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H Deguchi

Publications and source records attributed to H Deguchi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Plasma lipoproteins, hemostasis and thrombosis.

Regulation of hemostasis and thrombosis involves numerous plasma factors that contribute to procoagulant and anticoagulant pathways. Lipid-containing surfaces provide sites where both procoagulant and anticoagulant enzymes, cofactors and substrates are assembled to express their activities. Plasma and lipoproteins can contribute to either procoagulant or anticoagulant reactions. Procoagulant lipids/lipoproteins include triglyceride-rich particles in plasma and oxidized low density lipoprotein (LDL) which can accelerate activation of prothrombin, factor X and factor VII. Potentially anticoagulant lipids and lipoproteins, each of which enhances inactivation of factor Va by activated protein C, include phosphatidylethanolamine, cardiolipin, the neutral glycosphingolipids glucosylceramide and Gb3 ceramide (CD77), and high density lipoprotein (HDL). Remarkably, treatment of hyperlipidemia with statins not only lowers lipids but also provides antithrombotic effects whose mechanisms remain to be clarified. We hypothesize that procoagulant and anticoagulant lipids and lipoproteins in plasma may contribute to a Yin-Yang balance that helps influence the up-regulation and down-regulation of thrombin generation.

Animals↗
PubMed2000

Evaluation of viral infection in the myocardium of patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: The aim of this study was to evaluate the viral etiology of idiopathic dilated cardiomyopathy (DCM). BACKGROUND: The demonstration of enteroviral genome in hearts with DCM has reinforced the importance of enteroviruses in the pathogenesis of DCM. However, there is uncertainty about the character and activity of enteroviruses detected in the myocardium. Recently, the association of hepatitis C virus or adenovirus with DCM has been reported. METHODS: Myocardial specimens from 26 patients with idiopathic DCM, which were obtained at partial left ventriculectomy (PLV), were examined virologically. Strand-specific detection of enteroviral RNA was performed to differentiate active viral replication from latent persistence. Polymerase chain reaction was used to detect genomic sequences of hepatitis C virus, adenovirus, cytomegalovirus, influenza viruses, mumps virus, herpes simplex viruses, varicella-zoster virus and Epstein-Barr virus. RESULTS: Plus-strand enteroviral RNA was detected in 9 (35%) of the 26 patients. Minus-strand enteroviral RNA was determined in seven (78%) of these nine plus-strand RNA-positive patients. Sequence analysis revealed that the enteroviruses detected were coxsackie B viruses, such as coxsackievirus B3 and B4. However, genetic material from other viruses was not detected. Six (86%) of seven minus-strand enteroviral RNA-positive patients died of cardiac insufficiency within the first six months after PLV. CONCLUSIONS: Coxsackie B viruses were seen in hearts with idiopathic DCM. Active viral RNA replication appeared to be present in a significant proportion of these cases. Minus-strand coxsackieviral RNA in the myocardium can be a marker for poor clinical outcome after PLV. There was no evidence of persistent infection by other viruses in hearts with DCM.

Adolescent↗
PubMed2000

Cardiolipin is a normal component of human plasma lipoproteins.

Anticardiolipin (anti-CL) antibodies, diagnostic for antiphospholipid antibody syndrome, are associated with increased risks of venous and arterial thrombosis. Because CL selectively enhances activated protein C/protein S-dependent anticoagulant activities in purified systems and because CL is not known to be a normal plasma component, we searched for CL in plasma. Plasma lipid extracts [chloroform/methanol (2:1, vol/vol)] were subjected to analyses by using TLC, analytical HPLC, and MS. A plasma lipid component was purified that was indistinguishable from reference CL (M:1448). When CL in 40 fasting plasma lipid extracts (20 males, 20 females) was quantitated by using HPLC, CL (mean +/- SD) was 14.9 +/- 3.7 microgram/ml (range 9.1 to 24.2) and CL was not correlated with phosphatidylserine (3.8 +/- 1.7 microgram/ml), phosphatidylethanolamine (64 +/- 20 microgram/ml), or choline-containing phospholipid (1,580 +/- 280 microgram/ml). Based on studies of fasting blood donors, CL (>/=94%) was recovered in very low density, low density, and high density lipoproteins (11 +/- 5.3%, 67 +/- 11.0%, and 17 +/- 10%, respectively), showing that the majority of plasma CL (67%) is in low density lipoprotein. Analysis of relative phospholipid contents of lipoproteins indicated that high density lipoprotein is selectively enriched in CL and phosphatidylethanolamine. These results shows that CL is a normal plasma component and suggest that the epitopes of antiphospholipid antibodies could include CL or oxidized CL in lipoproteins or in complexes with plasma proteins (e. g., beta(2)-glycoprotein I, prothrombin, protein C, or protein S) or with platelet or endothelial surface proteins.

