PubMed Health⌕ Search

Biomedical subjects

M Hara

Publications and source records attributed to M Hara.

At least 613 records · Page 34Linked to original sources
PubMed1993

Expression and relationships of seven public idiotypes of DNA-binding autoantibodies on monoclonal antibodies and serum immunoglobulins.

Many studies have shown that DNA-reactive autoantibodies share cross-reactive public idiotypes that are defined, usually, by single anti-idiotype reagents. Because anti-idiotype antibodies or antisera will be limited in their ability to detect all the idiotopes of a particular antibody, their use will tend to underestimate the full extent of idiotype sharing between different antibodies. In order to define more comprehensively the extent of idiotype sharing in DNA autoantibodies, a panel of DNA-binding monoclonal autoantibodies from lupus mice was examined with a range of anti-idiotype antisera prepared in rabbits (five sera), guinea pigs (four sera) and a sheep. Each idiotype was detected on more antibodies than its original reference monoclonal antibody, and idiotopes of each were also present on serum immunoglobulins from lupus mice. Of 23 monoclonal antibodies 65% reacted with one or more of the anti-idiotype reagents. On these criteria, all the idiotypes were public; none was private in its expression. In about half the cases the idiotypes were located in or near the antigen-binding sites of the antibodies, but a direct relationship to specificity was not obvious except in the case of Id.228 present on antibodies with a relatively high affinity for single-stranded DNA. In other cases there was no obvious relationship between idiotype and specificity. Antibodies from the same mouse did not each express the same array of idiotopes.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1993

Activation of CYP11A and CYP11B gene promoters by the steroidogenic cell-specific transcription factor, Ad4BP.

We have examined the transcriptional activity of four cis-elements, Ad1(CRE), Ad2, Ad3, and Ad4, that are present in the promoter of the bovine CYP11B (11 beta-hydroxylase P-450) gene using beta-globin reporter gene constructs and transient transfection into steroidogenic and nonsteroidogenic cell types. Only Ad1(CRE), a CRE homolog, showed forskolin-dependent transcriptional activity in adrenal tumor Y-1 cells, whereas the other elements were not able to stimulate transcription by themselves. As Ad3 and Ad4 had previously been identified as the cis-elements required for full cAMP-dependent transcription of this gene, we examined the effect of combinations of different cis-elements on the transcription of the reporter gene. In Y-1 cells, Ad1(CRE) and four tandem copies of any one of the other cis-elements substantially activated transcription in response to forskolin treatment. The template carrying Ad1(CRE) and Ad4 was also active in testicular Leydig cells, I-10, whereas it was inactive in nonsteroidogenic PC-12 cells. Transcriptional activation by the 4xAd4/Ad1(CRE) combination presumably depended on the presence of Ad4-binding protein (Ad4BP), which is absent in PC-12 cells, as shown by immunoblot analysis. This was confirmed by cotransfecting an expression vector for Ad4BP into PC-12 cells, which caused forskolin-dependent transcription to increase in proportion to the amount of expression vector. In Y-1 cells, transcriptional activation by forskolin was mimicked by cotransfection of an expression vector for the catalytic subunit of protein kinase-A.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Gland Neoplasms↗
PubMed1993

Suppression of ventricular premature contractions continues after the washout of antiarrhythmic drugs.

The effects of the washout of antiarrhythmic drugs on the frequency of ventricular premature contraction (VPC) were investigated in 64 patients (VPCs > 2000/day). Included were patients on mexiletine (300-600 mg/day; 23 patients), disopyramide (300-600 mg/day; 19 patients) and atenolol (50 mg/day; 22 patients). Holter monitoring was repeated before, during and after the treatment with the above 3 drugs and the efficacies of the drugs were evaluated based on the spontaneous variability before the treatment. VPC reduction exceeding the calculated spontaneous variability during drugs therapy (drug-responders) and after the washout of the drugs (wash-responders) was noted in 17 (63%) and 3 (13%) of the mexiletine group; 11 (58%) and 5 (26%) of the disopyramide group; and 13 (59%) and 8 (36%) of the atenolol group, respectively. For the entire group of 64 patients, wash-responders were noted significantly (p < 0.05) more among drug-responders (14 of 41 patients; 34%) than drug-nonresponders (2 of 23 patients; 9%). Therefore, the antiarrhythmic effects of drugs observed during drugs therapy seem to continue even after the discontinuation of antiarrhythmic drugs in 34% of patients those whose VPC reduction exceeded the spontaneous variability (drug-responders).

