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1.
Proc Natl Acad Sci U S A ; 120(7): e2208871120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745779

RESUMO

Studies have shown that the use of languages which grammatically associate the future and the present tends to correlate with more future-oriented behavior. We take an experimental approach to go beyond correlation. We asked bilingual research participants, people fluent in two languages (12 language pairs) which differ in the way they encode time, to make a set of future-oriented economic decisions. We find that participants addressed in a language in which the present and the future are marked more distinctly tended to value future events less than participants addressed in a language in which the present and the future are similarly marked. In an additional experiment, bilingual research participants (seven language pairs) were asked to choose whether they wish to complete a more enjoyable task first or later (delayed gratification). When addressed in a language in which the present and the future are marked more distinctly, participants tended to prefer immediate gratification more than when addressed in a language in which the present and the future are marked less distinctly. We shed light on the mechanism in a within-person experiment in which bilingual research participants (nine language pairs) were asked to spatially mark the distance between the present and the future. When participants were addressed in a language in which the present and the future are marked more distinctly, they tended to express more precise temporal beliefs compared with when addressed in a language in which the present and the future are marked less distinctly.


Assuntos
Multilinguismo , Humanos , Idioma , Previsões
2.
Harefuah ; 158(3): 168-172, 2019 Mar.
Artigo em Hebraico | MEDLINE | ID: mdl-30916503

RESUMO

INTRODUCTION: Light transmission aggregometry (LTA) is the most commonly used test for the diagnosis of platelet function disorders, but requires large amounts of blood samples and normal platelet count. OBJECTIVES: To compare flow cytometric (FC) platelet function testing to standard LTA in the general population, in patients treated with anti-platelets drugs and in term and preterm neonates. METHODS: Platelet function was assessed with LTA and FC using PAC1 binding and p-selectin expression, as platelet activation markers, in response to agonist activation. A comparison between LTA and FC was performed in a Clopidogrel treated patient, before and after (24 and 72 hours) loading the drug. The platelet activation markers PAC1 and p-selectin, were compared in umbilical cord blood samples of in-term and preterm neonates. RESULTS: ADP-induced platelet aggregation was comparable to p-selectin expression assayed by FC (r=0.79-0.86) as measured before and after Clopidogrel loading. Both tests showed good response to Clopidogrel in 72 hours but not in 24 hours after its loading. Preterm cord blood platelets showed decreased ADP-induced activation in both activation markers: PAC1 and p-selectin, but only p-selectin reached statistical significance. We identified possible platelet activation markers in response to commonly used agonists' stimulation for FC analysis. CONCLUSIONS: FC analysis of platelet function has added value in the diagnosis of impaired platelet function and anti-platelet drug response. Using FC enables us to test platelet function in minimal blood volume and regardless of platelet count. Identification of the unique activation marker for each agonist is prerequisite for FC analysis of platelet function.


Assuntos
Plaquetas , Citometria de Fluxo , Agregação Plaquetária , Difosfato de Adenosina , Humanos , Inibidores da Agregação Plaquetária , Ticlopidina
4.
Blood Cells Mol Dis ; 55(2): 180-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25564295

RESUMO

Gaucher disease (GD) is characterized by glucocerebroside (GC) accumulation due to defective activity of the glucocerebrosidase (GlcCerase) enzyme. Monocytes and macrophages exhibit the highest GlcCerase activity and are most prominently affected by GC engorgement. As GD patients tend to exert various immune system-related changes, this study was designed to investigate potential effects of monocyte dysfunction on these alterations. Monocytes were isolated from peripheral blood mononuclear cells (PBMCs) of untreated GD patients and healthy volunteers. Monocyte migration capacity towards SDF1α was assessed. The GD patients exhibited reduced numbers of monocytes and decreased capability of SDF1α-dependent monocyte migration. Evaluation of CXCR4, the SDF1α receptor, revealed reduced expression of surface CXCR4 on GD-derived monocytes, despite similar CXCR4 mRNA transcript levels in the monocytes of healthy volunteers and GD patients. Reduction of surface CXCR4 was accompanied by increased intracellular CXCR4 levels in patient monocytes. This elevated intracellular CXCR4 might reflect significantly increased SDF1α concentrations characterizing patients' serum and the lysosomal impairment of GD, resulting in decreased degradation of CXCR4. Different distributions of CXCR4 expression observed in the two groups explain impaired SDF1α-dependent monocyte migration. Reduced numbers and impaired migration capacity of GD-derived monocytes could contribute to abnormal inflammation and GD-associated immune alterations seen in these patients.


