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1.
Nature ; 554(7692): 341-345, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29446382

RESUMO

The honeycomb lattice is one of the simplest lattice structures. Electrons and spins on this simple lattice, however, often form exotic phases with non-trivial excitations. Massless Dirac fermions can emerge out of itinerant electrons, as demonstrated experimentally in graphene, and a topological quantum spin liquid with exotic quasiparticles can be realized in spin-1/2 magnets, as proposed theoretically in the Kitaev model. The quantum spin liquid is a long-sought exotic state of matter, in which interacting spins remain quantum-disordered without spontaneous symmetry breaking. The Kitaev model describes one example of a quantum spin liquid, and can be solved exactly by introducing two types of Majorana fermion. Realizing a Kitaev model in the laboratory, however, remains a challenge in materials science. Mott insulators with a honeycomb lattice of spin-orbital-entangled pseudospin-1/2 moments have been proposed, including the 5d-electron systems α-Na2IrO3 (ref. 5) and α-Li2IrO3 (ref. 6) and the 4d-electron system α-RuCl3 (ref. 7). However, these candidates were found to magnetically order rather than form a liquid at sufficiently low temperatures, owing to non-Kitaev interactions. Here we report a quantum-liquid state of pseudospin-1/2 moments in the 5d-electron honeycomb compound H3LiIr2O6. This iridate does not display magnetic ordering down to 0.05 kelvin, despite an interaction energy of about 100 kelvin. We observe signatures of low-energy fermionic excitations that originate from a small number of spin defects in the nuclear-magnetic-resonance relaxation and the specific heat. We therefore conclude that H3LiIr2O6 is a quantum spin liquid. This result opens the door to finding exotic quasiparticles in a strongly spin-orbit-coupled 5d-electron transition-metal oxide.

2.
Biochem Biophys Rep ; 7: 45-51, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29114578

RESUMO

BACKGROUND: Neuromyelitis optica (NMO) is an inflammatory disease caused by the aquaporin (AQP)-4-antibody. Pathological studies on NMO have revealed extensive astrocytic damage, as evidenced by the loss of AQP4 and glial fibrillary acidic protein (GFAP), specifically in perivascular regions with immunoglobulin and complement depositions, although other pathological patterns, such as a loss of AQP4 without astrocyte destruction and clasmatodendrosis, have also been observed. Previous studies have shown that complement-dependent antibody-mediated astrocyte lysis is likely a major pathomechanism in NMO. However, there are also data to suggest antibody-mediated astrocyte dysfunction in the absence of complement. Thus, the importance of complement inhibitory proteins in complement-dependent AQP4-antibody-mediated astrocyte lysis in NMO is unclear. In most of the previous studies, the complement and target cells (astrocytes or AQP4-transfected cells) were derived from different species; however, the complement inhibitory proteins that are expressed on the cell surface cannot protect themselves against complement-dependent cytolysis unless the complements and complement inhibitory proteins are from the same species. To resolve these issues, we studied human astrocytes in primary culture treated with AQP4-antibody in the presence or absence of human complement and examined the effect of complement inhibitory proteins using small interfering RNA (siRNA). METHODS: Purified IgG (10 mg/mL) was obtained from 5 patients with AQP4-antibody-positive NMO, 3 patients with multiple sclerosis (MS), and 3 healthy controls. Confluent human astrocytes transfected with Venus-M1-AQP4-cDNA were incubated with IgG (5% volume). After washing, we cultured the cells with human complements with or without heat inactivation. We observed time-lapse morphological and immunohistochemical changes using a fluorescence microscope. We also evaluated cytotoxicity using a propidium iodide (PI) kit and the lactate dehydrogenase (LDH) assay. RESULT: AQP4-antibody alone caused clustering and degradation followed by endocytosis of membraneous AQP4, thereby resulting in decreased cellular adherence and the shrinkage of astrocytic processes. However, these changes were partially reversed by the removal of IgG in culture. In contrast, following the application of AQP4-antibody and non-heated human complements, the cell bodies and nuclei started to swell. At 3 h, most of the astrocytes had lost mobility and adherence and were eventually destroyed or had swollen and were then destroyed. In addition, the remaining adherent cells were mostly PI-positive, indicating necrosis. Astrocyte lysis caused by rabbit complement occurred much faster than did cell lysis with human complement. However, the cell lysis was significantly enhanced by the transfection of astrocytes with siRNA against human CD55 and CD59, which are major complement inhibitory proteins on the astrocyte membrane. AQP4-antibody-negative IgG in MS or control did not induce such changes. CONCLUSION: Taken together, these findings suggest that both complement-dependent and complement-independent AQP4-antibody-mediated astrocytopathies may operate in NMO, potentially contributing to diverse pathological patterns. Our results also suggest that the effect of complement inhibitory proteins should be considered when evaluating AQP4-antibody-mediated cytotoxicity in AQP4-expressing cells.

