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Biomedical subjects

T Fukushima

Publications and source records attributed to T Fukushima.

At least 289 records · Page 16Linked to original sources
PubMed1996

Transcytosis of lipid microspheres by human endothelial cells.

Human endothelial cells were cultivated on microporous membranes mimicking the luminal and basal spaces of blood vessels. When fluorescence-labeled lipid microspheres (LM) were added to the upper chambers of the model cultures, confluent monolayers of endothelial cells transported considerable levels of fluorescence to lower chambers. The transport was time dependent and was diminished by the addition of cytochalasin B. The uptake of LM into the endothelial cytoplasm was confirmed by electron microscopy and laser scanning confocal imaging. The amounts of fluorescence in the lower chamber were reduced when the endothelial cell layer was fixed with formaldehyde. These observations suggest that endothelial cells can transport LM by transcytosis. Endothelial cells seem to carry the LM without processing, since only minimal amounts of free fluorescence were detected even after longer cultivation periods. The fluorescence in the lower chambers of cell cultures treated with interleukin 1 beta was 3.7-fold higher than that of untreated cells; interleukin 2 and tumor necrosis factor alpha treatments had no discernible effect on LM transport. The interleukin 1 beta induced increase of transcytosis in endothelial cells would explain why LM preferentially accumulate in inflammatory tissues.

Biological Transport↗
PubMed1996

A single-base mutation in exon 31 converting glycine 852 to arginine in the collagenous domain in an Alport syndrome patient.

In a family with Alport syndrome, molecular analysis of the COL4A5 gene, which encodes the alpha 5(IV) chain of glomerular basement membrane collagen, revealed a GGA-->AGA change in exon 31, resulting in substitution of an arginine for a glycine in position 852 of the polypeptide chain, between interruptions 16 and 17 of the triple-helical collagenous domain. The mutation causes the MaeI restriction sites, and could be easily diagnosed in the family members through restriction analysis. This one point mutation can be expected to interrupt type IV collagen molecules.

Adult↗
PubMed1996

Petroclival meningiomas: surgical experience in 109 cases.

The surgical removal of petroclival meningiomas has historically been associated with a high incidence of morbidity and mortality. The 109 consecutive patients included in the present retrospective study represent a combined series of tumors operated on by the four authors during a period from 1980 to 1992. The series is composed of 40 men and 69 women ranging in age from 25 to 75 years (mean 51 years). Surgical approaches to tumors in this series included simple retromastoid (60 cases), combined supra- and infratentorial petrosal (22), transtemporal (primary transsigmoid retrolabyrinthine, translabyrinthine, or transcochlear (12), subtemporal (11), and frontotemporal transcavernous (eight). Gross-total removal was achieved in 75 patients (69%). Recurrence or progression of disease occurred in 14 patients (13%) over a 6.1-year mean follow-up period, and it was found within the cavernous sinus in 12 of these cases. Four recurrent cases demonstrated histological compatibility with malignant meningioma. Perioperative death occurred in four patients, and there were 56 significant complications in 35 other patients. Review of this series, with the attendant complications, has facilitated the authors' decision-making when considering the risk of gross-total removal in selected patients with asymptomatic cavernous sinus invasion or tumor adherent to the brainstem.

Adult↗
PubMed1996

[Problems encountered with a programmable pressure valve (SOPHY) positioned in the chest wall].

Sixty-eight hydrocephalic patients were treated with a shunt system that incorporated a SOPHY programmable valve. This device is very effective for treating disorders of CSF circulation. However, when the valve is placed on the scalp, it produces artifacts on MR imaging due to its small magnetic rotor, and may cause necrosis of the scalp above it. On the other hand, when it is positioned on the chest, MR artifacts decrease and exchanging the valve devices becomes easier. Therefore, we have positioned the device on the chest. However, some complications were encountered, such as the turning over of the valve in the subcutaneous pocket and the twisting of the shunt tube. Moreover, the shunt tube may stretch due to growth of the neck during development in infantile patients or extension of the neck during exercise. These complications are associated only with subcutaneous placement on the chest, so we conclude that such a valve, if placed on the chest, should be placed in a lower position on the chest, and if MR examination will not be performed in the foreseeable future, we recommend that it be placed on the occipital scalp, especially in infantile patients.

Aged↗
PubMed1996

[K-ras gene mutations in adenomas from familial adenomatous polyposis].

