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1.
Phys Chem Chem Phys ; 25(9): 6684-6692, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36806473

RESUMO

We have combined the extended X-ray absorption fine structure (EXAFS) and X-ray emission spectroscopy (XES) to investigate the local structure and the local iron magnetic moments of (Li1-xFex)OHFeSe (x∼0.2) superconductors. The local structure, studied by Fe K-edge EXAFS measurements, is found to be inhomogeneous that is characterized by different Fe-Se bond lengths. The inhomogeneous phase exhibits a peculiar temperature dependence with lattice anomalies in the local structural parameters at the critical temperature Tc (36 K) and at the spin density wave (SDW) transition temperature TN (130 K). Fe Kß XES shows iron to be in a low spin state with the local Fe magnetic moment evolving anomalously as a function of temperature. Apart from a quantitative measurement of the local structure of (Li1-xFex)OHFeSe, providing direct evidence of nanoscale inhomogeneity, the results provide further evidence of the vital role that the coupled electronic, lattice and magnetic degrees of freedom play in the iron-based superconductors.

2.
Phys Chem Chem Phys ; 22(39): 22217-22225, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32996510

RESUMO

We have studied the local structure of layered Eu(La,Ce)FBiS2 compounds by Bi L3-edge extended X-ray absorption fine structure (EXAFS) measurements as a function of temperature. We find that the BiS2 sub-lattice is largely distorted in EuFBiS2, characterized by two different in-plane Bi-S1 distances. The distortion is marginally affected by partial substitutions of Ce (Eu0.5Ce0.5FBiS2) and La (Eu0.5La0.5FBiS2). The temperature dependence of the local structure distortion reveals an indication of possible charge density wave like instability in the pristine self-doped EuFBiS2 and Ce substituted Eu0.5Ce0.5FBiS2 while it is suppressed in La substituted Eu0.5La0.5FBiS2. In compounds with higher superconducting transition temperature, the axial Bi-S2 bond distance is elongated and the related bond stiffness decreased, suggesting some important role of this in the charge transfer mechanism for self-doping in the active BiS2-layer. In-plane Bi-S1 distances are generally softer than the axial Bi-S2 distance and they suffer further softening by the substitutions. The results are discussed in relation to an important role of the Bi defect chemistry driven asymmetric local environment in the physical properties of these materials.

3.
Nano Lett ; 19(9): 5915-5919, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373825

RESUMO

Diamond has two crystallographically inequivalent sites in the unit cell. In doped diamond, dopant occupation in the two sites is expected to be equal. Nevertheless, preferential dopant occupation during growth under nonequilibrium conditions is of fundamental importance, for example, to enhance the properties of nitrogen-vacancy (N-V) centers; therefore, this is a promising candidate for a qubit. However, the lack of suitable experimental techniques has made it difficult to study the crystal- and chemical-site-resolved local structures of dopants. Here, we confirm the identity of two chemical sites with asymmetric dopant incorporation in the diamond structure, via the photoelectron holography (PEH) of heavily phosphorus (P)-doped diamond prepared by chemical vapor deposition. One is substitutionally incorporated P with preferential site occupations and the other can be attributed to a PV split vacancy complex with preferential orientation. The present study shows that PEH is a valuable technique to study the local structures around dopants with a resolution of crystallographically inequivalent but energetically equivalent sites/orientations. Such information provides strategies to improve the properties of dopant related-complexes in which alignment is crucial for sensing of magnetic field or quantum spin register using N-V centers in diamond.

4.
Sci Technol Adv Mater ; 15(5): 055007, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27877719

RESUMO

The transport and magnetic properties of the tetragonal Fe[Formula: see text]S were investigated using magnetoresistivity and magnetization within [Formula: see text] K, [Formula: see text] 70 kOe and [Formula: see text] 3.0 GPa. In addition, room-temperature x-ray diffraction and photoelectron spectroscopy were also applied. In contrast to previously reported nonmetallic character, Fe[Formula: see text]S is intrinsically metallic but due to a presence of a weak localization such metallic character is not exhibited below room temperature. An applied pressure reduces strongly this additional resistive contribution and as such enhances the temperature range of the metallic character which, for ∼3 GPa, is evident down to 75 K. The absence of superconductivity as well as the mechanism behind the weak localization will be discussed.