3.
Cell Death Dis ; 6: e1607, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25611382

RESUMO

BNIP2 and Cdc42GAP homology (BCH) motif-containing molecule at the carboxyl-terminal region 1 (BMCC1) gene is highly expressed in patients with favorable neuroblastoma (NB). It encodes a 340-kDa protein with a conserved BCH scaffold domain that may regulate signaling networks and multiple cellular functions, including apoptosis. In this study, we determined the mechanism by which BMCC1 promotes apoptosis in human NB and non-NB cells, as BMCC1 is normally expressed in various organs, particularly in neuronal and epithelial tissues. We demonstrated in this report that BMCC1 was induced by DNA damage, one of the triggers of intrinsic apoptosis. Accordingly, we investigated whether BMCC1 expression impacts intracellular signals in the regulation of apoptosis via its C-terminal region containing BCH scaffold domain. BMCC1 decreased phosphorylation of survival signals on AKT and its upstream kinase PDK1. BMCC1 upregulation was correlated with the activation of forkhead box-O3a (FOXO3a) (a downstream inducer of apoptosis, which is suppressed by AKT) and induction of BCL2 inhibitor BIM, suggesting that BMCC1 negatively regulates phosphorylation pathway of AKT, resulted in apoptosis. In addition, we found that BNIP2 homology region of BMCC1 interacts with BCL2. Intrinsic apoptosis induced by DNA damage was enhanced by BMCC1 overexpression, and was diminished by knockdown of BMCC1. Taken together, we conclude that BMCC1 promotes apoptosis at multiple steps in AKT-mediated survival signal pathway. These steps include physical interaction with BCL2 and attenuation of AKT-dependent inhibition of FOXO3a functions, such as transcriptional induction of BIM and phosphorylation of ataxia telangiectasia-mutated (ATM) after DNA damage. We propose that downregulation of BMCC1 expression, which is frequently observed in unfavorable NB and epithelial-derived cancers, may facilitate tumor development by abrogating DNA damage repair and apoptosis.


Assuntos
Apoptose , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Cisplatino/farmacologia , Dano ao DNA , Regulação para Baixo/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Proteínas de Membrana/metabolismo , Neuroblastoma/enzimologia , Neuroblastoma/patologia , Fosforilação/efeitos dos fármacos , Fosfotreonina/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
4.
J Comp Pathol ; 145(2-3): 122-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21453928

RESUMO

An outbreak of disease in Seriola dumerili occurred from August to October in 2007 and 2008. The fish developed lesions of the caudal peduncle, pectoral and/or dorsal fin and the heart. The lesions were characterized by moderate to severe infarction with areas of microabscessation and multifocal granulomatous inflammation associated with the presence of Streptococcus dysgalactiae antigen. This is the first report to describe the immunohistology of the lesions induced in S. dumerili following natural infection with S. dysgalactiae.


