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1.
Nat Cell Biol ; 24(9): 1350-1363, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36075976

RESUMEN

Coordinated changes of cellular plasticity and identity are critical for pluripotent reprogramming and oncogenic transformation. However, the sequences of events that orchestrate these intermingled modifications have never been comparatively dissected. Here, we deconvolute the cellular trajectories of reprogramming (via Oct4/Sox2/Klf4/c-Myc) and transformation (via Ras/c-Myc) at the single-cell resolution and reveal how the two processes intersect before they bifurcate. This approach led us to identify the transcription factor Bcl11b as a broad-range regulator of cell fate changes, as well as a pertinent marker to capture early cellular intermediates that emerge simultaneously during reprogramming and transformation. Multiomics characterization of these intermediates unveiled a c-Myc/Atoh8/Sfrp1 regulatory axis that constrains reprogramming, transformation and transdifferentiation. Mechanistically, we found that Atoh8 restrains cellular plasticity, independent of cellular identity, by binding a specific enhancer network. This study provides insights into the partitioned control of cellular plasticity and identity for both regenerative and cancer biology.


Asunto(s)
Reprogramación Celular , Células Madre Pluripotentes Inducidas , Plasticidad de la Célula/genética , Reprogramación Celular/genética , Células Madre Pluripotentes Inducidas/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo
2.
Br J Radiol ; 87(1035): 20130392, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24588666

RESUMEN

The term vascular anomaly represents a broad spectrum of vascular pathology, including proliferating vascular tumours and vascular malformations. While the treatment of most vascular anomalies is multifactorial, interventional radiology procedures, including embolic therapy, sclerotherapy and laser coagulation among others, are playing an increasingly important role in vascular anomaly management. This review discusses the diagnosis and treatment of common vascular malformations, with emphasis on the technique, efficacy and complications of different interventional radiology procedures.


Asunto(s)
Radiografía Intervencional/métodos , Malformaciones Vasculares/clasificación , Malformaciones Vasculares/diagnóstico por imagen , Malformaciones Arteriovenosas/diagnóstico por imagen , Capilares/anomalías , Hemangioma/diagnóstico por imagen , Humanos , Sistema Linfático/anomalías , Mancha Vino de Oporto/diagnóstico por imagen , Neoplasias Vasculares/diagnóstico por imagen , Venas/anomalías
3.
Rev Sci Instrum ; 83(7): 073303, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22852681

RESUMEN

Neutron depth profiling (NDP) is a mature, nondestructive technique used to characterize the concentration of certain light isotopes in a material as a function of depth by measuring the residual energy of charged particles in neutron induced reactions. Historically, NDP has been performed using a single detector, resulting in low intrinsic detection efficiency, and limiting the technique largely to high flux research reactors. In this work, we describe a new NDP instrument design with higher detection efficiency by way of spectrum summing across multiple detectors. Such a design is capable of acquiring a statistically significant charged particle spectrum at facilities limited in neutron flux and operation time.

5.
J Hand Surg Br ; 25(3): 314-6, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10961564

RESUMEN

We report treatment of a low grade parosteal osteosarcoma of the ring finger metacarpal in a patient who would not contemplate ray amputation because of her career. Surgery involved excision of the bone, extracorporeal radiation then re-implantation.


Asunto(s)
Neoplasias Óseas/cirugía , Metacarpo , Música , Enfermedades Profesionales/cirugía , Osteosarcoma Yuxtacortical/cirugía , Neoplasias Óseas/diagnóstico por imagen , Femenino , Humanos , Metacarpo/cirugía , Persona de Mediana Edad , Osteosarcoma Yuxtacortical/diagnóstico por imagen , Reimplantación , Tomografía Computarizada por Rayos X
8.
N Engl J Med ; 336(17): 1197-201, 1997 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-9110906