Adult↗
PubMed1993

Solitary pancreatic metastasis from renal cell carcinoma.

A rare case of resectable solitary pancreatic metastasis from a renal cell carcinoma is reported. The patient was a 57-year-old man who presented with epigastralgia. He had undergone a radical nephrectomy of the right side 30 months previously. The diagnosis of pancreatic metastasis was based on the patient's past history and angiographic demonstration of typical hypervascular tumor staining. Histological examination was confirmatory. The patient was successfully treated by pancreaticoduodenectomy followed by alpha-interferon administration. As of 6 months after surgery, he remains well.

Carcinoma, Renal Cell↗
PubMed1993

Pure progressive autonomic failure presenting severe orthostatic hypotension.

A 59-year-old woman showed chronic progressive autonomic failure consisting of orthostatic hypotension and dyshidrosis. No signs of Parkinsonism, cerebellar or peripheral neuropathy were observed. Autonomic nervous function tests and findings of biopsied sural nerve suggested that this case had both sympathetic and parasympathetic dysfunctions, mainly postganglionic. A decrease in the total peripheral resistance and no increase in the heart rate on standing seemed to be the mechanism of orthostatic hypotension in this case. We conclude that pure PAF can be recognized as a distinct clinical syndrome of systematic degeneration of the autonomic nervous system.

Autonomic Nervous System Diseases↗
PubMed1993

Amelanotic acral melanoma masquerading as fibrous histiocytic tumours. Three case reports.

We report 3 cases of amelanotic melanoma developing on the finger, whose histology disclosed dermal invasion of histiocyte-like tumour cells. One of the 3 cases was subungual melanoma and the other 2 were on the volar surface of the finger tip. Because of the characteristic dense infiltration of large histiocyte-like tumour cells, including many multinucleated giant cells, we initially considered histiocytic tumours. However, there were some histiocyte-like cells that displayed inclusion-like intranuclear invagination of cytoplasm, and almost all tumour cells, including the giant cells, were positive for S-100 protein. In addition, ultrastructural demonstration of premelanosomes within the cytoplasm of the tumour cells established the diagnosis of amelanotic melanoma. These features were distinct histologically from other variants of vertical growth phase amelanotic malignant melanoma, including desmoplastic or neurotropic melanoma. Because we encountered cases 2 and 3 within just a year after the first case, we think that the misdiagnosis of amelanotic "histiocytic" melanoma can be avoided through enhanced clinical awareness and subsequent appropriate histopathologic studies.

Aged↗
PubMed1993

Regulation of Cl- conductance in delayed shortening and shrinkage of outer hair cells.

Tetanic electrical field stimulation induces slow and delayed shortening of isolated outer hair cells (OHCs) from guinea pigs concomitant with a decrease in cell volume and intracellular Cl- concentration ([Cl-]i). These responses are dependent on the entry of Ca2+ and the activation of both Ca(2+)-activated K+ channels and furosemide-sensitive Cl- channels. In this study, the regulatory mechanisms of the Cl- channels of OHCs were investigated. Tetanic stimulation induced shrinkage and a decrease in [Cl-]i, the latter being unrelated to the activity of the Na+/K+/2Cl- cotransporter. These responses were inhibited by tetraethylammonium, and the inhibition was overcome by an increase in the K+ conductance by valinomycin, though valinomycin alone did not affect the resting cell volume and [Cl-]i. The deprivation of extracellular Ca2+ inhibited the stimulation-induced changes in volume and [Cl-]i even in the presence of valinomycin. These results suggest that electrical stimulation-induced delayed shortening and shrinkage of OHCs are induced by Cl- efflux, which is electrically coupled to K+ efflux and independently activated following an increase in intracellular Ca2+ concentration.

