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Biomedical subjects

T Ohishi

Publications and source records attributed to T Ohishi.

At least 73 records · Page 4Linked to original sources
PubMed1994

Quantitative analysis of crosslinks pyridinoline and pentosidine in articular cartilage of patients with bone and joint disorders.

OBJECTIVE: To determine the content of two crosslinks, pyridinoline (a mature crosslink) and pentosidine (a senescent crosslink), in human articular cartilage, and to examine the effect of bone and joint disorders on the content of those crosslinks in articular cartilage. METHODS: After pretreatment with SP-Sephadex C-25, high-performance liquid chromatography was conducted on a hydrolysate of human articular cartilage from 53 patients with one of the following diseases: osteoarthritis (OA), rheumatoid arthritis (RA), osteoporosis, femoral head necrosis, and renal osteodystrophy (ROD). RESULTS: Pyridinoline levels were either unchanged with age or were slightly decreased in elderly patients. Pentosidine levels increased with age in the entire patient population. There was no significant difference in the pyridinoline content among the study groups, but there was a significant difference in pentosidine content (P < 0.001). ROD patients had the highest mean level of pentosidine (407 mumoles/mole of hydroxyproline), and RA patients had a higher mean level than age-matched OA patients (214 versus 103 mumoles/mole of hydroxyproline). CONCLUSION: Bone and joint disorders do not affect the pyridinoline content in articular cartilage, but they do not affect the pentosidine content.

Adult↗
PubMed1994

The effect of menopause on biochemical markers and ultrasound densitometry in healthy females.

Urinary pyridinoline (pyr) and deoxypyridinoline (dpyr) are new markers for bone resorption, and serum osteocalcin reportedly indicates osteoblastic activity. Recently, a new ultrasound bone densitometer instrument has been developed that measures ultrasonic properties of the os calcis, namely, the speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index. The effects of menopause on biochemical markers and ultrasound densitometry were investigated in 40 healthy females, 36-39 years, with regular menstruation, and in 117 healthy perimenopausal females, 47-57 years, who were divided into a premenopausal group and a postmenopausal group. Significantly elevated values of pyr, dpyr, and serum osteocalcin were found for the postmenopausal group as a whole compared with the premenopausal group. We examined postmenopausal groups 48-57 years of age stratified into 2-year intervals (within 2 years of the menopause, 2-4 years postmenopause and 4-6 years postmenopause). Elevated values of urinary pyr, dpyr, and serum osteocalcin were evident even in the first 2 years postmenopause compared with the premenopausal group, and these higher values were exhibited until 6 years after menopause. We found a significant decrease in SOS, BUA, and stiffness index of the postmenopausal group as a whole, compared with those of the premenopausal group. SOS, BUA, and stiffness index of the group within 2 years of menopause significantly decreased compared with those of the premenopausal group. The Z-scores of the increase in biochemical markers and the decrease in stiffness index in the postmenopausal group were approximately 0.7-1.3 compared with the premenopausal group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Urinary pyridinoline and deoxypyridinoline in prostate carcinoma patients with bone metastasis.

Bone metastases from prostate carcinoma are predominantly osteoblastic. Recently, urinary pyridinoline (Pyr) and deoxypyridinoline (Dpyr) have been employed as indicators of bone resorption. In this study, we evaluated urinary Pyr and Dpyr levels in 19 prostate carcinoma patients, of whom 12 had bone metastasis and seven had not, and 11 age-matched control subjects. There was a significant difference in Pyr levels between the control group and the patients with metastasis (mean +/- s.d., 19.5 +/- 7.2 vs 73.3 +/- 67.1 nmol mmol-1 creatinine, P < 0.05). The mean level of Dpyr in the patients with metastasis (10.8 +/- 8.0 nmol mmol-1 creatinine) was significantly higher than that in the control group (3.1 +/- 2.1 nmol mmol-1 creatinine, P < 0.01), and also higher than that in the patients without metastasis (3.5 +/- 1.9 nmol mmol-1 creatinine, P < 0.05). There was no significant difference in Pyr and Dpyr levels between the control group and the patients without metastasis. These results suggest that bone resorption is also accelerated in prostate carcinoma patients with bone metastasis.

Aged↗
PubMed1994

Two alternative pathways of transcription initiation in the yeast negative regulatory gene GAL80.