Assuntos
Quimiotaxia de Leucócito/imunologia , Doença de Gaucher/imunologia , Monócitos/imunologia , Antígenos de Superfície/metabolismo , Estudos de Casos e Controles , Quimiocina CXCL12/metabolismo , Doença de Gaucher/sangue , Doença de Gaucher/genética , Doença de Gaucher/metabolismo , Expressão Gênica , Humanos , Imunofenotipagem , Contagem de Leucócitos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Monócitos/metabolismo , Ligação Proteica , Transporte Proteico , Receptores CXCR4/genética , Receptores CXCR4/metabolismo
6.
Brain Behav ; 14(3): e3451, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468457

RESUMO

INTRODUCTION: During the COVID-19 pandemic, an influx of adolescents presented worldwide with acute onset of functional tic-like behaviors (FTLBs). Our goal was to evaluate psychosocial factors around onset, to elucidate outcomes after pandemic isolation protocols were lifted, and to examine therapy and medication management. METHODS: A retrospective review was performed of 56 patients ages 10-18 years with new-onset FTLBs seen at Boston Children's Hospital beginning in March 2020. Demographic factors, medical history, and treatment were evaluated. Patient outcomes were determined retrospectively based on the Clinical Global Impression Improvement (CGI-I) and Severity (CGI-S) scales from follow-up visits. CGI-I scores assessed the progression of FTLBs; CGI-S assessed overall function. RESULTS: Ninety-six percent of patients were female-assigned at birth with high rates of comorbid anxiety (93%) and depression (71%). Forty-five percent were gender-diverse. Based on scales that assessed FTLBs (CGI-I) and overall functioning (CGI-S), up to 79% of patients improved independent of comorbid diagnosis or treatment. Evidence-based tic-specific treatments were not more effective than other treatments. A subset of patients had improvement in their FTLBs but not in their general functioning and continued to have other psychosomatic presentations. CONCLUSION: While many patients' FTLBs improved, it is critical to remain alert to patients' overall function and to assess for other functional neurological disorders and mental health concerns. The tendency of FTLBs to improve in this population, independent of treatment, highlights the unique pathophysiology of FTLBs. Future research on contributing psychosocial factors and specific treatment protocols will allow optimal support for these patients.


Assuntos
COVID-19 , Mídias Sociais , Tiques , Síndrome de Tourette , Criança , Adolescente , Recém-Nascido , Humanos , Feminino , Masculino , Tiques/tratamento farmacológico , Seguimentos , Estudos Retrospectivos , Pandemias
7.
Cancer Immunol Immunother ; 61(8): 1233-41, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22249775

RESUMO

BACKGROUND: Rituximab, an anti-CD20 monoclonal antibody, is reported to increase the T-cell-dependent infection risk. The current study was designed to investigate whether rituximab interferes with T-cell activation. PATIENTS AND METHODS: Patients with non-Hodgkin lymphoma receiving 4-6 courses of 375 mg/m(2) rituximab underwent detailed assessment of T-cell activation pre- and post-rituximab. A similar analysis assessed the in vitro effect of rituximab on T-cell activation in response to allogeneic dendritic cells (allo-DCs) and other stimuli. RESULTS: Patients receiving rituximab exhibited a significant decline in IL-2 and IFN-γ levels in peripheral blood, most prominent after repeated rituximab courses. Evaluation at 3 months after rituximab therapy showed restoration of inflammatory cytokine production. Similarly, in vitro stimulation of peripheral blood mononuclear cells in the presence of rituximab resulted in a significant decrease in T-cell activation markers, inflammatory cytokine production and proliferative capacity. These effects were also observed using B-cell-depleted T cells (CD3(+)CD25(-)CD19(-)) and were accompanied with disappearance of CD3(+)CD20(dim) T-cell population. CONCLUSION: Rituximab administration results in transient, dose-dependent T-cell inactivation. This effect is obtained even in B-cell absence and may increase the infection risk.


