Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 94
Filtrar
1.
BMC Cancer ; 24(1): 482, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627648

RESUMEN

BACKGROUND: Therapies for metastatic castration-resistant prostate cancer (mCRPC) include targeting the androgen receptor (AR) with androgen receptor inhibitors (ARIs) and prostate-specific membrane antigen (PSMA). Having the ability to detect AR, AR splice variant 7 (AR-V7), or PSMA in circulating tumor cells (CTCs) or circulating exosomal cell-free RNA (cfRNA) could be helpful to guide selection of the appropriate therapy for each individual patient. The Vortex Biosciences VTX-1 system is a label-free CTC isolation system that enables the detection of the expression of multiple genes in both CTCs and exosomal cfRNA from the same blood sample in patients with mCRPC. Detection of both AR-V7 and PSMA gene expression in both CTCs and cfRNA simultaneously has not yet been reported. METHODS: To characterize the combined VTX-1-AdnaDetect workflow, 22Rv1 cancer cells were spiked into blood from healthy donors and processed with the VTX-1 to mimic patient samples and assess performances (capture efficiency, purity, AR and AR-V7 expression). Then, we collected 19 blood samples from 16 patients with mCRPC and therapeutic resistance to androgen receptor inhibitors (ARIs). Plasma was separated and the plasma-depleted blood was processed further with the VTX-1 to collect CTCs. Both plasma exosomal cfRNA and CTCs were subsequently analyzed for AR, AR-V7, PSMA, and prostate-specific antigen (PSA) mRNA expression using the AdnaTest ProstateCancerPanel AR-V7 assay. RESULTS: AR-V7 expression could be detected in 22Rv1 cells spiked into blood from healthy volunteers as well as in CTCs and plasma-derived exosomal cfRNA from patients with mCRPC by processing blood with the VTX-1 CTC isolation system followed by the AdnaTest ProstateCancerPanel AR-V7 assay. 94.7% of patient blood samples (18/19) had detectable AR expression in either CTCs or exosomal cfRNA (16 in CTCs, 12 in cfRNA). 15.8% of the 19 patient blood samples (3/19) were found to have AR-V7-positive (AR-V7+) CTCs, one of which was also AR-V7+ in the exosomal cfRNA analysis. 42.1% of patient blood samples (8/19) were found to be PSMA positive (PSMA+): 26.3% (5/19) were PSMA+ in the CTC analysis and 31.6% (6/19) were PSMA+ in the exosomal cfRNA analysis. Of those 8 PSMA+ samples, 2 had detectable PSMA only in CTCs, and 3 had detectable PSMA only in exosomal cfRNA. CONCLUSION: VTX-1 enables isolation of CTCs and plasma exosomes from a single blood draw and can be used for detecting AR-V7 and PSMA mRNA in both CTCs and cfRNA in patients with mCRPC and resistance to ARIs. This technology facilitates combining RNA measurements in CTCs and exosomal cfRNA for future studies to develop potentially clinically relevant cancer biomarker detection in blood.


Asunto(s)
Ácidos Nucleicos Libres de Células , Exosomas , Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Antagonistas de Receptores Androgénicos/farmacología , Antagonistas de Receptores Androgénicos/uso terapéutico , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Ácidos Nucleicos Libres de Células/metabolismo , Exosomas/genética , Exosomas/metabolismo , Células Neoplásicas Circulantes/patología , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Isoformas de Proteínas/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , ARN Mensajero/genética
2.
Laryngoscope ; 134(4): 1945-1954, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37767870

RESUMEN

OBJECTIVE: The purpose of this study was to identify risk factors for perioperative complications and long-term morbidity in infants from the neonatal intensive care unit (NICU) presenting for a tracheostomy. METHODS: This single-center retrospective cohort study included infants in the NICU presenting for a tracheostomy from August 2011 to December 2019. Primary outcomes were categorized as either a perioperative complication or long-term morbidity. A severe perioperative complication was defined as having either (1) an intraoperative cardiopulmonary arrest, (2) an intraoperative death, (3) a postoperative cardiopulmonary arrest within 30 days of the procedure, or (4) a postoperative death within 30 days of the procedure. Long-term morbidities included (1) the need for gastrostomy tube placement within the tracheostomy hospitalization and (2) the need for diuretic therapy, pulmonary hypertensive therapy, oxygen, or mechanical ventilation at 12 and 24 months following the tracheostomy. RESULTS: One-hundred eighty-three children underwent a tracheostomy. The mean age at tracheostomy was 16.9 weeks while the mean post-conceptual age at tracheostomy was 49.7 weeks. The incidence of severe perioperative complications was 4.4% (n = 8) with the number of pulmonary hypertension medication classes preoperatively (OR: 3.64, 95% CI: (1.44-8.94), p = 0.005) as a significant risk factor. Approximately 81% of children additionally had a gastrostomy tube placed at the time of the tracheostomy, and 62% were ventilator-dependent 2 years following their tracheostomy. CONCLUSION: Our study provides critical perioperative complications and long-term morbidity data to neonatologists, pediatricians, surgeons, anesthesiologists, and families in the expected course of infants from the NICU presenting for a tracheostomy. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:1945-1954, 2024.


