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Y Kohda

Publications and source records attributed to Y Kohda.

At least 19 recordsLinked to original sources
PubMed1997

Alpha-melanocyte-stimulating hormone protects against renal injury after ischemia in mice and rats.

Reperfusion after ischemia induces cytokines, chemoattractant chemokines, adhesion molecules, and nitric oxide (NO). The resultant neutrophil adherence and NO potentiates renal injury. alpha-Melanocyte-stimulating hormone (alpha-MSH) is a potent anti-inflammatory agent that inhibits neutrophil migration and production of neutrophil chemokines and NO. Since neutrophils and NO promote renal ischemic injury, we sought to determine if alpha-MSH inhibits renal injury in a model of bilateral renal ischemia. alpha-MSH significantly reduced ischemia-induced renal damage, measured by changes in renal histology and plasma blood urea nitrogen and creatinine in mice. alpha-MSH significantly decreased tubule necrosis, neutrophil plugging, and capillary congestion. Delay of alpha-MSH treatment for 6 h after ischemia also significantly inhibited renal damage. alpha-MSH also significantly inhibited ischemic damage in rats. To begin to determine the mechanism of action of alpha-MSH, we measured its effects on mediators of neutrophil trafficking and induction of the inducible isoform of NO synthase-II. alpha-MSH inhibited ischemia-induced increases in mRNA for the murine neutrophil chemokine KC/IL-8. alpha-MSH also inhibited induction of mRNA for the adhesion molecule ICAM-1, which is known to be critical in renal ischemic injury. alpha-MSH inhibited nitration of kidney proteins and induction of NO synthase-II. We conclude: (a) alpha-MSH protects against renal ischemia/reperfusion injury; and (b) it may act, in part, by inhibiting the maladaptive activation of genes that cause neutrophil activation and adhesion, and induction of NO synthase.

Animals↗
PubMed1996

Dynamic changes of cathepsins B and L expression in the monkey hippocampus after transient ischemia.

Enzymatic activities, expressions, and the immunohistochemical localization of lysosomal cystein proteases, cathepsins B and L, were analyzed in the monkey hippocampus after transient ischemia to clarify the mechanism of delayed cornu Ammonis (CA)-1 neuronal death. By enzymatic assay, the activity of cathepsin B increased in CA-1, 24 h after the ischemic insult, while that of cathepsin L decreased. On Western blotting, the protein contents of both cathepsins B and L increased immediately after ischemia. By immunohistochemistry, cathepsins B and L were stained as coarse granules in the perikarya of control CA-1 neurons, but in postischemic CA-1 neurons they were released from lysosome granules. In contrast, in CA-2 and the remaining sectors, enzymatic activities increased after ischemia, and immunoreactivities of cathepsins B and L increased only within lysosome granules. These results suggest that cathepsins B and L may play an important role in the breakdown of certain cell proteins in the postischemic CA-1 neurons.

Animals↗
PubMed1996

Contrast-enhanced MRI of intrasellar arachnoid cysts: relationship between the pituitary gland and cyst.

We recently encountered two large intrasellar arachnoid cysts extending to the suprasellar region. The intensity of the cyst contents was identical to that of the cerebrospinal fluid on both T1- and T2- weighted MRI. On contrast-enhanced MRI, the pituitary gland was compressed posteroinferiorly and flattened in the sella turcica. In this report of rare intrasellar arachnoid cysts the discussion is focused on dislocation of the pituitary gland.

Arachnoid Cysts↗
PubMed1996

Expression of NF2 gene product merlin in arachnoid villi and meningiomas.

Neurofibromatosis type 2 (NF2) gene encodes a novel 595 amino acid protein named merlin. Recently, Ruttledge et al demonstrated inactivation of NF2 gene in approximately 60% of sporadically occurring meningiomas. Merlin is thought to physiologically exist beneath the cell membrane, and to form a part of modulation in signal transduction, for example, information concerning contact inhibition. In NF2-related tumors, it is supposed that the mutation of merlin results in loss of this signal transduction leading to tumorigenesis. In this paper, we investigated the expression of NF2 gene product merlin in arachnoid villi and meningiomas. The immunohistochemical staining of merlin showed a striking contrast between arachnoid villi and meningiomas. In arachnoid cells, merlin was labeled in the whole cytoplasm, but not within the nuclei. In contrast, in meningiomas, immunoreactivity of merlin was mainly seen in the nuclei. These results suggest that arachnoid cells with normal merlin are capable of normal signal transduction, whereas meningioma cells with mutated merlin show impairment of signal transduction which may lead to tumorigenesis.

Arachnoid↗
PubMed1995

Prolongation of epidural anesthesia in the rabbit with the use of a biodegradable copolymer paste containing lidocaine.

