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Biomedical subjects

K Fukuta

Publications and source records attributed to K Fukuta.

At least 19 recordsLinked to original sources
PubMed1992

Purification and characterization of glycerate kinase from a serine-producing methylotroph, Hyphomicrobium methylovorum GM2.

The glycerate kinase of a serine-producing methylotroph, Hyphomicrobium methylovorum GM2, was purified to complete homogeneity and characterized, the first time for an enzyme from a methylotroph. The enzyme was a monomer with a molecular mass about 41-52 kDa. The enzyme was stable against heating at 35 degrees C for 30 min at pH values over 6-10. Maximum activity was observed at pH 8.0 and around 50 degrees C. The Km values for D-glycerate and ATP were 0.13 mM and 0.13 mM, respectively. The enzyme showed high specificity for D-glycerate, and was activated by potassium and ammonium ions. The reaction product of the enzyme was identified as 2-phosphoglycerate.

Bacteria↗
PubMed1992

Role of perivenous areolar tissue in the viability of venous flaps: an experimental study on the inferior epigastric venous flap of the rat.

This study was performed to investigate how the perivenous areolar tissue affects survival of the rat inferior epigastric venous flap model designed by Yuen and Leung (1991). Five groups of flaps were studied; group A--flap based on an inferior epigastric vein and areolar tissue; group B--flap with a skeletonised vein; group C--control, nonvascularised flap; group D--flap based on perivascular areolar tissue alone; group E--flap with a skeletonised artery and vein. Each group included 40 flaps; 20 of them had a silicone sheet placed under the flap, the other 20 did not. All flaps of group E survived. The success rate of group A with and without a silicone sheet was 60% and 90% respectively. All flaps of the other groups (B, C, D) necrosed. Histological examination of the pedicle showed that many minute vascular channels (single-cell-layered capillaries) were present apart from the inferior epigastric vein. This result confirms the importance of the perivenous areolar tissue in perfusion of the skin island, at least, in the inferior epigastric venous flap in the rat.

Animals↗
PubMed1992

The directions of static skin tensions in the face: their roles in facial incisions.

The circular excisions of facial skin lesions were performed in 202 sites on 126 patients. The shapes of the resultant defects were observed to identify the directions of skin tensions in a static state. The round shapes remained in the forehead, temple, and nose. In the other areas of the face, the wounds were stretched in certain directions and became elliptical. The orientations of the facial static tensions were identical to the wrinkle lines in many facial areas. It is suggested that the wrinkle lines show the optimal directions of selective incisions in most facial areas except for the medial canthus and upper and lower lips.

Adolescent↗
PubMed1992

The viability of revascularized calvarial bone graft in a pig model.

This study compared the vascularity and resorption of calvarial bone flaps based on an undisturbed pedicle and on a previously (4 weeks) detached pedicle of the superficial fascia (galea) and periosteum and free calvarial bone grafts. Nine adult pigs were used, in three of which a silicone rubber compound was injected intravascularly immediately after the transfer confirmed the vascularity of both pedicled bone flaps. In six pigs, volume changes were assessed intraoperatively by a water displacement method and also 12 weeks postoperatively. Both pedicled bone flaps preserved their original volume, whereas free skull grafts showed approximately 50% of volume loss (p less than 0.001). Decalcified hematoxylin and eosin sections of the specimens obtained 12 weeks postoperatively showed a normal calvarial appearance in both pedicled bone flaps and extensive fibrous tissue infiltration into free grafts. It is suggested that a previous detachment of galea and periosteum does not interfere with the use of vascularized calvarial bone graft, which may provide a more predictable result than a free bone graft.

Animals↗
PubMed1992

Comparison of inorganic bovine bone mineral particles with porous hydroxyapatite granules and cranial bone dust in the reconstruction of full-thickness skull defect.

