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Biomedical subjects

I Ono

Publications and source records attributed to I Ono.

At least 37 records · Page 2Linked to original sources
PubMed1999

Effects of a collagen matrix containing basic fibroblast growth factor on wound contraction.

We evaluated the effectiveness of basic fibroblast growth factor (bFGF) in inhibiting wound contraction, both alone and in combination with collagen matrix, using a simulated in vivo delayed healing type model. We also studied the mechanisms involved in this inhibition in in vitro experiments using fibroblast populated collagen gels. As a result, we were able to demonstrate that both collagen matrix and bFGF significantly inhibited wound contraction; especially, bFGF acted in a dose-dependent fashion. Interestingly, their combination was much more effective than either collagen matrix or bFGF alone, a finding that was supported by the histopathological data. Wounds treated with collagen matrix, but not control wounds, showed horizontal rearrangement of collagen fibers in dermis as well as evidence of fibroblast proliferation, which was not observed in scar regions surrounded by normal dermis. Using fibroblast-populated collagen gel contraction as an in vitro model, we found that bFGF significantly inhibited contraction. Taking all these results together, it was concluded that collagen matrix is useful not only as a carrier of cytokines such as bFGF, but also for the quick closure of chronic wounds, thereby preventing contracture, which remains one of the most challenging problems in treating this type of wound. Application of bFGF-treated collagen matrix to chronic wounds such as decubitus, and diabetic and leg ulcers may prove to be highly beneficial in clinical practice.

Animals↗
PubMed1999

Porous hydroxyapatite ceramics and their ability to be fixed by commercially available screws.

We developed porous hydroxyapatite ceramics (HAP) which are screw fixable and evaluated the fixing abilities of commercially available screws using pull-out tests with the HAP implants. The fixing abilities were higher in the following order: Leibinger micro PLUS titanium screw > Osteomed M3 titanium screw > Leibinger standard mini screw > Martin-drill free screw. In preliminary examinations, the fixing ability of each of the screws differed according to the hole diameter and depth of insertion but if inserted under optimum conditions, all were deemed to have adequate fixing ability for clinical applications. Therefore, screw systems are superior for fixing HAP implants to surrounding bone than the use of thread or wire. Specifically, Leibinger's micro PLUS titanium screws system seems to be a good option currently. The fact that effective fixation was achieved should result in a further increase in the clinical use of synthetic porous HAP implants whose porosity and pore size are completely controlled for those purposes.

Analysis of Variance↗
PubMed1999

One-stage reconstruction of microtia in microform.

We treated five patients with auricular deformities (microtia in microform and group IIB or III constricted ears) using the following procedure: nearly all of the contralateral conchal cartilage was resected, grafted, and sutured to supplement a cartilaginous deficit and to keep the supporting frame of conchal cartilage expanded by the double banner flap method. After this, a soft tissue deficit was reconstructed by our newly developed method of covering the defect with a triangular flap superior to the auricle by making a skin incision and a rhomboid flap anterior to the auricle. So far, we have obtained satisfactory results using this one-stage procedure.

Child↗
PubMed1999

Treatment of large complex cranial bone defects by using hydroxyapatite ceramic implants.

Hydroxyapatite ceramic implants were used in the reconstruction of very large and complex-form cranial bone defects in nine patients. The bone defects were the result of craniectomy after infections and other complications such as severe brain edema, after neurosurgery, and as a result of trauma, subdural hemorrhage, and surgery for brain tumor. The size, shape, and curvature of the hydroxyapatite ceramic implants were determined based on high-precision, full-scale models fabricated through a laser lithographic molding method by using computed tomographic data. The use of this method allowed the fabrication of hydroxyapatite ceramic implants of shapes that accurately matched the area of bone defect, allowing for a minimum of adjustment during the operation even with a complex-form implantation. Not only were good cranial contour reconstructed and aesthetically satisfactory results obtained in the cases treated by incorporating this series of techniques, but neurologic conditions present in some cases were also improved to some extent. The postoperative course has been steady for all nine patients, with no blood transfusions required during or after the operations and no implants requiring removal because of infection or other postoperative complications. The average length of postoperative hospitalization for the nine cases was 11.7 days, remarkably short considering the clinical conditions.

Aged↗
PubMed1999

Infantile pulmonary alveolar proteinosis with interstitial pneumonia: bilateral simultaneous lung lavage utilizing extracorporeal membrane oxygenation and steroid therapy.

