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1.
Oncogene ; 42(21): 1716-1727, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37029299

RESUMEN

Recurrence remains a significant clinical barrier to improving breast cancer patient outcomes. The RON receptor is a predictor of metastatic progression and recurrence in breast cancers of all subtypes. RON directed therapies are in development, but preclinical data directly testing the impact of RON inhibition on metastatic progression/recurrence are lacking, and mechanisms to exert this function remain unclear. Herein, we modeled breast cancer recurrence using implantation of RON-overexpressing murine breast cancer cells. Recurrent growth was examined after tumor resection via in vivo imaging and ex vivo culture of circulating tumor cells from whole blood samples from tumor bearing mice. In vitro functional assessment of was performed using mammosphere formation assays. Transcriptomic pathway enrichment identified glycolysis and cholesterol biosynthesis pathways, transcription factor targets, and signaling pathways enriched in RON-overexpressing breast cancer cells. BMS777607, a RON inhibitor, abrogated CTC colony formation tumor cells and tumor recurrence. RON promoted mammosphere formation through upregulated cholesterol production that utilizes glycolysis-derived substrates. In mouse models with RON overexpression, statin-mediated inhibition of cholesterol biosynthesis impeded metastatic progression and recurrence but does not affect the primary tumor. RON upregulates glycolysis and cholesterol biosynthesis gene expression by two pathways: MAPK-dependent c-Myc expression and ß-catenin -dependent SREBP2 expression.


Asunto(s)
Recurrencia Local de Neoplasia , Proteínas Tirosina Quinasas Receptoras , Animales , Ratones , Línea Celular Tumoral , Modelos Animales de Enfermedad , Recurrencia Local de Neoplasia/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal
2.
Vet Ophthalmol ; 26(3): 256-261, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37030668

RESUMEN

OBJECTIVE: To describe the successful use of endoscopy to visualize and place a soft canine ureteral stent to relieve a chronic nasolacrimal duct (NLD) obstruction in a horse. ANIMAL STUDIED: A 7-year-old, Quarter horse gelding. PROCEDURE: Under general anesthesia, retrograde nasolacrimal endoscopy was performed using an 8.5 Fr Storz Flex XC ureteroscope through the nasal punctum (NP). An obstructive web of fibrous tissue was visualized approximately 20 cm proximal to the NP. A 0.035″/150 cm hydrophilic guidewire was passed normograde from the ventral lacrimal punctum and used to puncture the stenotic tissue. Then, a 5.0Fr/70 cm open-end ureteral catheter was threaded normograde over the guidewire and NLD patency was re-established. The catheter confirmed a NLD length of 30 cm and was then removed. A 5.0Fr/22-32 cm Universa© Soft Ureteral Stent was threaded normograde over the guidewire until the loops of the stent were exposed at each end. The guidewire was removed and the stent loops were sutured in place. RESULTS: The stent was withdrawn 1 month after the procedure. Telephone follow-up with the client reported significant improvement in the amount of ocular discharge and decreased sensitivity around the face and ears. CONCLUSION: Endoscopy is a safe and effective procedure allowing for definitive diagnosis of NLD obstruction and to assist in interventional procedures. Placement of a canine indwelling ureteral stent seems to be an effective alternative treatment option for equine NLD obstruction compared to conventional invasive surgical procedures.


Asunto(s)
Dacriocistorrinostomía , Enfermedades de los Perros , Enfermedades de los Caballos , Obstrucción del Conducto Lagrimal , Conducto Nasolagrimal , Animales , Caballos , Masculino , Perros , Obstrucción del Conducto Lagrimal/terapia , Obstrucción del Conducto Lagrimal/veterinaria , Obstrucción del Conducto Lagrimal/diagnóstico , Conducto Nasolagrimal/cirugía , Endoscopía/veterinaria , Endoscopía/métodos , Dacriocistorrinostomía/veterinaria , Dacriocistorrinostomía/métodos , Stents/veterinaria , Enfermedades de los Perros/cirugía , Enfermedades de los Caballos/cirugía
3.
Genes (Basel) ; 14(2)2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36833444

