Search PubMed⌕ Search

Biomedical subjects

S Suzuki

Publications and source records attributed to S Suzuki.

At least 163 records · Page 9Linked to original sources

Lectin-histochemical and -cytochemical study of periodic acid Schiff-positive lysosome granules as a histological feature of the female mouse kidney.

Renal proximal straight tubules (PST) of the female mouse contain periodic acid Schiff-positive lysosome granules. An excellent example of this is found in the kidneys of female DBA/2Cr mice. In the present study, lectin-histochemistry showed that lectin-positive granules occur in the PST of DBA/2Cr mice. Out of twenty-one lectins studied, the granules bound WGA, s-WGA, LEL, STL, DSL, GSL-II, VVL, RCA-I, ECL, PSA, LCA and PHA-E. Such granules were also observed in the proximal convoluted tubules (PCT). In addition, heterogeneous binding to the SBA or DBA was observed in the PST. Lectin-cytochemistry for s-WGA, STL, VVL, RCA-I, ECL and PSA, showed that: 1) lysosomes bind a higher level of s-WGA or STL than VVL, RCA-I, ECL or PSA; 2) PSA binding is similar in PST and PCT; 3) there are many PCT lysosomes that are negative for s-WGA, STL, VVL, RCA-I, and ECL lectin binding; and 4) s-WGA binding is highly specific to the lysosomes of the PST. Based on the binding specificities of each lectin, it was suggested that the mannose content of PST and PCT lysosomes is similar, and that PST lysosomes have a high level of N-acetylglucosamine, N-acetylgalactosamine, galactose or galactosyl (beta 1, 4) N-acetylglucosamine.

Animals↗

Minimal change nephrotic syndrome, lymphadenopathy and hyperimmunoglobulinemia after immunization with a pneumococcal vaccine.

A 67-year-old female was admitted to our hospital with eruption and cervical lymphadenopathy which occurred one week after pneumococcal vaccination. Polyclonal hyperimmunoglobulinemia (IgG 6,620 mg/dl) and mild plasma cell proliferation (6.4%) in a bone marrow specimen were found, but a lymph node aspiration biopsy showed no specific findings. Normochromic and normocytic anemia with a positive direct Coombs test were also confirmed. Short-term intensive steroid therapy was given, but the systemic eruption and lymphadenopathy continued. About 4 months after vaccination, she suffered from edema in her face and legs and visual disturbance. When massive proteinuria (10.4 g/day) was found, she was admitted to our ward. A renal biopsy specimen showed a minor glomerular abnormality with mild interstitial plasmacytic infiltration. An abdominal CT scan showed hepatosplenomegaly and para-aortic lymphadenopathy. Uveitis was also found by ophthalmoscopy. These abnormalities completely disappeared after intensive steroid therapy including pulse therapy. On the basis of her clinical course and laboratory findings, it was suggested that minimal change nephrotic syndrome might be induced after vaccination, possibly due to hypersensitivity syndrome.

Aged↗

Myocardial protection of the pressure overload hypertrophied heart in human cardiac surgery by acceleration of anaerobic glycolysis.

BACKGROUND: Because of the decreased tolerance to ischemia and increased reperfusion injury in hypertrophied myocardium, myocardial hypertrophy is a well known risk factor for cardiac surgery. We have previously demonstrated in a left ventricular hypertrophy (LVH) model that a highly buffered cardioplegic solution (HBS) that provided glucose as a substrate and promoted anaerobic glycolysis during ischemia afforded superior myocardial protection when compared to standard formulations. And we reported the superiority of this cardioplegia in human cardiac surgery. METHODS: In this study, 16 patients with aortic stenosis (AS) and LVH receiving HBS were reviewed and compared to another patient group with AS and LVH who received either cold blood cardioplegia (CBC; n=5) or glucose insulin potassium (GIK; n=6). RESULTS: Postoperative cardiac index was better in the HBS group than the other two groups with similar or lower catecholamine. CK-MB was lower in HBS group than GIK group, but this was not significant. Only one DC cardioversion was required in the HBS group, whereas 2 DC in the CBC group and total 7 DC in the GIK group. CONCLUSIONS: We found that histidine buffered cardioplegic solution provided comparable or better pump performance after surgery with relatively lower inotropic requirement, less DC cardioversion and homologous blood requirements for left ventricular hypertrophied heart associated with aortic stenosis.

Aged↗

[A new formula to calculate perfusion rate in advanced hemodilution and tepid cardiopulmonary bypass].