Assuntos
Anticorpos Monoclonais Murinos/efeitos adversos , Antineoplásicos/efeitos adversos , Ativação Linfocitária/efeitos dos fármacos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/imunologia , Linfócitos T/efeitos dos fármacos , Adulto , Idoso de 80 Anos ou mais , Separação Celular , Citocinas/biossíntese , Feminino , Citometria de Fluxo , Humanos , Ativação Linfocitária/imunologia , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-Idade , Rituximab , Linfócitos T/imunologia
8.
Am J Hematol ; 87(9): 875-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22847303

RESUMO

The use of allogeneic stem cell transplantation (SCT) for chronic myeloid leukemia (CML) was almost abandoned in recent years for very effective targeted therapy with tyrosine kinase inhibitors (TKIs). However, approximately one third of patients still need another treatment including SCT. 38 consecutive CML patients were treated (most in preimatinib era) with allogeneic SCT, using partial T cell depletion (TCD) and preemptive donor lymphocyte infusion (DLI), without post-transplant graft-versus-host disease (GvHD) prophylaxis. Conditioning included busulfan, cyclophosphamide, antithymocytic globulin, and fludarabine followed by donor stem cell transfusion. With a median follow up of 90.5 months (1-134), 32 patients are alive. 97% engrafted. 5-year leukemia free survival (LFS) and overall survival (OS) were 78.95% and 84.2%, respectively. All patients are in major molecular remission and 78% in complete molecular remission. Transplant-related mortality (TRM) was 13%. Twenty-four patients received DLI for residual disease. Acute GvHD, mostly Grades I-II, occurred in 18% of patients post-transplant and in 24% of patients receiving DLI. In conclusion, the risk-adapted approach using only partial TCD and preemptive escalated dose of DLI precluded the need for immunosuppressive medications and reduced the risk of significant GvHD without compromising engraftment and long-term disease control. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Depleção Linfocítica , Transfusão de Linfócitos , Transplante de Células-Tronco de Sangue Periférico/métodos , Condicionamento Pré-Transplante/métodos , Adulto , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Depleção Linfocítica/métodos , Transfusão de Linfócitos/métodos , Masculino , Pessoa de Meia-Idade , Risco , Linfócitos T/efeitos dos fármacos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
9.
Front Psychiatry ; 13: 929526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966462

RESUMO

Obsessive compulsive disorder (OCD) and chronic tic disorders (CTD) including Tourette Syndrome (TS) are often comorbid conditions. While some patients present with distinct symptoms of CTD and/or OCD, a subset of patients demonstrate a unique overlap of symptoms, known as Tourettic OCD (TOCD), in which tics, compulsions, and their preceding premonitory urges are overlapping and tightly intertwined. The specific behaviors seen in TOCD are typically complex tic-like behaviors although with a compulsive and partially anxious nature reminiscent of OCD. TOCD is not classified within the Diagnostic and Statistical Manual of Mental Disorders fifth edition (DSM-5) as an independent diagnostic entity, but mounting evidence suggests that TOCD is an intermediate neuropsychiatric disorder distinct from either TS or OCD alone and as such represents a unique phenomenology. In this review of TOCD we discuss clinical, genetic, environmental, neurodevelopmental, and neurocircuit-based research to better characterize our current understanding of this disorder. TOCD is characterized by earlier age of onset, male predominance, and specific symptom clusters such as lower tendency toward compulsions related to checking, cleaning, and reassurance seeking and higher tendency toward compulsions such as rubbing, tapping, or touching associated with symmetry concerns or thoughts of exactness. Functional magnetic resonance imaging (fMRI) imaging suggests that TOCD symptoms may arise from involvement of an intermediate neurocircuitry distinct from classic OCD or classic CTD. Small cumulative contributions from multiple genetic loci have been implicated, as have environmental factors such as infection and perinatal trauma. In addition, this review addresses the treatment of TOCD which is especially complex and often treatment resistant and requires pharmacology and behavioral therapy in multiple modalities. Given the distressing impact of TOCD on patients' functioning, the goal of this review is to raise awareness of this distinct entity toward the goal of improving standards of care.