RESUMEN

BACKGROUND: Neonatal circumcision is a painful surgical procedure often performed without analgesia. We assessed the efficacy and safety of 5 percent lidocaine-prilocaine cream (Emla) in neonates undergoing circumcision. METHODS: We carried out a double-blind, randomized, controlled trial in 68 full-term male neonates: 38 were assigned to receive lidocaine-prilocaine cream, and 30 to receive placebo. One gram of lidocaine-prilocaine or placebo cream was applied to the penis under an occlusive dressing for 60 to 80 minutes before circumcision. Behavioral (facial activity and time spent crying) and physiologic (heart rate and blood pressure) responses were recorded during the procedure. Blood samples were obtained at various times after drug application for measurements of methemoglobin and plasma lidocaine, prilocaine, and o-toluidine (a metabolite of prilocaine). RESULTS: A total of 68 and 59 neonates were included in the safety and efficacy analyses, respectively. Demographic characteristics such as gestational age and birth weight did not differ between the lidocaine-prilocaine and placebo groups. During circumcision, the neonates in the lidocaine-prilocaine group had less facial activity (P= 0.01), spent less time crying (P<0.001), and had smaller increases in heart rate (P=0.007) than the neonates in the placebo group. Facial-activity scores were 12 to 49 percent lower during various steps of the procedure in the lidocaine-prilocaine group. As compared with neonates in the placebo group, infants in the lidocaine-prilocaine group cried less than half as much and had heart-rate increases of 10 beats per minute less. Blood methemoglobin concentrations (expressed as a percentage of the hemoglobin concentration) were similar (1.3 percent) in both groups. Lidocaine and prilocaine were detected in plasma in 23 (61 percent) and 21 (55 percent) of the infants treated with lidocaine-prilocaine cream, respectively. CONCLUSIONS: Lidocaine-prilocaine cream is efficacious and safe for the prevention of pain from circumcision in neonates.


Asunto(s)
Anestesia Local , Anestésicos Locales/uso terapéutico , Circuncisión Masculina/efectos adversos , Lidocaína/uso terapéutico , Dolor/prevención & control , Prilocaína/uso terapéutico , Anestesia Local/efectos adversos , Anestésicos Locales/efectos adversos , Llanto , Método Doble Ciego , Combinación de Medicamentos , Frecuencia Cardíaca , Humanos , Recién Nacido , Lidocaína/efectos adversos , Masculino , Metahemoglobinemia , Pomadas , Dolor/etiología , Dolor/fisiopatología , Prilocaína/efectos adversos
10.
Dev Genet ; 18(4): 316-24, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8754283

RESUMEN

During oogenesis in Drosophila, germ cells appear in sequential clusters of 16 interconnected cells. The events surrounding the differentiation of these cells are not fully understood. Here we present genetic and morphological analysis of mutations in the gene stand still (stil). Through complementation analyses we have refined the location of this gene to cyological region 49B-C. Our analyses of ovaries from ethylmethane sulfonate (EMS)-induced mutant alleles of this gene suggest that mutations in the stil gene produce a wide range of phenotypic abnormalities, from the absence of germ cells in the most severe alleles, to egg chambers with cytoskeletal defects in the less severe alleles. Our results suggest a role for this gene in specifying or maintaining a cytoskeletal component, with consequences during oogenesis and possibly during germ line sex determination.


Asunto(s)
Drosophila/genética , Genes de Insecto , Oogénesis/genética , Ovario/citología , Óvulo/citología , Actinas/ultraestructura , Alelos , Animales , Diferenciación Celular/genética , Mapeo Cromosómico , Citoesqueleto/ultraestructura , Femenino , Mutación , Fenotipo
11.
J Hand Surg Br ; 20(5): 679-80, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8543880

RESUMEN

With the increasing popularity of day case surgery it is important to ensure that safe and appropriate techniques are being used. We retrospectively reviewed a large series of 732 patients who underwent planned day case hand surgery under intravenous regional anaesthesia (modified Bier's block) over a 5-year period. We found a modified Bier's block to be ideally suited to day case surgery with no deaths, minimal morbidity and a success rate in excess of 98%.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Mano/cirugía , Bloqueo Nervioso , Adulto , Anciano , Anestesia Local/métodos , Anestésicos Locales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Prilocaína
12.
J Hand Surg Br ; 15(4): 484-6, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2269844

RESUMEN

Haemangioma of bone is a rare benign tumour of blood vessels. We report a case arising in a middle phalanx and the problems encountered in its management.