An infant with refractory pulmonary alveolar proteinosis (PAP) associated with severe interstitial pneumonia is described. Although she was treated by bilateral simultaneous lung lavage utilizing extracorporeal membrane oxygenation and steroid therapy, she died of progressive respiratory failure 28 days after admission. Histologic examination of lung autopsy specimen showed only partial alveolar spaces to be filled with a dense PAS positive granular eosinophilic material and showed severe interstitial pneumonia with marked fibrosis of alveolar walls and interstitium. The lung lavage seemed to be effective for PAP because the effluent fluid sufficiently became clear and the PAS positive material was detected only in partial alveoli. The full venoarterial cardiopulmonary bypass with extracorporeal membrane oxygenation seemed to be very useful to support bilateral lung lavage for small infants. The refractory symptoms and failure of treatment were resulted from the association of severe interstitial pneumonia. In neonates or infants with PAP and severe interstitial pneumonia with poor response for steroid therapy, the lung transplantation should be considered.

Bronchoalveolar Lavage↗
PubMed1999

[Roles of cytokines in wound healing processes].

In recent years, a number of studies have revealed the importance of cytokines and growth factors in the wound healing process. Cytokines, such as epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), transforming growth factor (TGF) alpha 1 and interleukin (IL)-6, have been shown to exhibit the particular ability to stimulate keratinocyte proliferation. In addition, bFGF and TGF beta 1 not only facilitate the migration of monocytes, neutrophils, macrophages, and fibroblasts, but also play a role in the generation of granulation tissue. Cytokine modulation of the repair process in both transitory and chronic wounds remains a very important subject for investigation. In this study, the clinical application of cytokines or cytokine-promoting drugs which were combined with or without collagen matrix is discussed as well as perspectives on wound care in the future.

Animals↗
PubMed1999

Establishment and characterization of human choriocarcinoma cell line derived from a metastatic focus of a testicular mixed germ cell tumor.

A human testicular choriocarcinoma cell line HKRT-II was established by the single-cell cloning method from a mixed cell culture system derived from a retroperitoneal metastatic germ cell tumor composed of a yolk-sac tumor, a choriocarcinoma, and an immature teratoma. Its primary tumor rose from the testis and was comprised of a seminoma, a yolk-sac tumor, a choriocarcinoma and an immature teratoma. The HKRT-II cells were spindle or polygonal in shape and contained multi-nucleated giant cells showing neoplasticity and pleomorphism. The cells proliferated in a stable manner, and the population doubling time was 42 hours. The chromosome numbers showed a wide distribution of aneuploidy, while the mode was in the hypertetraploid range. Double minute chromosomes and homogeneously staining regions were recognized in about 5% to 10% of the metaphase plates, respectively. Heterotransplantation was not difficult. Subcutaneous transplantation of 1 x 10(7) cells into nude mice formed a tumor composed of only a choriocarcinoma. The most noteworthy characteristics of the cell line were that it produced human chorionic gonadotropin (hCG) in an in vitro culture system and in in vivo grafted cells, and that the N-myc gene was amplified about 10 times.

Adult↗
PubMed1998

Determination of ascorbic acid in food by column liquid chromatography with electrochemical detection using eluent for pre-run sample stabilization.

Determination of ascorbic acid (AA) in food was performed by column liquid chromatography with electrochemical detection using an eluent (100 mM KH2PO4 (pH 3) with 1 mM ethylenediaminetetraacetic acid disodium dihydrate) for pre-run sample stabilization. The applied potential was set at 400 mV vs. an Ag/AgCl reference electrode. The proposed method was simple, rapid (analysis time: ca. 8 min), sensitive (detection limit: ca. 0.5 ng per injection (20 microliters) at a signal-to-noise ratio of 3), highly selective and reproducible [relative standard deviation: ca. 1.8% (n = 5)]. The calibration graph for AA was linear in the range 0.1-16 ng per injection (20 microliters). Recovery of AA was over 90% by the standard addition method.

Ascorbic Acid↗
PubMed1998

Determinations of strength of synthetic hydroxyapatite ceramic implants.