Antibodies, Antiphospholipid↗
PubMed2000

Increased plasma levels of tissue factor pathway inhibitor-activated factor X complex in patients with disseminated intravascular coagulation.

Plasma levels of tissue factor pathway inhibitor (TFPI)-activated factor Xa (FXa) complex were measured in patients with disseminated intravascular coagulation (DIC), pre-DIC, and DIC. Plasma levels of plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (SFM) were significantly higher in patients with DIC than in those with pre-DIC or non-DIC; the levels of these hemostatic markers were significantly higher in patients with pre-DIC than in those with non-DIC. Plasma levels of thrombin-antithrombin complex (TAT) were significantly higher in patients with DIC or pre-DIC than in those with non-DIC. Plasma levels of tissue factor (TF), total TFPI, free TFPI, and TFPI-Xa complex were significantly higher in patients with DIC than in those with non-DIC. Plasma levels of TFPI-Xa complex were significantly increased in patients with pre-DIC as compared to those with non-DIC; however, plasma free TFPI levels were significantly decreased in patients with pre-DIC as compared to those with non-DIC. These findings suggest that free TFPI might be consumed in the pre-DIC state, thereby confirming the activation of the extrinsic pathway. Plasma levels of TFPI-Xa complex were significantly correlated with TF, free TFPI, and total TFPI. Increased plasma TFPI-Xa complex levels might be useful for the diagnosis of DIC or pre-DIC, particularly that occurring by activation of the extrinsic pathway of blood coagulation.

Anticoagulants↗
PubMed2000

Refolding of firefly luciferase immobilized on agarose beads.

The renaturation yield of the denatured firefly luciferase decreased strongly with increasing protein concentration in a renaturation buffer, because of aggregation. In this study, firefly luciferase was immobilized on agarose beads at a high concentration. Although the protein concentration was extremely high (about 100-fold) compared to that of soluble luciferase, the renaturation yield was comparable with that for the soluble one. Thus, immobilization was shown to be effective for avoiding aggregation of firefly luciferase. It was also shown that the optimum buffer conditions for renaturation of the immobilized luciferase were the same as those for the renaturation in solution. Also, it was indicated that electrostatic interactions between a protein and the matrix have a negative effect on renaturation of the immobilized luciferase since the renaturation yield decreased at acidic pH only for the immobilized luciferase. These novel observations are described in detail in this paper.

Animals↗
PubMed2000

Causes of thrombophilia yet to be discovered: a personal view.

Prediction of genetic risk factors for venous thrombosis might best be left for only wise soothsayers. Nonetheless, based on the principle that hypercoagulability, either systemic or vascular-bed-specific, predisposes to thrombosis, we venture some speculations. Hyperactivity of platelets could be caused by elevated numbers of surface glycoproteins or defective signal transduction pathways. The reported efficacy of aspirin for prevention of venous thrombosis is consistent with the prediction that certain platelet defects may increase the risk of venous thrombosis. Hyperlipidaemia is associated with hypercoagulability, and lipoproteins exhibit procoagulant (e.g. triglyceride-rich particles and oxidized low-density lipoprotein) or anticoagulant (e.g. high-density-lipoprotein's cofactor activity for activated protein C/protein S) activities. This leads to the prediction that defects in lipids and/or lipoproteins may increase the risk for venous thrombosis. Interestingly, statins were recently reported to prevent the occurrence of venous thrombosis in the HERS (Heart and Estrogen/Progestin Replacement) trial. We also predict that new defects in the protein C pathway (e.g. defective endothelial protein C receptor or novel cofactors for activated protein C/protein S) will be discovered. Risk factors affecting the majority of patients will likely involve new single nucleotide polymorphisms (SNPs) like the factor V nt G1691A or prothrombin nt G20210A SNPs. The Human Genome Project will soon accelerate discovery of new SNPs that are risk factors for venous thrombosis.

