PubMed HealthSearch

Biomedical subjects

G Takada

Publications and source records attributed to G Takada.

At least 19 recordsLinked to original sources

Changes in right ventricular volume in early human neonates.

To evaluate changes in the right ventricular volume in early human neonates, twenty fullterm infants were examined at 2, 24 and 120 h of age by two-dimensional echocardiography. End-diastolic and end-systolic right ventricular volumes (RVEDV and RVESV, respectively) were calculated with a computer system based on the bi-plane Simpson's rule using the apical four chamber and parasternal short axis views. Then right ventricular stroke volume (RVSV), ejection fraction (RVEF), and the mean normalized systolic ejection rate were obtained. The inner diameter of the ductus arteriosus was also measured simultaneously. RVEDV increased significantly by 24 h of age, but remained constant thereafter. RVESV remained virtually unchanged from 2 to 120 h, resulting in a significant increase (36%) of RVSV at 24 h compared with that at 2 h. The mean normalized systolic ejection rate remained unchanged. There was a good correlation between RVEDV and RVSV (r = 0.83). All ductus arteriosus except three narrow ones was closed by 24 h of age. In conclusion, at 24 h of age, the significantly increased RVEDV was closely related to the increased RVSV, which might be induced by increased volume load to the right ventricle because of the closure of the ductus arteriosus.

Ductus Arteriosus

Active hypothalamic-pituitary-gonadal axis in an infant with X-linked adrenal hypoplasia congenita.

To evaluate the hypothalamic-pituitary-gonadal axis in an infant with adrenal hypoplasia congenita, we measured the serum levels of testosterone and performed a luteinizing hormone-releasing hormone stimulation test. The diagnosis was made because of the presence of a mutation, A300V, in the DAX-1 gene. The results demonstrated an active hypothalamic-pituitary-gonadal axis, with adult-level testosterone of 266 ng/dl on day 0, and maintenance of testosterone concentration in the 100 to 250 ng/dl range for 140 days as expected. The luteinizing hormone-releasing hormone lest was compatible with an active pituitary gland with a luteinizing hormone peak of 13.1 IU/L and a follicle-stimulating hormone of 5.0 IU/L We conclude that the DAX-1 mutation does allow a normal reproductive axis at birth. We speculate that sometime between infancy and puberty this mutation in the DAX-1 gene leads to an inability to activate the reproductive axis from its childhood suppression; thus puberty will not develop in this infant.

Adrenal Insufficiency

Heterogeneity of liver disorder in type B Niemann-Pick disease.

Patients with type B Niemann-Pick disease (NPD) are known to be complicated with varying degrees of prognosis-determining liver dysfunction. To see heterogeneity of the dysfunction histologically, we performed liver biopsies on three NPD patients from three different families, who were diagnosed by enzyme assay of acid sphingomyelinase (ASM) and analysis of the ASM gene. In a severe case, of a female patient in her childhood, the liver showed definite fibrosis despite her age. In contrast, in a very mild case, of an adult male patient, the liver showed little fibrosis, though the ballooning of hepatocytes and infiltration of foamy histiocytes were observed in the tissue. Three homo-allelic mutations (S436R, A599T, and S231P) were identified in the patients. Thus, various hepatic phenotypes in type B NPD were shown to be caused by the heterogeneity of liver lesions originating from different ASM gene mutations.

Adult

Effect of weight changes on serum transaminase activities in obese children.

To examine the effect of weight changes on serum transaminase activities, glutamic oxaloacetic and pyruvic transaminases (GOT/GPT), a 3-month observation of 110 obese outpatients treated by a mild regimen for obesity was carried out. Patients were divided into two major groups, group I (n = 73) and group II (n = 37), with or without persistent elevation of serum GOT/GPT (> 30 IU/L), and retrospectively classified into four subgroups according to weight changes: group A, weight loss > 5%; group B, weight loss of < 5%; group C, an increase of < 5%; group D, an increase > 5%. In group IA, the incidence of cases with normalization of serum GOT/GPT was 70% and was significantly greater than those of the other three subgroups, respectively (P < 0.01). The incidences of decreased serum GOT/GPT activities were observed corresponding to the degree of weight changes not only in group I (100-27%) but also in group II (100-33%). These facts indicate that a mild regimen for obese outpatients for 3 months, significantly improves serum transaminase activities in patients not only with weight reduction but also weight gain, and that fatty liver may be present even in obese children with normal serum transaminase levels. The normalization of serum GPT activity in patients with weight gain suggests the presence of another factor contributing hypertransaminasemia in pediatric obese patients.

Adolescent

Serum alanine aminotransferase activity in obese children.

