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Lightning flashes have been observed by a number of missions that visited or flew by Jupiter over the past several decades. Imagery led to a flash rate estimate of about 4 × 10-3 flashes per square kilometre per year (refs. 1,2). The spatial extent of Voyager flashes was estimated to be about 30 kilometres (half-width at half-maximum intensity, HWHM), but the camera was unlikely to have detected the dim outer edges of the flashes, given its weak response to the brightest spectral line of Jovian lightning emission, the 656.3-nanometre Hα line of atomic hydrogen1,3-6. The spatial resolution of some cameras allowed investigators to confirm 22 flashes with HWHM greater than 42 kilometres, and to estimate one with an HWHM of 37 to 45 kilometres (refs. 1,7-9). These flashes, with optical energies comparable to terrestrial 'superbolts'-of (0.02-1.6) × 1010 joules-have been interpreted as tracers of moist convection originating near the 5-bar level of Jupiter's atmosphere (assuming photon scattering from points beneath the clouds)1-3,7,8,10-12. Previous observations of lightning have been limited by camera sensitivity, distance from Jupiter and long exposures (about 680 milliseconds to 85 seconds), meaning that some measurements were probably superimposed flashes reported as one1,2,7,9,10,13. Here we report optical observations of lightning flashes by the Juno spacecraft with energies of approximately 105-108 joules, flash durations as short as 5.4 milliseconds and inter-flash separations of tens of milliseconds, with typical terrestrial energies. The flash rate is about 6.1 × 10-2 flashes per square kilometre per year, more than an order of magnitude greater than hitherto seen. Several flashes are of such small spatial extent that they must originate above the 2-bar level, where there is no liquid water14,15. This implies that multiple mechanisms for generating lightning on Jupiter need to be considered for a full understanding of the planet's atmospheric convection and composition.
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The Juno spacecraft, which is in a polar orbit around Jupiter, is providing direct measurements of the planet's magnetic field close to its surface1. A recent analysis of observations of Jupiter's magnetic field from eight (of the first nine) Juno orbits has provided a spherical-harmonic reference model (JRM09)2 of Jupiter's magnetic field outside the planet. This model is of particular interest for understanding processes in Jupiter's magnetosphere, but to study the field within the planet and thus the dynamo mechanism that is responsible for generating Jupiter's main magnetic field, alternative models are preferred. Here we report maps of the magnetic field at a range of depths within Jupiter. We find that Jupiter's magnetic field is different from all other known planetary magnetic fields. Within Jupiter, most of the flux emerges from the dynamo region in a narrow band in the northern hemisphere, some of which returns through an intense, isolated flux patch near the equator. Elsewhere, the field is much weaker. The non-dipolar part of the field is confined almost entirely to the northern hemisphere, so there the field is strongly non-dipolar and in the southern hemisphere it is predominantly dipolar. We suggest that Jupiter's dynamo, unlike Earth's, does not operate in a thick, homogeneous shell, and we propose that this unexpected field morphology arises from radial variations, possibly including layering, in density or electrical conductivity, or both.
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Lightning has been detected on Jupiter by all visiting spacecraft through night-side optical imaging and whistler (lightning-generated radio waves) signatures1-6. Jovian lightning is thought to be generated in the mixed-phase (liquid-ice) region of convective water clouds through a charge-separation process between condensed liquid water and water-ice particles, similar to that of terrestrial (cloud-to-cloud) lightning7-9. Unlike terrestrial lightning, which emits broadly over the radio spectrum up to gigahertz frequencies10,11, lightning on Jupiter has been detected only at kilohertz frequencies, despite a search for signals in the megahertz range 12 . Strong ionospheric attenuation or a lightning discharge much slower than that on Earth have been suggested as possible explanations for this discrepancy13,14. Here we report observations of Jovian lightning sferics (broadband electromagnetic impulses) at 600 megahertz from the Microwave Radiometer 15 onboard the Juno spacecraft. These detections imply that Jovian lightning discharges are not distinct from terrestrial lightning, as previously thought. In the first eight orbits of Juno, we detected 377 lightning sferics from pole to pole. We found lightning to be prevalent in the polar regions, absent near the equator, and most frequent in the northern hemisphere, at latitudes higher than 40 degrees north. Because the distribution of lightning is a proxy for moist convective activity, which is thought to be an important source of outward energy transport from the interior of the planet16,17, increased convection towards the poles could indicate an outward internal heat flux that is preferentially weighted towards the poles9,16,18. The distribution of moist convection is important for understanding the composition, general circulation and energy transport on Jupiter.