Activated Protein C Resistance↗
PubMed2000

Hemostatic abnormalities in patients with thrombotic complications on maintenance hemodialysis.

Before hemodialysis (HD), plasma levels of tissue factor (TF), free-TF pathway inhibitor (TFPI) and thrombomodulin (TM) were significantly higher in patients with HD than in healthy volunteers. Plasma levels of (T-F) TFPI and plasmin plasmin inhibitor complex (PPIC) were significantly higher in patients with HD than in healthy volunteers. During HD, plasma levels of TF and (T-F) TFPI were not significantly increased, but plasma levels of total TFPI and free TFPI at 1 hour after and at the end of HD were significantly increased, compared with levels before start of HD. Plasma level of PPIC 1 hour after start of HD was significantly higher than before start of HD, and plasma levels of thrombin antithrombin complex (TAT), PPIC, D-dimer, TM, and protein C (PC) at the end of HD were significantly higher than before start of HD. In patients with thrombosis complications, plasma TF levels were significantly higher than in patients without thrombotic complications during HD. Plasma levels of PC were significantly lower in patients with thrombotic complications than in patients without thrombotic complications. There was no significant difference between both groups during HD in hemostatic parameters, with the exception of TF and PC. Hemostatic abnormalities existed in patients with HD; especially, increased TF and decreased PC might cause thrombotic complications.

Antifibrinolytic Agents↗
PubMed1999

Increased truncated form of plasma tissue factor pathway inhibitor levels in patients with disseminated intravascular coagulation.

To evaluate that the relationship between the truncated form of tissue factor pathway inhibitor (TFPI) and the stage of disseminated intravascular coagulation (DIC), we measured the plasma levels of tissue factor (TF) antigen and the intact and truncated forms of TFPI antigens in 41 patients with DIC, 12 with pre-DIC, and 20 with non-DIC. The plasma TF and total TFPI antigen levels were significantly higher in patients with DIC than in non-DIC patients. Plasma levels of intact TFPI antigen in the pre-DIC groups were significantly lower than in the non-DIC and DIC groups. The truncated form of TFPI antigen levels in DIC patients were significantly increased compared with those in non-DIC and pre-DIC patients. The fact that the intact form of TFPI was decreased in pre-DIC patients compared with that in non-DIC patients, suggests that it is consumed in the pre-DIC state and that hypercoagulability occurs in pre-DIC patients. The increased level of the truncated form of TFPI in DIC patients may be attributed to proteolysis of the intact form of TFPI in these patients. The increased level of the truncated form of TFPI may be a useful index for the diagnosis of DIC.

Disseminated Intravascular Coagulation↗
PubMed1999

A case of interleukin-6-producing malignant fibrous histiocytoma originating in the heart.

Primary cardiac malignant fibrous histiocytoma is extremely rare and its pathophysiological characteristics remain largely unknown. We treated a female patient with persistent fever and disseminated intravascular coagulation. Since ultrasonic echocardiography revealed the presence of a cardiac tumor and her serum interleukin-6 level was elevated, we speculated she had a cardiac myxoma. Histological examination of the surgically resected specimen, however, revealed that the tumor was malignant fibrous histiocytoma. Although her disseminated intravascular coagulation and heart failure were transiently improved after operation, local recurrence and systemic metastasis occurred and she died 7 weeks after operation. Using the autopsied specimen, we examined whether the malignant fibrous histiocytoma constitutively synthesized interleukin-6. The interleukin-6 content in the tumor was high, consistent with interleukin-6 production by the tumor. This was confirmed by immunohistochemical analysis. To our knowledge, this is the first report demonstrating interleukin-6 production by a cardiac malignant fibrous histiocytoma.

Aged↗
PubMed1999

[Trans-sternal bilateral thoracotomy for bilateral metastatic lung tumors].