5.
J Nutr Health Aging ; 25(5): 593-599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33949624

RESUMO

BACKGROUND/OBJECTIVES: Depression and hopelessness are frequently experienced in chronic kidney disease (CKD) and are generally associated with lessened physical activity. The aim of this study was to quantify the associations between sarcopenia as determined by SARC-F with both depression and hopelessness. DESIGN AND SETTING: This multicenter cohort study involving cross-sectional and longitudinal analyses was conducted in a university hospital and four general hospitals, each with a nephrology center, in Japan. PARTICIPANTS: Participants consisted of 314 CKD patients (mean age 67.6), some of whom were receiving dialysis (228, 73%). MEASUREMENTS: The main exposures were depression, measured using the Center for Epidemiologic Studies Depression (CES-D) questionnaire, and hopelessness, measured using a recently developed 18-item health-related hope scale (HR-Hope). The outcomes were sarcopenia at baseline and one year after, measured using the SARC-F questionnaire. Logistic regression models were applied. RESULTS: The cross-sectional and longitudinal analyses included 314 and 180 patients, respectively. Eighty-nine (28.3%) patients experienced sarcopenia at baseline, and 44 (24.4%) had sarcopenia at the one-year follow-up. More hopelessness (per 10-point lower, adjusted odds ratio [AOR]: 1.33, 95% confidence interval [95% CI] 1.12-1.58), depression (AOR: 1.87, 95% CI 1.003-3.49), age (per 10-year higher, AOR: 1.70, 95% CI 1.29-2.25), being female (AOR: 2.67, 95% CI 1.43-4.98), and undergoing hemodialysis (AOR, 2.92; 95% CI, 1.41-6.05) were associated with a higher likelihood of having baseline sarcopenia. More hopelessness (per 10-point lower, AOR: 1.69, 95% CI 1.14-2.51) and depression (AOR: 4.64, 95% CI: 1.33-16.2) were associated with a higher likelihood of having sarcopenia after one year. CONCLUSIONS: Among patients with different stages of CKD, both hopelessness and depression predicted sarcopenia. Provision of antidepressant therapies or goal-oriented educational programs to alleviate depression or hopelessness can be useful options to prevent sarcopenia.


Assuntos
Insuficiência Renal Crônica , Sarcopenia , Idoso , Estudos de Coortes , Estudos Transversais , Depressão/epidemiologia , Feminino , Esperança , Humanos , Masculino , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Sarcopenia/complicações , Sarcopenia/epidemiologia
6.
Vox Sang ; 96(1): 14-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19121193

RESUMO

BACKGROUND AND OBJECTIVES: Hepatitis A virus (HAV) transmission via contaminated blood products has been reported. Cell-adapted HAV strains are generally used to confirm virus inactivation in manufacturing blood products, but the strains may differ in their sensitivity to inactivation treatment. To select an appropriate cell-adapted HAV strain for virus validation, we compared the inactivation efficiency among four strains under two different physical inactivation treatments: heat and high hydrostatic pressure. MATERIALS AND METHODS: The cell-adapted HAV strains used here were KRM238, KRM003 (subgenotype IIIB), KRM031 (IA), and TKM005 (IB). The strains were treated at 60 degrees C for up to 10 h or under high hydrostatic pressure (up to 420 MPa). The reduction in HAV infectivity was measured by an immunofocus-staining method. RESULTS: The heat treatment at 60 degrees C for 10 h reduced HAV infectivity in the range of 3 to 5 log(10) among the strains; KRM238 and TKM005 were harder to inactivate than the other two. The high hydrostatic pressure treatment at 420 MPa also reduced infectivity in the range of 3 to 5 log(10) among the strains, and KRM031 was easier to inactivate than the other strains. CONCLUSION: Heat treatment and high hydrostatic pressure treatment revealed differences in inactivation efficiencies among cell-adapted HAV strains, and each strain reacted differently depending on the treatment. KRM238 may be the best candidate for virus validation to ensure the safety of blood products against viral contamination, as it is harder to inactivate and it replicates better in cell culture than the other strains.