Assuntos
Doenças dos Peixes/patologia , Perciformes/microbiologia , Infecções Estreptocócicas/veterinária , Animais , Doenças dos Peixes/microbiologia , Imuno-Histoquímica , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
5.
Neurology ; 75(3): 208-16, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20644148

RESUMO

INTRODUCTION: Loss of aquaporin 4 and glial fibrillary acidic protein (GFAP) with necrosis and demyelination is a prominent pathologic feature of neuromyelitis optica (NMO). However, the clinicopathologic significance of astrocytic damage and its relation with demyelination are unknown. OBJECTIVE: To analyze clinical and pathologic values of a CSF biomarker of astrocytic damage in NMO. METHODS: We measured the levels of GFAP, S100B, myelin basic protein (MBP), and neurofilament H (NF-H) in CSF obtained from patients with NMO (n = 33), multiple sclerosis (MS) (n = 27), acute disseminated encephalomyelitis (ADEM), ischemia, meningitis, and other neurologic disease controls (OND). RESULTS: The CSF-GFAP levels during relapse in NMO (2,476.6 +/- 8,815.0 ng/mL) were significantly higher than those in MS (0.8 +/- 0.4 ng/mL) and OND (0.7 +/- 0.5 ng/mL), and much beyond those in ADEM (14.1 +/- 27.4 ng/mL). The sensitivity and specificity of CSF-GFAP for NMO was 90.9% and 76.9% in all, but the specificity improved above 90% in cases limited to demyelinating diseases. CSF-S100B showed a similar trend but was less remarkable. In contrast, MBP and NF-H are not different between NMO and MS. Following treatments, the CSF-GFAP rapidly decreased to a normal level, but CSF-MBP remained high. There were strong correlations between the CSF-GFAP, CSF-S100B, or CSF-MBP levels and Expanded Disability Status Scale (EDSS) or spinal lesion length in the acute phase (r > 0.6). Only CSF-GFAP correlated with EDSS at 6-month follow-up (r = 0.51) in NMO. CONCLUSIONS: Astrocytic damage reflected by elevated CSF glial fibrillary acidic protein is a clinically relevant, primary pathologic process in neuromyelitis optica, and is far more severe than demyelination.


Assuntos
Astrócitos/patologia , Sistema Nervoso Central/patologia , Proteína Glial Fibrilar Ácida/sangue , Proteína Glial Fibrilar Ácida/líquido cefalorraquidiano , Neuromielite Óptica/líquido cefalorraquidiano , Neuromielite Óptica/patologia , Adulto , Idoso , Anticorpos/sangue , Aquaporina 4/imunologia , Astrócitos/metabolismo , Biomarcadores/líquido cefalorraquidiano , Sistema Nervoso Central/imunologia , Doenças Desmielinizantes/sangue , Doenças Desmielinizantes/líquido cefalorraquidiano , Doenças Desmielinizantes/tratamento farmacológico , Avaliação da Deficiência , Encefalomielite Aguda Disseminada/líquido cefalorraquidiano , Encefalomielite Aguda Disseminada/tratamento farmacológico , Encefalomielite Aguda Disseminada/patologia , Feminino , Seguimentos , Humanos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/patologia , Proteína Básica da Mielina/líquido cefalorraquidiano , Fatores de Crescimento Neural/líquido cefalorraquidiano , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/patologia , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Neuromielite Óptica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/líquido cefalorraquidiano , Estatísticas não Paramétricas
6.
J Comp Pathol ; 143(4): 262-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20570278

RESUMO

Seriola dumerili were infected experimentally with Streptococcus dysgalactiae by oral dosing or immersion. There was moderate mortality after immersion in water containing defined numbers of bacteria, regardless of the dose, whereas the effect on the oral challenge groups depended on the dose of bacteria administered. The characteristic lesions were microabscesses and/or pyogranulomatous inflammation of the caudal peduncle, pectoral and/or dorsal fin, heart and olfactory region. S. dysgalactiae antigen was found within necrotic foci at these sites. There was no difference in distribution of S. dysgalactiae antigen in fish that were exposed by oral or immersion challenge. There was no difference in antigen distribution when fish that died were compared with those that survived and were killed. Immersion exposure is therefore a more effective natural route of infection than oral challenge.


