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T Ochi

Publications and source records attributed to T Ochi.

At least 145 records · Page 8Linked to original sources
PubMed1998

Elderly-onset rheumatoid arthritis and its association with HLA-DRB1 alleles in Japanese.

To assess the association between HLA-DRB1 and elderly-onset rheumatoid arthritis (RA) (EORA) in Japanese people, we analysed the HLA-DRB1 antigen frequencies of EORA patients. The age at onset distribution of 852 Japanese RA patients was analysed, and EORA was defined as an age at onset of 60 yr or older. Among the 852 RA patients, 120 (14.1%) were EORA patients. Their HLA-DRB1 antigen frequencies were assessed for significant deviation from those of the control (n = 652) and adult-onset RA (AORA; disease onset between 16 and 59 yr; n = 732) groups. The Japanese EORA patients were positively associated with DRB1*0101, *0405 and *1502, and the relative risks were 2.7, 1.9 and 2.2, respectively. The frequency of DRB1*1502 was also significantly higher among the EORA patients than in the AORA patients. The EORA patients showed different trends from the AORA patients in their frequency of HLA-DRB1 alleles, which suggests that EORA may be a different subset from AORA in light of its immunogenetic background.

Adolescent↗
PubMed1998

Hemodynamic measurement in the femoral head using laser Doppler.

The author used a laser Doppler device to measure hemodynamics in the femoral head. Twenty-eight patients with femoral neck fractures, 16 patients with intertrochanteric fractures, and 14 patients with osteoarthritis were studied. Through a lateral approach, a small hole was drilled into the femoral head using a burr, and a probe was inserted to measure intramedullary flow. The flow measurements were high and sinusoidal in shape (corresponding with the heart rate) in all Garden 1, all Garden 2, and in four of six Garden 3 femoral neck fractures. Flow measurements were low and not sinusoidal in two of six Gardens 3 and all Garden 4 fractures. Hemodynamic values were high in all 16 patients with intertrochanteric fractures and all 14 patients with osteoarthritis. Although the posterior column arteries were cut while the intramedullary hemodynamics were being measured in patients with osteoarthritis of the hips, the measured values still were high. The postero-lateral area of the femoral head was fed compensatorily by the inferior retinacular arteries. The laser Doppler is useful in estimating circulatory compromise.

Aged↗
PubMed1998

Involvement of simultaneous multiple transcription factor expression, including cAMP responsive element binding protein and OCT-1, for synovial cell outgrowth in patients with rheumatoid arthritis.

OBJECTIVE: To elucidate possible roles of several transcription factors in the pathogenesis of rheumatoid arthritis (RA), the transcription factor expression in RA synovial tissue and their contribution to RA synovial cell functions were studied. METHODS: Single cell suspension of dissociated synovial tissue was cultured to induce in vitro tissue outgrowth of RA synovial cells. Transcription factors were immunohistochemically identified in RA synovial tissue obtained by joint surgery and in the in vitro tissue outgrowth, and confirmed by western blotting and gel shift assays. RESULTS: Immunohistochemical examination of RA synovial tissue revealed simultaneous expression of various transcription factors (NF-kappa B, c-Jun (a component of AP-1), cAMP responsive element binding protein (CREB), and OCT-1). The same set of transcription factors was expressed in the in vitro tissue outgrowth of RA patients. The early passage RA synovial cells were treated with interleukin 1 beta (IL1 beta) and confirmed translocation of transcription factors into the nucleus by western blotting, and their DNA binding activity by gel shift assays. CONCLUSION: This study emphasises the importance of the simultaneous expression of several transcription factors for the hyperactivity of RA synovial cells that leads to tissue outgrowth.

Adult↗
PubMed1998

Studies on anti-inflammatory agents. VI. Synthesis and pharmacological properties of 2,3-diarylthiophenes.

A series of novel 5-substituted-2,3-diarylthiophenes has been synthesized and found to be active in the rat adjuvant arthritis (AA) model and/or in the yeast-induced hyperalgesia (Randall-Selitto) assay. Among the compounds synthesized herein, 2-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]-5-(trifluoromethyl)thiop hene (6a) exhibited the most potent activities on AA, collagen-induced arthritis (CIA) and the delayed-type hypersensitivity response to type II collagen. 5-Bromo-2-[4-(methylamino)phenyl]-3-[4-(methylsulfinyl)phenyl]thiophene (38) is also a potent inhibitor of AA, CIA, hyperalgesia and in vitro tumor necrosis factor-alpha production.

