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1.
J Med Libr Assoc ; 112(3): 205-213, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39308909

RESUMO

On the occasion of the Medical Library Association's 125th Anniversary, four librarian leaders with a combined 105 years of engagement in MLA collaborated to reflect on the changes in our profession and our association. We draw on an examination of the last 25 years of the MLA Janet Doe Lectures, our own personal histories, and scholarship we produced for MLA publications and presentations. We offer this compilation as an invitation for readers to reflect on their experiences of changes within the profession, inspiration to engage in the issues around our place in society, and a source for additional exploration into researching and learning from our collective history.


Assuntos
Liderança , Bibliotecas Médicas , Associações de Bibliotecas , Bibliotecas Médicas/história , Associações de Bibliotecas/história , Humanos , História do Século XXI , História do Século XX , Bibliotecários/história , Estados Unidos
2.
Inorg Chem ; 62(45): 18357-18374, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37314463

RESUMO

A series of manganese(II) and oxomanganese(IV) complexes supported by neutral, pentadentate ligands with varied equatorial ligand-field strength (N3pyQ, N2py2I, and N4pyMe2) were synthesized and then characterized using structural and spectroscopic methods. On the basis of electronic absorption spectroscopy, the [MnIV(O)(N4pyMe2)]2+ complex has the weakest equatorial ligand field among a set of similar MnIV-oxo species. In contrast, [MnIV(O)(N2py2I)]2+ shows the strongest equatorial ligand-field strength for this same series. We examined the influence of these changes in electronic structure on the reactivity of the oxomanganese(IV) complexes using hydrocarbons and thioanisole as substrates. The [MnIV(O)(N3pyQ)]2+ complex, which contains one quinoline and three pyridine donors in the equatorial plane, ranks among the fastest MnIV-oxo complexes in C-H bond and thioanisole oxidation. While a weak equatorial ligand field has been associated with high reactivity, the [MnIV(O)(N4pyMe2)]2+ complex is only a modest oxidant. Buried volume plots suggest that steric factors dampen the reactivity of this complex. Trends in reactivity were examined using density functional theory (DFT)-computed bond dissociation free energies (BDFEs) of the MnIIIO-H and MnIV ═ O bonds. We observe an excellent correlation between MnIV═O BDFEs and rates of thioanisole oxidation, but more scatter is observed between hydrocarbon oxidation rates and the MnIIIO-H BDFEs.

3.
Ecol Appl ; 31(8): e02446, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34448316

RESUMO

Ecological forecasts will be best suited to inform intervention strategies if they are accessible to a diversity of decision-makers. Researchers are developing intuitive forecasting interfaces to guide stakeholders through the development of intervention strategies and visualization of results. Yet, few studies to date have evaluated how user interface design facilitates the coordinated, cross-boundary management required for controlling biological invasions. We used a participatory approach to develop complementary tangible and online interfaces for collaboratively forecasting biological invasions and devising control strategies. A diverse group of stakeholders evaluated both systems in the real-world context of controlling sudden oak death, an emerging forest disease killing millions of trees in California and Oregon. Our findings suggest that while both interfaces encouraged adaptive experimentation, tangible interfaces are particularly well suited to support collaborative decision-making. Reflecting on the strengths of both systems, we suggest workbench-style interfaces that support simultaneous interactions and dynamic geospatial visualizations.


Assuntos
Monitoramento Ambiental/métodos , Previsões , California , Internet , Espécies Introduzidas , Oregon , Doenças das Plantas , Quercus
4.
Front Ecol Environ ; 19(7): 411-418, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34588928

RESUMO

Ecological forecasting has vast potential to support environmental decision making with repeated, testable predictions across management-relevant timescales and locations. Yet resource managers rarely use co-designed forecasting systems or embed them in decision making. Although prediction of planned management outcomes is particularly important for biological invasions to optimize when and where resources should be allocated, spatial-temporal models of spread typically have not been openly shared, iteratively updated, or interactive to facilitate exploration of management actions. We describe a species-agnostic, open-source framework - called the Pest or Pathogen Spread (PoPS) Forecasting Platform - for co-designing near-term iterative forecasts of biological invasions. Two case studies are presented to demonstrate that iterative calibration yields higher forecast skill than using only the earliest-available data to predict future spread. The PoPS framework is a primary example of an ecological forecasting system that has been both scientifically improved and optimized for real-world decision making through sustained participation and use by management stakeholders.

