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Biomedical subjects

Y Abe

Publications and source records attributed to Y Abe.

At least 199 records · Page 11Linked to original sources
PubMed2000

Indication of cystoscopy in patients with asymptomatic microscopic haematuria.

To establish the appropriate indication of cystoscopy in patients with asymptomatic microscopic haematuria, we reviewed 263 cases with positive reaction for urinary dipstick test on annual health screening examination. On initial examination, 18 highly significant lesions, 52 moderately significant lesions and 38 insignificant lesions were detected. No underlying lesion could be found in 96 patients and no microscopic haematuria in 59 patients. However, bladder cancers were detected in only 8 (3.0%) cases. All patients with bladder cancer were older than 40 years. These facts suggest that cystoscopy is not necessary for patients with a single microscopic haematuria and those younger than 40 years.

Adolescent↗
PubMed2000

Axillary lymph node metastases in patients with small carcinomas of the breast: is accurate prediction possible?

OBJECTIVES: To find out whether macroscopic classification of the tumour margin is predictive of axillary lymph node metastases and to identify a combination of clinical and pathological findings by which axillary node status can be predicted accurately in small carcinomas (T1) of the breast. DESIGN: Retrospective study. SETTING: Municipal referral centre, Japan. SUBJECTS: All 1003 patients with T1 invasive carcinoma of the breast who had axillary lymph node dissection between January 1970 and December 1996 as part of their treatment. MAIN OUTCOME MEASURES: The association between the incidence of axillary lymph node metastases and 10 clinical and pathological factors (age, palpability and size of tumour, macroscopic classification of tumour margin, clinical axillary status, radiating spiculation on a mammogram, histological type, lymphatic invasion, oestrogen and progesterone receptor status) were analysed. RESULTS: Clinical axillary node status, macroscopic classification of tumour margin, lymphatic invasion, and age of the patient were significant predictors of axillary lymph node metastases (p < 0.01 in each case). Among 47 patients aged 65 or more whose tumours had well-defined margins and with a clinical N0 status in the axillae, the incidence of histological axillary lymph node metastasis was only 6% (n = 3) whereas it was 65% in 57 patients with tumours of ill-defined margins whose axillae were N1 or N2. CONCLUSIONS: Macroscopic classification of tumour margins is an independent predictor of axillary lymph node metastases for patients with small carcinomas of the breast. However, even with combinations of the examined predictors of axillary node metastases, the subgroup of patients at minimal risk of metastasis was less than 5% in T1 breast cancer, whereas three-quarters of the patients had clear axillary lymph nodes. Most patients with T1 breast cancer will need surgical staging of the axillae by methods such as sentinel node biopsy.

Adult↗
PubMed2000

Thyroid hormones influence serum leptin levels in patients with Graves' disease during suppression of beta-adrenergic receptors.

Leptin is a protein product of the ob gene, mainly produced by adipocytes. Leptin is thought to play an important role in the homeostasis of body weight by suppressing appetite and increasing energy consumption. The aim of this study was to investigate the possible effect of thyroid hormone on the regulation of the leptin system during suppression of beta-adrenergic receptors in Graves' patients. We studied 15 adult female patients with Graves' disease. Thyroid function, serum levels of leptin, and percent body fat (%BF) were examined at four different clinical conditions during therapy (A, untreated; B, beta-adrenergic antagonist only [A, B; hyperthyroid], C, beta-adrenergic antagonist and antithyroid drug; D, antithyroid drug only [C, D; euthyroid]). The use of beta-adrenergic antagonist significantly reduced heart rate in spite of hyperthyroid state, indicating sufficient suppression of beta-adrenergic receptors. During treatment with beta-adrenergic antagonist, leptin percentage of body fat (%BF) ratio significantly decreased in euthyroid state compared to that in hyperthyroid state (from 38.7 +/- 21.3 to 18.1 +/- 19.3, p = 0.003). Moreover, there was a significantly positive correlation between delta leptin/%BF and delta free thyroxine (FT4) (r = 0.51, p = 0.008). Under a euthyroid state induced by antithyroid drug treatment, leptin/%BF did not change in spite of withdrawal of beta-adrenergic antagonist. Our data indicate that thyroid hormones could increase serum leptin level during suppression of beta-adrenergic receptors in Graves' patients. Our data also suggest that the beta-adrenergic action of thyroid hormones might be partly mediated by regulation of leptin.

