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Biomedical subjects

T Yamagami

Publications and source records attributed to T Yamagami.

At least 73 records · Page 4Linked to original sources
PubMed1999

Precision of quantitative ultrasound measurement of the heel bone and effects of ambient temperature on the parameters.

The goal of this study was to determine the magnitude of measurement error of a quantitative ultrasound (QUS) measurement system of the heel bone in a practical setting and to examine the effects of ambient temperature in the test room on QUS parameters. We assessed the intratest, intertest and interdevice coefficients of variation (CVs) for speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness in vitro using phantoms and in vivo using volunteers. The intratest CV was the smallest and the interdevice CV was the greatest for every QUS parameter. The intertest CVs in vivo were 0.50% for SOS, 2.53% for BUA and 4.38% for stiffness. The standardized precision error (sPE) of stiffness, however, was smaller than those of the other two parameters. The intertest sPEs in vivo of the QUS parameters were 2-3 times greater than that of the spine bone mineral density (BMD) as measured by dual-energy X-ray absorptiometry (DXA). Using an average of duplicate measurements for the representative value of a subject could improve sPE of the QUS parameters to around 2 times greater than that of spine BMD. We examined five phantoms each with the QUS system under the ambient temperature conditions of 10, 20 and 30 degrees C. The lower the room temperature, the greater the values of all the QUS parameters obtained. We then assessed the effect of the season on the QUS parameters in healthy five women. SOS and stiffness were significantly greater in February (room temperature, 12.6 degrees C) than in June (22.4 degrees C) by 0.74% and 3.2% of overall means, respectively, by 10.1% and 4.3% as a standardized difference, or by 0.422 and 0.214 in Z-scores. This difference was likely to be caused by the difference in heel temperature between the seasons. The precision of the QUS system was inferior to that of conventional DXA densitometry. We recommend that institutions using several QUS system devices throughout the year at various locations monitor the precision of each device, make duplicate measurements for a single subject, use the same device for each patient being followed, and control the heel temperature of subjects by keeping the test room temperature constant throughout the year.

Absorptiometry, Photon↗
PubMed1999

Four of five RAG-expressing JCkappa-/- small pre-BII cells have no L chain gene rearrangements: detection by high-efficiency single cell PCR.

Single cell PCR assays have been further developed that detect over 80% of all VkappaJkappa, VkappaRS, and VlambdaJlambda rearrangements at efficiencies between 70% and 90%. These IgL chain gene rearrangement assays were used with small pre-BII cells that develop in comparably high numbers in the bone marrow of wild-type, Ckappa-deficient, and JCkappa-deficient homozygous and heterozygous mice. In all of these mice, only 15%-25% of all small pre-BII cells carry VlambdaJlambda rearrangements. These results confirm that lambdaL chain gene rearrangements occur independently of kappaL chain gene rearrangement and expression. They also show that a large part of the small pre-BII cells that express the rearrangement machinery can develop without IgL chain gene rearrangements.

Animals↗
PubMed1999

Frequencies of multiple IgL chain gene rearrangements in single normal or kappaL chain-deficient B lineage cells.

PCR analyses of the kappaL chain locus in single B-lineage cells of wild-type, Ckappa-, or JCkappa-deficient homozygous or heterozygous mice often detect multiple in- and out-of-frame rearrangements at the kappaL and lambdaL loci. They are most frequent in small pre-BII cells and equally so in wild-type and kappaL chain-deficient cells. Hence, kappaL chain production appears not to inhibit secondary rearrangements. Around 20% of all small preBII cells express IgL chains in their cytoplasm. Cells with a first productive rearrangement on one allele are favored to enter the immature B cell compartment. Thus, allelic exclusion might be secured by control of accessibility of IgL chain loci for rearrangement and by rapid selection of cells with a fitting over those with a nonfitting IgL chain.

Alleles↗
PubMed1999

The relationship between lifestyle, social characteristics and obesity in 3-year-old Japanese children.

