Biomedical subjects

K Bessho

Publications and source records attributed to K Bessho.

At least 37 records · Page 2Linked to original sources

PubMed2000

Bone induction by Escherichia coli -derived recombinant human bone morphogenetic protein-2 compared with Chinese hamster ovary cell-derived recombinant human bone morphogenetic protein-2.

Most recombinant human bone morphogenetic protein (rhBMP) is currently obtained from Chinese hamster ovary (CHO) cells. If rhBMP with more activity could be derived from Escherichia coli (E. coli), a large quantity of rhBMP could be produced at low cost. The bone-inducing ability of an E. coli -derived rhBMP-2 (ErhBMP-2) variant with an N-terminal sequence was examined and compared with CHO cell-derived rhBMP-2 (CrhBMP-2). Two, 10, or 50 microgram of ErhBMP-2 or CrhBMP-2 was mixed with 3mg of atelopeptide type I collagen as the carrier, and specimens were implanted into the calf muscle pouches of Wistar rats (n= 5 in each group). Three weeks later, new bone had formed in all the ErhBMP-2-implanted and CrhBMP-2-implanted muscles. Radiographic and histological examinations showed that the bone induced by ErhBMP-2 had a large hollow bone matrix with more fatty marrow than the bone induced by CrhBMP-2. Quantitative analysis indicated that the activity of ErhBMP-2 was similar to that of CrhBMP-2, so ErhBMP-2 may be useful for inducing bone formation.

Alkaline Phosphatase↗

PubMed2000

The effect of blood supply in muscle and an elevated muscle flap on endogenous tissue-engineered bone by rhBMP-2 in the rat.

Metabolism and remodeling of bony tissue are maintained and controlled by blood supply. In this study, bony tissue osteoinduced heterotopically by recombinant human bone morphogenetic protein-2 (rhBMP-2) in rat muscles with different amounts of blood supply was investigated. The implant beds were in the latissimus dorsi muscle (LDM) and in the space wrapped with an elevated latissimus dorsi muscle flap (LDMF). The blood flow was preestimated at two muscle sites using a laser Doppler blood flowmeter. The flow value of the LDM was 2.23 +/- 0.17 ml/min/100 g (mean +/- standard deviation). The flow values of the LDMF were 1.71 +/- 0.22 ml/min/100 g 30 minutes after elevating the LDMF, 1.75 +/- 0.20 ml/min/100 g after 1 week, 1.83 +/- 0.19 ml/min/100 g after 2 weeks, and 1.99 +/- 0.18 ml/min/100 g after 3 weeks. Bony tissues induced heterotopically by rhBMP-2 were examined radiographically and histologically. On radiographs, radiopaque shadows in the LDM were almost as large as those in the LDMF. The radiopacity in the LDM was a little higher than that of the LDMF. The microscopic findings showed increased trabeculae and more hematopoietic marrow in the LDM than lamellalike bone in the LDMF. Mean bony area in the implant was 1.05 +/- 0.26 mm2 in the LDM, and was 0.70 +/- 0.11 mm2 in the LDMF. Bony proportions in the overall implant area were 18.3 +/- 3.46% in the LDF and 12.1 +/- 2.18% in the LDMF. The current study indicates that blood supply is an important factor for promoting heterotopic osteoinduction by rhBMP-2 to produce massive bony tissue as an endogenous method of tissue engineering.

Animals↗

PubMed2000

Osteogenesis by recombinant human bone morphogenetic protein-2 at skeletal sites.

