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1.
Phys Rev Lett ; 128(7): 072501, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35244436

RESUMO

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470

2.
Public Health ; 210: 34-40, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35870319

RESUMO

OBJECTIVES: Contact tracing for COVID-19 relies heavily on the cooperation of individuals with authorities to provide information of contact persons. However, few studies have clarified willingness to cooperate and motivation to provide information for contact tracing. This study sought to describe willingness to cooperate and motivation to report contact persons for COVID-19 contact tracing among citizens in Japan, and to assess any associated sociodemographic factors. STUDY DESIGN: Cross-sectional study. METHODS: This was an online-based survey using quota sampling. Participants were asked about their willingness to cooperate in reporting contacts for COVID-19 contact tracing if they tested positive. Participants also responded to questions regarding their reasons for cooperating or not cooperating and provided sociodemographic data. Multiple logistic regression analysis was performed to clarify associations between sociodemographic factors and willingness to cooperate. RESULTS: This study included 2844 participants. The proportion of participants who were not willing to cooperate in reporting contacts was 27.6%, with their main reasons being concerns about causing trouble for the other person and being criticised for revealing their names. Willingness to cooperate was lower among men, young adults and those with an educational level less than a university degree. CONCLUSIONS: To improve the effectiveness of contact tracing, educational campaigns, such as reducing the fear and stigma associated with COVID-19, may be important. Furthermore, it is essential to understand that individuals may have contacts whom they do not wish to disclose to others and to be considerate when handling such situations.


Assuntos
COVID-19 , Busca de Comunicante , COVID-19/epidemiologia , Estudos Transversais , Humanos , Japão/epidemiologia , Masculino , Inquéritos e Questionários , Adulto Jovem
3.
Eur J Clin Microbiol Infect Dis ; 34(1): 83-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25070493

RESUMO

Several antibiotic combinations have demonstrated increased activity against multidrug-resistant Pseudomonas aeruginosa (MDRP) in vitro compared with a single antibiotic. The aim of this study was to investigate the activity against MDRP of some aminoglycosides in combination with monobactam, piperacillin (PIPC), and carbapenem. Clinical isolates of MDRP were collected between November 2010 and October 2012 from patients in Tokyo Medical University Hospital, Tokyo (1,015 beds). Our new method was designed to evaluate three concentrations around the breakpoint of each drug using the Checkerboard method. The aminoglycosides tested were amikacin (AMK), tobramycin (TOB), and arbekacin (ABK). Ciprofloxacin, PIPC, and biapenem (BIPM), which have been reported to demonstrate combination effects, were also tested. Sixty-six MDRP strains were identified from the 2,417 P. aeruginosa strains. Of the 66, 27 tested positive for metallo-ß-lactamase (MBL). Aztreonam (AZT) with AMK or ABK was the most effective against MDRP. PIPC with AMK or ABK were somewhat effective. AZT with AMK or ABK were more effective against MBL-positive strains than MBL-negative strains. However, PIPC with AMK or ABK were more effective against MBL-negative strains than MBL-positive strains. Combination activities showed differences between MBL-positive and MBL-negative strains.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Aminoglicosídeos/farmacologia , Aminoglicosídeos/uso terapêutico , Antibacterianos/uso terapêutico , Quimioterapia Combinada/métodos , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Tóquio , beta-Lactamas/farmacologia , beta-Lactamas/uso terapêutico
4.
Nat Genet ; 19(3): 271-3, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9662402

RESUMO

Ossification of the posterior longitudinal ligament of the spine (OPLL) is a common form of human myelopathy caused by a compression of the spinal cord by ectopic ossification of spinal ligaments. To elucidate the genetic basis for OPLL, we have been studying the ttw (tiptoe walking; previously designated twy) mouse, a naturally occurring mutant which exhibits ossification of the spinal ligaments very similar to human OPLL (refs 3,4). Using a positional candidate-gene approach, we determined the ttw phenotype is caused by a nonsense mutation (glycine 568 to stop) in the Npps gene which encodes nucleotide pyrophosphatase. This enzyme regulates soft-tissue calcification and bone mineralization by producing inorganic pyrophosphate, a major inhibitor of calcification. The accelerated bone formation characteristic of ttw mice is likely to result from dysfunction of NPPS caused by predicted truncation of the gene product, resulting in the loss of more than one-third of the native protein. Our results may lead to novel insights into the mechanism of ectopic ossification and the aetiology of human OPLL.


