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Biomedical subjects

H Sano

Publications and source records attributed to H Sano.

At least 271 records · Page 15Linked to original sources
PubMed1998

Fluorescence energy transfer of complexes of skeletal muscle troponin C and melittin derivatives.

We studied Ca2+-dependent structural change of rabbit skeletal troponin C (TnC)-melittin (ME) complex as a model of TnC-troponin I complex. In previous study, we found that the distance between Met-25 and Cys-98 of TnC in TnC-ME complex increased upon binding of Ca2+ to TnC [H. Sano and T. Iio (1995) J. Biochem. 118, 996-1000]. In this study, we used a fluorescence energy transfer method. As a fluorescent donor, we used the tryptophan residue in four melittin derivatives, in which residue 2, 5, 8, or 13 was replaced with tryptophan. As acceptor, we used dansylaziridine (DANZ) bound to Met-25 of TnC, or N-iodoacetyl-N'-(5-sulfo-1-naphthyl)ethylenediamine (1,5-I-AEDANS) bound to Cys-98 of TnC. For all TnCDANZ-ME complexes, the donor-acceptor distance (11.9-17.7 A) did not remarkably depend on Mg2+ or Ca2+ binding of TnC or on the position of tryptophan in ME derivatives. The same results were obtained for TnCAEDANS-ME complexes in the absence of Ca2+ (distance 15.2-21.7 A). But in the presence of Ca2+, tryptophan residues in the central region of ME were near to Cys-98 of TnC (distance much less than 10.4 A). Based on these results, we conclude that ME is enfolded by the N- and C-lobes of TnC, and the ME rod is almost perpendicular to a line connecting Met-25 and Cys-98 of TnC. The position of the ME rod shifts upon binding of Ca2+ to TnC.

Amino Acid Sequence↗
PubMed1998

Intracellular changes in ions and organic solutes in halotolerant brevibacterium sp. Strain JCM 6894 after exposure to hyperosmotic shock

In the present study we aimed to observe the intracellular responses when there was a hyperosmotic shock with a large shift in ionic strength in nutrient-rich and nutrient-poor external environments in order to clarify the availability of substrates. To do this, we used the halotolerant organism Brevibacterium sp. strain JCM 6894, which is able to grow in the presence of a wide range of salt concentrations. Hyperosmotic shock was induced by transferring cells in the late exponential phase of growth in a complex medium containing 0.5 M NaCl into either old or fresh culture medium containing 2 M NaCl. Changes in the growth rate, in the pH of the medium, and in the internal cation or organic solute concentrations in the cytosol after an upshock were analyzed as a function of incubation time. The cells exhibited very different responses to upshocks in fresh culture medium and in old culture medium; in fresh culture medium, growth was stimulated and the medium became more acidic, whereas the old culture medium repressed growth and the medium became more alkaline. The intracellular free Na+ concentrations remained low (80 nmol mg of protein-1) after an upshock in fresh culture medium, although they quickly increased twofold in the old culture medium. In contrast, K+ ions immediately accumulated in the cells in fresh culture medium, whereas K+ ions were taken up quite slowly in old culture medium. Furthermore, the cells placed in fresh culture medium transiently accumulated alanine and glutamine in response to the upshock, but the cells placed in old culture medium did not. Growth of the Brevibacterium strain at higher levels of salinity was supported by ectoine synthesis but was not observed after the shift to high-osmolarity conditions in the old culture. In the fresh culture, however, ectoine was vigorously synthesized in cells for more than 5 h after the upshock; the concentration of ectoine in cells was more than 3,500 nmol mg of protein-1 at 10 h, which corresponded to a ninefold increase compared to the concentration before the shock. These findings are consistent with the results of an analysis of the extracellular medium composition before and after the upshock.

Journal Article↗
PubMed1998

Plasma soluble fas and soluble fas ligand in chronic glomerulonephritis.

