Biomedical subjects

A Yamamoto

Publications and source records attributed to A Yamamoto.

At least 109 records · Page 6Linked to original sources

PubMed2001

Serum acid phosphatase as a tumour marker in giant cell tumour of bone.

The serum acid phosphatase value was examined in nine patients with giant cell tumour of bone. Five showed a high level of acid phosphatase, which fell to within normal limits after surgery. Although the remaining four patients showed a normal acid phosphatase level before surgery, the postoperative acid phosphatase level was lower than the preoperative level in each case. Therefore, it is strongly suggested that serum acid phosphatase is a useful tumour marker in diagnosing giant cell tumour of bone as well as in evaluating the efficacy of treatment.

Acid Phosphatase↗

PubMed2001

Soft-tissue haemangioma and periosteal new bone formation on the neighbouring bone.

Deeply situated soft-tissue haemangioma sometimes causes periosteal new bone formation on the neighbouring bone. The purpose of this study was to elucidate the aetiological factors for this phenomenon. We studied 25 patients with soft-tissue haemangioma on whom plain radiographs and computed tomography (CT) and/or magnetic resonance imaging (MRI) examinations were performed. We examined the presence or absence of periosteal new bone formation, haemangioma-bone distance, size of haemangioma and pain. Periosteal new bone formation was seen in 12 of 25 patients. In these 12 patients, the haemangioma was adjacent to the bone in 11 patients, while the haemangioma-bone distance was 4 mm in the other patient. In the remaining 13 patients who had no periosteal new bone formation, the haemangioma-bone distance was 5-27 mm. Pain in the former group was stronger than that in the latter group, the difference being statistically significant. There was no statistically significant difference in size of haemangioma between the two groups. Therefore, the main factor that induces periosteal new bone formation on the neighbouring bone was not the size of haemangioma, but the distance between the haemangioma and the bone.

Adolescent↗

PubMed2001

Spontaneous rupture of the pancreaticoduodenal artery possibly related to prior occlusion of the common hepatic artery: report of a case.

We report herein a case of spontaneous rupture of the pancreaticoduodenal artery (PDA) associated with obstruction of the common hepatic artery. A 68-year-old man was admitted to our hospital following the sudden onset of severe upper abdominal pain. Computed tomography revealed a large mass formation in the peritoneal cavity. Hemorrhagic shock rapidly developed during the initial evaluation, necessitating an exploratory laparotomy to be performed in the emergency room. This revealed a large hematoma in the retroperitoneal space, and a ruptured PDA was sutured. Postoperative angiography showed obstruction of the common hepatic artery and also suggested that the source of the bleeding was the PDA. Thus, a diagnosis of spontaneous rupture of a PDA aneurysm associated with occlusion of the common hepatic artery was made. Following this case report, we discuss the development of true aneurysms of the PDA and the treatment of ruptured true PDA aneurysms resulting in shock.

Aged↗

PubMed2001

Osteofibrous dysplasia of the ulna.

We experienced two patients with osteofibrous dysplasia of the ulna. Both of them showed typical radiographic findings of osteofibrous dysplasia, except for location. One patient underwent surgery at the age of 15 years to confirm the diagnosis histologically. Although the tumor recurred 5 months after the surgery, expansion of the lesion seemed to cease at the age of 25 years. In the other patient, the natural course was observed. The tumor showed a tendency toward spontaneous regression at the age of 11 years. Therefore, the nature of osteofibrous dysplasia in the ulna seems to be the same as that in the tibia and fibula. Surgery must be delayed for as long as possible in osteofibrous dysplasia of the ulna, as well as that of the tibia and fibula.

Adolescent↗

PubMed2001

Resorption of synthetic porous hydroxyapatite and replacement by newly formed bone.

Synthetic porous hydroxyapatite (HA) is commonly used as a bone substitute for bone defects which, previously, would have been treated by autogenous bone grafting. HA has been thought to be a nonbiodegradable material that remains as it is implanted. However, after long-term follow-up, some authors report that the margin of implanted HA blocks or granules is absorbed, suggesting that HA is biodegradable. We experienced a patient in whom synthetic HA blocks implanted in a bone defect of the ilium after the harvesting of full-thickness bone for grafting were extensively absorbed and replaced by newly formed bone 6 years and 7 months after the implantation. Therefore, we conclude that HA is biodegradable. Sintering temperature, porosity, and pore diameter seem to influence the biodegradability of HA.