5.
Pediatr Exerc Sci ; 33(4): 196-202, 2021 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-34303306

RESUMO

BACKGROUND: Elevated left ventricular outflow tract (LVOT) gradients during exercise can occur in patients with hypertrophic cardiomyopathy (HCM) as well as in athletes and normal controls. The authors' staged exercise protocol calls for imaging at rest and during each stage of exercise to evaluate the mechanism of LVOT obstruction at each stage. They investigated whether this staged approach helps differentiate HCM from athletes and normal controls. METHODS: They reviewed pediatric exercise stress echocardiograms completed between January 2009 and October 2017 at their center and identified those with gene-positive HCM, athlete's heart, and normal controls. Children with inducible obstruction (those with no LVOT gradient at rest who developed a LVOT peak gradient > 25 mm Hg during exercise) were included. LVOT peak gradient, velocity time integral, acceleration time, and deceleration time were measured at rest, submaximal stages, and peak exercise. RESULTS: Compared with athletes, HCM patients had significantly higher LVOT peak gradients at rest (P = .019), stage 1 of exercise (P = .002), and peak exercise (P = .051), as well as a significantly higher change in LVOT peak gradient from rest to stage 1 (P = .016) and from rest to peak (P = .038). The acceleration time/deceleration time ratio of the LVOT Doppler was significantly lower in HCM patients compared with normal controls at peak exercise. CONCLUSIONS: The HCM patients who develop elevated LVOT gradients at peak exercise typically manifest early obstruction in the submaximal stages of exercise, which helps to differentiate them from athletes and normal controls.


Assuntos
Cardiomiopatia Hipertrófica , Obstrução do Fluxo Ventricular Externo , Atletas , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Criança , Ecocardiografia sob Estresse , Teste de Esforço , Humanos , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem
6.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884909

RESUMO

The limited ability of mammalian adult cardiomyocytes to proliferate following an injury to the heart, such as myocardial infarction, is a major factor that results in adverse fibrotic and myocardial remodeling that ultimately leads to heart failure. The continued high degree of heart failure-associated morbidity and lethality requires the special attention of researchers worldwide to develop efficient therapeutics for cardiac repair. Recently, various strategies and approaches have been developed and tested to extrinsically induce regeneration and restoration of the myocardium after cardiac injury have yielded encouraging results. Nevertheless, these interventions still lack adequate success to be used for clinical interventions. This review highlights and discusses both cell-based and cell-free therapeutic approaches as well as current advancements, major limitations, and future perspectives towards developing an efficient therapeutic method for cardiac repair.


Assuntos
Infarto do Miocárdio/patologia , Comunicação Parácrina , Animais , Terapia Baseada em Transplante de Células e Tecidos , Exossomos/metabolismo , Exossomos/transplante , Humanos , Infarto do Miocárdio/terapia , Comunicação Parácrina/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
7.
Arterioscler Thromb Vasc Biol ; 38(6): 1271-1282, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29599135

RESUMO

OBJECTIVE: PAR2 (protease-activated receptor 2)-dependent signaling results in augmented inflammation and has been implicated in the pathogenesis of several autoimmune conditions. The objective of this study was to determine the effect of PAR2 deficiency on the development of atherosclerosis. APPROACH AND RESULTS: PAR2 mRNA and protein expression is increased in human carotid artery and mouse aortic arch atheroma versus control carotid and aortic arch arteries, respectively. To determine the effect of PAR2 deficiency on atherosclerosis, male and female low-density lipoprotein receptor-deficient (Ldlr-/-) mice (8-12 weeks old) that were Par2+/+ or Par2-/- were fed a fat- and cholesterol-enriched diet for 12 or 24 weeks. PAR2 deficiency attenuated atherosclerosis in the aortic sinus and aortic root after 12 and 24 weeks. PAR2 deficiency did not alter total plasma cholesterol concentrations or lipoprotein distributions. Bone marrow transplantation showed that PAR2 on nonhematopoietic cells contributed to atherosclerosis. PAR2 deficiency significantly attenuated levels of the chemokines Ccl2 and Cxcl1 in the circulation and macrophage content in atherosclerotic lesions. Mechanistic studies using isolated primary vascular smooth muscle cells showed that PAR2 deficiency is associated with reduced Ccl2 and Cxcl1 mRNA expression and protein release into the supernatant resulting in less monocyte migration. CONCLUSIONS: Our results indicate that PAR2 deficiency is associated with attenuation of atherosclerosis and may reduce lesion progression by blunting Ccl2- and Cxcl1-induced monocyte infiltration.