It has been reported that glomerular cells with apoptosis and positive Fas immunoreactivity are seen in proliferative glomerulonephritis (PGN). Fas induces apoptosis when it binds to Fas ligand (Fas-L) or soluble Fas-L (sFas-L). However, soluble Fas (sFas) blocks apoptosis by inhibiting binding between Fas and Fas-L or sFas-L. That is, Fas, Fas-L, and sFas-L are inducers of apoptosis, but sFas is an inhibitor of apoptosis. We studied the relationship between the plasma levels of sFas and sFas-L in 32 patients with various types of adult chronic glomerulonephritis. Patients with serum creatinine levels >1.5 mg/dl (132.6 micromol/l) were excluded. The plasma levels of sFas-L were within the normal limits in all patients. The plasma levels of sFas in the patients with minimal-change (n = 8) and membranous nephropathy (n = 7) were similar to the age- and sex-matched controls. However, the plasma sFas levels were significantly elevated in patients with mesangial PGN (n = 10) and membranoproliferative glomerulonephritis (n = 7)(3. 4 +/- 0.9 and 3.9 +/- 1.5 ng/ml, respectively) as compared with the age- and sex-matched controls (controls: 2.1 +/- 0.4 and 2.2 +/- 0.6 ng/ml, respectively). In PGN, according to increase of histological grade and decrease of creatinine clearance, the number of TUNEL-positive cells in glomeruli is decreased in spite of an increase of the Fas positivity, and plasma sFas is increased. The degree of proliferative change is determined by the balance between proliferation and apoptosis and/or necrosis. Therefore, increased plasma sFas in PGN may inhibit apoptosis in glomeruli and may be one of the progressing factors in PGN. Thus, we conclude that an increase in plasma sFas levels is important to the protection of apoptosis in PGN.

Adult↗
PubMed1998

Structural disorders at the insertion of the supraspinatus tendon. Relation to tensile strength.

We examined macroscopically and microscopically 55 cadaver rotator-cuff tendons attached to their humeral heads to determine the distance between the edge of the articular cartilage and the tendon insertion of the supraspinatus (the width of the sulcus) and the score of regressive changes at the sulcus. In 33 specimens we measured the tensile strength. The width of the sulcus was correlated with the score of regressive changes and with the ultimate tensile strength of the supraspinatus tendon. The width of the sulcus correlated positively with the score of regressive changes (r = 0.66, p < 0.0001), but there was a negative correlation between the latter and the ultimate tensile strength (r = -0.81, p = 0.001) and between the width of the sulcus and the ultimate tensile strength (r = -0.74, p = 0.004). We believe that the width of the sulcus is a simple and useful clinical indicator of the integrity and the tensile strength of the supraspinatus tendon.

Adult↗
PubMed1998

Pathogenesis of soft-tissue contracture in club foot.

We investigated the pathogenesis of soft-tissue contracture in club foot, using immunohistochemistry to study 41 biopsy specimens and 12 normal deltoid ligaments from cadavers. Five biopsy specimens were studied by electron microscopy (EM) to determine the presence of myofibroblasts. All 41 specimens of club foot stained positively for vimentin as against only one of the 12 control specimens. By contrast, there was no difference in staining for desmin or alpha-smooth muscle actin. EM showed some variability in the appearance of ligamentous cells. Most contained bundles of microfilaments in the cytoplasm and many had abundant pinocytotic vesicles, but no basal lamina or plasmalemmal attachment plaques. Cells of the medial ligamentous tissue in patients with club foot contain vimentin and others have myofibroblastic characteristics. Both features may contribute to recurrence after soft-tissue release.

Actin Cytoskeleton↗
PubMed1998

Successful resection of arteriovenous malformations in eloquent areas diagnosed by surface anatomy scanning and motor evoked potential.