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Interleukin 17 receptor E (IL-17RE) is an orphan receptor of the IL-17 receptor family. Here we show that IL-17RE is a receptor specific to IL-17C and has an essential role in host mucosal defense against infection. IL-17C activated downstream signaling through IL-17RE-IL-17RA complex for the induction of genes encoding antibacterial peptides as well as proinflammatory molecules. IL-17C was upregulated in colon epithelial cells during infection with Citrobacter rodentium and acted in synergy with IL-22 to induce the expression of antibacterial peptides in colon epithelial cells. Loss of IL-17C-mediated signaling in IL-17RE-deficient mice led to lower expression of genes encoding antibacterial molecules, greater bacterial burden and early mortality during infection. Together our data identify IL-17RE as a receptor of IL-17C that regulates early innate immunity to intestinal pathogens.
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Infecciones por Enterobacteriaceae/inmunología , Inmunidad Mucosa/inmunología , Interleucina-17/metabolismo , Mucosa Intestinal/inmunología , Receptores de Interleucina-17/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/inmunología , Línea Celular , Citrobacter rodentium , Colon/inmunología , Colon/metabolismo , Infecciones por Enterobacteriaceae/genética , Infecciones por Enterobacteriaceae/microbiología , Regulación de la Expresión Génica , Células HEK293 , Células HT29 , Humanos , Inmunidad Mucosa/genética , Interleucinas/metabolismo , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-17/genética , Transducción de Señal , Interleucina-22RESUMEN
The heterodimeric cytokine interleukin 27 (IL-27) signals through the IL-27Rα subunit of its receptor, combined with gp130, a common receptor chain used by several cytokines, including IL-6. Notably, the IL-27 subunits p28 (IL-27p28) and EBI3 are not always expressed together, which suggests that they may have unique functions. Here we show that IL-27p28, independently of EBI3, antagonized cytokine signaling through gp130 and IL-6-mediated production of IL-17 and IL-10. Similarly, the ability to generate antibody responses was dependent on the activity of gp130-signaling cytokines. Mice transgenic for expression of IL-27p28 showed a substantial defect in the formation of germinal centers and antibody production. Thus, IL-27p28, as a natural antagonist of gp130-mediated signaling, may be useful as a therapeutic for managing inflammation mediated by cytokines that signal through gp130.
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Receptor gp130 de Citocinas/metabolismo , Interleucinas/metabolismo , Transducción de Señal/inmunología , Animales , Formación de Anticuerpos/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Separación Celular , Receptor gp130 de Citocinas/inmunología , Citocinas/inmunología , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Inmunohistoquímica , Interleucinas/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Antígenos de Histocompatibilidad Menor , Receptores de Citocinas/inmunología , Receptores de Citocinas/metabolismoRESUMEN
We explored knowledge, beliefs, and acceptability of pre-exposure prophylaxis (PrEP) for HIV prevention with reference to stigma among people who inject drugs (PWID) in two predominately rural U.S. states. We conducted interviews with 65 current or former PWID aged 18 years or older and living in Arizona or Indiana. Most (63%) of the interviewees were not aware of PrEP. They often confused PrEP with HIV treatment, and many believed that PrEP was only for sexual risk or gay sexual risk. Once they understood that PrEP was recommended for PWID, the participants held a positive view of PrEP and felt that a once-daily pill was feasible. Experiences of stigma about drug use remained a crucial barrier to accessing healthcare and PrEP. This was often linked with anticipated or expressed homophobia. PrEP interventions among PWID must focus on education and the confluence of stigmas in which PWID find themselves when considering PrEP.