Assuntos
Mutação , Ossificação do Ligamento Longitudinal Posterior/enzimologia , Ossificação do Ligamento Longitudinal Posterior/genética , Pirofosfatases/genética , Animais , Sequência de Bases , Análise Mutacional de DNA , DNA Complementar , Modelos Animais de Doenças , Feminino , Ligação Genética , Humanos , Ligamentos Longitudinais , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Dados de Sequência Molecular , Coluna Vertebral/anormalidades
5.
R Soc Open Sci ; 9(9): 211869, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36147936

RESUMO

Marine organisms normally swim at elevated speeds relative to cruising speeds only during strenuous activity, such as predation or escape. We measured swimming speeds of 29 ram ventilating sharks from 10 species and of three Atlantic bluefin tunas immediately after exhaustive exercise (fighting a capture by hook-and-line) and unexpectedly found all individuals exhibited a uniform mechanical response, with swimming speed initially two times higher than the cruising speeds reached approximately 6 h later. We hypothesized that elevated swimming behaviour is a means to increase energetic demand and drive the removal of lactate accumulated during capture via oxidation. To explore this hypothesis, we estimated the mechanical work that must have been spent by an animal to elevate its swim speed and then showed that the amount of lactate that could have been oxidized to fuel it comprises a significant portion of the amount of lactate normally observed in fishes after exhaustive exercise. An estimate for the full energetic cost of the catch-and-release event ensued.

6.
J Hosp Infect ; 118: 1-6, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34437982

RESUMO

BACKGROUND: Although sink- and drain-related carbapenemase-producing Enterobacterales transmission has been reported previously, there is limited research regarding the transmission of extended-spectrum ß-lactamase (ESBL)-producing Enterobacterales. AIM: To investigate nosocomial ESBL-producing Klebsiella pneumoniae transmission via patient sinks and drains on a general surgical hospital ward. METHODS: ESBL-producing K. pneumoniae transmission on a surgical ward at Tokyo Medical University Hospital (built in July 2019) from July 2019 to February 2020 was investigated. Information regarding the relatedness of the isolates from the patients and the environment was provided by whole-genome sequence analysis. FINDINGS: Four clinical isolates of K. pneumoniae (TUM19831, TUM19832, TUM19833 and TUM19834) were detected during the study. TUM19831 was identified prior to moving to the new building and was detected again in the new building. TUM19832 and TUM19833 were detected in July 2019, and TUM19834 was detected in December 2019. TUM19835 and TUM19836 were detected in two different sinks and drains in July 2019, while a further two sinks and drains tested positive for TUM19837 and TUM19838 in February 2020. Whole-genome analysis revealed that all strains were ST307 and CTXM15 sequence types, and the isolates were indistinguishable by genetic analysis. Due to inadequate removal of the slime biofilm coating, the sinks needed to be cleaned again before TUM19837 and TUM19838 could be detected. CONCLUSIONS: This study demonstrated the transmission of indistinguishable ESBL-producing K. pneumoniae strains from sinks and drains in the patient area of a general surgical hospital ward. There is a need to recognize this risk and develop optimal management strategies for plumbing systems in hospitals and other healthcare settings.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , beta-Lactamases/genética , Hospitais , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Polimorfismo de Nucleotídeo Único
7.
J Exp Med ; 159(4): 1132-48, 1984 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-6368735