Asunto(s)
Paro Cardíaco , Unidades de Cuidado Intensivo Neonatal , Lactante , Recién Nacido , Niño , Humanos , Estudios Retrospectivos , Traqueostomía/efectos adversos , Traqueostomía/métodos , Hospitalización
3.
Nat Commun ; 14(1): 7745, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38008801

RESUMEN

Vaccines that protect against any H1N1 influenza A virus strain would be advantageous for use in pigs and humans. Here, we try to induce a pan-H1N1 antibody response in pigs by sequential vaccination with antigenically divergent H1N1 strains. Adjuvanted whole inactivated vaccines are given intramuscularly in various two- and three-dose regimens. Three doses of heterologous monovalent H1N1 vaccine result in seroprotective neutralizing antibodies against 71% of a diverse panel of human and swine H1 strains, detectable antibodies against 88% of strains, and sterile cross-clade immunity against two heterologous challenge strains. This strategy outperforms any two-dose regimen and is as good or better than giving three doses of matched trivalent vaccine. Neutralizing antibodies are H1-specific, and the second heterologous booster enhances reactivity with conserved epitopes in the HA head. We show that even the most traditional influenza vaccines can offer surprisingly broad protection if they are administered in an alternative way.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Humanos , Animales , Porcinos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunación
4.
Antimicrob Agents Chemother ; 67(3): e0151422, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36852998

RESUMEN

Anti-SARS-CoV-2 immunoglobulin (human) investigational product (COVID-HIGIV) is a purified immunoglobulin preparation containing SARS-CoV-2 polyclonal antibodies. This single-center clinical trial aimed to characterize the safety and pharmacokinetics of COVID-HIGIV in healthy, adult volunteers. Participants were enrolled to receive one of three doses of COVID-HIGIV (100, 200, 400 mg/kg) or placebo in a 2:2:2:1 randomization scheme. Between 24 December 2020 and 27 July 2021, 28 participants met eligibility and were randomized with 27 of these 28 (96.4%) being administered either COVID-HIGIV (n = 23) or placebo (n = 4). Only one SAE was observed, and it occurred in the placebo group. A total of 18 out of 27 participants (66.7%) reported 50 adverse events (AEs) overall. All COVID-HIGIV-related adverse events were mild or moderate in severity and transient. The most frequent AEs (>5% of participants) reported in the safety population were headache (n = 6, 22.2%), chills (n = 3, 11.1%), increased bilirubin (n = 2, 7.4%), muscle spasms (n = 2, 7.4%), seasonal allergies (n = 2, 7.4%), pyrexia (n = 2, 7.4%), and oropharyngeal pain (n = 2, 7.4%). Using the SARS-CoV-2 binding IgG immunoassay (n = 22, specific for pharmacokinetics), the geometric means of Cmax (AU/mL) for the three COVID-HIGIV dose levels (low to high) were 7.69, 17.02, and 33.27 AU/mL; the average values of Tmax were 7.09, 7.93, and 5.36 h, respectively. The half-life of COVID-HIGIV per dose level was 24 d (583 h), 31 d (753 h), and 26 d (619 h) for the 100 mg/kg, 200 mg/kg, and 400 mg/kg groups, respectively. The safety and pharmacokinetics of COVID-HIGIV support its development as a single-dose regimen for postexposure prophylaxis or treatment of COVID-19.


