT is taken up and degraded to p32 through the macroautophagic pathway, and that p32 could be a novel probe for the maturation of macroautophagy.

Animals↗
PubMed2001

Haemangiopericytoma of infratemporal fossa.

Haemangiopericytomas (HPCs) are rare vascular tumours that commonly involve the soft tissues of the trunk and lower extremities. In the head and neck, the most common sites are the nasal cavity and the paranasal sinuses, and unusually, the orbital region, the parotid gland, and the neck. We report a patient with HPC that originated in the infratemporal fossa and involved the pterygopalatine and the middle cranial fossae, apparently the first such case to be reported. Although the patient has undergone resection on three separate occasions, the tumour recurred. We then performed an extended resection using the infratemporal fossa approach type D. The patient has shown no recurrence in the past five years. Although histopathologic confirmation of this malignancy may be difficult, extensive resection remains the most effective treatment in such cases.

Adult↗
PubMed2001

The state of the articular cartilage at the time of surgery as an indication for rotational acetabular osteotomy.

We have studied whether the state of the articular cartilage at the time of rotational acetabular osteotomy for dysplasia of the hip affects the outcome 2 to 5.5 years after surgery. Arthroscopy in 57 patients (59 joints) at the time of the operation showed grade-0 changes in seven, grade-1 in nine, grade-2 in 17, grade-3 in 14 and grade-4 in 12 joints, according to the classification of Outerbridge. There was radiological evidence of the progression of arthritis in four joints which were classified at arthroscopy as grade 4. Stepwise regression analysis showed that damage to acetabular or femoral articular cartilage significantly affected the progression of arthritis. We conclude that the short-term results of successful rotational acetabular osteotomy for dysplasia are affected by the state of the articular cartilage.

Acetabulum↗
PubMed2001

Chemiluminescence of hemoglobin and identification of related compounds with the hemoglobin chemiluminescence in plasma.

A low level of chemiluminescence by hemoglobin (Hb) was detected in the reaction with H2O2 and hydrogen donors such as gallic acid and catechins. The photon intensity was affected by the ferric state of Hb (methemoglobin > oxyhemoglobin), and was roughly correlated with the radical-scavenging potential of catechins. We hypothesized the reversible activation reaction of Hb as the chemiluminescence mechanism of the H2O2/gallic acid/Hb system. It is indicated that the oxidized-Hb (Hb-OOH) formation was a chemiluminescence-rate-determining step and one-electron reduction by a hydrogen donor of the compound-I-type intermediate ([.XFeIV] = O) proved a chemiluminescence-specificity-determining step. Spectral analysis showed that the photon emission from the H2O2/gallic acid/Hb system was produced without singlet oxygen generation. The concentration dependence of photon intensity suggests a high consumption ratio of H2O2 leading to protection from H2O2 toxicity. Albumin was defined as a hydrogen donor by the isolation of chemiluminescent substance in plasma using this chemiluminescence system.

Catechin↗
PubMed2001

[Exchange transfusions in sepsis after the pediatric open heart surgery].

We experienced 2 cases of septic children after open heart surgery. Both of them recovered by using exchange blood transfusion technique. We use irradiated and dialysed fresh blood for exchange blood transfusion. After this procedure, they recovered from sepsis, as the datas improving, white blood cell reduced from 19,700 +/- 3,710 to 8,200 +/- 2,360, CRP reduced from 5.46 +/- 1.65 to 1.89 +/- 0.70, T-Bil reduced from 7.61 +/- 2.66 to 3.02 +/- 0.89, and BUN reduced from 525.92 +/- 6.64 to 19.76 +/- 5.34. Furthermore, blood pressure and urine volume were stable between exchange blood transfusion, although after open heart surgery. Therefore this procedure has benefits for the compromised, septic patients, performed open heart surgery, because of its stability of the circulating circumstances. And using the irradiated and dialysed fresh blood provides stable condition eventhough under high dose catecholamine use.

Anti-Bacterial Agents↗
PubMed2001

Comparison of the antigenicity of protoscoleces and microvesicles of Echinococcus multilocularis prepared from rats.

