Search PubMed⌕ Search

Biomedical subjects

Y Hashimoto

Publications and source records attributed to Y Hashimoto.

At least 577 records · Page 32Linked to original sources
PubMed1997

Distribution of free and conjugated morphine in body fluids and tissues in a fatal heroin overdose: is conjugated morphine stable in postmortem specimens?

The tissue distribution of free and conjugated morphine in a male individual who died after self-injection of heroin and methamphetamine was investigated, and the postmortem stability of morphine in the blood, liver and urine, and that of 6-monoacetylmorphine in the urine was determined. Confirmation and quantitation of morphine, 6-monoacetylmorphine and methamphetamine were performed by gas chromatography/mass spectrometry and gas chromatography, respectively. Blood levels of free and total morphine were very site-dependent with ranges of 462-1350 and 534-1570 ng/mL, respectively. Large amounts of total morphine, 5220, 4200, and 2270 ng/g, had accumulated in the stomach contents, liver, and lung, respectively. The concentration of free morphine in the cerebrospinal fluid was correlated very closely with that in the cerebrum. The proportion of free morphine in various fluids and tissues ranged from 23.0% to 98.8% of total morphine: less than 30% in the stomach contents and urine; 30-60% in the liver, cerebrospinal fluid, lung, and pericardial sac fluid; 61-90% in the spleen, right femoral muscle, myocardium, blood in the left and right ventricles of the heart, and right femoral vein blood; more than 91% in the right kidney and cerebrum. Detectable amounts of 6-monoacetylmorphine, 417 ng/mL and 78 ng/g, existed in the urine and stomach contents, respectively, indicating that this individual might have died within several hours after heroin injection. Methamphetamine concentrations in the blood were also site-dependent within the range 551-1730 ng/mL. In an in vitro experiment, free and conjugated morphine were stable in the blood and urine at 4, 18-22, and 37 degrees C for a 10-day study period. In the liver, however, conjugated morphine had been converted almost completely to free morphine at 18-22 and 37 degrees C by the end of the experiment, although it was stable at 4 degrees C. Urine 6-monoacetylmorphine, although degraded slightly at 37 degrees C, was stable at 4 and 18-22 degrees C during the experiment. Thus it appears that non-specific hydrolysis of conjugated morphine to free morphine would not occur in corpses at least for a few days after death. Femoral muscle may be a specimen of choice for roughly predicting the ratio of free to total morphine in blood even when blood specimens are not available, because the femoral muscle is relatively spared of both postmortem diffusion of drugs and bacterial invasion.

Adult↗
PubMed1997

Distinctive expression of filaggrin and trichohyalin during various pathways of epithelial differentiation.

Filaggrin and trichohyalin are keratin intermediate filament-associated proteins, and are primarily expressed in the granular cells of the epidermis and in the inner root sheath cells of the hair follicles, respectively. These two proteins are, however, occasionally co-expressed in some tissues. To gain more insights into the mechanisms for expression and processing of (pro)filaggrin and trichohyalin during various pathways of epithelial differentiation, we compared their localization by double immunostaining techniques in normal and psoriatic epidermis, tongue filiform papillae and cultured human epidermal keratinocytes. In normal foreskin, trichohyalin immunoreactive cells were observed only occasionally and, when present, they always co-expressed filaggrin. Trichohyalin expression occurred, however, in filaggrin-negative cells as well as in filaggrin-positive cells in the psoriatic epidermis, tongue papillae and cultured keratinocytes. Filaggrin and trichohyalin were induced independently at different times following calcium shift in cultured keratinocytes. Immunoelectron microscopy demonstrated the distinct intracellular distribution of filaggrin and trichohyalin. Some filaggrin granules were observed in the cells where trichohyalin was diffusely distributed. Likewise some trichohyalin granules were found in the cells with diffuse filaggrin labelling. These results suggest the existence of distinct expression/processing mechanisms of filaggrin and trichohyalin in differentiating keratinocytes.

Adult↗
PubMed1997

[Vitreous surgery for macular hole followed membrane peeling].