Asunto(s)
COVID-19 , Humanos , Adulto , SARS-CoV-2 , Anticuerpos Antivirales , Inmunoglobulina G , Administración Intravenosa , Método Doble Ciego
5.
Life (Basel) ; 13(1)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36676159

RESUMEN

(1) Background: Several retrospective observational analyzed treatment outcomes for COVID-19; (2) Methods: Inverse probability of censoring weighting (IPCW) was applied to correct for bias due to informative censoring in database of hospitalized patients who did and did not receive convalescent plasma; (3) Results: When compared with an IPCW analysis, overall mortality was overestimated using an unadjusted Kaplan-Meier curve, and hazard ratios for the older age group compared to the youngest were underestimated using the Cox proportional hazard models and 30-day mortality; (4) Conclusions: An IPCW analysis provided stabilizing weights by hospital admission.

6.
J Sci Food Agric ; 103(4): 2088-2097, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36543748

RESUMEN

BACKGROUND: Buckwheat (Fagopyrum esculentum) is rich in bioactive components. However, many of these components are trapped within cellular structures, making them inaccessible. Buckwheat flour was hydrothermally modified using subcritical water coupled with a flash pressure release (SCWF). The effects of the SCWF parameters (120, 140, and 160 °C and hold times of 0, 15, and 30 min) on the flour's structure, physicochemical, and functional properties were studied relative to the raw flour. RESULTS: Treatment deepened the flour color with increasing processing temperatures and hold times. Starch content remained unchanged though its granular structure was disrupted. SCWF treatments lowered total phenolic content compared with the raw flour, except for 160 °C-30 min, where total phenolic content increased by 12.7%. The corresponding antioxidant activities were found consistent with phenolic content. Soluble and insoluble dietary fiber amounts were not substantially influenced at 120 and 140 °C, whereas treatments at 160 °C (15 and 30 min hold) decreased soluble dietary fiber while increasing insoluble dietary fiber. Protein content increased 70-109% in some treatments, suggesting greater protein accessibility. Water-holding capacity significantly increased for flour treated at 120 °C, whereas only slight improvements occurred at 140 and 160 °C. CONCLUSIONS: Subcritical water flash processing can modify the compositional and functional properties of buckwheat flour depending on the choice of reaction conditions. Observed changes were consistent with alteration of the flour's cellular structure and allow some components to become more accessible. The resulting SCWF-modified buckwheat flours provide new food ingredients for potential use in ready-to-eat foods and spreads with improved health benefits. Published 2022. This article is a U.S. Government work and is in the public domain in the USA.


Asunto(s)
Fagopyrum , Harina , Harina/análisis , Fagopyrum/química , Antioxidantes/metabolismo , Fenoles/análisis , Fibras de la Dieta/análisis
7.
Aging Cell ; 20(9): e13441, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34346557

RESUMEN

The identification and validation of drugs that promote health during aging ("geroprotectors") are key to the retardation or prevention of chronic age-related diseases. Here, we found that most of the established pro-longevity compounds shown to extend lifespan in model organisms also alter extracellular matrix gene expression (i.e., matrisome) in human cell lines. To harness this observation, we used age-stratified human transcriptomes to define the age-related matreotype, which represents the matrisome gene expression pattern associated with age. Using a "youthful" matreotype, we screened in silico for geroprotective drug candidates. To validate drug candidates, we developed a novel tool using prolonged collagen expression as a non-invasive and in-vivo surrogate marker for Caenorhabditis elegans longevity. With this reporter, we were able to eliminate false-positive drug candidates and determine the appropriate dose for extending the lifespan of C. elegans. We improved drug uptake for one of our predicted compounds, genistein, and reconciled previous contradictory reports of its effects on longevity. We identified and validated new compounds, tretinoin, chondroitin sulfate, and hyaluronic acid, for their ability to restore age-related decline of collagen homeostasis and increase lifespan. Thus, our innovative drug screening approach-employing extracellular matrix homeostasis-facilitates the discovery of pharmacological interventions promoting healthy aging.