A 18-year-old woman underwent total colectomy for familial adenomatous polyposis. In order to clarify the significance of K-ras mutations in early colorectal carcinogenesis, K-ras mutations were analyzed in multiple adenomas by PCR-SSCP method. A total of 256 adenomas were found throughout the entire colon and rectum, and the distribution was a sparse type. The correlation between K-ras gene and clinicopathological factors was examined in 90 adenomas. There was no correlation among K-ras mutations and anatomical distribution, or morphological classification, but K-ras mutation was more frequent in severe compared with slight atypia. We investigated the correlation between the size of adenoma in the horizontal and vertical directions and K-ras mutation. K-ras mutation was more frequent in the horizontal size greater than 6 mm in diameter, and also more frequent in vertical size greater than 20 mm in height. It was concluded that the adenomas detecting K-ras mutations might have proliferating potential, and would be applied to determine polypectomy.

Adenoma↗
PubMed1996

Treatment of scalp arteriovenous malformation.

We report seven patients with scalp arteriovenous malformations, including two patients with lesions > 10 cm in diameter, who were successfully treated. The principal complaint of each patient was a deforming mass. Each of four patients had a history of blunt traumatic injury. The lesions, each consisting of the nidus, feeders, and draining veins, evolved in all patients. The nidus consisted of fistulae, which exhibited various angioarchitectures as revealed by angiography. A hemangiomatous component was histologically recognized in one patient. In five patients, in whom the lesions were relatively small and whose nidi included only large fistulae, the malformations were remedied by surgical intervention alone or were cured with embolization alone using liquid adhesives. In the two patients with lesions > 10 cm, the nidi consisted of numerous large fistulae and plexiform fistulae in one patient and plexiform fistulae and a hemangiomatous component in the other patient. These patients were treated with a combination of transarterial embolization and surgical intervention. Preoperative embolization greatly reduced blood loss during resection. Total excision and scalp reconstruction using a soft tissue expander were performed in both patients. The cosmetic results were excellent in all of the patients, and no recurrence has been recognized during the follow-up period, which ranges from 31 to 99 months. The treatment of scalp arteriovenous malformations should strive to improve deforming features and to attain a permanent cure. Because each nidus includes a variety of anomalous angioarchitectural features, there should be different means and a combination of treatments for each patient. Embolization alone could be adequate treatment in relatively small lesions, the nidi of which consist only of several large fistulae. For malformations with more extensive, large fistulae or with anomalous components other than large fistulae, a combined endovascular and surgical approach and scalp reconstruction seems to be the best treatment.

Adult↗
PubMed1996

Surface and superficial surgical anatomy of the posterolateral cranial base: significance for surgical planning and approach.

We have performed an anatomic study, 15 using fixed cadaveric preparations, with the goal of identifying surface landmarks that will reliably locate the underlying transverse and sigmoid sinus complex. Simple morphometric relationships were first determined on both sides of each specimen to yield 30 sides measured. The following relationships were determined: 1) zygoma root-asterion, 2) asterion-mastoid tip, 3) zygoma root-suprameatal spine (Henle's spine), 4) asterion-suprameatal spine, 5) mastoid tip-suprameatal spine. The relationship of the asterion to the transverse-sigmoid junction was determined by bone removal. Also, the distances from the asterion to the sigmoid sinus-superior petrosal sinus junction and the superior margin of the transverse sinus were studied. Surface and marks were found to have definitive relationships to underlying anatomic substrates in all specimens studied. The critical relationships that were concluded from this study can be described in terms of two easily identified lines between bony surface structures. A line drawn from the zygoma root to the inion, i.e., the superior nuchal line, reliably located the rostrocaudal level of the transverse sinus in all specimens. Although the asterion did not consistently fall on this line, the transverse-sigmoid junction could reliably be placed at the anteroposterior level of the asterion. Further, a line drawn from the squamosal-parietomastoid suture junction to the mastoid tip reliably defined the axis of the sigmoid sinus through the mastoid. We also found that the junction of the squamosal and parietomastoid sutures lay over the anterior border of the upper curve of the sigmoid sinus. The anterior portion of the supramastoid crest correlated with the level of the middle fossa. These surface relationships all have significance for posterolateral approaches to the cranial base. Since performing this study, these relationships have been found reliable for operative planning in our clinical cases.

Cephalometry↗
PubMed1996

Superior cytotoxic potency of mitoxantrone in interaction with DNA: comparison with that of daunorubicin.

The mechanism of action of the anthraquinone antileukemic drug mitoxantrone (MIT) was investigated and compared with that of daunorubicin (DNR) with emphasis on the interaction with DNA to clarify the more potent cytotoxic activity of MIT than DNR in human leukemia cells. MIT showed similar characteristics to those of the anthracyclines such as DNR in that binding of MIT to DNA was associated with reduced template activity and cleavage of DNA in HL-60 human leukemia cells. However, as compared with DNR, MIT showed an increased number of binding sites on DNA, a lower inhibition constant for DNA polymerization, and a greater DNA cleavage activity. These properties may contribute to its greater potency than that of DNR, with which MIT inhibited the proliferation of HL-60 human leukemia cells.