It has been observed that obese children receive genetic and environmental effects that are associated with them being overweight. With regard to the latter, lifestyles such as eating habits and physical activity have been focused on. In the present study, the social characteristics which would dominate their lifestyles were investigated as background variables. For this purpose, 9668 Japanese children aged three years who were all born in Toyama prefecture, Japan, in 1998, served as birth cohort subjects. For the comparison between obese (Kaup Index; mass in kg/(height in m)2 > or = 18) and nonobese (Kaup index < 18) children, irregular snack intake, physical inactivity and reduced sleeping hours were chosen as statistically significant obesity-related lifestyle indicators for the children. For social characteristics, family construction (expanded family with grandparents/nonexpanded family), main caregiver (mother/other), attending a nursery school (yes/no) and mother's employment (full-time worker/other) were chosen. These were significantly associated with the obesity-related lifestyles mentioned above using multiple logistic regression analysis adjusted for other variables of social characteristics as well as for gender and birth month (July-December/January-June). The two greatest population-attributable risk percentages were observed for mother as main caregiver (-36.5%) and attending a nursery school (-28.9%) for irregular snack intake. Therefore, these two social characteristics substantially reduced the number of children with irregular snack intake. On the other hand, the two social characteristics were reversed in children with reduced sleeping hours (population-attributable risk percentage of mother as main caregiver: 15.4%; attending a nursery school: 17%). In contrast with favourable effects on snack intake these social characteristics showed an adverse influence on the sleeping habits of children.

Child, Preschool↗
PubMed1999

Correlation of a defect of portal perfusion in the dorsal part of segment IV of the liver on CT arterial portography with inflow of the aberrant pancreaticoduodenal vein.

The correlation between an aberrant pancreaticoduodenal vein and a portal perfusion defect in the dorsal part of segment IV as demonstrated on CT arterial portography (CTAP) was investigated. 14 patients with non-tumorous defects of portal perfusion in the dorsal part of segment IV of the liver parenchyma, shown on CTAP underwent CT during pancreaticoduodenal arteriography. The defect on CTAP was shown as an enhanced area resulting from non-portal venous inflow in eight (57%) of 14 patients on CT during pancreaticoduodenal arteriography. In conclusion, the non-portal venous supply via an aberrant pancreaticoduodenal vein occasionally causes a defect of portal perfusion in the dorsal part of segment IV on CT arterial portography.

Aged↗
PubMed1999

Intrahepatic portosystemic venous shunt associated with a large abdominal tumour.

Intrahepatic portosystemic venous shunt (IPSVS) is relatively uncommon, and is usually associated with chronic hepatitis or cirrhosis. We present a case of IPSVS that was considered to be caused by increased blood flow from a large abdominal tumour. The characteristic intrahepatic haemodynamics were demonstrated by CT angiography.

Hepatic Veins↗
PubMed1999

Aberrant gastric venous inflow to the left lobe of the liver parenchyma adjacent to the falciform ligament.

Direct inflow of the aberrant right gastric vein independent of the portal venous system to the liver parenchyma is a well known cause of non-tumorous abnormalities on CT angiography. However, there have been no previous reports of aberrant gastric venous drainage as the cause of non-tumorous abnormalities in the left lobe of the liver parenchyma adjacent to the falciform ligament on CT angiography. We present a case of direct inflow of an aberrant gastric vein to this region of the liver, which influenced the non-tumorous enhancement shown by CT hepatic arteriography.

Angiography↗
PubMed1999

The cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CT during arterial portography.

OBJECTIVE: We investigated the cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CT during arterial portography (CTAP). MATERIALS AND METHODS: One hundred sixty patients who simultaneously underwent CTAP and CT during hepatic arteriography of the common hepatic artery formed the basis of our study. The frequency, site, and shape of nontumorous defects of portal perfusion in the hepatic hilum on CTAP and the findings on CT during hepatic arteriography were determined. In 13 patients in whom nontumorous portal perfusion defects were observed on CTAP, CT was performed during selective angiography via the gastric artery, pancreaticoduodenal artery, or both. RESULTS: Nontumorous defects of portal perfusion were detected in 49 regions in 33 of the 160 patients (dorsum of segment IV, n = 30; dorsum of the lateral segment, n = 11; segment I, n = 8). Of the 33 patients, 16 had two defects each. Of the 49 nontumorous defects of portal perfusion, 38 showed enhancement on CT during hepatic arteriography. In the 13 patients who underwent CT during selective arteriography, enhancement due to nonportal venous inflow was seen in 16 of the 19 areas of decreased nontumorous portal perfusion (dorsum of segment IV, nine of 11; dorsum of the lateral segment, four of five; segment I, three of three). CONCLUSION: The main cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CTAP is decreased portal inflow due to nonportal supply via the parabiliary venous system. Thus, such lesions were also enhanced at a high frequency on CT during hepatic arteriography.

Aged↗
PubMed1999

[Follow-up study on effects of height velocity and puberty onset on biochemical markers of bone turnover].