RESUMEN

RON is a receptor tyrosine kinase (RTK) of the MET receptor family that is canonically involved in mediating growth and inflammatory signaling. RON is expressed at low levels in a variety of tissues, but its overexpression and activation have been associated with malignancies in multiple tissue types and worse patient outcomes. RON and its ligand HGFL demonstrate cross-talk with other growth receptors and, consequentially, positions RON at the intersection of numerous tumorigenic signaling programs. For this reason, RON is an attractive therapeutic target in cancer research. A better understanding of homeostatic and oncogenic RON activity serves to enhance clinical insights in treating RON-expressing cancers.


Asunto(s)
Neoplasias , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas Receptoras , Humanos , Factor de Crecimiento de Hepatocito , Ligandos , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal
4.
Vet Ophthalmol ; 26(2): 176-179, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36152337

RESUMEN

An 8-year-old female pre-metamorphic axolotl (Ambystoma mexicanum) was examined for a suspected anterior lens luxation. Slit-lamp biomicroscopy revealed two lens-like structures in the anterior chamber of the right eye (OD), each with cataractous change. Ultrasound biomicroscopy and optical coherence tomography (OCT) were performed without sedation, and revealed small lenticular structures each with distinct nuclei and cortices. Although a distinct connection of the two lenticular structures could not be definitively ruled out, the structures appeared separate. Each of the lenticular structures was closely associated with its respective iris leaflet. This report demonstrates application of advanced imaging for diagnostic use in axolotl ophthalmology, showing that imaging of the lens can be performed without sedation, topical anesthetic, nor contact gel with high diagnostic quality. Although two distinct lenses were diagnosed with no historical evidence of trauma, the small sizes of each lenticular structure, with no detectable connection between them, are suggestive of a possible regenerative abnormality. This report opens discussion for the regenerative capabilities of the pre-metamorphic adult axolotl and possible implementations of their use in regenerative medicine research for the development of future therapies.


Asunto(s)
Cristalino , Lentes , Femenino , Animales , Ambystoma mexicanum , Microscopía Acústica/veterinaria , Tomografía de Coherencia Óptica/veterinaria
5.
Nat Comput Sci ; 3(5): 443-454, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-38177849

RESUMEN

We present an additive approach for the inverse design of kirigami-based mechanical metamaterials by focusing on the empty (negative) spaces instead of the solid tiles. By considering each negative space as a four-bar linkage, we identify a simple recursive relationship between adjacent linkages, yielding an efficient method for creating kirigami patterns. This allows us to solve the kirigami design problem using elementary linear algebra, with compatibility, reconfigurability and rigid-deployability encoded into an iterative procedure involving simple matrix multiplications. The resulting linear design strategy circumvents the solution of a non-convex global optimization problem and allows us to control the degrees of freedom in the deployment angle field, linkage offsets and boundary conditions. We demonstrate this by creating a large variety of rigid-deployable, compact, reconfigurable kirigami patterns. We then realize our kirigami designs physically using two simple but effective fabrication strategies with very different materials. Altogether, our additive approaches present routes for efficient mechanical metamaterial design and fabrication based on ori/kirigami art forms.