Assuntos
Aorta Torácica/metabolismo , Doenças da Aorta/prevenção & controle , Aterosclerose/prevenção & controle , Receptor PAR-2/deficiência , Animais , Aorta Torácica/patologia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Movimento Celular , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Humanos , Lipídeos/sangue , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Fenótipo , Placa Aterosclerótica , Receptor PAR-1/deficiência , Receptor PAR-1/genética , Receptor PAR-2/genética , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Receptores de LDL/deficiência , Receptores de LDL/genética
8.
Pediatr Cardiol ; 40(8): 1670-1678, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542803

RESUMO

Although elevated right ventricular pressure and left ventricular diastolic dysfunction measured by echocardiogram are independent predictors of death in adults with sickle cell disease (SCD), the utility of routine echocardiographic screening in the pediatric population is controversial. We performed a 3-year retrospective review of children ≥ 10 years of age with SCD who underwent an outpatient transthoracic echocardiogram as part of a screening program. Of 172 patients referred for screening, 105 (61%) had a measurable tricuspid regurgitation jet velocity (TRV): median 2.4 m/s (IQR 2.3-2.5). Elevated right ventricular (RV) pressure (TRV ≥ 2.5 m/s, 25 mmHg), documented in 30% (32/105), was significantly associated with chronic transfusion therapy and elevated lactate dehydrogenase. Left ventricle (LV) dilation, documented in 25% (44/172), was significantly associated with lower hemoglobin, and higher reticulocyte count, lactate dehydrogenase level, and bilirubin level. There was no association between elevated right ventricular pressure or left ventricle dilation and indices of biventricular systolic or diastolic function. The one death in the cohort during the study period had normal echocardiographic findings. In conclusion, mild RV pressure elevation and LV dilation in children with SCD is associated with abnormal laboratory markers of disease severity, but not with ventricular dysfunction over the 3-year study period.


Assuntos
Anemia Falciforme/fisiopatologia , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia , Adolescente , Anemia Falciforme/complicações , Criança , Progressão da Doença , Ecocardiografia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Medição de Risco
9.
Am J Physiol Heart Circ Physiol ; 315(6): H1748-H1758, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30216115

RESUMO

The present study assessed whether tefillin use (tight, nonocclusive, wrapping of the arm) elicits a remote ischemic preconditioning (RIPC)-like effect in subjects with both acute and chronic use. RIPC, created by short bursts of ischemia-reperfusion, has not been successfully taken to the bedside. Several large population studies have found that Orthodox Jewish men (who wear tefillin almost daily) have decreased cardiovascular mortality compared with non-Orthodox counterparts. We hypothesized that tefillin use is a relevant component in triggering a preconditioning effect. Jewish men ( n = 20) were enrolled; 9 men were daily tefillin users (conditioned) and 11 men were nonusers of tefillin as controls (naïve). Subjects were evaluated for adherence to traditional Jewish practice, had vital signs measured, blood drawn for analysis of circulating cytokines and monocyte function, and underwent brachial flow-mediated dilation to evaluate vascular reactivity at baseline (basal) and after 30 min of using tefillin (acute treatment). Under basal conditions, both groups had similar peak systolic velocity (SV), diameter, and flow volume, although the conditioned group had higher SV at 120 s postdeflation ( P = 0.05). Acute tefillin use augmented artery diameter and flow volume in both groups, with conditioned subjects experiencing higher SV than control subjects at 90 and 120 s postdeflation ( P = 0.03 and P = 0.02, respectively). Conditioned subjects had decreased inflammation, monocyte migration and adhesion, and endothelial activation compared with control subjects at baseline. Acute use of tefillin did not significantly alter monocyte function in either group. In this pilot study, acute tefillin use improves vascular function, whereas chronic tefillin use is associated with an anti-inflammatory RIPC-like phenotype. NEW & NOTEWORTHY We hypothesized that tefillin use among Orthodox Jewish men (who practice a nonocclusive leather banding of their nondominant arm) will induce a remote ischemic preconditioning phenotype. Chronic use of tefillin in Orthodox Jewish men was associated with increased systolic velocity and attenuated inflammation and monocyte chemotaxis and adhesion versus Jewish men who do not wear tefillin. Acute use of tefillin in both populations augmented brachial artery diameter and blood flow but not inflammatory profiles compared with baseline.