Twenty adult rabbits were used to evaluate the biocompatibility and osteoconductivity of Bio-Oss, an inorganic bovine bone mineral, in the reconstruction of full-thickness skull defects. Skull defects were treated with either autogenous bone dust, porous hydroxyapatite granules, Bio-Oss particles, or were left untreated as controls. Histological examination of decalcified sections showed incorporation of Bio-Oss into the host tissue without a significant inflammatory reaction. Measurement of the profile area occupied by the bone revealed that Bio-Oss, hydroxyapatite, and the control had the same amount of bone ingrowth, whereas autogenous bone dust produced a greater amount of bone (p < 0.01). We conclude that Bio-Oss, like porous hydroxyapatite, has sufficient osteoconductive properties and can also be used as a bone substitute material.

Animals↗
PubMed1992

Inhibition by fibrin coagulation of lung cancer cell destruction by human interleukin-2-activated killer cells.

We examined the effect of fibrin coagulation on tumor cytotoxicity mediated by human lymphokine (IL-2)-activated killer (LAK) cells. LAK cells were induced from peripheral blood mononuclear cells (MNC) by culture with recombinant IL-2 for 4 or 5 days, and LAK cell-mediated cytotoxicity against tumor cells was assessed by 51Cr release assay in the presence or absence of plasma from normal subjects and lung cancer patients. Plasma did not affect the phase of induction of LAK activity by IL-2, but dose-dependently inhibited the effector phase of LAK cell-mediated cytotoxicity against Daudi cells. Similar inhibition of LAK cell-mediated cytotoxicity was observed on pretreatment of Daudi cells and human lung cancer cell lines with human fibrinogen plus thrombin. A parallel relationship was found between the amount of fibrinogen in plasma of lung cancer patients and inhibition of LAK cytotoxicity. This inhibition was reduced by addition of anticoagulants (heparin or argatroban). These findings suggest that fibrin coagulation on tumor cells protects them from LAK cell-mediated tumor cytotoxicity in malignant lesions and that a combination of an anticoagulant drug and IL-2/LAK therapy may be effective for treatment of lung cancer patients.

Aged↗
PubMed1992

Changes in the level of plasma cortisol, progesterone and total testosterone in developing hairless dogs.

Changes in the levels of plasma cortisol, progesterone and total testosterone were examined in developing hairless and haired dogs. Cortisol levels in the hairless dogs seemed to be higher than those in haired dogs within the age of 4-5 weeks. No apparent changes were seen in the level of plasma progesterone between the groups of hairless females and haired females. Total testosterone levels in hairless males showed to be significantly lower than those in haired males at the age of 13-21 weeks.

Animals↗
PubMed1992

Lymphocyte blastogenesis in hairless dogs following stimulation by various mitogens.

Lymphocyte blastogenesis in hairless descendants of Mexican hairless dogs was examined using the following mitogens: phytohemagglutinin (PHA-M), Concanavalin A (Con A), lipopolysaccharide (LPS) and pokeweed mitogen (PWM). Blastogenetic responses to these mitogens were measured by glucose consumption test (GCT) and compared with those of haired beagle dogs. The response to PHA-M was significantly less in the hairless dogs than in the beagles. No significant differences in the responses to Con A, PWM and LPS were recognized. These results indicated T-cell dysfunction in the hairless dogs, coinciding with our previous work showing reduction of the delayed-type hypersensitivity reaction and early degeneration of the thymus.

Animals↗
PubMed1992

The vascular anatomy of the galeal flap in the interparietal and midline regions.

The potential extension of the galeal flap in the interparietal area was studied on 17 fresh human cadaver heads by intravascular dye injection technique. It was demonstrated that an ipsilateral superficial temporal artery that supplies the galeal flap does not cross the midline or anastomose with the contralateral superficial temporal artery but ensures the survival of a flap extended up to 1 cm proximal to the sagittal suture line. The width of the temporoparietal flap can be extended up to 15 cm, depending on the vascular pattern of the superficial temporal artery. When required, the lateral extension may provide the required soft-tissue bulk despite the reduced flap length.