RESUMEN: Exploramos el conocimiento, las creencias y la aceptabilidad de la profilaxis previa a la exposición (PrEP) para la prevención del VIH con referencia al estigma entre las personas que inyectan drogas (PWID) en dos Estados Unidos predominantemente rurales. estados. Realizamos entrevistas con 65 PWID actuales o anteriores de 18 años o más y viviendo en Arizona o Indiana. Más (63%) de los entrevistados no estaban al tanto de la PrEP. A menudo confundieron la PrEP con el tratamiento del VIH, y muchos creían que la PrEP era sólo por riesgo sexual o riesgo sexual gay. Una vez que entendieron que la PrEP se recomendaba para PWID, los participantes tenían una visión positiva de la PrEP y sentían que una vez-píldora diaria era factible. Las experiencias de estigma sobre el consumo de drogas siguieron siendo una barrera crucial para acceder a la atención médica y a la PrEP. Esto a menudo estaba relacionado con la homofobia anticipada o expresada. Las intervenciones de la PrEP entre PWID deben centrarse en la educación y la confluencia de estigmas en los que PWID se encuentra al considerar la PrEP.
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Fármacos Anti-VIH , Infecciones por VIH , Preparaciones Farmacéuticas , Profilaxis Pre-Exposición , Abuso de Sustancias por Vía Intravenosa , Fármacos Anti-VIH/uso terapéutico , Estudios de Factibilidad , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológicoRESUMEN
Cloud-tracked wind observations document the role of eddies in putting momentum into the zonal jets. Chemical tracers, lightning, clouds, and temperature anomalies document the rising and sinking in the belts and zones, but questions remain about what drives the flow between the belts and zones. We suggest an additional role for the eddies, which is to generate waves that propagate both up and down from the cloud layer. When the waves break they deposit momentum and thereby replace the friction forces at solid boundaries that enable overturning circulations on terrestrial planets. By depositing momentum of one sign within the cloud layer and momentum of the opposite sign above and below the clouds, the eddies maintain all components of the circulation, including the stacked, oppositely rotating cells between each belt-zone pair, and the zonal jets themselves.
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BACKGROUND: Community pharmacies are important for health access by rural populations and those who do not have optimum access to the health system, because they provide myriad health services and are found in most communities. This includes the sale of non-prescription syringes, a practice that is legal in the USA in all but two states. However, people who inject drugs (PWID) face significant barriers accessing sterile syringes, particularly in states without laws allowing syringe services programming. To our knowledge, no recent studies of pharmacy-based syringe purchase experience have been conducted in communities that are both rural and urban, and none in the Southwestern US. This study seeks to understand the experience of retail pharmacy syringe purchase in Arizona by PWID. METHODS: An interview study was conducted between August and December 2018 with 37 people living in 3 rural and 2 urban Arizona counties who identified as current or former users of injection drugs. Coding was both a priori and emergent, focusing on syringe access through pharmacies, pharmacy experiences generally, experiences of stigma, and recommendations for harm reduction services delivered by pharmacies. RESULTS: All participants reported being refused syringe purchase at pharmacies. Six themes emerged about syringe purchase: (1) experience of stigma and judgment by pharmacy staff, (2) feelings of internalized stigma, (3) inconsistent sales outcomes at the same pharmacy or pharmacy chain, (4) pharmacies as last resort for syringes, (5) fear of arrest for syringe possession, and (6) health risks resulting from syringe refusal. CONCLUSIONS: Non-prescription syringe sales in community pharmacies are a missed opportunity to improve the health of PWID by reducing syringe sharing and reuse. Yet, current pharmacy syringe sales refusal and stigmatization by staff suggest that pharmacy-level interventions will be necessary to impact pharmacy practice. Lack of access to sterile syringes reinforces health risk behaviors among PWID. Retail syringe sales at pharmacies remain an important, yet barrier-laden, element of a comprehensive public health response to reduce HIV and hepatitis C among PWID. Future studies should test multilevel evidence-based interventions to decrease staff discrimination and stigma and increase syringe sales.