Asunto(s)
Antiinflamatorios/farmacología , Caenorhabditis elegans/efectos de los fármacos , Hipoglucemiantes/farmacología , Inmunosupresores/farmacología , Longevidad/efectos de los fármacos , Animales , Evaluación Preclínica de Medicamentos
8.
Food Res Int ; 147: 110453, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34399455

RESUMEN

Flatulence is one barrier to pulse consumption for many people. Therefore, we examined how processing affects gas production by the microbiome in three classes of pulses. Processing did not affect gas production from Navy beans. However, in Pardina lentils and green peas, (-1.9 ± 0.3 mL/24 h, p < 0.001; -2.3 ± 0.3 mL/24 h, p < 0.001, respectively). In Pardina lentils and green peas, germination diminished carbohydrate utilization by the microbiome compared with unprocessed samples. In Pardina lentils germination reduced abundance germination resulted in the greatest reduction in gas production among six processing methods of amplicon sequence variants (ASVs) from Bacteroides and Lachnospiraceae and reduced propionate production compared with unprocessed samples. In green peas, germination reduced ASVs from Lachnospiraceae, including one from Roseburia, and reduced proportion of butyrate production during fermentation. Three ASVs from Clostridium sensu stricto (cluster 1), Megasphaera elsdenii, and unclassified Veillonellaceae, were strongly associated with increased gas production across all samples (ρ = 0.67-0.69, p < 0.001). This study showed that processing can reduce gas production by the microbiome in some pulses, but also reduces saccharolytic fermentation and production of beneficial microbial metabolites.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Bacterias/genética , Heces , Fermentación , Humanos
9.
Vaccines (Basel) ; 9(6)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204268

RESUMEN

Fc-dependent effector functions are an important determinant of the in vivo potency of therapeutic antibodies. Effector function is determined by the combination of FcRs bound by the antibody and the cell expressing the relevant FcRs, leading to antibody-dependent cellular cytotoxicity (ADCC). A number of ADCC assays have been developed; however, they suffer from limitations in terms of throughput, reproducibility, and in vivo relevance. Existing assays measure NK cell-mediated ADCC activity; however, studies suggest that macrophages mediate the effector function of many antibodies in vivo. Here, we report the development of a macrophage-based ADCC assay that relies on luciferase expression in target cells as a measure of live cell number. In the presence of primary mouse macrophages and specific antibodies, loss of luciferase signal serves as a surrogate for ADCC-dependent killing. We show that the assay functions for a variety of mouse and human isotypes with a model antigen/antibody complex in agreement with the known effector function of the isotypes. We also use this assay to measure the activity of a number of influenza-specific antibodies and show that the assay correlates well with the known in vivo effector functions of these antibodies.

10.
Percept Mot Skills ; 128(5): 1932-1958, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34107802

RESUMEN

While prior research has generally found Outdoor Education Programs (OEPs) to be beneficial to adolescents' self-efficacy, we sought to conduct a meta-analytic review of prior studies in this area in order to pinpoint the key elements to OEPs' effectiveness. Following Cooper's guidelines for synthesis research and meta-analysis, we searched six electronic databases for relevant articles: PubMed, Sciencedirect, Medline, PsycArticles, and Behavioral Sciences Collection of EBSCO, and Eric. Selection criteria were: Populations, Interventions, Comparators, Outcomes, Study Design (PICOS), and Methodological Index for Non-randomized Studies (MINORS). We estimated the effect size of the selected studies with a 95% confidence interval (CI), estimated I-squared (I2) for heterogeneity analysis and analyzed publication bias by Egger's test. After excluding many studies, we reviewed 12 studies with 2,642 participants that were deemed to be eligible for final analysis. We discovered a high level of heterogeneity (I-squared value =82.474) in the findings of the selected studies. Our meta-analyses revealed that adolescents participating in OEPs enhanced their self-efficacy (medium effect size; Hedges's g = 0.597) but this enhancement was moderated by participants' mental health status, the length of the experiments, study groups, and the duration of the intervention. We found no evidence of publication bias (Egger: bias = 2.001, 95% CI = -0.736 to 4.739, p = .137). We discussed our research limitations and the theoretical and practical implications of these findings and made recommendations for future research.


Asunto(s)
Autoeficacia , Adolescente , Humanos
11.
Sci Transl Med ; 13(596)2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34078743