Osteogenesis was evaluated in the mandibular bone by combinations of various dosages of recombinant human bone morphogenetic protein-2, atelopeptide Type I collagen, and porous hydroxyapatite (four groups: Group I, 2 micrograms recombinant human bone morphogenetic protein-2, atelopeptide Type I collagen, and porous hydroxyapatite; Group II, 10 micrograms recombinant human bone morphogenetic protein-2, atelopeptide Type I collagen, and porous hydroxyapatite; Group III, 50 micrograms recombinant human bone morphogenetic protein-2, atelopeptide Type I collagen, and porous hydroxyapatite; Control Group, only atelopeptide Type I collagen and porous hydroxyapatite). The prepared materials were implanted in the mandibular bone hole (7 mm in diameter, 2 mm deep). Three weeks later, the alkaline phosphatase activity in the implanted region was determined, and the histologic features of the excised tissue were examined. There were significant differences in histologic and biochemical findings among the four groups. In the recombinant human bone morphogenetic protein-2 implanted groups, osteogenesis increased with the dosage of recombinant human bone morphogenetic protein-2, as assessed by alkaline phosphatase activity and histologic findings. The results suggest that atelopeptide Type I collagen is an effective carrier for recombinant human bone morphogenetic protein-2 and that porous hydroxyapatite would be advantageous for clinical application as a material to maintain its original form after implantation.

Alkaline Phosphatase↗

PubMed2000

Osteoinduction by recombinant human bone morphogenetic protein-2 at intramuscular, intermuscular, subcutaneous and intrafatty sites.

To compare the osteoinductive activity of recombinant human bone morphogenetic protein-2 (rhBMP-2) at various sites in rats, 5 microg of rhBMP-2 were implanted into various sites, using atelopeptide type-I collagen (CL) as a carrier (BMP groups). CL implantation was used as a control. Forty Wistar rats were divided into intramuscular, intermuscular, subcutaneous and intrafatty site groups (IrM, IeM, SC and IF, respectively). Bone formation was evaluated radiographically, histologically and biochemically 21 days after implantation. In the BMP groups, the alkaline phosphatase activity and calcium content at all sites were higher than those in the control groups. Among the BMP groups, the new bone formation was highest in the IrM and lowest in the IF radiographically, histologically and biochemically. Five microg of rhBMP-2, a relatively low dose, induced adequate new bone formation in all sites. The variations of osteoinductive activity of rhBMP-2 in various sites may be due to differences in the blood supply.

Adipose Tissue↗

PubMed1999

Expression of bone morphogenetic protein-2 via adenoviral vector in C2C12 myoblasts induces differentiation into the osteoblast lineage.

To examine the effectiveness of a gene transfer of bone morphogenetic protein (BMP)-2 into C2C12 myoblasts, we constructed a human BMP-2-expressing replication-deficient adenoviral vector, AxCAOBMP-2. C2C12 cells were infected in vitro with either this viral vector or an Escherichia coli LacZ gene-expressing control adenovirus vector. An efficient gene transfer to the C2C12 cells was confirmed with the LacZ gene-expressing vector by X-gal staining. Abundant BMP-2 expression in C2C12 cells infected with this viral vector was confirmed by immunofluorescence and Western blot analysis. C2C12 cells transferred with the BMP-2 gene by this vector produced alkaline phosphatase in the cells and also produced and secreted osteocalcin in the culture medium, demonstrating that a gene transfer of BMP-2 into C2C12 cells in vitro could convert these cells from myoblast to osteoblast lineage.

Adenoviridae↗

PubMed1999

Bone morphogenetic protein-2 in temporomandibular joints with internal derangement.

OBJECTIVE: The purpose of this study was to analyze the expression of bone morphogenetic protein-2 (BMP-2) in patients with internal derangement of the temporomandibular joint. STUDY DESIGN: Twenty-one human temporomandibular joint samples (5 extirpated disks and 16 biopsy specimens of synovitis area from patients with internal derangement of the TMJ) and 2 control temporomandibular joint specimens (2 normal disks obtained by autopsy) were analyzed with specific antibodies through use of an immunohistochemical technique. RESULTS: BMP-2 was predominantly localized in chondrocytes around the damaged areas of the articular disks. BMP-2 expression was also found in synovial cells and endothelial cells of blood vessels. Control specimens demonstrated BMP-2 staining in synovial lining cells and endothelial cells of blood vessels. However, the chondrocytes in the normal cartilage layers of the control specimens showed no staining. CONCLUSIONS: These findings suggest that BMP-2 may be involved in the pathogenesis of osteoarthritic changes or the repair process of temporomandibular joint internal derangement.

