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BACKGROUND: While many developmentally relevant enhancers act in a modular fashion, there is growing evidence for nonadditive interactions between distinct cis-regulatory enhancers. We investigated if nonautonomous enhancer interactions underlie transcription regulation of the Drosophila segment polarity gene, wingless. RESULTS: We identified two wg enhancers active at the blastoderm stage: wg 3613u, located from -3.6 to -1.3 kb upstream of the wg transcription start site (TSS) and 3046d, located in intron two of the wg gene, from 3.0 to 4.6 kb downstream of the TSS. Genetic experiments confirm that Even Skipped (Eve), Fushi-tarazu (Ftz), Runt, Odd-paired (Opa), Odd-skipped (Odd), and Paired (Prd) contribute to spatially regulated wg expression. Interestingly, there are enhancer specific differences in response to the gain or loss of function of pair-rule gene activity. Although each element recapitulates aspects of wg expression, a composite reporter containing both enhancers more faithfully recapitulates wg regulation than would be predicted from the sum of their individual responses. CONCLUSION: These results suggest that the regulation of wg by pair-rule genes involves nonadditive interactions between distinct cis-regulatory enhancers.
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Proteínas de Drosophila/metabolismo , Drosophila/embriología , Drosophila/metabolismo , Animales , Blastodermo/embriología , Blastodermo/metabolismo , Tipificación del Cuerpo/genética , Tipificación del Cuerpo/fisiología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Drosophila/genética , Proteínas de Drosophila/genética , Factores de Transcripción Fushi Tarazu/genética , Factores de Transcripción Fushi Tarazu/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína Wnt1/genética , Proteína Wnt1/metabolismoRESUMEN
This paper describes the supramolecular assembly of a macrocyclic ß-sheet containing residues 16-22 of the ß-amyloid peptide, Aß. X-ray crystallography reveals that the macrocyclic ß-sheet assembles to form double-walled nanotubes, with an inner diameter of 7 nm and outer diameter of 11 nm. The inner wall is composed of an extended network of hydrogen-bonded dimers. The outer wall is composed of a separate extended network of ß-barrel-like tetramers. These large peptide nanotubes pack into a hexagonal lattice that resembles a honeycomb. The complexity and size of the peptide nanotubes rivals some of the largest tubular biomolecular assemblies, such as GroEL and microtubules. These observations demonstrate that small amyloidogenic sequences can be used to build large nanostructures.
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Péptidos beta-Amiloides/química , Compuestos Macrocíclicos/química , Nanotubos/química , Fragmentos de Péptidos/química , Péptidos/síntesis química , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Estructura Molecular , Péptidos/químicaRESUMEN
A macrocyclic ß-sheet peptide containing two nonapeptide segments based on Aß(15-23) (QKLVFFAED) forms fibril-like assemblies of oligomers in the solid state. The X-ray crystallographic structure of macrocyclic ß-sheet peptide 3 was determined at 1.75 Å resolution. The macrocycle forms hydrogen-bonded dimers, which further assemble along the fibril axis in a fashion resembling a herringbone pattern. The extended ß-sheet comprising the dimers is laminated against a second layer of dimers through hydrophobic interactions to form a fibril-like assembly that runs the length of the crystal lattice. The second layer is offset by one monomer subunit, so that the fibril-like assembly is composed of partially overlapping dimers, rather than discrete tetramers. In aqueous solution, macrocyclic ß-sheet 3 and homologues 4 and 5 form discrete tetramers, rather than extended fibril-like assemblies. The fibril-like assemblies of oligomers formed in the solid state by macrocyclic ß-sheet 3 represent a new mode of supramolecular assembly not previously observed for the amyloidogenic central region of Aß. The structures observed at atomic resolution for this peptide model system may offer insights into the structures of oligomers and oligomer assemblies formed by full-length Aß and may provide a window into the propagation and replication of amyloid oligomers.