We performed vitreous surgery for macular holes following membrane peeling. The cases were five eyes of five females aged 42 to 67 years at the time of membrane peeling, out of 441 eyes of 414 patients who underwent membrane peeling. One eye had secondary epiretinal membrane combined with ocular sarcoidosis, two eyes had idiopathic epiretinal membrane, and two eyes had idiopathic vitreoretinal traction syndrome. The presumed interval from membrane peeling to macular hole formation was 5 to 90 months (average 14 months). For treatment of the macular holes, membrane peeling and SF6 gas tamponade were performed. In four eyes of the five eyes, the macular hole was closed. In the remaining eye, removal of the retinal pigment epithelium from the base of macular hole and application of fibrin glue were used in addition to SF6 gas tamponade, but the macular hole was not closed. The follow-up term was 10-24 months (average 17.6 months). Geometrical mean visual acuity was 0.34 before membrane peeling, 0.94 at maximum after membrane peeling, 0.19 after macular hole formation, 0.51 at maximum after macular hole surgery, and 0.44 at the final visit.

Adult↗
PubMed1997

Duplex carotid sonography in distinguishing acute unilateral atherothrombotic from cardioembolic carotid artery occlusion.

PURPOSE: To distinguish between acute complete unilateral cardioembolic and atherothrombotic internal carotid artery (ICA) occlusion by using duplex carotid sonography. METHODS: We studied 11 patients with cardioembolic ICA occlusion (CE group), 32 patients with atherothrombotic ICA occlusion (AT group), and 25 patients with normal angiographic findings (control group). We obtained B-mode scans and measured the end-diastolic flow velocity (EDV) in both common carotid arteries within 3 days of the onset of symptoms. Side-to-side ratios of EDV (ED ratio) were calculated by dividing the flow velocity on the unaffected side by that on the affected side. RESULTS: In the AT group, the proximal ICA was full, with a large area of heterogeneous and partially calcified plaque, and the EDV (10.9 +/- 6.1 cm/s) was significantly lower than that in the control group (20.3 +/- 6.0 cm/s). The ED ratio was greater than 1.4 in all but one patient. In three patients in the CE group, B-mode scans showed a mobile, echogenic intravascular structure in the proximal ICA. The EDV (1.8 +/- 3.4 cm/s) was significantly lower than that in the control and AT groups. The ED ratio was greater than 1.4 in all cases. CONCLUSION: We conclude that B-mode scans and the EDV in the common carotid artery can help to distinguish between acute cardioembolic and atherothrombotic ICA occlusion.

Aged↗
PubMed1997

Evaluation of Triage screening for drugs of abuse in postmortem blood and urine samples.

A Triage screening system that utilizes a simple and rapid deproteinizing procedure using solid sulfosalicylic acid has been evaluated in 62 blood and 27 urine samples obtained from 72 consecutive autopsy cases. Among the blood samples, 11 were positive for amphetamines (AMP), 3 for barbiturates (BAR), and 1 for opiates (OPI). Of the 11 samples that were positive for AMP, only 1 contained methamphetamine (at a concentration of 1.37 micrograms/ml). All 10 samples that were falsely positive for AMP contained phenethylamine, a putrefactive amine, at concentrations of 0.83 to 2,070 micrograms/ml. Apparent negative reactions of the Triage system for benzodiazepines (BZO), AMP, BAR and tricyclic antidepressants (TCA) were observed in three, two one and one blood samples, respectively. These drugs were present in concentrations that were much lower than the lower detection limits of the device. Among the urine samples, nine were positive for AMP, three for BZO, three for BAR, two for OPI and one for TCA. Of the nine samples that were positive for AMP, only three contained methamphetamine (at concentrations of 7.95 to 44.9 micrograms/ml) and six contained no methamphetamine but did contain phenethylamine at concentrations of 0.52 to 14.3 micrograms/ml. False positive Triage reaction were observed only for AMP. There were no false negative Triage reactions from either the blood or urine samples examined for eight classes of drugs of abuse, namely phencyclidine (PCP), BZO, OPI, cocaine metabolites (COC), cannabinoids, AMP, BAR and TCA. The Triage screening system is not able to detect therapeutic or non-toxic levels of drugs of abuse in blood or to discriminate between AMP and putrefactive amines in moderately-to-heavily decomposed blood and urine samples. However, it may still be a useful tool in the field of forensic toxicology for the following reasons: 1) the deproteinizing method causes little reduction in the sensitivity of the Triage screening device to the drugs of abuse, even in turbid urine samples, and 2) it is able to detect toxic levels of PCP, BZO, COC, OPI and BAR in any kind of blood sample.

Amphetamine↗
PubMed1997

[The efficacy of postural drainage in a case of pulmonary edema following cholecystectomy].