Adult↗

PubMed1999

Comparative study of intramuscular and intraskeletal osteogenesis by recombinant human bone morphogenetic protein-2.

OBJECTIVE: The purpose of this study was to compare the osteoinducing activity of recombinant human bone morphogenetic protein-2 (rhBMP-2) at intramuscular and intraskeletal sites in rats. STUDY DESIGN: Five tg of rhBMP-2 was implanted into the right calf muscle of each of 20 rats and into a hole (4 mm in diameter, 1.5 mm in depth) that was made in the mandibular body of each of 20 other rats, with atelopeptide type I collagen as a carrier. The alkaline phosphatase activity and calcium content were quantitatively analyzed 1, 3, 7, and 21 days after the implantation of rhBMP-2 into either mandibular bone (in the intraskeletal group) or calf muscle (in the intramuscular group). The new bone formation was evaluated histologically 21 days after implantation. RESULTS: On days 1 and 3, the alkaline phosphatase activity and calcium content in the intraskeletal group showed no significant differences from those in the intramuscular group. On the 7th and 21st days after implantation, however, the alkaline phosphatase activity and calcium content in the intraskeletal group were significantly higher than those in the intramuscular group. Histometry of the microscopic views showed that the mean trabecular area was 0.87 mm2 in the intramuscular group and 2.66 mm2 in the intraskeletal group. CONCLUSIONS: These results suggest that the new bone formation stimulated by rhBMP-2 in the intraskeletal group was greater than in the intramuscular group.

Alkaline Phosphatase↗

PubMed1999

An autopsy case of malignant mesothelioma with osseous and cartilaginous differentiation: bone morphogenetic protein-2 in mesothelial cells and its tumor.

An autopsy case of biphasic malignant mesothelioma with osseous and cartilaginous differentiation diffusely involving the peritoneal cavity was confirmed by light microscopic histochemistry, immunohistochemistry, and electron microscopy. A reverse transcription-polymerase chain reaction using specific primers for bone morphogenetic protein-2 (BMP-2) revealed weak positive transcript in normal mesothelial cells and up-regulated expression around bone-forming malignant mesothelioma tissue. However, BMP-2 protein expression was detected only in the marginal zone of bone trabeculae and spindle-shaped mesothelioma cells distributed around bone trabeculae in tumor tissue. The distribution of type IV collagen in tumor tissue was in accordance with the BMP-2 expression. Normal mesothelial cells and tumor cells expressed BMP-2 mRNA, but the BMP-2 protein expression was restricted to the bone-forming area in the malignant mesothelioma.

Abdominal Neoplasms↗

PubMed1999

BMP stimulation of bone response adjacent to titanium implants in vivo.

The objective of this study was to evaluate the effect of bone morphogenetic protein (BMP) on the bond strength of titanium (Ti) implants at the bone-implant interface. Thirty-six Brånemark screw implants (3.75 mm diameter by 15 mm long) were implanted for 3 and 12 weeks. At 3 weeks after implantation, the mean reverse torque value for implants stimulated with BMP delivered using an atelopeptide type-I collagen carrier (74.2 +/- 5.2 N cm) was observed to be statistically greater (P < 0.000016) than the mean reverse torque value for control Ti implants (32.8 +/- 1.1 N cm). Similarly, at 12 weeks after implantation, the mean reverse torque value for implants stimulated with BMP (89.2 +/- 2.7 N cm) was statistically greater (P < 0.0042) than the mean reverse torque value for control Ti implants (75.8 +/- 2.4 N cm). In addition, histomorphometric evaluations indicated more bone contact with the BMP stimulated implant surfaces compared to the controls after 3 weeks implantation. It was concluded from this study that the use of BMP-atelopeptide type-I collagen mixture is an effective means of obtaining greater bond strength at the bone implant interface within a shorter time period than Ti implants without BMP.