10.
JAMA Health Forum ; 3(5): e221012, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35977256

RESUMO

This cross-sectional study examines the prevalence and characteristics of real estate investment trust-owned health care properties in the US health care sector.


Assuntos
Atenção à Saúde , Investimentos em Saúde , Propriedade , Estudos Transversais , Estados Unidos
11.
Proc Natl Acad Sci U S A ; 105(25): 8499-506, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18574143

RESUMO

The counterclockwise coiling of the intestines is initiated by a leftward tilt of the primitive gut tube, imparted by left-right asymmetries in the architecture of the dorsal mesentery. In silico analysis suggests that this is achieved by synergistic changes in its epithelium and mesenchyme. Within the mesenchymal compartment, cells are more densely packed on the left than on the right. In silico results indicate that this property can result from asymmetries in both extracellular matrix (ECM) and cell:cell adhesion. We find that the dorsal mesentery ECM is indeed left-right asymmetric and moreover that the adhesion molecule N-cadherin is expressed exclusively on the left side. These asymmetries are regulated by the asymmetrically expressed transcription factors Pitx2 and Isl1. Functional studies demonstrate that N-cadherin acts upstream of the changes in the ECM and is both necessary and sufficient to explain the asymmetric packing of the mesenchymal cells.


Assuntos
Matriz Extracelular/metabolismo , Intestinos/embriologia , Intestinos/fisiologia , Animais , Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular , Embrião de Galinha , Galinhas , Epitélio/metabolismo , Mesoderma/citologia , Mesoderma/metabolismo
12.
NPJ Sci Learn ; 6(1): 9, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824344

RESUMO

Research suggests that gendered languages are associated with gender inequality. However, as languages are embedded in cultures, evidence for causal effects are harder to provide. We contribute to this ongoing debate by exploring the relationship between gendered languages and the gender gap in mathematics achievements. We provide evidence for causality by exploiting the prominent (but not exclusive) practice in gendered languages of using masculine generics to address women. In an experiment on a large representative sample of the Hebrew-speaking adult population in Israel, we show that addressing women in the feminine, compared to addressing them in the masculine, reduces the gender gap in mathematics achievements by a third. These effects are stronger among participants who acquired the Hebrew language early in childhood rather than later in life, suggesting that it is the extent of language proficiency that generates one's sensitivity to being addressed in the masculine or in the feminine. Moreover, when women are addressed in the masculine, their efforts (in terms of time spent on the maths test) decrease and they report feeling that "science is for men" more than when addressed in the feminine. We supplement the analysis with two experiments that explore the roles of general and task-specific stereotypes in generating these effects.

13.
Eur J Immunol ; 39(10): 2703-15, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19634189

RESUMO

Human induced CD4(+)CD25(+) T cells have been shown to express FOXP3, similar to naturally occurring Treg cells (nTreg). However, the suppressive capacity of these cells is still under debate. The current study was designed to investigate functional characteristics of CD25(+)FOXP3(+) derived from CD25(-) T cells. Stimulation of CD25(-) PBMC with allogeneic PBMC resulted in production of CD4(+)CD25(high) T cells. This process was more rapid and prominent when highly mature DC were used for stimulation. The resultant CD4(+)CD25(high) population concurrently exhibited regulatory markers FOXP3, CTLA-4, GITR, and inflammatory cytokines IL-2 and IFN-gamma. These human-induced FOXP3(+)IFN-gamma(+) T cells were shown, for the first time, to markedly inhibit alloreactive T-cell expansion, similar to nTreg. However, in contrast to nTreg, the induced CD4(+)CD25(+)FOXP3(+) cells did not suppress proliferation against a third party donor stimulus or CMV. This suggested that the cell population possessed a more selective suppressive capacity targeted against the original stimulus only. The induced human CD4(+)CD25(+)FOXP3(+) subset derived from CD25(-) T cells, while expressing inflammatory cytokines, exhibits a suppressive cell contact-dependent effect, restricted against T cells responding to the original stimulus. Such unique properties suggest that these cells are potentially ideal for the use as post-transplant GVH disease prophylaxis.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Tolerância Imunológica/imunologia , Interferon gama/metabolismo , Linfócitos T Reguladores/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Antígenos CD/metabolismo , Antígeno CTLA-4 , Comunicação Celular/imunologia , Proliferação de Células , Células Dendríticas/imunologia , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Humanos , Tolerância Imunológica/efeitos dos fármacos , Interferon gama/imunologia , Interleucina-10/farmacologia , Interleucina-2/imunologia , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/imunologia , Teste de Cultura Mista de Linfócitos , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Proteínas com Domínio T/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia
14.
PLoS One ; 15(7): e0235438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706822