6.
Aging (Albany NY) ; 13(17): 20992-21008, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34493690

RESUMEN

Despite the well-established association of gene expression deregulation with low muscle mass (LMM), the associated biological mechanisms remain unclear. Transcriptomic studies are capable to identify key mediators in complex diseases. We aimed to identify relevant mediators and biological mechanisms associated with age-related LMM. LMM-associated genes were detected by logistic regression using microarray data of 20 elderly women with LMM and 20 age and race-matched controls extracted from our SPAH Study (GSE152073). We performed weighted gene co-expression analysis (WGCNA) that correlated the identified gene modules with laboratorial characteristics. Gene enrichment analysis was performed and an LMM predictive model was constructed using Support Vector Machine (SVM). Overall, 821 discriminating transcripts clusters were identified (|beta coefficient| >1; p-value <0.01). From this list, 45 predictors of LMM were detected by SVM and validated with 0.7 of accuracy. Our results revealed that the well-described association of inflammation, immunity and metabolic alterations is also relevant at transcriptomic level. WGCNA highlighted a correlation of genes modules involved in immunity pathways with vitamin D level (R = 0.63, p = 0.004) and the Agatston score (R = 0.51, p = 0.02). Our study generated a predicted regulatory network and revealed significant metabolic pathways related to aging processes, showing key mediators that warrant further investigation.


Asunto(s)
Envejecimiento , Redes Reguladoras de Genes , Sistema Inmunológico , Inflamación , Músculo Esquelético , Sarcopenia/metabolismo , Transcriptoma , Anciano , Anciano de 80 o más Años , Femenino , Perfilación de la Expresión Génica , Humanos , Inflamación/genética , Inflamación/metabolismo , Modelos Logísticos , Redes y Vías Metabólicas , Sarcopenia/genética , Máquina de Vectores de Soporte , Vitamina D/sangre
7.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001605

RESUMEN

Inspired by the allure of additive fabrication, we pose the problem of origami design from a different perspective: How can we grow a folded surface in three dimensions from a seed so that it is guaranteed to be isometric to the plane? We solve this problem in two steps: by first identifying the geometric conditions for the compatible completion of two separate folds into a single developable fourfold vertex, and then showing how this foundation allows us to grow a geometrically compatible front at the boundary of a given folded seed. This yields a complete marching, or additive, algorithm for the inverse design of the complete space of developable quad origami patterns that can be folded from flat sheets. We illustrate the flexibility of our approach by growing ordered, disordered, straight, and curved-folded origami and fitting surfaces of given curvature with folded approximants. Overall, our simple shift in perspective from a global search to a local rule has the potential to transform origami-based metastructure design.

8.
J Zoo Wildl Med ; 51(4): 789-798, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33480559

RESUMEN

Two- and three-toed sloths (Choloepus spp. and Bradypus spp.) have become popular animals in American culture and in American zoos, where they are frequently used as animal ambassadors. Despite the increased focus on sloth species, the prevalence of infectious diseases in sloth populations and the associated clinical consequences are relatively unknown. This study reviewed all published literature from 1809 to 2019 that examined infectious agents in both captive and wild populations of either two- or three-toed sloths. Online databases were electronically searched for relevant manuscripts using strings of inclusion and exclusion terms, resulting in an initial identification of 5,364 articles. After removing duplications and conducting two relevance screenings, 57 manuscripts were included in the full review. A total of 1,769 individual two-toed sloths and 879 individual three-toed sloths were accounted for in the included studies, with evidence of infection or exposure to infectious agents in 647 (36.6%) and 222 (25.3%) individual two- and three-toed sloths, respectively. Approximately 74% of documented infections were cryptic fungal, parasitic, and viral infections. The remaining 26% of infections represent those that were associated with clinical signs of disease. The infectious agents reported were bacterial (84), parasitic (20), viral (9), and fungal (4). Significant knowledge gaps remain regarding clinical and subclinical infectious disease prevalence and impact in both free-ranging and captive sloths.


Asunto(s)
Infecciones Bacterianas/veterinaria , Micosis/veterinaria , Enfermedades Parasitarias en Animales/parasitología , Perezosos , Virosis/veterinaria , Animales , Infecciones Bacterianas/microbiología , Micosis/microbiología , Virosis/virología
9.
Genomics ; 113(1 Pt 2): 503-513, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32971215