Assuntos
Doenças dos Peixes/microbiologia , Inflamação/veterinária , Infecções Estreptocócicas/veterinária , Animais , Doenças dos Peixes/patologia , Imuno-Histoquímica , Inflamação/microbiologia , Inflamação/patologia , Perciformes , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia , Streptococcus
7.
J Neurol Neurosurg Psychiatry ; 80(5): 575-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19372295

RESUMO

BACKGROUND: Neuromyelitis optica (NMO) is a neurological inflammatory disease associated with autoimmunity to aquaporin 4, predominantly localised in astrocytic foot processes. Recent studies have revealed that loss of aquaporin 4 and glial fibrillar acidic protein (GFAP) is a prominent feature of NMO lesions, suggesting astrocytic impairment. OBJECTIVE: To reveal a useful clinical biomarker of NMO. METHODS: Enzyme-linked immunosorbent assays were carried out for astrocytic markers GFAP and S100B in CSFs, obtained from the patients with NMO (n = 10) and multiple sclerosis (MS) (n = 10) manifesting acute myelitis, acute disseminated encephalomyelitis (ADEM) (n = 3), spinal infarction (n = 3), and other neurological diseases (OND) (n = 5). RESULTS: The CSF-GFAP levels during relapse in NMO (7666.0 (SD 15 266.5) ng/ml) were significantly over several thousand times higher than those in MS (0.7 (1.5)) or OND (0.6 (0.3)), and considerably higher than those in spinal infarction (354.7 (459.0)) and ADEM (0.4 (0.2)). They returned close to normal levels along with clinical improvement soon after corticosteroid therapy in NMO. There were strong correlations between the CSF-GFAP or S100B levels and expanded disability status scales or spinal lesion length in NMO (r>0.9). CONCLUSIONS: CSF-GFAP and S100B may be clinically useful biomarkers in NMO, and astrocytic damage is strongly suggested in the acute phase of NMO.


Assuntos
Astrócitos/patologia , Proteína Glial Fibrilar Ácida/líquido cefalorraquidiano , Neuromielite Óptica/líquido cefalorraquidiano , Adulto , Idoso , Aquaporina 4/genética , Biomarcadores , Encefalomielite Aguda Disseminada/líquido cefalorraquidiano , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas S100/líquido cefalorraquidiano , Medula Espinal/patologia
8.
J Comp Pathol ; 140(1): 25-30, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19059602

RESUMO

Fish of the species Seriola dumerili were infected experimentally with the pathogen Streptococcus dysgalactiae. Intradermal (ID) injection of S. dysgalactiae resulted in moderate mortality regardless of the dose of bacteria injected, whereas intraperitoneal (IP) injection caused greatest mortality in the group of fish receiving the highest dose of bacteria (10(9) colony forming units/ml). On necropsy examination of affected fish, the most striking change was microabscessation and/or granulomatous inflammation of the heart, caudal peduncle, pectoral and/or dorsal fin and olfactory region. The lesions in the atrial myocardium and arterial cone consisted of severe arterial thrombosis, granulomatous valvular endocarditis and epicarditis. S. dysgalactiae was cultured from these lesions and S. dysgalactiae antigen was demonstrated by immunohistochemistry within these tissues. The mortality in these fish is therefore considered to reflect bacterial septicaemia and systemic granulomatous inflammatory disease.


Assuntos
Doenças dos Peixes/microbiologia , Doenças dos Peixes/patologia , Infecções Estreptocócicas/veterinária , Streptococcus , Animais , Peixes , Coração/microbiologia , Injeções Intradérmicas , Injeções Intraperitoneais , Miocárdio/patologia , Condutos Olfatórios/microbiologia , Condutos Olfatórios/patologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
9.
J Neurol Neurosurg Psychiatry ; 79(9): 1075-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18420727