Assuntos
Segurança do Sangue/métodos , Vírus da Hepatite A/fisiologia , Temperatura Alta , Pressão Hidrostática , Inativação de Vírus , Animais , Linhagem Celular , Chlorocebus aethiops , Vírus da Hepatite A/classificação , Vírus da Hepatite A/crescimento & desenvolvimento , Rim , Especificidade da Espécie , Cultura de Vírus
7.
J Nutr Health Aging ; 23(8): 732-738, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31560031

RESUMO

OBJECTIVES: To validate the SARC-F questionnaire for sarcopenia screening in musculoskeletal disease setting, and to assess improvements in diagnostic accuracy by adding "EBM" (elderly and body mass index information) to the SARC-F. DESIGN: Diagnostic accuracy study. SETTING AND PARTICIPANTS: The center involved in this study was located in an urban area of Kobe City, Japan. People with musculoskeletal disease in the knee, hip, or spine who were scheduled for surgical treatment were included. MEASUREMENTS: Sarcopenia was evaluated using the Asian Working Group for Sarcopenia (AWGS) and the European Working Group on Sarcopenia in Older People (EWGSOP2), which included bioimpedance, handgrip strength, and gait speed. Patients answered the SARC-F questionnaire and their body mass index was measured. SARC-F and "EBM" information were combined into an original score. The sensitivities, specificities, and areas under the receiver operating characteristic curve (AUC) were estimated and compared to identify sarcopenia. RESULTS: A total of 959 patients were included. Sarcopenia by AWGS criteria was identified in 36 (3.8%) patients. SARC-F had a sensitivity of 41.7% and specificity of 68.5%. SARC-F+EBM had a sensitivity of 77.8% and specificity of 69.6%, with substantial improvement in sensitivity (P<0.001). The AUCs for SARC-F and SARC-F+EBM were 0.557 (95% confidence interval [CI] 0.452-0.662) and 0.824 (95% CI 0.762-0.886), respectively (P<0.001). Similar results were obtained when EWGSOP2 criteria were used as the reference standard. CONCLUSION: The SARC-F alone is not adequate for finding cases in musculoskeletal disease settings. SARC-F+EBM significantly improved the sensitivity and overall diagnostic accuracy of the SARC-F for screening sarcopenia. SARC-F+EBM is potentially useful for screening sarcopenia in different ethnic and disease settings.


Assuntos
Programas de Triagem Diagnóstica/normas , Doenças Musculoesqueléticas/fisiopatologia , Sarcopenia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Programas de Rastreamento , Reprodutibilidade dos Testes , Sarcopenia/patologia
8.
J Phys Condens Matter ; 30(45): 455703, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265246

RESUMO

Isovalent substitution of S by Se in LaOBiS2-x Se x has a substantial effect on its electronic structure and thermoelectric properties. To investigate the possible role of BiS2 structural instability, we have studied the local structure of LaOBiS2-x Se x ([Formula: see text]) using temperature dependent Bi L3-edge extended x-ray absorption fine structure measurements. The results reveal that the local structure of the two compounds is significantly different. The BiS2 sub-lattice is largely distorted in LaOBiS2 (x = 0.0), with two in-plane Bi-S1 distances separated by ∼0.4 Å instead LaOBiSSe (x = 1.0) showing much smaller local disorder with two in-plane Bi-Se distances in the plane being separated by ∼0.2 Å. Temperature dependent study shows that the two Bi-S1 distances are characterized by different bond strength in LaOBiS2 (x = 0.0) while it is similar for the Bi-Se distances in LaOBiSSe (x = 1.0). The out of plane Bi-S2 bond is harder in LaOBiSSe indicating that the structural instability of BiS2 layer has large effect on the out-of-plane atomic correlations. The results suggest that the local structure of LaOBiS2-x Se x is an important factor to describe differing electronic and thermal transport of the two compounds.

