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1.
J Exp Psychol Gen ; 153(2): 399-417, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38032615

RESUMO

Difference-education is an intervention that addresses psychological barriers that can undermine the academic performance of first-generation college students (i.e., those who have parents without 4-year degrees). Difference-education interventions improve first-generation students' performance by empowering them to navigate higher education environments more effectively. They also improve students' comfort with social group difference. However, these benefits have only been documented in higher-resourced institutions. The present research asks two questions about whether these benefits also extend to lower-resourced institutions-that is, schools with fewer resources to invest in students than the universities where prior difference-education interventions were delivered. First, is difference-education effective in improving first-generation students' academic performance in lower-resourced institutions, and does it do so by increasing empowerment? Second, does difference-education improve comfort with social group difference in lower-resourced institutions, and is it unique in its ability to do so? With students from four lower-resourced institutions, we examined these questions by comparing the results of a difference-education intervention to a control condition and social-belonging intervention. We found that while some benefits of difference-education interventions extend to lower-resourced institutions, others do not. First, like prior interventions, difference-education improves first-generation students' academic performance and comfort with social group difference. Unlike prior interventions, these effects did not persist beyond the first term and students' academic performance benefits were not explained by empowerment. We also found partial evidence that the benefits for comfort with social group difference were unique compared to a social-belonging intervention. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Instituições Acadêmicas , Estudantes , Humanos , Estudantes/psicologia , Escolaridade , Universidades
2.
J Exp Soc Psychol ; 104: 104400, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36032507

RESUMO

The Covid-19 pandemic has laid bare the vast amount of economic inequality in the U.S. Yet, has it influenced Americans' attitudes and behaviors toward equality? With a three-wave longitudinal survey, the current research provides evidence that experiencing personal harm (e.g., contracting Covid-19, losing jobs, or psychological distress) from the pandemic predicts an increase in people's attitudinal and behavioral advocacy for equality. Specifically, we find that experiencing greater personal harm in the early stages of the pandemic (i.e., May 2020) is associated with increased advocacy for equality one year later (i.e., May 2021; e.g., contacting a public official to express support for reducing inequality). Furthermore, we find that this increase in advocacy for equality is explained, in part, by people's greater endorsement of the external factors (e.g., bad luck, discrimination, etc.) that contribute to inequality. Our work provides evidence that the extent to which people experience harm from the Covid-19 pandemic predicts both their increased understanding of external sources of inequality, as well as their efforts to combat this inequality (e.g., by advocating for policies that combat structural contributors to inequality).

3.
Perm J ; 26(4): 69-77, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36446756

RESUMO

Background Sensory processing dysfunction in children has been linked to attention-deficit/hyperactivity disorder, autism, feeding disorders, and functional abdominal pain. However, little is known about sensory processing in the broader pediatric gastroenterology population. Objective To characterize frequency and type of sensory processing dysfunction seen in pediatric gastroenterology compared to a general pediatric population. Methods The Short Sensory Profile 2 was administered to the parents of children ranging 3-14 years, being seen in a pediatric gastrointestinal (GI) subspecialty clinic or general pediatric clinic. Short Sensory Profile 2 scores from age- and gender-matched groups were compared with nonparametric statistics. Results Sensory processing dysfunction was increased in children seen in the GI clinic compared to children in the general pediatric clinic. Short Sensory Profile 2 quadrant analysis revealed greatest differences in avoiding, primarily in young females of the GI population. Conclusion Children presenting to a pediatric GI clinic demonstrate greater sensory processing dysfunction compared to children in a general pediatric practice.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Gastroenteropatias , Feminino , Criança , Humanos , Prevalência , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Pais , Dor Abdominal/epidemiologia , Percepção , Gastroenteropatias/epidemiologia
4.
J Pers Soc Psychol ; 123(5): 889-908, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35254855