Successful resection of cerebral arteriovenous malformations (AVMs) involving the sensorimotor cortex was achieved in 17 cases. The theoretical basis for performing resection of AVMs in eloquent areas is the fact that the brain in and around the nidus about 1 mm in thickness is considered not to be functioning. It is also considered that any center of important function, when an AVM is involved, shifts to the near-by cortex from the original site. Nevertheless, it is critically important to recognize the cortex functioning as sensorimotor centers before and during operation. For this purpose, we have used surface anatomy scanning (SAS) in combination with magnetic resonance angiography. SAS is found to be very useful for the recognition of the topographical relationship between the surface anatomy and AVM. During operation, the motor cortex is identified with motor evoked potential. We have found that, in some cases, the motor center has shifted to the accessory motor cortex. With these information, it is possible to start resection of the lesion from dissection of the main feeders and dissection of the nidus from a silent cortex toward the critical area. Apparent neurological improvements were achieved in 15 of 17 patients treated surgically (88%). With this result, we think that AVMs in eloquent areas can be treated successfully when the surgery is well-designed and well-oriented with the combined use of diagnostic imaging and monitoring. As for control of intraoperative bleeding, careful attention to small but important surgical techniques avoids troublesome bleeding during AVM surgery.

Arteriovenous Malformations↗
PubMed1998

Treatment and results of partially thrombosed giant aneurysms.

Partially thrombosed giant aneurysms are one of the most difficult diseases in the neurosurgical field. We have had 18 of these cases namely, three in vertebral artery, four in basilar artery, four in internal carotid artery, five in middle cerebral artery, and two in anterior communicating artery. Nine aneurysms were clipped, two aneurysms were removed with anastomosis, two cases were treated interventionally, and five cases were treated conservatively because of serpentine and fusiform types of aneurysms in internal carotid artery bifurcation. These conservatively treated patients died due to infarction. When surgery is selected in the thrombosed giant aneurysms, the approach is the most important to secure the neck. Three-dimensional computed tomography angiography was useful to plan the strategy for surgery. If the neck is big enough for placement of a clip, arterial reconstruction is the choice. The reconstruction must be done including an adequate size of the artery because of the thick wall. If the aneurysm neck is too small to reconstruct, aneurysmectomy with anastomosis is one of the choices.

Adult↗
PubMed1998

[A case of severe neuropsychiatric lupus erythematosus treated by plasmapheresis: diagnostic values of serum antiribosomal P protein antibodies and interleukin-6 in cerebrospinal fluid].

We report here a case of neuropsychiatric lupus erythematosus with organic brain syndrome and transverse myelitis which was successfully managed by plasmapheresis. A 27-year-old female with facial rash, arthralgia and fever was diagnosed as having SLE and treated with oral prednisolone (PSL) in June 1996. After 6 weeks she demonstrated muscle pain and a spiking temperature. The dose of PSL was increased but clinical symptoms did not improve. In August, pulse methyl-PSL was performed and she subsequently-developed delirium, impairment of orientation, memory and perception, which were followed by paraplegia of the lower extremities and loss of sphincter control. Intravenous bolus cyclophosphamide was not effective, but liver dysfunction, bone marrow suppression and respiratory failure due to an infection of pneumocystis carinii were observed. We then performed plasmapheresis or immunoabsorption several times. After this treatment steady improvement was observed. High values of antiribosomal P protein antibodies in the serum and interleukin-6 in the cerebrospinal fluid decreased. Small foci of increased signal intensity detected on cranial magnetic resonance imaging and hypoperfused areas on single-photon emission CT diminished. The patient was maintained on low-dose PSL and no recurrence has been observed 15 months from the onset.

Adult↗
PubMed1998

[A case of systemic lupus erythematosus complicated with marked intestinal edema and paralytic ileus].

