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Biomedical subjects

S Era

Publications and source records attributed to S Era.

At least 19 recordsLinked to original sources
PubMed1992

Proton nuclear magnetic resonance studies on water structure in peritumoral edematous brain tissue.

Spin-lattice relaxation times (T1) of water protons and cross-relaxation times (TIS) between irradiated protein and water protons were measured to study the water structure in peritumoral edematous brain tissue of rats. Despite small changes in T1, water, and electrolyte contents, TIS values of water protons were significantly reduced in peritumoral edematous brain tissue when compared to those of the controls. Results indicate that the water structure in brain tissues may become altered at an early stage of edemic formation without causing any significant changes in cellular hydration. TIS might serve as a sensitive parameter for studying the water structure in a variety of tissues, such as in edematous brain tissue.

Animals↗
PubMed1992

Proton NMR studies on ischemic rat brain tissue.

The spin-lattice relaxation time (T1) of water protons and the cross-relaxation time (TIS) between irradiated protein protons and observed water protons were measured in order to study water-macromolecular interactions in ischemic rat brain tissues. Tissues were obtained by bilateral common carotid artery occlusion from stroke-prone spontaneously hypertensive rats. Water, Na, and K contents were measured in ischemic brain tissue at the same time. Water and Na content increased while the TIS value and K content decreased following ischemic insults. The T1 value did not change until 180 min after ischemia had been induced. Changes in the TIS value occurred earlier than changes observed for the T1 value, water, and electrolyte contents. Results indicate that the value of TIS may be useful for detecting cerebral ischemia and that the physical structure of water-macromolecular interaction may be altered soon after ischemic onset in brain tissue.

Animals↗
PubMed1992

Increased oxidized form of human serum albumin in patients with diabetes mellitus.

High-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on Asahipak GS-520H columns at neutral pH (6.87) showed a clear resolution of human mercaptalbumin (HMA) and nonmercaptalbumin (HNA), which are reduced and oxidized form of HSA, respectively. We studied the conversion of HMA to HNA (mercapt-nonmercapt conversion) as an index of oxidative change of the tissues and organs in 28 normal subjects and in a total of 47 patients with non-insulin dependent diabetes mellitus (NIDDM). Mean (+/- SD) values of the HMA fraction of HSA, f(HMA), [HMA/(HMA + HNA)], was significantly lower in NIDDM patients than in normal subjects (0.63 +/- 0.067 vs 0.75 +/- 0.028, P < 0.001). It was lower in poorly controlled NIDDM patients (0.63 +/- 0.058, n = 20) than in well controlled NIDDM patients (0.67 +/- 0.032, n = 9) (P < 0.05). Plasma glucose values sampled on occasions including overnight fasting and postprandial ones (r = -0.441, n = 47, P < 0.01), but not plasma glucose values sampled on overnight fasting (r = -0.345, n = 29) or postprandial (r = -0.467, n = 18) conditions and HbA1c (r = -0.211, n = 34), negatively correlated with the f(HMA) values, indicating that mercapt-nonmercapt conversion may not be due to cumulative hyperglycemia over a month, but due to short-term alteration in blood glucose level. The presence or absence of diabetic complications including nephropathy, retinopathy and neuropathy did not affect the f(HMA) values. In conclusion, decreased f(HMA) values in the diabetic patients suggested the presence of a rapidly altered oxidative change of albumin due to hyperglycemia.

Adult↗
PubMed1992

Quantitative and qualitative changes of serum albumin in CAPD patients.

This study was conducted to assess quantitative and qualitative changes in serum albumin in CAPD patients. For twenty-six CAPD patients as well as age-, sex- and dialysis history-matched HD patients, biochemical and physiological parameters including urea kinetics were determined. Albumin was qualitatively evaluated by HPLC. The CAPD patients showed significant decreases in serum albumin and the reduced form of albumin accompanied by a lower protein catabolic rate(PCR) compared to the HD patients. Thirty five % of CAPD patients showed mild to moderate hypoalbuminemia, associated with a higher incidence of peritonitis and longer hospital stay. Patients with hypoalbuminemia had less of the reduced form of albumin. A weak positive correlation was found between serum albumin concentration and KT/V, and PCR. Thus, in CAPD patients, there occur quantitative and qualitative changes in serum albumin. Hypoalbuminemia may be a risk factor for peritonitis and is due in part to insufficient dialysis and protein intake. Intermolecular change in albumin may possibly be due to uremia per se.