RESUMEN

The association between Coronary Artery Calcification (CAC) and osteoporosis has been reported but not fully understood. Therefore, using an original bioinformatic framework we analyzed transcriptomic profiles of 20 elderly women with high CAC score and 31 age- and sex-matching controls from São Paulo Ageing & Health study (SPAH). We integrated differentially expressed microRNA (miRNA) and long-noncoding RNA (lncRNA) interactions with coding genes associated with CAC, in the context of bone-metabolism genes mined from literature. Top non-coding regulators of bone metabolism in CAC included miRNA 497-5p/195 and 106a-5p, and lncRNA FAM197Y7. Top non-coding RNAs revealed significant interplay between genes regulating bone metabolism, vascularization-related processes, chromatin organization, prostaglandin and calcium co-signaling. Prostaglandin E2 receptor 3 (PTGER3), Fibroblasts Growth Factor Receptor 1 (FGFR1), and One Cut Homeobox 2 (ONECUT2) were identified as the most susceptible to regulation by the top non-coding RNAs. This study provides a flexible transcriptomic framework including non-coding regulation for biomarker-related studies.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Redes Reguladoras de Genes , Osteoporosis Posmenopáusica/genética , ARN Largo no Codificante/metabolismo , Transcriptoma , Calcificación Vascular/genética , Anciano , Huesos/metabolismo , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Osteoporosis Posmenopáusica/metabolismo , ARN Largo no Codificante/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Subtipo EP3 de Receptores de Prostaglandina E/genética , Subtipo EP3 de Receptores de Prostaglandina E/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Calcificación Vascular/complicaciones , Calcificación Vascular/metabolismo
10.
Mol Genet Genomic Med ; 8(9): e1391, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32602654

RESUMEN

BACKGROUND: Vertebral fractures (VFs) are the most common clinical manifestation of osteoporosis associated with high morbimortality. A personal/familiar history of fractures increases the risk of fractures. The purpose of this study is to identify possible molecular markers associated with osteoporotic VFs in elderly women from community. METHODS: Transcriptomic analysis using Affymetrix HTA2 microarray was performed using whole blood samples of 240 subjects from a population-based survey (Sao Paulo Ageing & Health [SPAH] study). Only elderly women with osteoporosis diagnosis by densitometry were analyzed, and divided in two groups: VF: women with osteoporosis and VFs versus no vertebral fracture (NVF): women with osteoporosis and NVFs. They were matched for age, chronic disease, medication use, and bone mineral density (BMD). The logistic regression model adjusted for age was applied for transcriptome data analysis. SYBR green-based quantitative polymerase chain reaction (qPCR) was used to validate the most significant expression changes obtained in the microarray experiment. RESULTS: Microarray analysis identified 142 differentially expressed genes (DEGs, p < .01), 57 upregulated and 85 downregulated, compared VF versus NVF groups. The DEG with the greatest expression difference was the Gamma2-Syntrophin (SNTG2) (ß = 31.88, p = .005). Validation by qPCR confirmed increased expression in VF group of Syntrophin (SNTG2, fold change = 2.79, p = .009), TRAF3 Interacting Protein2 (TRAF3IP2, fold change = 2.79, p = .020), and Integrin Subunit Alpha 6 (ITGA6, fold change = 2.86, p = .038). CONCLUSION: Our data identified and validated the association of SNTG2 (608715), TRAF3IP2 (607043), and ITGA6 (147556) with osteoporotic VF in elderly women, independently of BMD. These results suggest that these transcripts have potential clinical significance and may help to explain the molecular mechanisms and biological functions of vertebral fracture.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Integrina alfa6/genética , Proteínas de la Membrana/genética , Proteínas Musculares/genética , Fracturas Osteoporóticas/genética , Fracturas de la Columna Vertebral/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Anciano de 80 o más Años , Femenino , Humanos , Integrina alfa6/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Musculares/metabolismo , Fracturas Osteoporóticas/metabolismo , Fracturas de la Columna Vertebral/metabolismo , Transcriptoma , Regulación hacia Arriba
11.
Nat Mater ; 18(9): 999-1004, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31435070