Adjuvants, Immunologic↗
PubMed1998

Impaired atrial contraction in patients with atrial flutter and gradual recovery after cardioversion.

The risk of thromboembolism after cardioversion of atrial flutter is controversial. The present study provides evidence for blood stasis in the atria of patients with atrial flutter and for gradual recovery of atrial contraction after cardioversion, which justifies prophylactic treatment at cardioversion, as for atrial fibrillation. We examined atrial thrombi and peak flow velocity in the left atrial appendage as an index of blood stasis in 5 consecutive patients with atrial flutter. Transesophageal echocardiography revealed a thrombus in 1 patient, and peak flow velocity in the left atrial appendage was inversely correlated with left atrial dimension (r = -0.90, p < 0.05). After restoration of sinus rhythm, transmitral flow velocity in late diastole was also examined to evaluate the recovery of atrial contraction. The recovery of transmitral flow velocity the next day and 1 week after cardioversion was correlated with flow velocity in the left atrial appendage before cardioversion (r = 0.89, p < 0.05; r = 0.97, p < 0.01, respectively). These findings suggest that some patients with atrial flutter have impaired atrial contraction and that prolonged impairment after cardioversion is also possible. Atrial enlargement and low flow velocity in the atrial appendage were predictive factors for such patients.

Aged↗
PubMed1998

A case of variant angina pectoris with similar findings on both rest and matched exercise thallium-201 studies.

A patient with variant angina showed similar findings on both the rest and matched exercise 201Thallium (201Tl) myocardial perfusion scintigrams. The 65-year old man was admitted to hospital because of rest angina. His electrocardiogram during the attack disclosed ST segment elevation on inferior leads. However, emergency coronary arteriogram showed no fixed stenosis. Intracoronary injection of acetylcholine induced a spasm on the distal right coronary artery, but not in the left coronary artery. In the rest 201Tl study, septal perfusion was low on the early image, although partial redistribution of this site was observed on the delayed image without the appearance of chest pain or electrocardiographic ischemic change. Similary, in the 201Tl exercise study undergone 2 weeks later, septal redistribution was diagnosed because the early image had decreased septal perfusion. Both the exercise 123I-metaiodobenzylguanidine study and the rest 123I-betamethyl-p-iodophenyl-pentadecanoic acid study showed inferior abnormalities on the early and delayed images. Although a coronary spasm was not induced in the left anterior descending artery with the acetylcholine test, septal redistribution was observed on the delayed image of both the rest and exercise 201Tl studies. The mechanism of the redistribution on the rest 201Tl study was unclear.

Aged↗
PubMed1998

The Metal-Cancellous Cementless Lübeck total hip arthroplasty. Five-to-nine-year results.

We implanted 51 Metal-Cancellous Cementless Lübeck (MCCL) prostheses into 45 patients with dysplastic hips and followed 49 hips (96.1%) for five to nine years. One had needed revision for stem fracture and one for infection; the clinical outcome of the other 47 hips was assessed using the Merle d'Aubigné and Postel hip score. All hips were either excellent (63%) or good (37%). Three patients (6%) had mild thigh pain at six months, but this had settled within two years. Serial radiographs showed stable fixation with bone ingrowth in all hips, with increased density of the cancellous bone in contact with the implant and some trabecular ingrowth. There was early varus shift of the stem in one hip, but this stabilised in three months. Osteolysis of the femoral cortex was seen in one hip at seven years after surgery, and mild bone resorption due to stress shielding in 31 (63%). Acetabular bone grafting with autogenous bone from the femoral head gave successful support to the socket in 13 hips. The MCCL prosthesis gave satisfactory mid-term results in patients with osteoarthritis secondary to hip dysplasia.

Acetabulum↗
PubMed1998

The morphology of the femur in developmental dysplasia of the hip.

We studied the morphometry of 35 femora from 31 female patients with developmental dysplasia of the hip (DDH) and another 15 from 15 age- and sex-matched control patients using CT and three-dimensional computer reconstruction models. According to the classification of Crowe et al 15 of the dysplastic hips were graded as class I (less than 50% subluxation), ten as class I/III (50% to 100% subluxation) and ten as class IV (more than 100% subluxation). The femora with DDH had 10 to 14 degrees more anteversion than the control group independent of the degree of subluxation of the hip. In even the most mildly dysplastic joints, the femur had a smaller and more anteverted canal than the normal control. With increased subluxation, additional abnormalities were observed in the size and position of the femoral head. Femora from dislocated joints had a short, anteverted neck associated with a smaller, narrower, and straighter canal than femora of classes I and II/III or the normal control group. We suggest that when total hip replacement is performed in the patient with DDH, the femoral prosthesis should be chosen on the basis of the severity of the subluxation and the degree of anteversion of each individual femur.