9.
Transbound Emerg Dis ; 65(3): 727-734, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29285901

RESUMO

Porcine sapelovirus (PSV) is a causative agent of neurological disorders, fertility disorders and dermal lesions of swine. In this study, we isolated two PSV strains, Jpsv477 and Jpsv1315, from swine faecal specimens using a PLC/PRF/5 cell culture system. The PSV infection of PLC/PRF/5 cells induced a cytopathic effect (CPE). Two types of virus particles with identical diameter (~35 nm) but different densities (1.300 and 1.285 g/cm3 ) were observed in the cell culture supernatants. Analysis of the entire genome sequence of Jpsv477 and Jpsv1315 revealed that both strains possess 7,558 nucleotides and the poly (A) tail and have a typical PSV genome organization consisting of a 5' terminal untranslated region (5'UTR), a large open reading frame (ORF), and a 3' terminal untranslated region (3'UTR). The ORF encodes a single polyprotein that is subsequently processed into a leader protein (L), four structural proteins (VP1, VP2, VP3 and VP4) and seven functional proteins (2A, 2B, 2C, 3A, 3B, 3C and 3D). The structural proteins VP1, VP2, VP3 and VP4 have molecular masses of ~35, ~26, ~25 and ~6 kDa. The N-terminal amino acid sequence analysis of VP1, VP2, VP3 and VP4 confirmed that the cleavage sites between VP4 and VP2, VP2 and VP3, and VP3 and VP1 are K/A, Q/G and Q/G, respectively. We further confirmed that HepG2/C3A, Vero E6 and primary green monkey kidney cells (PGMKC) were also susceptible to PSV infection. The stability assay demonstrated that PSV was inactivated by heating at 60°C for 10 min or 65°C for 5 min. The virus also lost infectivity by incubation with 62.5 ppm of NaClO for 30 min.


Assuntos
Picornaviridae/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Linhagem Celular , Fezes/virologia , Picornaviridae/genética , Suínos , Sequenciamento Completo do Genoma
10.
Sci Rep ; 8(1): 2011, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29386537

RESUMO

Recently CeOBiS2 system without any fluorine doping is found to show superconductivity posing question on its origin. Using space resolved ARPES we have found a metallic phase embedded in the morphological defects and at the sample edges of stoichiometric CeOBiS2. While bulk of the sample is semiconducting, the embedded metallic phase is characterized by the usual electron pocket at X point, similar to the Fermi surface of doped BiS2-based superconductors. Typical size of the observed metallic domain is larger than the superconducting correlation length of the system suggesting that the observed superconductivity in undoped CeOBiS2 might be due to this embedded metallic phase at the defects. The results also suggest a possible way to develop new systems by manipulation of the defects in these chalcogenides with structural instability.

11.
J Clin Invest ; 88(6): 1793-801, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1752941

RESUMO

We analyzed the pre-C and core region of hepatitis B virus (HBV) DNA by a polymerase chain reaction in 22 chronic carriers. In 9 hepatitis B e antigen-positive asymptomatic carriers, a single DNA band was detected at the expected size, whereas additional shorter DNA bands were observed in 7 out of 11 patients with chronic hepatitis. The smaller-sized DNAs from one chronic hepatitis patient had various lengths of deletions spanning from 105 to 183 bp in the middle of the core gene, and all deletions included common nucleotide sequences. All of the smaller-sized DNAs from the other patients proved to be variant core genes. They were deleted in similar regions by Southern analysis using oligonucleotide probes. A follow-up study revealed that four out of seven chronic hepatitis patients with a short core gene seroconverted to antibody to hepatitis B e antigen, but those with only a "wild type" did not. In another set of sequence studies, clones isolated from two chronic carriers displayed heterogeneity of the pre-C and core gene which was more often present in sera with normal alanine aminotransferase levels than with abnormal levels. These results suggest that mutant HBV alters the host immune response, and may modulate the clinical course of HBV infection. An alternative possibility is that chronic hepatitis selects for mutant forms.


