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Biomedical subjects

J Murakami

Publications and source records attributed to J Murakami.

At least 109 records · Page 6Linked to original sources
PubMed1991

[Evaluation of pulmonary emphysema with high resolution computed tomography and the effect of smoking].

Cigarette smoking is thought to play an important part in the development of pulmonary emphysema. The authors previously reported on the correlation of high resolution computed tomography (CT) with the pathology grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. High resolution CT was effective to identify the presence and grade of mild emphysema. The mean per cent predicted FEV1 was 97 per cent. There were 28 smokers and 14 nonsmokers. In this report, the correlation of smoking history with pathology score and high resolution CT was analyzed. There was significant correlation among these indices. These results further support the relationship between smoking and pulmonary emphysema. High resolution CT scan may help in the understanding of the role of cigarette smoking in the development of early pulmonary emphysema.

Adult↗
PubMed1990

The diagnosis of mild emphysema. Correlation of computed tomography and pathology scores.

Early and accurate diagnosis of emphysema is said to be invaluable for identification of clinically silent and mild emphysema. Recently, computed tomography (CT) has been much advocated for its efficacy in detailed diagnosis of emphysema, and the results have been compared with the pathology grade of emphysema in resected lung specimens. To assess the ability of high resolution CT scan in detecting and grading mild emphysema, we correlated the high resolution CT scan with the pathology grade of emphysema and the destructive index (DI) of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. The high resolution CT scan and the cut surface of the lung, corresponding exactly to the same plane of the CT scan image, were assessed using the picture-grading system of Thurlbeck and coworkers on a scale of zero to 100. The CT scores for all patients ranged from 12 to 57, with a mean +/- SD of 22.1 +/- 9.6 using 1-mm collimation (n = 35), and from 7 to 46 with a mean +/- SD of 16.5 +/- 8.3 using 5-mm collimation (n = 33). The pathology scores ranged from 10 to 57, with a mean +/- SD of 23.2 +/- 9.8 (n = 42). The DI ranged from 15.4 to 67.1, with a mean +/- SD of 31.4 +/- 10.8 (n = 42). The CT scores using 1-mm and 5-mm collimation correlated significantly with the pathology scores (r = 0.68 and 0.76, respectively, p less than 0.001), and with the DI (r = 0.62 and 0.74, respectively, p less than 0.001). The pathology scores correlated significantly with the DI (r = 0.72, p less than 0.001). We therefore concluded that high resolution CT can help to identify the presence and grading of mild emphysema.

Adult↗
PubMed1990

Effect of cholestyramine in early weaning on later response to serum and fecal steroid levels and cholesterol 7 alpha-hydroxylase activity to high-cholesterol diet in ExHC rats.

Male ExHC (exogenous hypercholesterolemic) rats were either prematurely weaned at 17 days of age or allowed to nurse until 35 days of age. The prematurely weaned rats were either fed a diet containing cholestyramine or cholestyramine-free diet until 35 days of age. Cholestyramine supplementation markedly increased fecal bile acid excretion and modified the composition. After giving a stock diet for 7 weeks, all rats received a cholesterol-enriched diet for 9 weeks. The serum cholesterol level in later time was not affected by early dietary manipulation. The activity of hepatic cholesterol 7 alpha-hydroxylase and fecal bile acid excretion at the end of the cholesterol challenge decreased in the cholestyramine-pretreated group, when compared to the normally weaned group. Fecal excretion and the ratio of the secondary (deoxycholic and lithocholic acids) to the primary (cholic and chenodeoxycholic acids) bile acids significantly decreased in the early cholestyramine-treated group. These results suggest that a modification of bile acid metabolism in early life may strongly influence the hepatic and possibly colonic bile acid metabolism in later life, when challenged with a high-cholesterol diet.

Animals↗
PubMed1990

Immunohistochemical study of chondroitin sulfate and dermatan sulfate proteoglycan in dental pulp and dentin.