RESUMO

BACKGROUND: Intractable hiccup and nausea (IHN) are unique symptoms in neuromyelitis optica (NMO). Recent studies have strongly suggested that the pathogenesis of NMO is closely associated with anti-aquaporin-4 (AQP4) antibody. However, clinical implications of IHN and the relationship with anti-AQP4 antibody remain unknown. METHODS: The past medical records of 35 patients with seropositivity for anti-AQP4 antibody were reviewed. We also followed the titres of anti-AQP4 antibody in a patient with NMO, who had newly developed IHN. RESULTS: Of the 35 patients, 15 patients (43%) had episodes of IHN. There was a total of 35 episodes of IHN in these 15 patients and, of the 35 episodes, hiccup was seen in 23 episodes (66%) and nausea was seen in 28 episodes (80%). The IHN frequently preceded (54%) or accompanied (29%) myelitis or optic neuritis. The IHN was often preceded by an episode of viral infection. The titres of anti-AQP4 antibody were remarkably increased when the intractable hiccup appeared in a case. CONCLUSIONS: IHN could be a clinical marker for the early phase of an exacerbation. Careful observation may be needed when INH is seen in patients with NMO, and the early initiation of the treatment could prevent subsequent neurological damage.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Aquaporina 4/imunologia , Soluço/diagnóstico , Soluço/epidemiologia , Náusea/diagnóstico , Náusea/epidemiologia , Neuromielite Óptica , Doença Aguda , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/imunologia , Prevalência
10.
J Pept Res ; 66(2): 49-58, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16000118

RESUMO

A 12-residue marinostatin [MST(1-12): (1)FATMRYPSDSDE(12)] which contains two ester linkages of Thr(3)-Asp(9) and Ser(8)-Asp(11) strongly inhibits subtilisin. In order to study the relationship between the inhibitory activity, structure, and stability of MST, MST analogs were prepared by changing ester linkages to a disulfide linkages. The analogs without the disulfide linkage between 3 and 9 positions lost their inhibitory activity. The K(i) value of 1SS(C(3)-C(9)) ((1)FACMRYPSCSDE(12)), which has a single disulfide linkage of Cys(3)-Cys(9) was comparable with those of MST(1-12) and MST-2SS ((1)FACMRYPCCSCE(12)), a doubly linked analog of Cys(3)-Cys(9) and Cys(8)-Cys(11). However, 1SS(C(3)-C(9)) and MST-2SS showed temporary inhibition, but not MST(1-12): These analogs were inactivated after incubation with subtilisin for 30 min, and were specifically hydrolyzed at the reactive site. (1)H NMR study showed that 1SS(C(3)-C(9)) has two conformations, which contain a cis- (70%) or trans- (30%) Pro residue, while MST-2SS as well as MST(1-12) takes a single conformation containing only a cis-Pro residue. Hydrogen-deuterium exchange rate of the Arg(5) (P1') NH proton of the MST analogs was about 100 times faster than that of MST(1-12). These results indicate that the linkage between the positions 8 and 11 plays a role for fixing the cis-conformation of the Pro(7) residue, and that the linkage between 3 and 9 is indispensable for the inhibition, but not enough for stable protease-inhibitor complex.


Assuntos
Transportadores de Cassetes de Ligação de ATP/química , Proteínas de Bactérias/química , Inibidores de Proteases/química , Precursores de Proteínas/química , Subtilisina/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/síntese química , Transportadores de Cassetes de Ligação de ATP/farmacologia , Sequência de Aminoácidos , Proteínas de Bactérias/síntese química , Proteínas de Bactérias/farmacologia , Medição da Troca de Deutério , Dissulfetos/química , Ésteres/química , Ressonância Magnética Nuclear Biomolecular , Prolina/química , Inibidores de Proteases/farmacologia , Conformação Proteica , Precursores de Proteínas/síntese química , Precursores de Proteínas/farmacologia , Relação Estrutura-Atividade
11.
Neurology ; 60(11): 1799-804, 2003 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-12796534