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Adquisición en Grupo/legislación & jurisprudencia , Reducción del Daño , Compartición de Agujas/legislación & jurisprudencia , Farmacias/legislación & jurisprudencia , Abuso de Sustancias por Vía Intravenosa/rehabilitación , Jeringas/provisión & distribución , Adulto , Anciano , Arizona , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Accesibilidad a los Servicios de Salud/legislación & jurisprudencia , Hepatitis C/prevención & control , Hepatitis C/transmisión , Humanos , Entrevista Psicológica , Masculino , Persona de Mediana Edad , Estigma Social , Adulto JovenRESUMEN
The latitude-altitude map of ammonia mixing ratio shows an ammonia-rich zone at 0-5°N, with mixing ratios of 320-340 ppm, extending from 40-60 bars up to the ammonia cloud base at 0.7 bars. Ammonia-poor air occupies a belt from 5-20°N. We argue that downdrafts as well as updrafts are needed in the 0-5°N zone to balance the upward ammonia flux. Outside the 0-20°N region, the belt-zone signature is weaker. At latitudes out to ±40°, there is an ammonia-rich layer from cloud base down to 2 bars which we argue is caused by falling precipitation. Below, there is an ammonia-poor layer with a minimum at 6 bars. Unanswered questions include how the ammonia-poor layer is maintained, why the belt-zone structure is barely evident in the ammonia distribution outside 0-20°N, and how the internal heat is transported through the ammonia-poor layer to the ammonia cloud base.
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EXECUTIVE SUMMARY: Shifting healthcare market forces and regulation have exerted near-constant pressure on U.S. academic health centers (AHCs) attempting to successfully execute their traditional tripartite mission. A governance structure and organizational alignment that works well under one set of conditions is rarely optimal when conditions change. Thus, the degree and type of alignment of an AHC's clinical, educational, and faculty practice organizations have changed regularly within the sector, typically landing near one end or the other on a continuum from fully aligned with centralized governance to largely independent with separate governance. The authors examine the case of Georgia Regents University and Health System in this context. In step with industry trends, the institution's governance structure swung from fully aligned/centralized governance in the early 1990s to essentially separate and decentralized by 2000. In 2010, the Georgia Regents University organizations achieved rapid realignment by creating a governance structure of sufficient strength and flexibility to absorb and adjust to continuing external upheaval. The hospitals, clinics, and physician-faculty practice group were combined into one integrated health system, then aligned with the university to form the state's only public AHC under aligned, but distinct, corporate and management structures. The years since reorganization have seen significant growth in patient volumes and complexity, improved service quality, and enhanced faculty physician satisfaction, while also significantly increasing economic contributions from the health system to the academic mission. This case study offers observations and lessons learned that may be useful to other higher education institutions considering reorganization.
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Atención a la Salud/organización & administración , Universidades/organización & administración , Estudios de Seguimiento , HumanosRESUMEN
Venous cystic adventitial disease is an exceedingly rare vascular disorder, with 12 cases reported in the past decade. A 60-year-old woman presented with a painful, palpable groin mass without leg swelling. She was initially thought to have a nonreducible inguinal hernia. A computed tomography scan was obtained that revealed a cystic mass involving the right common femoral vein. Previous imaging revealed that the mass had enlarged over time. In the operating room, the cyst wall was excised without compromising vein integrity. The patient had an uneventful recovery and her pain resolved. We review the presentation, diagnosis, and treatment of this condition. We believe that the rapid evolution of this lesion suggests that an unknown inciting factor triggers its onset and growth.