BACKGROUND: During cardiopulmonary bypass, perfusion flow rate is generally calculated only with the patient body surface. Recently, far advanced hemodilution during cardiopulmonary bypass and tepid bypass circulation are common. PURPOSE: We have arrived at an appropriate flow rate formula, in which factors like temperature, hemoglobin concentration, the target mixed venous oxygen saturation (SvO2), and the amount of oxygen consumption are included. Our formula was compared with the conventional one. MATERIAL AND METHOD: Seventy-four points of cardiopulmonary bypass data under total cardiopulmonary bypass in 33 patients were studied. Our formula's validity was re-evaluated. Then, the SvO2 values were predicted by applying the flow rate value as per conventional calculation in to our formula. RESULTS: The flow rate of our formula and the actual flow rate are well correlated (r = 0.9212). In the prediction of the SvO2 by the conventional method, 36.5% were calculated to have a SvO2 of less than 60%. Furthermore, with a hemoglobin concentration of 7 g/dl, 73.3% were calculated to have a SvO2 of less than 60%. With a body temperature of 34 degrees centigrade, 53.8% were calculated to have a SvO2 of less than 60%. On the other hand, to maintain SvO2 level at 70% by the conventional method, if the patient hemoglobin concentration was 10 g/dl, temperature should be maintained at 36 degrees centigrade, and when hemoglobin concentration is 7 g/dl, the temperature should be maintained at 33 degrees centigrade. CONCLUSION: In advanced hemodilution or tepid cardiopulmonary bypass, use of appropriate flow rate formula is recommended, which takes into account the indispensable factors such as hemoglobin levels, temperature, and the target SvO2.

Adolescent↗

[Surgical management of acute type A aortic dissection with a complaint of disturbance of consciousness; report of a case].

A 50-year-old female was admitted to our hospital with a chief complaint of disturbance of consciousness (DOC). Left-sided hemiparalysis was noted on examination and cerebral infarction was diagnosed with total occlusion of the right common carotid artery revealed by cerebral angiography. Pharmacological thrombolysis (urokinase 720,000 U) was performed. Dissection of the right common carotid artery was noted after successful thrombolytic therapy. Enhanced chest computed tomography (CT) showed the acute type A aortic dissection involving the cerebral artery. Ascending aortic replacement was performed 4 days after the thrombolytic therapy to avoid brain edema and hemorrhagic infarction during cardiopulmonary bypass. The postoperative course was uneventful. In the case of acute type A aortic dissection with DOC, proper indication and optimal timing of the operation may help to improve patient survival.

Acute Disease↗

Up-regulation of the Ire1-mediated signaling molecule, Bip, in ischemic rat brain.

The endoplasmic reticulum (ER) is thought to play important roles in various neurological diseases via multifactorial and complex mechanisms. The Ire1-mediated signal is part of one ER signaling pathways; the signal induces the expression of an ER-resident protein, Bip/GRP78, and is thought to be involved in cell death under ER stress. In this study, we examined time-dependent Bip expression after transient middle cerebral artery occlusion and characterized the Bip-positive cells. Ire1- mediated molecules, Bip, were rapidly up-regulated in the ischemic area after 3.5 h recirculation. Their immunoreactivity continued to increase until 24-48 h. Immunofluorescence staining revealed Bip up-regulation in ischemic neurons, which were TUNEL positive. Our studies suggest that the Ire1-mediated signal might be associated with ischemic neuronal damage.

Animals↗

Development of an artificial dermis preparation capable of silver sulfadiazine release.

This article describes the antibacterial effects of an artificial dermis impregnated with silver sulfadiazine (Ag-SD) in vitro as well as in vivo. In the in vitro test, silver release from the artificial dermis impregnated with Ag-SD, by immersion in collagenase solution was controlled by the degradation of the collagen sponge. The artificial dermis impregnated with 3% or higher doses of Ag-SD completely suppressed the growth of Pseudomonas aeruginosa (Ps.) or Staphylococcus aureus (St.). The cytotoxicity test revealed that impregnation of 5% or higher doses of Ag-SD suppressed the growth of fibroblasts. However, when the artificial dermis impregnated with Ag-SD was implanted into full-thickness skin defects on the backs of guinea pigs, no tissue damage was histologically observed around the implanted site of the dermis. In the in vivo test, the artificial dermis impregnated with 10% Ag-SD, which was grafted on experimentally contaminated wounds in the backs of guinea pigs, macroscopically suppressed degradation of the collagen sponge, and significantly reduced the growth of both Ps. and St., compared with artificial dermis without Ag-SD. We conclude that collagen sponge impregnated with Ag-SD is a promising artificial dermis applicable to treat contaminated wounds.

