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Biomedical subjects

A Hashimoto

Publications and source records attributed to A Hashimoto.

At least 37 records · Page 2Linked to original sources
PubMed1992

[A useful method for the surgical treatment of active infective endocarditis--a case report using the Teflon felt reinforcing method].

In the surgical treatment for active infective endocarditis (IE), perivalvular leakage is the most severe complication. We had a 42-year-old man who had active IE and a giant vegetation in the aortic valve, and a small mycotic aneurysm in the left ventricular outflow tract. Other operative observations included slight redness and a decrease in the reflex of the annular endocardium. We made a patch closure of the mycotic aneurysm, and aortic valve replacement using the Teflon felt reinforcing method. In the postoperative course, he had a pacemaker implantation with complete AV block. Postoperative pathological examination revealed inflammatory cells and plasma infiltration, and edematous change of the interstitial tissue around the cusp surface and annular side of the resected valve. These pathological changes could explain the redness and the decrease in the reflex of the annular endocardium. The edematous changes of the annular tissue might be the cause of postoperative perivalvular leakage. Reinforcement of the prosthetic valve with Teflon felt might be a useful method to prevent perivalvular leakage. There is, however, the possibility of acceleration or elongation of infective endocarditis. In our experiences of the surgical treatment for active IE, we performed valve replacement using Teflon felt in 6 patients, and not using in 27 patients. The mean period until CRP had been normalized was no significant difference between both groups (mean days using Teflon felt were 63.5 days, and not using were 75 days).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Influence of adjuvants on the antibody specificity to the Plasmodium falciparum major merozoite surface protein, gp195.

The effect of adjuvants on the specificity of immune responses to the Plasmodium falciparum gp195 protein was investigated using adjuvant formulations based on synthetic muramyl dipeptide and monophosphoryl lipid A derivatives, in parallel with CFA and alum. Although these immunomodulators were as effective as CFA in inducing an antibody response to gp195, there were distinct differences in the recognition of B cell epitopes by these antibody populations. We have also demonstrated that MHC control of antibody specificity can be related to the adjuvant used for immunization. In general, the potency of adjuvants, their ability to induce antibodies of a particular specificity, or their ability to overcome MHC control of immune responsiveness varied independently. These findings suggest a critical role of adjuvants in the determination of the specificity of the immune response to protein Ag. Thus, the influence of adjuvants should be a major consideration in studies on immunologic recognition, as well as in the design of modern subunit vaccines.

Adjuvants, Immunologic↗
PubMed1991

Stereoselective inhibition by D- and L-alanine of phencyclidine-induced locomotor stimulation in the rat.

Bilateral injection of D-alanine, but not L-alanine, (10-100 micrograms per side for each amino acid) into the lateral ventricle reduced the increasing effect of phencyclidine (PCP, 10 mg/kg, given intraperitoneally) on locomotor activity in the rat in a dose dependent manner. This stereoselectivity agrees with the potency of these agents as agonists for the strychnine-insensitive glycine receptor in the N-methyl-D-aspartate receptor complex, suggesting that stimulation of the allosteric regulation site may antagonize the ability of PCP to produce hyperactivity.

Alanine↗
PubMed1991

D-alanine inhibits methamphetamine-induced hyperactivity in rats.

Bilateral intracerebroventricular injection of D-alanine (200-600 micrograms/rat) antagonized the ability of methamphetamine (1.0 mg/kg s.c.) to induce locomotor stimulation in the rat. In contrast, L-alanine (600 micrograms/rat) failed to affect the behavioral change induced by methamphetamine. The stereoselectivity parallels the potency of these amino acids as agonists for the strychnine-insensitive glycine binding site within the NMDA receptor complex. These results support the view that reduced excitatory amino acidergic neurotransmission may be involved in methamphetamine-induced hyperactivity.

Alanine↗
PubMed1991

Whole-cell K+ current activation in response to voltages and carbachol in gastric parietal cells isolated from guinea pig.