Absorption↗

PubMed2001

Uptake of oxidized low-density lipoprotein in a THP-1 cell line lacking scavenger receptor A.

We previously isolated THP-1 subtype cells (sTHP-1), a cell line that expresses scanty amounts of scavenger receptor A (ScR-A) and does not undergo foam cell formation when incubated with acetylated low-density lipoprotein (Ac-LDL). In this study, we investigated the accumulation of esterified cholesterol in sTHP-1 cells incubated with oxidized LDL (Ox-LDL), a physiologically modified lipoprotein in human. While sTHP-1 cells incubated with Ac-LDL accumulated only small amounts of esterified cholesterol, those incubated with Ox-LDL accumulated amounts similar to those accumulated by parent THP-1 (pTHP-1) cells. sTHP-1 cells expressed CD36 in amounts similar to the amounts expressed by pTHP-1 cells, and Ox-LDL was internalized through this CD36. The amount of accumulated esterified cholesterol was 73-81% of that accumulated in pTHP-1 cells expressing ScR-A. The levels of 125I-Ox-LDL binding, association, and degradation in sTHP-1 cells were 64-70% of the corresponding levels in pTHP-1 cells. In our experiments utilizing ScR-A-deficient sTHP-1 cells and a specific antibody against human CD36, most of the Ox-LDL interacted with the CD36 receptor. In addition, a substantial amount of Ox-LDL (28-42%) was bound and degraded by sTHP-1 macrophages when both of the two major scavenger receptors, ScR-A and CD36, were deficient or blocked. These results indicate that CD36 in macrophages plays an important role in foam cell formation by Ox-LDL, while additional scavenger receptor(s) may take part in significant pathways of Ox-LDL uptake in macrophages.

Blotting, Northern↗

PubMed2001

Ganglion cyst in the ligamentum flavum of the cervical spine causing myelopathy: report of two cases.

BACKGROUND: Ganglion cyst in the ligamentum flavum is commonly found in the lower lumbar region; occurrence in the cervical region is extremely rare. We report two cases of ganglion cyst in the cervical region and the clinical, pathological, and radiological findings. METHODS: The first patient was an 81-year-old man who was admitted to our hospital with gradually progressive gait disturbance and radiating pain in both arms and legs, which was dominant on the left side. The second patient was a 65-year-old man with progressive muscle weakness of the extremities who was admitted with radiating pain in the right arm. In both cases, the cervical spinal cord had been compressed by the cystic mass with degeneration of the ligamentum flavum (the former left, the latter right) at the level of C3-4. RESULTS: The extradural-intraspinal cystic masses, which were revealed by computed tomography (CT) and magnetic resonance imaging (MRI) to be situated antero-laterally to the cervical laminae, were removed surgically without difficulty. After surgery, the symptoms and neurologic signs improved in both cases. CONCLUSIONS: Ganglion cyst in the ligamentum flavum of the cervical spine is a very rare lesion causing radiculo-myelopathy. In both our cases, a correct diagnosis could be established preoperatively based on CT myelogram and MRI findings, and the results of surgery were excellent.

Aged↗

PubMed2001

Novel cell lines established from a human myxoid malignant fibrous histiocytoma arising in the uterus.

Two cell lines (Nara-H and Nara-F) with different phenotypes were established from a myxoid MFH of the uterus. In vitro, Nara-F grew in sheets showing a storiform arrangement and Nara-H in raised colonies. Although tumors generated in nude mice shared similar morphological features of abundant myxoid tumor in Nara-H and -F, the pleomorphic component was conspicuous in Nara-F. Both cell lines produced hyaluronic-acid but CD44 was expressed only in Nara-H. Estrogen receptor alpha (ER alpha) and progesterone receptor (PgR) were detected in Nara-H. Nara-F was positive for ER beta and PgR. Among hormonal agents, the response to the anti-estrogen tamoxifen was more sensitive than progesterone agents. This report illustrates the characteristics of these newly established cell lines, and presents the possibility of an adjuvant hormonal therapy for MFH.