RESUMO

OBJECTIVE: To study dysferlin gene mutations and genotype-phenotype correlations in Japanese patients with Miyoshi myopathy (MM). BACKGROUND: MM is an autosomal recessive distal muscular dystrophy that arises from mutations in the dysferlin gene. This gene is also mutated in families with limb girdle muscular dystrophy 2B. METHODS: The authors examined 25 Japanese patients with MM. Genomic DNA was extracted from the peripheral lymphocytes of the patients. The PCR products of each of 55 exons were screened by single strand conformation polymorphism or direct sequencing from the PCR fragments. RESULTS: The authors identified 16 different mutations in 20 patients with MM; 10 were novel. Mutations in Japanese patients are distributed along the entire length of the gene. CONCLUSIONS: Four mutations (C1939G, G3370T, 3746delG, and 4870delT) are relatively more prevalent in this population, accounting for 60% of the mutations in this study. This study revealed that the G3370T mutation was associated with milder forms of MM and the G3510A mutation was associated with a more severe form.


Assuntos
Proteínas de Membrana , Proteínas Musculares/genética , Distrofias Musculares/diagnóstico , Distrofias Musculares/genética , Mutação , Adulto , Creatina Quinase/sangue , Análise Mutacional de DNA , Disferlina , Feminino , Genótipo , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Distrofias Musculares/epidemiologia , Fenótipo , Polimorfismo Genético
12.
Dis Aquat Organ ; 48(2): 143-8, 2002 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-12005236

RESUMO

Molecular virological analyses of 8 Japanese VHSV (viral hemorrhagic septicemia virus) isolates from wild and farmed Japanese flounder Paralichthys olivaceus were performed to investigate their genetic relatedness to American and European isolates of VHSV. Phylogenetic analyses based on the partial nucleotide sequences of G and P genes revealed that there are 2 genogroups of VHSV in Japan. The first one represented by the Obama25 isolate is closely related to the American isolates (Genogroup I) while the other, the KRRV9601 isolate, is closely related to the traditional European isolates (Genogroup III). The 2 types of Japanese VHSV showed differences in the relative mobility of the G protein and intensity of the antibody reaction on the P and M proteins. The Obama25 type of VHSV is widely distributed as a native virus in the coastal areas of western Japan and has been responsible for the occurrence of VHSV infection in farmed Japanese flounder while the KRRV9601 isolate is considered to have been introduced from a foreign country.


Assuntos
Doenças dos Peixes/virologia , Linguado , Novirhabdovirus/classificação , Novirhabdovirus/genética , Infecções por Rhabdoviridae/veterinária , Proteínas do Envelope Viral/genética , Animais , Sequência de Bases , Western Blotting/veterinária , Eletroforese em Gel de Poliacrilamida/veterinária , Europa (Continente) , Genes Virais , Japão , Filogenia , RNA Viral/química , Infecções por Rhabdoviridae/virologia , Análise de Sequência de RNA/veterinária , Estados Unidos
13.
Jpn J Clin Oncol ; 31(9): 447-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11689600

RESUMO

Myxoid liposarcoma can frequently metastasize to extrapulmonary sites. We present two cases of myxoid liposarcoma metastatic to the epidural space. Both patients complained of back pain, but plain radiography revealed no abnormality. MR imaging clearly demonstrated metastatic tumors in the epidural space, but no involvement of vertebra. When patients with myxoid liposarcoma complain of back pain, metastasis in the epidural space should be considered even in patients without bone involvement.


Assuntos
Espaço Epidural/patologia , Lipossarcoma Mixoide/secundário , Neoplasias de Tecidos Moles/patologia , Adulto , Feminino , Humanos , Laminectomia , Lipossarcoma Mixoide/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecidos Moles/cirurgia
14.
J Clin Ultrasound ; 29(7): 384-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11579400