RESUMO

More than ever before, institutions of higher education are seeking to increase the racial and social class diversity of their student bodies. Given these efforts, the present research asks two broad questions. First, how frequently do intergroup interactions occur across the lines of race and social class, and to what extent do these interactions reflect the diversity of a setting? Second, when cross-race and cross-class interactions occur, how do individuals experience them and what consequences do they have for their outcomes in these settings? Leveraging a longitudinal design and daily diary methods, we conducted the first large study (Ninteractions = 11,460) which tracks the frequency, experience, and consequences of meaningful cross-race and cross-class interactions. We found that students reported far fewer cross-race and cross-class interactions than would occur at chance given the racial and social class diversity of their student bodies. Furthermore, students experienced less satisfaction and perspective-taking in cross-race and cross-class interactions compared to same-race and same-class interactions, respectively. Nevertheless, these cross-group interactions predicted better academic performance for underrepresented racial minority students and students from working and lower class backgrounds. They did so, in part, by increasing students' feelings of inclusion (i.e., increased belonging and reduced social identity threat). Together, these findings suggest that the mere presence of diversity is not enough to foster meaningful intergroup interactions. Furthermore, fostering intergroup interactions may be one important pathway toward reducing racial and social class disparities. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Grupos Minoritários , Identificação Social , Humanos , Classe Social , Estudantes , Universidades
5.
Sci Adv ; 4(1): e1701121, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29326974

RESUMO

The 2012 submarine eruption of Havre volcano in the Kermadec arc, New Zealand, is the largest deep-ocean eruption in history and one of very few recorded submarine eruptions involving rhyolite magma. It was recognized from a gigantic 400-km2 pumice raft seen in satellite imagery, but the complexity of this event was concealed beneath the sea surface. Mapping, observations, and sampling by submersibles have provided an exceptionally high fidelity record of the seafloor products, which included lava sourced from 14 vents at water depths of 900 to 1220 m, and fragmental deposits including giant pumice clasts up to 9 m in diameter. Most (>75%) of the total erupted volume was partitioned into the pumice raft and transported far from the volcano. The geological record on submarine volcanic edifices in volcanic arcs does not faithfully archive eruption size or magma production.

6.
Curr Opin Psychol ; 18: 123-130, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28915494

RESUMO

Social class shapes relational realities, which in turn situate and structure different selves and their associated psychological tendencies. We first briefly review how higher class contexts tend to foster independent models of self and lower class contexts tend to foster interdependent models of self. We then consider how these independent and interdependent models of self are situated in and adapted to different social class-driven relational realities. We review research demonstrating that in lower social class contexts, social networks tend to be small, dense, homogenous and strongly connected. Ties in these networks provide the bonding capital that is key for survival and that promotes the interdependence between self and other(s). In higher social class contexts, social networks tend to be large, far-reaching, diverse and loosely connected. Ties in these networks provide the bridging capital that is key for achieving personal goals and that promotes an independence of self from other. We conclude that understanding and addressing issues tied to social class and inequality requires understanding the form and function of relationships across class contexts.


Assuntos
Relações Interpessoais , Autoimagem , Classe Social , Apoio Social , Humanos
7.
Sci Rep ; 7(1): 4060, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28642570

RESUMO

Magnetic skyrmions are hailed as a potential technology for data storage and other data processing devices. However, their stability against thermal fluctuations is an open question that must be answered before skyrmion-based devices can be designed. In this work, we study paths in the energy landscape via which the transition between the skyrmion and the uniform state can occur in interfacial Dzyaloshinskii-Moriya finite-sized systems. We find three mechanisms the system can take in the process of skyrmion nucleation or destruction and identify that the transition facilitated by the boundary has a significantly lower energy barrier than the other energy paths. This clearly demonstrates the lack of the skyrmion topological protection in finite-sized magnetic systems. Overall, the energy barriers of the system under investigation are too small for storage applications at room temperature, but research into device materials, geometry and design may be able to address this.

8.
Nanotechnology ; 27(45): 455502, 2016 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-27710921

RESUMO

Using finite element micromagnetic simulations, we study how resonant magnetisation dynamics in thin magnetic discs with perpendicular anisotropy are influenced by magnetostatic coupling to a magnetic nanoparticle. We identify resonant modes within the disc using direct magnetic eigenmode calculations and study how their frequencies and spatial profiles are changed by the nanoparticle's stray magnetic field. We demonstrate that particles can generate shifts in the resonant frequency of the disc's fundamental mode which exceed resonance linewidths in recently studied spin torque oscillator devices. Importantly, it is shown that the simulated shifts can be maintained over large field ranges (here up to 1 T). This is because the resonant dynamics (the basis of nanoparticle detection here) respond directly to the nanoparticle stray field, i.e. detection does not rely on nanoparticle-induced changes to the magnetic ground state of the disc. A consequence of this is that in the case of small disc-particle separations, sensitivities to the particle are highly mode- and particle-position-dependent, with frequency shifts being maximised when the intense stray field localised directly beneath the particle can act on a large proportion of the disc's spins that are undergoing high amplitude precession.