RESUMEN

Kirigami tessellations, regular planar patterns formed by partially cutting flat, thin sheets, allow compact shapes to morph into open structures with rich geometries and unusual material properties. However, geometric and topological constraints make the design of such structures challenging. Here we pose and solve the inverse problem of determining the number, size and orientation of cuts that enables the deployment of a closed, compact regular kirigami tessellation to conform approximately to any prescribed target shape in two or three dimensions. We first identify the constraints on the lengths and angles of generalized kirigami tessellations that guarantee that their reconfigured face geometries can be contracted from a non-trivial deployed shape to a compact, non-overlapping planar cut pattern. We then encode these conditions into a flexible constrained optimization framework to obtain generalized kirigami patterns derived from various periodic tesselations of the plane that can be deployed into a wide variety of prescribed shapes. A simple mechanical analysis of the resulting structure allows us to determine and control the stability of the deployed state and control the deployment path. Finally, we fabricate physical models that deploy in two and three dimensions to validate this inverse design approach. Altogether, our approach, combining geometry, topology and optimization, highlights the potential for generalized kirigami tessellations as building blocks for shape-morphing mechanical metamaterials.

12.
R Soc Open Sci ; 5(8): 172281, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30224995

RESUMEN

The identification of relationships in complex networks is critical in a variety of scientific contexts. This includes the identification of globally central nodes and analysing the importance of pairwise relationships between nodes. In this paper, we consider the concept of topological proximity (or 'closeness') between nodes in a weighted network using the generalized Erdos numbers (GENs). This measure satisfies a number of desirable properties for networks with nodes that share a finite resource. These include: (i) real-valuedness, (ii) non-locality and (iii) asymmetry. We show that they can be used to define a personalized measure of the importance of nodes in a network with a natural interpretation that leads to new methods to measure centrality. We show that the square of the leading eigenvector of an importance matrix defined using the GENs is strongly correlated with well-known measures such as PageRank, and define a personalized measure of centrality that is also well correlated with other existing measures. The utility of this measure of topological proximity is demonstrated by showing the asymmetries in both the dynamics of random walks and the mean infection time in epidemic spreading are better predicted by the topological definition of closeness provided by the GENs than they are by other measures.

14.
Ethn Dis ; 27(3): 249-256, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28811736

RESUMEN

OBJECTIVE: To report baseline characteristics of junior-level faculty participants in the Summer Institute Programs to Increase Diversity (SIPID) and the Programs to Increase Diversity among individuals engaged in Health-Related Research (PRIDE), which aim to facilitate participants' career development as independent investigators in heart, lung, blood, and sleep research. DESIGN AND SETTING: Junior faculty from groups underrepresented in the biomedical-research workforce attended two, 2-3 week, annual summer research-education programs at one of six sites. Programs provided didactic and/or laboratory courses, workshops to develop research, writing and career-development skills, as well as a mentoring component, with regular contact maintained via phone, email and webinar conferences. Between summer institutes, trainees participated in a short mid-year meeting and an annual scientific meeting. Participants were surveyed during and after SIPID/PRIDE to evaluate program components. PARTICIPANTS: Junior faculty from underrepresented populations across the United States and Puerto Rico participated in one of three SIPID (2007-2010) or six PRIDE programs (2011-2014). RESULTS: Of 204 SIPID/PRIDE participants, 68% were female; 67% African American and 27% Hispanic/Latino; at enrollment, 75% were assistant professors and 15% instructors, with most (96%) on non-tenure track. Fifty-eight percent had research doctorates (PhD, ScD) and 42% had medical (MD, DO) degrees. Mentees' feedback about the program indicated skills development (eg, manuscript and grant writing), access to networking, and mentoring were the most beneficial elements of SIPID and PRIDE programs. Grant awards shifted from primarily mentored research mechanisms to primarily independent investigator awards after training. CONCLUSIONS: Mentees reported their career development benefited from SIPID and PRIDE participation.