RESUMO

The natural resistance of F1 hybrid mice against parental bone marrow grafts is thought to be mediated by natural killer (NK)-like effector cells. However, unlike the NK cell activity against a wide range of tumors and normal cells, hybrid resistance is characterized by the immunogenetic specificity controlled by a set of unique noncodominant genes denoted as Hh. Two alternative hypotheses can account for the specificity. Thus, the specificity may reflect either the Hh restriction of effectors or the Hh gene control of mechanisms regulating non-Hh-restricted effector activity. In this study, therefore, we tested the recognition specificity of putative effectors mediating hybrid resistance in lethally irradiated H-2b/d and H-2b/k F1 hybrid mice to the engraftment of parental H-2b bone marrow. As a direct means of defining the effector specificity, rejection of parental bone marrow grafts was subjected to competitive inhibition in situ by irradiated tumor cells. Of the 16 independent lines of lymphoma and other hemopoietic tumor cells tested, the ability to inhibit hybrid resistance was the exclusive property of all tumors derived from mice homozygous for the H-2Db region, regardless of whether the tumor cells were susceptible or resistant to NK cell-mediated cytotoxicity in vitro. Four cell lines heterozygous for the H-2Db were noninhibitory, including one that is susceptible to natural killing. Pretreatment of the F1 hosts with an interferon inducer augmented the resistance with no alteration in the recognition specificity of effector cells. Therefore, natural resistance to parental H-2b bone marrow grafts was mediated by effectors restricted by the H-2Db/Hh-1b gene(s), and not by the nonrestricted NK cells detectable in conventional in vitro assays.


Assuntos
Transplante de Medula Óssea , Citotoxicidade Imunológica , Antígenos H-2/genética , Células Matadoras Naturais/imunologia , Quimera por Radiação , Animais , Ligação Competitiva , Células da Medula Óssea , Cruzamentos Genéticos , Feminino , Antígenos H-2/imunologia , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Linfoma/patologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Transplante de Neoplasias , Poli I-C/farmacologia , Neoplasias Esplênicas/genética , Neoplasias Esplênicas/imunologia , Neoplasias Esplênicas/patologia
8.
J Exp Med ; 138(4): 973-88, 1973 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-4542738

RESUMO

The primary antibody response elicited from mouse spleen explants by conjugates of the 3-nitro-5-iodo-4-hydroxyphenylacetic acid (NIP) hapten consisted mostly of the IgA class. Poly-L-lysine, pneumococcal polysaccharide Type SIII, keyhole limpet hemocyanin, and sheep erythrocytes were effective carriers in this system, whereas chicken globulin was not. The anti-NIP response against all of the immunogenic conjugates was detectable in culture media 4 days after explantation and immunization, and reached peak titers by 8-10 days. IgA was identified by sucrose gradient velocity centrifugation in conjunction with the use of a class-specific antiserum. The media collected at 4 days contained low titers of IgM antibody, whereas the peak response at 8 days consisted almost entirely of IgA. The primary response IgA secreted by the spleen fragments was characterized as polymeric by its sedimentation rate through a sucrose gradient, and as polyvalent by its drastically greater avidity for NIP(14)BSA than for free NIP-aminocaproic acid. Its haptenated phage-inactivating activity was abolished by treatment with 0.1 M 2-mercaptoethanol. These experiments indicate that precursor cells existing in the spleen before primary immunization can give rise to production of polymeric IgA.