Adult↗
PubMed1991

Locations of the three primary binding sites for long-chain fatty acids on bovine serum albumin.

Binding of 13C-enriched oleic acid to bovine serum albumin and to three large proteolytic fragments of albumin--two complementary fragments corresponding to the two halves of albumin and one fragment corresponding to the carboxyl-terminal domain--yielded unique patterns of NMR resonances (chemical shifts and relative intensities) that were used to identify the locations of binding of the first 5 mol of oleic acid to the multidomain albumin molecule. The first 3 mol of oleic acid added to intact albumin generated three distinct NMR resonances as a result of simultaneous binding of oleic acid to three heterogeneous sites (primary sites). Two of these resonances were seen upon addition of 1 or 2 mol of oleic acid to fragments representing either the carboxyl-terminal half (residues 307-582) or the carboxyl-terminal domain (residues 377-582); the third resonance was seen upon addition of 1 mol of oleic acid to the fragment representing the amino-terminal half (residues 1-306). The resonance patterns for the fourth and fifth moles of oleic acid added to albumin (secondary sites) could not be duplicated by addition of more oleic acid to individual fragments. These resonance patterns were generated, however, when the two complementary fragments were mixed in equimolar proportions to form an albumin-like complex with a reconstituted middle domain. Thus, two primary fatty acid binding sites are assigned to the carboxyl-terminal domain, one primary site is assigned to the amino-terminal half, and the secondary sites are assigned to the middle domain. This distribution suggests albumin to be a less symmetrical binding molecule than theoretical models predict. This work also demonstrates the power of NMR for the study of microenvironments of individual fatty acid binding sites in specific domains.

Binding Sites↗
PubMed1991

Circular dichroic and 1H-NMR studies on the aged form of bovine plasma albumin.

Bovine plasma albumin (BPA) has 17 disulfide bonds and approximately one SH group at Cys-34 which catalyzes the intramolecular SH, S-S exchange reaction in the alkaline region at low ionic strength, resulting in the formation of the aged form (A-form). 1) Fractions of alpha-helix (f alpha) and beta-form (f beta) of iodoacetamide-blocked non-aged BPA (IA-BPA) at pH 6.5 (the N-form) and 9.0 (the B-form) in the absence of added salt were 0.70, 0.12 and 0.62, 0.18, respectively (Era et al. (1990]. However, there were no changes in f alpha and f beta of the iodoacetamide-blocked A-form (IA-A-form) over the pH range from 5.5 to 9.1 in the absence of added salt or in 0.10 M KCl (f alpha approximately 0.60, f beta approximately 0.20), indicating that the secondary structure of the IA-A-form might be similar to that of non-aged IA-BPA at pH 9.0 (B-form) in the absence of added salt, that is, the frozen B-form, stabilized covalently by the repairing of disulfide bonds. 2) The rigidity of the A- and IA-A-forms, as monitored by cross-relaxation times between irradiated and observed protein protons, was similar to or slightly higher than that of non-aged IA-BPA or BMA.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

1H-NMR studies on water structures in the rat brain tissues with cerebral tumour or ischaemia.

Spin-lattice relaxation times (T1) of water protons and cross-relaxation times (T(IS)) between irradiated protein protons and observed water protons were measured to study water structure in various rat brain tissue. A tumour-bearing rat model and an incomplete forebrain ischaemia model of stroke prone spontaneously hypertensive rats (SHRSP) were used for the experiments. T(IS) and T1 were measured by the inversion recovery FT method with and without f2-irradiation at 7.13 p.p.m. and gamma H2/2 pi approximately 69 Hz, respectively, using a 360 MHz FT-NMR spectrometer. All of experiments on T1 and T(IS) yielded a single kind of component. In spite of small changes in T1 and water content, T(IS) values in peritumoural oedematous and ischaemic brain tissue were significantly shorter than those of normal brain and far shorter than those of brain tumour, indicating a large amount of hydration of marco-molecules in the oedematous and/or ischaemic rat brain tissue. T(IS) might be sensitive parameter for studying the water structure in various brain tissue.

Animals↗
PubMed1990

Structural transition of bovine plasma albumin in the alkaline region--the N-B transition.