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Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/síntesis química , Cristalografía por Rayos X , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/química , Modelos Moleculares , Conformación ProteicaRESUMEN
Purpose: To present a case of keratoconus progression following gender-affirming hormone therapy. Observations: A 28-year-old male-to-female transgender patient with potential past ocular history of subclinical keratoconus presented with subacute worsening myopia of both eyes (OU), 4 months after initiation of gender-affirming hormone therapy. A diagnosis of keratoconus was established based on slit-lamp exam and computerized corneal tomography. Notable indices were central corneal thinning and inferior steepening OU with maximum corneal curvatures of 58.3 D of the right eye (OD) and 77.7 D of the left eye (OS) and thinnest corneal thickness of 440 µm OD and 397 µm OS. After 8 months of continued hormone therapy, the patient's keratoconus continued to progress and thus corneal crosslinking was recommended and performed. Conclusions: Keratoconus progression and relapse has been suggested to have an association with sex hormone changes. We report a case of keratoconus progression following gender-affirming hormone therapy in a transgender patient. Our findings continue to support a correlative relationship between sex hormones and corneal ectasia pathophysiology. Further studies are needed to determine causality and to investigate the utility of screening corneal structure prior to the initiation of gender-affirming hormone therapies.
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AIMS: Glucokinase (GK) is expressed in the glucose-sensing cells of the islets of Langerhans and plays a critical role in glucose homeostasis. Here, we tested the hypothesis that genetic activation of GK in a small subset of ß-cells is sufficient to change the glucose set-point of the whole islet. MATERIAL AND METHODS: Mouse models of cell-type specific GK deficiency (GKKO) and genetic enzyme activation (GKKI) in a subset of ß-cells were obtained by crossing the αGSU (gonadotropin alpha subunit)-Cre transgene with the appropriate GK mutant alleles. Metabolic analyses consisted of glucose tolerance tests, perifusion of isolated islets and intracellular calcium measurements. KEY FINDINGS: The αGSU-Cre transgene produced genetically mosaic islets, as Cre was active in 15 ± 1.2 % of ß-cells. While mice deficient for GK in a subset of islet cells were normal, unexpectedly, GKKI mice were chronically hypoglycemic, glucose intolerant, and had a lower threshold for glucose stimulated insulin secretion. GKKI mice exhibited an average fasting blood glucose level of 3.5 mM. GKKI islets responded with intracellular calcium signals that spread through the whole islets at 1 mM and secreted insulin at 3 mM glucose. SIGNIFICANCE: Genetic activation of GK in a minority of ß-cells is sufficient to change the glucose threshold for insulin secretion in the entire islet and thereby glucose homeostasis in the whole animal. These data support the model in which ß-cells with higher GK activity function as 'hub' or 'trigger' cells and thus control insulin secretion by the ß-cell collective within the islet.
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Hipoglucemia , Células Secretoras de Insulina , Islotes Pancreáticos , Ratones , Animales , Glucoquinasa/genética , Glucoquinasa/metabolismo , Células Secretoras de Insulina/metabolismo , Glucemia/metabolismo , Calcio/metabolismo , Islotes Pancreáticos/metabolismo , Insulina/metabolismo , Glucosa/metabolismo , Hipoglucemia/metabolismo , Hipoglucemiantes/metabolismoRESUMEN
T-cell malignancies often result in poor prognosis and outcome for patients. Immunotherapy has recently emerged as a revolutionary treatment against cancer, and the success seen in CD19 CAR clinical trials may extend to T cell diseases. However, a shared antigen pool coupled with the impact of T-cell depletion incurred by targeting T cell disease remain concepts to be clinically explored with caution. Here we report on the ability of T cells transduced with a CD5CAR to specifically and potently lyse malignant T-cell lines and primary tumors in vitro in addition to significantly improving in vivo control and survival of xenograft models of T-ALL. To extensively explore and investigate the biological properties of a CD5 CAR, we evaluated multiple CD5 CAR constructs and constructed 3 murine models to characterize the properties of CD5 down-regulation, the efficacy and specificity produced by different CD5 CAR construct designs, and the impact of incorporating a CD52 safety switch using CAMPATH to modulate the persistency and function of CAR cells. These data support the potential use of CD5CAR T cells in the treatment of T cell malignancies or refractory disease in clinical settings.