RESUMEN

Broadly neutralizing antibodies are critical for protection against both drifted and shifted influenza viruses. Here, we reveal that first exposure to the 2009 pandemic H1N1 influenza virus recalls memory B cells that are specific to the conserved receptor-binding site (RBS) or lateral patch epitopes of the hemagglutinin (HA) head domain. Monoclonal antibodies (mAbs) generated against these epitopes are broadly neutralizing against H1N1 viruses spanning 40 years of viral evolution and provide potent protection in vivo. Lateral patch-targeting antibodies demonstrated near universal binding to H1 viruses, and RBS-binding antibodies commonly cross-reacted with H3N2 viruses and influenza B viruses. Lateral patch-targeting mAbs were restricted to expressing the variable heavy-chain gene VH3-23 with or without the variable kappa-chain gene VK1-33 and often had a Y-x-R motif within the heavy-chain complementarity determining region 3 to make key contacts with HA. Moreover, lateral patch antibodies that used both VH3-23 and VK1-33 maintained neutralizing capability with recent pH1N1 strains that acquired mutations near the lateral patch. RBS-binding mAbs used a diverse repertoire but targeted the RBS epitope similarly and made extensive contacts with the major antigenic site Sb. Together, our data indicate that RBS- and lateral patch-targeting clones are abundant within the human memory B cell pool, and universal vaccine strategies should aim to drive antibodies against both conserved head and stalk epitopes.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Anticuerpos ampliamente neutralizantes , Epítopos , Glicoproteínas Hemaglutininas del Virus de la Influenza , Hemaglutininas , Humanos , Subtipo H3N2 del Virus de la Influenza A
12.
Mayo Clin Proc ; 96(5): 1262-1275, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33958057

RESUMEN

To determine the effect of COVID-19 convalescent plasma on mortality, we aggregated patient outcome data from 10 randomized clinical trials, 20 matched control studies, 2 dose-response studies, and 96 case reports or case series. Studies published between January 1, 2020, and January 16, 2021, were identified through a systematic search of online PubMed and MEDLINE databases. Random effects analyses of randomized clinical trials and matched control data demonstrated that patients with COVID-19 transfused with convalescent plasma exhibited a lower mortality rate compared with patients receiving standard treatments. Additional analyses showed that early transfusion (within 3 days of hospital admission) of higher titer plasma is associated with lower patient mortality. These data provide evidence favoring the efficacy of human convalescent plasma as a therapeutic agent in hospitalized patients with COVID-19.


Asunto(s)
COVID-19/terapia , COVID-19/mortalidad , Humanos , Inmunización Pasiva/métodos , Mortalidad , SARS-CoV-2/inmunología , Tiempo de Tratamiento , Sueroterapia para COVID-19
13.
J Clin Invest ; 131(12)2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33956668

RESUMEN

Severe asthma remains challenging to manage and has limited treatment options. We have previously shown that targeting smooth muscle integrin α5ß1 interaction with fibronectin can mitigate the effects of airway hyperresponsiveness by impairing force transmission. In this study, we show that another member of the integrin superfamily, integrin α2ß1, is present in airway smooth muscle and capable of regulating force transmission via cellular tethering to the matrix protein collagen I and, to a lesser degree, laminin-111. The addition of an inhibitor of integrin α2ß1 impaired IL-13-enhanced contraction in mouse tracheal rings and human bronchial rings and abrogated the exaggerated bronchoconstriction induced by allergen sensitization and challenge. We confirmed that this effect was not due to alterations in classic intracellular myosin light chain phosphorylation regulating muscle shortening. Although IL-13 did not affect surface expression of α2ß1, it did increase α2ß1-mediated adhesion and the level of expression of an activation-specific epitope on the ß1 subunit. We developed a method to simultaneously quantify airway narrowing and muscle shortening using 2-photon microscopy and demonstrated that inhibition of α2ß1 mitigated IL-13-enhanced airway narrowing without altering muscle shortening by impairing the tethering of muscle to the surrounding matrix. Our data identified cell matrix tethering as an attractive therapeutic target to mitigate the severity of airway contraction in asthma.


Asunto(s)
Asma/metabolismo , Colágeno Tipo I/metabolismo , Integrina alfa2beta1/metabolismo , Tráquea/metabolismo , Animales , Asma/patología , Línea Celular , Constricción Patológica/metabolismo , Humanos , Interleucina-13/metabolismo , Ratones
14.
medRxiv ; 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34031663