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Adventicia , Quistes/diagnóstico , Vena Femoral , Enfermedades Vasculares/diagnóstico , Adventicia/diagnóstico por imagen , Adventicia/cirugía , Quistes/etiología , Quistes/cirugía , Progresión de la Enfermedad , Femenino , Vena Femoral/diagnóstico por imagen , Vena Femoral/cirugía , Ingle , Humanos , Persona de Mediana Edad , Flebografía/métodos , Tomografía Computarizada por Rayos X , Ultrasonografía , Enfermedades Vasculares/etiología , Enfermedades Vasculares/cirugíaRESUMEN
Costimulatory molecules regulate the functional outcome of T cell activation, and disturbance of the balance between activating and inhibitory signals results in increased susceptibility to infection or the induction of autoimmunity. Similar to the well-characterized CD28/CTLA-4 costimulatory pathway, a newly emerging pathway consisting of CD226 and T cell Ig and ITIM domain (TIGIT) has been associated with susceptibility to multiple autoimmune diseases. In this study, we examined the role of the putative coinhibitory molecule TIGIT and show that loss of TIGIT in mice results in hyperproliferative T cell responses and increased susceptibility to autoimmunity. TIGIT is thought to indirectly inhibit T cell responses by the induction of tolerogenic dendritic cells. By generating an agonistic anti-TIGIT Ab, we demonstrate that TIGIT can inhibit T cell responses directly independent of APCs. Microarray analysis of T cells stimulated with agonistic anti-TIGIT Ab revealed that TIGIT can act directly on T cells by attenuating TCR-driven activation signals.
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Inhibidores de Crecimiento/fisiología , Activación de Linfocitos/inmunología , Receptores Inmunológicos/fisiología , Transducción de Señal/inmunología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Proliferación Celular , Células Cultivadas , Cricetinae , Cricetulus , Regulación hacia Abajo/inmunología , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Predisposición Genética a la Enfermedad , Inhibidores de Crecimiento/biosíntesis , Inhibidores de Crecimiento/deficiencia , Inmunosupresores/metabolismo , Inmunosupresores/farmacología , Activación de Linfocitos/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Datos de Secuencia Molecular , Receptores Inmunológicos/biosíntesis , Receptores Inmunológicos/deficiencia , Transducción de Señal/genética , Linfocitos T/citología , Linfocitos T/metabolismoRESUMEN
IL-27 is a cytokine that regulates Th function during autoimmune and pathogen-induced immune responses. Although previous studies have shown that regulatory T cells (Tregs) express the IL-27R, and that IL-27 inhibits forkhead box P3 upregulation in vitro, little is known about how IL-27 influences Tregs in vivo. The studies presented in this article show that mice that overexpress IL-27 had decreased Treg frequencies and developed spontaneous inflammation. Although IL-27 did not cause mature Tregs to downregulate forkhead box P3, transgenic overexpression in vivo limited the size of a differentiating Treg population in a bone marrow chimera model, which correlated with reduced production of IL-2, a vital cytokine for Treg maintenance. These data identify an indirect role for IL-27 in shaping the Treg pool.
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Diferenciación Celular/inmunología , Inhibidores de Crecimiento/fisiología , Interleucinas/fisiología , Subunidades de Proteína/fisiología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Trasplante de Médula Ósea/inmunología , Trasplante de Médula Ósea/patología , Diferenciación Celular/genética , Células Cultivadas , Femenino , Inhibidores de Crecimiento/biosíntesis , Inhibidores de Crecimiento/genética , Inflamación/genética , Inflamación/inmunología , Inflamación/patología , Interleucina-2/antagonistas & inhibidores , Interleucina-2/biosíntesis , Interleucinas/biosíntesis , Interleucinas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Antígenos de Histocompatibilidad Menor , Subunidades de Proteína/biosíntesis , Subunidades de Proteína/genética , Quimera por Radiación/inmunología , Receptores de Citocinas/biosíntesis , Receptores de Citocinas/genética , Receptores de Citocinas/fisiología , Linfocitos T Reguladores/patologíaRESUMEN
Pseudoaneurysms of the common carotid arteries are rare and have been associated with both penetrating and blunt trauma. Intervention is warranted in most cases to avert the sequelae of rupture or embolization. Treatments are tailored to the specific patient on a case by case basis. This report describes an unusual case of common carotid artery pseudoaneurysm after minor blunt trauma and reviews the diagnostic and treatment modalities available.