Assuntos
Formação de Anticorpos , Imunoglobulina A , Baço/imunologia , Animais , Anticorpos Anti-Idiotípicos , Células Produtoras de Anticorpos , Proteínas de Transporte , Técnicas de Cultura , Feminino , Haptenos , Soros Imunes , Imunoglobulina A/análise , Imunoglobulina A/biossíntese , Imunoglobulina M/análise , Iodo , Camundongos , Camundongos Endogâmicos C57BL , Nitrofenóis , Fenilacetatos
9.
J Exp Med ; 138(1): 130-42, 1973 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-4577615

RESUMO

The immune response to SRBC was measured in the spleens of adult thymectomized, total body irradiated mice injected with various combinations of thymus and bone marrow cells together with thymic humoral factor (THF). It was found that the number of plaque-forming cells was significantly increased when THF was given in vivo immediately after thymus cell administration or when thymus cells were incubated in THF before injection. On the other hand, bone marrow cells equally treated did not manifest any T cell activity, since THF-treated bone marrow cells were not able to substitute thymus cells in the system used. The results accumulated in the present experiments indicate, therefore, that the target cells for THF activity are thymus cells which acquire a higher T helper cell capacity after THF treatment.


Assuntos
Formação de Anticorpos , Linfócitos/imunologia , Timo/imunologia , Animais , Formação de Anticorpos/efeitos da radiação , Células Produtoras de Anticorpos , Linfócitos B/imunologia , Medula Óssea/imunologia , Células da Medula Óssea , Isótopos do Cobalto , Eritrócitos/imunologia , Técnica de Placa Hemolítica , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos , Efeitos da Radiação , Ovinos/imunologia , Baço/imunologia , Linfócitos T/imunologia , Timectomia , Extratos de Tecidos/administração & dosagem
10.
J Phys Condens Matter ; 32(43): 435703, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32674076

RESUMO

We have grown thin films of CaAgAs by molecular beam epitaxy, which was theoretically proposed to be a topological insulator. The temperature dependence of resistivity and the carrier concentration at 4 K were similar to the reported results of bulk samples. However, the magnetoresistance exhibited a steep increase at low magnetic fields, a behavior not observed for bulk samples. This steep increase of resistivity is ascribable to the weak antilocalization effect and provides clues to the nature of the topological surface state of CaAgAs.

11.
Neotrop Entomol ; 49(3): 392-411, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32172389

RESUMO

So far, six species of Oxeoschistus Butler, including its junior synonym Dioriste Thieme, were listed from Central America, with five of them from Costa Rica alone, which appears to represent the highest regional diversity of this Neotropical montane butterfly genus. Our research based on field work, morphological studies and barcode analysis proved that one record is a misunderstanding perpetuated in scientific literature for over a century: Oxeoschistus cothonides Grose-Smith is identified here as an individual form of the female of O. cothon Salvin. The presence of Oxeoschistus tauropolis (Westwood) in Costa Rica, subject to some controversy, is confirmed, and a new local subspecies is described from Costa Rica, O. tauropolis mitsuko Pyrcz & Nakamura n. ssp. Specific status of O. euriphyle Butler is reinstated based on morphological and molecular data. A new subspecies O. hilara lempira Pyrcz n. ssp. is described from Honduras. O. puerta submaculatus Butler is reported for the first time from the Darién region on the Panama-Colombia border. Species relationships are preliminarily evaluated based on COI data concluding, among others, that O. hilara and O. euriphyle are less closely related than previously assumed. Altitudinal and distributional data are revised, and ecological and behavioural information of all the species of Central American Oxeoschistus is provided.


Assuntos
Distribuição Animal , Borboletas/classificação , Floresta Úmida , Animais , Borboletas/anatomia & histologia , Colômbia , Costa Rica , Feminino , Masculino , Panamá , Filogenia
12.
J Cell Biol ; 152(2): 361-73, 2001 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-11266452