In order to clarify the factors which affect bone metabolism at a young age, we investigated the relationships among the change of biochemical markers of bone turnover, the height velocity (HV) and puberty onset in healthy Japanese children. One hundred and twelve children (61 boys and 51 girls) were recruited at the fourth grade level in the elementary school (9 years old) and followed for 6 years. Serum bone specific alkaline phosphatase (B-ALP), serum tartrate-resistant acid phosphatase (TR-ACP), urine hydroxyproline (Hyp) and urine calcium (Ca) were measured as the biochemical markers of bone turnover. Bone mineral density of calcaneus was also measured by ultrasound method at the first grade (12 years old) and the third grade (14 years old) of junior high school. Heights and weights of all subjects were measured every April and the HV were calculated between each year. Puberty onset was defined as the time when pubic hair appeared in boys and as the time when menarche started in girls by self-administered questionnaire. All the biochemical markers of bone metabolism except for urine Ca had a significant positive relationship with HV. The values of the markers were highest of the time when the HV was maximum. In girls, the values of the biochemical markers remained high before menarche and then decreased significantly within three years after menarche, suggesting that bone turnover changed rapidly from high turnover type to low turnover type after menarche. On the other hand, in boys, high turnover type remained for a few years after puberty onset. Bone mineral density of calcaneus by ultrasound method increased significantly in boys between the two years in junior high school, but the increase was unclear except for broadband ultrasound attenuation (BUA) in girls in the same period.

Acid Phosphatase↗
PubMed1999

Successful treatment of relapsed T-cell non-Hodgkin's lymphoma with allogeneic peripheral blood stem cell transplantation with double conditioning.

We report a patient with T-cell non-Hodgkin's lymphoma (NHL) who relapsed after treatment with relatively intensive third-generation chemotherapy, VACOP-B, and who was safely and effectively treated with allogeneic peripheral blood stem cell transplantation (allo PBSCT) with double conditioning. The first conditioning consisted of carboplatin and etoposide. Twenty-one days later, the second conditioning was performed with cytosine arabinoside, cyclophosphamide, and total body irradiation (AraC/Cy/TBI). Between the periods of the first and second conditioning, autologous (auto) PBSCT (4.4 x 10(5) colony-forming units granulocyte/macrophage (CFU-GM)/kg, 3.8 x 10(6) CD34+ cells/kg) was performed to rescue marrow aplasia after the first conditioning. After the second conditioning, allo PBSCT (2.1 x 10(5) CFU-GM/kg, 8.2 x 10(6) CD34+ cells/kg) was performed from a human leukocyte antigen-identical sibling. Marrow reconstitution after allo PBSCT was rapid. Grade I acute graft-vs.-host disease (GVHD) involving skin and chronic GVHD on the eye was observed. No severe transplantation-related complications occurred. With a follow-up of 22 months after allogeneic PBSCT, the patient is alive without evidence of the disease. This case shows that allo PBSCT with intensive double conditioning may become a new treatment strategy to achieve long-term disease-free survival for young NHL patients of resistant relapse with a great deal of tumor burden and invasion of lymphoma cells in bone marrow.

Adult↗
PubMed1999

[Development of a multiple side-hole sheath introducer for use in aortography].

We developed a multiple side-holed sheath introducer that can also be used as a catheter for aortography before selective arteriography of the pelvic organs or lower extremities, as an alternative to straight or pig-tail catheters, which were formerly used for aortography. Aortography using the multiple side holed sheath introducer provided good detection of arteries in 100% of 10 cases, without any complications or difficulties. Thus, the present sheath introducer can replace straight or pig-tail catheters, resulting in the more economical use of one catheter prior to selective arteriography.

Aortography↗
PubMed1998

Irregular regeneration of hepatocytes and risk of hepatocellular carcinoma in chronic hepatitis and cirrhosis with hepatitis-C-virus infection.