We investigated the localization of chondroitin sulfate and dermatan sulfate proteoglycans in the dental pulp and dentin of rats, using a combination of an immunohistochemical technique coupled with specific enzymatic digestion. Chondroitin 4-sulfate and dermatan sulfate were found to be widespread in pulpal connective tissue, predentin and dentinal tubules. The response to predentin was found to be particularly strong. Chondroitin 6-sulfate was stretched in pulpal connective tissue and predentin, but showed only a weak response.

Animals↗
PubMed1990

[Membranous and respiratory bronchiole disease in patients with normal air-flow and mild air-flow limitation].

In order to evaluate the role of membranous (MB) and respiratory bronchioles (RB) in patients with normal and mild airflow limitation, we quantitatively assessed the pathological change of MB, RB and alveoli in the pathological specimens of 42 patients who required surgery for removal of a solitary pulmonary nodule. We also measured the destructive index (DI), to evaluate the destruction of alveolar walls. High resolution CT scan and pulmonary function tests were performed within 1 month of resection. Results of the pulmonary function tests correlated with pathological changes of RB better than with MB. Significant correlation between the emphysema score of resected lung and the pathological change of MB and RB was observed. There was also significant correlations between the CT score or DI and RB changes. However, there was no significant correlation between the CT score or DI and the change of MB. There were significant differences between smokers and nonsmokers in the results of pulmonary function test, pathological changes of RB and severity of emphysema. We postulate that RB is responsible for subtle functional abnormalities in the early stages of chronic obstructive pulmonary disease.

Adult↗
PubMed1989

[Comparison of intravenous drip infusion excretory urography using ionic and non-ionic contrast media].

Ionic and non-ionic contrast media were compared for use in intravenous drip infusion excretory urography. Sixty consecutive cases were classified alternately into two groups, ionic and non-ionic, excluding cases which were known to have factors affecting contrast ability adversely, such as hydronephrosis, renal failure and so on. Each group consisted of 30 cases. A hundred ml of the ionic contrast medium (Diatrizoate--60% Urografin) or non-ionic contrast medium (Iopamidol--Iopamiron 300) was administered I.V. by drip infusion, each infusion taking less than 10 minutes, using a 18 G needle, and 0-minute, 10-minute and 20-minute films were obtained. Visibility of nephrogram, calyceal system, renal pelvis, ureters and bladder were evaluated, ranging from 0 to 3, by six radiologists who were not informed of the contrast medium used. Some detailed factors such as radiographic contrast and fullness of the collecting system and of the bladder were also analyzed. Visualization rate of the ureters was defined as the length of visualized ureters divided by the distance between the renal pelvis and the ureteral orifice of the bladder. There was no significant difference in visualization of nephrogram between the two groups. However, the non-ionic group was superior to the ionic group in visualization of the calyceal system and ureters with statistical significance, probably due to higher radiographic contrast of non-ionic medium. There was no statistical significance between the two groups, in fullness of the calyceal system and visualization rate of the ureters, whereas the ionic group was superior to the non-ionic group in fullness of the bladder.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Plasmacytoma of the pancreatic head.

Plasmacytomas of the pancreas are extremely rare. This is a report of a patient with plasmacytoma of the head of the pancreas who also had an extramedullary plasmacytoma of the epipharynx 19 months earlier. Computed tomographic (CT) scans revealed a multilobular homogeneous mass in the pancreas. Endoscopic biopsy of adjacent polypoid lesions in the duodenum allowed confirmation of the diagnosis.

Aged↗
PubMed1989

Near UV-induced free radicals in ocular lens, studied by ESR and spin trapping.

An electron spin resonance (ESR) study on UV-photolysis of human and canine lens nuclei was carried out at room temperature. (1) At least two kinds of free radical signals, a narrow signal and a broad one, were detected at around g = 2.004. The latter is similar to that observed upon irradiation of a model solution containing both tryptophan and cysteine. (2) Two spin adducts were detected upon irradiation of canine lens in the presence of a spin trapping reagent (DMPO, 5,5-dimethyl-1-pyrroline N-oxide), i.e. a spin adduct of sulphur-centered radical (most likely glutathione thiyl radical) and the protonated adduct of solvated electron (presumably due to photo-ionization of tryptophan). (3) A tentative and simplified reaction mechanism of UV-induced damage is discussed on the basis of these observations.