An 81-year-old man underwent percutaneous transluminal gallbladder drainage. As the drain was accidentally removed six days later, he received cholecystectomy. After the operation, he developed hypotension, hypoxemia and ST level depression on ECG. He received artificial ventilation and cathecholamines. His chest CT showed marked pulmonary edema, and total protein of the edema-fluid was 3.3 g.dl-1. These findings suggested permeability pulmonary edema. He received postural drainage of the edema-fluid, and the pulmonary oxygenation was gradually improved. He was weaned from artificial ventilation on the 6th ICU day and discharged the next day.

Aged↗
PubMed1997

[Diagnosis of unruptured cerebral aneurysms using magnetic resonance angiography and three dimensional computed tomographic angiography].

The purpose of this study is to confirm the use of magnetic resonance (MR) angiography and three-dimensional computed tomographic (3D CT) angiography, in the screening of unruptured cerebral aneurysms. Sixty-six unruptured cerebral aneurysms in forty-eight patients were examined by MR angiography, 3D CT angiography and digital subtraction angiography (DSA). All cases underwent surgery. Three out of sixty-six (4.5%) cerebral aneurysms detected by MR angiography and 3D CT angiography were false positive. The false aneurysms were located at the region of the internal carotid artery and the posterior communicating artery, and were under 2.0mm in size. The diagnosis of the infundibular dilatation at the junction of the internal carotid artery and the posterior communicating artery remained difficult. The true positive diagnosis of aneurysms using MR angiography or 3D CT angiography was 95.5%, in our hospital. All unruptured cerebral aneurysms over 2.0mm in size were detected correctly by using MR angiography and 3D CT angiography, as well as DSA. The inadequate diagnosis of aneurysms caused by MR angiography was due to the overlapping of vessels and the surrounding noise. Superselective maximum intensity projection (MIP) and interactive vascular imaging (IVI) were adopted for exact diagnosis. Furthermore, the three slab method of MR angiography was used for containing the limits between the vertebral artery and the distal anterior cerebral artery, and the triple method was able to decrease surrounding noise. Using MR angiography, we diagnosed and operated on about 100 cases of unruptured cerebral aneurysm in one year. Our conclusion is that we can diagnose any unruptured cerebral aneurysm, over 2.0mm in size, using MR angiography and 3D CT angiography.

Adult↗
PubMed1997

[Cerebral embolism due to lone atrial septal aneurysm].

A 71-year-old man was admitted to our hospital because of headache and left hemiparesis. Brain CT scan showed hemorrhagic infarction of the right frontal lobe. Intravenous digital subtraction angiography revealed no occlusion of cerebral arteries. No arrhythmias were observed by the holter ECG. Transthoracic echocardiography showed no abnormalities. Anticoagulation therapy (heparin and warfarin) was started under the diagnosis of cerebral embolism without definite embolic source and there was no recurrence during following four years. Transesophageal echocardiography showed an atrial septal aneurysm (ASA) without patent foramen ovale. A potential cause of cerebral embolism due to atrial septal aneurysm is paradoxical embolization through an interatrial shunt (patent foramen ovale). It was speculated that ASA was a direct source of thrombus formation in this case (lone ASA). Transesophageal echocardiography should be performed to find atrial septal aneurysm in patients with cryptogenic stroke, especially embolic stroke without definite embolic sources.

Aged↗
PubMed1997

[Bilateral synchronous testicular seminomas: a case report and review of the Japanese literature].

A 39-year-old man was referred to our hospital with right testicular swelling. Ultrasonography and magnetic resonance imaging revealed bilateral, synchronous testicular tumors. Bilateral high inguinal orchiectomy was performed. Histological examination revealed anaplastic seminomas. Prophylactic radiation therapy was performed in the para-aortic and pelvic regions postoperatively, and no signs of metastasis have been found during the follow-up period of more than 5 months. Including the present case, 186 cases of bilateral testicular tumors reported in Japan are reviewed.

Adult↗
PubMed1997

[Analysis of pulmonary manifestations in patients with rheumatoid arthritis].

We studied chest X rays of 911 patients with rheumatoid arthritis (RA). The findings showed interstitial shadow in 28 patients (3.1%), pleuritis in 13 patients (1.4%) and nodular shadow in 3 patients (0.3%). RA patients with interstitial pneumonia were commonly male and older. And they had significantly high levels of rheumatoid factor (RF), RAPA and IgG-RF in serum, but they were not associated with high score of Lansbary index. All patients with more than 1500 IU/ml in RF value had a complication of interstitial pneumonia. These results suggest the importance of chest X-ray in the management of RA patients with high titer in RF.