Animals↗
PubMed1993

Cerebellopontine angle medulloblastoma: case report and literature review.

The occurrence of cerebellopontine angle (CPA) medulloblastoma is a rare phenomenon. We report such a case in a 19-year-old girl who had 6th and 8th cranial nerve palsies as well as cerebellar dysfunction. The tumour arose from the left flocculus or adjacent cerebellar hemisphere and projected into the CPA. She was treated by subtotal removal of the tumour, followed by entire neuroaxis irradiation and immunochemotherapy. The clinical characteristics and pathogenesis of CPA medulloblastoma are reviewed and discussed.

Adult↗
PubMed1993

Epidemiological study on poliovirus isolates from patients with acute flaccid paralysis in Shandong province in China.

In five years from 1988 to 1992, 51 polioviruses were isolated from patients with acute flaccid paralysis in Shandong province in China. Of the 51 poliovirus isolates, 17 were type 1, 18 type 2 and 16 type 3. Twelve type 1 viruses isolated during the period from 1988 to 1990 were shown to be wild strains by serology and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. These wild strains were classified into three groups by PCR-RFLP. The other type 1 isolates were Sabin-like strains. No wild strain was isolated in 1991 or 1992. All isolates of types 2 and 3 during the five years were Sabin-like strains. These data suggest that wild strains of polioviruses will soon be eradicated in Shandong province.

Acute Disease↗
PubMed1993

[Serial changes in QT interval during acute myocardial infarction: comparison of QT interval changes of reperfused cases and non-reperfused cases].

The serial changes in QT intervals during the course of acute myocardial infarction are of interest from the standpoint of the electrocardiogram itself, the development of ventricular tachyarrhythmias, residual cardiac function, and the prognosis of the patients. However, only sparse literature has dealt with this issue because it is difficult to obtain ECGs for analysis, and multiple factors influence the QT interval including the degree of reperfusion, electrolyte imbalance, hemodynamic changes and drugs which alter the QT interval. The ECGs of patients with acute myocardial infarction who underwent reperfusion therapy were analyzed: Sixteen consecutive patients were enrolled in this study, 9 with TIMI grade II and III (TIMI: the thrombolysis in myocardial infarction study group criteria) and 7 with TIMI grade 0, myocardial infarction with (9) and without (7) reperfusion. Patients with collaterals, TIMI grade I, hypertrophic cardiomyopathy, electrolyte imbalance, Ia antiarrhythmic drugs, beta adrenoreceptor blockades, atrial fibrillation, and intraventricular conduction disturbances were excluded from the study. Serial ECG recordings were performed at 3, 6, 9, 12, 24, 48, and 72 hours after the onset of myocardial infarction. One week after and one month after the onset, the ECGs were recorded. Patients who exhibited reocclusion on their arteriograms in the chronic phase were also excluded from the study. Measurements of the QT intervals were performed at the ischemic lead (II in the standard limb lead in inferior infarction and V2 in anteroseptal infarction), and values were averaged from 5 consecutive QRS complexes according to Lepeschkin's method and corrected using Bazett's method. The left ventricular ejection fraction (LVEF) and percent fractional shortening (FS) in segments 2, 3, 4 or 5 were calculated from the ventriculogram in the chronic phase. The QT interval revealed a lengthening with its peak within 12 hours after the onset and it became shorter thereafter in reperfused patients. In patients without reperfusion, the QT interval became progressively prolonged without showing a peak point, up to one month. LVEF and FS were significantly higher values in patients with reperfusion than in those without reperfusion. In conclusion, in patients with reperfusion, the QT interval was transiently prolonged and later shortened with improved LVEF and FS than in patients without reperfusion.

Adult↗
PubMed1993

[Effective dose of flecainide for arrhythmia in children].