Animals↗

In situ gelling xyloglucan formulations for sustained release ocular delivery of pilocarpine hydrochloride.

Thermoreversible gels formed in situ by aqueous solutions of an enzyme-degraded xyloglucan polysaccharide were evaluated as sustained release vehicles for the ocular delivery of pilocarpine hydrochloride. In vitro release of pilocarpine from gels formed by warming xyloglucan sols (1.0, 1.5 and 2.0% w/w) to 34 degrees C followed root-time kinetics over a period of 6 h. The miotic responses in rabbit following administration of xyloglucan sols were compared with those from in situ gelling Pluronic F127 sols and from an aqueous buffer solution containing the same drug concentration. Sustained release of pilocarpine was observed with all gels, the duration of miotic response increasing with increase of xyloglucan concentration. The degree of enhancement of miotic response following sustained release of pilocarpine from the 1.5% w/w xyloglucan gel was similar to that from a 25% w/w Pluronic F127 gel.

Animals↗

Prepro-thyrotropin releasing hormone 178-199 immunoreactivity is altered in the hypothalamus of the Wistar-Kyoto strain of rat.

The rat prepro-thyrotropin releasing hormone (TRH) 178-199 is derived from prepro-TRH by the actions of the endopeptidases, prohormone convertase 1 (PC1) and PC2. PPTRH 178-199 attenuates the synthesis and secretion of adrenocorticotropic hormone (ACTH) from the anterior pituitary both in vitro and in vivo, suggesting an inhibitory action on hypothalamic-pituitary-adrenal (HPA) axis function. This peptide also acts centrally to increase activity and decrease anxiety related behaviors. To elucidate the involvement of this peptide in these functions, we have compared the expression of PPTRH 178-199, PPTRH mRNA, and PC1 and PC2 mRNAs in the Wistar-Kyoto (WKY) and Wistar strains of rat. WKY rats have been shown to possess neuroendocrine abnormalities (HPA hyper-activity) and hyper-emotional behavioral characteristics. Immunohistochemical analysis of PPTRH 178-199 demonstrated significant strain differences in the paraventricular nucleus (PVN) of the hypothalamus and the parastrial nucleus (PSN). WKY rats had significantly greater numbers of immunoreactive (IR) cell body profiles (P<0.0005) than Wistar rats in the PVN and a significantly lower fiber density (P<0.002) in the PSN. Levels of PPTRH, PC1, and PC2 mRNA were not different between strains in any brain region examined. These data suggest that altered levels of PPTRH 178-199 in WKY rats could cause, at least in part, the hyper-activity of the HPA axis and the hyper-emotional behavioral characteristics seen in this rat strain. Such data fit with the hypothesis that PPTRH 178-199 is involved in the regulation of the HPA axis and behavior.

Adrenocorticotropic Hormone↗

Changes of beta-actin mRNA expression in canine vasospastic basilar artery after experimental subarachnoid hemorrhage.

The aim of this study was to investigate whether vascular remodeling occurs during cerebral vasospasm after subarachnoid hemorrhage (SAH). Beta-actin mRNA expression and structural change of its 3' untranslated region (UTR) which are considered a non-specific marker for vascular remodeling, were examined by Northern analysis and polymerase chain reaction analysis in a canine basilar artery after experimental SAH. The changes in the area of tunica media in the basilar artery were also examined histopathologically. Increased beta-actin mRNA expression and its structural changes of 3' UTR in the vasospastic basilar artery were markedly seen 7 and 14 days after SAH accompanied by increased area of tunica media in the basilar artery. The results suggest that vascular remodeling occurs and takes part in the luminal narrowing during cerebral vasospasm.

3' Untranslated Regions↗

Monitoring of phthalic acid monoesters in river water by solid-phase extraction and GC-MS determination.