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Antígenos CD5/metabolismo , Inmunoterapia Adoptiva , Leucemia-Linfoma Linfoblástico de Células T Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Alemtuzumab/farmacología , Alemtuzumab/uso terapéutico , Animales , Línea Celular , Regulación hacia Abajo/efectos de los fármacos , Humanos , Masculino , Ratones , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Proteínas Recombinantes/metabolismo , Linfocitos T/inmunología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The recent FDA approval of the first CAR immunotherapy marks a watershed moment in the advancement toward a cure for cancer. CD19 CAR treatment for B cell acute lymphocytic leukemia has achieved unprecedented remission rates. However, despite success in treating previously relapsed and refractory patients, CD19 CAR faces similar challenges as traditional chemotherapy, in that malignancy can adapt and overcome treatment. The emergence of both antigen positive and negative blasts after CAR treatment represents a need to bolster current CAR approaches. Here, we report on the anti-tumor activity of a CAR T cell possessing 2 discrete scFv domains against the leukemic antigens CD19 and CD123. We determined that the resulting compound CAR (cCAR) T cell possesses consistent, potent, and directed cytotoxicity against each target antigen population both in vitro and in vivo. Our findings indicate that targeting CD19 and CD123 on B-ALL cells may be an effective strategy for augmenting the response against leukemic blasts and reducing rates of relapse.
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Antígenos CD19/inmunología , Inmunoterapia Adoptiva , Subunidad alfa del Receptor de Interleucina-3/inmunología , Leucemia de Células B/inmunología , Leucemia de Células B/terapia , Alemtuzumab/farmacología , Alemtuzumab/uso terapéutico , Animales , Epítopos/inmunología , Humanos , Células K562 , Leucemia de Células B/tratamiento farmacológico , Leucemia de Células B/patología , Linfoma de Células B/inmunología , Linfoma de Células B/terapia , Masculino , RatonesRESUMEN
PURPOSE: To report the first successful implantation of a CyPass supraciliary stent combined with 2 targeted iStent trabecular microbypass stents in a phakic primary open-angle glaucoma patient with markedly elevated intraocular pressures (IOP) on maximum tolerable medical therapy. METHODS: Case report. RESULTS: A 52-year-old phakic male patient with primary open-angle glaucoma with uncontrolled IOP in the right eye (OD) of 36 mm Hg on maximal topical pharmacotherapy. The patient underwent implantation of a single CyPass supraciliary stent combined with the targeted implantation of 2 iStent trabecular microbypass stents, 1 right facing stent and 1 left facing stent. Postoperatively, off of all glaucoma medications, the IOP decreased to 10 mm Hg on day 1 and continued to be controlled between 10 to 13 mm Hg until postoperative month 6, with only 1 glaucoma medication added after postoperative month 5. In addition, there were no postoperative complications to date. CONCLUSIONS: The combined implantation of a CyPass supraciliary stent and iStent trabecular microbypass stents can successfully lower IOP and decrease medication burden with minimal risk for complications.
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Cuerpo Ciliar/cirugía , Glaucoma de Ángulo Abierto/cirugía , Cristalino/fisiología , Implantación de Prótesis , Stents , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Periodo PosoperatorioRESUMEN
Internet gaming is a legitimate leisure activity worldwide; however, there are emerging concerns that vast numbers of gamers are becoming addicted. In 2013, the American Psychiatric Association (APA) classified Internet Gaming Disorder (IGD) as a condition warranting more clinical research ahead of formalizing it as a mental disorder. Proposed as a behavioral addiction, IGD shares many similarities in both physical and psychosocial manifestations with substance use disorder, including cerebral changes on functional magnetic resonance imaging (fMRI). Among the gaming population, compared to females, adolescent and adult males demonstrate far more addictive internet gaming use in terms of screen hours, craving, and negative impacts on health, which have, in isolated incidents, also caused death. The current article draws findings from a scoping review of literature related to IGD as a means to raising awareness about an emergent men's health issue. Included are three themes: (a) unveiling the nature, impacts and symptoms of IGD; (b) conceptualizing IGD through neuroscience; and (c) treatment approaches to IGD. Afforded by these themes is an overview and synthesis of the existing literature regarding IGD as a means of providing direction for much needed research on gaming addiction and orientating primary care providers (PCPs) to the specificities of IGD in men's health. The findings are applied to a discussion of the connections between IGD and masculinity and the importance of recognizing how behaviors such as social isolation and game immersion can be maladaptive coping strategies for males.