To confirm the significance of the serum alanine aminotransferase (ALT) test for the diagnosis of fatty liver and to clarify the relationship between serum ALT activity and the duration of obesity, we analysed 310 obese young school children (195M, 115F), who were classified into three duration groups (1-3 y, 4-6 y, 7 + y), three age groups (6-7 y, 8-9 y, 10-11 y), and four obesity groups (weight excess: mild, 20-29%; moderate, 30-39%; severe, 40-49%; very severe, 50%). Seventy-seven patients with abnormal ALT test, > 30 IU/l, and 27 patients with normal ALT test were examined by ultrasound study to identify the fatty-fibrotic pattern of the liver. Abnormal results of the serum ALT test were found in 24% of all patients. The fatty-fibrotic pattern was identified in 64/77 (83%) patients with abnormal ALT test and in 5/27 (18%) patients with normal ALT test. The serum ALT test has a sensitivity of 0.92 for detecting the fatty-fibrotic pattern proven by ultrasound study. Frequencies of cases with abnormal serum ALT levels increased with the duration of obesity. In the shortest duration group, however, the frequencies of abnormal results in serum ALT test did not increase with advanced ages or the grades of obesity. In conclusion, the present study confirmed the usefulness of the serum ALT test for screening fatty liver, and showed that a longer duration of obesity is generally associated with the occurrence of fatty liver in a paediatric obese population. In young patients with mild obesity or a short duration of obesity, however, fatty liver or fatty fibrosis may develop. Early intervention should be made in the case of obese children.

Alanine Transaminase

Effect of anoxia on striatal monoamine metabolism in immature rat brain compared with that of hypoxia: an in vivo microdialysis study.

We examined in 5-day-old rats the effects of either anoxia or 8% hypoxia on extracellular monoamines such as dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), norepinephrine (NE), 5-hydroxytryptamine (5-HT), and 5-hydroxyindole-3-acetic acid (5-HIAA) using in vivo microdialysis and subsequent HPLC. After stabilization 64 animals were exposed to 100% nitrogen for 16 min and 40 animals to 8% oxygen for 128 min. Both anoxia and hypoxia produced acute increase in the striatal extracellular DA (anoxia: P < 0.001, hypoxia: P < 0.01). Especially in anoxia, DA levels increased transiently to 2000-times the basal levels and 6-times higher than those in hypoxia. NE also increased in both anoxia and hypoxia. DOPAC and HVA decreased during hypoxia (P < 0.01 and P < 0.001, respectively), while those in anoxia were unchanged. In anoxia, decrease tendency of their levels were in short duration and that of 5-HIAA was followed by gradual increase (P < 0.001). These data demonstrated that brief exposure to anoxia or hypoxia had significant influence on striatal monoamine metabolism in immature brain and the pattern of change of monoamine in anoxia was different from that in hypoxia.

3,4-Dihydroxyphenylacetic Acid

Effects of cardiac output on Doppler transmitral and transtricuspid flow velocity patterns in very low birth weight infants.

We studied effects of cardiac output on Doppler transmitral and transtricuspid flow velocities in 24 appropriate for gestational age premature infants. We measured peak flow velocity of early diastole (peak E) and atrial contraction (peak A), ratio of peak flow velocity of early diastole to atrial contraction (peak E/A), total flow velocity-time integral, the first third filling fraction, peak filling rate normalized to stroke volume, and deceleration time (DT). Cardiac output was calculated as the product of the aortic flow velocity-time integral, aortic valve area, and heart rate. The cardiac output increased significantly with advancing gestational age and body weight (r = 0.78 and 0.86, P < 0.01, respectively). With increasing cardiac output, the transmitral as well as transtricuspid peak E, peak E/A, and total flow velocity-time integral increased significantly without any change in the peak filling rate normalized to stroke volume, peak A, and deceleration time. The transmitral as well as transtricuspid peak E did not correlate with the heart rate. Although these results do not establish whether changes in ventricular relaxation process or in cardiac output is responsible for the progressive increase in the peak E and peak E/A. Unchanged peak filling rate normalized to stroke volume of the left and right ventricles suggest that changes in cardiac output with maturity is, in fact, one of the important contributory factors. This evidence should be borne in mind in interpreting ventricular diastolic filling as an index of ventricular diastolic function in premature infants.

Blood Flow Velocity

Identification and characterization of cellulose-binding domains in xylanase A of Clostridium stercorarium.