RESUMO

Are darker-skinned workers discriminated against in the labor market? Studies using survey data have shown that darker skin tone is associated with increased labor market disadvantages. However, it is hard to refute the possibility that other factors correlated with skin tones might affect employment outcomes. To overcome this inherent limitation, we use a natural experiment: we utilize changes in one's own skin tone, generated by exposure to the sun, to explore the effect of skin tone on the tendency to be employed. We find that those people whose skin tone becomes darker by exposure to the sun (but not others) are less likely to be employed when the UV radiation in the previous three weeks in the area in which they reside is greater. These within-person findings hold even when controlling for the week, the year, the region, demographic characteristics and the occupation and industry one is employed in.


Assuntos
Emprego/ética , Racismo/ética , Pigmentação da Pele , Discriminação Social/ética , Adulto , Emprego/psicologia , Feminino , Humanos , Masculino , Racismo/psicologia , Discriminação Social/psicologia , Inquéritos e Questionários , Raios Ultravioleta
15.
Bone Marrow Transplant ; 55(7): 1305-1316, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32433499

RESUMO

Graft versus host disease (GvHD) remains a limiting factor for successful hematopoietic stem cell transplantation (HSCT). T cells and antigen-presenting cells (APCs) are major components of the hematopoietic G-CSF mobilized peripheral blood cell (MPBC) graft. Here we show that a short incubation (2 h) of MPBCs with hexameric Fas ligand (FasL) selectively induces apoptosis of specific donor T cell subsets and APCs but not of CD34+ cells. FasL treatment preferentially induces apoptosis in mature T cell subsets which express high levels of Fas (CD95), such as T stem cell memory, T central memory, and T effector memory cells, as well as TH1 and TH17 cells. Anti-CD3/CD28 stimulated T cells derived from FasL-treated-MPBCs express lower levels of CD25 and secrete lower levels of IFN-γ as compared to control cells not treated with FasL. FasL treatment also induces apoptosis of transitional, naïve, memory and plasmablastoid B cells leading to a reduction in their numbers in the graft and following engraftment in transplanted mice. Most importantly, ex vivo treatment of MPBCs with FasL prior to transplant in conditioned NOD-scid IL2Rγnull (NSG) mice prevented GvHD while preserving graft versus leukemia (GvL) effects, and leading to robust stem cell engraftment.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Proteína Ligante Fas , Doença Enxerto-Hospedeiro/prevenção & controle , Ligantes , Camundongos , Camundongos Endogâmicos NOD , Células-Tronco
17.
Sci Adv ; 2(2): e1500599, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26989770

RESUMO

Gender inequality in contemporary U.S. society is a well-documented, widespread phenomenon. However, little is known about gender disparities in product markets. This study is the first to use actual market data to study the behavior of women and men as sellers and buyers and differences in market outcomes. We analyze a unique and large data set containing all eBay auction transactions of most popular products by private sellers between the years 2009 and 2012. Women sellers received a smaller number of bids and lower final prices than did equally qualified men sellers of the exact same product. On average, women sellers received about 80 cents for every dollar a man received when selling the identical new product and 97 cents when selling the same used product. These findings held even after controlling for the sentiments that appear in the text of the sellers' listings. Nonetheless, it is worth noting that this gap varied by the type of the product being sold. As a policy, eBay does not reveal the gender of users. We attribute the price differences to the ability of buyers to discern the gender of the seller. We present results from an experiment that shows that people accurately identify the gender of sellers on the basis of typical information provided in postings. We supplement the analysis with an additional off-eBay experiment showing that, in a controlled setting, people are willing to pay less for money-value gift cards when they are sold by women rather than men.