9.
Sci Rep ; 5: 17137, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26601904

RESUMO

Magnetic skyrmions have the potential to provide solutions for low-power, high-density data storage and processing. One of the major challenges in developing skyrmion-based devices is the skyrmions' magnetic stability in confined helimagnetic nanostructures. Through a systematic study of equilibrium states, using a full three-dimensional micromagnetic model including demagnetisation effects, we demonstrate that skyrmionic textures are the lowest energy states in helimagnetic thin film nanostructures at zero external magnetic field and in absence of magnetocrystalline anisotropy. We also report the regions of metastability for non-ground state equilibrium configurations. We show that bistable skyrmionic textures undergo hysteretic behaviour between two energetically equivalent skyrmionic states with different core orientation, even in absence of both magnetocrystalline and demagnetisation-based shape anisotropies, suggesting the existence of Dzyaloshinskii-Moriya-based shape anisotropy. Finally, we show that the skyrmionic texture core reversal dynamics is facilitated by the Bloch point occurrence and propagation.

10.
Nat Commun ; 5: 3660, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24755668

RESUMO

Pumice rafts are floating mobile accumulations of low-density pumice clasts generated by silicic volcanic eruptions. Pumice in rafts can drift for years, become waterlogged and sink, or become stranded on shorelines. Here we show that the pumice raft formed by the impressive, deep submarine eruption of the Havre caldera volcano (Southwest Pacific) in July 2012 can be mapped by satellite imagery augmented by sailing crew observations. Far from coastal interference, the eruption produced a single >400 km(2) raft in 1 day, thus initiating a gigantic, high-precision, natural experiment relevant to both modern and prehistoric oceanic surface dispersal dynamics. Observed raft dispersal can be accurately reproduced by simulating drift and dispersal patterns using currents from an eddy-resolving ocean model hindcast. For future eruptions that produce potentially hazardous pumice rafts, our technique allows real-time forecasts of dispersal routes, in addition to inference of ash/pumice deposit distribution in the deep ocean.

11.
Inflamm Bowel Dis ; 19(7): 1441-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23567780

RESUMO

BACKGROUND: Female patients receiving immunosuppressive therapy may be at increased risk for human papillomavirus (HPV) infection and cervical neoplasia. METHODS: We administered the 3-dose HPV vaccine Gardasil to 37 females aged 9 to 26 years with inflammatory bowel disease (IBD) prescribed immunosuppressive therapy (prospective cohort). Geometric mean titers (GMT) in milli-Merck (mMu/mL) units were determined before dose 1 and 1 month after dose 3 by competitive Luminex immunoassay (cLIA) and qualitatively compared with healthy females of similar age from Merck's database. Side effects and adverse events were evaluated. Concurrently, in 15 similar patients with inflammatory bowel disease previously vaccinated by their primary care provider, we assessed antibody titers by competitive Luminex immunoassay and total immunoglobulin G LIA after dose 3 of vaccine (range, 0.5-27 months). RESULTS: Mean age of prospective patients was 15 years with 51% on anti-tumor necrosis factor therapy and 49% on immunomodulators: 33 of 37 completed all 3 doses. Seropositivity after dose 3 was 100% for types 6, 11 and 16 and 96% for type 18. Geometric mean titers for HPV-6, HPV-11, HPV-16 and HPV-18 was 1080, 1682, 3975 and 858, respectively and did not qualitatively differ from healthy females. No serious adverse events were attributable to the vaccine. In the previously vaccinated cohort, seropositivity was 100% for types 6, 11, and 16, and 40% for type 18 by competitive Luminex immunoassay (93% for HPV-18 by immunoglobulin G LIA). Titers decreased with time since dose 3. CONCLUSIONS: In this small study of patients with inflammatory bowel disease prescribed immunosuppressive therapy, Gardasil was immunogenic and there were no clinically significant vaccine-associated adverse events.