Bovine plasma albumin (BPA) has approximately one SH group (Cys-34) which catalyzes the intramolecular SH, S-S exchange reaction in the alkaline region at low ionic strength, resulting in the formation of the aged form. So, the N-B transition at ionic strength above 0.20 and below 0.10 was studied using BPA and iodoacetamide-blocked BPA (IA-BPA), respectively. (1) pH profiles of [theta]262 and [theta]268 of BPA in 0.20 M KCl showed the characteristic changes in the pH region 7.0-9.0, corresponding to the N-B transition. On going from pH 7.0 to 9.0 in 0.10 M KCl or NaCl, IA-BPA did not show significant changes in rotational relaxation times of tryptophyl fluorophors, CD-resolved secondary structures, spin-echo 1H-n.m.r. spectra and cross-relaxation times (TIS) between irradiated and observed protein protons, which might reflect the rigidity of the domains and/or subdomains. On the other hand, rotational relaxation times of 1-anilino-8-naphthalenesulfonate-IA-BPA complex (IA-BPA-ANS0.9, molar ratio of ANS to IA-BPA = 0.9/1) showed significant decreases from 131 to 114 ns on going from the N- to the B-forms in 0.10 M KCl. The above results and reported experimental evidence might indicate that on going from the N- to the B-forms in 0.10 M KCl or NaCl, the mutual movement of subdomains, connected with a flexible hinge region (Brown & Shockley (1982)) might increase without loss in the helicity and the rigidity of subdomains. (2) The N-B transition of IA-BPA in the absence of salt was quite different from those in 0.10 M KCl or NaCl. Decreases in the helicity and the intramolecular rigidity, as monitored by TIS-measurements, were observed on going from the N- to the B-forms.

Animals↗
PubMed1990

[Mesenteric hematoma; a pediatric case].

A 3-Year-old girl was admitted to National Beppu Hospital due to abdominal mass. US examination revealed cystic mass with multiple scattered nonreverberatory echoes in right upper abdomen. CT examination revealed almost homogeneous mass (29-31 H.U.) with a few internal components (36-42 H.U.). US and CT were useful methods for diagnosis of mesenteric hematoma.

Child, Preschool↗
PubMed1988

Histologic types of lung cancers among male Japanese copper smelter workers.

This study was done to investigate which histologic type of lung cancer is prevalent among male Japanese copper smelter workers. A panel of eight pathologists was asked to diagnose uniformly prepared materials for 19 occupational series, 87 nonoccupational bronchogenic carcinomas, and 14 benign lesions. The consensus diagnosis was used as reference. The reference diagnoses and the originals without materials employed for verification were designated as finals. Squamous cell carcinoma was the most frequent cell type in the occupational group, which comprised 21 (75.0%) of 28 histologically proven cases. There were three (10.7%) small cell carcinomas, one (3.6%) large cell carcinoma, and three (10.7%) adenocarcinomas. The proportion of Kreyberg group I in the occupational cases was significantly larger than that of lung cancers in the population-based cancer registries in Japan. These findings are compatible with Kreyberg's hypothesis. Above all, squamous and small cell carcinomas were prominent and appeared to be environmentally related bronchogenic carcinomas.

Adenocarcinoma↗
PubMed1988

Further studies on the resolution of human mercapt- and nonmercaptalbumin and on human serum albumin in the elderly by high-performance liquid chromatography.

High-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on Asahipak GS-520 showed at least two peaks, the principal component corresponding to human mercaptalbumin (HMA) and the secondary one to nonmercaptalbumin (HNA). HPLC analysis of HSA on Asahipak ES-520 N showed three peaks, the principal component corresponding to HMA, the secondary one to HNA having mixed disulfide with cysteine or glutathione and the tertiary one to HNA oxidized higher than mixed disulfide. Two kinds of rapid HPLC for the resolution of HSA into HMA and HNA were developed by the present authors. Using these HPLC, the present authors found a significant decrease in the fraction of HMA in the elderly.

Aged↗
PubMed1987

Inter- and intra-pathologist variability in histologic diagnoses of lung cancer.