Assuntos
Portador Sadio/microbiologia , Vírus da Hepatite B/genética , Hepatite B/microbiologia , Adolescente , Adulto , Sequência de Bases , DNA Viral/análise , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase
12.
Rev Sci Instrum ; 78(6): 066107, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17614651

RESUMO

Spectroscopic photoemission and low energy electron microscope (SPELEEM) improved its performance after installation at BL17SU/SPring-8, where a multipolarization-mode undulator is employed to produce circularly and linearly polarized soft x rays. This undulator enables us to study the domain structures of ferromagnetic and antiferromagnetic materials by x-ray magnetic circular dichroism and x-ray magnetic linear dichroism. SPELEEM is used to study light elements (C, N, and O), 3d transition-metal elements and 4f rare earth elements, utilizing a wide range of photon energies. The two cylindrical mirrors adopted in front of SPELEEM ensure an illumination area of 14 x 14 microm(2) on the samples. The lateral resolution of a secondary electron photoemission electron microscope image is estimated to be better than 85 nm, whereas the energy resolution of the instrument is better than 0.4 eV.


Assuntos
Microscopia Eletrônica/instrumentação , Refratometria/instrumentação , Espectrometria por Raios X/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Microscopia Eletrônica/métodos , Refratometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria por Raios X/métodos
13.
J Phys Condens Matter ; 29(6): 064001, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28002037

RESUMO

We have performed potassium (K)-doping dependent photoemission (PES) measurements of picene film on highly oriented pyrolytic graphite (HOPG). K-doping dependent valence band PES data exhibits a shift of the valence band to a higher binding energy, indicative of the charge transfer from the K atoms to the picene film. K-doping dependent PES spectra near the Fermi level (E F) show the appearance and disappearance of a Fermi edge, indicating the metallic properties of the film at certain K concentrations. High-resolution PES spectrum at the lowest measured temperature does not show an opening of the superconducting gap, requesting further studies to explore the superconducting properties of the K-doped picene film. The results will be discussed by comparison with previous and recent spectroscopic studies.

14.
J Dent Res ; 85(7): 627-32, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16798863

RESUMO

Although a recent study suggested the involvement of RANKL and osteoprotegerin (OPG) in the pathogenesis of bone-destructive disease, no study has focused on the RANKL:OPG ratio in the synovial fluid of patients with temporomandibular joint (TMJ) disorder. This communication reports on the concentrations of RANKL and OPG in synovial fluid from TMJ patients and healthy control individuals. In contrast to an unchanged concentration of RANKL, a strong decrease in the concentration of OPG was detected in the synovial fluid from patients with TMJ internal derangement. Treatment with the synovial fluid of osteoarthritis (OA) patients resulted in the high production of osteoclast-like cells from blood mononuclear cells in vitro, as well as in pit formation in dentin slices. The addition of anti-RANKL IgG or OPG attenuated OA-synovial fluid-induced osteoclast formation, suggesting that the increase in the RANKL:OPG ratio in the microenvironment of the joint has the potential to induce osteoclastogenesis in TMJ osteoarthritis.


Assuntos
Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Líquido Sinovial/química , Transtornos da Articulação Temporomandibular/metabolismo , Adulto , Análise de Variância , Estudos de Casos e Controles , Diferenciação Celular , Células Cultivadas , Feminino , Humanos , Imunoglobulina G , Luxações Articulares/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Masculino , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Osteoartrite/metabolismo , Osteoclastos/fisiologia , Osteoprotegerina/análise , Ligante RANK/análise , Líquido Sinovial/metabolismo
15.
Sci Rep ; 6: 27646, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27276997

RESUMO

Recently, ammonia-thermal reaction has been used for molecular intercalation in layered FeSe, resulting a new Lix(NH3)yFe2Se2 superconductor with Tc ~ 45 K. Here, we have used temperature dependent extended x-ray absorption fine structure (EXAFS) to investigate local atomic displacements in single crystals of this new superconductor. Using polarized EXAFS at Fe K-edge we have obtained direct information on the local Fe-Se and Fe-Fe bondlengths and corresponding mean square relative displacements (MSRD). We find that the Se-height in the intercalated system is lower than the one in the binary FeSe, suggesting compressed FeSe4 tetrahedron in the title system. Incidentally, there is hardly any effect of the intercalation on the bondlengths characteristics, revealed by the Einstein temperatures, that are similar to those found in the binary FeSe. Therefore, the molecular intercalation induces an effective compression and decouples the FeSe slabs. Furthermore, the results reveal an anomalous change in the atomic correlations across Tc, appearing as a clear decrease in the MSRD, indicating hardening of the local lattice mode. Similar response of the local lattice has been found in other families of superconductors, e.g., A15-type and cuprates superconductors. This observation suggests that local atomic correlations should have some direct correlation with the superconductivity.