To study the physical strengths of various types of synthetic high porosity hydroxyapatite plates, we constructed samples of a fixed shape, 8 X 25 mm in size, with varying degrees of thickness (3 to 10 mm) and porosity (40, 50, and 60 percent), as well as samples with varying degrees of curvature and samples constructed with computer-aided design-computer-aided manufacturing (CAD-CAM) technology based on a real-size model made with laser lithography from computed tomography data. The strength of the samples was studied with the three-point bending test and crush tests. Studies showed that strength decreases with increasing porosity and increases with increasing thickness. In addition, results of testing plates of varying shapes and degrees of curvature revealed that the effects of these variations were small and that when the width and thickness were held constant, changing the curvature of the entire unit (from a height of 20 to 30 mm) or altering both sides had no remarkable effect on strength. On the other hand, strength testing of plates of various shapes and thicknesses constructed from clinical computed tomography data revealed that minimum optimization of the parameters was achieved when plates had a porosity of about 40 percent and a thickness of about 8 mm.

Biomechanical Phenomena↗
PubMed1998

Efficacy of the ruby laser in the treatment of Ota's nevus previously treated using other therapeutic modalities.

Ruby laser treatment, especially with a Q-switched laser, is remarkably effective for Ota's nevus, although a wide variety of other therapeutic modalities have had limited success. Consequently, laser treatment is now considered the treatment of choice. However, for Ota's nevus previously treated with dry ice cryotherapy (carbon dioxide snow), dermabrasion, free skin grafting, or other methods, therapy is still a challenge, even with the ruby laser. In this study, 14 patients with Ota's nevus previously treated using other modalities were treated using a Q-switched ruby laser. Eight patients previously underwent dry ice cryotherapy, three patients underwent free skin grafting, two patients underwent dermabrasion, and one patient received a cosmetic tattoo. The study group was composed of five male and nine female patients. The ages of the patients at the start of treatment ranged from 5 to 62 years. We concluded, based on the findings of this study, that Q-switched ruby laser therapy can provide favorable results even with lesions previously treated by other therapeutic modalities, provided that the treatment sessions are repeated more frequently and over a longer period of time than those used for untreated lesions and that they are combined with plastic surgical techniques such as scar resection or local flaps.

Adolescent↗
PubMed1998

[Intra-arterial infusion chemotherapy for advanced endometrial cancer before surgical treatment].

Nine cases of advanced uterine body cancer (stage III: 8, stage IVa: 1) were treated by intra-arterial infusion chemotherapy before curative operation. This treatment produced primary tumors smaller than half sizes in eight cases. Necrotic changes were found in over two-thirds of the lesions in six cases. This chemotherapy enabled us to operate curatively in seven cases. After the operations, we performed various types of treatment including intra-arterial infusion chemotherapy. No evidences of disease have been found in four cases, but there is no significant difference between the groups receiving and not receiving the intra-arterial infusion chemotherapy (n = 16) in terms of survival rate of stage III. Further study of the prognosis is necessary.

Adenocarcinoma↗
PubMed1997

Determination of N-(trans-4-isopropylcyclohexanecarbonyl)-D-phenylalanine and its metabolites in human plasma and urine by column-switching high-performance liquid chromatography with ultraviolet detection.

A simple, rapid and sensitive two column-switching high-performance liquid chromatographic (HPLC) method with ultraviolet detection at 210 nm has been developed for the determination of N-(trans-4-isopropylcyclohexanecarbonyl)-D-phenylalanine (AY4166, I) and its seven metabolites in human plasma and urine. Measurements of I and its metabolites were carried out by two column-switching HPLC, because metabolites were classified into two groups according to their retention times. After purification of plasma samples using solid-phase extraction and direct dilution of urinary samples, I and each metabolite were injected into HPLC. The calibration graphs for plasma and urinary samples were linear in the ranges 0.1 to 10 microg ml(-1) and 0.5 to 50 microg ml(-1), respectively. Recoveries of I and its seven metabolites were over 88% by the standard addition method and the relative standard deviations of I and its metabolites were 1-6%.

Chromatography, High Pressure Liquid↗
PubMed1997

Role of transforming growth factor-beta 1 in fibroblasts derived from normal and hypertrophic scarred skin.

