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1.
Haemophilia ; 24(2): 271-277, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29282815

RESUMO

INTRODUCTION: Cerebral microbleeds (CMBs) represent clinically silent haemorrhagic events. Cerebral microbleeds (CMBs) portend negative neurovascular and cognitive outcomes in the general population and are associated with cognitive impairment in persons with haemophilia (PWH). Prevalence, patterns, and risk factors for CMBs in PWH have not been directly compared to persons without coagulopathy. AIM: To examine prevalence, patterns, and risk factors for CMBs in PWH vs normal controls. METHODS: Adults with haemophilia A or B and haemostatically normal controls were recruited. Subjects were excluded if taking an antithrombotic agent other than low-dose aspirin (<100 mg). All subjects underwent T2*MRI of the brain; scans were reviewed independently by two neuroradiologists blinded to subject group to determine the presence of CMBs. RESULTS: We recruited 31 PWH and 32 controls. Human immunodeficiency virus (HIV) and history of hepatitis C virus (HCV) infection were more prevalent in PWH; smoking was more common among controls. Cardiovascular (CV) risk factors were similar between groups. Prevalence of CMBs was 35% in PWH and 25% in controls (P = .42). Among PWH, advanced age, history of HCV infection, and CV risk factors were associated with CMBs. Multiple and large (>5 mm) CMBs were seen only in PWH. CONCLUSIONS: Cerebral microbleeds (CMBs) are common in adults with haemophilia, but not clearly more prevalent than in haemostatically normal controls. In PWH, older age, HCV infection, CV risk factors, and the presence of an inhibitor were associated with CMBs. Large CMBs and multiple CMBs may be more prevalent in PWH than in the general population. The clinical impact of CMBs in PWH requires further study.


Assuntos
Hemorragia Cerebral/etiologia , Hemofilia A/complicações , Hemofilia B/complicações , Adulto , Hemorragia Cerebral/patologia , Estudos Transversais , Feminino , Hemofilia A/patologia , Hemofilia B/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
2.
Blood ; 118(13): 3591-602, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21821704

RESUMO

The follicular lymphoma (FL) T-cell microenvironment plays a critical role in the biology of this disease. We therefore determined the lineage, differentiation state, and functional potential of FL-infiltrating CD4(+) T-helper cells (T(H)) compared with reactive and normal lymph node (NLN) T(H) cells. Relative to NLNs, FL cells have decreased proportions of naive and central memory but increased proportions of effector memory T(H) cells. We further show differences in the distribution and anatomical localization of CXCR5(+) T(H) populations that, on the basis of transcription factor analysis, include both regulatory and follicular helper T cells. On Staphylococcus enterotoxin-B stimulation, which stimulates T cells through the T-cell receptor, requires no processing by APCs, and can overcome regulator T cell-mediated suppression, the proportion of uncommitted primed precursor cells, as well as T(H)2 and T(H)17 cells is higher in FL cells than in reactive lymph nodes or NLNs. However, the proportion of T(H)1 and polyfunctional T(H) cells (producing multiple cytokines simultaneously) is similar in FL cells and NLNs. These data suggest that, although T(H)-cell differentiation in FL is skewed compared with NLNs, FL T(H) cells should have the same intrinsic ability to elicit antitumor effector responses as NLN T(H) cells when tumor suppressive mechanisms are attenuated.


Assuntos
Diferenciação Celular/imunologia , Linfonodos/imunologia , Linfócitos do Interstício Tumoral/fisiologia , Linfoma Folicular/imunologia , Linfócitos T Auxiliares-Indutores/fisiologia , Diferenciação Celular/genética , Análise por Conglomerados , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Humanos , Memória Imunológica/genética , Memória Imunológica/fisiologia , Linfonodos/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Linfoma Folicular/patologia , Análise em Microsséries , Proteínas Proto-Oncogênicas c-bcl-6 , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo
3.
Haemophilia ; 19(4): 595-601, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23534856