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Conducta Adictiva/epidemiología , Conducta Adictiva/psicología , Salud del Hombre , Juegos de Video/psicología , Juegos de Video/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Humanos , Incidencia , Internet/estadística & datos numéricos , Masculino , Salud Mental , Medición de Riesgo , Estados UnidosRESUMEN
Acute myeloid leukemia (AML) bears heterogeneous cells that can consequently offset killing by single-CAR-based therapy, which results in disease relapse. Leukemic stem cells (LSCs) associated with CD123 expression comprise a rare population that also plays an important role in disease progression and relapse. Here, we report on the robust anti-tumor activity of a compound CAR (cCAR) T-cell possessing discrete scFv domains targeting two different AML antigens, CD123, and CD33, simultaneously. We determined that the resulting cCAR T-cells possessed consistent, potent, and directed cytotoxicity against each target antigen population. Using four leukemia mouse models, we found superior in vivo survival after cCAR treatment. We also designed an alemtuzumab safety-switch that allowed for rapid cCAR therapy termination in vivo. These findings indicate that targeting both CD123 and CD33 on AML cells may be an effective strategy for eliminating both AML bulk disease and LSCs, and potentially prevent relapse due to antigen escape or LSC persistence.
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Inmunoterapia Adoptiva/métodos , Subunidad alfa del Receptor de Interleucina-3/antagonistas & inhibidores , Leucemia Mieloide Aguda/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Lectina 3 Similar a Ig de Unión al Ácido Siálico/antagonistas & inhibidores , Alemtuzumab/uso terapéutico , Animales , Línea Celular Tumoral , Citotoxicidad Inmunológica , Humanos , Masculino , RatonesRESUMEN
Peripheral T-cell lymphomas (PTCLs) are a group of very aggressive non-Hodgkin's lymphomas (NHLs) with poor prognoses and account for a majority of T-cell malignancies. Overall, the standard of care for patients with T-cell malignancies is poorly established, and there is an urgent clinical need for a new approach. As demonstrated in B-cell malignancies, chimeric antigen receptor (CAR) immunotherapy provides great hope as a curative treatment regimen. Because PTCLs develop from mature T-cells, these NHLs are commonly CD4+, and CD4 is highly and uniformly expressed. Therefore, CD4 is an ideal target for PTCL CAR immunotherapy. To that effect, we created a robust third-generation anti-CD4 CAR construct (CD4CAR) and introduced it into clonal NK cells (NK-92). CD4CAR NK-92 cells specifically and robustly eliminated diverse CD4+ human T-cell leukemia and lymphoma cell lines (KARPAS-299, CCRF-CEM, and HL60) and patient samples ex vivo. Furthermore, CD4CAR NK-92 cells effectively targeted KARPAS-299 cells in vivo that modeled difficult-to-access lymphoma nodules, significantly prolonging survival. In our study, we present novel targeting of CD4 using CAR-modified NK cells, and demonstrate efficacy. Combined, our data support CD4CAR NK cell immunotherapy as a potential new avenue for the treatment of PTCLs and CD4+ T-cell malignancies.
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This paper elucidates the teixobactin pharmacophore by comparing the arginine analogue of teixobactin Arg10-teixobactin to seven homologues with varying structure and stereochemistry. The roles of the guanidinium group at position 10, the stereochemistry of the macrolactone ring, and the "tail" comprising residues 1-5 are investigated. The guanidinium group is not necessary for activity; Lys10-teixobactin is more active than Arg10-teixobactin against Gram-positive bacteria in minimum inhibitory concentration (MIC) assays. The relative stereochemistry of the macrolactone ring is important. Diastereomer l-Thr8,Arg10-teixobactin is inactive, and diastereomer d-allo-Ile11,Arg10-teixobactin is less active. The macrolactone ring is critical; seco-Arg10-teixobactin is inactive. The absolute stereochemistry is not important; the enantiomer ent-Arg10-teixobactin is comparable in activity. The hydrophobic N-terminal tail is important. Truncation of residues 1-5 results in loss of activity, and replacement of residues 1-5 with a dodecanoyl group partially restores activity. These findings pave the way for developing simpler homologues of teixobactin with enhanced pharmacological properties.
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Antibacterianos/química , Depsipéptidos/química , Antibacterianos/farmacología , Depsipéptidos/farmacología , Bacterias Grampositivas/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , EstereoisomerismoAsunto(s)
Extracción de Catarata , Facoemulsificación , Trabeculectomía , Cuerpo Ciliar/cirugía , HumanosRESUMEN
Peripheral T-cell lymphomas (PTCLS) comprise a diverse group of difficult to treat, very aggressive non-Hodgkin's lymphomas (NHLS) with poor prognoses and dismal patient outlook. Despite the fact that PTCLs comprise the majority of T-cell malignancies, the standard of care is poorly established. Chimeric antigen receptor (CAR) immunotherapy has shown in B-cell malignancies to be an effective curative option and this extends promise into treating T-cell malignancies. Because PTCLS frequently develop from mature T-cells, CD3 is similarly strongly and uniformly expressed in many PTCL malignancies, with expression specific to the hematological compartment thus making it an attractive target for CAR design. We engineered a robust 3rd generation anti-CD3 CAR construct (CD3CAR) into an NK cell line (NK-92). We found that CD3CAR NK-92 cells specifically and potently lysed diverse CD3+ human PTCL primary samples as well as T-cell leukemia cells lines ex vivo. Furthermore, CD3CAR NK-92 cells effectively controlled and suppressed Jurkat tumor cell growth in vivo and significantly prolonged survival. In this study, we present the CAR directed targeting of a novel target - CD3 using CAR modified NK-92 cells with an emphasis on efficacy, specificity, and potential for new therapeutic approaches that could improve the current standard of care for PTCLs.