Aged↗

PubMed2001

Leg edema, ST-T abnormalities, and high BNP values are important signs of heart failure in the elderly.

This study was aimed at the mechanism of the circulatory failure characteristic of the elderly through elucidating the cause of leg edema frequently found in patients under treatment in health care facilities for physical or mental handicaps. ECG and measurement of atrial (ANP) and brain (BNP) natriuretic peptides were carried out on 156 patients (mostly females aged 84 years on average) and echocardiographic assessment was done on 44 patients. Non-specific ST-T abnormalities were frequently found in patients with moderate or severe leg edema (61 vs. 37% in those with slight or no edema). BNP levels were markedly increased in patients with either leg edema or ECG abnormalities (Group B) and with both (Group C) compared with those without either (Group A), with averages of 35.5+/-23.9, 91.3+/-80.1, and 184.3+/-139.0 pg/ml, respectively, for Group A, B, and C. UCG examination revealed marked regurgitation of cardiac valves, more frequently in patients with BNP over 50 pg/ml than in those with less (14/24 vs. 2/20), with a difference in extent of 5.7 versus 1.6 on an arbitrary scale. In addition to left ventricular hypertrophy, dilatation of the left atrium and inferior vena cava was frequently observed in patients with higher BNP levels. It is concluded that both cardiac valve regurgitation and myocardial damage represented by ST-T abnormalities on ECG result in heart failure characteristic of the elderly, and that an increase in BNP is an important sign of such heart failure.

Journal Article↗

PubMed2001

Identification of mutans streptococcal species by the PCR products of the dex genes.

A pair of polymerase chain reaction (PCR) primers was designed on the basis of the nucleotide sequence homology of dextranase genes (dex) of Streptococcus mutans, S. sobrinus and S. downei. The primer pair amplified a 530-bp DNA fragment on the dex genes of mutans streptococcal species: S. mutans, S. sobrinus, S. downei, S. rattus and S. cricetus. HaeIII digestion of the 530-bp fragments generated species-specific subfragments, which were easily distinguishable from each other by agarose gel electrophoresis. These results suggest that the PCR-amplification of the dex gene followed by the HaeIII digestion is useful for rapid identification of the five species of mutans streptococci.

Animals↗

PubMed2001

FcgammaRIII b and FcgammaRIIa polymorphism may affect the production of specific NA1 autoantibody and clinical course of autoimmune neutropenia of infancy.

We studied 18 children with autoimmune neutropenia (AIN) to evaluate whether there was a possible relationship between the specificity of granulocyte autoantibodies (anti-NA1,2) and the phenotype of the NA system. Direct granulocyte immunofluorescence test (D-GIFT) was positive in all patients, and indirect granulocyte immunofluorescence test (I-GIFT) was positive in 17 of these 18 patients, respectively. Fourteen of 18 patients showed preferential binding to neutrophils from NA(1+2-) phenotyped donors. Immunoblotting with anti-FcgammaRIIImAb showed that IgG prepared from 7 of 12 patients precipitated both FcgammaRIIIb from NA1 and NA2 neutrophil lysate, whereas the other 5 precipitated only NA1. Patients' IgG did not react with purified FcgammaRIIa. FcgammaRIIIb genotype were NA(1+2-) in 15 of 18 patients and NA(1+2+) in the other 3. FcgammaRIIa type of all patients were (H+R-). These distributions were significantly different from those of healthy Japanese blood donors (n = 608). The genotype of FcgammaRIIIb and FcgammaRIIa may affect the production of neutrophil specific auto-antibodies in AIN of infancy and influence its clinical course.

Age of Onset↗

PubMed2001

Serum eosinophil derived neurotoxin may reflect more strongly disease severity in childhood atopic dermatitis than eosinophil cationic protein.