The yeast GAL80 gene, encoding a negative regulatory protein of galactose-inducible genes, shows both constitutive and galactose-inducible expression. The inducible transcription is under the control of Gal4p, a common activator for the galactose-inducible genes, which binds to an upstream activation sequence, called UASG, spanning between -105 and -89 in the 5'-flanking region of GAL80. Here we demonstrate that the constitutive transcription started at +1, whereas the inducible transcription occurs from a set of downstream sites at +37, +47, +56, and +67. Both transcriptions were enhanced 10-fold by another UAS, whose 5' boundary is located between -195 and -185. Gal4p stimulated transcription, which depends on the TATA box located at -20, from all the downstream sites. By contrast, the constitutive transcription depended on a small region of less than 16 bp long encompassing the +1 site, which directed transcription even in the absence of both the TATA box and the UASs. When a fragment covering that region was inserted immediately upstream of the open reading frame of HIS3, the resulting gene fusion, if introduced into a his3 yeast strain, supported growth on histidine-lacking medium. We detected by gel retardation assay a protein specifically interacting with this fragment. All the transcriptions observed in the in vivo experiments were faithfully reproduced in a cell-free transcription system. From these results, we suggest that initiation of GAL80 transcription involves two alternative pathways; one is initiator dependent, and the other is Gal4p regulated and TATA dependent.

Base Sequence↗
PubMed1994

[A survey on elderly patients' knowledge of management of health care].

We conducted a questionnaire survey on the awareness of elderly patients in our hospital concerning medical management. As to the recognition of their own diseases, patients aged 80 or older, showed a lower degree of understanding than those under age 80. The proportion of patients who wished to known about their diagnosis decreased with age, although no statistical significance was recognized. Those who wished to known about their diagnosis, even if it were malignant, reduced significantly depending on the increase in age. In addition, the proportion of patients who would not like to know their diagnosis, if it were malignant, increased significantly as age increased. Proportions of patients who wanted to know other information, such as prognosis, the aims, methods and results of medical examination, the methods and adverse effects of treatment, and the names, effects and side effects of drugs, also decreased significantly as age increased. However, there were no statistical significant differences in the proportion of answers between cases of malignant and non-malignant disease. These data show that elderly patients had more anxiety or fear about malignancy, and wished to know less about medical management than non-elderly patients.

Aged↗
PubMed1994

[Evaluation of colon diseases by using new method of extracorporeal ultrasonic examination during usual colon endoscopy].

Generally two types of ultrasonic colon examination method are carried out. One is extracorporeal ultrasonographic examination (US). And another is endoscopic ultrasonographic examination (EUS). US is technically easy but is difficult to take good image of colon diseases. EUS can give us good and sufficient informations. But it is technically difficult and gives much trouble to patients. During usual endoscopy, we have tried extracorporeal ultrasonic examination by filling de-aired water around the diseased colon area. With this new method, we could easily identify the disease and got much better picture than usual US. And this new method gave almost no trouble and pain to examinees in comparison with EUS.

Calcinosis↗
PubMed1993

The Maillard protein cross-link pentosidine in urine from diabetic patients.

The Maillard protein cross-link pentosidine is a fluorescent condensation product of lysine, arginine and ribose. It accumulates in human tissues with age, and the accumulation process is accelerated in the tissues of diabetic patients. Using SP-Sephadex C-25 in the pretreatment for HPLC, we examined levels of pentosidine in urine without hydrolysis (free form) and levels of pentosidine in urine after hydrolysis (total forms), from 23 diabetic patients and 21 control subjects. The mean percentages of the values of free form per total forms (+/- SD) were 89 +/- 15% in diabetic patients, 88 +/- 16% in control subjects and 89 +/- 15% in total populations of diabetic patients and control subjects. There was a significant correlation between the values of free form and total forms in diabetic patients (r = 0.983, p = 0.0001), in control subjects (r = 0.820, p < 0.02) and in total populations of diabetic patients and control subjects (r = 0.951, p = 0.0001). The mean level of pentosidine per mol creatinine (+/- SD) was significantly elevated in urine from diabetic patients as compared to the level in control subjects (8.8 +/- 4.3 mumol/mol creatinine vs 4.2 +/- 1.4 mumol/mol creatinine, p = 0.0001 in free form; 10.1 +/- 5.3 mumol/mol creatinine vs 4.7 +/- 1.4 mumol/mol creatinine, p = 0.0001 in total forms). These results demonstrate that urinary pentosidine, especially in free form, could be a useful marker for the assessment of diabetes and diabetic complications.

Aged↗
PubMed1993

Severity of osteoarthritis determined by radiographically measured width of the femoral and tibial condyles of the knee.

With osteophytes excluded, the width of the femoral and tibial condyles of 46 osteoarthritic knees in 31 patients was measured with standing anteroposterior radiographs. The ratio of femoral over tibial condylar width was smaller in the medial compartments in the knees with advanced osteoarthritis. This finding was interpreted to indicate that the tibial side widened as osteoarthritis advanced, a factor considered to be due to stress microfracture.

Aged↗
PubMed1993

Age-related changes of urinary pyridinoline and deoxypyridinoline in Japanese subjects.