Assuntos
Marketing/economia , Sexismo/economia , Adulto , Feminino , Humanos , Masculino , Estados Unidos
18.
Haematologica ; 90(11): 1549-56, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16266903

RESUMO

BACKGROUND AND OBJECTIVES: The frequency of thrombotic complications is increased in patients with acute leukemia. Since coagulation processes take place on cell membranes, we hypothesized that expression of coagulation proteins on blast membrane could determine the hemostatic balance on the surface of leukemic cells and may correlate with thrombotic manifestations. DESIGN AND METHODS: Fifty-one consecutive patients with newly diagnosed acute leukemia were enrolled over an 11-month period. Twenty-five of the patients had acute myeloid leukemia (AML)-M(0-2), 11 had AML-M3, 6 had AML-M(4-5), and 9 acute lymphocytic leukemia (ALL). Peripheral blood and bone marrow were analyzed by flow-cytometry for tissue factor, protease-activated receptor 1, tissue factor pathway inhibitor, urokinase plasminogen activator receptor, and thrombomodulin. RESULTS: Regardless of the leukemia subtype, tissue factor was predominantly present on leukemic blast surfaces as compared to protease-activated receptor 1, tissue factor pathway inhibitor, urokinase plasminogen activator receptor and thrombomodulin and it was significantly elevated (mean 63+/-6%) in AML-M3 and AML-M(4-5) as compared to AML-M0(-2) and ALL (mean 37+/-4%, p<0.001). Likewise, urokinase plasminogen activator receptor expression was greater in AML-M(4-5) (49+/-11%) than in in AML- M(0-2), M3 and, ALL (mean 17+/-3%, p<0.001). Thrombotic manifestations were present in 13 out of 51 (26%) patients. The tissue factor to urokinase plasminogen activator receptor ratio was higher in patients with a thrombotic event than in patients without thrombotic events (16+/-4 vs. 6+/-2, p=0.042). INTERPRETATION AND CONCLUSIONS: This study demonstrates that tissue factor predominates on leukemic blast surface, particularly in M3 and M4-5 subtypes, while urokinase plasminogen activator receptor is increased on M4-5 blasts. The hemostatic balance on the blast surface may contribute to thrombotic manifestations in leukemic patients.


Assuntos
Hemostasia/fisiologia , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/fisiopatologia , Receptores de Superfície Celular/fisiologia , Tromboplastina/fisiologia , Trombose/metabolismo , Trombose/fisiopatologia , Adulto , Idoso , Membrana Celular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Ativador de Plasminogênio Tipo Uroquinase
20.
Thromb Haemost ; 92(4): 776-86, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15467908

RESUMO

The placenta is a highly vascularized organ with fetal and maternal blood supply. Syncytiotrophoblasts (STB), which line the placenta villous are possibly involved in local hemostatic mechanisms. The aim of this study was to evaluate the levels of tissue factor (TF) and its inhibitors, tissue factor pathway inhibitor (TFPI, TFPI-2), in STB model within hemostatic and inflammatory environments. Human primary STB cell cultures were characterized by vascular and hormonal markers. TF and TFPI mRNA expression, protein levels and activity were determined and compared to human umbilical vein endothelial cells (HUVEC). High levels of TF were demonstrated in STB cells compared to low levels in HUVEC. In contrast, STB expressed lower TFPI levels than HUVEC. LPS and TNFalpha increased the high constitutive TF in STB, whereas LPS and IL-1alpha further reduced TFPI levels. The procoagulant tendency of STB identified by us may reflect the physiological need for immediate inhibition of hemorrhage in the placental inter-villous spaces in basal and inflammatory conditions. This hemostatic balance may be critical for normal placental function and pregnancy outcome.


Assuntos
Hemostasia , Lipoproteínas/análise , Placenta/fisiologia , Tromboplastina/análise , Trofoblastos/química , Células Cultivadas , Endotélio Vascular/química , Endotélio Vascular/citologia , Humanos , Lipoproteínas/genética , Placenta/citologia , RNA Mensageiro/análise , Tromboplastina/genética , Veias Umbilicais
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