Prolongation of the drug effect using a drug-delivery system has recently been introduced in local anesthesia. In this study, we investigated the prolonging effect of an epidurally injected biodegradable copolymer paste containing 10% lidocaine (Lid-CoPol). Twenty-nine rabbits were studied. A catheter was placed in the epidural space at the level of L6-7 in each animal. A solution of 10% lidocaine (Group I, n = 12), or a copolymer containing 10% lidocaine (Lid-CoPol), (Group II, n = 12) or copolymer paste only (Group III, n = 5) was injected epidurally at a dose of 0.15 mL/kg. The effect of each drug was assessed by evaluation of response to pain stimulation and of the degree of motor block produced. The plasma lidocaine concentration was also measured consecutively in five animals of both Groups I and II. The duration of sensory and motor block of Lid-CoPol was 800% and 975% longer, respectively, than that of plain lidocaine solution. Plasma lidocaine concentration reached a maximum 5 min after injection (5.5 +/- 0.5 micrograms/mL) in Group I. In Group II, the level reached a maximum 30 min after injection (3.7 +/- 1.5 micrograms/mL). The findings are attributed in part to the slow release of lidocaine from the biodegradable copolymer paste, which is suggested as a new drug-delivery system for local anesthetics.

Anesthesia, Epidural↗
PubMed1995

[Valproic acid].

Explore the source record for details and available documents.

Adult↗
PubMed1994

Production of two novel monoclonal antibodies against human renal glomeruli and their application to the immunohistochemical investigation of crescentic glomerulonephritis.

Two monoclonal antibodies (MAbs) against human renal glomeruli, HEP1 and HBM1, were produced using isolated human glomeruli as an antigen. Immunohistochemical and immunoelectron microscopic analyses revealed that the recognition site of HEP1 is the cell surface of the visceral glomerular epithelial cells. HEP1 showed no reaction in the renal interstitium or in other tissues. HBM1 recognized an antigen present in the basal lamina of the renal glomeruli, Bowman's capsule, and partly in the basement membrane of renal tubules, but it was not reactive with the mesangial matrix or renal interstitium. The isotype of both MAbs was IgG1, k. The molecular weights of their corresponding antigens were 127-177 and 220 kD, respectively. Besides human tissues, HEP1 also showed cross-reactions with antigens in the visceral glomerular epithelial cells of various animals other than mice. HBM1 recognized human antigen only. Using both MAbs, eight cases of crescentic glomerulonephritis were examined immunohistochemically. As a result, it was demonstrated that the crescents may not be formed by visceral glomerular epithelial cells. From this study, these two MAbs appear to be useful markers for the evaluation of renal glomerular disorders.

Animals↗
PubMed1994

Determination of 17-hydroxycorticosteroids in dialysate solution as a measure of adrenocortical function in hemodialysis patients.

Dialysate contents of 17-hydroxycorticosteroids (17-OHCS) in hemodialysis patients were studied as a potential measure of adrenocortical function. Dialysate 17-OHCS contents after a 2-day interval of hemodialysis in 15 hemodialysis patients were determined. Dialysate 17-OHCS increased after intravenous injection of cortisol the evening prior to hemodialysis (n = 4). Dialysate 17-OHCS content was suppressed, as was plasma cortisol, after a standard dexamethasone (Dex) suppression test (n = 1). Their plasma cortisol was suppressible or nonsuppressible by an overnight Dex suppression test, as reported previously. However, basal dialysate 17-OHCS contents were not different between them, indicating that the nonsuppressible patients with overnight Dex seem not to have hypercortisolism. We conclude that determination of dialysate 17-OHCS seems a useful noninvasive technique for the evaluation of adrenocortical function in hemodialysis patients.

17-Hydroxycorticosteroids↗
PubMed1994

Crude drugs from aquatic plants. IV. On the constituents of alismatis rhizoma. (2). Stereostructures of bioactive sesquiterpenes, alismol, alismoxide, orientalols A, B, and C, from Chinese alismatis rhizoma.

Following the characterization of the triterpene constituents in Chinese Alismatis Rhizoma, we investigated the chemical structures of orientalols A, B, and C, isolated from the less polar fraction of the crude drug together with two known sesquiterpenes, alismol and alismoxide. On the basis of the chemical and physicochemical evidence, the structures of orientalols A, B, and C have been determined and those of alismol and alismoxide were revised. All five sesquiterpenes were found to show an inhibitory effect on the contraction of isolated bladder smooth muscle induced by carbachol.

Animals↗
PubMed1993

[Transcatheter hepatic segmental chemo-Lipiodol-embolization against hepatocellular carcinoma accompanied by tumor thrombosis in the portal vein].

We performed transcatheter hepatic segmental chemo-Lipiodol-embolization against hepatocellular carcinoma accompanied by tumor thrombosis in the portal vein. CT scan after embolization demonstrated good Lipiodol accumulation in the tumor thrombosis in some cases. In one resected case, remarkable necrosis of tumor thrombosis was proved histologically. In five non-resected cases, 6-month survival rate was 100%. We hope this therapeutic method can be useful for hepatocellular carcinoma with tumor thrombosis in the portal vein.

Aged↗
PubMed1993

[Effect and complications of embolization therapy using absolute ethanol for renal arteriovenous malformation].