In order to elucidate the effect of transforming growth factor beta 1 (TGF-beta 1) on normal dermal fibroblasts (NDF) and on fibroblasts derived from hypertrophic scar (HSF) tissue, we compared proliferation, the levels of TGF-beta 1 protein and mRNA, the activity of type-I collagen synthesis and collagenase, and the response to recombinant human (rh) TGF-beta 1 in cultures of both types of cells which had been simultaneously collected from the same patients. We also studied the effects of anti-TGF-beta 1 antibody on the proliferation of these two types of fibroblasts in culture. In spite of the fact that the growth rate of HSF was higher than that of NDF, NDF proliferation was more sensitive to the concentration of rhTGF-beta 1. With respect to rates of synthesis, the results obtained in both groups revealed that the production of type-I collagen was higher and collagenase activity was lower in culture supernatants of HSF. However, the addition of rhTGF-beta 1 resulted in a decrease in the collagenase/collagen ratio in NDF, but failed to induce any change in this ratio in HSF. In addition, the production of TGF-beta 1 and the expression of TGF-beta 1 mRNA in HSF were greater than in NDF. Furthermore, anti-TGF-beta 1 antibody reduced the rate of growth of HSF. These results suggest that HSF are able to produce TGF-beta 1, resulting in enhanced proliferation of these cells as well as in a rapid synthesis of type-I collagen through an autocrine mechanism which may lead to hypertrophic scarring.

Adult↗
PubMed1997

Effects of prostaglandin E1 on cultured dermal fibroblasts from normal and hypertrophic scarred skin.

To investigate the role of prostaglandin (PG) E1 in preventing scar formation as well as that of the related cytokines, we culture fibroblasts from hypertrophic scar tissue (SDF) and normal dermis (NDF) collected from patients with scar contracture. We have compared the type I collagen synthesis, type I collagenase activity, and the production of interleukin (IL)-6, IL-8 and transforming growth factor (TGF)-beta(1) in two types of cultured fibroblasts before and after addition of PGE1. Our results demonstrated that levels of type I collagen and TGF-beta(1) production were higher and that type I collagenase activity and IL-8 production were significantly lower in the culture supernatants of SDF. There was no significance difference in IL-6 production between SDF and NDF culture supernatants. On the other hand, PGE1 significantly increased type I collagenase activity and IL-8 production in the SDF culture supernatants and it increased IL-6 and TGF-beta(1) production in both types of fibroblasts. However, there was no effect on synthesis of type I collagen in either group. To further investigate the role of TGF-beta(1) in NDF and SDF, exogenous recombinant human (rh) TGF-beta(1) was added. In NDF group, rhTGF-beta(1) induced a decrease in the type I collagenase/type I collagen ratio, while rhTGF-beta(1) had no effect on the same ratio in the SDF group. These results suggest that PGE1 may have a role in the prevention of hypertrophic scar by increasing the activity of type I collagenase.

Adolescent↗
PubMed1997

Primary maxillary reconstruction after radical maxillectomy using a combined free flap and secondary dynamic suspension.

We report a case of maxillary reconstruction aimed at optimizing facial contour, oral function, and facial animation after radical maxillectomy. In the first stage, using combined latissimus dorsi serratus anterior flaps attached with ribs, we performed a three-dimensional restoration for midface defects. In the second stage, we performed dynamic reconstruction of the nasolabial fold and upper lip using a temporal muscle transposition. As a result, the upper lip was able to be elevated as much as 10 mm when the patient clenched his teeth, and the outcome was judged to be both aesthetically and functionally satisfactory.

Bone Transplantation↗
PubMed1997

Reconstruction of defects of the entire vermilion with a buccal musculomucosal flap following resection of malignant tumors of the lower lip.

We reconstructed a defect of nearly the entire lower vermilion using a buccal musculomucosal flap following resection of a malignant tumor of the lower lip and obtained satisfactory results. The buccal musculomucosal flap was semi-spindle shaped and pedicled at the angle of the mouth. A flap measuring as much as 1.5 cm in width and 5 cm in length could be raised while ensuring that fibers of the buccinator muscle extended over its entire length. Using this technique, it was possible to reconstruct a wide defect following tumor resection and removal of almost the entire lower vermilion by means of only a transposition of a unilateral buccal musculomucosal flap after about one-quarter of the lower lip had been excised and sutured primarily. Reconstruction with this technique is a two-stage operation, and a secondary minor touch-up operation is performed on the angle of the mouth at the same time as repair of the dog-ear of the pedicle. Advantages of this technique are that food can be taken orally soon after the operation, hemodynamics in the flap are maintained stably because the flap contains fibers of the buccinator muscle, and the vermilion is given a natural eminence. In addition, postoperative drooling is minimized, and sensation returns to the vermilion within the early postoperative period. Based on these advantages, we think our technique should be the first choice for carrying out reconstruction of defects that are located mainly in the lower lip vermilion because this is a safe and reliable method with which we performed 12 cases of vermilion reconstruction without flap necrosis and with satisfactory aesthetic and functional results.

Aged↗