Adult↗
PubMed1998

Genotype phenotype correlation in achondroplasia and hypochondroplasia.

Recent studies of the fibroblast growth factor receptor 3 (FGFR3) gene have established that achondroplasia and hypochondroplasia are allelic disorders of different mutations. To determine whether the genotype could be distinguished on the basis of the phenotype, we analysed height, arm span, and skeletal radiographs from 23 patients with achondroplasia and the G380R mutation of FGFR3 and eight with hypochondroplasia and the N540K mutation. Both conditions share the classical pathological features of micromelic short stature, reduced or unchanged interpedicular distances in the lumbar spine, disproportionately long fibulae, and squared and shortened pelvic ilia. These were significantly more severe in the G380R patients than in the N540K patients. Our findings have shown a firm statistical correlation between the genotype and the phenotype, although there were a few exceptional cases in which there was phenotypic overlap between the two conditions.

Achondroplasia↗
PubMed1998

Impaired expression of noncollagenous bone matrix protein mRNAs during fracture healing in ascorbic acid-deficient rats.

In scorbutic patients, fractures are slow to heal because of impaired collagen synthesis. To investigate the influence of impaired collagen synthesis on the differentiation and proliferation of osteogenic and chondrogenic cells, we examined the expression of genes encoding bone matrix proteins, including osteonectin (ON), osteopontin (OPN), osteocalcin (OC), and matrix Gla protein (MGP), as differentiation markers for osteogenic and chondrogenic cells during fracture healing in Osteogenic Disorder Shionogi (ODS) rats, which have a hereditary defect in the ability to synthesize ascorbic acid (Asc). In ODS rats without Asc supplementation, intramembranous ossification was completely inhibited. Although a few fibroblast-like cells expressing ON mRNA were observed, no OPN mRNA-expressing cells were detected. During endochondral ossification, a small amount of metachromatic staining cartilage appeared at the fracture site, but there was no provisional calcification zone in the cartilage. Chondrocytes expressed ON and MGP mRNAs, but not OPN mRNA. When Asc was given to these rats, callus formation was soon detected around the fracture site, while OPN mRNA was expressed by differentiated osteoblasts and hypertrophic chondrocytes. Our data indicate that impaired collagen synthesis due to Asc deficiency inhibited the increase of ON and MGP mRNA-expressing cells as well as the appearance of OPN mRNA-expressing cells. Since OPN is considered to play an important role in normal and pathological mineralization, lack of OPN mRNA expression accompanying impaired collagen synthesis may have a role in defective mineralization and delayed fracture healing in scurvy.

Animals↗
PubMed1998

Expression of bone matrix proteins mRNA during distraction osteogenesis.

Distraction osteogenesis is a recently advanced principle of bone lengthening in which a bone separated by osteotomy is subjected to slow progressive distraction using an external fixation device. Appropriate mechanical tension-stress is believed not to break the callus but rather to stimulate osteogenesis. To study the molecular features of this process, the expression and localization of the mRNAs encoding osteopontin (OPN), osteocalcin (OC), matrix Gla protein (MGP), osteonectin (ON), and collagen type I and I during distraction osteogenesis were examined by in situ hybridization and Northern blot analysis. The process can be divided into three distinct phases: the lag phase for 7 days between osteotomy and the beginning of distraction, the distraction phase for 21 days, and the consolidation phase for several weeks. The histologic and molecular events taking place during the lag phase were similar to those observed in fracture healing. The osteotomy site was surrounded by external callus consisting of hyaline cartilage. As distraction started at the rate of 0.25 mm/12 h, the cartilaginous callus was elongated, deformed, and eventually separated into proximal and distal segments. The chondrocytes were stretched along the tension vector and became fibroblast-like in shape. Although morphologically these cells were distinguishable from osteogenic cells, they expressed OPN, OC, and alkaline phosphatase mRNAs. As distraction advanced, the cartilaginous callus was progressively replaced by bony callus by endochondral ossification and thereafter new bone was formed directly by intramembranous ossification. OPN mRNA was detected in preosteoblasts and osteoblasts at the boundary between fibrous tissue and new bone. ON, MGP, and OC mRNAs appeared early in the differentiation stage. The variety of cell types expressing mRNA encoding bone matrix proteins in distraction osteogenesis was much greater than that detected in the embryonic bone formation and fracture healing process. Moreover, the levels of OPN, ON, MGP, and OC mRNA expression markedly increased during the distraction phase. These results suggested that mechanical tension-stress modulates cell shape and phenotype, and stimulates the expression of the mRNA for bone matrix proteins.