Rats are known to be relatively resistant to infection with Echinococcus multilocularis. However, when rats are inoculated with the parasite tissues, E. multilocularis proliferates slowly at first but after 6 months the cysts increase in size considerably and contain large numbers of protoscoleces. As rats survive for 18 months or longer, approximately 100 ml of packed protoscoleces can be produced from each rat. A comparison of the antigenicity of the protoscoleces and microvesicles by immunoblot methods showed that both Em18 and Em16 are shared components between both protoscoleces and microvesicles, although the latter have some additional antigenic components. In antigens prepared from protoscoleces, the banding patterns around Em18 were much simpler than those from microvesicles. Therefore, for serodiagnosis of E. multilocularis, antigens should be carefully prepared from protoscoleces rather than microvesicles from the rat.

Animals↗
PubMed2000

Combined therapy with conservative surgery, radiotherapy, and regional chemotherapy for maxillary sinus carcinoma.

BACKGROUND: Current goals for the treatment of carcinoma of the maxillary sinus include the preservation of vision, ability to eat, ability to communicate, and appearance as well as cure. METHODS: Seventy-five Japanese patients who presented with maxillary sinus carcinoma between 1979 and 1997 were analyzed retrospectively. There were 48 males and 27 females with a median age of 62 years. The mean follow-up period was 73 months. All patients underwent multimodality therapy including surgery through a sublabial incision, radiotherapy, and regional chemotherapy. The regional lymph nodes were treated only in those patients with cervical lymph node involvement. RESULTS: The 5-year and 10-year overall survival rates were 76% and 66%, respectively. In 65 patients with squamous cell carcinoma, the 5-year and 10-year overall survival rates were 77% and 66%, respectively. All 23 patients with orbital involvement retained the orbital contents and 17 patients demonstrated adequate ocular function. There was no disease recurrence reported among patients with involvement of the foramen rotundum or the foramen ovale, whereas two of the three patients with invasion of the foramen lacerum developed disease recurrence. There were 12 complications in 12 patients, including double vision (4 patients), cataracts (3 patients), trismus (4 patients), and fistula formation (1 patient). CONCLUSIONS: Control of the primary tumor site is important in the curative treatment of patients with maxillary sinus carcinoma. Combined therapy with conservative surgery, radiotherapy, and regional chemotherapy appears to be an effective method for local control and the preservation of ocular function.

Antimetabolites, Antineoplastic↗
PubMed2000

Inhibition of cytokinesis by a lipid metabolite, psychosine.

Although a number of cellular components of cytokinesis have been identified, little is known about the detailed mechanisms underlying this process. Here, we report that the lipid metabolite psychosine (galactosylsphingosine), derived from galactosylceramide, induced formation of multinuclear cells from a variety of nonadherent and adherent cells due to inhibition of cytokinesis. When psychosine was added to the human myelomonocyte cell line U937, which was the most sensitive among the cell lines tested, cleavage furrow formed either incompletely or almost completely. However, abnormal contractile movement was detected in which the cellular contents of one of the hemispheres of the contracting cell were transferred into its counterpart. Finally, the cleavage furrow disappeared and cytokinesis was reversed. Psychosine treatment also induced giant clots of actin filaments in the cells that probably consisted of small vacuoles with filamentous structures, suggesting that psychosine affected actin reorganization. These observations could account for the formation of multinuclear globoid cells in the brains of patients with globoid cell leukodystrophy, a neurological disorder characterized by the accumulation of psychosine due to galactosylceramidase deficiency.

Actins↗
PubMed2000

Pleomorphic adenoma of the pterygopalatine fossa: a case report.

Pleomorphic adenoma (PA) is the most common benign tumor of the major salivary glands. It can also Occur in the minor salivary glands, mainly in the oral cavity, and in other sites in the head and neck region. We present a very rare case of PA in the pterygopalatine fossa. Surgical resection of the tumor was performed via the transmaxillary approach. The patient has experienced neither surgical complications nor recurrence in the past 3 years. This case suggests that a localized benign tumor in the pterygopalatine fossa can be removed safely and efficaciously via a transmaxillary approach.