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Aneurisma Falso/cirugía , Traumatismos de las Arterias Carótidas/cirugía , Arteria Carótida Común/cirugía , Procedimientos Quirúrgicos Vasculares , Lesiones del Sistema Vascular/cirugía , Heridas no Penetrantes/cirugía , Adulto , Aneurisma Falso/diagnóstico , Traumatismos de las Arterias Carótidas/diagnóstico , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/patología , Femenino , Humanos , Angiografía por Resonancia Magnética , Resultado del Tratamiento , Ultrasonografía Doppler Dúplex , Lesiones del Sistema Vascular/diagnóstico , Heridas no Penetrantes/diagnósticoRESUMEN
BACKGROUND: Devastating neurologic ischemic episodes, such as stroke and deafness, have occurred in patients undergoing shoulder surgery in the beach chair position. We hypothesized that awake patients would be able to avoid significant cerebral deoxygenation events (CDEs) compared with anesthetized patients when procedures were performed in the beach chair position. MATERIALS AND METHODS: Sixty patients underwent elective shoulder surgery in the beach chair position. Thirty patients underwent an interscalene block and monitored sedation (awake group); 30 patients underwent general anesthesia (asleep group). Cerebral oxygenation saturation (Scto2) was measured during the procedure. Scto2 values below critical thresholds were defined as CDEs and treated. RESULTS: Baseline mean arterial pressure and Scto2 values were lower in the asleep group during the operation (P < .0001). A higher incidence of CDEs was seen in the asleep group (56.7% vs 0% awake group), and more CDEs were seen per patient (2.97 in asleep vs 0 awake, P < .0001). Scto2 below a threshold value of 55% was seen in 23.3% in the asleep group vs 3.3% in the awake group. A total of 89 combined desaturation events were documented in the asleep vs 1 in the awake group (P < .0001). CONCLUSIONS: Patients in the beach chair position treated with regional anesthesia and sedation had almost no cerebral desaturation events, unlike patients who had general anesthesia. Avoidance of general anesthesia in the beach chair position may reduce the risk of ischemic neurologic injury.
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Anestesia de Conducción/métodos , Anestesia General/métodos , Distinciones y Premios , Oximetría/métodos , Posicionamiento del Paciente/métodos , Articulación del Hombro/cirugía , Accidente Cerebrovascular/prevención & control , Artroscopía/métodos , Encéfalo/irrigación sanguínea , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Posicionamiento del Paciente/efectos adversos , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Biomechanical analysis of biceps tenodesis procedures has historically focused on load to failure models. Minimal data exists for the analysis of biomechanical strain properties of the biceps tendon in a sub-failure, physiologic cadaver model. HYPOTHESIS: Tendon strain characteristics are different between bony and soft tissue tenodesis surgery, and the soft tissue tenodesis procedure reproduces a strain pattern more similar to the native biceps tendon. METHODS: Eight fresh frozen cadaver upper extremities were mounted onto a custom device that controls shoulder abduction and rotation. Strain on the tendon was measured using a differential variable reluctance transducer as the arm was moved through cycles of abduction and external rotation. Each arm was mounted once, and all 3 testing procedures were performed on each of the 8 specimens. Statistical analysis was completed using ANOVA, followed by multiple comparisons with Bonferroni correction. RESULTS: The bony tenodesis model placed higher strain on the biceps tendon than the soft tissue tenodesis (p = 0.025). Also, the bony tenodesis model increased the strain on the biceps tendon when compared to the native tendon (p = 0.031). In contrast, the soft tissue tenodesis did not significantly alter strain when compared to the native tendon (p = 0.089). CONCLUSION: The soft tissue tenodesis procedure better maintained the native strain environment when compared to the bony tenodesis using an interference screw. Due to this closer approximation of native biceps tendon biomechanics, the soft tissue procedure may be more preferable clinically than the bony tenodesis. LEVEL OF EVIDENCE: 1, Controlled Laboratory Study.