Nine children with arrhythmia (1 automatic atrial tachycardia, 1 premature ventricular construction, and 7 ventricular tachycardia) who started oral treatment using flecainide were studied. All but 2 cases (1 post operative ventricular septal defect, 1 post operative tetralogy of Fallot) had ostensibly normal heart on physical examination, chest X ray and echocardiogram. To raise serum level above 200ng/ml, flecainide dose over 80mg/m2 or 3mg/kg was needed. There was negative correlation between dose (y: mg/kg) and age (x: year) (y = 5.2-0.16x, r = 0.88) in this group. No serious side effect indicating the need to discontinue further medication was detected. In electrocardiogram, PR, QRS and QT interval was not changed before or after the medication. Premature ventricular contraction disappeared in 2 of 8 cases (25%), decreased in number in 3 (38%), did not change in 1 (13%) and increased in number in 2 (25%). However ventricular tachycardia rate decreased or disappeared in all of the 5 cases whose ventricular tachycardia was detected in Holter electrocardiogram. Flecainide seems more effective for sustained ventricular tachycardia than for nonsustained ventricular tachycardia.

Administration, Oral↗
PubMed1993

[A case report of epithelioid hemangioendothelioma of the lung].

A 15-year-old woman presented with an abnormal chest X-ray taken at a medical check up. Her chest X-ray disclosed multiple nodular shadows in bilateral lung fields. A transbronchial biopsy was non-diagnostic and an open biopsy was performed. The tumor was histologically diagnosed as epithelioid hemangioendothelioma on the basis of associated with immunoreactivity to factor-VIII related antigen by immunohistochemistry and the presence of Weibel-Pallade bodies on electron microscopy. She has been followed-up in her home town without significant change.

Adolescent↗
PubMed1993

[Histological study in renal grafts--macrophages population in renal grafts].

We studied about the histological findings of the kidneys including of the infiltrated macrophages in one hour post-transplantation kidney biopsies (one hour biopsies) and re-biopsies on 11 patients. They were transplanted at 4-28 (ave. 15.1 +/- 3.8) years of age. The periods from transplantation to this study were 1.0-7.3 (ave. 3.3 +/- 1.9) years. 6 patients had acute rejections, and their renal function became normal after treatments. At this study, all grafts survived, and the patients had no abnormal findings except two (one had proteinuria, another had proteinuria and mild elevation of serum creatinine level). But histologically, five patients had chronic rejections among the 8 patients who had re-biopsies more than one year after transplantation. And we experienced 6 patients whose kidney had mesangial IgA deposits in one hour biopsies and 3 patients who had de novo type glomerulonephritis in re-biopsies (IgA neuropathy in 2 patients, membranous nephropathy in one). In one hour biopsies, the populations of macrophages in the interstitium were 4.18 +/- 2.84/mm2 in the patients who would have acute rejections (6 patients), 1.38 +/- 1.13/mm2 in the cases who would not have. It was suspected that the increase of the infiltrated macrophages in the interstitium in one hour biopsies could predict acute rejections. In re-biopsies, many macrophages infiltrated in the interstitium (8.34 +/- 4.86/mm2), particularly on patients who had chronic rejections.

Adolescent↗
PubMed1993

[Clinical study of patients with nocturnal asthmatic attacks admitted to an emergency room].

Over the periods of a year, we studied the patients who were admitted to the emergency room at our hospital at night with asthmatic attacks. From July 1991 to June 1992, 10,932 patients were admitted to the internal department of our emergency room, 707 (6.5%) of them because of asthmatic attacks. These 707 consisted of 364 patients (51.5%) with mild attacks, 242 (34.2%) with moderate attacks and 101 (14.3%) with severe attacks according to Mitsui's score. Most patients admitted before 23:00 and after 5:00, but more patients with severe attacks were admitted around midnight. A large part of the patients with moderate or severe attacks had chronic hypoxemia, and more than half of the patients' serum theophylline concentration was under the therapeutic rate. More than half patients were treated within 5 minutes. But within those who were not, 6 patients with mild attacks on admission needed hospitalization later. For prevention of life threatening attack, we should regard it as an important problem to follow up the patients who don't come to the hospital in the daytime in spite of frequent visits to the emergency room at night.

Asthma↗