RESUMO

The macrophage colony stimulating factor (M-CSF) and alpha(v)beta(3) integrins play critical roles in osteoclast function. This study examines M-CSF- and adhesion-induced signaling in prefusion osteoclasts (pOCs) derived from Src-deficient and wild-type mice. Src-deficient cells attach to but do not spread on vitronectin (Vn)-coated surfaces and, contrary to wild-type cells, their adhesion does not lead to tyrosine phosphorylation of molecules activated by adhesion, including PYK2, p130(Cas), paxillin, and PLC-gamma. However, in response to M-CSF, Src(-/-) pOCs spread and migrate on Vn in an alpha(v)beta(3)-dependent manner. Involvement of PLC-gamma activation is suggested by using a PLC inhibitor, U73122, which blocks both adhesion- and M-CSF-mediated cell spreading. Furthermore, in Src(-/-) pOCs M-CSF, together with filamentous actin, causes recruitment of beta(3) integrin and PLC-gamma to adhesion contacts and induces stable association of beta(3) integrin with PLC-gamma, phosphatidylinositol 3-kinase, and PYK2. Moreover, direct interaction of PYK2 and PLC-gamma can be induced by either adhesion or M-CSF, suggesting that this interaction may enable the formation of integrin-associated complexes. Furthermore, this study suggests that in pOCs PLC-gamma is a common downstream mediator for adhesion and growth factor signals. M-CSF-initiated signaling modulates the alpha(v)beta(3) integrin-mediated cytoskeletal reorganization in prefusion osteoclasts in the absence of c-Src, possibly via PLC-gamma.


Assuntos
Isoenzimas/metabolismo , Fator Estimulador de Colônias de Macrófagos/fisiologia , Osteoclastos/fisiologia , Proteínas , Receptores de Vitronectina/fisiologia , Transdução de Sinais/fisiologia , Fosfolipases Tipo C/metabolismo , Androstadienos/farmacologia , Animais , Adesão Celular/fisiologia , Fusão Celular , Células Cultivadas , Proteína Substrato Associada a Crk , Proteínas do Citoesqueleto/metabolismo , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Quinase 2 de Adesão Focal , Fator Estimulador de Colônias de Macrófagos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Paxilina , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipase C gama , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Pirrolidinonas/farmacologia , Proteína p130 Retinoblastoma-Like , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Vitronectina , Wortmanina , Quinases da Família src/deficiência , Quinases da Família src/genética , Quinases da Família src/metabolismo
13.
Science ; 230(4732): 1398-401, 1985 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-3906897

RESUMO

In certain strains of mice, bone marrow grafts from parental donors fail to grow in first-generation hybrid mice. This "hybrid resistance" of nonsensitized F1 hybrid mice to the engraftment of parental hematopoietic transplants contradicts the classical laws of transplantation and is dependent on a radioresistant but immunogenetically specific effector mechanism. Studies in a new in vitro model reveal that committed hematopoietic precursors of parental origin can be inactivated by direct contact with natural killer-like splenic effectors from F1 mice. The reaction requires genetically restricted recognition, since only parental competitors syngeneic to the target bone marrow cells partially reversed this inactivation. Models of this type may be useful in studying the possible role of natural resistance in bone marrow transplantation in humans.


Assuntos
Transplante de Medula Óssea , Histocompatibilidade , Células Matadoras Naturais/imunologia , Animais , Medula Óssea/imunologia , Ensaio de Unidades Formadoras de Colônias , Cruzamentos Genéticos , Células-Tronco Hematopoéticas/imunologia , Hibridização Genética , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Modelos Biológicos
14.
Artigo em Inglês | MEDLINE | ID: mdl-19842407

RESUMO

The medical records of Japanese patients with measles, age 15 to 39 years old, were analyzed for febrile period in 200 patients and maximum body temperature in 211 patients. The febrile periods by age group were as follows: 7.7 +/- 1.4 days, 7.8 +/- 1.7 days, 8.1 +/- 1.7 days, 8.1 +/- 2.4 days and 7.5 +/- 1.4 days in 15-19, 20-24, 25-29, 30-34 and 35-39 year-olds, respectively. No significant differences in febrile periods were identified among the different age groups. A maximum body temperature over 40 degrees C was seen in 61, 58, 59, 50 and 33% of the 15-19, 20-24, 25-29, 30-34 and 35-39 year-olds, respectively. The results of our study indicate age is not a determining factor for febrile period, but maximum body temperature may be lower in older than in younger patients with measles.