The xynA gene encoding a major xylanase of Clostridium stercorarium F-9 was sequenced. The structural gene consists of an open reading frame of 1533 bp encoding a protein of 511 amino acids with an M(r) of 56,519. XynA consists of a catalytic domain belonging to family G at the NH2-terminus and two direct repeats of about 90 amino acids with a short spacing at the COOH-terminus. The repeated sequences, CBDI and CBDII, were not homologous with amino acid sequences of the CBDs classified into families I to V. Nevertheless, XynA showed an affinity for insoluble cellulose such as Avicel. Binding of XynA to Avicel was strongly dependent on the concentration of the incubation buffer and was inhibited by Triton X-100. XynA bound to Avicel (2.4 nmol/g-cellulose) and acid-swollen cellulose (180 nmol/g-cellulose), suggesting that this enzyme has higher affinity for amorphous cellulose than for crystalline cellulose. Functions of CBDI and CBDII were investigated by constructing the mutant enzymes and evaluating the cellulose-binding ability of each of them. XynA4 lacking CBDI and XynA5 lacking CBDII bound to Avicel to a lesser extent than the parental enzyme XynA; but XynA6, devoid of both CBDs, did not bind at all, indicating that CBDI and CBDII each functioned independently as CBD in XynA and their binding capacity was additive. Although the Ruminococcus albus endoglucanase EgIV that was joined to CBDs of XynA acquired cellulose-binding ability, the substrate specificity of EgIV was not altered in the presence or absence of CBDs.

Amino Acid Sequence

Changes in left ventricular volume and systolic function before and after the closure of ductus arteriosus in full-term infants.

Using echocardiographic techniques, the change in left ventricular (LV) volume and its effect on systolic function were studied before and after the closure of ductus arteriosus in 18 full-term infants. Examinations were performed twice in each infant, within 6 h after birth and on day 5, and the patency of the ductus with left-to-right shunt was confirmed at the first examination by Doppler echocardiography. A biplane Simpson's rule method was used for volume measurements. The LV end-diastolic volume, stroke volume, and cardiac output were more than 1.3-fold before the ductal closure, and the ejection fraction showed the similar change. However, the mean normalized systolic ejection rate, an index of contractility, and heart rate showed no significant difference. The Frank-Starling curve was obtained from the relationship between the LV end-diastolic and stroke volumes, and the LV performance was operated at a higher level on that curve when the ductus was open. Our data indicated that LV cardiac output was significantly higher during the patency of the ductus arteriosus and that this high cardiac performance might depend more on the Frank-Starling response to the volume load through the ductus arteriosus than on the increase of LV contractility and heart rate.

Cardiac Output

Cytotoxic activity against tumour cells mediated by intermediate TCR cells in the liver and spleen.

Morphological and phenotypic characterization in previous studies has indicated that intermediate (int) T-cell receptor (TCR) cells or T natural killer (TNK) cells may stand at an intermediate position between NK cells and high TCR cells of thymic origin in phylogenetic development. In this study, a functional study on cytotoxic activity against various tumour targets was performed in each purified subset. When a negative selection method entailing in vivo injection of anti-asialo GM, antibody or anti-interleukin (IL)-2R beta monoclonal antibody (mAb) was applied, IL-2R beta 1 CD3 NK cells were found to have the highest NK activity while IL-2R beta 1 int CD3 (or TCR) cells had a lower level of the NK activity. High CD3 cells (freshly isolated) did not have any such activity. Sorting experiments further revealed that the NK function mediated by int CD3 cells was augmented when they were exposed to anti-CD3 mAb. anti-TCR alpha beta, or anti-TCR-delta mAb. This phenomenon was not observed in NK cells and high CD3 cells. More importantly, when anti-CD3 mAb (or anti-TCR mAb) was added to the assay culture, int CD3 cells became cytotoxic against even NK-resistant tumour (Fc gamma R-. Fas+) targets. Liver mononuclear cells or int CD3 cells exposed to anti-CD3 mAb for 6 hr showed an elevated level of perforin in their cytoplasms. The present results suggest that int CD3 cells are usually non-cytotoxic against various tumours but become functional after being stimulated via the TCR CD3 complex.

Animals

Doppler echocardiographic findings of indomethacin-induced occlusion of the fetal ductus arteriosus.

We present an unusual case of indomethacin-induced occlusion of the fetal ductus arteriosus, which occurred in one of twins. In fetal echocardiography, the characteristic findings, a to and fro regurgitation pattern at pulmonary valve and postvalvular dilation of the main pulmonary artery, were obtained in addition to right ventricular dilation and hypertrophy, tricuspid regurgitation, right atrium dilation, and pericardial effusion. This fetus developed fetal distress and was delivered by an emergency cesarean section at 35 weeks' gestation. We suggest that these fetal echocardiographic findings may be the end-stage signs of the fetal ductal occlusion as well as the signs for emergent delivery.