Antineoplastic Agents↗
PubMed1996

Innovations in surgical approach: lateral cranial base approaches.

The extradural anterior transpetrosal approach possesses several advantages. First, the majority of the dissection is extradural, providing protection to the overlying neural structures. Second, only limited retraction of the temporal lobe is necessary, protecting venous outflow via the vein of Labbe'. Third, transposition of cranial nerves or vascular structures in unnecessary. Fourth, it enjoys natural compatibility with other surgical approaches to enhance exposure of the posterior cavernous sinus and petroclival region. The disadvantages are mostly related to the unfamiliar anatomy. Most surgeons are not accustomed to visualizing petrous apical anatomy from the middle fossa orientation. Therefore, practice of this technique in the cadaver laboratory is a mandatory prerequisite to its performance in the operating room. The cochlea, carotid artery, labyrinth, and cranial nerves five through eight are all at risk during drilling and dissection. When performed properly, this technique provides a solid adjunct to treating complex lesions of the central cranial base.

Cavernous Sinus↗
PubMed1995

Radical formation site of cerebral complex I and Parkinson's disease.

Paraquat was reduced to the paraquat radical via complex I in bovine cerebral mitochondria and accelerated lipid peroxidation. Thirty-kilodalton subunit of complex I was considered to be the radical formation site, because of its marked destruction by the paraquat radical. The lipid peroxidation by the paraquat radical was suppressed not only by superoxide dismutase (SOD) but also by mannitol. The destruction of complex I subunits via lipid peroxidation must have been caused by the hydroxyl radical which was formed from the superoxide radical. The same phenomenon was observed by using 1-methylnicotinamide (MNA), which contains the same partial structure as paraquat in itself and is metabolized from nicotinamide in a living body. We observed NADH oxidation by MNA via cerebral complex I (Km = 26.3 mM), and MNA destroyed some complex I subunits, especially 30-kilodalton protein. Paraquat might be useful for studying the pathogenesis of Parkinson's disease (PD) in vitro, and MNA is expected to be one of the causal substances of PD from the viewpoint of the oxidative stress theory.

Animals↗
PubMed1995

Successful treatment of invasive thoracopulmonary mucormycosis in a patient with acute lymphoblastic leukemia.

BACKGROUND: Pulmonary mucormycosis associated with hematologic malignancy is an uncommon, but important opportunistic fungal pneumonia that is usually a fatal infection. Only a few survivors of pulmonary mucormycosis have been reported. METHODS: A case report of invasive thoracopulmonary mucormycosis during remission-induction therapy for acute lymphoblastic leukemia and a review of the literature are presented. RESULTS: The fungal lesions extended to both lungs, the left ribs, and intercostal muscles. Percutaneous needle biopsy and immunostaining of the fungal hyphae established the diagnosis of thoracopulmonary mucormycosis. The patient was treated with granulocyte-colony stimulating factor (G-CSF) and intravenous amphotericin B for 9 weeks and the lesions in the right lung disappeared. Left pneumonectomy and partial resection of the chest wall were later performed. The left lung was grossly necrotic and contained a large cavity and bronchopulmonary fistula. Thereafter, antileukemic therapy was resumed and completed without recurrence of mucormycosis or leukemia. CONCLUSIONS: In the management of mucormycosis, the addition of G-CSF to the conventional treatment may substantially improve outcome.

Adolescent↗
PubMed1995

Intraductal extension of primary invasive breast carcinoma treated by breast-conservative surgery. Computer graphic three-dimensional reconstruction of the mammary duct-lobular systems.

BACKGROUND: Intraductal tumor extension is a characteristic feature of primary breast carcinoma, and is an important consideration in patients undergoing breast conservative surgery. However, there have been no reports of studies of intraductal extension within the mammary ductal tree. METHODS: Quadrantectomy specimens from 20 patients with primary invasive breast carcinoma were examined by subgross and stereomicroscopic technique to visualize intraductal tumor extension. Serial 2 mm-thick sections were subjected to two-dimensional (2-D) tumor mapping, measuring the distances and angles of extension, and to three-dimensional (3-D) reconstruction of the mammary duct-lobular systems by means of computer graphics. RESULTS: Intraductal tumor extension was found in 16 of 20 specimens (80.0%), extending continuously from the primary invasive carcinoma through the mammary ductal tree. The distances and angles of extension were larger in tumors with microcalcifications, papillotubular invasive ductal carcinoma, 30% or more of intraductal component, and comedo-type intraductal tumor extension. The 3-D reconstructions demonstrated three types of extension; central (11 cases), peripheral (3 cases), and mixed (2 cases). Further, there were some ductal branches anastomosing with different mammary duct-lobular systems at various sites. In one specimen, intraductal tumor extended widely from the primary invasive carcinoma through a branch connecting adjacent mammary duct-lobular systems. CONCLUSIONS: Three-dimensional reconstruction images of intraductal extension of invasive breast carcinomas are presented for the first time to the authors' knowledge. Examples of ductal anastomoses were observed, and should be considered as a risk factor for possible widespread intraductal extension through multiple mammary duct-lobular systems.