Asunto(s)
Investigación Biomédica/organización & administración , Docentes Médicos , Tutoría/métodos , Mentores , National Heart, Lung, and Blood Institute (U.S.) , Desarrollo de Programa , Femenino , Humanos , Masculino , Estados Unidos
16.
Ethn Dis ; 26(3): 379-86, 2016 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-27440978

RESUMEN

Aspiring junior investigators from groups underrepresented in the biomedical sciences face various challenges as they pursue research independence. However, the biomedical research enterprise needs their participation to effectively address critical research issues such as health disparities and health inequities. In this article, we share a research education and mentoring initiative that seeks to address this challenge: Programs to Increase Diversity among Individuals Engaged in Health Related Research (PRIDE), funded by the National Heart, Lung, and Blood Institute (NHLBI). This longitudinal research-education and mentoring program occurs through summer institute programs located at US-based academic institutions. Recruited participants are exposed to didactic and lab-based research-skill enhancement experiences, with year-round mentoring over the course of two years. Mentor-mentee matching is based on shared research interests to promote congruence and to enhance skill acquisition. Program descriptions and sample narratives of participants' perceptions of PRIDE's impact on their career progress are showcased. Additionally, we highlight the overall program design and structure of four of seven funded summer institutes that focus on cardiovascular disease, related conditions, and health disparities. Mentees' testimonials about the value of the PRIDE mentoring approach in facilitating career development are also noted. Meeting the clinical and research needs of an increasingly diverse US population is an issue of national concern. The PRIDE initiative, which focuses on increasing research preparedness and professional development of groups underrepresented in the biomedical research workforce, with an emphasis on mentoring as the critical approach, provides a robust model that is impacting the careers of future investigators.


Asunto(s)
Diversidad Cultural , Mentores , National Heart, Lung, and Blood Institute (U.S.) , Investigadores , Investigación Biomédica , Selección de Profesión , Humanos , Desarrollo de Programa , Estados Unidos
17.
Nat Mater ; 15(5): 583-8, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26808459

RESUMEN

Origami describes rules for creating folded structures from patterns on a flat sheet, but does not prescribe how patterns can be designed to fit target shapes. Here, starting from the simplest periodic origami pattern that yields one-degree-of-freedom collapsible structures-we show that scale-independent elementary geometric constructions and constrained optimization algorithms can be used to determine spatially modulated patterns that yield approximations to given surfaces of constant or varying curvature. Paper models confirm the feasibility of our calculations. We also assess the difficulty of realizing these geometric structures by quantifying the energetic barrier that separates the metastable flat and folded states. Moreover, we characterize the trade-off between the accuracy to which the pattern conforms to the target surface, and the effort associated with creating finer folds. Our approach enables the tailoring of origami patterns to drape complex surfaces independent of absolute scale, as well as the quantification of the energetic and material cost of doing so.

18.
PLoS One ; 10(12): e0144660, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26713848

RESUMEN

High-level fetal (γ) globin expression ameliorates clinical severity of the beta (ß) hemoglobinopathies, and safe, orally-bioavailable γ-globin inducing agents would benefit many patients. We adapted a LCR-γ-globin promoter-GFP reporter assay to a high-throughput robotic system to evaluate five diverse chemical libraries for this activity. Multiple structurally- and functionally-diverse compounds were identified which activate the γ-globin gene promoter at nanomolar concentrations, including some therapeutics approved for other conditions. Three candidates with established safety profiles were further evaluated in erythroid progenitors, anemic baboons and transgenic mice, with significant induction of γ-globin expression observed in vivo. A lead candidate, Benserazide, emerged which demonstrated > 20-fold induction of γ-globin mRNA expression in anemic baboons and increased F-cell proportions by 3.5-fold in transgenic mice. Benserazide has been used chronically to inhibit amino acid decarboxylase to enhance plasma levels of L-dopa. These studies confirm the utility of high-throughput screening and identify previously unrecognized fetal globin inducing candidates which can be developed expediently for treatment of hemoglobinopathies.