RESUMO

Type 3 von Willebrand's disease (VWD) is a rare bleeding diathesis with complete or near complete deficiency of von Willebrand factor (VWF) and low factor VIII (FVIII) levels. In contrast, only FVIII is decreased in haemophilia A (HA). Both disorders are complicated by arthropathy. The purpose of this study was to further clarify the roles of FVIII and VWF: Antigen (VWF:Ag) in joint range of motion (ROM) loss over time. We compared joint ROM loss and other bleeding manifestations in 100 Type 3 VWD subjects (FVIII<5%) and 1814 moderate HA subjects (FVIII 1-5%) within the U.S. Universal Data Collection (UDC) database. High rates of bleeding were reported at baseline. During follow-up, moderate HA patients reported a joint (46% vs. 34%, P < 0.0001) or muscle bleed (27% vs. 16%, P < 0.0001) in a higher proportion of visits than VWD patients. Other bleeds, including mucosal, were reported in a greater proportion of visits among patients with Type 3 VWD than among those with HA (49% vs. 32%, P < 0.0001). Multivariate analysis revealed no difference in joint ROM loss over time in the Type 3 VWD vs. moderate HA populations. A higher FVIII level was protective in both VWD and HA (P < 0.001). Our findings support the hypothesis of primacy of the FVIII level in determining risk of joint haemorrhage, and may help target therapy in Type 3 VWD and moderate HA to prevent joint disability.


Assuntos
Hemofilia A/complicações , Hemofilia A/fisiopatologia , Articulações/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Doença de von Willebrand Tipo 3/complicações , Doença de von Willebrand Tipo 3/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Demografia , Feminino , Seguimentos , Hemofilia A/patologia , Hemorragia/complicações , Hemorragia/fisiopatologia , Humanos , Articulações/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Adulto Jovem , Doença de von Willebrand Tipo 3/patologia
4.
J Glob Health ; 13: 04141, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38033248

RESUMO

Background: Prior research has demonstrated that low- and low-middle-income countries (LLMICs) bear a higher burden of critical illness and have a higher rate of mortality from critical illness than high-income countries (HICs). There is a pressing need for improved critical care delivery in LLMICs to reduce this inequity. This systematic review aimed to characterise the range of critical care interventions and services delivered within LLMIC health care systems as reported in the literature. Methods: A search strategy using terms related to critical care in LLMICs was implemented in multiple databases. We included English language articles with human subjects describing at least one critical care intervention or service in an LLMIC setting published between 1 January 2008 and 1 January 2020. Results: A total of 1620 studies met the inclusion criteria. Among the included studies, 45% of studies reported on pediatric patients, 43% on adults, 23% on infants, 8.9% on geriatric patients and 4.2% on maternal patients. Most of the care described (94%) was delivered in-hospital, with the remainder (6.2%) taking place in out-of-hospital care settings. Overall, 49% of critical care described was delivered outside of a designated intensive care unit. Specialist physicians delivered critical care in 60% of the included studies. Additional critical care was delivered by general physicians (40%), as well as specialist physician trainees (22%), pharmacists (16%), advanced nursing or midlevel practitioners (8.9%), ambulance providers (3.3%) and respiratory therapists (3.1%). Conclusions: This review represents a comprehensive synthesis of critical care delivery in LLMIC settings. Approximately 50% of critical care interventions and services were delivered outside of a designated intensive care unit. Specialist physicians were the most common health care professionals involved in care delivery in the included studies, however generalist physicians were commonly reported to provide critical care interventions and services. This study additionally characterised the quality of the published evidence guiding critical care practice in LLMICs, demonstrating a paucity of interventional and cost-effectiveness studies. Future research is needed to understand better how to optimise critical care interventions, services, care delivery and costs in these settings. Registration: PROSPERO CRD42019146802.


Assuntos
Estado Terminal , Atenção à Saúde , Lactente , Adulto , Humanos , Criança , Idoso , Pobreza , Cuidados Críticos
5.
Eur Respir J ; 38(1): 78-88, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21071472

RESUMO

Strategies to improve pulmonary endothelial barrier function are needed to reverse the devastating effects of vascular leak in acute respiratory distress syndrome. FTY720 is a pharmaceutical analogue of the potent barrier-enhancing phospholipid sphingosine 1-phosphate (S1P). FTY720 decreases vascular permeability by an incompletely characterised mechanism that differs from S1P. Here, we describe its barrier-promoting effects on intracellular signalling and junctional assembly formation in human pulmonary endothelium. Permeability of cultured human pulmonary endothelial cells was assessed using transendothelial electrical resistance and dextran transwell assays. Junctional complex formation was assessed using membrane fractionation and immunofluorescence. Pharmacological inhibitors and small interfering (si)RNA were utilised to determine the effects of individual components on permeability. Unlike S1P, FTY720 failed to induce membrane translocation of adherens junction or tight junction proteins. ß-catenin, occludin, claudin-5 or zona occludens protein (ZO)-1/ZO-2 siRNAs did not alter FTY720-induced barrier enhancement. FTY720 induced focal adhesion kinase (FAK) phosphorylation and focal adhesion formation, with FAK siRNA partially attenuating the prolonged phase of barrier enhancement. Inhibition of Src, protein kinase (PK)A, PKG, PKC or protein phosphatase 2A failed to alter FTY720-induced barrier enhancement. FTY720 increased c-Abl tyrosine kinase activity and c-Abl siRNA attenuated peak barrier enhancement after FTY720. FTY720 enhances endothelial barrier function by a novel pathway involving c-Abl signalling.