Adult

Relationships between clinical and histological profiles of non-familial idiopathic neonatal hepatitis.

Idiopathic neonatal hepatitis (INH) is a syndrome characterized clinically and histologically but there is little information concerning the relationship between the clinical features and histological findings. In the present study, sixty-two patients clinically diagnosed as non-familial INH were histologically classified into four groups according to a provisional definition based on predominant lesions and examination of their clinical features. Patients of cholestasis (n = 23) and giant cell hepatitis (GCH, n = 21) were most frequent (37% and 33%, respectively), and patients of fatty liver (n = 10) and hepatitis (n = 8) were less common (16% and 13%). The GCH group showed a dominance of male, low birthweight, older and breast-fed babies. The cholestasis group demonstrated a dominance of male, low birthweight, younger and bottle-fed babies. The hepatitis group had the highest frequencies of high-grade hepatomegaly and splenomegaly. Fifty six cases completely recovered. Two died of hepatic failure in early infancy and four had chronic liver diseases at the age of 12 months. The fatty liver group had the worst outcome. Histological features in non-familial INH were variable and typical giant cell hepatitis was seen in only one-third of patients. Characteristic clinical features in each histologically classified group may suggest heterogenous etiologies underlying non-familial INH.

Diagnosis, Differential

Relationship of feeding modality to clinical features in Japanese infants with idiopathic neonatal hepatitis of the non-familial form.

To clarify the relationship between idiopathic neonatal hepatitis and feeding type, that is, formula-milk feeding and breast-milk feeding, the medical records of 100 patients (68 male and 32 female babies) with idiopathic neonatal hepatitis of non-familial form referred to the medical centers of Akita University and Tohoku University during the past 18 years were reviewed. The patients were divided into two 9 year periods (1975-83 and 1984-92), and their clinical features were analyzed in terms of feeding type and sex. The number of patients enrolled decreased from 69 in the first half to 31 in the second half. The number of male patients dropped from 53 to 15, although the number of female patients (n = 16) remained the same in both 9 year periods. The frequency of formula-milk feeding significantly decreased in the second half (42/69 to 6/31, P < 0.01). Compared with the expected numbers of patients in the second half, calculated on the changes in the live birth population and feeding modality between the two halves, the actually enrolled numbers of patients in the second half were less in both the male and the formula-milk fed groups (x0.35 and x0.22), whereas the numbers of female and breast-milk feeding groups were close to the expected values (x1.26 and x1.08). When sex and feeding modality were combined, the formula-milk fed male group showed the lowest value (x0.10), and the breast-milk fed female group showed the highest value (x2.85). In conclusion, feeding type, especially in combination with gender, might be one causative factor in the occurrence of idiopathic neonatal hepatitis.

Breast Feeding

Prediction of adult height in healthy Japanese children.

Longitudinal records from 13,707 children (6749 boys and 6958 girls), aged 6-17 years, were fitted by a smoothing cubic spline function, and the factors influencing changes in height SD score (SDS) during puberty were analysed. Height SDS at 6 years correlated closely with final height SDS. However, short children at 6 years of age tended to increase their height SDS at final height, whereas tall children at the same age tended to decrease their final height SDS for children with the same prepubertal height, the later that pubertal maturation occurred, the greater was the final height achieved. As short children entered puberty relatively late and tall children entered puberty relatively early, height SDS tended to approach 0 SD during puberty. A prediction function obtained by multiple regression analysis using height SDS at 6 years, the percentage by which the child is overweight at 6 years, age at onset of the pubertal growth spurt (PGS) and height at onset of the PGS provides a reasonable model for the prediction of final height SDS without the need to estimate bone age.

Adolescent

An infant case of Ebstein's anomaly of the tricuspid valve with abnormal diastolic filling pattern of the left ventricle.

We report herein an infant case of Ebstein's anomaly with abnormal diastolic filling pattern of the left ventricle. We also compare the case with a comparable case without such abnormal filling pattern. The patient, who had pulmonary valve stenosis, patent ductus arteriosus and mild mitral regurgitation, underwent transventricular valvotomy at 30 days of age. Postoperative course was uneventful. Serial Doppler echocardiographic studies were performed at 2 hr, 40 days, and 52 days of age. Peak velocity and flow velocity-time integral of early diastole, and ratios of the peak velocities and velocity time integrals of the early diastole and atrial contraction were below the 95% confidence limits of the normal controls. Our case suggests that left ventricular diastolic dysfunction may exist in the Ebstein's anomaly when it is associated with mitral valve abnormality such as mitral regurgitation.

Diastole