Adrenergic beta-Antagonists↗
PubMed2000

Implications of p53 protein expression in experimental spinal cord injury.

In order to clarify the role of p53, known as a tumor suppressor protein and also as a key molecule of apoptotic cell death, we have studied p53 expression in relation to localization, time course, cell type, and TUNEL reaction in a rat model of transectional spinal cord injury. Other apoptosis related molecules, p21, Bcl-2 and Bax, that are in the cascade of p53 pathway, were also examined. p53 was expressed in cells residing in the vicinity of transection as early as 30 min. For the next 2 days, the positive cells spread in distribution, increased in number, and thereafter decreased. p53 immunoreactivity was localized primarily to the nucleus but not to cytoplasm. Double-staining with glial cell markers revealed that p53 immunoreactivity was often co-localized in microglia, oligodendrocytes and astrocytes, but not in neurons. In view of the results of the double-staining of p53 and Bcl-2, Bax or TUNEL, a variety of apoptosis-related molecules are expressed with p53, all within the first three days of injury. Further, the process of apoptosis via the p53, pathway appears complex even in this simple model of CNS injury. Our study suggests that the manipulation of these apoptosis-related molecules may prove useful in modifying the cell and tissue damage in traumatic CNS injury.

Animals↗
PubMed2000

Treatment with propylthiouracil is associated with appearance of antineutrophil cytoplasmic antibodies in some patients with Graves' disease.

The use of propylthiouracil (PTU) for the treatment of Graves' disease is associated with few adverse effects such as skin eruptions, liver dysfunction, and agranulocytosis. Furthermore, recent studies described the development of antineutrophil cytoplasmic antibody (ANCA)-related glomerulonephritis and vasculitis in patients treated with PTU. Here we investigated whether PTU therapy per se is associated with the appearance of ANCA in patients with Graves' disease. We analyzed 119 serum samples from 117 patients with Graves' disease treated with either PTU (n = 56), or methimazole (MMI) (n = 21), as well as untreated patients (n = 42). Myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA were tested by enzyme-linked immunosorbent assay (ELISA) kits. MPO-ANCA was negative in all patients treated with MMI therapy and untreated patients. However, MPO-ANCA was detected in 21 (37.5%) of 56 patients treated with PTU therapy. Furthermore, two patients who were negative for MPO-ANCA became positive after PTU therapy. The proportion of patients positive for MPO-ANCA increased with the prolongation of PTU therapy, but did not correlate with age, gender, and positive antithyroperoxidase (TPO) antibody. Among 21 MPO-ANCA positive patients, 12 had no symptoms, but 9 patients complained of myalgia, arthralgia, or common cold like symptoms after the appearance of MPO-ANCA. Three patients developed agranulocytosis or granulocytopenia, but none showed abnormal urinary findings. Our results suggest that PTU per se is associated with the production of MPO-ANCA in patients with Graves' disease.

Adult↗
PubMed2000

Thyroid-stimulating antibody is related to Graves' ophthalmopathy, but thyrotropin-binding inhibitor immunoglobulin is related to hyperthyroidism in patients with Graves' disease.