Assuntos
Artéria Braquial/fisiologia , Bandagens Compressivas/efeitos adversos , Precondicionamento Isquêmico/métodos , Judaísmo , Adolescente , Adulto , Braço/irrigação sanguínea , Artéria Braquial/metabolismo , Estudos de Casos e Controles , Citocinas/metabolismo , Endotélio Vascular/metabolismo , Hemodinâmica , Humanos , Precondicionamento Isquêmico/efeitos adversos , Masculino
10.
Inorg Chem ; 57(13): 7825-7837, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29927591

RESUMO

The solution properties of MnIII-hydroxo and MnIII-methoxy complexes featuring N5 amide-containing ligands were investigated using 1H NMR spectroscopy. The 1H NMR spectrum for one of these complexes, the previously reported [MnIII(OH)(dpaq)](OTf) (dpaq = 2-[bis(pyridin-2-ylmethyl)]amino- N-quinolin-8-yl-acetamidate) shows hyperfine-shifted signals, as expected for this S = 2 MnIII-hydroxo adduct. However, the 1H NMR spectrum of [MnIII(OH)(dpaq)](OTf) also shows a large number of proton resonances in the diamagnetic region, suggesting the presence of multiple species in CD3CN solution. The majority of the signals in the diamagnetic region disappear when a small amount of water is added to a CH3CN solution of [MnIII(OH)(dpaq)](OTf). Electronic absorption and Mn K-edge X-ray absorption experiments support the formulation of this diamagnetic species as the µ-oxodimanganese(III,III) complex [MnIII2(µ-O)(dpaq)2)]2+. On the basis of these observations, we propose that the dissolution of [MnIII(OH)(dpaq)](OTf) in CD3CN results in the formation of mononuclear MnIII-hydroxo and dinuclear µ-oxodimanganese(III,III) species that are in equilibrium. The addition of a small amount of water is sufficient to shift this equilibrium in favor of the MnIII-hydroxo adduct. Surprisingly, electronic absorption experiments show that the conversion of [MnIII2(µ-O)(dpaq)2)]2+ to [MnIII(OH)(dpaq)]+ by added water is relatively slow. Because this dimer to monomer conversion is slower than TEMPOH oxidation by [MnIII(OH)(dpaq)]+, the previously observed TEMPOH oxidation rates for [MnIII(OH)(dpaq)]+ reflected both processes. Here, we report the bona fide TEMPOH oxidation rate for [MnIII(OH)(dpaq)]+, which is significantly faster than previously reported. 1H NMR spectra are also reported for the related [MnIII(OMe)(dpaq)]+ and [MnIII(OH)(dpaq2Me)]+ complexes. These spectra only show hyperfine-shifted signals, suggesting the presence of only mononuclear MnIII-methoxy and MnIII-hydroxo species in solution. Measurements of T1 relaxation times and proton peak integrations for [MnIII(OMe)(dpaq)]+ provide preliminary assignments for 1H NMR resonances.