Assuntos
Células Endoteliais/citologia , Regulação da Expressão Gênica , Pulmão/efeitos dos fármacos , Propilenoglicóis/farmacologia , Proteínas Proto-Oncogênicas c-abl/metabolismo , Esfingosina/análogos & derivados , Junções Aderentes/patologia , Células Cultivadas , Cloridrato de Fingolimode , Humanos , Inflamação , Lisofosfolipídeos/metabolismo , Permeabilidade , Fosforilação , Artéria Pulmonar/citologia , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Esfingosina/metabolismo , Esfingosina/farmacologia , Frações Subcelulares/metabolismo , Junções Íntimas/patologia
6.
J Immunol ; 183(10): 6157-66, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19864600

RESUMO

Our previous work has demonstrated that human follicular lymphoma (FL) infiltrating T cells are anergic, in part due to suppression by regulatory T cells. In this study, we identify pericellular adenosine, interacting with T cell-associated G protein-coupled A(2A/B) adenosine receptors (AR), as contributing to FL T cell hyporesponsiveness. In a subset of FL patient samples, treatment of lymph node mononuclear cells (LNMC) with specific A(2A/B) AR antagonists results in an increase in IFN-gamma or IL-2 secretion upon anti-CD3/CD28 Ab stimulation, as compared with that seen without inhibitors. In contrast, treatment with an A(1) AR antagonist had no effect on cytokine secretion. As the rate limiting step for adenosine generation from pericellular ATP is the ecto-ATPase CD39, we next show that inhibition of CD39 activity using the inhibitor ARL 67156 partially overcomes T cell hyporesponsiveness in a subset of patient samples. Phenotypic characterization of LNMC demonstrates populations of CD39-expressing CD4(+) and CD8(+) T cells, which are overrepresented in FL as compared with that seen in normal or reactive nodes, or normal peripheral blood. Thirty percent of the FL CD4(+)CD39(+) T cells coexpress CD25(high) and FOXP3 (consistent with regulatory T cells). Finally, FL or normal LNMC hydrolyze ATP in vitro, in a dose- and time-dependent fashion, with the rate of ATP consumption being associated with the degree of CD39(+) T cell infiltration. Together, these results support the finding that the ATP-ectonucleotidase-adenosine system mediates T cell anergy in a human tumor. In addition, these studies suggest that the A(2A/B) AR as well as CD39 are novel pharmacological targets for augmenting cancer immunotherapy.


Assuntos
Antígenos CD/imunologia , Apirase/imunologia , Linfócitos T CD8-Positivos/imunologia , Anergia Clonal , Linfócitos do Interstício Tumoral/imunologia , Linfoma Folicular/imunologia , Linfócitos T Reguladores/imunologia , Adenosina/imunologia , Adenosina/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/antagonistas & inibidores , Trifosfato de Adenosina/imunologia , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Antígenos CD/metabolismo , Apirase/antagonistas & inibidores , Apirase/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Linfoma Folicular/metabolismo , Fármacos Neuroprotetores/farmacologia , Pirimidinas/farmacologia , Receptores Purinérgicos P1/imunologia , Receptores Purinérgicos P1/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Triazinas/farmacologia , Triazóis/farmacologia
7.
J Exp Med ; 145(6): 1469-83, 1977 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-325168

RESUMO

M protein was extracted from type 24, group A streptococci with pepsin at pH 5.8 and was further purified by ammonium sulfate precipitation, ribonuclease digestion, ion-exchange chromatography, and isoelectric focusing. The purified pepsin extract of M (pep M) protein was shown to be free of nontype-specific immunoreactivity in (a) complement fixation tests with heterologous M antiserum, (b) skin tests in normal adult guinea pigs, and (c) passive hemagglutination tests for the presence of lipoteichoic acid sensitizing or antigenic activity. The pep M24 was highly immunogenic; two of three rabbits developed opsonic antibody titers of 1:256 and the third a titer of 1:32 6 wk after a single injection of 100-pg doses of pep M24 emulsified in complete Freund's adjuvant. The antisera lacked nontype-specific antibodies and produced single precipitin lines in agar gel diffusion tests against crude HC1 extracts of the homologous M protein. Thus, the type-specific antigenic determinant(s) of type 24 M protein appears to be separable from immunotoxic, cross-reactive antigens without loss of immunogenicity in rabbits. The mobility of pep M24 upon electrophoresis in 10 percent sodium dodecyl sulfate pelyacrylamide gel was consistent with an average mol wt of 33,500 daltons. Amino acid analysis demonstrated a predominance of alanine, followed by glutamic acid, lysine, leucine, and aspartic acid. Pep M24 contained an estimated six to seven methionine residues and approximately ten phenylalanine residues per molecule. No other aromatic amino acids were detected. Automatic Edman degradation of pep M24 yielded the sequence of the first 29 amino acids (the amino terminal amino acid being valine) of the amino terminal region of the molecule. The detection of only one new amino acid at each step of Edman degradation confirmed the homogeneity of the purified pep M24.