We investigated the relationship between thyroid function or ophthalmopathy of Graves' disease and thyrotropin receptor antibodies (TRAb) in 155 untreated patients with Graves' hyperthyroidism. All patients were examined by ophthalmologists, and underwent computed tomography of the orbit and measurement of serum free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin-binding inhibitor immunoglobulin (TBII), and thyroid stimulating antibodies (TSAb). Patients were divided into three groups according to the presence of orbital fat increase (OFI) and extraocular muscle enlargement (EME): 57 patients without OFI and EMO formed the no Graves' ophthalmopathy (NGO) group; 55 patients with OFI but without EMO formed the OF group; 43 patients with EME with or without OFI formed the EM group. The FT3, FT4, and thyroid weight increased in the order of the EME, NGO, and OFI groups. TSAb increased in the order of the NGO, OFI, and EME groups, and TSAb was significantly greater in the EME and OFI than in the NGO group. TBII was not significantly different among the three groups, but was lower in EME than NGO. There was a significant positive correlation between TBII and FT3 or FT4 in all patients combined as well as in all three groups, but correlation between TSAb and FT3 or FT4 was very weak in all groups, and that between TSAb and FT3 was not significant in the EM group In the relationship between ophthalmopathy and TRAb, the sum of the scores of eyelid swelling, proptosis, and extraocular muscle enlargement was taken as a measure of the overall severity of the Graves' ophthalmopathy (GO). TSAb was significantly correlated with the GO score, but there was no correlation between TBII and GO scores. In conclusion, TSAb was correlated with ophthalmopathy but TBII was related to hyperthyroidism.

Adipose Tissue↗
PubMed2000

Anaplastic changes associated with p53 gene mutation in differentiated thyroid carcinoma after insufficient radioactive iodine (131I) therapy.

Thirty-two patients with differentiated thyroid carcinomas with distant metastasis were examined using a radioactive iodine (131I) tracer dose prior to 131I therapy and followed up for 10 years or until death (whichever occurred first). Nineteen patients who received 131I therapy had an accumulation of 131I in the metastases (group I) and 15 of those patients were alive more than 10 years after the first 131I treatment. In contrast, all 13 patients in whom the metastases did not show accumulation of 131I died within 10 years. Of the latter group, eight patients had received 131I therapy (group II), four of whom died with anaplastic changes within 5 years of treatment. p53 gene mutation was identified by immunohistochemistry in primary thyroid carcinoma tissue from patients with anaplastic changes that were evident during total thyroidectomy. Five patients did not receive 131I therapy (group III), of whom one, who also had a p53 gene mutation in the original tumor, died with anaplastic change 10 years after thyroidectomy. Seven patients in group I had p53 gene mutations in their thyroid carcinoma tissues, but none showed anaplastic changes. Our results suggest that 131I therapy may be useful for patients with distant metastases, with or without p53 gene mutations, which show accumulation of 131I from tracer and therapeutic doses. In contrast, 131I therapy is apparently not effective in patients who do not show sufficient accumulation of 131I, but rather, may cause early anaplastic changes with a p53 gene mutation.

Adult↗
PubMed2000

Transforming growth factor-beta1 stimulates contraction of human glioblastoma cell-mediated collagen lattice through enhanced alpha2 integrin expression.

Rapid invasiveness is a feature of the highly malignant glioblastoma tumor and is closely related to patient prognosis. The interaction between extracellular matrix (ECM) and cell surface receptors such as integrin heterodimers play a key role in the process of tumor invasion. We investigated the effects of transforming growth factor-beta1 (TGF-beta1), which is a mitogenic factor for glial cells, on integrin expression in T98G human glioblastoma cells using an in vitro model 3-dimensional collagen lattice. Exogenously applied TGF-beta1 dose-dependently enhanced collagen lattice contraction. Among the inhibitory antibodies tested against alpha integrin subunits, the anti-alpha2 antibody, P1-E6, alone prevented the enhanced contractile response by TGF-beta1, whereas any alpha integrin antibody (including P1-E6) had little effect on lattice contraction when cultured without TGF-beta1. RT-PCR analysis revealed that TGF-beta1 strongly increased alpha2 integrin transcript level. Furthermore, pretreatment with antisense phosphorothioate oligodeoxynucleotides against human alpha2 integrin using hemagglutinating virus of Japan (HVJ) liposome-mediated transfer prevented the effects of TGF-beta1 and also reduced the lattice contraction even in the absence of TGF-beta1. This data indicates that increased expression of alpha2 integrin is responsive to enhanced collagen lattice contraction by TGF-beta1. We suggest that TGF-beta1 exerts its effects on the invasive property of glioblastoma cells via upregulation of the alpha2 integrin subunit expression.