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Tenodesis/métodos , Anciano , Fenómenos Biomecánicos , Huesos , Cadáver , Humanos , Masculino , Persona de Mediana Edad , Músculo EsqueléticoRESUMEN
OBJECTIVE: CD28 and inducible T cell costimulator (ICOS) appear to have nonredundant roles in T cell activation and adaptive immunity. We undertook this study to characterize in vitro and in vivo the therapeutic potential of acazicolcept (ALPN-101), an Fc fusion protein of a human variant ICOS ligand (ICOSL) domain designed to inhibit both CD28 and ICOS costimulation, in inflammatory arthritis. METHODS: Acazicolcept was compared in vitro with inhibitors of either the CD28 or ICOS pathways (abatacept and belatacept [CTLA-4Ig], prezalumab [anti-ICOSL monoclonal antibody]) in receptor binding and signaling assays, and in a collagen-induced arthritis (CIA) model. Acazicolcept was also compared in cytokine and gene expression assays of peripheral blood mononuclear cells (PBMCs) from healthy donors or rheumatoid arthritis (RA) or psoriatic arthritis (PsA) patients stimulated with artificial antigen-presenting cells (APCs) expressing CD28 and ICOS ligands*. RESULTS: Acazicolcept bound CD28 and ICOS, prevented ligand binding, and inhibited human T cell functional interactions, matching or exceeding the activity of CD28 or ICOS costimulatory single-pathway inhibitors tested individually or in combination. Acazicolcept administration significantly reduced disease in the CIA model and more potently than abatacept. Acazicolcept also inhibited proinflammatory cytokine production from stimulated PBMCs in cocultures with artificial APCs and demonstrated unique effects on gene expression distinct from those induced by abatacept, prezalumab, or a combination of both. CONCLUSION: Both CD28 and ICOS signaling play critical roles in inflammatory arthritis. Therapeutic agents such as acazicolcept that coinhibit both ICOS and CD28 signaling may mitigate inflammation and/or disease progression in RA and PsA more effectively than inhibitors of either pathway alone.
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Artritis Psoriásica , Artritis Reumatoide , Humanos , Antígenos CD28/metabolismo , Abatacept/farmacología , Abatacept/uso terapéutico , Leucocitos Mononucleares/metabolismo , Ligandos , Proteína Coestimuladora de Linfocitos T Inducibles , Linfocitos T , Factores Inmunológicos , Artritis Reumatoide/tratamiento farmacológico , Anticuerpos Monoclonales/farmacología , CitocinasRESUMEN
Members of the CD28 family play important roles in regulating T-cell functions and share a common gene structure profile. We have identified VSTM3 as a protein whose gene structure matches that of the other CD28 family members. This protein (also known as TIGIT and WUCAM) has been previously shown to affect immune responses and is expressed on NK cells, activated and memory T cells, and Tregs. The nectin-family proteins CD155 and CD112 serve as counter-structures for VSTM3, and CD155 and CD112 also bind to the activating receptor CD226 on T cells and NK cells. Hence, this group of interacting proteins forms a network of molecules similar to the well-characterized CD28-CTLA-4-CD80-CD86 network. In the same way that soluble CTLA-4 can be used to block T-cell responses, we show that soluble Vstm3 attenuates T-cell responses in vitro and in vivo. Moreover, animals deficient in Vstm3 are more sensitive to autoimmune challenges indicating that this new member of the CD28 family is an important regulator of T-cell responses.
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Antígenos CD28/inmunología , Receptores Inmunológicos/inmunología , Linfocitos T/inmunología , Animales , Enfermedades Autoinmunes/inmunología , Células Cultivadas , Células Dendríticas/inmunología , Humanos , Ratones , Ratas , Receptores Inmunológicos/deficiencia , Linfocitos T/químicaRESUMEN
The Src family kinase Lck has been shown to be crucial in T cell signaling and development. However, its role in Th effector functions is not well understood. Lck has previously been shown to play a role in the cytokine expression of Th2 cells, but the mechanism by which Lck influences Th2 effector functions is unknown. Using a mouse model, we report that Lck is important in regulating the expression of IL-4 in Th2 skewed cells but is not as necessary for the expression of Th2 cytokines IL-5, IL-10, and IL-13. Furthermore, in the absence of Lck, T-bet and GATA-3 expression is aberrant. Moreover, this atypical expression pattern of T-bet and GATA-3 correlates with increased histone 3 acetylation at the Ifng locus and production of the Th1 cytokine IFN-gamma. We find overexpression of GATA-3 restores IL-4 expression in lck(-/-) Th2 cells; this indicates that the decreased IL-4 expression is due in part to reduced amounts of GATA-3. Taken together, these data imply that Lck mediates Th2 differentiation through effects on T-bet and GATA-3.