16.
Gene ; 238(2): 367-73, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10570964

RESUMO

Endothelial protein C receptor (EPCR), present on endothelial cells of relatively large veins and arteries, plays a role in the enhancement of protein C activation by the thrombin-thrombomodulin complex. In the present study, we determined the organization and the complete nucleotide sequence of the human EPCR gene using polymerase chain reaction-direct sequencing method. The transcription initiation site of the EPCR gene was also determined by the cap site hunting method, using a cap site cDNA prepared from human placenta. The human EPCR gene spanned approx. 6 kb and was composed of four exons and three introns. All exon-intron boundaries agreed with the GT-AG rule. The 5'-flanking region (300 bp) of the EPCR gene contained a putative AP1-binding site, two Sp1-binding sites and two AP2-binding sites, but not definite TATAA or CCAAT sequences. Fluorescence in situ hybridization analysis showed that the EPCR gene is located in chromosome 20q11.2.


Assuntos
Fatores de Coagulação Sanguínea , Cromossomos Humanos Par 20 , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Sequência de Bases , Células Cultivadas , Mapeamento Cromossômico , DNA , Éxons , Humanos , Íntrons , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Trombomodulina/genética
17.
FEBS Lett ; 429(3): 263-8, 1998 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-9662429

RESUMO

Protein C inhibitor (PCI) is the plasma serine protease inhibitor of activated protein C, the active enzyme of the anticoagulant protein C pathway. Recently, PCI was also detected in human seminal plasma and reproductive organs (testis, seminal vesicle and prostate) suggesting that PCI may also play an important role in the reproductive system. In this study, we cloned the full length of rat PCI cDNA, and determined its amino acid sequence and tissue distribution. We also evaluated the effect of androgen on PCI mRNA expression in seminal vesicles and testes. The isolated 2074-bp rat PCI cDNA was composed of a 47-bp 5'-non-coding region, a 1218-bp coding region of a 406-amino acid precursor protein, a stop codon and a 806-bp 3'-non-coding region. The deduced amino acid sequence of rat PCI showed 85.7%, 64.1% and 62.2% homology with that of mouse, rhesus monkey and human PCIs, respectively. Northern blot analysis showed that the rat PCI mRNA is expressed strongly in the seminal vesicle, moderately in the testis, but not in the liver. PCI mRNA expression in seminal vesicles and testes was found to increase during the process of development, suggesting that it is under androgen control. Subsequently, we examined the effect of castration and/or treatment with 17beta-estradiol or testosterone on PCI mRNA expression in the mature rat seminal vesicles. The PCI mRNA expression in seminal vesicles was significantly decreased after castration or 17beta-estradiol treatment. Testosterone itself did not affect PCI mRNA expression, but treatment in castrated rats significantly enhanced its mRNA expression. These findings suggest that the PCI gene expression in rat seminal vesicles is regulated by androgen.


Assuntos
Androgênios/farmacologia , Inibidor da Proteína C/genética , Glândulas Seminais/metabolismo , Inibidores de Serina Proteinase/genética , Sequência de Aminoácidos , Animais , Castração , Clonagem Molecular , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Macaca mulatta , Masculino , Camundongos , Dados de Sequência Molecular , Inibidor da Proteína C/biossíntese , Ratos , Homologia de Sequência de Aminoácidos , Inibidores de Serina Proteinase/biossíntese , Especificidade da Espécie , Testículo/metabolismo , Distribuição Tecidual
18.
Thromb Haemost ; 83(2): 262-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10739384