Animals↗
PubMed1989

The cerebellum in sagittal plane--anatomic-MR correlation: 1. The vermis.

Correlation of thin (5-mm) sagittal high-field (1.5-T) MR images of three brain specimens and 11 normal volunteers with microtome sections of the human cerebellar vermis and hemispheres demonstrates that proton-density-weighted (long TR/short TE) and T2-weighted (long TR/long TE) spin-echo pulse sequences provide the greatest contrast between gray and white matter. These images also can display (1) the corpus medullare and primary white-matter branches to the vermian lobules, including the lingula, centralis, culmen, declive, folium, tuber, pyramis, uvula, and nodulus; and (2) several finer secondary branches to individual folia within the lobules. Surface features of the vermis including the deeper fissures (e.g., preculminate, primary, horizontal, and prepyramidal) and shallower sulci are best delineated by T1-weighted (short TR/short TE) and T2-weighted images, which provide greatest contrast between CSF and parenchyma. Given that the width of the normal vermis varied from 6 to 12 mm in our volunteers, the acquisition of thin slices (less than or equal to 5 mm) was required to minimize volume averaging of the cerebellar hemispheres with the vermis on a midline sagittal MR section. Knowledge of the detailed normal anatomy of the cerebellar vermis on sagittal MR images can assist in the identification of various pathologic alterations.

Adolescent↗
PubMed1989

The cerebellum in sagittal plane--anatomic-MR correlation: 2. The cerebellar hemispheres.

Thin (5-mm) sagittal high-field (1.5-T) MR images of the cerebellar hemispheres display (1) the superior, middle, and inferior cerebellar peduncles; (2) the primary white-matter branches to the hemispheric lobules including the central, anterior, and posterior quadrangular, superior and inferior semilunar, gracile, biventer, tonsil, and flocculus; and (3) several finer secondary white-matter branches to individual folia within the lobules. Surface features of the hemispheres including the deeper fissures (e.g., horizontal, posterolateral, inferior posterior, and inferior anterior) and shallower sulci are best delineated on T1-weighted (short TR/short TE) and T2-weighted (long TR/long TE) sequences, which provide greatest contrast between CSF and parenchyma. Correlations of MR studies of three brain specimens and 11 normal volunteers with microtone sections of the anatomic specimens provides criteria for identifying confidently these structures on routine clinical MR. MR should be useful in identifying, localizing, and quantifying cerebellar disease in patients with clinical deficits.

Cerebellum↗
PubMed1989

[Role of heparitinase in the initial stage of gingival inflammation].

For the purpose of elucidating the effect of heparitinase in gingival tissue, paper strips were inserted in the gingival sulcus of a dog and were treated with heparitinase (experimental group), an enzyme-free solution (control group) or inactivated enzyme (control group) for 20 minutes once a day in order to determine the pathohistological changes in the periodontium after 3, 10 and 14 days. No marked difference was noted between the 3-day enzyme-treated group and the control groups, but for the 10-day and 14-day enzyme-treated groups, enlargement of the intercellular epithelium, neutrophil infiltration and inflammatory cellular infiltration, mainly of neutrophils, in the subepithelial connective tissue were observed. Examination of the effect of a tracer, 3H-Dextran, on the permeability of the epithelium to heparitinase revealed incorporation of 3H-Dextran by the enzyme-treated group at about 2 times as much as that by the control group, and there were more silver particles indicative of 3H-Dextran according to autoradiographic findings. Determination of the intratissue location of bacterium-derived heparitinase by the fluorescent antibody technique revealed fluorescence positivity on the gingival sulcus epithelial side but not on the oral epithelial side, and that it was more frequent in the region of the enlarged intercellular area of the upper layer of the gingival sulcus epithelium. These results suggest that bacterium-derived heparitinase present in the epithelium of the gingival sulcus of a dog lowered the defense competence peculiar to the epithelium and elevated of the permeability epithelium to bacterium-produced substances, leading to its involvement in the onset of gingival inflammation by decomposing heparan sulfate, an inter-cellular epithelial matrix.