Assuntos
Febre/etiologia , Sarampo/complicações , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
15.
J Clin Invest ; 102(5): 881-92, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9727056

RESUMO

Osteoclast activation is initiated by adhesion to the bone surface, followed by cytoskeletal rearrangement, the formation of the sealing zone, and a polarized ruffled membrane. This study shows that PYK2/CAKbeta/RAFTK, a cytoplasmic kinase related to the focal adhesion kinase, is highly expressed in rat osteoclasts in vivo. Using murine osteoclast-like cells (OCLs) or their mononuclear precursors (pOCs), generated in a coculture of bone marrow and osteoblastic MB1.8 cells, we show: (a) tyrosine phosphorylation of PYK2 upon ligation of beta3 integrins or adhesion of pOCs to serum, vitronectin, osteopontin, or fibronectin but not to laminin or collagen; (b) coimmunoprecipitation of PYK2 and c-Src from OCLs; (c) PYK2 binding to the SH2 domains of Src; (d) marked reduction in tyrosine phosphorylation and kinase activity of PYK2 in OCLs derived from Src (-/-) mice, which do not form actin rings and do not resorb bone; (e) PYK2 phosphorylation by exogeneous c-Src; (f) translocation of PYK2 to the Triton X-100 insoluble cytoskeletal fraction upon adhesion; (g) localization of PYK2 in podosomes and the ring-like structures in OCLs plated on glass and in the sealing zone in OCLs plated on bone; and (h) activation of PYK2, in the presence of MB1.8 cells, parallels the formation of sealing zones and pit resorption in vitro and is reduced by echistatin or calcitonin and cytochalasin D. Taken together, these findings suggest that Src-dependent tyrosine phosphorylation of PYK2 is involved in the adhesion-induced formation of the sealing zone, required for osteoclastic bone resorption.


Assuntos
Adesão Celular/fisiologia , Osteoclastos/enzimologia , Proteínas Tirosina Quinases/fisiologia , Receptores de Vitronectina/metabolismo , Quinases da Família src/metabolismo , Animais , Células da Medula Óssea/metabolismo , Reabsorção Óssea/metabolismo , Moléculas de Adesão Celular/fisiologia , Linhagem Celular , Colecalciferol/farmacologia , Técnicas de Cocultura , Ativação Enzimática/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Quinase 1 de Adesão Focal , Quinase 2 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Regulação da Expressão Gênica/genética , Imuno-Histoquímica , Camundongos , Fosforilação , RNA Mensageiro/metabolismo , Tirosina/metabolismo , Domínios de Homologia de src/fisiologia
16.
Sci Rep ; 7(1): 4589, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28676703

RESUMO

A quantum critical point (QCP) is currently being conjectured for the BaFe2(As1-x P x )2 system at the critical value x c ≈ 0.3. In the proximity of a QCP, all thermodynamic and transport properties are expected to scale with a single characteristic energy, given by the quantum fluctuations. Such a universal behavior has not, however, been found in the superconducting upper critical field H c2. Here we report H c2 data for epitaxial thin films extracted from the electrical resistance measured in very high magnetic fields up to 67 Tesla. Using a multi-band analysis we find that H c2 is sensitive to the QCP, implying a significant charge carrier effective mass enhancement at the doping-induced QCP that is essentially band-dependent. Our results point to two qualitatively different groups of electrons in BaFe2(As1-x P x )2. The first one (possibly associated to hot spots or whole Fermi sheets) has a strong mass enhancement at the QCP, and the second one is insensitive to the QCP. The observed duality could also be present in many other quantum critical systems.