RESUMO

Protein C inhibitor (PCI) regulates the anticoagulant protein C pathway by neutralizing activated protein C and thrombin-thrombomodulin complex in the human hemostatic system. In this study, we cloned a full-length bovine PCI cDNA encoding a putative 19-residue signal peptide and a 385-residue mature protein; this showed 70.6%, 70.6%, 57.5% and 59.6% amino acid sequence homology with the human, rhesus monkey, rat and mouse PCIs, respectively. Bovine PCI mRNA (2.1 kb in size) was expressed strongly in the liver, and moderately in the kidney and testis, but not in other tissues tested. Bovine PCI has a putative reactive site peptide bond, Lys-Ser, that is different from the reactive site sequence (Arg-Ser) of other species' PCI. We found that bovine PCI transiently inhibits bovine plasmin, but not human plasmin. Western blot analysis showed that the reactive site of bovine PCI is cleaved during the course of complex formation with bovine plasmin; degraded PCI is released from the complex gradually concomitant with the recovery of plasmin activity. These findings suggest that bovine PCI plays a role not only in the protein C pathway but also in the fibrinolytic activity of bovine hemostatic system.


Assuntos
Antifibrinolíticos/química , Bovinos/sangue , Fibrinolisina/antagonistas & inibidores , Proteína C/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Anticoagulantes/antagonistas & inibidores , Anticoagulantes/química , Sítios de Ligação , Western Blotting , Bovinos/genética , Clonagem Molecular , DNA Complementar , Fibrinolisina/metabolismo , Haplorrinos , Humanos , Cinética , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Ratos , Alinhamento de Sequência , Especificidade da Espécie , Distribuição Tecidual
19.
Bone Marrow Transplant ; 20(11): 993-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9422481

RESUMO

The hepatitis C virus (HCV) infection has, in general, been considered not to affect liver function severely during the course of bone marrow transplantation (BMT) except for late hepatitis which coincided with a decrease in immunosuppressive therapy. We examined serial sera of two patients with positive HCV antibody who underwent allogeneic BMT and found that while the dose of cyclosporin A tapered off, the serum concentration of HCV core protein increased before the occurrence of hepatitis. This suggests that viral reactivation and growth might be one of the important mechanisms of hepatitis after BMT in patients with positive HCV antibody.


Assuntos
Transplante de Medula Óssea , Ciclosporina/uso terapêutico , Anticorpos Anti-Hepatite/imunologia , Hepatite C Crônica/tratamento farmacológico , Imunossupressores/uso terapêutico , Adulto , Feminino , Hepacivirus/isolamento & purificação , Anticorpos Anti-Hepatite/isolamento & purificação , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/imunologia , Humanos , Leucemia Mieloide/complicações , Leucemia Mieloide/terapia , Remissão Espontânea , Proteínas não Estruturais Virais/análise
20.
J Clin Pathol ; 43(4): 298-302, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1692847

RESUMO

To determine the intrahepatic production of tumour necrosis factor alpha (TNF alpha) in chronic liver disease three monoclonal antibodies were used against TNF alpha in immunohistochemical studies of liver tissue sections from patients with chronic liver disease. All three monoclonal antibodies stained infiltrating mononuclear cells. Monoclonal antibody II 7C2 also stained the cytoplasm or nucleus, or both, of a varied number of hepatocytes from nine patients with chronic hepatitis B virus infection, suggesting that the antigenic epitope related to hepatitis B core antigen (HBcAg) crossreacted with II7C2. The other two monoclonal antibodies, III2F3 and IV3E5, stained significantly larger numbers of mononuclear cells in cases of chronic active hepatitis B than in chronic persistent hepatitis B, or hepatitis B related liver cirrhosis. III2F3 stained significantly larger numbers of mononuclear cells in non-A, non-B chronic active hepatitis than in chronic persistent hepatitis B or hepatitis B related liver cirrhosis. These results indicate that TNF alpha is produced and secreted by infiltrating mononuclear cells in focal inflammatory areas of the liver, and suggest that TNF alpha may have a role in the inflammatory activity of chronic liver disease.


Assuntos
Hepatite B/metabolismo , Hepatite C/metabolismo , Hepatite Viral Humana/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Anticorpos Monoclonais , Doença Crônica , Epitopos/imunologia , Feminino , Hepatite B/patologia , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Hepatite C/patologia , Hepatite Crônica/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino
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