Animals↗

PubMed1999

Comparison of recombinant and purified human bone morphogenetic protein.

Clinically, it would be more convenient to use recombinant than purified preparations of bone morphogenetic protein (BMP). Recently, recombinant human BMP (rhBMP) has attracted the attention of many investigators, but it has not been fully characterized. We examined the bone-inducing activity of rhBMP-2 and compared it with that of purified BMP derived from human bone matrix (phBMP). Two, 10, or 50 microg of rhBMP-2 or phBMP was mixed with 3 mg of atelopeptide type I collagen (carrier), and specimens were implanted in the calf muscles of Wistar rats (n=5 in each group). Four weeks later, new bone had formed in all the rhBMP-2- and phBMP-implanted muscles and was visible radiographically and histologically. The quantitative analysis indicated that the activity of rhBMP-2 was less than one tenth that of phBMP. It is necessary to find out why rhBMP-2 has fewer activities than phBMP.

Alkaline Phosphatase↗

PubMed1999

Enhancement by recombinant human bone morphogenetic protein-2 of bone formation by means of porous hydroxyapatite in mandibular bone defects.

Hydroxyapatite is osteoconductive and can maintain an original biocompatible form. It is useful, in the reconstruction of bone defects, to enhance the osteoconduction of hydroxyapatite with an osteogenic protein. The aim of this study was to evaluate the bone formation in surgically created defects of rabbit mandibles by a combination of recombinant human bone morphogenetic protein-2 (rhBMP-2), with porous hydroxyapatite and atelopeptide type I collagen used as the carrier for rhBMP-2. A 10-microg rhBMP-2-implanted group (n = 15) and a control group (n = 15), in which only atelopeptide type I collagen and porous hydroxyapatite were implanted, were histologically examined 3, 7, and 21 days after implantation. The alkaline phosphatase activity was also quantitatively analyzed. No new bone formation was observed in either the tested or the control group after 3 days. At 7 days, immature bone tissue was observed in some pores of the rhBMP-2implanted group, while in the control group, immature mesenchymal cells were observed. At 21 days, trabecular bone lined some pore walls. In the central portion, the bone marrow, including angioid tissue, was observed. New trabecular bone formation was observed on portions of the external surface of the hydroxyapatite disk. On the other hand, the control group showed infiltration of immature mesenchymal cells into some pores. Marginal bone formation was found in the pores close to the surface of the disk which opposed mandibular bone. The control group showed a slow, small increase in alkaline phosphatase activity in this study, while the experimental group showed a marked increase at 21 days. This increase was significantly higher in the tested group than in the control group at both 7 and 21 days. The findings indicate that rhBMP-2 accelerated bone formation by osteoconduction from porous hydroxyapatite. The combination of rhBMP-2, atelopeptide type I collagen, and porous hydroxyapatite is suggested to be advantageous for clinical application in reconstructing mandibular bone defects.

Alkaline Phosphatase↗

PubMed1999

Osteoblast progenitor cell responses to characterized titanium surfaces in the presence of bone morphogenetic protein-atelopeptide type I collagen in vitro.

The goal of this study was to investigate the effect of bone cell response to titanium (Ti) surfaces in the presence of bone morphogenetic protein (BMP)-atelopeptide type I collagen mixture. The atelopeptide type I collagen was used as a potential carrier for the BMP. Sterilized 600-grit Ti samples were used as substrates for the cell culture study. X-ray photoelectron spectroscopy indicated the presence of TiO2 on the Ti surface. The in vitro cell culture study was performed using an osteoblast progenitor cell line derived from mice (2T9). At confluency, the cells cultured on Ti surfaces were divided into three groups: unstimulated culture, culture stimulated by BMP-atelopeptide type I collagen (40 ng/mL), and culture stimulated by atelopeptide type I collagen (40 ng/mL). The unstimulated and atelopeptide type I collagen cultures were controls in this study. After 4 days of incubation, protein production, alkaline phosphatase (ALP) activity, and hexosaminidase activity were observed to be the highest for cells exposed to the BMP-atelopeptide type I collagen mixture. Statistical differences in cellular protein production and ALP activity were observed between the controls and the surfaces exposed to the BMP-atelopeptide type I collagen mixture. Similarly, a statistical difference in hexosaminidase activity was observed between unstimulated Ti surfaces and surfaces exposed to BMP-atelopeptide type I collagen mixture. However, no statistical differences in protein production, ALP activity, and hexosaminidase activity were observed between cells exposed to atelopeptide type I collagen solution and the unstimulated surfaces.