Patch-clamp studies of whole-cell ionic currents were carried out in parietal cells obtained by collagenase digestion of the gastric fundus of the guinea pig stomach. Applications of positive command pulses induced outward currents. The conductance became progressively augmented with increasing command voltages, exhibiting an outwardly rectifying current-voltage relation. The current displayed a slow time course for activation. In contrast, inward currents were activated upon hyperpolarizing voltage applications at more negative potentials than the equilibrium potential to K+ (EK). The inward currents showed time-dependent inactivation and an inwardly rectifying current-voltage relation. Tail currents elicited by voltage steps which had activated either outward or inward currents reversed at near EK, indicating that both time-dependent and voltage-gated currents were due to K+ conductances. Both outward and inward K+ currents were suppressed by extracellular application of Ba2+, but little affected by quinine. Tetraethylammonium inhibited the outward current without impairing the inward current, whereas Cs+ blocked the inward current but not the outward current. The conductance of inward K+ currents, but not outward K+ currents, became larger with increasing extracellular K+ concentration. A Ca(2+)-mobilizing acid secretagogue, carbachol, and a Ca2+ ionophore, ionomycin, brought about activation of another type of outward K+ currents and voltage-independent cation currents. Both currents were abolished by cytosolic Ca2+ chelation. Quinine preferentially inhibited this K+ current. It is concluded that resting parietal cells of the guinea pig have two distinct types of voltage-dependent K+ channels, inward rectifier and outward rectifier, and that the cells have Ca(2+)-activated K+ channels which might be involved in acid secretion under stimulation by Ca(2+)-mobilizing secretagogues.

Animals↗
PubMed1991

Fluoromethylated and hydroxymethylated derivatives of N-methyl-D-aspartate receptor antagonist 1-[1-(2-thienyl)cyclohexyl]piperidine.

Derivatives with fluoromethyl and hydroxymethyl groups on the cyclohexyl ring of 1-[1-(2-thienyl)cyclohexyl]piperidine (TCP), a noncompetitive antagonist of N-methyl-D-aspartate (NMDA) receptor, were tested in a radioligand binding assay to evaluate their ability to inhibit [3H]TCP binding by rat brain homogenates. The potencies of these compounds as antagonists of NMDA and L-glutamate responses were also compared using a rat cortical slice preparation. One of the analogs, cis-2-hydroxymethyl-r-1-(N-piperidyl)-1-(2-thienyl) cyclohexane (5) was found to show a high affinity (IC50 = 16 nM) for the phencyclidine (PCP) binding sites, very close to that of TCP, and to be 38-fold more potent in binding than its trans isomer. Fluoromethyl and hydroxymethyl substitutions at C4 position of the cyclohexyl ring of TCP clearly reduced the affinity by at least one order of magnitude relative to TCP.

Animals↗
PubMed1991

Natural histories of atrial septal defect with pulmonary hypertension, and ventricular septal defect with pulmonary hypertension.

A study of the natural history of 51 adult patients with atrial septal defect with pulmonary hypertension (ASD + PH) was performed. ASD + PH of less than 14 Um2 of pulmonary artery resistance (PVR) was considered an indication for surgery. The prognosis of surgically treated patients was favorable, but that of medically treated patients was poor. For patients with ventricular septal defect with pulmonary hypertension (VSD + PH), surgery was considered for pulmonary-systemic vascular resistance ratio (Rp/Rs) less than 0.5, and for patients under than 10 years and, ideally, under 2 years of age.

Adult↗
PubMed1991

Acute aortic dissection. A comparison between the results of medical and surgical treatments.

Over the last ten years 96 patients with aortic dissection were encountered in our Institute, of whom 51 had type A dissection, and 45 had type B dissection. In the patients with type A dissection the long-term survival rate was poor if they were not operated upon without delay, and the cause of death was usually rupture of the aneurysms. In the patients with acute type B dissection the surgical indication was limited and, generally speaking the long-term survival rate of the medically treated patients was more favorable.

Acute Disease↗
PubMed1991

Site-related difference in the prevalence of mitral valve prolapse. Relation to the prevalence and severity of mitral regurgitation.