RESUMO

PURPOSE: It has been reported that an intra-abdominal pressure (IAP) above 15 mm Hg may cause oliguria and that an IAP above 25 mm Hg may cause anuria. Because Valsalva's maneuver yields an IAP exceeding 180 mm Hg, it is presumed to affect renal perfusion. We evaluated the ability of power Doppler sonography to depict the changes in renal blood flow during Valsalva's maneuver. METHODS: Seven healthy men aged 21-24 years and 1 50-year-old man with massive ascites participated in the study. With each healthy subject lying in a supine position, longitudinal power Doppler sonograms of the kidney were obtained and analyzed semiquantitatively during Valsalva's maneuver. Also, in the patient with massive ascites, power Doppler sonography was performed before and after paracentesis. RESULTS: Along with an increase in IAP, monitored as expiratory pressure during Valsalva's maneuver, power Doppler signals decreased as indicated by both visual impression and computer scores. In the patient with massive ascites, signal intensity increased after paracentesis. CONCLUSIONS: Our results demonstrated that an increase in IAP within the physiologic range affects renal perfusion and that power Doppler sonography depicts semiquantitatively the change in renal blood flow.


Assuntos
Rim/irrigação sanguínea , Rim/diagnóstico por imagem , Manobra de Valsalva , Adulto , Humanos , Masculino , Fluxo Sanguíneo Regional , Sensibilidade e Especificidade , Ultrassonografia Doppler
15.
Am J Ophthalmol ; 132(4): 485-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11589867

RESUMO

PURPOSE: To evaluate the effects of latanoprost and unoprostone on the intraocular pressure (IOP) and on the tonographic outflow facility in glaucoma patients when used alone or in combination. DESIGN: Open label randomized clinical study. METHODS: Fifty-two patients (52 eyes) with primary open-angle glaucoma were randomly divided into two groups. One group initially received only latanoprost 0.005% once daily and the other group, only unoprostone 0.12% twice daily. The study period was 12 weeks: in the first 6 weeks, latanoprost or unoprostone was given as monotherapy, and in the last 6 weeks, patients received both drugs. IOP was measured every 2 weeks by one investigator masked to the medication received by patients during the study period in the same hour as on the baseline day. At Weeks 0, 6, and 12, the coefficient of aqueous outflow was measured by tonography. RESULTS: With latanoprost monotherapy, the baseline IOP of 22.9 +/- 2.4 mm Hg (mean +/- SD) decreased to 16.9 +/- 2.1 mm Hg (P<.01). When unoprostone was added to latanoprost, the IOP remained at 16.7 +/- 2.5 mm Hg. With unoprostone monotherapy, the baseline IOP of 22.7 +/- 2.1 mm Hg decreased to 19.4 +/- 2.4 mm Hg (P<.01). When latanoprost was added to unoprostone, the IOP decreased to 16.8 +/- 1.7 mm Hg (P<.01). There was no significant change in the coefficient of aqueous outflow with monotherapy or the combined use of the drugs. CONCLUSIONS: The combination of latanoprost and unoprostone does not result in a more potent hypotensive effect than latanoprost alone.


Assuntos
Anti-Hipertensivos/uso terapêutico , Dinoprosta/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Pressão Intraocular/efeitos dos fármacos , Prostaglandinas F Sintéticas/uso terapêutico , Adulto , Idoso , Anti-Hipertensivos/administração & dosagem , Humor Aquoso/metabolismo , Dinoprosta/administração & dosagem , Dinoprosta/análogos & derivados , Quimioterapia Combinada , Feminino , Glaucoma de Ângulo Aberto/metabolismo , Humanos , Latanoprosta , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Prostaglandinas F Sintéticas/administração & dosagem , Tonometria Ocular , Resultado do Tratamento
16.
Anal Biochem ; 295(2): 203-13, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11488623

RESUMO

Evanescent wave biosensor has been recently employed as a powerful tool for analyses of macromolecular interactions. In the present study, evanescent wave biosensor analysis was developed to analyze the heparin-protein interaction using as ligands a series of heparin derivatives regioselectively desulfated by chemical methods, particularly to evaluate the effect of each sulfate group of heparin. The method for immobilizing heparin on the cuvette of the evanescent wave biosensor equipment was optimized to obtain the high response required for accurate measurement. The best result was achieved when the amino group introduced at the reducing end of heparin was coupled with carboxymethyl dextran on the surface of the cuvette using glycolchitosan as a multivalent linker. The established system appeared to describe well the interactions of heparin with such proteins as acidic and basic fibroblast growth factors and tissue factor pathway inhibitor.