17.
J Endocrinol ; 189(3): 541-54, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16731785

RESUMO

In vertebrates, sperm development and maturation are directly regulated by gonadal steroid hormone secretion. The relationships among the expression of genes encoding steroidogenic proteins and receptors for gonadotropins, and testicular steroid production have not yet been comprehensively determined in male teleosts. In this study, the changes in levels of mRNAs encoding follicle-stimulating hormone (FSH) receptor, luteinizing hormone (LH) receptor, steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage, 3beta-hydroxysteroid dehydrogenase/delta5-4-isomerase, cytochrome P450 17alpha-hydroxylase/17,20-lyase, cytochrome P450 11beta-hydroxylase, 11beta-hydroxysteroid dehydrogenase and 20beta-hydroxysteroid dehydrogenase were determined by real-time, quantitative PCR assays and related to changes in serum steroid levels throughout the reproductive cycle in male rainbow trout. Serum 11-ketotestosterone and 17alpha,20beta-dihydroxy-4-pregnen-3-one levels were measured by RIA. Although the pattern of change in the mRNA levels for the enzymes was variable, the increases in steroidogenic enzyme mRNAs started prior to a significant increase of serum steroid levels. The patterns of transcript levels of FSH and LH receptors suggest that changes in StAR and steroidogenic enzyme transcripts are largely mediated by the FSH receptor during early and mid-spermatogenesis and by the LH receptor during late spermatogenesis and spermiation. Levels of StAR (10-fold) and P450 17alpha-hydroxylase/17,20-lyase (sevenfold) transcripts changed with the greatest magnitude and were closely related to the changes in serum steroids, suggesting that changes in StAR and P450 17alpha-hydroxylase/17,20-lyase abundance are likely to be the major influences on overall steroidogenic output during the reproductive cycle in male rainbow trout.


Assuntos
Oncorhynchus mykiss/metabolismo , Fosfoproteínas/genética , Receptores Acoplados a Proteínas G/genética , Espermatogênese/fisiologia , Esteroide 17-alfa-Hidroxilase/genética , Testículo/metabolismo , 17-Hidroxiesteroide Desidrogenases/genética , 20-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/genética , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Sistema Enzimático do Citocromo P-450/genética , Expressão Gênica , Masculino , Oxigenases de Função Mista/genética , RNA Mensageiro/análise , RNA Ribossômico 18S/análise , Receptores do FSH/genética , Receptores do LH/genética , Proteínas Ribossômicas/genética , Esteroide 11-beta-Hidroxilase/genética
18.
Circ Res ; 88(6): 578-86, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11282891

RESUMO

Although immunoapheresis removing autoantibodies against the second extracellular domain of beta(1)-adrenergic receptors (ARs) improves cardiac function in patients with cardiomyopathy, the underlying mechanisms have not been defined. We examined the role of autoimmunity against the domain in the development of cardiac dysfunction in vivo. Japanese white rabbits were immunized with a synthetic peptide corresponding to the second extracellular loop of beta(1)-AR once a month with (beta+biso rabbits, n=10) or without (beta rabbits, n=13) bisoprolol treatment (2 mg/kg per day). Control rabbits received vehicle without bisoprolol treatment (n=13). Autoantibodies of IgG isotype against the domain were persistently detected in beta and beta+biso rabbits. Purified IgG from sera of beta and beta+biso rabbits increased cAMP production in a rabbit cardiac membrane preparation, which was blocked by bisoprolol. At 3 months, beta-AR uncoupling with increased G protein-coupled receptor kinase 5 (GRK5) expression was found in beta rabbits. At 6 months, left ventricular hypertrophy was noted with hemodynamic derangements in beta rabbits. This was accompanied by decreased beta(1)-AR density and increased inhibitory G protein and GRK5 expression, which were related to marked decrease in membrane cAMP production. These changes in beta rabbits at 6 months were prevented in beta+biso rabbits. There was no difference in the plasma norepinephrine concentration in the 3 groups over the observation period. Thus, autoimmunity against the second extracellular loop of beta(1)-ARs induced profound beta-AR desensitization and myocardial hypertrophy in vivo, associated with cardiac dysfunction. Sustained sympathomimetic-like actions of autoantibodies against the domain may be partly responsible for these changes.