RESUMEN

Antibodies (Abs) are essential for the host immune response against SARS-CoV-2, and all the vaccines developed so far have been designed to induce Abs targeting the SARS-CoV-2 spike. Many studies have examined Ab responses in the blood from vaccinated and infected individuals. However, since SARS-CoV-2 is a respiratory virus, it is also critical to understand the mucosal Ab responses at the sites of initial virus exposure. Here, we examined plasma versus saliva Ab responses in vaccinated and convalescent patients. Although saliva levels were significantly lower, a strong correlation was observed between plasma and saliva total Ig levels against all SARS-CoV-2 antigens tested. Virus-specific IgG1 responses predominated in both saliva and plasma, while a lower prevalence of IgM and IgA1 Abs was observed in saliva. Antiviral activities of plasma Abs were also studied. Neutralization titers against the initial WA1 (D614G), B.1.1.7 (alpha) and B.1.617.2 (delta) strains were similar but lower against the B.1.351 (beta) strain. Spike-specific antibody-dependent cellular phagocytosis (ADCP) activities were also detected and the levels correlated with spike-binding Ig titers. Interestingly, while neutralization and ADCP potencies of vaccinated and convalescent groups were comparable, enhanced complement deposition to spike-specific Abs was noted in vaccinated versus convalescent groups and corresponded with higher levels of IgG1 plus IgG3 among the vaccinated individuals. Altogether, this study demonstrates the detection of Ab responses after vaccination or infection in plasma and saliva that correlate significantly, although Ig isotypic differences were noted. The induced plasma Abs displayed Fab-mediated and Fc-dependent functions with comparable neutralization and ADCP potencies, but a greater capacity to activate complement was elicited upon vaccination.

17.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33593910

RESUMEN

In this study, we utilized a panel of human immunoglobulin (Ig) IgA monoclonal antibodies isolated from the plasmablasts of eight donors after 2014/2015 influenza virus vaccination (Fluarix) to study the binding and functional specificities of this isotype. In this cohort, isolated IgA monoclonal antibodies were primarily elicited against the hemagglutinin protein of the H1N1 component of the vaccine. To compare effector functionalities, an H1-specific subset of antibodies targeting distinct epitopes were expressed as monomeric, dimeric, or secretory IgA, as well as in an IgG1 backbone. When expressed with an IgG Fc domain, all antibodies elicited Fc-effector activity in a primary polymorphonuclear cell-based assay which differs from previous observations that found only stalk-specific antibodies activate the low-affinity FcγRIIIa. However, when expressed with IgA Fc domains, only antibodies targeting the stalk domain showed Fc-effector activity in line with these previous findings. To identify the cause of this discrepancy, we then confirmed that IgG signaling through the high-affinity FcγI receptor was not restricted to stalk epitopes. Since no corresponding high-affinity Fcα receptor exists, the IgA repertoire may therefore be limited to stalk-specific epitopes in the context of Fc receptor signaling.


Asunto(s)
Epítopos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Inmunoglobulina A/inmunología , Fragmentos Fc de Inmunoglobulinas/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Adulto , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Afinidad de Anticuerpos , Sitios de Unión de Anticuerpos , Embrión de Pollo , Microscopía por Crioelectrón , Femenino , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Humanos , Vacunas contra la Influenza/inmunología , Masculino , Neutrófilos/inmunología , Neutrófilos/virología
18.
Sci Rep ; 11(1): 2846, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33531589

RESUMEN

Skeletal muscle Na+ channels possess Ca2+- and calmodulin-binding sites implicated in Nav1.4 current (INa) downregulation following ryanodine receptor (RyR1) activation produced by exchange protein directly activated by cyclic AMP or caffeine challenge, effects abrogated by the RyR1-antagonist dantrolene which itself increased INa. These findings were attributed to actions of consequently altered cytosolic Ca2+, [Ca2+]i, on Nav1.4. We extend the latter hypothesis employing cyclopiazonic acid (CPA) challenge, which similarly increases [Ca2+]i, but through contrastingly inhibiting sarcoplasmic reticular (SR) Ca2+-ATPase. Loose patch clamping determined Na+ current (INa) families in intact native murine gastrocnemius skeletal myocytes, minimising artefactual [Ca2+]i perturbations. A bespoke flow system permitted continuous INa comparisons through graded depolarizing steps in identical stable membrane patches before and following solution change. In contrast to the previous studies modifying RyR1 activity, and imposing control solution changes, CPA (0.1 and 1 µM) produced persistent increases in INa within 1-4 min of introduction. CPA pre-treatment additionally abrogated previously reported reductions in INa produced by 0.5 mM caffeine. Plots of peak current against voltage excursion demonstrated that 1 µM CPA increased maximum INa by ~ 30%. It only slightly decreased half-maximal activating voltages (V0.5) and steepness factors (k), by 2 mV and 0.7, in contrast to the V0.5 and k shifts reported with direct RyR1 modification. These paradoxical findings complement previously reported downregulatory effects on Nav1.4 of RyR1-agonist mediated increases in bulk cytosolic [Ca2+]. They implicate possible local tubule-sarcoplasmic triadic domains containing reduced [Ca2+]TSR in the observed upregulation of Nav1.4 function following CPA-induced SR Ca2+ depletion.