11.
J Immunol ; 196(1): 196-206, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26621863

RESUMO

Memory B cell responses are vital for protection against infections but must also be regulated to prevent autoimmunity. Cognate T cell help, somatic hypermutation, and affinity maturation within germinal centers (GCs) are required for high-affinity memory B cell formation; however, the signals that commit GC B cells to the memory pool remain unclear. In this study, we identify a role for IgG-immune complexes (ICs), FcγRs, and BAFF during the formation of memory B cells in mice. We found that early secretion of IgG in response to immunization with a T-dependent Ag leads to IC-FcγR interactions that induce dendritic cells to secrete BAFF, which acts at or upstream of Bcl-6 in activated B cells. Loss of CD16, hematopoietic cell-derived BAFF, or blocking IC:FcγR regions in vivo diminished the expression of Bcl-6, the frequency of GC and memory B cells, and secondary Ab responses. BAFF also contributed to the maintenance and/or expansion of the follicular helper T cell population, although it was dispensable for their formation. Thus, early Ab responses contribute to the optimal formation of B cell memory through IgG-ICs and BAFF. Our work defines a new role for FcγRs in GC and memory B cell responses.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Fator Ativador de Células B/biossíntese , Imunoglobulina G/imunologia , Memória Imunológica/imunologia , Receptores de IgG/imunologia , Transferência Adotiva , Animais , Fator Ativador de Células B/genética , Linfócitos B/citologia , Linfócitos B/imunologia , Diferenciação Celular/imunologia , Células Cultivadas , Células Dendríticas/imunologia , Centro Germinativo/citologia , Centro Germinativo/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-6/biossíntese , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Receptores de IgG/genética , Linfócitos T Auxiliares-Indutores/imunologia
12.
J Med Libr Assoc ; 106(4): 411-415, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30271281

RESUMO

When I think of Beverly Murphy, AHIP, FMLA, three words come to mind: Bold, Brave, Brilliant. In every action that Beverly has undertaken as a health sciences librarian, she has demonstrated an innate ability to just "Be." Being bold, brave, and brilliant is just what she will need to be as the Medical Library Association's first African-American president since the association's founding in 1898.


Assuntos
Bibliotecários/história , Bibliotecas Médicas/história , Associações de Bibliotecas/história , Serviços de Biblioteca/história , História do Século XXI , Humanos , Liderança , Inovação Organizacional , Papel Profissional , Estados Unidos
13.
Aging Clin Exp Res ; 29(5): 863-873, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27804106

RESUMO

BACKGROUND: The aging heart is characterized by cellular and molecular changes leading to a decline in physiologic function and cardiac remodeling, specifically the development of myocyte hypertrophy and fibrosis. Transient receptor potential vanilloid 2 (TRPV2), a stretch-mediated channel and regulator of calcium homeostasis, plays a key role in the function and structure of the heart. TRPV2 also plays an important role in the adaptive and maladaptive compensatory mechanisms of the heart in response to pathologic and exercise-induced stress. Our current study seeks to elucidate the potential role of TRPV2 channels in the regulation of cardiac function in aging. METHODS: Wild-type (WT) and TRPV2 functional knockout (FKO) mice were aged out to various time points, and their cardiac function was measured using advanced echocardiography. Furthermore, we histologically analyzed the heart morphology to determine myocyte hypertrophy, the development of fibrosis and the relative expression of TRPV2. RESULTS: Our results demonstrate that even though TRPV2-FKO mice have impaired function at baseline, their cardiac function as measured via standard and advanced echocardiographic parameters (ejection fraction, cardiac output and circumferential strain) decreased less with aging in comparison with the WT group. Furthermore, there was less fibrosis and hypertrophy in the TRPV2-FKO group with aging in comparison with the WT. The expression of TRPV2 in the WT group did not significantly change with aging. CONCLUSIONS: TRPV2 functional deletion is compatible with aging and associated with a decreased development of myocyte hypertrophy and fibrosis. It may be an important target for prevention of age-induced cardiac remodeling.