Antigens, CD↗
PubMed2000

Characterization of the N-oligosaccharides attached to the atypical Asn-X-Cys sequence of recombinant human epidermal growth factor receptor.

The extracellular domain of human EGF receptor (sEGFR) produced by CHO cells has been used in various biophysical studies to elucidate the molecular mechanism of EGF-induced receptor activation. We have found that the CHO sEGFR contains one oligosaccharide chain attached to an atypical N-glycosylation consensus sequence, Asn(32 )-X( 33 )-Cys(34 ). The oligosaccharide structure at Asn(32 ) is a mixture of the monosialo and asialo forms of a core fucosylated biantennary complex-type oligosaccharide. Deletion of this atypical glycosylation site by replacement of Asn(32 ) with lysine changed neither the expression nor function of the full length EGFR in CHO cells. The glycosylation at Asn(32 ) in CHO sEGFR was incomplete: 20% of Asn(32 ) remained unmodified. Thus, CHO sEGFR itself is heterogeneous with respect to the glycosylation at Asn(32 ), which may cause problems in biophysical studies. An attempt to remove the oligosaccharide at Asn(32 ) enzymatically did not succeed under nondenaturing conditions. Therefore, sEGFR with the mutation of Asn(32) -> Lys(32 )is useful for biophysical and biochemical studies, and, particularly, for X-ray crystallography.

Amino Acid Sequence↗
PubMed2000

A role of insulin-like growth factor I for follicle-stimulating hormone receptor expression in rat granulosa cells.

The present study was undertaken to identify the mechanisms underlying the effect of insulin-like growth factor I (IGF-I) on FSH receptor (FSHR) in rat granulosa cells. Treatment with FSH produced a substantial increase in FSHR mRNA level, as was expected, while concurrent treatment with increasing concentrations of IGF-I brought about dose-dependent increases in FSH-induced FSHR mRNA, with a maximal response 2.8-fold greater than that induced by FSH alone. IGF-I, either alone or in combination with FSH, did not affect intracellular cAMP levels, whereas it enhanced the effect of 8-bromo (Br)-cAMP on FSHR mRNA production. Taken together, these findings suggest that the ability of IGF-I to enhance FSH action concerning the induction of FSHR is exerted at sites distal to cAMP generation. We then investigated whether the effect of IGF-I and FSH on FSHR mRNA levels was the result of increased transcription and/or altered mRNA stability. The rates of FSHR mRNA gene transcription, assessed by nuclear run-on transcription assay, were not increased by the addition of IGF-I. On the other hand, the decay curves for the 2. 4-kilobase (kb) FSHR mRNA transcript in primary granulosa cells significantly altered the slope of the FSHR mRNA decay curve in the presence of IGF-I and increased the half-life of the FSHR mRNA transcript. These data suggest a possible role for changes in FSHR mRNA stability in the IGF-I-induced regulation of FSHR in rat granulosa cells. Treatment with activin produced a substantial increase in FSHR mRNA level, as was expected, and concurrent treatment with IGF-I did not affect activin-induced FSHR mRNA. Our data suggest that the IGF-I effect on FSHR expression is related to cAMP production induced by FSH and may maintain FSHR mRNA level because of prolonged FSHR mRNA stability.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed2000

Effects of troglitazone on collagen accumulation and distensibility of aortic wall in prestage of non-insulin-dependent diabetes mellitus of Otsuka Long-Evans Tokushima Fatty rats.

