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H Nishimura

Publications and source records attributed to H Nishimura.

At least 1,045 records · Page 58Linked to original sources
PubMedDate not supplied

MRI of ganglioneuroma: histologic correlation study.

PURPOSE: The purpose of this study was to evaluate the MR findings of ganglioneuroma and to correlate imaging and histologic features. METHOD: Conventional SE and contrast-enhanced dynamic MRI was used to examine 10 patients with pathologically confirmed ganglioneuroma. The morphologic features, signal intensity, and dynamic enhancement pattern of the tumors were retrospectively analyzed and correlated with histologic features. RESULTS: Capsules were present in all tumors histologically and were also detected in five tumors on postcontrast T1-weighted images. A whorled appearance corresponding to interlacing bundles of Schwann cells and collagen fibers on histologic specimens was visualized in five tumors on T1-and/or T2-weighted images. Tumors with markedly high signal intensity on T2-weighted images consisted histologically of a large amount of myxoid stroma and relatively few cellular and fibrous components. Tumors with intermediate to high signal intensity consisted of numerous cellular and fibrous components and little myxoid stroma. Early enhancement of tumors was usually lacking in dynamic MR studies; however enhancement gradually increased. CONCLUSION: The results suggest that the MR features of ganglioneuroma are well correlated with histologic findings.

Adolescent↗
PubMedDate not supplied

Effects of converting-enzyme inhibition on cardiorenal hemodynamics in patients with chronic congestive heart failure.

The role of the renin-angiotensin system in cardiorenal function in patients with severe chronic congestive heart failure was investigated. A single oral dose of captopril in 16 patients significantly increased cardiac index and reduced arterial blood pressure and total systemic vascular resistance. These changes were significantly greater in subjects with higher baseline plasma renin activity (PRA). During 7-day captopril therapy, renal plasma flow distinctly increased in 10 patients in whom renal function was followed. The increase found in renal plasma flow was greater in subjects with higher PRA. Yet, the reduction in renal vascular resistance was much greater than that of total systemic vascular resistance, even in patients with lower PRA. Simultaneous infusion of aprotinin in eight of these subjects did not affect the captopril-induced increase in renal plasma flow, despite the suppression of plasma bradykinin levels; these responses were the same in both PRA subgroups. The results suggest that captopril reduces total systemic vascular resistance in patients with chronic congestive heart failure through inhibition of the renin-angiotensin system and that the preferential renal vasodilator effect of captopril might be the sole result of this inhibition, with the kallikrein-kinin system or kinin-mediated prostaglandins not playing a major role.

Adult↗
PubMedDate not supplied

A case of retroperitoneal malignant mesenchymoma.

A rare case is reported of malignant mesenchymoma of a retroperitoneal lesion involving the kidney and composed of leiomyosarcoma and liposarcoma. The tumor, measuring 13 x 12 x 11 cm and weighing 1910 g, arising from the soft tissue of the retroperitoneum or renal capsule, was completely removed surgically. Thirteen months after surgical operation, multiple metastasis was observed. Immunohistochemical and electron microscopical examination showed two different mesenchymal elements. Magnetic resonance imaging findings were compatible with the pathological findings. This case appears to be the second in the world literature.

Aged↗
PubMedDate not supplied

MR imaging of soft-tissue masses of the extraperitoneal spaces.

Magnetic resonance (MR) imaging has an increasing role in evaluating soft-tissue masses of the extraperitoneal spaces. Since the MR imaging features of most soft-tissue masses are nonspecific, prediction of a specific histologic diagnosis remains a challenge for the radiologist. However, there are certain specific MR imaging appearances that are helpful for more accurate diagnosis. Some histologic components, such as myxoid stroma, collagen fibers, calcification, and fat, have characteristic MR imaging features. Recognition of these features can assist the radiologist in limiting the differential diagnosis. Dynamic enhancement patterns can reflect the vascularity of masses and may be useful in diagnosis, especially in differentiating benign from malignant soft-tissue masses. Familiarity with specific signs and knowledge of diagnostic pitfalls are also important for shortening the list of differential diagnoses. Specific signs are the target sign, the bowl of fruit sign, a whorled appearance, a flow void, speckled enhancement, associated lymphadenopathy, and extension into the intervertebral foramen. Diagnostic pitfalls are as follows: a myxoid stroma simulating cystic degeneration and necrosis, collagen fibers simulating hemorrhage, a fat component simulating extraperitoneal fat, extensive intratumoral hemorrhage simulating hematoma, benign masses mimicking malignant ones, malignant masses mimicking benign ones, and peritoneal lesions mimicking extraperitoneal masses.

Contrast Media↗
PubMedDate not supplied

The distribution fields of sensory neurons in the human thalamus.