Asunto(s)
Anemia/genética , Hemoglobina Fetal/genética , Ensayos Analíticos de Alto Rendimiento , Papio , Activación Transcripcional/efectos de los fármacos , gamma-Globinas/genética , Animales , Benserazida/efectos adversos , Benserazida/farmacología , Evaluación Preclínica de Medicamentos , Células Precursoras Eritroides/efectos de los fármacos , Loratadina/efectos adversos , Loratadina/análogos & derivados , Loratadina/farmacología , Ratones , Ratones Transgénicos , ARN Mensajero/genética , ARN Mensajero/metabolismo
19.
Exp Biol Med (Maywood) ; 240(8): 1050-64, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26283707

RESUMEN

The developmental regulation of globin gene expression has shaped research efforts to establish therapeutic modalities for individuals affected with sickle cell disease and ß-thalassemia. Fetal hemoglobin has been shown to block sickle hemoglobin S polymerization to improve symptoms of sickle cell disease; moreover, fetal hemoglobin functions to replace inadequate hemoglobin A synthesis in ß-thalassemia thus serving as an effective therapeutic target. In the perinatal period, fetal hemoglobin is synthesized at high levels followed by a decline to adult levels by one year of age. It is known that naturally occurring mutations in the γ-globin gene promoters and distant cis-acting transcription factors produce persistent fetal hemoglobin synthesis after birth to ameliorate clinical symptoms. Major repressor proteins that silence γ-globin during development have been targeted for gene therapy in ß-hemoglobinopathies patients. In parallel effort, several classes of pharmacological agents that induce fetal hemoglobin expression through molecular and cell signaling mechanisms have been identified. Herein, we reviewed the progress made in the discovery of signaling molecules targeted by pharmacologic agents that enhance γ-globin expression and have the potential for future drug development to treat the ß-hemoglobinopathies.


Asunto(s)
Envejecimiento , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/metabolismo , Hemoglobina Fetal/biosíntesis , Transducción de Señal/efectos de los fármacos , Humanos , Talasemia beta/tratamiento farmacológico , Talasemia beta/metabolismo
20.
Int J Pediatr Otorhinolaryngol ; 77(11): 1852-5, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24063769

RESUMEN

OBJECTIVE: Speech acquisition after cochlear implant is a long process. Various studies have followed the auditory milestones in the early period after implantation. The aim of the present study was to track the development of hearing skills in the early period after cochlear implantation and evaluate which factors influence the process. METHODS: 195 records of children implanted in the Hadassah Medical Center were examined retrospectively. Data on etiology, age at implantation and type of implant were collected. In addition, information on the rate of progress was measured: the first time that there was detection and identification of Ling sounds, the first time it was possible to obtain SDT (speech detection threshold), SRT (speech reception threshold) and an audiogram, and the first accurate repetition of VCV (vowel consonant vowel) sounds. RESULTS: Results show a consistent pattern of auditory milestone acquisition similar to that of normal development, from milestones that do not require decoding beginning with SDT, detection of Ling sounds followed by an audiogram which requires cooperation, to tasks that involve decoding starting with SRT and repetition of Ling sounds and finally VCV repetition. The children implanted before 24 months of age achieved the auditory milestones later than children implanted between 2 and 6 years, apparently since these tasks involve cognitive abilities which are not yet developed in the youngest children. Previous hearing experience improved the rate of acquisition of the auditory milestones and progress was faster in the second implanted ear compared to the first implanted ear. CONCLUSION: More research is needed to address the relationship between acquisition of early auditory milestones and performance with the cochlear implant later on in life.


Asunto(s)
Implantes Cocleares , Pérdida Auditiva Sensorineural/fisiopatología , Pérdida Auditiva Sensorineural/rehabilitación , Inteligibilidad del Habla , Percepción del Habla/fisiología , Factores de Edad , Análisis de Varianza , Audiometría de Tonos Puros/métodos , Umbral Auditivo , Niño , Preescolar , Implantación Coclear/métodos , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Pérdida Auditiva Sensorineural/diagnóstico , Humanos , Lactante , Masculino , Monitoreo Fisiológico/métodos , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
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