Assuntos
Antígenos de Bactérias , Proteínas de Bactérias/isolamento & purificação , Pepsina A , Streptococcus pyogenes/imunologia , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Proteínas de Bactérias/imunologia , Fenômenos Químicos , Química , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Cobaias , Humanos , Focalização Isoelétrica , Camundongos
8.
Eur J Clin Microbiol Infect Dis ; 29(1): 51-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19865839

RESUMO

Previous studies in our laboratory described a new group A streptococcal protective antigen (Spa) in type 18 streptococci that was distinct from the type 18 M protein. This study was undertaken to identify additional serotypes of group A streptococci that express Spa proteins. PCR techniques were used to identify and clone a new spa gene from type 36 streptococci. The 5' sequence of spa36 was highly variable compared to spa18, while the 3' sequence was conserved. Antisera against Spa36 opsonized type 36 streptococci but not type 18 streptococci, indicating that the opsonic Spa epitopes were type-specific. Antisera against the conserved carboxy-terminal half of Spa18 were used to identify Spa or Spa-like proteins expressed on the surface of 25 of 70 different serotypes of GAS. Spa proteins may represent a new family of type-specific surface antigens that function in concert with M proteins to elicit protective immune responses.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas Opsonizantes/imunologia , Fagocitose , Streptococcus pyogenes/imunologia , Animais , Antígenos de Bactérias/genética , Técnicas de Tipagem Bacteriana , Primers do DNA/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Coelhos , Análise de Sequência de DNA , Sorotipagem , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/química , Streptococcus pyogenes/classificação , Streptococcus pyogenes/genética , Análise de Sobrevida
9.
J Immunol Methods ; 341(1-2): 106-16, 2009 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-19049809

RESUMO

Human peripheral blood dendritic cells (PBDC) are a rare population comprised of several distinctive subsets. Analysis of these cells has been hindered by their low frequency. In this study, we report a novel direct ex vivo 11-color flow cytometric assay that combines subset identification with analysis of activation status and endocytic ability of three major PBDC subsets (CD1c(+)CD11c(+) "MDC1," CD141(+)CD11c(+) "MDC2," and CD303(+)CD11c(-) "PDC") within a single platform. This method eliminates the need for DC enrichment, isolation, or prolonged culture. Human peripheral blood mononuclear cells (PBMC) from healthy donors are incubated with FITC-dextran directly ex vivo, prior to cell surface staining with various markers. As expected, PBDC identified by this assay express low levels of CD40 and CD86 directly ex vivo, and significantly upregulate expression of these molecules upon stimulation with toll-like receptor ligands LPS and CpG oligonucleotides. In addition, PDC internalize FITC-labeled dextran poorly in comparison to MDC1 and MDC2 subsets. Specificity of FITC-dextran endocytosis is further verified by imaging flow cytometry. Furthermore, the combination of surface markers used in this assay reveals a previously unreported CD4(+)CD11c(+)CD303(-)CD1c(-)CD141(-) cell population. Taken together, this assay is a rapid and cost-effective method that avoids manipulation of PBDC while providing direct ex vivo high-dimensional flow cytometry data for PBDC studies.


Assuntos
Doadores de Sangue , Células Dendríticas/citologia , Células Dendríticas/imunologia , Citometria de Fluxo/métodos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Antígenos CD/imunologia , Humanos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Oligodesoxirribonucleotídeos/imunologia , Oligodesoxirribonucleotídeos/farmacologia
10.
J Pharmacol Exp Ther ; 331(1): 54-64, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19592667