Assuntos
Colite Ulcerativa/complicações , Doença de Crohn/complicações , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Colite Ulcerativa/imunologia , Colite Ulcerativa/virologia , Doença de Crohn/imunologia , Doença de Crohn/virologia , Feminino , Seguimentos , Hospitalização , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Humanos , Masculino , Dose Máxima Tolerável , Papillomaviridae/classificação , Infecções por Papillomavirus/etiologia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
12.
J Pediatr Gastroenterol Nutr ; 55(1): 32-43, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22197944

RESUMO

OBJECTIVES: Genotypic variation in signal transducer and activator of transcription 3 (STAT3) increases risk for inflammatory bowel disease (IBD), and STAT3-dependent inflammatory networks are induced in the colon in these patients. We hypothesized that STAT3 "A" risk allele carriage would be associated with increased cellular STAT3 activation and colon leukocyte recruitment. METHODS: Colonic expression of genes regulating STAT3 signaling and leukocyte recruitment and function was measured in pediatric patients with Crohn disease (CD) stratified by STAT3 genotype. The frequency of colonic pSTAT3* and CXCR2* neutrophils was determined using immunohistochemistry. STAT3 tyrosine phosphorylation (pSTAT3) was measured in circulating leukocytes by flow cytometry, and mechanisms regulating STAT3 activation were tested in IBD Epstein-Barr virus (EBV)-transformed lymphocytes (EBL). RESULTS: Colonic expression of interleukin 6 (IL-6), the STAT3 target gene SOCS3, the neutrophil chemoattractants IL-8, CXCL1, and CXCL3, and the neutrophil products S100A8, S100A9, and S100A12 were increased in patients carrying the STAT3 "A" risk allele. The frequency of neutrophils expressing the cognate receptor for IL-8, CXCR2, was increased in colonic biopsies from patients carrying the risk allele, and the frequency of pSTAT3* or CXCR2* neutrophils correlated with histologic severity. The frequency of CD4 lymphocytes and granulocytes expressing pSTAT3 was increased in patients carrying the STAT3 "A" risk allele. EBLs from patients carrying the STAT3 "A" risk allele exhibited increased basal and IL-6-stimulated STAT3 tyrosine phosphorylation, increased transcription of STAT3 and SOCS3 after IL-6 stimulation, and increased membrane localization of the IL-6 receptor, GP130, and Janus-associated kinase 2. CONCLUSIONS: The STAT3 "A" risk allele is associated with increased cellular STAT3 activation and upregulation of pathways that promote recruitment of CXCR2* neutrophils to the gut.


Assuntos
Colo/metabolismo , Doença de Crohn/genética , Doença de Crohn/metabolismo , Neutrófilos/metabolismo , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética , Adolescente , Alelos , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Células Cultivadas , Quimiocina CXCL1/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Criança , Colo/imunologia , Colo/patologia , Doença de Crohn/patologia , Feminino , Expressão Gênica , Variação Genética , Genótipo , Humanos , Interleucina-1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Janus Quinase 2/metabolismo , Contagem de Linfócitos , Masculino , Fosforilação , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-8B/metabolismo , Proteínas S100/metabolismo , Proteína S100A12 , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Tirosina/metabolismo , Regulação para Cima
13.
J Pediatr Gastroenterol Nutr ; 51(2): 130-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20453679

RESUMO

OBJECTIVES: Growth hormone (GH) may reduce symptoms and improve growth in Crohn disease (CD). The effect on mucosal inflammation is not known. We hypothesized that GH would improve both clinical and mucosal disease activity and stimulate linear growth in pediatric CD. PATIENTS AND METHODS: Twenty patients ages 7 to 18 receiving corticosteroids (CTX) for active CD were randomized to begin GH, 0.075 mg x kg(-1) x day(-1) (group A), or continue CTX alone (group B). Clinical and endoscopic disease activities were assessed after 12 weeks. Group B began GH at 12 weeks, and clinical disease activity was assessed at 24 weeks. Subjects who experienced a clinical response after 12 weeks of GH therapy continued treatment for an additional 52 weeks, and linear growth was assessed. RESULTS: Sixty-five percent of patients receiving GH achieved clinical remission, compared with 20% treated with CTX alone (P = 0.03). Although endoscopic disease activity trended toward an improvement at week 12 in group A, this did not differ between the groups. Sixty-one percent of week 12 GH responders maintained their clinical response through week 64. Mean (95th confidence interval) height z score on GH increased from -1.1 (-1.6, -0.6) to -0.4 (-1, 0.2), P = 0.004 during this 52-week extension phase. GH was well tolerated with no unexpected safety signals. CONCLUSIONS: The addition of GH to CTX therapy did not induce a reduction in mucosal inflammation, relative to CTX alone. However, GH was safe and effective as an adjunct to CTX for treatment of clinical disease activity and growth failure in pediatric CD.