Aged↗
PubMed1997

[The anesthetic management of patients in chronic renal failure for coronary artery bypass surgery without cardiopulmonary bypass].

We describe our experience with three patients in chronic renal failure who underwent coronary artery bypass surgery without cardiopulmonary bypass. Anesthesia was maintained with fentanyl and midazolam. Nitroglycerin and prostaglandin E1 were administered during the surgical procedure. When the coronary artery was clamped for the anastomosis of the graft, cardiac output and arterial pressure decreased in all cases. The patients were treated with ephedrine and dobutamine, which restored the hemodynamics. The important points for the anesthetic management for this operation are follows: the adequate administration of the coronary vasodilator, and attention to the change of hemodynamics on clamping the coronary artery.

Adult↗
PubMed1997

Intranuclear expression of cyclin D1 protein as a useful prognostic marker for mantle cell lymphoma.

Mantle cell lymphoma (MCL) has a characteristic chromosomal translocation, t(11:14) (q13;q32) involving rearrangement of bcl-1 locus, and the key oncogene of bcl-1 locus in PRAD1/cyclin D1 gene that encodes the protein regarding cell cycle. Recently, several studies using immunohistochemical and molecular methods have demonstrated the overexpression of cyclin D1 mRNA/protein in cases of MCL. We have studied immunohistochemical expression of cyclin D1 protein on frozen sections of 27 cases of MCLs and evaluated the relationship between the expression of cyclin D1 and prognosis. Sixteen (59.3%) cases showed intranuclear staining of cyclin D1 protein and 6 of 7 cases examined using RT-PCR methods showed the overexpression of PRAD1/cyclin D1 mRNA. The data indicate that intranuclear staining of cyclin D1 protein is associated with the overexpression of PRAD1/cyclin D1 mRNA. The survival time of cyclin-D1 positive group was shorter than that of cyclin D1-negative group, and there was a significant difference in survival time between the two groups (p < 0.05; log-rank test). These data suggest that the MCLs with overexpression of PRAD1/cyclin D1 protein has poor prognosis, and intranuclear expression of cyclin D1 protein is a useful prognostic marker for MCL.

Adult↗
PubMed1996

Purification and characterization of a (1-->3)-beta-D-glucan-binding protein from horseshoe crab (Tachypleus tridentatus) amoebocytes.

A novel (1-->3)-beta-D-glucan-binding protein (T-GBP) has been purified from the amoebocyte lysate of the Japanese horseshoe crab, Tachypleus tridentatus. It is a basic protein (pI 9.2) which appears to be a homotetramer composed of subunits with an apparent mol wt of 168000 and with an amino-terminal sequence (20 residues) KSGFILTAPKSLTLGRNNRL. T-GBP exerted an inhibitory effect on the (1-->3)-beta-D-glucan-initiated coagulation cascade reconstituted with purified preparations of factor G and the proclotting enzyme from the lysate. The binding of (1-->3)-beta-D-glucans to T-GBP was evaluated by measuring the residual amidolytic activity of the clotting enzyme, the product of the coagulation cascade, using Boc-Leu-Gly-Arg-4-nitroanilide as the chromogenic substrate. The binding specificity of a wide range of (1-->3)-beta-D-glucans and other polysaccharides towards T-GBP was expressed by the relative inhibition (%) of the activation of factor G, the first protease zymogen in the pathway, which is activated by binding to (1-->3)-beta-D-glucans. T-GBP was found to have a high affinity for linear (1-->3)-beta-D-glucans, e.g. pachyman, curdlan, and paramylon. It was able to bind to (1-->3)-beta-D-glucans with side-chain branches and mixed linkage such as schizophyllan, lentinan, laminarins, yeast beta-D-glucan, and (1-->3),(1-->4)-beta-D-glucans such as lichenin and barley beta-D-glucan. Binding of pachyman to T-GBP was demonstrated by an enzyme-linked immunosorbent assay using a specific antibody (rabbit IgG) raised against T-GBP.

Amino Acid Sequence↗
PubMed1996

Protein kinase C plays a key role in the cross-talk between intracellular signalings via prostanoid receptors in a megakaryoblastic cell line, MEG-01s.