RESUMO

Novel therapies are needed to address the vascular endothelial cell (EC) barrier disruption that occurs in inflammatory diseases such as acute lung injury (ALI). We previously demonstrated the potent barrier-enhancing effects of both sphingosine 1-phosphate (S1P) and the structurally similar compound FTY720 [2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol] in inflammatory lung injury. In this study, we examined the therapeutic potential of several novel FTY720 analogs to reduce vascular leak. Similar to S1P and FTY720, the (R)- and (S)-enantiomers of FTY720 phosphonate and enephosphonate analogs produce sustained EC barrier enhancement in vitro, as seen by increases in transendothelial electrical resistance (TER). In contrast, the (R)- and (S)-enantiomers of FTY720-regioisomeric analogs disrupt EC barrier integrity in a dose-dependent manner. Barrier-enhancing FTY720 analogs demonstrate a wider protective concentration range in vitro (1-50 microM) and greater potency than either S1P or FTY720. In contrast to FTY720-induced EC barrier enhancement, S1P and the FTY720 analogs dramatically increase TER within minutes in association with cortical actin ring formation. Unlike S1P, these FTY720 analogs exhibit differential phosphorylation effects without altering the intracellular calcium level. Inhibitor studies indicate that barrier enhancement by these analogs involves signaling via G(i)-coupled receptors, tyrosine kinases, and lipid rafts. Consistent with these in vitro responses, the (S)-phosphonate analog of FTY720 significantly reduces multiple indices of alveolar and vascular permeability in a lipopolysaccharide-mediated murine model of ALI (without significant alterations in leukocyte counts). These results demonstrate the capacity for FTY720 analogs to significantly decrease pulmonary vascular leakage and inflammation in vitro and in vivo.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Permeabilidade Capilar/fisiologia , Cloridrato de Fingolimode/análogos & derivados , Mediadores da Inflamação/síntese química , Mediadores da Inflamação/farmacologia , Organofosfonatos/síntese química , Organofosfonatos/farmacologia , Propilenoglicóis/síntese química , Propilenoglicóis/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Esfingosina/análogos & derivados , Animais , Linhagem Celular , Cloridrato de Fingolimode/síntese química , Cloridrato de Fingolimode/farmacologia , Humanos , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Artéria Pulmonar/patologia , Esfingosina/síntese química , Esfingosina/farmacologia
11.
J Cell Biol ; 147(4): 729-42, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10562277

RESUMO

A screen for mutants of Saccharomyces cerevisiae secretory pathway components previously yielded sec34, a mutant that accumulates numerous vesicles and fails to transport proteins from the ER to the Golgi complex at the restrictive temperature (Wuestehube, L.J., R. Duden, A. Eun, S. Hamamoto, P. Korn, R. Ram, and R. Schekman. 1996. Genetics. 142:393-406). We find that SEC34 encodes a novel protein of 93-kD, peripherally associated with membranes. The temperature-sensitive phenotype of sec34-2 is suppressed by the rab GTPase Ypt1p that functions early in the secretory pathway, or by the dominant form of the ER to Golgi complex target-SNARE (soluble N-ethylmaleimide sensitive fusion protein attachment protein receptor)-associated protein Sly1p, Sly1-20p. Weaker suppression is evident upon overexpression of genes encoding the vesicle tethering factor Uso1p or the vesicle-SNAREs Sec22p, Bet1p, or Ykt6p. This genetic suppression profile is similar to that of sec35-1, a mutant allele of a gene encoding an ER to Golgi vesicle tethering factor and, like Sec35p, Sec34p is required in vitro for vesicle tethering. sec34-2 and sec35-1 display a synthetic lethal interaction, a genetic result explained by the finding that Sec34p and Sec35p can interact by two-hybrid analysis. Fractionation of yeast cytosol indicates that Sec34p and Sec35p exist in an approximately 750-kD protein complex. Finally, we describe RUD3, a novel gene identified through a genetic screen for multicopy suppressors of a mutation in USO1, which suppresses the sec34-2 mutation as well.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Complexo de Golgi/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/fisiologia , Proteínas de Transporte Vesicular , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Transporte/isolamento & purificação , Fracionamento Celular , Clonagem Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Deleção de Genes , Genótipo , Complexo de Golgi/genética , Complexo de Golgi/ultraestrutura , Proteínas de Membrana/isolamento & purificação , Dados de Sequência Molecular , Plasmídeos , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura
12.
Cell Signal ; 19(8): 1754-64, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17475445