Assuntos
Ecocardiografia/métodos , Coração/fisiopatologia , Canais de Cátion TRPV/genética , Animais , Feminino , Fibrose , Masculino , Camundongos , Camundongos Knockout
14.
Circulation ; 132(15): 1387-94, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26246174

RESUMO

BACKGROUND: Intramural ventricular septal defects (VSDs) are interventricular communications through right ventricular free wall trabeculations that can occur after repair of conotruncal anomalies. We assessed the prevalence of residual intramural VSDs and their effect on postoperative course. METHODS AND RESULTS: Children who underwent biventricular repair of a conotruncal anomaly from January 1, 2006, to June 30, 2013, and had a postoperative transthoracic echocardiogram were included. Images were reviewed for residual intramural or nonintramural VSDs. The primary outcome was a composite of mortality, extracorporeal membrane oxygenation use, and need for subsequent catheter or surgical VSD closure. The secondary outcome was postoperative hospital length of stay. A residual VSD was present in 256 of the 442 subjects (58%), of which 231 (90%) were <2 mm in size. Forty-nine patients (11%) had intramural VSDs, and 207 (47%) had nonintramural VSDs. Patients with intramural VSDs were more likely to reach the primary composite outcome compared with those with nonintramural VSDs or no residual VSD (14 of 49 [29%] versus 15 of 207 [7%] versus 6 of 186 [3%]; P<0.0001). In addition, those with intramural VSDs had longer postoperative hospital length of stay compared with those with nonintramural VSDs or no residual VSD (20 days [interquartile range, 11-42 days] versus 7 days [interquartile range, 5-14 days] versus 6 days [interquartile range, 4-11 days]; P=0.0001). These associations remained significant after adjustment for known risk factors for poor outcomes, including residual VSD size and operative complexity. CONCLUSIONS: Among residual VSDs after repair of conotruncal anomalies, intramural VSDs are uniquely associated with postoperative morbidity, mortality, and longer postoperative hospital length of stay. It is important to recognize intramural VSDs in the postoperative period.


Assuntos
Cardiopatias Congênitas/cirurgia , Comunicação Interventricular/etiologia , Complicações Pós-Operatórias/etiologia , Tronco Arterial/anormalidades , Cateterismo Cardíaco/estatística & dados numéricos , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Feminino , Comunicação Interventricular/diagnóstico por imagem , Comunicação Interventricular/epidemiologia , Comunicação Interventricular/cirurgia , Septos Cardíacos/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/cirurgia , Tempo de Internação/estatística & dados numéricos , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Prevalência , Reoperação/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento , Tronco Arterial/cirurgia , Ultrassonografia
15.
J Exp Biol ; 219(Pt 23): 3759-3772, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27903629

RESUMO

The smallest flying insects commonly possess wings with long bristles. Little quantitative information is available on the morphology of these bristles, and their functional importance remains a mystery. In this study, we (1) collected morphological data on the bristles of 23 species of Mymaridae by analyzing high-resolution photographs and (2) used the immersed boundary method to determine via numerical simulation whether bristled wings reduced the force required to fling the wings apart while still maintaining lift. The effects of Reynolds number, angle of attack, bristle spacing and wing-wing interactions were investigated. In the morphological study, we found that as the body length of Mymaridae decreases, the diameter and gap between bristles decreases and the percentage of the wing area covered by bristles increases. In the numerical study, we found that a bristled wing experiences less force than a solid wing. The decrease in force with increasing gap to diameter ratio is greater at higher angles of attack than at lower angles of attack, suggesting that bristled wings may act more like solid wings at lower angles of attack than they do at higher angles of attack. In wing-wing interactions, bristled wings significantly decrease the drag required to fling two wings apart compared with solid wings, especially at lower Reynolds numbers. These results support the idea that bristles may offer an aerodynamic benefit during clap and fling in tiny insects.


Assuntos
Fenômenos Biomecânicos/fisiologia , Voo Animal/fisiologia , Himenópteros/anatomia & histologia , Himenópteros/fisiologia , Asas de Animais/anatomia & histologia , Animais , Hidrodinâmica , Modelos Biológicos
16.
J Exp Biol ; 217(Pt 21): 3898-909, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25189374