Thalamic neurons were identified by activity related to passive joint movement, active joint movement, tapping stimulation, and light touch stimulation during surgery to treat movement disorders. The neurons were classified into three types: movement-related neurons, tapping-related neurons, or superficial sensory neurons. Tapping-related neurons had characteristics of lemniscal sensory neurons and occupied the border area of movement-related neurons and superficial sensory neurons. Tapping-related neurons showed a laminar distribution 1.0-1.5 mm in width in the anterodorsal region of the nucleus ventrocaudalis. Results suggest that the distribution pattern of tapping-related neurons in the human thalamus is consistent with the functional distribution pattern found in the monkey thalamus.

Brain Mapping↗
PubMedDate not supplied

Renin-angiotensin and adrenergic mechanisms in control of blood pressure in fowl.

Many avian species demonstrate atherosclerosis and high blood pressure (BP) that are influenced by age, sex, diet, and environment, but show no arteriosclerosis in small vessels. Thus, we aimed to define neural and humoral control of BP in conscious, 32-wk-old female chickens, Gallus gallus. Mean aortic pressure (determined by chronically implanted catheter) was 137.6 +/- 2.0 mm Hg; heart rate was 295 +/- 4 beats/min. Plasma renin activity (PRA), measured by radioimmunoassay of fowl angiotensin I ([Asp1, Val5, Ser9]AI), and plasma angiotensinogen levels were 3.55 +/- 0.31 ng/ml/hr and 1229 +/- 66 ng/ml respectively. Repeated injection of propranolol (4 to 8 mg/kg/day, i.m.) decreased (p less than 0.01) the BP 19.1 +/- 3.0 mm Hg and heart rate 76 +/- 6 beats/min. Acute infusion of propranolol also markedly reduced BP and heart rate, and increased plasma levels of norepinephrine and epinephrine. SQ 14,225 (20 mg/kg/day) reduced BP (p less than 0.01), but BP returned towards original levels unless a higher dose was given. PRA increased 2- to 6-fold. BP also decreased 31.0 +/- 2.1 mm Hg after reserpine treatment, but not after [Sar1, Ile8]AII. These results suggest that in maintaining BP in fowl the beta-adrenergic function is important, whereas the renin-angiotensin system may not have a primary role.

1-Sarcosine-8-Isoleucine Angiotensin II↗
PubMedDate not supplied

Synthesis of nonmammalian angiotensins and their comparative pressor properties in dogfish shark, domestic chicken, and rat.

To understand how vertebrates utilize angiotensins during evolutionary development, we undertook studies to synthesize and/or characterize angiotensin-like peptides from nonmammalian species. The present paper describes the synthesis of [Asp1,Val5,Asn9] angiotensin I (bull frog, Rana catesbeiana) (I), [Asn1,Val5,His9] angiotensin I (Japanese goosefish, Lophius litulon) (II), [Asn1, Val5,Asn9] angiotensin I (chum salmon, Oncorhynchus keta) (III), and [Asn1, Val5,Tyr9] angiotensin I (related to native angiotensin in snake, Elaphe climocophora (IV). Pressor properties of these peptides were compared with the peptides isolated from other species and related synthetic analogs in one representative species from three distinct classes of vertebrates: 1) elasmobranchs: spiny dogfish shark; 2) birds: domestic chicken; and 3) mammals: rat. The effect of angiotensins on short circuit current (to compare sodium and water permeability) was studied by adding these on the dermal side of the isolated frog skin. In the rat pressor bioassays, the above peptides possessed, respectively, I, 87.8%; II, 51.5%; III, 65.2%; and IV, 60.3% pressor activity of [Ile5] angiotensin II, which was blocked with a converting-enzyme inhibitor, captopril. In the conscious dogfish shark, the percentage increase of blood pressure based on preinjection level (= 100) in the dorsal aortic pressure was 35% to 60% for [Asp1,Ile5,His9] angiotensin I (human) (3 micrograms/kg), [Asp1,Val5,Ser9] angiotensin I (chicken) (3 micrograms/kg), [Asp1,Ile5] angiotensin II (3.6 micrograms/kg), and [Asn1,Val5] angiotensin II (6 micrograms/kg). Likewise, a 30% to 35% increase in blood pressure was obtained with angiotensin III (3 micrograms/kg), [Ile8] angiotensin II (4.4 micrograms/kg), and [Sar1,Ile8] angiotensin II (9.1 micrograms/kg). [Sar1,Thr8] angiotensin II and [Ile8] angiotensin I did not produce a significant pressor response even at high dose-level (8 micrograms/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin I↗
PubMedDate not supplied

Radioprotective and radiosensitizing effects of sulfur-containing amino acid derivatives on mice.

Both protection and sensitization of Mice C57Bl against 60Co gamma-rays by sulfur-containing amino acid derivatives--S-alkyl-L-cysteines, S-alkyl-2-methyl-DL-cysteines and their hydantoin derivatives, and sulfoxides of these compounds--were examined. DL-5 Allylthiomethyl-5-methylhydantoin (150 mg/kg body weight) had a remarkable radioprotective effect. The survival ratio was 4.3 or above two times as much as that of L-cysteine. On the other hand, its sulfoxide had a radiosensitizing effects; survival ratio, 0.333.