An analytical method for monitoring 10 phthalic acid monoesters in river water was investigated by solid-phase extraction, methylation with diazomethane, and GC-MS. Two cartridge-type solid phases packed with octadesyl-coated silica (C18) and styrenedivinyl polymer (PS-2) and one disk-type solid phase made from octadesyl-coated styrenedivinylbenzene polymer (SDB-XD) were investigated in solid-phase extraction. PS-2 gave the highest recoveries of the three solid phases, and recoveries of more than 80% of the monoesters in filtered water samples were obtained at pH 2 to 3 with PS-2 at the spiked level of 0.1 microg L(-1), except for monomethyl-phthalate (MMP), in which more than 72% of the monoesters were recovered. For the monoesters in the suspended solids (SS), an acidic methanol extract of SS was added to purified water acidified to pH 2, and the monoesters were extracted with PS-2. The recoveries of the monoesters in SS were more than 80%, but the recoveries of MMP were more than 57%. The method detection limit (MDL) of each phthalic acid monoester in 500 mL of water sample and in 2 mg of dry weight of SS ranged from 0.010 to 0.030 microg L(-1) and from 1 to 11 microg g(-1), respectively. Monitoring of phthalic acid monoesters in the Tama River in Tokyo was conducted every month from March 1999 to February 2000 using the present method. MMP, mono-n-butyl-phthalate (MBP), and mono-(2-ethylhexyl)-phthalate (MEHP) were detected at concentrations of 0.030-0.0340, 0.010-0.480, and 0.010-1.30 microg L(-1), respectively, in the filtered water samples but were not detected in SS. Dimethyl-phthalate (DMP), di-n-butyl-phthalate (DBP), and di-(2-ethylhexyl)-phthalate (DEHP) were detected in the river water at concentrations of 0.010-0.092, 0.008-0.540, and 0.013-3.60 microg L(-1), respectively. Diethyl-, di-iso-butyl-, and benzylbutyl-phthalates were also detected at concentrations of nanograms per liter, whereas the corresponding monoesters did not appear. The concentrations of MBP and MEHP in the river water were slightly lower than those of the corresponding diesters at the majority of sampling sites and sampling times.

Chemistry Techniques, Analytical↗

Infectivity of aquabirnavirus strains to various marine fish species.

To determine the infectivity of marine birnavirus (MABV) in various marine fish species, experimental infection was performed in combination groups of 5 fish species with 7 strains of MABV and 1 strain of infectious pancreatic necrosis virus (IPNV). Mortality was observed in yellowtail Seriola quinqueradiata and amberjack S. dumerili infected with MABV strains Y-6, Y-10K and H-1, but not in other infected species. MABV was reisolated from most combination groups, but the virus isolation rate and virus infectivity titer were often significantly different among groups with the same fish species or with the same virus strain. All MABV strains replicated well in makogarei Limanda yokohamae, but only slightly in tiger puffer Takifugu rubiipes. IPNV also replicated in all fish species without causing death. The isolation rate and infectivity titer of IPNV were similar to or higher than those of non-virulent strains of MABV. In conclusion, the infectivity of MABV for different fish species is considered to change, which is an important factor in the development of the infection cycle of this virus among marine organisms.

Animals↗

Splenomegaly induced by recombinant human granulocyte-colony stimulating factor in rats.

Spontaneous ruptures of the spleen have been observed in donors and patients with malignancy during mobilization of peripheral blood stem cells. Thus, we investigated the morphological and histological alteration of the spleen, and mRNA expression levels and activities of the DNA-synthesizing enzymes thymidylate synthase (TS) and thymidine kinase (TK) in the splenic cells, of rats treated with recombinant human granulocyte-colony stimulating factor (rhG-CSF). Daily injections of rhG-CSF for 5 or 7 days slightly enhanced the splenic weight. Single or 3-day treatment with rhG-CSF markedly enhanced the number of granulocytes in peripheral blood. Expression levels of TS and TK mRNA in the splenic cells were significantly increased 6 hours after rhG-CSF treatment. Early expression of TS and TK mRNA in the splenic cells may indicate a reseeding of hematopoietic cells from the bone marrow. Daily injections with rhG-CSF enhanced the TS and TK activities in the splenic cells. As continuous elevations of DNA-synthesizing enzyme activity and spleno-megaly are suggestive of a possible splenic rupture, the monitoring of peripheral granulocytes and splenic size is necessary during the rhG-CSF treatment.

Animals↗

Heterogeneous immunogenetic background in Japanese adults with myasthenia gravis.