Animals↗
PubMed1989

Transient control of serum cholesterol homeostasis in adult ExHC (exogenous hypercholesterolemic) rats by dietary cholesterol during weanling period.

Rats hyper-responsive to a diet containing cholesterol plus cholic acid (exogenous hypercholesterolemic (ExHC) rats) were used to assess if cholesterol feeding at weanling period influences later serum cholesterol homeostasis. Diets containing cholesterol plus cholic acid (atherogenic diet) in early life, when compared to non-atherogenic diet, caused a transient suppression of serum cholesterol elevation in very-low- and low-density lipoprotein fractions during refeeding of the atherogenic diet in later life. Such an effect was not observed when ExHC rats were early given a diet supplemented with cholesterol or cholic acid alone, nor when ordinary Sprague-Dawley rats were given atherogenic diet. Early atherogenic diet caused an increased secretion of cholesterol as very-low-density lipoprotein from the perfused livers of adult ExHC rats. Neither the activity of hepatic cholesterol-7 alpha-hydroxylase of fecal steroid excretion in later life was influenced by the early dietary manipulation. Therefore, the present results show the deferred effect of early dietary manipulation on later serum cholesterol metabolism in ExHC rats, but the underlying mechanism(s) remains to be determined.

Animals↗
PubMed1989

[Clinical evaluation of synthetic hydroxyapatite implants for human periodontal osseous defects. 6 cases studied more than 3 years after the surgery].

We applied of granular hydroxyapatite HAP to periodontal bone defects, for the purpose of restoring the periodontal tissue destroyed by periodontal disease, the subjects were 6 patients (6 regions) with chronic marginal periodontitis who had passed more than 3 years since HAP implantation. After routine periodontal initial treatment, a flap operation was performed, and granular HAP, or a combination of granular and block-like HAP, was implanted into the periodontal bone defect. Clinical parameters were probing depth, clinical attachment level, clinical gingival margin, residual HAP volume and X-ray before operation, at 3, 6, 12 months, and 2, 3, and 4, 6 years after the operation. The results revealed that all measured values showed good results for both granular HAP and the combination of granular and block-like HAP after implantation, and that all cases showed stable results from 12 months on. No remarkable difference was noted between the implanted regions.

Bone Resorption↗
PubMed1989

[Comparison of high resolution computed tomography and pulmonary function tests in diagnosis of mild emphysema].

To assess the ability of high resolution CT scan and pulmonary function tests in detecting and grading mild emphysema, we correlated the high resolution CT scan and pulmonary function tests with the pathologic grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for solitary pulmonary nodules. Using the high resolution CT scan, we could identify the pathologic grade of mild and moderate emphysema. By measuring diffusing capacity per unit alveolar gas volume (DLco/VA), it seemed to be possible to detect the mildest degree of alveolar destruction assessed by the destructive index, which was not detected by high resolution CT scan. The reason for these results seemed to be that we assessed the severity of emphysema by detecting the air space enlargement on high resolution CT scan images caused by the destruction of alveolar walls, which were detectable by measuring DLco/VA. We conclude that it is possible to detect mild emphysema using the combination of high resolution CT scan and pulmonary function tests.

Adult↗
PubMed1988

Oscillatory deformation of human erythrocytes in sinusoidally modulated shear flow.

The red cell deformation under oscillatory shear stress was studied. Shear stress was sinusoidally modulated between 8 and 32 dyn/cm2, thus, the extent of cellular deformation altered sinusoidally. At a low modulation frequency (less than 1.8 Hz), intact red cells perfectly responded to the shear stress applied on cells, and they could deform as much as the deformation in stationary shear flow. Above 2 Hz, the cellular deformation could not follow changes in shear stress along up-phase in the shear stress cycle. As decreasing the intracellular hemoglobin concentration, the cellular response to oscillatory shear stress became better. Treatment of cells with low concentrations of diamide impaired the response of intact cells to oscillatory shear stress, but unaffected the response of partially hemolyzed cells. These data suggest that the cellular response to oscillatory shear stress is determined by the cytoskeletal structure and the intracellular viscosity.

Blood Viscosity↗