RESUMO

The aerodynamics of flapping flight for the smallest insects such as thrips is often characterized by a 'clap and fling' of the wings at the end of the upstroke and the beginning of the downstroke. These insects fly at Reynolds numbers (Re) of the order of 10 or less where viscous effects are significant. Although this wing motion is known to augment the lift generated during flight, the drag required to fling the wings apart at this scale is an order of magnitude larger than the corresponding force acting on a single wing. As the opposing forces acting normal to each wing nearly cancel during the fling, these large forces do not have a clear aerodynamic benefit. If flight efficiency is defined as the ratio of lift to drag, the clap and fling motion dramatically reduces efficiency relative to the case of wings that do not aerodynamically interact. In this paper, the effect of a bristled wing characteristic of many of these insects was investigated using computational fluid dynamics. We performed 2D numerical simulations using a porous version of the immersed boundary method. Given the computational complexity involved in modeling flow through exact descriptions of bristled wings, the wing was modeled as a homogeneous porous layer as a first approximation. High-speed video recordings of free-flying thrips in take-off flight were captured in the laboratory, and an analysis of the wing kinematics was performed. This information was used for the estimation of input parameters for the simulations. Compared with a solid wing (without bristles), the results of the study show that the porous nature of the wings contributes largely to drag reduction across the Re range explored. The aerodynamic efficiency, calculated as the ratio of lift to drag coefficients, was larger for some porosities when compared with solid wings.


Assuntos
Voo Animal/fisiologia , Modelos Biológicos , Tisanópteros/fisiologia , Asas de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Hidrodinâmica , Gravação em Vídeo , Asas de Animais/anatomia & histologia
17.
J Immunol ; 189(2): 711-20, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22675201

RESUMO

The ability to induce Ab responses to pathogens while maintaining the quiescence of autoreactive cells is an important aspect of immune tolerance. During activation of TLR4, dendritic cells (DCs) and macrophages (MFs) repress autoantibody production through their secretion of IL-6 and soluble CD40L (sCD40L). These soluble mediators selectively repress B cells chronically exposed to Ag, but not naive cells, suggesting a means to maintain tolerance during TLR4 stimulation, yet allow immunity. In this study, we identify TNF-α as a third repressive factor, which together with IL-6 and CD40L account for nearly all the repression conferred by DCs and MFs. Similar to IL-6 and sCD40L, TNF-α did not alter B cell proliferation or survival. Instead, it reduced the number of Ab-secreting cells. To address whether the soluble mediators secreted by DCs and MFs functioned in vivo, we generated mice lacking IL-6, CD40L, and TNF-α. Compared to wild-type mice, these mice showed prolonged anti-nuclear Ab responses following TLR4 stimulation. Furthermore, adoptive transfer of autoreactive B cells into chimeric IL-6(-/-) × CD40L(-/-) × TNF-α(-/-) mice showed that preplasma cells secreted autoantibodies independent of germinal center formation or extrafollicular foci. These data indicate that in the absence of genetic predisposition to autoimmunity, loss of endogenous IL-6, CD40L, and TNF-α promotes autoantibody secretion during TLR4 stimulation.


Assuntos
Autoanticorpos/biossíntese , Células Dendríticas/imunologia , Tolerância Imunológica , Macrófagos/imunologia , Plasmócitos/imunologia , Células-Tronco/imunologia , Transferência Adotiva , Animais , Antígenos Nucleares/genética , Antígenos Nucleares/imunologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Ligante de CD40/deficiência , Células Cultivadas , Células Dendríticas/metabolismo , Tolerância Imunológica/genética , Interleucina-6/deficiência , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Camundongos Knockout , Camundongos Transgênicos , Plasmócitos/metabolismo , Plasmócitos/transplante , Quimera por Radiação/imunologia , Células-Tronco/metabolismo , Receptor 4 Toll-Like/fisiologia , Fator de Necrose Tumoral alfa/deficiência
18.
J Immunol ; 189(8): 3859-68, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22984080