Adult↗
PubMed1995

The role of carbon monoxide in lucigenin-dependent chemiluminescence of rat alveolar macrophages.

We have investigated the role of carbon monoxide (CO) in lucigenin-dependent chemiluminescence of alveolar macrophages from rat lungs. CO (10 nM to 1 microM) decreased chemiluminescence of alveolar macrophages in a concentration-dependent fashion. At a concentration of 1 microM, CO significantly increased intracellular cyclic GMP levels from a control value of 175 +/- 25 fmol/2 x 10(6) cells to 431 +/- 49 fmol/2 x 10(6) cells. Pretreatment of alveolar macrophages with NG-monomethyl-L-arginine (100 microM) failed to inhibit CO (1 microM)-induced decreases in chemiluminescence of alveolar macrophages (3.7 +/- 0.7 cpm x 10(3) in the presence of NG-monomethyl-L-arginine and 3.4 +/- 0.6 cpm x 10(3) in the absence of NG-monomethyl-L-arginine) and CO (1 microM)-induced increases in intracellular cyclic GMP levels (452 +/- 65 fmol/2 x 10(6) cells in the presence of NG-monomethyl-L-arginine and 419 +/- 58 fmol/2 x 10(6) cells in the absence of NG-monomethyl-L-arginine). Decreases in chemiluminescence of alveolar macrophages induced by CO (1 microM) were concentration-dependently inhibited by methylene blue (from 0.1 microM to 10 microM). Dibutyryl cyclic GMP (db cyclic GMP) (1 mM) also reduced chemiluminescence of alveolar macrophages (1.5 +/- 0.3 cpm x 10(3) in the presence of db cyclic GMP and 3.6 +/- 0.6 cpm x 10(3) in the absence of db cyclic GMP). In contrast to CO and db cyclic GMP, zinc protoporphyrin-9 (10nM to microM), an inhibitor of heme oxygenase potentiated chemiluminescence of alveolar macrophages in a concentration-dependent fashion.(ABSTRACT TRUNCATED AT 250 WORDS)

Acridines↗
PubMed1995

Seton treatment for perianal Crohn's fistulas.

In this study, we evaluated the efficacy of long-term seton drainage in the management of 13 patients with severe perianal Crohn's fistulas which had proven to be intractable to conventional therapy. After adequate curettage of the fistulous tracts and infected tissue, either a Penrose drain or a fine polyethylene catheter was inserted to encircle the tracts and tied. Patients were followed up for a mean period of 12.1 months. Perianal pain disappeared or improved in all 13 patients, while the body temperature of all 7 with pyrexia dropped to within the normal range. Discharge disappeared or diminished in 77% (10/13) and tenderness disappeared or improved in 77% (10/13). Induration disappeared or improved in 69% (9/13). Overall, good results were achieved in 10 patients, although 3 required redrainage. In one of these patients, a good result was achieved after colostomy was performed for active intestinal disease. Nevertheless, 2 patients did not improve, one of whom required lay-open surgery after seton treatment. In 8 of the 13 patients, some seton drains were able to be removed, and none of the patients experienced any soiling or leakage. Thus, we conclude that seton treatment is worthwhile in the management of perianal Crohn's fistulas as it alleviates the symptoms and simplifies multiple tracts. Moreover, it preserves sphincter function, is less invasive, and can be managed easily.

Adult↗
PubMed1995

Report on the first annual survey of home parenteral nutrition in Japan.

An annual survey of the current national status of home parenteral nutrition (HPN) in Japan was begun in 1991, with a total of 231 registered patients from 142 institutions providing adequate data for evaluation and analysis. HPN was given for an average of 683 +/- 764 days to 93 patients with malignant diseases and 138 with benign disease, including 53 with inflammatory bowel disease and 79 with short bowel syndrome, 107 (46.3%) of whom were successfully rehabilitated. By the end of 1990, 61% of the patients investigated were still on HPN, 7% had already completed HPN, and 26% had died, the deceased accounting for 54% of the patients with malignant diseases and 7% of those with benign diseases. A total of 321 catheters had been used by all 231 patients, the most common being the subcutaneously implanted type, accounting for 33% of all catheters. By the end of 1990, 32% of these 321 catheters were still in place, 18% had been removed on the termination of HPN and 44% had been removed due to complications of total parenteral nutrition, including 20% for catheter fever. Rehospitalization was required in 62% of the patients, the cause being HPN-related in 21% of the total patients. Metabolic complications were experienced by 60% of the patients, but none of these were severe although 6% required hospitalization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