We investigated the effect of troglitazone (TG) on aortic distensibility and histopathology at the preclinical stage in the non-insulin-dependent diabetes mellitus (NIDDM) model. Twenty male diabetic and 20 male nondiabetic rats were each divided into two groups: treated-DM, untreated-DM, treated-nonDM, and untreated-nonDM. TG (0.2%) was mixed in chow in the treated groups. From age 5 to 15 weeks, fast blood glucose and insulin were monitored. At 15 weeks, oral glucose tolerance test results, aortic wall histopathology, and collagen content were studied, and intravascular ultrasound images and aortic pressure were recorded. Aortic diameter was measured during the cardiac cycle, and the stiffness parameter beta was calculated. Blood glucose (mg/dl) 2 h after loading in treated-DM (139+/-20) was normalized (untreated-DM, 188+/-27; p<0.05). Insulin concentration (ng/ml) in treated-DM (3.2+/-0.4) was lower than that in untreated-DM (8.1+/-1.5; p<0.01). At 15 weeks, beta in untreated-DM (2.4+/-0.8) was larger than those in untreated-nonDM (1.5+/-0.4; p<0.0001) and in treated-DM (1.9+/-0.4, p = 0.0081). Aortic wall collagen (mg/g dry weight) increased in untreated-DM (32.8+/-3.3) as compared with treated-DM (28.1+/-3.8; p = 0.048). Histomorphometry showed decreased medial area (mm2) in treated-DM (0.55+/-0.05) compared with untreated-DM (0.78+/-0.12; p<0.0001). This study suggests that TG may prevent metabolic abnormalities and the deterioration of aortic distensibility at an early prediabetic stage.

Animals↗
PubMed2000

Diffusion over a saddle with a langevin equation

The diffusion problem over a saddle is studied using a multidimensional Langevin equation. An analytical solution is derived for a quadratic potential and the probability to pass over the barrier deduced. A very simple solution is given for the one-dimensional problem and a general scheme is shown for higher dimensions.

Journal Article↗
PubMed2000

Pancreaticobiliary ductal system: value of half-Fourier rapid acquisition with relaxation enhancement MR cholangiopancreatography for postoperative evaluation.

PURPOSE: To assess the usefulness of half-Fourier rapid acquisition with relaxation enhancement (RARE) magnetic resonance cholangiopancreatography (MRCP) for evaluation of postoperative changes in the pancreaticobiliary ductal system. MATERIALS AND METHODS: The study included 34 patients (20 men, 14 women; mean age, 65.5 years) who underwent surgery of the pancreaticobiliary ductal system. Half-Fourier RARE MRCP images were obtained after surgery. Qualitative evaluation included ratings by two observers for depiction of postoperative anatomy and for artifacts, as well as analysis of postoperative complications. Direct cholangiographic, computed tomographic, and ultrasonographic findings and 6-month follow-up results were the reference standard. Sensitivity, specificity, and accuracy were calculated for the evaluation of postsurgical complications seen at half-Fourier RARE MRCP. RESULTS: The sensitivity, specificity, and accuracy of MRCP for the evaluation of postsurgical complications were each 100% for ductal dilatation; 100%, 87%, and 89%, respectively, for choledochoenteric anastomotic stricture; 100%, 86%, and 87%, respectively, for pancreaticoenteric anastomotic stricture; 100% each for intraductal stones and anastomotic leakage; and 80%, 100%, and 94%, respectively, for cholangitis. CONCLUSION: Half-Fourier RARE MRCP is a reliable imaging technique for the evaluation of anatomy and of complications associated with a surgically altered pancreaticobiliary ductal system.

Adult↗
PubMed2000

Activation of the dorsal premotor cortex and pre-supplementary motor area of humans during an auditory conditional motor task.