Alkaline Phosphatase↗

PubMed1998

The use of a new bilayer artificial dermis for vestibular extension.

In this study we evaluated the usefulness of a new bilayer artificial dermis (TERUDERMIS; Terumo Corporation, Japan) for vestibular extension. It is composed of a collagen sponge with the silicone layer which is sloughed off as the mucous membrane heals. We have used it for vestibular extension in 50 patients. The material was effective in nearly all patients in promoting haemostasis, relieving pain, inducing granulation, promoting rapid epithelialization, and preventing contracture. There were no side-effects. The greatest problem with such materials in the past has been contracture at the vestibular extension area. However, we found that the degree of contracture was similar to that seen with autogenous mucosa or free skin graft. Our results indicate that the material might be useful for vestibular extension.

Adolescent↗

PubMed1998

Outcome of arthroscopic surgery to the temporomandibular joint correlates with stage of internal derangement: five-year follow-up study.

We studied the 5-year long-term outcome of arthroscopic surgery, and also investigated whether outcome correlates with stage of internal derangement of the temporomandibular joint (TMJ). A consecutive group of 41 patients (56 joints) who had been followed up for between 3 and 5 years were involved in this study. The result was excellent in 22 patients (54%) and fair in 15 (37%). 7/14 were excellent and 5/14 were fair in stage III, 7/12 were excellent and 4/12 were fair in stage IV, and 8/15 were excellent and 6/15 were fair in stage V. Arthroscopic surgery of the TMJ is an effective and minimally invasive technique for various stages of internal derangement.

Activities of Daily Living↗

PubMed1998

Synthesis and evaluation of nitro 5-deazaflavin-pyrrolecarboxamide(s) hybrid molecules as novel DNA targeted bioreductive antitumor agents.

A series of 6-nitro-5-deazaflavins bearing at N(3) or N(10) position the pyrrolecarboxamide(s) group as DNA minor groove binder has been synthesized. These hybrid molecules show similar redox properties to those of 6-nitro-5-deazaflavins with no pyrrolecarboxamide(s) group, suggesting that they generate stable one- and two-electron reduction product(s). Electrolytic reductions of the hybrid molecules were carried out at a controlled potential under anaerobic conditions in the presence of plasmid pBR322 DNA. Significant conversions of the supercoiled circular pBR322 DNA (form I) to the open circular DNA (form II) have been found by treatment with the reductively activated 6-nitro-5-deazaflavin derivatives. Their DNA damaging effects have been found to be enhanced as the number of pyrrolecarboxamide group as the DNA binder increases. Antitumor activities of the hybrid molecules towards KB and L1210 cells were evaluated in vitro. It has been found that the antitumor effects of the compounds on KB cells slightly change and those on L1210 cells decrease as the number of the pyrrolecarboxamide group increases. These results reveal that the combination of 6-nitro-5-deazaflavin molecule with the pyrrolecarboxamide(s) group increase the DNA binding properties of the compounds, giving rise to promoted DNA damaging effects, and also suggest that the combination would affect the capacity of the compounds to act as the substrate for intracellular reductases and/or the cellular uptake of the compounds.

Animals↗

PubMed1998

Osteoinduction capability of recombinant human bone morphogenetic protein-2 in intramuscular and subcutaneous sites: an experimental study.