In this study, 431 consecutive patients with mitral valve prolapse (MVP) diagnosed by two-dimensional echocardiography were employed to further investigate the site-related difference in the prevalence of MVP. Following echocardiographic determination of the site and severity of MVP, a pulsed-Doppler technique was further performed to assess the existence and severity of mitral regurgitation (MR) in all patients. These patients were then classified by age in 10-year groups with patients older than 60 years being enrolled in one group. The younger groups accounted for a large number of the patients with MVP in our study, with the number of patients being reduced with age. In addition, female patients tended to predominate up until the 50s, but not in the 50 and older groups. The prevalence of MVP at the centro-medial site of the anterior mitral leaflet (AML) predominated in all age groups, gradually decreasing with age, except for a peak in the 40s, before continuing to decline in the 50 and older groups. On the other hand, the prevalence of MVP at the lateral site of the AML and at the posterior mitral leaflet (PML) increased with age. In the 50 and older age groups, the prevalence of MVP at these sites increased steeply with age. However, the prevalence of MVP at both the lateral site of the AML and PML did not significantly increase with age. The trend shown above was not significantly different for gender. The number of patients with MR increased with age independent of the site of MVP. However, the prevalence and severity of MR associated with MVP at the lateral site of the AML and/or at the PML were significantly greater than at the other sites up until the 50s (p less than 0.05). When patients were older than 50 years, this significant site-related difference in the prevalence of MR was not observed because of the higher prevalence of MR in the older patients in this study. Forty-one patients could be followed for 2 to almost 5 years. Three of the 41 patients were observed to have MVP at the centro-medial site of the AML in the initial examination, but the site of MVP had extended to the lateral side of the AML in the final examination. Two patients with MVP at all 3 sites of the AML demonstrated an increase in the severity of MVP. However, there were no newly documented cases of MR among those patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1991

[A case report of chronic traumatic dissecting aneurysm of the thoracic aorta].

A 63-year-old male, who sustained a blunt chest trauma in a traffic accident, was referred to our hospital for his traumatic aneurysm. An operative repair was undertaken 3 months after the trauma. The descending aorta was dissected along 5 cm, and its diameter was about 6 cm. Graft replacement was performed under the left heart bypass by using the BioMedicus centrifugal pump. He is doing well 3 years after the operation.

Accidents, Traffic↗
PubMed1991

Pathogenicity of minute virus of canines (MVC) for the canine fetus.

Minute Virus of Canines (MVC) was shown to cause transplacental infections with embryo resorptions, especially in dams given parenteral inoculations prior to gestational day 30. Responses to oral-nasal inocula were inconsistent. Direct exposures of embryos or fetuses to MVC via the amniotic sac, however, resulted in their deaths after an incubation period of approximately 2 weeks. Virus was prominent in fetal lung and small intestinal villi, but it could not be demonstrated in fetal or uterine tissues greater than 2 weeks after the estimated time of embryonic/fetal death. With 1 exception, dams inoculated during the last trimester of pregnancy gave birth to normal pups; some pups had developed active immune responses. The exceptional dam whelped dead or dying pups with anasarca or myocarditis. Antibody levels to MVC were generally higher in dams with infected fetuses than in bitches with normal pups at term. Failures to isolate virus, or demonstrate viral antigens in tissues by immunostaining, other than near the time of embryo/fetal death, indicate the need for more sensitive viral detection methods.

Animals↗
PubMed1991

[Normolipemic xanthoma developed on alopecia lesion on a SLE patient--histological study].

A 30-year-old SLE patient developed a xanthoma on her alopecia lesion. Histological examination showed typical lupus changes including immunofluorescence stainings. In addition, there were numerous xanthoma cells existed through the dermis, interlobular spaces of subcutaneous fat tissue, perivascular areas of small blood vessels, and subendothelial spaces and inside of intraluminal thrombosis of subcutaneous small arteries. These xanthoma cells contained granular materials in their cytoplasm. Histochemically, these materials are diastase resistant P.A.S. (+), immunoglobulin (+), Sudan BB (+), Sudan III (+), Nile blue (pinkish red), and yellowish orange autofluorescence suggesting that they are lipofuscin or lipid peroxidation products. Further histological findings showed destruction of sebaceus glands and peri-glandular++ infiltration of lymphocytes and histiocytes. These histiocytes contained phagocytic neutral lipid droplets in their cytoplasm. Very small lipid peroxides were also seen on surface and/or cytoplasm of infiltrating lymphocytes existing not only peri-lobular area but also intraluminal area of blood vessels. The marker profile of these infiltrating lymphocytes are B-cell predominant admixed with some CD8(+) T-cells. These data suggest that the mechanism of developing xanthoma is initiated by immune-complex deposition on basal lamina of sebaceus glands, followed by destruction of sebaceus glands by lympho-histiocytic cells infiltration with some antigen presenting and/or effector cells, and finally xanthoma cells were developed by phagocytosis of lipid peroxides caused by macrophage-derived oxygen radicals. Interestingly, our data suggest that the lipid peroxides, which may act as photosensitizer, may leave the skin and may enter the small vessels carried by lymphocytes. Furthermore the xanthoma cells may also enter the circulation through the small arteries.