A 43-years-old female was admitted to our hospital because of facial erythema and photosensitivity in 1983 and was diagnosed as systemic lupus erythematosus (SLE). She was treated with betamethazone 2.5 mg/day as an outpatient. Abdominal pain and diarrhea were developed in September, 1995. So she was admitted to our hospital and diagnosed as having paralytic ileus. Ultrasonography showed marked intestinal edema. Forbidden oral intake and given antibiotics, she was satisfactorily improved in a few days, but the symptoms got worse soon. We forbid oral intake again. We performed a pulse therapy with 1 g of methylprednisolone and increased a dose of betamethasone 2.5 to 4.0 mg/day, but the symptoms were not improved. Since October 6th, serum creatinine level (s-CRE) increased to 8.1 mg/dl at October, 20th. We suspected the worsening of SLE nephropathy or drug-induced nephropathy, so we stopped a medication of pravastatin and used 50 mg/day of azathioprine. Moreover, we did a pulse therapy of methylprednisolone and a plasmapheresis. By these treatments, s-CRE level returned to normal range and paralytic ileus was completely improved. The cause of hypercreatininemia was suspected to be rhabdomyolysis due to pravastatin. The main cause of paralytic ileus with intestinal edema was suspected to be vascular disturbance of superior mesenteric arteries. We consider that pulse therapy and plasmapheresis are useful for a patient of SLE with marked intestinal edema and paralytic ileus.

Adult↗
PubMed1998

Multiple regression analysis of airway responsiveness in adult asthmatic patients.

The aim of this study was to determine which background variables exert the most influence on airway responsiveness in adult asthmatic patients. The relationships between airway response and background variables were investigated by multiple linear and logistic regression analysis in 97 asthmatic patients. Airway responsiveness was measured by the oscillation technique during methacholine inhalation challenge. The regression analyses revealed that modified Aas score "one of asthma severity score", was the major factor contributing to airway hyperreactivity. We conclude that the number of attacks during a previous year is the most important background factor related to airway hyperresponsiveness on a clinical basis.

Asthma↗
PubMed1998

[Hearing recovery in sudden deafness with profound hearing loss].

We investigated the hearing recovery in 51 patients with sudden deafness with the initial averaged five-frequency hearing levels worse than or equal to 100 dB. Twenty-two patients were treated in an outpatient setting with a peri-oral steroid, vasodilator, metabolic activator, and vitamin B. The remaining 29 patients were treated in the hospital with additional hyperbaric oxygenation therapy and/or Satellite ganglion block. The results were as follows. 1) The ultimate averaged five-frequency hearing levels were mainly distributed from 55 to 80 dB. Only seven patients showed ultimate hearing levels worse than 100 dB. Two patients achieved complete recovery better than 20 dB. 2) There was no significant difference in the hearing recovery between the patients treated in an outpatient setting and in the hospital. 3) The time interval until the hearing recovery began was distributed broadly between 2 and 28 days from the onset. While most of the patients who began to recover within 14 days from the onset showed ultimate hearing levels better than 80 dB, the patients who recovered after 14 days had worse hearing levels.

Adolescent↗
PubMed1998

Effect of operator variability on dentin adhesion: students vs. dentists.

The purpose of this study was to evaluate the operator variability of two dentin bonding systems. Fourteen undergraduate students and ten dentists of different levels of clinical experience were selected. Tensile bond strengths between resin composite and bovine dentin using dentin adhesive systems (Clearfil Liner Bond II: LB II; Scotchbond Multi-Purpose: MP) bonding systems showed a large scatter among students and dentists. The dentists group demonstrated no statistically significant differences for mean bond strengths between LB II and MP. The student group recorded a statistically greater bond strength using LB II. The mean coefficient of variation of the dentists group showed no statistically significant difference between LB II and MP, however that of the students group was lower with LB II. When using MP, the dentist group demonstrated a lower coefficient of variation than that of the student group. In order to obtain optimal bonding performance, or when beginning the use of a new system, the operator should be aware of the technique sensitivity of some adhesive systems and sensitivity to operator variability.

Analysis of Variance↗
PubMed1998

[Idiopathic insomnia].