Assuntos
Cardiomegalia/fisiopatologia , Fragmentos de Peptídeos/imunologia , Receptores Adrenérgicos beta 1/imunologia , Agonistas Adrenérgicos beta/farmacologia , Sequência de Aminoácidos , Animais , Ligação Competitiva/genética , Western Blotting , Cardiomegalia/imunologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ecocardiografia , Quinase 5 de Receptor Acoplado a Proteína G , Proteínas de Ligação ao GTP/metabolismo , Ventrículos do Coração/imunologia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Imunoglobulina G/administração & dosagem , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Isoproterenol/farmacologia , Masculino , Membranas/efeitos dos fármacos , Membranas/metabolismo , Dados de Sequência Molecular , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/sangue , Proteínas Serina-Treonina Quinases/metabolismo , Coelhos , Ensaio Radioligante , Receptores Adrenérgicos beta 1/química , Quinases de Receptores Adrenérgicos beta
19.
Cell Mol Biol (Noisy-le-grand) ; 52(3): 19-23, 2006 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-17535750

RESUMO

Calcitonin is a calcium-regulating peptide hormone that acts directly on osteoclasts and suppresses their function. In this review we will focus on the downstream signaling pathways of calcitonin receptor regulating cytoskeletal organization of osteoclasts. We will also introduce the clinical application of the hormone for metabolic bone diseases.


Assuntos
Reabsorção Óssea/metabolismo , Calcitonina/metabolismo , Citoesqueleto/fisiologia , Osteoclastos/fisiologia , Receptores da Calcitonina/metabolismo , Transdução de Sinais/fisiologia , Animais
20.
J Natl Cancer Inst ; 80(10): 728-34, 1988 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-2455061

RESUMO

Lymphocytes from mediastinal lymph nodes of 9 patients with primary lung cancer were fused with murine myeloma cells (P3U1). One of the clones (4G12) was stable for secretion (10 micrograms/ml) of human IgM lambda for 24 months. The antigen detected by 4G12 was sensitive to both trypsin and periodic acid-Schiff treatment. It immunoprecipitated a glycoprotein with an Mr of 65,000 upon analysis in sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reduced conditions. Immunohistochemical staining demonstrated that 4G12 possessed a high reactivity to squamous cell carcinomas of the lung (29 of 29) and also reacted with other lung carcinomas [adenocarcinomas (14 of 20) and large cell carcinomas (3 of 8)] and with some nonpulmonary malignant tumors (15 of 56). However, it did not react with small cell carcinomas of the lung. No benign tumors (0 of 26) so far tested have been positive. 4G12 did not react with most of the normal tissues; an exception was that it was weakly reactive on the glandular cells of the trachea and bronchi and on the proximal tubular cells of the kidneys. Thus 4G12 showed a broad reactivity to malignant tumors (68% of lung carcinomas, 27% of nonpulmonary carcinomas, and 0% of benign tumors). The reactivity of 4G12 on tissues from squamous cell carcinomas of the lung indicated that the expression of the antigenic determinant was much more in the well-differentiated grade than in the poorly differentiated grade. Thus the antigen detected by 4G12 appears to be related to tumor differentiation. Moreover, fluorescence-activated cell sorter analysis demonstrated that the expression of the antigen epitope depended on the cell cycle (G2-M). These data suggest that the 4G12 monoclonal antibody detects a new tumor-associated antigen that is recognized by the human immune system.


Assuntos
Anticorpos Monoclonais/imunologia , Neoplasias/imunologia , Adenocarcinoma/imunologia , Anticorpos Monoclonais/análise , Antígenos de Diferenciação , Carcinoma de Células Escamosas/imunologia , Ciclo Celular , Separação Celular/métodos , Epitopos , Imunofluorescência , Humanos , Hibridomas/metabolismo , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/imunologia
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