RESUMO

Novel therapeutic strategies are needed to reverse the loss of endothelial cell (EC) barrier integrity that occurs during inflammatory disease states such as acute lung injury. We previously demonstrated potent EC barrier augmentation in vivo and in vitro by the platelet-derived phospholipid, sphingosine 1-phosphate (S1P) via ligation of the S1P1 receptor. The S1P analogue, FTY720, similarly exerts barrier-protective vascular effects via presumed S1P1 receptor ligation. We examined the role of the S1P1 receptor in sphingolipid-mediated human lung EC barrier enhancement. Both S1P and FTY-induced sustained, dose-dependent barrier enhancement, reflected by increases in transendothelial electrical resistance (TER), which was abolished by pertussis toxin indicating Gi-coupled receptor activation. FTY-mediated increases in TER exhibited significantly delayed onset and intensity relative to the S1P response. Reduction of S1P1R expression (via siRNA) attenuated S1P-induced TER elevations whereas the TER response to FTY was unaffected. Both S1P and FTY rapidly (within 5 min) induced S1P1R accumulation in membrane lipid rafts, but only S1P stimulated S1P1R phosphorylation on threonine residues. Inhibition of PI3 kinase activity attenuated S1P-mediated TER increases but failed to alter FTY-induced TER elevation. Finally, S1P, but not FTY, induced significant myosin light chain phosphorylation and dramatic actin cytoskeletal rearrangement whereas reduced expression of the cytoskeletal effectors, Rac1 and cortactin (via siRNA), attenuated S1P-, but not FTY-induced TER elevations. These results mechanistically characterize pulmonary vascular barrier regulation by FTY720, suggesting a novel barrier-enhancing pathway for modulating vascular permeability.


Assuntos
Células Endoteliais/efeitos dos fármacos , Imunossupressores/farmacologia , Propilenoglicóis/farmacologia , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Adenoviridae/genética , Permeabilidade Capilar , Células Cultivadas , Citoesqueleto/metabolismo , Impedância Elétrica , Endotélio Vascular/citologia , Cloridrato de Fingolimode , Humanos , Pulmão/citologia , Modelos Biológicos , Fosforilação , Artéria Pulmonar/citologia , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Esfingosina/farmacologia , Treonina/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
13.
Leukemia ; 21(4): 651-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17301815

RESUMO

The homozygous mutation (677TT) in the methylenetetrahydrofolate reductase (MTHFR) gene reduces enzyme activity and alters cellular folate composition. Previous epidemiological studies reported a potential protective effect of MTHFR677C --> T against acute lymphocytic leukemia and malignant lymphoma, but the mechanism remains to be determined. We investigated the biochemical impacts of MTHFR677C --> T on cellular S-adenosyl methionine (adoMet) synthesis, global DNA methylation, and de novo purine synthesis, all of which are potential regulatory pathways involved in tumorigenesis. Metabolic fluxes of homocysteine remethylation and de novo purine synthesis were compared between Epstein-Barr virus-transformed lymphoblasts expressing MTHFR 677C and MTHFR 677T using stable isotopic tracers and GCMS. MTHFR TT genotype significantly reduced folate-dependent remethylation under folate restriction, reflecting limited methylated folates under folate restriction. Data also suggested increased formylated folate pool and increased purine synthesis when folate is adequate. The impacts of MTHFR 677T polymorphism appeared closely related to folate status, and such alterations may modulate metabolic pathways involved in cancer onset/progression. The advantage of de novo purine synthesis found in the MTHFR TT genotype may account for the protective effect of MTHFR in hematological malignancies. These transformed cells are potential models for studying the consequences of human genetic variation and cancer pathogenesis.


Assuntos
Ácido Fólico/farmacologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , S-Adenosilmetionina/biossíntese , Divisão Celular/efeitos dos fármacos , Linhagem Celular Transformada , Células Cultivadas , Metilação de DNA , Humanos , Ativação Linfocitária/fisiologia , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/enzimologia
14.
Orthop Traumatol Surg Res ; 104(6): 797-801, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29654932

RESUMO

INTRODUCTION: The glenoid track concept was used to confirm the engaging Hill-Sachs lesion (HSL) as a risk factor for recurrent instability following arthroscopic Bankart repair (ABR). However, the post-operative condition of soft tissue in vivo was not comparable to that designed in the intact condition in vitro in the original study of the glenoid track concept. Herein, the possibility of engagement may be underestimated. HYPOTHESIS: A threshold of the Hill-Sachs interval to glenoid track width ratio (H/G ratio) that is related to recurrent instability after ABR could be found, in order to adjust the original glenoid track concept. PATIENTS AND METHODS: Patients who underwent ABR with minimum 24-months follow-up were reviewed retrospectively. The primary outcome was evaluated with the recurrent instability. The H/G ratio of individual patients was used to calculate the sensitivity, specificity, and a receiver operating characteristic (ROC) curve, which aimed to establish a H/G ratio threshold related to recurrent instability after ABR. RESULTS: From June 2005 to December 2013, 160 patients with a mean age of 27.7years were enrolled. The mean follow-up period was 77.2 months. The ROC curve indicated that H/G ratio≥0.7 had the sensitivity and specificity of 0.74 and 0.71, respectively, in predicting recurrent instability. On univariate logistic regression analysis, the H/G ratio≥0.7 was a significant predictor of higher risk for recurrent instability (p<0.001). DISCUSSION: H/G ratio seems to be a reliable parameter for predicting recurrent instability. H/G ratio≥0.7 may be considered as a positive predictor for recurrent instability after ABR. LEVEL OF EVIDENCE: Level IV: retrospective diagnostic study.