Idiopathic insomnia (Childhood-onset insomnia) which belongs to Intrinsic Sleep Disorders in ICSD, has some dysfunction in sleep-wake center in brain. Sleep-wake center consists of two parts, one is sleep center which is present in the anterior parts of hypothalamus, and the other is wake center which is present in the ascending reticular activating system including posterior parts of hypothalamus. Idiopathic insomnia patients are said to have hyperactivity in wake center or hypoactivity in sleep center. And these patients have sleep disturbances such as inability to fall asleep, frequent awakenings and early morning wakefulness. Most patients have sleep disturbances from their childhood and after the onset of sleep disturbances, these disturbances show no improvement during all their life. Concerning about the drug treatment, probably benzodiazepin or barbiturate are effective. Because of long-term use of drugs, drug dependence and tolerance are often observed in patients. So it is necessary to take special care when choosing type or dosage level of drugs.

Humans↗
PubMed1998

[Participation of apoptosis in renal amyloidosis].

Renal amyloidosis shows symptoms of renal dysfunction due to the deposition of amyloid protein in the kidney. Recently, it was reported that apoptosis plays an important role in the pathogenesis of type-2 diabetes mellitus and Alzheimer's disease of which amyloid deposition is seen in the tissue. We investigated whether or not apoptosis and related factors are observed in renal amyloidosis. In situ nick end labeling (TUNEL) was performed in seven autopsied renal tissues with primary and secondary amyloidosis and 10 autopsied renal tissues without renal disease as the control. The number of TUNEL-positive cells was significantly increased in both the glomeruli and tubulus of the kidney with amyloidosis than in the control. Electron microscopic analysis was performed on one biopsied renal tissue with amyloidosis and six biopsied renal tissues with minor abnormalities as the control. Typical apoptotic cells were observed only in the former. Bax product, an inducer of apoptosis, and Bcl-2 protein, an inhibitor of apoptosis, were examined immunohistochemically in the seven autopsied renal tissues with amyloidosis and 10 autopsied control tissues. Bax was overexpressed in the tubulus and glomeruli of subjects with renal amyloidosis, compared to the normal controls. However, Bcl-2 protein was not detected in the glomeruli in any of the subjects examined. These results indicate that apoptotic cells are increased in number in renal amyloidosis and Bax overexpression may play an important role in this increase.

Aged↗
PubMed1998

What kind of patients are suitable for evaluating the therapeutic effect of sudden deafness?

OBJECTIVE: This study aimed to find out appropriate patients to evaluate the therapeutic effect of sudden deafness. STUDY DESIGN: The study design was a retrospective case review. SETTING: The study was performed at a university hospital. PATIENTS: A series of 443 patients with idiopathic sudden sensorineural hearing loss who visited the authors within 1 week from the onset participated. INTERVENTIONS: Relationship between interval from the onset and treatment prognosis was investigated. RESULTS: The significant difference in prognosis related to the days from the onset to the initial visit was noted only in the patients with the initial hearing level from 50-65 dB. The prognosis of the patients who visited the authors on the next day from the onset was excellent. Whereas, in the patients with initial hearing level worse than 70 dB, no significant difference in prognosis was noted among the days of visit. CONCLUSIONS: The patients with the initial hearing level worse than 70 dB and who visited the authors within 8 days from the onset were appropriate for candidates in evaluating the therapeutic effect of sudden deafness.

Adult↗
PubMed1998

[Chronic pancreatitis, acute pancreatitis].

MRCP has been recognized as a safe and noninvasive diagnostic method. In the present study we evaluated the usefulness of MRCP in diagnosis of chronic and acute pancreatitis. Two-dimensional fast asymmetric spin-echo (FASE) MRCP was performed in 40 patients with chronic pancreatitis and 13 with acute pancreatitis. In 29 patients (72.5%) with chronic pancreatitis and 9 (66.7%) with acute pancreatitis, main pancreatic duct (MPD) was visualized entirely. MRCP could demonstrate the characteristic findings of chronic pancreatitis such as dilatation and irregularity of MPD in most cases. In acute pancreatitis, MRCP indicated that MPD was normal in diameter, but irregular in configuration compared with that of the control group. MRCP may facilitate the diagnosis of chronic and acute pancreatitis.

Acute Disease↗