Urinary pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) are commonly used as bone resorption markers because they are more sensitive to bone resorption than is urinary hydroxyproline. Age-related changes of urinary Pyr and D-Pyr were studied in 337 healthy females, aged 1 to 93 y, and 113 healthy males, aged 3 to 75 y. Levels of urinary Pyr and D-Pyr follow a characteristic pattern as one ages, with very high values during childhood decreasing to low baseline levels in adulthood between 20 and 49 y. Both values in the 0-19 y age group were significantly higher than those in the other age groups for both sexes. These values increased moderately but significantly in females in the 50-59 y age group compared to those in the 40-49 y age group (Pyr: 26.4 +/- 7.6 vs. 19.3 +/- 6.2 nmol/mmol creatinine, p < 0.05; D-Pyr: 7.7 +/- 2.4 vs. 5.6 +/- 2.2 nmol/mmol creatinine, p < 0.05). In contrast, these values stayed at low levels in the 50-59 y age group in males. The values of urinary Pyr and D-Pyr were significantly higher in females than in males in the 50-59 y age group (females vs. males--Pyr: 26.4 +/- 7.6 vs. 17.0 +/- 3.9 nmol/mmol creatinine, p < 0.05; D-Pyr: 7.7 +/- 2.4 vs. 4.7 +/- 1.2 nmol/mmol creatinine, p < 0.05). In our cross-sectional study, the values of urinary Pyr and D-Pyr increased in childhood (0-19 y), and in the early postmenopausal period (50-59 y). These 2 urinary markers reflect the age-related changes of bone resorption.

Adolescent↗
PubMed1993

[RI venography for retroperitoneal hematoma following anticoagulant therapy for IVC filter thrombosis].

We presented a case of massive retroperitoneal hematoma owing to anticoagulant therapy for IVC filter thrombosis. CT showed the hematoma as high density area. RI venography demonstrated the thrombosis and collateral veins, suggesting the sites of anticoagulant induced bleeding and resultant hematoma. We suppose that RI venography is useful for the follow-up study of the IVC filter inserted cases.

Aged↗
PubMed1992

Quantitative analyses of urinary pyridinoline and deoxypyridinoline excretion in patients with hyperthyroidism.

It is well established that bone turnover increases and bone resorption exceeds bone formation in patients with hyperthyroidism. Recently, urinary pyridinoline and deoxypyridinoline have been employed as indicators of bone resorption. In this study, urinary pyridinoline and deoxypyridinoline levels in fourteen female patients with untreated hyperthyroidism were measured and compared with levels in 134 healthy females. Values of urinary pyridinoline and deoxypyridinoline were significantly higher than in age-matched controls. Moreover, values of serum free triiodothyronine correlated with urinary pyridinoline (r = 0.769, p < 0.01), and urinary deoxypyridinoline (r = 0.799, p < 0.001) in patients with hyperthyroidism.

Adult↗
PubMed1991

In vitro and in vivo antitumor effects of murine monoclonal antibody NCC-ST-421 reacting with dimeric Le(a) (Le(a)/Le(a)) epitope.

A murine monoclonal antibody (MAb), NCC-ST-421 (IgG3), was raised by using a human gastric cancer xenograft St-4 as immunogen. Immunization was achieved by transferring immunocompetent normal BALB/c mouse spleen cells into BALB/c-nu/nu mice bearing St-4 tumors. Hybridomas were produced from spleen cells of the mice after rejection of the tumors and were screened for preferential reactivity with cancers on formalin-fixed paraffin sections, as described previously for establishment of MAb NCC-ST-439 (M. Watanabe et al., Jpn. J. Cancer Res., 76: 43-52, 1985). The immunobiological and immunochemical properties of the new MAb NCC-ST-421 are described here. The MAb is essentially directed to a structure with dimeric Le(a) (V4III4Fuc2Lc6Cer) epitope (Gal beta 1----3[Fuc alpha 1----4]GlcNAc beta 1----3Gal beta 1----3[Fuc alpha 1----4]GlcNAc beta 1----3Gal beta 1----4Glc beta 1----1 Cer). It cross-reacts with Le(a) but does not show any effect on Le(a)-positive RBC in vitro or on Le(a)-positive tissue loci in vivo. ST-421 strongly induced antibody-dependent cellular cytotoxicity using human peripheral blood leukocytes as effector cells with a variety of human tumor cells, using the short-term 51Cr release assay. It also showed striking complement-dependent cytotoxicity with a human complement source and was able to produce lysis of a variety of human cancer cell lines, supporting its observed ability to cause cytotoxic suppression of tumor growth in nude mice. In another series of experiments, i.p. injection of ST-421 completely inhibited growth of human tumor xenografts in nu/nu mice, and this inhibitory activity was closely dependent on expression of the dimeric Le(a) antigen on the cell surface. While Le(a) antigen was expressed in the kidneys of nu/nu mice, infusion of ST-421 in these mice did not cause histological change in kidney tissue. This finding suggests that the MAb does not damage normal cells or tissues which contain cross-reacting Le(a) antigen. These results demonstrate that ST-421 exerts a significant antitumor effect in vitro as well as in vivo, does not affect Le(a) antigen expressed on normal tissues, and therefore has potential application in therapy of certain types of human cancer which express the dimeric Le(a) antigen.