Assuntos
Lesões de Bankart/diagnóstico por imagem , Lesões de Bankart/cirurgia , Cavidade Glenoide/diagnóstico por imagem , Instabilidade Articular/cirurgia , Articulação do Ombro/cirurgia , Adolescente , Adulto , Artroscopia , Lesões de Bankart/complicações , Feminino , Seguimentos , Humanos , Instabilidade Articular/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Curva ROC , Radiografia , Recidiva , Estudos Retrospectivos , Adulto Jovem
15.
J Clin Invest ; 103(9): 1261-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10225969

RESUMO

It is widely believed that the surface M protein of group A streptococci is the predominant surface protein of these organisms containing opsonic epitopes. In the present study, we identified a new surface protein, distinct from M protein, that evokes protective antibodies. A type 18 M-negative mutant was found to be both resistant to phagocytosis in human blood and virulent in mice. The wild-type strain, but not the M-negative mutant, was opsonized by antisera against purified recombinant M18 protein or a synthetic peptide copying the NH2-terminus of M18. However, antisera raised against a crude pepsin extract of the M-negative mutant opsonized both strains, indicating the presence of a protective antigen in addition to type 18 M protein. This antiserum was used to identify and purify a 24-kDa protein fragment (Spa, streptococcal protective antigen) that evoked antibodies that opsonized the M18 parent and the M-negative mutant. The results of passive mouse protection tests confirmed the presence of protective epitopes within Spa. The deduced amino acid sequence of a 636-bp 5' fragment of the spa18 gene showed no homology with sequences in GenBank. These studies reveal the presence of a new protective antigen of certain strains of group A streptococci that may prove to be an important component of vaccines to prevent streptococcal infections.


Assuntos
Antígenos de Bactérias/isolamento & purificação , Streptococcus pyogenes/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/isolamento & purificação , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Vacinas Bacterianas , Sequência de Bases , Clonagem Molecular , Reações Cruzadas , DNA Bacteriano , Soros Imunes , Camundongos , Dados de Sequência Molecular
16.
Vet J ; 224: 25-37, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28697872

RESUMO

Mammary cancer and pyometra are important health hazards associated with ovary conservation in pet dogs. Early ovariohysterectomy may reduce the incidence of these two diseases, but an estimate of the extent to which the development of mammary cancer or pyometra adversely influences overall longevity is missing. As a first step toward addressing this knowledge gap, the results of a historical cohort study of Rottweilers that lived in North America are reported. Questionnaires completed by owners and veterinarians were used to obtain lifetime health and medical information on 242 female Rottweilers, including years of lifetime ovary exposure, age at death, and cause of death. To determine the extent to which longevity was shortened in females that developed these ovary-associated diseases, age-anchored life expectancy-defined as the median number of remaining years until death for females alive at specified ages during the life course-and years of life lost, a measure of premature mortality, were estimated. Mammary carcinoma was diagnosed in 19 (7.9%) females; median age at diagnosis was 8.5 years; case fatality was 37%. Pyometra was diagnosed in 16 (6.6%) females; median age at diagnosis was 5.4 years; case fatality was 7%. Median lifetime ovary exposure for the study population was 4.3 years. Although risk for developing both diseases increased with longer ovary exposure, longer ovary exposure (≥4.3 years) was also associated with an overall longevity advantage-a 33% decrease in mortality, living 17 months longer than females with shorter ovary exposure (P=0.002). Analysis of age-anchored life expectancy showed that at no time points during the life course was the current or future diagnosis of mammary carcinoma or pyometra associated with shortened survival compared to females who never developed these conditions. This lack of longevity disadvantage is an expected result for diseases with late-onset, moderate (<50%) case fatality (mammary carcinoma) or low (<10%) case fatality (pyometra). These findings fail to support the notion that a strategy, such as elective ovariohysterectomy, implemented to reduce the incidence of mammary carcinoma and pyometra will beneficially impact overall longevity. It follows that future efforts to find and implement effective longevity-promoting interventions should look beyond reducing the incidence of a particular disease to considering trade-offs.