Aged↗
PubMed1991

Nasal bone haemangiomas: rare entities treatable by craniofacial approach.

Three cases of haemangioma of the nasal bone are illustrative of a rare clinical entity. These were treated by current craniofacial surgical techniques. The advantages of this approach are obvious minimising of the facial deformity, obtaining autologous cranial bone graft and rigid fixation to enhance stability and minimise resorption.

Adult↗
PubMed1991

"Side table assembly"--an adjuvant to craniofacial reconstruction.

Plates and screws are used extensively in craniofacial surgery; they have increased the speed of this surgery, but this can be made even more efficient. Utilising an adjacent instrument table, the rearrangement and reassembly of bone segments resulting from osteotomy or fracture can be performed by a second surgical team using plates and screws. At the conclusion of the operation, the reassembled bony reconstruction can rapidly be placed in position with a minimum of additional screws. This technique has been found to be technically easier and to afford a considerable saving of operating time.

Bone Plates↗
PubMed1991

Microscopic observations of skin and lymphoid organs in the hairless dog derived from the Mexican hairless.

The skin and lymphoid organs of Mexican hairless dogs and their hairless offspring were examined histologically. The hairless dogs lacked most hairs except for sparse hairs on the head, tail and feet. The skin of newborn pups consisted of a thick epidermis with epidermal ingrowths forming the rudiments of hair follicles. In older dogs more than 2 months of age, however, the epidermis was thin and the ingrowths were few. Neither hair follicles nor skin glands were present. The hairy skin of the head and tail had hair follicles with sebaceous glands. Regarding the lymphoid organs, the newborn pups possessed a thymus like haired pups. But in the older dogs more than 2 months of age, the thymus was atrophied and the lymphocyte population was too sparse to demarcate the cortex and the medulla. Lymphocyte accumulation in older dogs was also poor in the spleen and mesenteric lymph nodes. The present findings indicate that the hairlessness of the Mexican hairless dogs and their descendants is accompanied by early atrophy of the thymus after birth, and is followed by poor accumulation of lymphocytes in the thymus-dependent area of the spleen and the mesenteric lymph nodes. The defect of the thymus in the hairless dog seems to be different from that in athymic nude mice and rats. Further studies are needed to elucidate the immunological response and function in hairless dogs.

Animals↗
PubMed1991

Local adoptive immunotherapy using lymphokine-activated killer cells and interleukin-2 against malignant pleural mesothelioma: report of two cases.

Malignant pleural mesothelioma is refractory to conventional therapy. We tried local adoptive immunotherapy using lymphokine-activated killer (LAK) cells and interleukin-2 (IL-2) to control malignant pleural effusion due to mesothelioma in two patients: Case 1 was that of a 69-year-old man, and Case 2 that of a 49-year-old woman with complicating chronic idiopathic thrombocytopenic purpura. A systemic survey revealed no sign of metastasis in either case. Intrapleural instillations of 6.7 x 10(9) autologous LAK cells in Case 1, or 11.3 x 10(9) allogeneic LAK cells in Case 2, with daily injections of IL-2 resulted in reductions of the pleural effusions in each case and in a decline in the level of hyaluronic acid in the effusion, in Case 1. The instillations of autologous and allogeneic LAK cells were well tolerated. The results suggest that local adoptive immunotherapy could be useful in the treatment of malignant effusion due to mesothelioma.

Aged↗
PubMed1990

Epidermoid cyst and cholesterol granuloma of the orbit.

Epidermoid cyst and cholesterol granuloma have been confused, but these are different lesions. A case of recurrent orbital epidermoid cyst and another case of orbital cholesterol granuloma are presented in order to describe their distinct pathological, clinical and imaging characteristics and their surgical management. Advanced investigation using our custom-designed three-dimensional imaging allowed a better appreciation of the exact location, and optimal planning of the surgical treatment. The same surgical approach was used for both lesions: total resection via a coronal incision and immediate reconstruction of residual defects using skull bone grafts.

Adult↗