Animals↗
PubMed1991

Fluorophores from aging human articular cartilage.

Human articular cartilages of various ages were digested with collagenase, and the fluorescence of the digests was measured as a function of age. At acidic pH, all collagenase-treated fractions were found to contain two main fluorophores with fluorescence maxima at 395 and 385 nm (excitation at 295 and 335 nm, respectively). Each fluorophore was isolated from the hydrolysate and its structure was deduced from spectral and chemical data. The 395/295 nm fluorophore was identified as pyridinoline, which is one of the non-reducible cross-linkages in collagen. The 385/335 nm fluorophore was identical to pentosidine, which was isolated from human dura mater and characterized by Sell and Monnier in 1989. Our results showed that the amount of pentosidine per collagen in human articular cartilage increases linearly with age (r = 0.929, p less than 0.005), while the amount of pyridinoline per collagen remained constant and was not correlated with age (r = 0.20). On the other hand, the amount of pentosidine per pyridinoline increased exponentially during life (r2 = 0.839, p less than 0.05).

Adult↗
PubMed1990

Mechanism of action of parathyroid hormone-induced proteoglycan synthesis in the growth plate chondrocyte.

In the growth plate chondrocyte, parathyroid hormone (PTH) stimulates phosphoinositol 4,5 bisphosphate (PIP2) degradation, which results in the rapid production of inositol (1,4,5) triphosphate (IP3). IP3 induced the release of calcium from an intracellular store, which caused a rapid increase in the cytosolic ionized calcium concentration. Parathyroid hormone also induced a 30-50% increase in proteoglycan synthesis. Phorbol esters, which pharmacologically activate protein kinase C, resulted in a 70-80% increase in proteoglycan synthesis. Treatment of the chondrocytes with retinoic acid (0.2 microM) inhibited the parathyroid hormone and phorbol ester-induced increase in intracellular ionized calcium and the increase in proteoglycan synthesis. From this data we postulate that the stimulation of proteoglycan synthesis in growth plate chondrocytes by PTH is mediated by the breakdown of membrane phosphoinositides, which results in the production of IP3 and an increase in ionized intracellular calcium. It is suggested that the degradation of membrane phosphoinositides also results in production of diacylglycerol and, thereby, an activation of protein kinase C, which has a large stimulatory effect on proteoglycan synthesis. The increase in cytosolic calcium most likely acts synergetically with diacylglycerol to activate protein kinase C. Retinoic acid blocks the effect of PTH and phorbol ester-induced proteoglycan synthesis and may act through the inhibition of protein kinase C. The overall effect of PTH on the growth plate chondrocyte appears to be a stimulation of proteoglycan synthesis that is mediated by the degradation products of membrane phosphoinositides.

Animals↗
PubMed1990

[Nephrotoxicity of cefpirome sulfate in rabbits--single and multiple intravenous administration].

Nephrotoxic potential of cefpirome sulfate (CPR) was examined by single and multiple intravenous administrations to Japanese white male rabbits. In single administration studies, no nephrotoxic symptoms were observed at the dose level of 320 mg/kg of CPR or less. At the dose level of 500 mg/kg or more, nephrotoxic findings were noted in both CPR and cefazolin sodium(CEZ) groups, such as proteinuria, glucosuria, increase in serum level of urea nitrogen, creatinine and uric acid, and necrosis and calcification in the proximal tubular epithelium of kidney. Renal phenolsulfonphthalein(PSP) excretion was suppressed at the dose level of 500 mg/kg of CPR or more, and 2000 mg/kg of CEZ. In 14 and 21 days repeated administration studies, no nephrotoxic symptoms were observed at the dose level of 100 mg/kg of CPR and CEZ or less. At the dose level of 200 mg/kg of CPR or more, urinary and serum biochemical findings mentioned above were observed, and histopathological changes in the kidney described above were added in 400 mg/kg group. The similar nephrotoxic symptoms including histopathological changes of the kidney were observed in the groups of 100 mg/kg of cefaloridine(CER) and 200 mg/kg of CEZ. In addition, renal PSP excretion was suppressed in the group of 200 mg/kg of CEZ. The results would suggest that CPR is less nephrotoxic than CER and that the nephrotoxic potential of CPR is comparable to CEZ because CPR caused more severe renal failures in single administration study and less severe renal failures in multiple administration study than CEZ.

Animals↗