Asunto(s)
Músculo Esquelético/metabolismo , Canal de Sodio Activado por Voltaje NAV1.4/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Animales , Cafeína/farmacología , Agonistas de los Canales de Calcio/farmacología , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Indoles/farmacología , Ratones , Fibras Musculares Esqueléticas , Músculo Esquelético/citología , Músculo Esquelético/efectos de los fármacos , Técnicas de Placa-Clamp , Cultivo Primario de Células , Retículo Sarcoplasmático/efectos de los fármacos , Retículo Sarcoplasmático/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/antagonistas & inhibidores , Sodio/metabolismo , Regulación hacia Arriba/efectos de los fármacos
19.
Int J Part Ther ; 7(3): 1-10, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33604411

RESUMEN

PURPOSE: Patient travel time can cause treatment delays when providers and families decide to seek proton therapy. We examined whether travel distance or referral pattern (domestic versus international) affects time to radiation therapy and subsequent disease outcomes in patients with medulloblastoma at a large academic proton center. PATIENTS AND METHODS: Children with medulloblastoma treated at MD Anderson (MDA) with a protocol of proton beam therapy (PBT) between January 4, 2007, and June 25, 2014, were included in the analysis. The Wilcoxon rank-sum test was used to study the association between time to start of radiation and distance. Classification- and regression-tree analyses were used to explore binary thresholds for continuous covariates (ie, distance). Failure-free survival was defined as the time interval between end of radiation and failure or death. RESULTS: 96 patients were included in the analysis: 17 were international (18%); 19 (20%) were from Houston, Texas; 21 were from other cities inside Texas (21%); and 39 (41%) were from other US states. The median time from surgery to start of radiation was not significantly different for international patients (median = 1.45 months) compared with US patients (median = 1.15 months; P = .13). However, time from surgery to start of radiation was significantly longer for patients residing > 1716 km (> 1066 miles) from MDA (median = 1.31 months) than for patients residing ≤ 1716 km (≤ 1066 miles) from MDA (median = 1.05 months; P = .01). This 1- to 2-week delay (median = 7.8 days) did not affect failure-free survival (hazard ratio = 1.34; P = .43). CONCLUSION: We found that short delays in proton access can exist for patients traveling long distances to proton centers. However, in this study, treatment delays did not affect outcomes. This highlights the appropriateness of PBT in the face of travel coordination. Investment by proton centers in a rigorous intake process is justified to offer timely access to curative PBT.

20.
Nucleic Acids Res ; 49(3): 1345-1363, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33434264

RESUMEN

Enhancers play important roles in controlling gene expression in a choreographed spatial and temporal manner during development. However, it is unclear how these regulatory regions are established during differentiation. Here we investigated the genome-wide binding profile of the forkhead transcription factor FOXK2 in human embryonic stem cells (ESCs) and downstream cell types. This transcription factor is bound to thousands of regulatory regions in human ESCs, and binding at many sites is maintained as cells differentiate to mesendodermal and neural precursor cell (NPC) types, alongside the emergence of new binding regions. FOXK2 binding is generally associated with active histone marks in any given cell type. Furthermore newly acquired, or retained FOXK2 binding regions show elevated levels of activating histone marks following differentiation to NPCs. In keeping with this association with activating marks, we demonstrate a role for FOXK transcription factors in gene activation during NPC differentiation. FOXK2 occupancy in ESCs is therefore an early mark for delineating the regulatory regions, which become activated in later lineages.


Asunto(s)
Diferenciación Celular/genética , Células Madre Embrionarias/metabolismo , Factores de Transcripción Forkhead/metabolismo , Activación Transcripcional , Linaje de la Célula/genética , Células Cultivadas , Cromatina/metabolismo , Células Madre Embrionarias/citología , Endodermo/citología , Elementos de Facilitación Genéticos , Código de Histonas , Humanos , Mesodermo/citología , Células-Madre Neurales/metabolismo , Neurogénesis/genética , Factores de Transcripción/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...