Serum levels of eosinophil cationic protein (ECP) have been shown to be a good parameter of the disease severity of patients with atopic dermatitis (AD). However, the relationship between the disease severity and the eosinophil derived neurotoxin (EDN) has not been established in AD patients. The purpose of this study is to examine serum ECP and EDN levels in relation to the disease severity in AD children. Serum ECP and EDN levels were assessed in relation to the skin scores in 34 AD children (18 boys and 16 girls; age 0.6 to 7years: mean+/-S.D. 2.2+/-1.9) and six non-atopic control children (three boys and three girls; age 1 to 3years: mean+/-S.D. 1.7+/-0.9). Serum ECP and EDN levels of the patients with AD were significantly increased compared with the non-atopic controls. Serum EDN levels of the patients were also related to the disease severity. The skin scores were more significantly correlated with serum EDN levels than ECP levels. We concluded that serum EDN may reflect more strongly disease severity as eosinophilic activation in AD children than serum ECP.

Biomarkers↗

PubMed2001

Advanced technique for three-dimensional visualization of compound distributions in a rice kernel.

A three-dimensional (3D) visualization technique for the compound distribution in a rice kernel was developed. This technique is a combination of sectioning, staining, and digital image postprocessing. By using a special microtome system with adhesive tapes, a set of sequential sections of a rice kernel, which can be preserved with their own set of relative position data, was obtained. A single set of sequential sections was stained by various chemical techniques for the visualization of protein, starch, or lipid content. Each stained section was digitally captured using a CCD imaging device. As the stained areas represent areas containing dye-target complex, the distribution of each compound in the section was visualized in two dimensions. The digitally captured images of a single set of sequential sections were reconstructed to produce a 3D plotting image. As a result, the distributions of various compounds in a rice kernel could be visualized in a new 3D model.

Coloring Agents↗

PubMed2001

Increased serum nitrate levels in infants with atopic dermatitis.

BACKGROUND: The pathogenesis of atopic dermatitis (AD) is still unknown. A recent study has shown that inducible nitric oxide synthase (iNOS) is expressed in the atopic skin lesion, suggesting the involvement of nitric oxide in the skin inflammation of AD. The purpose of the study was to examine serum nitrate (NO3) levels in relation to the disease severity in children with AD. METHODS: Serum nitrate levels were assessed in relation to the skin scores in 88 patients with atopic dermatitis (AD) (aged 0.4-8 years: mean+/-SD, 2.2+/-1.9, 41 boys and 47 girls) and 12 nonatopic children (aged 0.8-4 years: mean+/-SD, 1.8+/-0.9, seven boys and five girls). RESULTS: Serum nitrate levels of patients with AD were significantly increased as compared to nonatopic controls and were also correlated with the disease severity. The skin scores were significantly correlated with serum nitrate levels as well as peripheral eosinophil counts. CONCLUSION: Our results indicate that nitric oxide may be involved in the pathogenesis of vasodilation and erythema in AD skin.

Administration, Topical↗

PubMed2001

Screening of ischemic heart disease with cavernous artery blood flow in erectile dysfunctional patients.

Erection is a hemodynamic event and accordingly, erectile dysfunction (ED) is closely related with ischemic heart disease. We should confirm that the cardiac condition of the ED patient is safe enough to perform sexual intercourse prior to beginning treatment for ED. Asymptomatic ischemic heart disease cannot be diagnosed only in an interview, but it's difficult to perform cardiac exercise tests on all patients complaining of ED. Therefore, screening methods to evaluate patients who should undergo exercise tests are needed. Sixty patients with erectile dysfunction participated in this study. Physical examinations, interviews, and color Doppler examinations were conducted. Chest X-rays and electrocardiograms of all patients in the resting position were obtained, as were electrocardiograms following exercise. Echocardiograms, treadmill test results, thallium exercise scintigrams, and coronary angiograms were obtained as required for diagnosis. Two patients were excluded because they had obvious arteriogenic ED due to perineal injury. Fifty-eight patients underwent Doppler evaluations of their cavernous arteries and heart exercise tests. Fourteen patients (24.1%) were diagnosed with ischemic heart disease. Although six of them had already been diagnosed with ischemic heart disease, eight were newly diagnosed by the exercise tests. Cardiovascular risk factors such as advanced age, hyperlipidemia, diabetes mellitus, hypertension, smoking, and obesity were not sufficient predictive factors. The mean peak systolic velocity of the patients without ischemic heart disease was 34.6 cm/s vs 22.0 cm/s in those with ischemic heart disease. Only 3.7% of patients whose peak systolic velocity in the cavernous artery was equal to or exceeded 35 cm/s had ischemic heart disease. On the other hand, 41.9% of patients with peak systolic velocity of less than 35 cm/s had ischemic heart disease. The sensitivity of peak systolic velocity against ischemic heart disease was 92.9%, and specificity was 59.1%. In ED patients, incidences of complications involving symptomatic or asymptomatic ischemic heart disease were found to be high. The peak systolic velocity in the cavernous artery is thought to be a useful predictive factor of ischemic heart disease in ED patients. When a patient reveals a peak systolic velocity of less than 35 cm/s, he should undergo heart exercise tests prior to treatment of ED.