Trans-sternal bilateral thoracotomy has been performed in 4 patients with bilateral metastatic lung tumors. The primary lesion was rectum in one case and the colon in three cases. Two patients were male and 2 were female. Their ages ranged from 63 to 78 years old. An inframammary incision was made with the patient in the supine position, and the chest was entered via the 4th or 5th intercostal space. This procedure provided excellent exposure of the entire mediastinum. Postoperative pain was comparatively severe in the early postoperative period, but was controlled by administering an epidural block. This procedure allows good exposure of the entire thoracic space through a single operative field. We conclude that trans-sternal bilateral thoracotomy is an excellent approach in the patient with bilateral metastatic lung tumors.

Aged↗
PubMed1998

Adenosine regulates tissue factor expression on endothelial cells.

The aim of this study was to evaluate the inhibitory activity of adenosine on tumor necrosis factor-alpha (TNF), thrombin-, or phorbol 12-myristate 13-acetate (PMA)-induced tissue factor (TF) expression on human umbilical vein endothelial cells (HUVECs). This inhibitory effect of adenosine was found to be counteracted by the non-selective adenosine receptor (AR) antagonist, 8-(p-sulfophenyl) theophylline. To clarify the role of ARs (A1, A2a, A2b, and A3) in this regulation, we evaluated the effect of several agonists and antagonists specific for AR-subclass on TF expression. The selective A2aAR agonist, 2-p-(2-carboxyethyl) phenethylamino-5'-N-ethylcarboxamido adenosine hydrochloride (CGS 21680), the A3AR agonist, N6-2-(4-aminophenyl) ethyladenosine (APNEA), and the A1AR antagonist, 1,3-dipropyl-8-(2-amino-4-chlorophenyl) xanthine (PACPX) each inhibited TF activity expression induced by TNF, thrombin, or PMA on HUVECs. In contrast, the selective A1AR agonist, chloro-N6-cyclopentyladenosine (CCPA) and the A2AR antagonist, 3,7-dimethyl-1-propargylxanthine (DMPX) enhanced each stimulant-induced TF activity expression. All agonist or antagonist alone did not alter the basal TF expression on HUVECs. Our results suggest that stimulation of A2aAR and A3AR down-regulates and that of A1AR up-regulates the endothelial cell TF expression induced by TNF, PMA, or thrombin. Thus, it appears that adenosine itself may exert anticoagulant activity on vascular endothelial cells via its A2a and A3 receptors, particularly during ischemic or atherosclerotic processes which are known to be associated with local increased levels of adenosine.

Adenosine↗
PubMed1998

Collagen subtypes and matrix metalloproteinase in idiopathic restrictive cardiomyopathy.

BACKGROUND: Idiopathic restrictive cardiomyopathy is a rare disease characterized by diastolic dysfunction, and the pathogenesis of the stiff heart remains unclear. The purpose of this study was to analyze the subpopulation of collagen fibers and determine the expression of matrix metalloproteinase in restrictive cardiomyopathy. METHODS AND RESULTS: In endomyocardial biopsy specimens obtained from seven patients with restrictive cardiomyopathy, collagen fiber types I, III, and IV, and matrix metalloproteinase- and two were observed by light and electron microscopy, using monoclonal antibodies. Type I collagen was less prominent in the interstitium, whereas the immunoreactivity for type III collagen was marked. The immunoreactivity against matrix metalloproteinase-1 was observed along with types I and III collagen fibers and in the cytoplasm of some fibrocytes/fibroblasts. The matrix metalloproteinase-1 tended to increase when the reactivity against types I and III collagen was prominent. Both type IV collagen and matrix metalloproteinase-2 were observed along arterial walls and the basement membrane of cardiocytes. CONCLUSIONS: Increased type III collagen may play an important role as the cause of left ventricular stiffness in restrictive cardiomyopathy. The matrix metalloproteinase appeared to be involved in a cascade of collagen synthesis and the remodeling of the heart in patients with restrictive cardiomyopathy.

Adult↗
PubMed1998

Spontaneous myocarditis in DBA/2 mice. Light microscopic study with transmission and X-ray analytical electron microscopic studies.