Adenoma, Pleomorphic↗
PubMed2000

Invasive verrucous carcinoma: a temporal bone histopathology report.

Only nine cases of primary verrucous carcinoma of the temporal bone have been reported in the English literature. We describe histopathologic findings in a 78-year-old man dying of intracranial complications of primary verrucous carcinoma of the external auditory canal. Following autopsy the temporal bone was prepared for light microscopic examination. The temporal bone was serially sectioned horizontally after fixation, decalcification, and embedding, and each 10th section was stained with hematoxylin and eosin and examined by light microscopy. The carcinoma originated from the external auditory canal, infiltrating the mastoid cavity, the middle ear, tissue adjacent to the internal carotid artery, and the posterior cranial fossa, where it invaded the right cerebellum and produced an abscess. The labyrinth and internal auditory canal were not infiltrated. Metastasis to lymph nodes or distant sites was not identified. In the present case, the verrucous carcinoma originating from the external auditory canal extended into the posterior cranial fossa, while it did not invade the membranous labyrinth.

Aged↗
PubMed2000

A novel strategy for the tumor angiogenesis-targeted gene therapy: generation of angiostatin from endogenous plasminogen by protease gene transfer.

When NIH 3T3 fibroblasts were transduced with a retroviral vector containing a cDNA for porcine pancreatic elastase 1 and cultured in the presence of affinity-purified human plasminogen, the exogenously added plasminogen was digested to generate the kringle 1-3 segment known as angiostatin, a potent angiogenesis inhibitor. This was evidenced by immunoblot analysis of the plasminogen digests using a monoclonal antibody specifically reacting with the kringle 1-3 segment, and by efficient inhibition of proliferation of human umbilical vein endothelial cells by the plasminogen digests isolated from the culture medium of 3T3 fibroblasts. However, when Lewis lung carcinoma cells were transduced with the same vector and injected subcutaneously into mice in their back or via the tail vein, their growth at the injection sites or in the lungs was markedly suppressed compared with the growth of similarly treated nontransduced Lewis lung carcinoma cells. Nevertheless, the transduced cells were able to grow as avidly as the control cells in vitro. Assuming that the elastase 1 secreted from the transduced cells is likely to be exempt from rapid inhibition by its physiological inhibitor, alpha1-protease inhibitor, as shown in the inflammatory tissues, the elastase 1 secreted from the tumor cells may effectively digest the plasminogen that is abundantly present in the extravascular spaces and generate the kringle 1-3 segment in the vicinity of implanted tumor cell clusters. Although the selection of more profitable virus vectors and cells to be transduced awaits further studies, such a protease gene transfer strategy may provide us with a new approach to anti-angiogenesis gene therapy for malignant tumors and their metastasis in vivo.

3T3 Cells↗
PubMed2000

Spectral characteristics of hypernasality in maxillectomy patients.

To reveal the acoustic characteristics associated with hypernasality and to ascertain their correlation to the severity of hypernasality, 30 speech samples produced by 15 maxillectomy patients were acoustically analysed with and without an obturator prosthesis in place. The isolated, sustained Japanese vowel /i/ was used as the stimulus for acoustic measurement and perceptual judgment to evaluate the severity of hypernasality. Normalized 1/3-octave spectral analysis demonstrated the spectral characteristics of hypernasality as a rise in amplitude between the first and second formants around the 1 kHz region, and a reduction in amplitude of the frequencies higher than the second formant. High correlation was shown between the perceptual ratings and the predicted values derived from stepwise regression analysis.

Adult↗
PubMed2000

Sectional prosthesis with hollow obturator portion made of thin silicone layer over resin frame.

Magnetically retained sectional obturator prostheses, consisting of a hollow obturator portion made of thin silicone layer over a resin frame and a denture portion, were fabricated to alleviate some of the limitations of silicone materials, and applied to two edentulous patients with maxillectomy defects. The silicone obturator allowed profound engagement of undercuts within the defect, resulting in adequate retention, support and stability of the prostheses for over 3 years. The patients have achieved improvement in speech and mastication without complications, by use of the obturator prostheses.