Adult↗

PubMed2001

Spring balance evaluation of the ischiocavernosus muscle.

We studied the voluntary contractile activity of the ischiocavernosus muscle (ICM) in 21 sexually potent and 97 erectile dysfunction (ED) subjects using a spring balance. A strap was placed around the coronal grove of the glans penis and tensioned with the spring balance. Subjects were asked and encouraged to contract the ICM against the spring balance. We evaluated the length of stroke, duration of contraction, and maximum contractile force. The length of stroke, duration of contraction, and maximum contractile force showed statistically significant differences between potent and ED subjects. Diagnosed psychogenic ED and arteriogenic ED showed higher contractile activity than cavernous ED and neurogenic ED. Our results corresponded to those of previous studies that have urged consideration of the role of the ICM during the process of erection in animal experiments and in human electrophysiological studies. The spring balance evaluation is a useful, inexpensive method for evaluating the ICM.

Adolescent↗

PubMed2001

Characteristics of a column suitable for capacity gradient chromatography with a borate eluent.

In capacity gradient elution, the gradient separation of ionic species is achieved by decreasing the ion-exchange capacity of a column during the course of the separation. Diol-type hydroxy groups on the resin surface form anionic complexes with borate as an eluting reagent. Thus, a chemically bonded anion-exchange column enriched with residual hydroxy groups allows the creation of a capacity gradient. An increase in the amount of the complex formed gradually brings about a decrease in the ion-exchange capacity of the column, and strongly bound analyte ions are eluted. We investigated the characteristics of a column suitable for this eluent system. The concentration of borate eluent required to remove the ion-exchange capacity depended inversely on the ratio of the residual hydroxy groups to functional groups. On a column in which this ratio was approximately 100, the ion-exchange capacity could easily be adjusted by using a low concentration of mannitol as a competing reagent. Use of this column led to very small baseline shifts during the borate-mannitol gradients, and to the simultaneous determination of anions with widely varying retention times.

Borates↗

PubMed2001

Effect of radical retropubic prostatectomy on erectile function, evaluated before and after surgery using colour Doppler ultrasonography and nocturnal penile tumescence monitoring.

OBJECTIVE: To assess the effect of radical retropubic prostatectomy on erectile function, by evaluating objectively patients' erectile function before and after surgery. PATIENTS AND METHODS: The study comprised 126 patients with clinically localized prostate cancer who were scheduled to undergo radical retropubic prostatectomy. After giving informed consent for the study, 123 patients underwent intracavernosal injection tests, colour Doppler ultrasonography and nocturnal penile tumescence monitoring before and after surgery. RESULTS: From the intracavernosal injection tests and nocturnal penile tumescence monitoring, 21 patients (17%) were evaluated as having normal erectile function before surgery. After radical retropubic prostatectomy, nine (43%) of these 21 potent men had preserved erectile function. In eight patients whose neurovascular bundles were preserved, five were potent after surgery. The cause of erectile function after surgery was a neurogenic disorder in seven and a related vascular disorder in five. CONCLUSION: From objective tests of erectile function on patients scheduled to undergo radical prostatectomy, 17% had normal erectile function. However, even after nerve-sparing radical retropubic prostatectomy, the proportion retaining potency was unsatisfactory. Although a neurological disorder was the main cause of erectile dysfunction after surgery, vascular disorders were also important.

Aged↗