DBA/2 inbred mice spontaneously develop myocarditis and a unique form of subepicardial inflammation of the right ventricle characterized by a prominent eosinophilic infiltrate with calcinosis. We studied this myocarditis using light microscopy and both transmission and analytical X-ray electron microscopy, paying particular attention to eosinophil-associated cardiocyte injury. At 5 weeks of age, many eosinophils and mononuclear cells (MNCs) were seen in the subepicardium of the right ventricle. Electron microscopy showed that cardiocytes underwent degenerative changes, including myofibrillar lysis, accumulation of Z-band material and mitochondrial inclusions, and rupture of plasma membranes. The infiltrating eosinophils appeared to be activated, and cells with cytoplasmic vacuoles, suggestive of degranulation, were noted. The myocardial injury was most severe in the 7th week and healed with myocardial fibrosis and calcinosis by the 8th week. Analytical X-ray electron microscopy showed that the calcinosis was initiated in mitochondrial inclusions of injured cardiocytes. The peripheral eosinophil count did not increase during the course of the disease, but there was a positive correlation between the ratio of eosinophils to infiltrated white blood cells (Eo/WBCs) in the right ventricle and the severity of myocardial damage. Eosinophils may play a significant part in subepicardial cardiocyte injury seen in DBA/2 mice.

Animals↗
PubMed1998

Prevalence of childhood and adolescent atopic dermatitis in a Japanese population: comparison with the disease frequency examined 20 years ago.

To ascertain the prevalence of childhood and adolescent atopic dermatitis in a Japanese population, we clinically observed the total body of 5 to 6-year-old children (994 cases), 7 to 9-year-old children (1,240 cases), 10 to 12-year-old children (1,152 cases), 13 to 15-year-old children (1,670 cases), and 16 to 18-year-old adolescents (2,159 cases). The examination was performed in the spring of 1994-96, when exacerbation of childhood and adolescent atopic dermatitis most frequently occurs in Japan. Atopic dermatitis was observed in 24% of the 5 to 6-year group, in 19% of the 7 to 9-year group, in 15% of the 10 to 12-year group, in 14% of the 13 to 15-year group, and in 11% of the 16 to 18-year group. The prevalence of atopic dermatitis in 9 to 12-year-old children was two times and in 18-year-old adolescents five times as high as in similar age groups examined 20 years ago.

Adolescent↗
PubMed1998

Midterm results of thoracoscopic surgery for pulmonary metastases especially from colorectal cancers.

Indications for thoracoscopic metastatectomy remain controversial because not all metastatic tumors may be detected without the manual palpation that is possible with thoracotomy. However, the accuracy (92%) of preoperative lung imaging in patients with one or two lesions led us to re-evaluate thoracoscopic metastatectomy with patient survival as the primary end point. Thoracoscopic wedge resection using an endoscopic stapling device or video-assisted thoracic surgery (VATS) lobectomy was performed in patients with one or two pulmonary metastases. Thoracoscopic resection was performed in 27 patients with 22 solitary lesions and 5 patients with two lesions. The primary tumors were colorectal cancer (15), testicular cancer (3), osteosarcoma (2), and seven other histologies. In 5 of 27 patients (18.5%) a thoracoscopic operation was converted to a VATS procedure, which requires minithoracotomy to identify metastasis primary by digital palpation. The 3-year survival rate for colorectal cancer patients who underwent thoracoscopic resection was 56.4%, in comparison to 48.6% in historical control thoracotomy patients (n = 16). There was no statistically significant difference between the two groups. Thoracoscopic resection of one or two colorectal cancer lung metastases results in a survival rate similar to standard thoracotomy, and thereby provides an acceptable alternative to this more invasive approach.

Adolescent↗
PubMed1998

Ultraviolet light is an environmental factor aggravating facial lesions of adult atopic dermatitis.

An increasing number of adult patients with atopic dermatitis (AD) in Japan are distressed by persistent eczematous lesions of the face (so-called atopic red face). Phototests were carried out in 28 patients with the atopic red face to test a possibility that ultraviolet (UV) light could be an aggravating factor. Contact and photocontact dermatitis had been ruled out by repeated patch and photopatch tests. All of the patients had a normal response to a screening dose of UVA (10 J/sq cm) and a normal minimal erythema dose (MED) of UVB. Ten of these patients, however, showed an abnormal papular response to a single or 3-times consecutive UVB radiation above the MED (90 mJ/sq cm).

Adult↗