To estimate variability and reliability in histologic diagnosis (Dx) of lung cancers, lung cancer preparations were divided into eight equal sets and diagnosed independently by an eight-man pathology panel. Majority Dx (Dx affirmed by more than 4 panelists) was regarded as the consensus Dx of each cancer. The consensus rate of each panelist ranged from 78.8% to 96.1% with an average of 89.4%. The consensus rates were not significantly different among the panelists. Relatively high inter-pathologist agreement was observed in squamous cell carcinoma, adenocarcinoma, and small cell carcinoma. However, regarding large cell carcinoma, there was occasional disagreement among the panelists. Forty-seven cancers were reexamined by the same panelists, with no preliminary announcement, 7 months after the first examination to study the intra-pathologist agreement. The rate of the intra-pathologist agreement ranged from 76.6% to 93.3%. Dx of large cell carcinoma was the most intra-changeable. It was concluded that the histologic Dx of large cell carcinoma was the most inter- and intra-changeable, and the most frequent dissenting Dx from it was poorly differentiated squamous cell carcinoma.

Adenocarcinoma↗
PubMed1987

The charge effects of the self-diffusion constant of bovine mercaptalbumin.

The charge effect on the translational self-diffusion constant, D, of polyelectrolytes has been quantitatively analyzed based on dynamic light scattering experiments. Perfectly monodisperse bovine mercaptalbumin has been used at low pH as a positively charged polyelectrolyte sample. Completely linear plots of log(g2(t)-1) vs. time t have been obtained for uncharged states of the protein, for the correlation function of the scattered light intensity, g2(t). The plots deviate from linearity as polyions bear the charges. The D values for various ionic states, obtained from the initial slopes of the plots, have been analyzed using the simple theory of Imai and Mandel (N. Imai and M. Mandel, Macromolecules 15 (1982) 1562) derived based on the Onsager-Navier-Stokes equation for solvent flow with counterion distribution around a polyion. It has turned out that the experimental D values coincide well with the theory and that the characteristic nature of D can be elucidated principally from the charge effect.

Diffusion↗
PubMed1986

[Diagnostic variations among eight pathologists in the histologic classification of lung cancer].

In order to estimate the magnitude of variations among pathologists in histological diagnoses of lung cancer, eight doctors were asked to independently diagnose 73 preparations of the lung (16 biopsied cancers, 27 resected specimens, 21 autopsied specimens and nine benign autopsied cases). The rates of correct diagnoses by the pathologists ranged from 81.7% to 100%, averaging 91.8%. There was no significant difference between the lowest rate and mean or median of the rates. The variation of the diagnosis tended to be more prominent in large cell carcinoma than in adenocarcinoma or small cell and squamous cell carcinoma. It was suggested that the diagnostic criteria for large cell carcinoma varied to some extent among pathologists.

Adenocarcinoma↗
PubMed1986

Water structure in modified bovine plasma albumin (BPA) gel and bovine mercaptalbumin solution. 1H-n.m.r. studies.

Bovine plasma albumin Fr. V (BPA) has been known to contain small amounts of proteolytic enzyme. Wilson & Foster (1971) found a very limited and specific cleavage of BPA catalyzed by the enzyme with BPA in the F-form near pH 3.8, resulting in the formation of partially hydrolyzed BPA (BPA*). BPA* had a tendency to form a transparent gel at pD 4.0 (pD range of the F-form) above 8%, though proteolytic enzyme-free bovine mercaptalbumin (BMA) was in a transparent solution at pD 4.0 even at 12%. Water structures of the F-form of BMA in the solution state and of BPA* in the gel state were studied by measuring 1H-n.m.r. spectra, spin-lattice relaxation time (T1) and cross relaxation time (TIS) between irradiated and observed protons. Protein concentration-dependent changes of T1 of water protons indicated that the amount of hydrated water of BPA* in the gel state is far greater than that of the F-form of BMA in the solution state. TIS values from protein protons to water protons also indicated a large amount of hydration of BPA*, strong interaction between water and BPA* and rapid exchange between bound and bulk water in the gel state.

Animals↗
PubMed1985

High-performance liquid chromatographic studies on non-mercapt in equilibrium with mercapt conversion of human serum albumin. II.

High-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on a GS-520 column with 0.03 M sodium phosphate buffer-0.15 M sodium sulphate (pH 6.87) showed three peaks, the principal component corresponding to human mercaptalbumin (HMA) and the secondary and tertiary components to nonmercaptalbumin (HNA). Using HPLC analysis, the nonmercapt----mercapt conversion of HSA during haemodialysis and the mercapt----nonmercapt conversion after haemodialysis in chronic renal failure were re-confirmed, indicating that HMA is a covalent carrier protein for sulphur-containing amino acids. Fractions of HMA in various liver diseases were significantly lower than those of healthy male adults.

Adult↗