Amino Acids↗
PubMedDate not supplied

A case of malignant lymphoma accompanied with arterial bleeding from the gastric lesion.

We experienced a case of malignant lymphoma with gastric and ileo-caecal lesions. The case was 80 year-old Japanese female with a chief complaint of anorexia. The patient had gross hematemesis on the 4th day of admission. By emergency gastroendoscopy, multiple small gastric ulcers which have sharp marginal prominences were observed. Pulsating arterial bleeding was observed and we successfully achieved hemostasis by topical injection of pure ethanol under gastroendoscopy. Biopsy specimen of that lesion showed it was malignant lymphoma.

Aged↗
PubMedDate not supplied

Marchiafava-Bignami disease: consecutive observation at acute stage by magnetic resonance imaging and computerized tomography.

A 62-year-old male Japanese, a heavy drinker for his last 40 years, was admitted to our hospital because of unstable gait of acute onset. Despite large doses of thiamine injection, his condition rapidly worsened with confusion, and died 15 days after the onset. During the deteriorating course, a series of Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) scans were taken of the brain, which revealed progressive multifocal involvement in the corpus callosum; Marchiafava-Bignami disease was suggested. To the authors' best knowledge, there have been no MRI examinations conducted from so early a stage of this disease on. MRI scanning proves to be a highly useful tool for early diagnosis of Marchiafava-Bignami disease.

Alcoholism↗
PubMedDate not supplied

Development of the eyeball during fetal life.

Two hundred fifty-two undamaged human fetuses without external malformations were supplied by the human embryo and fetus collection of the Department of Anatomy, Kyoto University. The sagittal, vertical and horizontal diameters of the eyeball were measured by micrometer, and the transverse, vertical and horizontal circumferences of the eyeball were measured by mapmeter from photographs of the side views of the eye. All the diameters of the eyeball showed a parallel linear increase from the 12th to the 40th week of menstrual age. The increase of circumferences of the eyeball paralleled each other throughout the 12th to the 40th week. It is significant that the sagittal diameter of the eyeball is shorter than the vertical and transverse diameters during fetal life. The vertical meridian circumference of the eyeball is also shorter than the transverse and horizontal meridian circumferences during fetal life. These findings suggest that many infants are apt to have hyperopia at birth.

Eye↗
PubMedDate not supplied

Applicability and advantages of flow artifact-insensitive fluid-attenuated inversion-recovery MR sequences for imaging the posterior fossa.

We describe a new sequence, flow artifact-insensitive fluid-attenuated inversion recovery (FAIS-FLAIR), that capitalizes on the advantages of fluid-attenuated inversion recovery (FLAIR) while minimizing FLAIR-related artifacts such as those often encountered in the posterior fossa. Twenty-eight patients with posterior fossa disease underwent FAIS-FLAIR, conventional FLAIR, and spin-echo MR studies, and the findings yielded by the three techniques were compared. In this patient population, postcontrast FAIS-FLAIR imaging was obtained in 20 patients and compared with postcontrast T1-weighted images. The images were assessed for lesion conspicuity by three radiologists. FAIS-FLAIR markedly reduces the inflow artifacts from noninverted CSF on FLAIR images. It does so with and without contrast agent administration, and produces higher lesion conspicuity compared with T1- and T2-weighted spin-echo sequences and conventional FLAIR images of the posterior fossa.

Artifacts↗
PubMedDate not supplied

Antiproliferative effects of small fruit juices on several cancer cell lines.

Juices prepared from small fruits, mainly growing in the northern part of Japan, were studied in an attempt to explore the feasibility of an assay that screens cytotoxic properties. Screening of 43 small fruit juices indicated that Actinidia polygama Maxim., Rosa rugosa Thunb., Vaccinium smallii A. Gray and Sorbus sambucifolia Roem, strongly inhibited the proliferation of all cancer cell lines examined and yet these juices were substantially less cytotoxic toward normal human cell lines.

Beverages↗
PubMedDate not supplied

Ocular malformations in human fetuses with external malformations.

Sixty undamaged human fetuses with various nonocular external malformations were selected randomly from a large number of fetuses collected by the Department of Anatomy Faculty of Medicine, Kyoto University, and examined macroscopically and stereomicroscopically for ocular and other external and internal malformations. Eighteen fetuses (30 percent) showed ocular malformations of the following types: approximated eyes (two cases), approximated eyes plus microncornea (one case), microphthalmia (eight cases), microcornea (three cases), corneal opacity (one case), transparent sclera (two cases), and antimongoloid obliquity of the palpebral fissure (one case). In addition, asymmetric insertion sites of the recti muscles, regarded as a minor deviation, were found in 12 cases (20.0 percent). Of the fetuses with malformations in the central nervous system 37.5 per cent showed ocular malformations. No specific causes of ocular malformations could be confirmed in the present study. However, drugs such as hormones, sedatives and antipyretics in the early stage of pregnancy, systemic diseases such as influenza, and dysplasia or dysfunction of the ovary or uterus might be related to the production of some ocular and other malformations.

Abnormalities, Multiple↗