In a previous study, we characterized prostanoid and thrombin receptors expressed on a megakaryoblastic cell line, MEG-01s (Blood 78, 2328-2336, 1991). In this study, we examines the mechanism of cross-talk between intracellular Ca2+ ([Ca2+]i) and cAMP signalings through prostanoid and thrombin receptors. Addition of a thromboxane (TX)A2 mimetic (U46619 or STA2) or thrombin stimulated the formation of inositol phosphates and dose-dependently augmented a prostaglandin (PG)I2 mimetic (iloprost)- or forskolin-induced cAMP formation. 12-O-tetradecanoylphorbol-13-acetate (TPA) and ionomycin, to lesser extent, also augmented iloprost-induced cAMP formation. The enhancing effect of U46619 or TPA on cAMP formation was inhibited by prolonged pretreatment of the cells with TPA (2.5 microM, 24 h), but not with calmodulin-antagonists; W-7, W-5, or KN-62. The elevation of [Ca2+]i induced by thrombin, STA2 or PGE2 was significantly suppressed by pretreatment of the cells with TPA (100 nM) as well as cAMP mimetics such as dibutyryl cAMP (5 mM), forskolin (5 microM) and iloprost (1 microM). These results suggest the key role of PKC on the cross-talk between [Ca2+]i and cAMP signalings through prostanoid and thrombin receptors; PKC, which is activated with TXA2 or thrombin, concomitantly suppress further [Ca2+]i elevation and enhances the PGI2 receptor-mediated cAMP formation, which, in turn, suppress [Ca2+]i elevation.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1996

Identification of genes differentially expressed in association with metastatic potential of K-1735 murine melanoma by messenger RNA differential display.

To identify genes differentially expressed in association with the metastatic potential of K-1735 mouse melanoma cells, the mRNA differential display method was applied to compare mRNAs from high- and low-metastatic K-1735-derived cells. Three of the high- and three of the low-metastatic clones were used to reduce the false positives in the initial screening, and Southern blot screening against reverse transcription-PCR products was used to confirm that cDNA fragments detect differential expression between high- and low-metastatic cells. By using 256 different combinations of modified long arbitrary primers which provide broad screening of expressed genes, approximately 12,000 cDNA fragments were amplified from mRNA of each cell line. Among them, eight genes were identified as being expressed in either high- or low-metastatic cells using Northern blot analysis. Integrin alpha6 and two unknown genes were expressed in high-metastatic cells, whereas beta-tropomyosin, macrophage colony-stimulating factor, inhibin/activin betaB subunit, and two unknown genes were expressed in low-metastatic cells. These results indicate that the acquisition of metastatic potential in tumor cells was regulated by activation and/or inactivation of several specific genes, such as those for cell adhesion molecule, cytoskeletal protein, and growth factors.

Animals↗
PubMed1996

Differential production of interleukin-6 and its close relation to liver metastasis in clones from murine P815 mastocytoma.

Interleukin-6 (IL-6)-producing abilities of plastic-adherent and plastic-non-adherent P815 clones were investigated in connection with the liver metastasis. Most adherent clones produced IL-6 at high level (over 10 ng/10(5) cells per 48 h), and they coincided with highly liver-metastatic clones. The remaining adherent and all the non-adherent clones tested produced IL-6 at low level (under 1.5 ng/10(5) cells), and they coincided with the low or non-liver-metastatic clones. The IL-6 production was greatly enhanced by IL-1 alpha, but not by IL-6, tumor necrosis factor-alpha or interferon-gamma.

Animals↗
PubMed1996

Cell type-/inducer-specific bidirectional regulation by thalidomide and phenylphthalimides of tumor necrosis factor-alpha production and its enantio-dependence.

Regulation by thalidomide and phenylphthalimide analogs (FPP-33 and PPS-33) of TNF-alpha production is specific to cell type and to inducer, i.e., (i) the compounds enhance TPA-induced TNF-alpha production by human leukemia HL-60 cells, while they inhibit TPA-induced TNF-alpha production by another human leukemia cell line, THP-1, and (ii) the compounds inhibit TNF-alpha production by both HL-60 and THP-1 cells when the cells are stimulated with okadaic acid (OA). The structure-activity relationships of these compounds are similar in the four assay systems (TPA/HL-60, TPA/THP-1, OA/HL-60, and OA/THP-1). However, optically active analogs, (S)- and (R)-alpha-methylthalidomides, show distinct bidirectional regulatory effects on TNF-alpha production, i.e., only the (S)-form shows TNF-alpha production-enhancing activity in the TPA/HL-60 assay system, while the (R)-form shows much more potent TNF-alpha production-inhibiting activity than the (S)-form in the other assay systems.

HL-60 Cells↗