The aim of this study was to elucidate the roles of human leukocyte antigen (HLA) class II genes in disease susceptibility in Japanese adult patients with myasthenia gravis (MG). A number of studies have shown that MG is correlated with DR3 in Caucasians. In Japanese, infantile MG is associated with DR9, but the HLA class II alleles associated with adult MG remains unclear. HLA-DRB1 and DQB1 alleles were determined by genotyping in 75 Japanese adult patients with MG and in 115 race-matched healthy adults. No statistically significant difference was observed in the overall prevalences of DRB1 and DQB1 alleles between MG patients and healthy controls, even when the patients and controls were stratified on the basis of their gender. MG patients with DQB1*0604 were younger and those with DQB1*0402 were older at disease onset than those without (P=0.03 and 0.008, respectively). Concomitant autoimmune thyroid disease was associated with DRB1*0803 (P=0.0009, corrected P=0.04). In addition, anti-acetylcholine receptor antibody levels were significantly higher in patients with DQB1*0604 than in those without (P=0.045). These findings indicate that immunogenetic backgrounds in Japanese adult MG patients are heterogeneous and are apparently different from those in Caucasian patients.

Adult↗

Sterol regulatory element-binding proteins induce an entire pathway of cholesterol synthesis.

To evaluate the effects of sterol regulatory element-binding proteins (SREBPs) on the expression of the individual enzymes in the cholesterol synthetic pathway, we examined expression of these genes in the livers from wild-type and transgenic mice overexpressing nuclear SREBP-1a or -2. As estimated by a Northern blot analysis, overexpression of nuclear SREBP-1a or -2 caused marked increases in mRNA levels of the whole battery of cholesterogenic genes. This SREBP activation covers not only rate-limiting enzymes such as HMG CoA synthase and reductase that have been well established as SREBP targets, but also all the enzyme genes in the cholesterol synthetic pathway tested here. The activated genes include mevalonate kinase, mevalonate pyrophosphate decarboxylase, isopentenyl phosphate isomerase, geranylgeranyl pyrophosphate synthase, farnesyl pyrophosphate synthase, squalene synthase, squalene epoxidase, lanosterol synthase, lanosterol demethylase, and 7-dehydro-cholesterol reductase. These results demonstrate that SREBPs activate every step of cholesterol synthetic pathway, contributing to an efficient cholesterol synthesis.

Animals↗

Broad distribution of the JC virus receptor contrasts with a marked cellular restriction of virus replication.

To investigate the early events of JC virus (JCV) infection, including attachment, penetration, transport to the nuclei, and replication of the virus, we analyzed the susceptibility of 15 different cell lines to infection using a semiquantitative polymerase chain reaction (PCR) assay, in situ hybridization, laser scanning confocal microscopy, and a viral replication assay. The cell lines examined were human permissive and nonpermissive cells as well as cells of monkey and mouse origin. JCV entry into the nuclei of the all cell lines was observed within 10 min after inoculation, demonstrating that the virus receptor is widely distributed among mammalian cells. Inhibition of viral entry by an anti-JCV VP1 antibody and sialidase treatment to remove sialic acid residues, which are considered a candidate for the JCV receptor, suggested that VP1 may interact with the cellular surface sialic acid. In addition, chlorpromazine, a clathrin-dependent pathway inhibitor, significantly suppressed entry of JCV into nuclei. In spite of the broad spectrum of cells susceptible to JCV entry, replication of the virus occurred exclusively in human neuroblastoma cell lines. These results suggest that whereas JCV can enter a wide variety of cell types and localize to the nuclei, cell-specific intranuclear mechanisms are required for virus replication.

HeLa Cells↗

Activation of NG2-positive oligodendrocyte progenitor cells during post-ischemic reperfusion in the rat brain.

This study examines the alteration of oligodendrocyte progenitor cells which express membrane NG2 chondroitin sulfate proteoglycan after focal ischemia in the rat brain. Adult male Sprague-Dawley rats were subjected to 90 min occlusion of the middle cerebral artery, followed by reperfusion time of up to 2 weeks. The distribution and morphological changes in NG2-positive oligodendrocyte progenitor cells were immunohistochemically examined. Stellate-shaped NG2-positive cells with multiple branched processes were detected in both the gray and white matter of normal brain. After 2 weeks of reperfusion, NG2-positive cells in the area surrounding the infarction site (peri-infarct area) clearly showed enlarged cell bodies with hypertrophied processes. These stained strongly for NG2. Although the number of NG2-positive cells was increased significantly in the peri-infarct area, it decreased markedly in the infarct core compared to controls. Double immunostaining revealed that these NG2-positive cells were neither astrocytes nor microglia, but NG2-positive oligodendrocyte progenitor cells. These progenitor cells are known to differentiate into oligodendrocytes. As such, this upregulation of NG2 expression may be an adaptive mechanism attempting to remyelinate rat brain tissue after ischemic insult. Only further study will elucidate this hypothesis.

Animals↗