Assuntos
Neoplasias da Mama/veterinária , Doenças do Cão/fisiopatologia , Doenças do Cão/cirurgia , Expectativa de Vida , Ovariectomia/veterinária , Piometra/veterinária , Animais , Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/cirurgia , Cães , Feminino , Promoção da Saúde/métodos , Histerectomia/veterinária , Longevidade/fisiologia , Ovário/fisiopatologia , Piometra/fisiopatologia , Piometra/cirurgia
17.
J Immunol Methods ; 437: 13-20, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27438473

RESUMO

RATIONALE: Emerging data suggest an important role for T lymphocytes in the pathogenesis of chronic lung disease in preterm infants. Comprehensive assessment of the lymphocyte transcriptome may identify biomarkers and mechanisms of disease. METHODS: Small volume peripheral blood samples were collected from premature infants enrolled with consent in the Prematurity and Respiratory Outcomes Program (PROP), at the time of discharge from the hospital. Blood samples were collected at two sites and shipped to a central laboratory for processing. Peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll-Hypaque gradient centrifugation and separated into individual lymphocyte cell types by fluorescence-activated cell sorting. Gating strategies were optimized to ensure reproducible recovery of highly purified lymphocyte populations over a multi-year recruitment period. RNA was isolated from sorted cells and characterized by high-throughput sequencing (RNASeq). RESULTS: Blood volumes averaged 2.5ml, and sufficient PBMCs were collected from 165 of the 246 samples obtained (67%) from the 277 recruited subjects to complete sorting and RNASeq analysis on the resulting sorted cells. The number of total lymphocytes per ml of blood in the neonatal subjects was approximately 4 million/ml. Total lymphocyte frequencies recovered following sort varied widely among subjects, as did the frequency of individual lymphocyte and NK cell sub-populations. RNA yield from sorted cells varied according to cell type, but RNA of sufficient quantity and quality was recovered to enable RNASeq. SUMMARY: Our results describe a validated procedure for the generation of genome-wide expression data from isolated lymphocyte sub-populations obtained from newborn blood.


Assuntos
Perfilação da Expressão Gênica/métodos , Linfócitos/fisiologia , Separação Celular , Centrifugação com Gradiente de Concentração , Estudos de Viabilidade , Ficoll , Citometria de Fluxo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Contagem de Linfócitos , Miniaturização
18.
Mol Endocrinol ; 13(9): 1588-98, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10478848

RESUMO

Normal endocrine development and function require nuclear hormone receptor SF-1 (steroidogenic factor 1). To understand the molecular mechanism of SF-1 action, we have investigated its domain function by mutagenesis and functional analyses. Our mutant studies show that the putative AF2 (activation function 2) helix located at the C-terminal end is indispensable for gene activation. SF-1 does not have an N-terminal AF1 domain. Instead, it contains a unique FP region, composed of the Ftz-F1 box and the proline cluster, after the zinc finger motif. The FP region interacts with transcription factor IIB (TFIIB) in vitro. This interaction requires residues 178-201 of TFIIB, a domain capable of binding several transcription factors. The FP region also mediates physical interaction with c-Jun, and this interaction greatly enhances SF-1 activity. The putative SF-1 ligand, 25-hydroxycholesterol, has no effects on these bindings. In addition, the Ftz-F1 box contains a bipartite nuclear localization signal (NLS). Removing the basic residues at either end of the key nuclear localization sequence NLS2.2 abolishes the nuclear transport. Expression of mutants containing only the FP region or lacking the AF2 domain blocks wild-type SF-1 activity in cells. By contrast, the mutant having a truncated nuclear localization signal lacks this dominant negative effect. These results delineate the importance of the FP and AF2 regions in nuclear localization, protein-protein interaction, and transcriptional activation.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Sítios de Ligação/fisiologia , Células COS , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Fushi Tarazu , Regulação da Expressão Gênica , Proteínas de Homeodomínio , Humanos , Dados de Sequência Molecular , Mutação , Sinais de Localização Nuclear/genética , Ligação Proteica , Receptores Citoplasmáticos e Nucleares , Fator Esteroidogênico 1 , Fator de Transcrição TFIIB , Ativação Transcricional/genética , Ativação Transcricional/fisiologia , Células Tumorais Cultivadas
20.
Science ; 350(6256): 64-7, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26272904

RESUMO

Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption. Modeling of the spectra and photometry yields a luminosity (normalized by the luminosity of the Sun) of 1.6 to 4.0 × 10(-6) and an effective temperature of 600 to 750 kelvin. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold-start" core-accretion process that may have formed Jupiter.

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