Transcatheter embolization therapy using absolute ethanol was accomplished in six patients with renal arteriovenous malformation. The effect of this therapy was considered to be good, because none of the patients has experienced recurrent hematuria. It is necessary to avoid the back flow of absolute ethanol. One patient had the particular complication of hydronephrosis caused by the incidental injection of absolute ethanol into the ureteral artery.

Adult↗
PubMed1993

[Study on human diseased thyroid cells in collagen gel culture--morphology and their malignancy of cultured colonies].

Thyroid cells from 14 normal subjects, two patients with Grave's disease, four patients with follicular adenoma and eight patients with papillary carcinoma were cultured in collagen gel. The colonies of these cells were stereoscopically observed and their morphological characteristics were studied with regard to relation with pathological findings of mother tumor, extra-capsular invasion and metastatic potential. For normal thyroid, Grave's disease and follicular adenoma (except for one case), their own characteristic branching type colonies were found. For papillary carcinoma, both branching type and spheroid type of colonies were observed. The ratio of branching type/spheroid type varied individually in the patients with papillary carcinoma. However, the spheroid type was found to trend to be predominant in patients with extra-capsular invasion and/or lymph node metastasis. This means that the observation of spheroid type colonies in collagen gel is suggestive of risk of extra-capsular invasion or lymph node metastasis. From the obtained results, it seemed possible to diagnose poorly-differentiated cells in vitro by morphologically observing colonies of human thyroid papillary carcinoma cells developing in collagen gel.

Adenoma↗
PubMed1993

[A new departure of an incorporated round visits; anesthesiologists and pharmacists ].

We commenced a new trial of an incorporated round visit. Members of round visit are 4 anesthesiologists and 2 pharmaceutists. This new trial gives us the following advantages; 1. We can get the newest drug informations at bed side during the round visit. 2. We can select a more reasonable therapy for patients through discussions. 3. Cooperative development of clinical studies concerning a new model or style of drugs may be possible. This new style of round visit is also of benefit for patients because it leads to administration of more pertinent drugs. We recommend to have a chance of cooperation between anesthesiologists and pharmaceutists in other hospitals.

Anesthesia Department, Hospital↗
PubMed1991

Pharmacokinetics of ambenonium, a reversible cholinesterase inhibitor, in rats.

The pharmacokinetics of ambenonium, a reversible cholinesterase inhibitor, in rats was investigated following intravenous administration of the drug. Mean residence time and steady state volume of distribution were 23-36 min and 0.20-0.311 kg-1, respectively, and were dose independent at the dose of 0.3-3 mumole kg-1. Total body clearance of 8.2 ml min-1 kg-1 over 0.3 mumole kg-1 was slightly increased to 11.3 ml min-1 kg-1 at 3 mumole kg-1. Renal clearance was also increased with the increase of the dose, while hepatobiliary clearance was substantially constant. Ambenonium was highly concentrated in the liver, kidney, spleen, and lung. About 30 per cent of the dose is concentrically stored in the liver at 6 h after administration, and had not disappeared after 24 h.

Ambenonium Chloride↗
PubMed1991

[Development and evaluation of the comment aid system for therapeutic drug monitoring. I. Application to valproate].

A comment aid system for therapeutic drug monitoring (TDM), which produces the primary comment on the dosage regimen of valproate, was developed. This system produces consulting comments with a fuzzy theory, by using the dosage regimen of valproate, pharmacokinetic parameters estimated by the Bayesian method, and therapeutic effect and toxicity of anticonvulsants evaluated by the physician. For nearly 90% in 42 cases, comments of the system were agreeable comparing with the notes of TDM technologists. There are a few disagreements between this system and experts, mainly because the system does not use enough information about combination therapy with other anticonvulsants. Developed comment aid system shows some clinical and educational utility, and suggests significance and possibility of more useful and al around TDM expert system. Then this system might be available as a prototype of the TDM expert system.

Adolescent↗
PubMed1989

[A successful case of localized aortic dissection associated with bicuspid aortic valve].

It is known that bicuspid aortic valve is a risk factor of aortic dissection in Europe and America, but there is no report of the case in Japan. A 47-year-old male teacher of senior high school had an abrupt onset of chest pain. Aortogram showed localized dissection of the ascending aorta and moderate degree of aortic regurgitation. Cold cardioplegic arrest with moderate systemic hypothermia was used under cardiopulmonary bypass. The aortic valve was bicuspid and localized transverse intimal dissection was also found above left-sided commissure. As both cusps were soft and not degenerative, mattress sutures were used to support the prolapsed cusps against the outer aortic wall. The ascending aorta was replaced with a prosthetic vascular graft. Postoperative clinical course was uneventful and he is doing well two years after the surgery. The bicuspid aortic valve and aortic dissection were also discussed.

Aortic Dissection↗
PubMed1989

[A case of abdominal actinomycosis following foreign body in the stomach wall].

Recently abdominal actinomycosis is rare. Its diagnosis is difficult because it resembles malignant diseases. We reported a case of abdominal actinomycosis considered to be of the stomach origin and attempted to correlate the radiological findings with the pathological features referring to the previous reports.

Actinomycosis↗