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Complejo CD3/inmunología , Inmunoterapia Adoptiva/métodos , Células Asesinas Naturales/inmunología , Linfoma de Células T Periférico/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Animales , Complejo CD3/metabolismo , Técnicas de Cocultivo , Humanos , Células Jurkat , Estimación de Kaplan-Meier , Células Asesinas Naturales/trasplante , Linfoma de Células T Periférico/inmunología , Linfoma de Células T Periférico/mortalidad , Masculino , Ratones , Ratones SCID , Receptores de Antígenos de Linfocitos T/uso terapéutico , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/uso terapéutico , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
OBJECTIVE: Somatosensation is critical for effective object manipulation, but current upper limb prostheses do not provide such feedback to the user. For individuals who require use of prosthetic limbs, this lack of feedback transforms a mundane task into one that requires extreme concentration and effort. Although vibrotactile motors and sensory substitution devices can be used to convey gross sensations, a direct neural interface is required to provide detailed and intuitive sensory feedback. The viability of intracortical microstimulation (ICMS) as a method to deliver feedback depends in part on the long-term reliability of implanted electrodes used to deliver the stimulation. The objective of the present study is to investigate the effects of chronic ICMS on the electrode-tissue interface. APPROACH: We stimulate the primary somatosensory cortex of three Rhesus macaques through chronically implanted electrodes for 4 h per day over a period of six months, with different electrodes subjected to different regimes of stimulation. We measure the impedance and voltage excursion as a function of time and of ICMS parameters. We also test the sensorimotor consequences of chronic ICMS by having animals grasp and manipulate small treats. MAIN RESULTS: We show that impedance and voltage excursion both decay with time but stabilize after 10-12 weeks. The magnitude of this decay is dependent on the amplitude of the ICMS and, to a lesser degree, the duration of individual pulse trains. Furthermore, chronic ICMS does not produce any deficits in fine motor control. SIGNIFICANCE: The results suggest that chronic ICMS has only a minor effect on the electrode-tissue interface and may thus be a viable means to convey sensory feedback in neuroprosthetics.
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Electrodos Implantados , Fuerza de la Mano/fisiología , Corteza Somatosensorial/fisiología , Animales , Estimulación Eléctrica/métodos , Femenino , Macaca mulatta , Masculino , Microelectrodos , Factores de TiempoRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory loss and behavioral and psychological symptoms of dementia. An imbalance of different neurotransmitters--glutamate, acetylcholine, dopamine, and serotonin--has been proposed as the neurobiological basis of behavioral symptoms in AD. The molecular changes associated with neurotransmission imbalance in AD are not clear. We hypothesized that altered reuptake of neurotransmitters by vesicular glutamate transporters (VGLUTs), excitatory amino acid transporters (EAATs), the vesicular acetylcholine transporter (VAChT), the serotonin reuptake transporter (SERT), or the dopamine reuptake transporter (DAT) are involved in the neurotransmission imbalance in AD. We tested this hypothesis by examining protein and mRNA levels of these transporters in postmortem prefrontal cortex from 10 AD patients and 10 matched non-AD controls. Compared with controls, protein and mRNA levels of VGLUTs, EAAT1-3, VAChT, and SERT were reduced significantly in AD. Expression of DAT and catechol O-methyltransferase was unchanged. Reduced VGLUTs and EAATs may contribute to an alteration in glutamatergic recycling, and reduced SERT could exacerbate depressive symptoms in AD. The reduced VAChT expression could contribute to the recognized cholinergic deficit in AD. Altered neurotransmitter transporters could contribute to the pathophysiology of AD and are potential targets for therapy.