Adult↗
PubMed1991

[Three cases of minocycline-induced pneumonitis].

All three patients complained of cough, fever and dyspnea. Their chest X-ray films revealed interstitial changes such as Kerley B lines. The results of lymphocyte stimulation tests were all negative for Minocycline (MINO), whereas the provocation tests were all positive in three cases. The onsets of symptoms appeared 7, 12 and 9 hours after administration of MINO respectively, which suggested type III allergy in terms of the latency period. In cases No. 1 and No. 3, lung tissue specimens obtained by transbronchial biopsy showed findings of mild acute eosinophilic pneumonia. The bronchoalveolar lavage fluid of case No. 3 showed eosinophilia. On diagnosing MINO-induced pneumonitis, the lymphocyte stimulation test is not always beneficial, whereas the provocation test is supposed to be a safe and sure method.

Adult↗
PubMed1991

[Simultaneous replacement of the aortic valve and the ascending aorta: its operative procedure, early and late postoperative results: especially for annuloaortic ectasia and dissecting aneurysm of the aorta].

During the past 18 years, from March 1972 to February 1991, 105 patients had replacement of the ascending aorta and aortic valve. Operative techniques used in these patients, early and late postoperative results of these patients were reported. One hundred patients had composite graft replacement, and 76 patients of them were treated by Bentall's technique or its modification. Anastomotic leakages after Bentall's operation were found mostly at the bilateral coronary ostia, and incidence rate of the leakages experienced in the first 22 patients who had one lane coronary-graft anastomosis, reduced statistically significantly in patients who had two lane coronary-graft anastomosis, and also survival rate of these latter patients improved significantly than the former patients. A small caliber graft which was interposed between the coronary ostia and side holes of the composite graft was used for coronary reimplantation (Piehler's technique) in cases in which coronary ostia were not displaced cephalad, or in which dissection involved around the coronary ostial tissue even in annuloaortic ectasia. Also CABG was employed in a small number of patients. In the early postoperative results, overall operative mortality was 9.5%. In the long-term results for patients received composite graft replacement until 1989, the actuarial survival rate at 5, 10 and 14 years after surgery was 77, 66 and 60%, respectively. The actuarial survival rate for patients received composite graft replacement with two lane coronary anastomosis at 5 and 10 years after surgery was 82 and 76.2%, respectively, and this results were almost similar to the survival rate after AVR.

Aortic Dissection↗
PubMed1991

[The effect of aging on respiratory muscle function].

To elucidate the effect of aging on respiratory muscle function, the authors performed respiratory muscle function tests in 116 normal subjects. Respiratory muscle function was evaluated with maximal expiratory mouth pressure at the TLC level (PEmax) and maximal inspiratory mouth pressure at the RV level (PImax). PEmax and PImax in both sexes showed significant correlations with age. PEmax in males was significantly higher than that in females (123.6 +/- 29.7 cmH2O and 79.0 +/- 21.1 cmH2O, p less than 0.01, respectively). PImax in males was also significantly higher than that in females (98.4 +/- 26.0 cmH2O and 71.9 +/- 26.4 cmH2O, p less than 0.01, respectively). PEmax correlated significantly with TLC, and PImax showed a significant inverse correlation with RV/TLC. Furthermore, there was a significant inverse correlation between RV/TLC and age. Our data suggest that inspiratory muscle weakness in aging may be responsible for the increase in RV/TLC.

Adult↗
PubMed1991

[An emergent aortic and mitral valve replacement for active infective endocarditis preoperatively using extracorporeal ultrafiltration method].

We reported a 29-year-old man with active endocarditis complicating aortic and mitral valve regurgitation. The echocardiogram showed a mycotic aneurysm at aortic valvular annulus and a aneurysm of mitral valve. Heart failure was progressive and caused anuria. Prior to emergent double valve replacement, 2,500 ml of water was removed. Then hemodynamics became stationary. Urination was good during and after operation. In this case, complicating acute renal failure, dehydration with extracorporeal ultrafiltration method was very effective for improvement of hemodynamics.

Adult↗