The osteoinduction capability of recombinant human bone morphogenetic protein-2 (rhBMP-2) in the muscle and in the subcutaneous tissue in Wistar rats (n = 20) was evaluated, using atelopeptide type-I collagen as a carrier. The alkaline phosphatase (ALP) activity and calcium (Ca) content were quantitatively analyzed 1, 3, 7 and 21 days after the implantation of 5 micrograms of rhBMP-2. At 3 days, the ALP activity began to increase gradually. The Ca content showed a slow increase until 7 days and was markedly elevated at 21 days. There was no significant difference observed between the intramuscular and subcutaneous sites until 3 days. However, at 7 days, both the ALP activity and Ca content were significantly higher intramuscularly than subcutaneously. Also, at 21 days they were higher in the muscle than in the subcutaneous tissue. These results suggest that the difference in osteoinduction could be related to the partial pressure of oxygen or the blood supply in the intramuscular and subcutaneous sites, and that immature mesenchymal cells in the muscle could more easily differentiate into osteoblasts, leading to osteoinduction. This study clearly demonstrated that even a small amount (5 micrograms) or rhBMP-2 induces new bone in the subcutaneous tissue, which has a lesser blood flow than the muscle.

Alkaline Phosphatase↗

PubMed1998

Effectiveness of kampo medicine (sai-boku-to) in treatment of patients with glossodynia.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of a Kampo medicine (Sai-boku-to) for treatment of patients with glossodynia. STUDY DESIGN: Sai-boku-to or an antianxiety drug (diazepam) with vitamin B complex was administered orally for 3 months to each of 200 patients with glossodynia. Clinical examination evaluated the following subjective symptoms: pain, burning sensation, and discomfort. Effectiveness was evaluated as follows: "markedly effective," all 3 symptoms disappeared; "effective," pain improved; "ineffective," no improvement in pain. RESULTS: The effective rates were 70% after 1 month, 85% after 2 months, and 92% after 3 months of administration of Sai-boku-to (the Kampo group) and 74% after 1 month, 71% after 2 months, and 69% after 3 months of administration of the antianxiety drug with vitamin B complex (the control group). No significant side effect was noted in the Kampo group, but sleepiness was recorded in 33 cases in the control group. CONCLUSIONS: The results indicate that Sai-boku-to may be a clinically useful medicine for the long-term treatment of patients with glossodynia.

Adult↗

PubMed1998

Prefabricated muscle flap including bone induced by recombinant human bone morphogenetic protein-2: an experimental study of ectopic osteoinduction in a rat latissimus dorsi muscle flap.

For skeletal reconstruction, a vascularised bone graft is both reliable and useful, but some sacrifice usually occurs at the skeletal donor site. In the search for our alternative, we investigated ectopic osteoinduction by bone morphogenetic protein in a rat muscle flap, to prefabricate a muscle flap that included bone. Right latissimus dorsi muscle flaps were prepared in 16 rats. Recombinant human bone morphogenetic protein-2 (rhBMP-2; 2, 10 and 50 micrograms) mixed with atelopeptide type I collagen (3 mg) as the carrier was wrapped with the tip of the latissimus dorsi muscle flap. Three weeks later, ectopic osteoinduction in the latissimus dorsi muscle flap was investigated radiologically, histologically and biochemically. A radiological oval shadow was observed in each animal in each rhBMP-2-implanted group. The volume of the oval shadow area in the muscle flap was dependent upon the dosage of rhBMP-2. It indicated that on ectopic osteoinduction by rhBMP-2 in the muscle flap, induced trabeculae were circularly constructed at the margins of the lump. The radio-opacity of the oval shadows was almost equal in all rhBMP-2-implanted groups, and the shadow areas depended on the dosage of rhBMP-2. The biochemical indices of osteogenesis, ALP activity and Ca content in the lump were dependent upon the dosage of rhBMP-2. This study showed that ectopic osteoinduction occurred in the rat latissimus dorsi muscle flap and depended upon the dose of rhBMP-2. Wrapping rhBMP-2 mixed with atelopeptide type I collagen with the tip of a latissimus dorsi muscle flap could create a prefabricated muscle flap that included bone.

Animals↗