BACKGROUND: Hepatocellular carcinoma (HCC) commonly develops in patients with chronic hepatitis or cirrhosis of the liver caused by hepatitis-C-virus (HCV) infection. We prospectively studied whether irregular regeneration of hepatocytes is a risk factor for HCC in these patients. METHODS: 242 patients were enrolled after liver biopsy and followed up by ultrasonographic scanning every 3 months. We examined age, sex, platelet count, the diagnosis of cirrhosis or chronic hepatitis, liver-cell dysplasia, and irregular regeneration. We classified irregular regeneration as slight or severe, based on histological expression of pleiomorphism, anisocytosis, bulging, and map-like distribution of hepatocytes. FINDINGS: 37 of 63 patients with cirrhosis and 26 of 179 with chronic hepatitis were judged to have severe irregular regeneration. HCC was diagnosed in 33 of 63 patients with cirrhosis (29 had severe irregular regeneration) and 12 of 179 patients with chronic hepatitis (11 had severe irregular regeneration) during mean follow-up of 5.5 years (SD 4.1; range 1-16). Multivariate analysis with a proportional-hazards model showed severe irregular regeneration (relative risk 15.1 [95% CI 5.6-40.7], p<0.0001) and a diagnosis of cirrhosis (3.8 [1.7-8.2], p=0.0008) to be significant risk factors for HCC. Within the diagnostic categories, irregular regeneration was also significant (cirrhosis 6.8 [2.1-21.9], p=0.0014; chronic hepatitis 28.5 [2.9-276.4], p=0.0038). INTERPRETATION: We recommend that liver biopsy to look for irregular regeneration should be done in patients with HCV-related chronic liver diseases. Those with severe irregular regeneration should be followed up carefully.

Adult↗
PubMed1998

Psychotherapy, today and tomorrow: status quo of behavior and cognitive therapy and its efficacy.

This paper reviews the development of behavior therapy, its applications, and the characteristics that make this form of therapy unique and applicable to a wide range of problems. Behavior therapy started from learning theory. It has adopted other theoretical bases and produced numerous techniques as a result of efforts to apply its principles to clinical problems. Recently, cognitive techniques of behavior therapy have been growing. The characteristics of behavior therapy are: (i) problem oriented and practical; (ii) emphasis on real life and living skills; and (iii) concrete viewpoint and techniques. These characteristics enable wide application. Today, many studies show the superior efficacy of behavior therapy for various mental and physical problems. Some well-documented techniques can be performed by non-professionals. The techniques and the viewpoint of behavior therapy would be accepted widely in Pacific Rim countries in the future.

Asia, Southeastern↗
PubMed1998

Focal fatty change in segment IV of the liver occurring after gastrectomy.

In some cases, focal fatty change of the liver parenchyma has been attributed to local systemic venous inflow replacing the portal venous supply. However, no reports of focal fatty change in the dorsal portion of segment IV of the liver caused by direct inflow of an aberrant pancreaticoduodenal vein (APDV) through the parabiliary venous system (PVS) are available. We report a 60-year-old woman with focal fatty change in segment IV of the liver which occurred after gastrectomy with APDV shown on CT performed during selective gastroduodenal arteriography.

Fatty Liver↗
PubMed1998

Complete amino acid sequences of chitinase-1 and -2 from bulbs of genus Tulipa.

The complete amino acid sequences of tulip bulb chitinase-1 and -2 (TBC-1 and -2) were determined. The sequences of the TBC-1 and TBC-2 were solved by analysis of peptides derived by enzymatic digestions as well as by chemical cleavages with cyanogen bromide (CNBr), o-iodosobenzoic acid, and hydroxylamine. TBC-1 and TBC-2 both consisted of 275 amino acid residues and had molecular masses of 30,825 and 30,863, respectively. They shared 247 identical residues, that is 90% identity. Comparison of their sequences with that of gladiolus bulb class IIIb chitinase-a (GBC-a) showed that 63% of the residues of both TBC-1 and TBC-2 are identical to that of GBC-a. From these results, it was seen that TBC-1 and -2 are class IIIb chitinases. The characteristic difference in specific activity between TBC-1 and -2 was also discussed on the basis of their amino acid sequences.

Amino Acid Sequence↗
PubMed1998

Identification of the aspartic acid residue located at or near substrate-binding site of rye seed chitinase-c.

Carboxyl groups of rye seed chitinase-c (RSC-c) were modified with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and glycine ethyl ester (GEE) at pH 5.5 and 5 degrees C in the presence and absence of (GlcNAc)4. In the absence of (GlcNAc)4, 5.2 carboxyl groups were modified by 90 min-reaction and the chitinase activity was reduced to 2.0%, while in the presence of (GlcNAc)4, 4.6 carboxyl groups were modified and 72% of the activity was retained. To identify the carboxyl group protected by (GlcNAc)4 from the modification, RSC-c was first modified with EDC and GEE in the presence of (GlcNAc)4 and then radiolabeled with EDC and [14C]GEE in the absence of (GlcNAc)4. Analyses of the radioactive peptides from the tryptic and chymotryptic digests of radiolabeled RSC-c showed that the main radiolabeled carboxyl group is that of Asp95, suggesting that Asp95 is located at or near substrate-binding site of RSC-c.

Acetylglucosamine↗