Assuntos
Colo/efeitos dos fármacos , Doença de Crohn/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Mucosa Intestinal/efeitos dos fármacos , Adolescente , Corticosteroides/uso terapêutico , Criança , Colo/patologia , Colonoscopia , Doença de Crohn/patologia , Quimioterapia Combinada , Feminino , Hormônio do Crescimento Humano/farmacologia , Humanos , Mucosa Intestinal/patologia , Masculino , Indução de Remissão , Método Simples-Cego
14.
Pediatr Transplant ; 14(1): 115-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19254244

RESUMO

To evaluate hyponatremia as an independent predictor of mortality in pediatric patients with end-stage liver disease listed for transplantation. We performed a single-center retrospective study of children listed for liver transplantation. We defined hyponatremia as a serum sodium concentration <130 mEq/L that persisted for at least seven days. The primary outcome was death on the waiting list. Ninety-four patients were eligible for the study. The prevalence of hyponatremia was 26%. Kaplan-Meier survival analysis demonstrated that patients with hyponatremia had decreased pretransplant survival compared with patients who maintained a serum sodium >130 mEq/L (p < 0.001). Univariable association analyses demonstrated death on the waiting list was also associated with higher median PELD scores at listing (p = 0.01), non-white race (p = 0.02), and age <1 yr (p = 0.001). Logistic regression analysis identified hyponatremia and non-white race as independently associated with pretransplant mortality [OR = 8.0 (95% CI: 1.4-45.7), p = 0.02 and OR = 6.3 (95% CI: 1.25-33.3), p = 0.03]. When hyponatremia was added to the PELD score, it was significantly better in predicting mortality than the PELD score alone (c-statistic = 0.79, p = 0.03). Hyponatremia identifies a subset of pediatric patients with increased risk of pretransplant mortality and improves the predictive ability of the current PELD score.


Assuntos
Hiponatremia/mortalidade , Falência Hepática/mortalidade , Transplante de Fígado , Listas de Espera , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Falência Hepática/sangue , Falência Hepática/cirurgia , Masculino , Período Pré-Operatório , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Estados Unidos
15.
J Immunol ; 181(10): 7390-9, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18981162

RESUMO

Clinical studies have demonstrated a link between the eosinophil-selective chemokines, eotaxins (eotaxin-1/CCL11 and eotaxin-2/CCL24), eosinophils, and the inflammatory bowel diseases, Crohn's disease and ulcerative colitis (UC). However, the cellular source and individual contribution of the eotaxins to colonic eosinophilic accumulation in inflammatory bowel diseases remain unclear. In this study we demonstrate, by gene array and quantitative PCR, elevated levels of eotaxin-1 mRNA in the rectosigmoid colon of pediatric UC patients. We show that elevated levels of eotaxin-1 mRNA positively correlated with rectosigmoid eosinophil numbers. Further, colonic eosinophils appeared to be degranulating, and the levels positively correlated with disease severity. Using the dextran sodium sulfate (DSS)-induced intestinal epithelial injury model, we show that DSS treatment of mice strongly induced colonic eotaxin-1 and eotaxin-2 expression and eosinophil levels. Analysis of eosinophil-deficient mice defined an effector role for eosinophils in disease pathology. DSS treatment of eotaxin-2(-/-) and eotaxin-1/2(-/-) mice demonstrated that eosinophil recruitment was dependent on eotaxin-1. In situ and immunofluorescence analysis-identified eotaxin-1 expression was restricted to intestinal F4/80(+)CD11b(+) macrophages in DSS-induced epithelial injury and to CD68(+) intestinal macrophages and the basolateral compartment of intestinal epithelial cells in pediatric UC. These data demonstrate that intestinal macrophage and epithelial cell-derived eotaxin-1 plays a critical role in the regulation of eosinophil recruitment in colonic eosinophilic disease such as pediatric UC and provides a basis for targeting the eosinophil/eotaxin-1 axis in UC.