Acrylic Resins↗
PubMed2000

Purification and cloning of pierisin-2, an apoptosis-inducing protein from the cabbage butterfly, Pieris brassicae.

The cabbage butterfly Pieris rapae contains a strong apoptosis-inducing substance, pierisin, against human cancer cell lines, which is thought to act via ADP-ribosylation. Here we report the purification and cloning of an apoptosis-inducing substance, designated as pierisin-2, from another cabbage butterfly, Pieris brassicae. Pierisin-2 was purified from pupae by sequential chromatography and its cytotoxic and apoptosis-inducing activities to various cancer cells were similar to those of pierisin, designated as pierisin-1, from P. rapae. cDNA cloning of pierisin-2 was performed on the basis of the partial amino-acid sequence. The nucleotide sequence indicated that the cDNA encodes an 850-amino-acid protein with a calculated molecular mass of 97 986. The deduced amino-acid sequence of pierisin-2 was 91% identical with that of pierisin-1. In vitro expressed protein in the reticulocyte lysate exhibited apoptosis-inducing activities against human gastric carcinoma TMK-1 and cervical carcinoma HeLa cells, similar to the purified native pierisin-2 from the pupae. Pierisin-2 shows regional sequence similarities with certain ADP-ribosylating toxins such as the A-subunit of cholera toxin. The results from site-directed mutagenesis at Glu165, a conserved residue among ADP-ribosylating enzymes necessary for NAD binding, and from experiments with ADP-ribosylating enzyme inhibitors suggested that pierisin-2 could be considered as an ADP-ribosylating toxin like pierisin-1.

ADP Ribose Transferases↗
PubMed2000

Labyrinthine involvement and multiple perforations of the tympanic membrane in acute otitis media due to group A streptococci.

We present here three cases of acute otitis media caused by a virulent group A streptococcal infection that rapidly led to deterioration in hearing. Two of the three cases presented with severe sensorineural and mixed hearing loss with multiple tympanic membrane perforations, and the third presented with severe bilateral sensorineural hearing loss following acute otitis media involving group A streptococci. All patients were treated with systemic (piperacillin) and topical antibiotics (ofloxacin ear drops): one patient also received a systemic steroid (betamethasone). Deafness persisted in one patient but in the other two, hearing gradually recovered. Severe cytotoxicity was considered to have occurred in all patients, resulting in multiple perforations of the tympanic membrane and necrosis in the middle ear.

Adult↗
PubMed2000

An anomalous case of the hepato-spleno-mesenteric and the gastro-phrenic trunks independently arising from the abdominal aorta.

This report describes an arterial anomaly case in the celiaco-mesenteric region, which was encountered in a Japanese male cadaver in the dissecting room at Kurume University School of Medicine in 1999. In this case, the usual celiac trunk was not identified, and the hepato-spleno-mesenteric and the gastro-phrenic trunks were independently arising from the abdominal aorta. In addition, the common hepatic artery divided into the left hepatic, the right hepatic, and the gastroduodenal arteries simultaneously, then, the accessory gastric artery arose from the left hepatic artery. This type of arteral anomaly belongs to the Type III of Adachi's classification and the Type II of Morita's classification.

Aged↗
PubMed2000

Two anomalous cases of the hepato-mesenteric and the gastro-splenic trunks independently arising from the abdominal aorta.

This report describes two arterial anomaly cases in the celiaco-mesenteric region, which were encountered in two Japanese male cadavers in the dissecting room at Kurume University School of Medicine in 1999. In these cases, the usual celiac trunks were not identified, and the hepato-mesenteric and the gastro-splenic trunks were independently arising from the abdominal aorta. Moreover, in the first case, the common hepatic artery passed ventral side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type V of Adachi's classification and the Type IV' of Morita's classification. In the second case, the common hepatic artery passed dorsal side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type VI of Adachi's classification and the Type IV' of Morita's classification.

Aged↗