Using functional magnetic resonance imaging (fMRI), we measured regional blood flow to examine which motor areas of the human cerebral cortex are preferentially involved in an auditory conditional motor behavior. As a conditional motor task, randomly selected 330 or 660 Hz tones were presented to the subjects every 1. 0 s. The low and high tones indicated that the subjects should initiate three successive opposition movements by tapping together the right thumb and index finger or the right thumb and little finger, respectively. As a control task, the same subjects were asked to alternate the two opposition movements, in response to randomly selected tones that were presented at the same frequencies. Between the two tasks, MRI images were also scanned in the resting state while the tones were presented in the same way. Comparing the images during each of the two tasks with images during the resting state, it was observed that several frontal motor areas, including the primary motor cortex, dorsal premotor cortex (PMd), supplementary motor area (SMA), and pre-SMA, were activated. However, preferential activation during the conditional motor task was observed only in the PMd and pre-SMA of the subjects' left (contralateral) frontal cortex. The PMd has been thought to play an important role in transforming conditional as well as spatial visual cues into corresponding motor responses, but our results suggest that the PMd along with the pre-SMA are the sites where more general and extensive sensorimotor integration takes place.

Acoustic Stimulation↗
PubMed2000

Effects of perindopril on left ventricular remodeling and aortic regurgitation in rats assessed by echocardiography.

This study investigated the effect of the angiotensin-converting enzyme (ACE) inhibitor perindopril on left ventricular (LV) remodeling and cardiac function in rats with aortic regurgitation (AR). Twenty male Sprague-Dawley rats in which AR was produced by closed-chest aortic valve puncture were divided into untreated and perindopril-treated (5 mg/kg/day) rats. Ten control rats were sham-operated. Blood pressure, body weight, and echocardiographic recordings were followed every 2 weeks for a period of 12 weeks. LV dimension (LVD) and fractional shortening (FS) were calculated. The heart was finally excised for weight, hydroxyproline measurements, and histopathology. At 12 weeks, end-diastolic LVD increased in untreated rats (10.8 +/- 0.2 mm) but did not dilate in treated rats (9.6 +/- 0.3 mm, p < 0.01 vs untreated rats). FS decreased from 6 weeks in untreated rats (27.3 +/- 0.9% at 12 weeks), but did not change in treated rats (33.8 +/- 0.5%, p < 0.001). The ratio of LV weight to body weight in untreated rats (2.62 +/- 0.11 mg/g, p < 0.05) was higher than in sham-operated rats (1.52 +/- 0.02 mg/g) and than in treated rats (1.95 +/- 0.07 mg/g). Interstitial collagen accumulation histopathologically increased in untreated rats and was inhibited in treated rats. LV collagen of untreated rats (1.46 +/- 0.08 mg/100 mg, p = 0.03) was higher than those of treated (1.08 +/- 0.09 mg/100 mg) and sham-operated rats (1.06 +/- 0.14 mg/100 mg). Perindopril inhibited LV remodeling induced by volume overload and preserved LV function in AR rats.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2000

Evaluation of L-glutamate clearance capacity of cultured rat cortical astrocytes.

Astrocytes have a function in the uptake of excitatory neurotransmitter L-glutamate via the glutamate transporter. To evaluate the L-glutamate clearance capacity of astrocytes, we developed a colorimetric method for the determination of L-glutamate concentration and measured changes in extracellular L-glutamate concentration in rat cortical astrocyte cultures. When L-glutamate (50-200 microM) was added to astrocyte cultures and incubated for 1-8 h, the extracellular L-glutamate concentration declined with time. When L-glutamate was mixed with astrocyte culture supernatants only, no significant change in L-glutamate concentration was observed, ruling out the possibility that L-glutamate is spontaneously or enzymatically degraded in the extracellular space. Alternatively, the time-dependent decline of extracellular L-glutamate concentration was blocked by the presence of glutamate uptake inhibitors, indicating that the glutamate uptake system of astrocytes plays a major role in the clearance of extracellular L-glutamate.

Animals↗