Animals↗
PubMed1998

MRI evaluation of steroid- or alcohol-related osteonecrosis of the femoral condyle.

We reviewed 30 patients (46 knees) with steroid- or alcohol-related osteonecrosis of the femoral condyle. Their average age was 35 (14-61) years and the mean observation time was 7 (3-16) years. The medio-lateral extent and the anterior-posterior (AP) location of the necrotic lesion were evaluated on T1-weighted MRI and related to the collapse of the condyle. The size of the lesion was classified into three categories on the mid-coronal MRI of the femoral condyle: there were 44 small, 20 medium, and 9 large lesions. The condyle was divided into 3 zones: anterior, middle, and posterior. The location of the lesion was evaluated on the mid-sagittal image. There were 7 anterior, 9 middle, 29 posterior, 14 middle and posterior and, in 14 cases, all 3 zones were involved. 44 small lesions did not collapse, while 6/20 medium lesions and 5/9 large lesions collapsed. No lesion involving only one zone collapsed, while 4/14 lesions involving the middle and posterior zones and 7/14 lesions involving all three zones progressed to collapse. 4/6 condyles with large necrotic lesions involving all three zones collapsed. We conclude that the extent of the necrotic lesion on both the mid-coronal and mid-sagittal planes is of importance for the prognosis of osteonecrosis of the femoral condyle.

Adolescent↗
PubMed1998

Articular cartilage repair. Rabbit experiments with a collagen gel-biomatrix and chondrocytes cultured in it.

To repair a full-thickness articular cartilage defect in rabbit knees, we developed a technique of using a collagen gel hardened by cultured allogeneic chondrocytes in it. The gel-chondrocyte composite accumulated an intense metachromatic matrix, and had elasticity and stiffness enough to be shaped easily after 2 weeks' culture in vitro. It was implanted into full-thickness articular cartilage defects. Histologic evaluation was performed up to 6 months after surgery, using a histologic grading scale composed of 5 categories. In the gel-chondrocyte composite implanted group, good repair was observed from as early as 1 day up to 6 months. On the other hand, in the empty control group, no repair was observed 1 day to 2 weeks after the defects were made. At 4 weeks, some repair occurred, but even at 6 months the repair was not good.

Animals↗
PubMed1998

Long-term follow-up results of laminectomy for cervical myelopathy caused by ossification of the posterior longitudinal ligament.

OBJECT: This retrospective study was performed to assess the long-term results of cervical laminectomy in treating ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. METHODS: The authors reviewed medical records in 44 of 52 patients who underwent cervical laminectomy between 1970 and 1985 (mean follow up 14.1 years). The neurological recovery rate after laminectomy was 44.2% after 1 year and 42.9% after 5 years. The surgical outcome was maintained after 5 years but worsened between 5 and 10 years postsurgery: the recovery rate at the last follow-up review was 32.8%. Using multivariate stepwise analysis, the preoperative factors that affected clinical results were found to be the age at operation, the severity of preexisting myelopathy, and a history of trauma. Late neurological deterioration was observed in 10 (23%) of 44 patients. The earliest deterioration occurred at 1 year and the latest was at 17 years postsurgery (mean 9.5 years). The most frequent cause of deterioration was trauma due to a fall (six patients), followed by ossification of the ligamentum flavum (three patients). Postoperative spread of the OPLL was noted in 70% of the patients, but it was clearly the cause of neurological deterioration in only one of them. After laminectomy, postoperative progression of kyphotic deformity was observed in 47% of patients, but these changes did not cause neurological deterioration. CONCLUSION: The authors recommend early surgical decompression for OPLL because the outcome is better for younger patients and for those with a higher score as measured by the Japanese Orthopedic Association's system.