Assuntos
Quimiocina CCL11/biossíntese , Quimiotaxia de Leucócito/imunologia , Colite Ulcerativa/imunologia , Eosinófilos/metabolismo , Células Epiteliais/metabolismo , Macrófagos/metabolismo , Adolescente , Animais , Criança , Pré-Escolar , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colo/citologia , Colo/imunologia , Eosinófilos/imunologia , Células Epiteliais/imunologia , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Macrófagos/imunologia , Masculino , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Inflamm Bowel Dis ; 14(4): 446-57, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18069684

RESUMO

BACKGROUND: While activation of the IL-6-dependent transcription factor signal transducer and activator of transcription 3 (STAT3) has been implicated in the pathogenesis of inflammatory bowel disease (IBD), a direct effect on mucosal gene expression and inflammation has not been shown. We hypothesized that a proinflammatory IL-6:STAT3-dependent biological network would be up regulated in pediatric-onset IBD patients, and would be associated with the severity of mucosal inflammation. METHODS: Patients with pediatric-onset IBD were enrolled at diagnosis and during therapy. Serum cytokine analysis was performed using Bioplex. STAT3 phosphorylation (pSTAT3) in peripheral blood leukocytes (PBLs) was assessed by flow cytometry. Immunohistochemistry of colonic mucosa was used to localize pSTAT3 and STAT3 target genes. Microarray analysis was used to determine RNA expression profiles from colon biopsies. RESULTS: Circulating IL-6 was upregulated in active IBD patients at diagnosis and during therapy. STAT3 activation was increased in PB granulocytes, IL-6-stimulated CD3(+)/CD4(+) lymphocytes, and affected colon biopsies of IBD patients. The frequency of pSTAT3+ PB granulocytes and colon epithelial and lamina propria cells was highly correlated with the degree of mucosal inflammation. Microarray and Ingenuity Systems bioinformatics analysis identified IL-6:STAT3-dependent biological networks upregulated in IBD patients which control leukocyte recruitment, HLA expression, angiogenesis, and tissue remodeling. CONCLUSIONS: A proinflammatory IL6:STAT3 biologic network is upregulated in active pediatric IBD patients at diagnosis and during therapy. Specific targeting of this network may be effective in reducing mucosal inflammation.


Assuntos
Doenças Inflamatórias Intestinais/metabolismo , Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Adolescente , Quimiocina CXCL10/metabolismo , Quimiocina CXCL11/metabolismo , Criança , Colo/metabolismo , Colo/patologia , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Inflamação , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Interleucina-6/genética , Mucosa Intestinal/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT3/genética , Ativação Transcricional , Regulação para Cima
17.
J Neurosci ; 22(5): 1583-91, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11880488

RESUMO

Generation of distinct cell types and numbers in developing cerebral cortex is subject to regulation by extracellular factors that positively or negatively control precursor proliferation. Although signals stimulating proliferation are well described, factors halting cell cycle progression are less well defined. At the molecular level, production and association of cyclins, cyclin-dependent kinases (CDKs), and CDK inhibitors (CKIs) regulate cycle progression. We now report that the endogenous peptide, pituitary adenylate cyclase activating polypeptide (PACAP), negatively regulates the cell cycle by inhibiting p57Kip2-dependent CDK2 activity in embryonic cortex. Protein levels of CDK2 and members of the CIP/KIP family of CKIs (p27Kip1, p57Kip2) were detected in developing rat cortex from embryonic day 13.5 through postnatal day 2. With advancing development, CDK2 protein levels decreased, whereas CKI expression increased, suggesting that stimulatory and inhibitory cycle proteins control cell cycle exit. Using a well defined, nonsynchronized, 8 hr precursor culture, PACAP decreased the fraction of cells crossing the G1/S boundary, inhibiting DNA synthesis by 35%. CDK2 kinase activity was inhibited 75% by PACAP, whereas kinase protein and its regulatory cyclin E subunit were unaffected. Moreover, decreased kinase activity was accompanied by a twofold increase in levels of p57Kip2 protein, but not p21Cip1 or p27Kip1, suggesting that p57Kip2 mediates PACAP anti-mitogenic effects. Indeed, immunoprecipitation of CDK2 complex revealed increased p57Kip2 association with the kinase and concomitant reduction in free inhibitor after PACAP exposure, suggesting that p57Kip2 interactions directly regulate CDK2 activity. These observations establish a mechanism whereby anti-mitogenic signals actively induce cell cycle withdrawal in developing cortex.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/metabolismo , Neuropeptídeos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/metabolismo , Linhagem da Célula/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Inibidor de Quinase Dependente de Ciclina p57 , DNA/biossíntese , Desenvolvimento Embrionário e Fetal/fisiologia , Células HeLa , Humanos , Immunoblotting , Substâncias Macromoleculares , Mitose/efeitos dos fármacos , Mitose/fisiologia , Neuropeptídeos/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Proteínas Supressoras de Tumor/metabolismo
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