Assuntos
Heparina/química , Lipoproteínas/química , Proteínas/química , Técnicas Biossensoriais , Quitina/análogos & derivados , Quitosana , Dextranos , Fator 1 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/química , Cinética , Ligantes
17.
Spine (Phila Pa 1976) ; 26(16): 1817-9, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11493858

RESUMO

STUDY DESIGN: Case report. OBJECTIVE: To point out that presacral schwannoma can display markedly cystic degeneration. SUMMARY OF BACKGROUND DATA: Benign schwannoma sometimes displays degenerative changes, such as cyst formation, calcification, hemorrhage, and hyalinization. Usually these degenerations are partially seen in the tumors. METHODS: Medical history, physical findings, imaging features, and histologic findings were reviewed in a case with a large presacral schwannoma. RESULTS: A 62-year-old woman presented with an 18-month history of right sciatic pain. Magnetic resonance images detected a large cystic, presacral tumor. Initially the tumor was misdiagnosed as a cystic ovarian tumor. Preoperative diagnostic workup led to the diagnosis of cystic schwannoma. Intralesional curettage achieved good pain relief. CONCLUSIONS: This tumor was unusual in its totally cystic appearance and resemblance to a cystic ovarian tumor or anterior sacral meningocele. Preoperative diagnosis is important to prevent major neurologic deficit at surgery.


Assuntos
Cistos/patologia , Neurilemoma/patologia , Neoplasias Retroperitoneais/patologia , Espaço Retroperitoneal/patologia , Sacro/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Meningocele/diagnóstico , Pessoa de Meia-Idade , Neurilemoma/cirurgia , Neoplasias Ovarianas/diagnóstico , Neoplasias Retroperitoneais/cirurgia , Espaço Retroperitoneal/cirurgia , Sacro/cirurgia
18.
Protein Expr Purif ; 21(1): 192-200, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11162406

RESUMO

A hybrid of Autographa californica nuclear polyhedrosis virus and Bombyx mori nuclear polyhedrosis virus, which is infectious to both Spodoptera frugiperda and Bombyx mori, was prepared in our previous study. Two recombinant hybrid baculoviruses, carrying cDNAs of human acidic and basic fibroblast growth factors, respectively, were successfully constructed in this study, for the large-scale production of human aFGF and bFGF using silkworm as host. These recombinant viruses were used to inoculate silkworm larvae. After the infection, the recombinant proteins were not found in the hemolymph. Such nonsecretion from cells has also been observed in the established insect cell lines, Sf21 and Tn-5. Tissue distribution analysis indicated that the expressed products were mainly located in fat body and the production of the recombinant aFGF and bFGF was maximal at around 80 h postinfection. Therefore, silkworm larvae infected with recombinant viruses were dissected and fat bodies were collected for the purification of recombinant aFGF and bFGF. The expression levels in both cases were estimated to be as high as approximately 600-700 microg per larva. Furthermore, the recombinant proteins were characterized and their biological activities were evaluated by in vitro bioassay using cell culture.


Assuntos
Encéfalo/metabolismo , Fator 1 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/genética , Adulto , Sequência de Aminoácidos , Animais , Baculoviridae , Sequência de Bases , Bombyx , DNA Complementar , Fator 1 de Crescimento de Fibroblastos/isolamento & purificação , Fator 2 de Crescimento de Fibroblastos/isolamento & purificação , Biblioteca Gênica , Vetores Genéticos , Hemolinfa/química , Humanos , Larva , Masculino , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Transfecção/métodos
19.
J Neural Transm Suppl ; (58): 135-42, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11128603

RESUMO

Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS.


Assuntos
Caspase 1/fisiologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Encéfalo/citologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA , Humanos
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