RESUMO

To maintain tolerance, autoreactive B cells must regulate signal transduction from the BCR and TLRs. We recently identified that dendritic cells and macrophages regulate autoreactive cells during TLR4 activation by releasing IL-6 and soluble CD40 ligand (sCD40L). These cytokines selectively repress Ab secretion from autoreactive, but not antigenically naive, B cells. How IL-6 and sCD40L repress autoantibody production is unknown. In this work, we show that IL-6 and sCD40L are required for low-affinity/avidity autoreactive B cells to maintain tolerance through a mechanism involving receptor cross-talk between the BCR, TLR4, and the IL-6R or CD40. We show that acute signaling through IL-6R or CD40 integrates with chronic BCR-mediated ERK activation to restrict p-ERK from the nucleus and represses TLR4-induced Blimp-1 and XBP-1 expression. Tolerance is disrupted in 2-12H/MRL/lpr mice where IL-6 and sCD40L fail to spatially restrict p-ERK and fail to repress TLR4-induced Ig secretion. In the case of CD40, acute signaling in B cells from 2-12H/MRL/lpr mice is intact, but the chronic activation of p-ERK emanating from the BCR is attenuated. Re-establishing chronically active ERK through retroviral expression of constitutively active MEK1 restores tolerance upon sCD40L, but not IL-6, stimulation, indicating that regulation by IL-6 requires another signaling effector. These data define the molecular basis for the regulation of low-affinity autoreactive B cells during TLR4 stimulation; they explain how autoreactive but not naive B cells are repressed by IL-6 and sCD40L; and they identify B cell defects in lupus-prone mice that lead to TLR4-induced autoantibody production.


Assuntos
Autoanticorpos/biossíntese , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Nefrite Lúpica/metabolismo , Receptor Cross-Talk/imunologia , Receptor 4 Toll-Like/fisiologia , Animais , Subpopulações de Linfócitos B/patologia , Antígenos CD40/metabolismo , Ligante de CD40/metabolismo , Núcleo Celular/enzimologia , Núcleo Celular/metabolismo , Células Cultivadas , Técnicas de Cocultura , Feminino , Tolerância Imunológica/genética , Nefrite Lúpica/enzimologia , Nefrite Lúpica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Camundongos Transgênicos , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Transporte Proteico/genética , Transporte Proteico/imunologia , Receptores de Antígenos de Linfócitos B/fisiologia , Receptores de Interleucina-6/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia
19.
Psychol Health Med ; 19(5): 525-35, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24102547

RESUMO

Health anxiety is a persistent fear of illness or disease that often involves the misinterpretation of bodily symptoms as signs of serious illness. Evidence shows that health anxiety affects a proportion of women following a diagnosis of breast cancer, but there are some limitations to how health anxiety has been measured. The objectives of this study were to (1) provide an estimate of clinically elevated health anxiety in women after a diagnosis of breast cancer using a validated measure appropriate for medical populations and (2) understand patient, disease, and anxiety/vulnerability variables that predict health anxiety in this group. Canadian women (n = 137) diagnosed with breast cancer within the past five years completed an online survey measuring health anxiety, along with patient, disease, and anxiety/vulnerability variables. Clinically significant health anxiety was reported by 23.4% of the sample. The regression model revealed that younger age, more advanced stage of breast cancer, increased cognitive anxiety sensitivity, and greater body vigilance were significant unique predictors of health anxiety. These findings highlight that a proportion of women report substantial health anxiety following breast cancer diagnosis, with a combination of patient, disease, and anxiety/vulnerability variables associated with the experience. Further research is needed to better understand the impact of health anxiety in this population.


Assuntos
Ansiedade/psicologia , Atitude Frente a Saúde , Neoplasias da Mama/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade
20.
ACS Omega ; 9(1): 1320-1326, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222634

RESUMO

Carbon nanodots (CDs) have drawn significant attention for their potential uses in diagnostic and therapeutic applications due to their small size, tissue biocompatibility, stable photoluminescence, and modifiable surface groups. However, the effect of cargo molecules on CD photoluminescence and their ability to interact with tissues are not fully understood. Our previous work has shown that CDs produced from the acidic oxidation of carbon nanopowder can bind to mineralized bone with high affinity and specificity in a zebrafish animal model system. Using this model, we investigated the impact of loading Cy5 and biotin cargo on CDs' photoluminescence and bone-binding properties. We report that CD cargo loading alters CD photoluminescence in a pH- and cargo-dependent manner without interfering with the CDs' bone binding properties. In a reciprocal analysis, we show that cargo loading of CDs does not affect the cargo's fluorescence. Significantly, CDs do not trigger nitric oxide production in a mouse macrophage assay, suggesting that they are noninflammatory. Together, these results further support the development of carbon nanopowder-derived CDs for the precise delivery of therapeutic agents to bone tissue.

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