Accidental Falls↗
PubMed1998

Frequent mutations in the beta-catenin gene in desmoid tumors from patients without familial adenomatous polyposis.

Mutations in the APC gene contribute to development of sporadic desmoid tumors as well as to the hereditary tumors that usually accompany familial adenomatous polyposis (FAP). Adenomatous polyposis coli (APC) mutations cause an intracellular accumulation of beta-catenin that results in abnormal signaling in the wnt/wingless pathway. Mutations of the beta-catenin gene itself have also been noted in several types of tumors. In this study we screened the beta-catenin gene in 13 sporadic desmoid tumors for alterations in exon 3, which encodes several serine/threonine residues that are targets for phosphorylation by GSK-3beta. Somatic substitutions at codons 41 (threonine) and 45 (serine) were identified in seven independent tumors, respectively. Although no APC mutations were detected among the remaining six tumors, we found accumulation of beta-catenin by Western blotting analysis in one such tumor for which frozen tissues were available. Our results have suggested that possible involvement of beta-catenin activation by beta-catenin gene mutation or alteration of other factor(s) can contribute to desmoid tumorigenesis.

Adenomatous Polyposis Coli↗
PubMed1998

[Usefulness of thallium-201 myocardial scintigraphy during hyperventilation and accelerated exercise test in patients with vasospastic angina and nearly normal coronary artery].

The usefulness of thallium-201 (201Tl) myocardial scintigraphy was studied in 109 patients with vasospastic angina who had nearly normal coronary arteries (degree of stenosis < 50%). Coronary spasm was confirmed by pharmacologic agents in all 109 patients from January 1991 to June 1996. The appearance rate of visual redistribution on 201Tl myocardial scintigraphy was compared between four groups, 34 patients performing graded bicycle ergometer exercise starting at a work load of 50 W with increments of 25 W every 3 min [Ergo (3) group], 14 patients performing hyperventilation for 5 min [HV (5) group], 31 patients performing bicycle ergometer exercise with increments of 25 W every 1 min after 5 min hyperventilation [HV (5) + Ergo (1) group], and 30 patients at rest (Rest group). The value of the visual redistribution rate on 201Tl myocardial scintigrams in the HV(5) + Ergo (1) group (65%) was higher than that in the patients of other groups [Ergo (3) 41%, HV (5) 43%, Rest 33%]. However, there were no significant differences between the four groups. Stress 201Tl imaging after hyperventilation and accelerated exercise is useful to disclose ischemic evidence in about two thirds of patients with vasospastic angina and nearly normal coronary arteries, whereas about 40% of patients had visual redistribution on 201Tl myocardial scintigrams by performing standard procedures.

Acetylcholine↗
PubMed1998

Mutation of the p53 gene in postradiation sarcoma.

Radiotherapy is known to cause secondary malignancies in the radiation field; postradiation sarcomas (PRS) are one example of such malignancies. Little is known about the genetic changes, including p53 gene alterations, that are thought to play a role in the tumorigenesis of human PRS. In the present study, p53 gene mutations were analyzed on paraffin-embedded specimens from 24 patients with PRS (4 men and 20 women) by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) followed by direct sequencing. The primary tumors of these patients were uterine cervical cancers in 14, breast cancers in 3, malignant lymphomas in 2, and others in 5. Total radiation doses ranged from 36 to 300 Gy (median, 60 Gy). The latent period between completion of radiation therapy and development of PRS ranged from 3 to 34 years (median, 10 years). Malignant fibrous histiocytoma was the most common PRS, accounting for 12 cases. PCR-SSCP revealed the aberrant mobility shifts of bands in 24 cases: 21 shifts in exon 5, 18 in exon 7, and 12 in exon 8. Direct sequencing of the SSCP product revealed a total of 58 mutations in 21 (88%) of 24 cases: 4 cases had a single mutation, 5 had 2 mutations, 5 had 3 mutations, 6 had 4 mutations, and 1 had 5 mutations. Although 31% of the mutations did not change an amino acid, every tumor had at least one mutation that did, which may have provided the selection pressure for expansion. The frequency of p53 gene mutation in sporadic soft tissue sarcomas was 20%. These findings highlighted the extraordinarily high frequency of p53 gene mutations in PRS. G:C to A:T transition at dipyrimidine sites was found in 14 (58%) of 24 cases. Collectively, these findings indicate that radiation is causative for soft tissue sarcomas via p53 gene mutations.

Adolescent↗