Asunto(s)
Neoplasias Óseas/cirugía , Dedos/patología , Hemangioma/cirugía , Adulto , Neoplasias Óseas/patología , Femenino , Hemangioma/patología , Humanos
13.
Mol Cell Biol ; 8(4): 1481-8, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3132610

RESUMEN

The female-sterile ovarian tumor gene, otu, is located in cytological region 7F1 on the Drosophila melanogaster chromosome map. We have mapped the gene at the molecular level by using four dysgenic alleles and two revertant derivatives of these alleles as well as an ethyl methanesulfonate-induced allele. The insertional (dysgenic) changes were all associated with one restriction fragment, and its size was restored after phenotypic reversion. One ethyl methanesulfonate-induced allele had a deletion in the restriction fragment adjacent (distal) to the fragment altered in the insertional alleles. These two restriction fragments were immediately adjacent to the s38 chorion gene. Associated with the two altered restriction fragments were two RNA species, an abundant 3.2-kilobase (kb) poly(A)+ RNA and a minor 4.0-kb RNA. Several other less-abundant RNA species were detectable with more-sensitive single-stranded RNA probes. The otu gene was transcribed proximal to distal relative to the centromere; this was opposite to the direction of transcription of the adjacent s38 gene. During development, the 3.2-kb RNA was absent in larvae, first appeared in the pupal stages, and persisted in adult females, in which it was most prevalent in the ovaries. The DNA that hybridized to the 3.2-kb ovarian RNA hybridized to four different RNAs found in the testes but not in the rest of the adult male. These testis-enriched RNAs were transcribed from the same strand of DNA as the ovarian transcripts.


Asunto(s)
Drosophila melanogaster/genética , Genes , Transcripción Genética , Alelos , Animales , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Heterocigoto , Infertilidad Femenina , Mutación , Hibridación de Ácido Nucleico , Neoplasias Ováricas , Polimorfismo Genético
14.
Injury ; 17(3): 201-2, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3818061

RESUMEN

Breakdancing is an acrobatic dance that involves spinning on various parts of the body including the head, dorsal spine and hand. Three cases are reported of partial rupture of the ulnar collateral ligament (UCL) of the thumb, associated with a fracture of the base of the proximal phalanx which occurred as a result of torsional forces applied to the abducted and hyperextended thumb. It appears to be a distinct clinical entity. In all cases, open reduction was required and led to excellent functional recovery.


Asunto(s)
Baile , Fracturas Cerradas/etiología , Ligamentos Articulares/lesiones , Pulgar/lesiones , Adolescente , Humanos
15.
Gene ; 34(2-3): 155-61, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2989106

RESUMEN

A mouse genomic library in lambda Charon 4A was screened for putative ribosomal protein genes using a fragment of the gene encoding Drosophila ribosomal protein 49 as a hybridization probe under nonstringent hybridization conditions. A recombinant phage was selected and its restriction enzyme map determined. The major species of mouse poly(A)+ mRNA homologous to the putative gene is about 740 nucleotides long.


Asunto(s)
Drosophila melanogaster/genética , Proteínas Ribosómicas/genética , Animales , Evolución Biológica , Mapeo Cromosómico , Enzimas de Restricción del ADN , Genes , Ratones , Hibridación de Ácido Nucleico , Poli A/genética , ARN Mensajero/genética
16.
Histochemistry ; 82(3): 233-47, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2581922

RESUMEN

DNA replication patterns in the nurse and follicle cells of wild type and a female sterile mutant, fs(1)1304, of Drosophila melanogaster have been studied by DNA-Feulgen cytophotometry, using a cell dispersal technique that allowed the measurement of DNA amounts in individual nuclei from egg chambers of known developmental stages. DNA-Feulgen values associated with various ovarian nuclei from egg chambers at different stages of development were used to assess a base line DNA content for ovarian tissues and to estimate the extent of DNA replication in the nurse cells and follicle cells of growing and mature egg chambers. Our data show that both the nurse and follicle cells undergo multiple cycles of endonuclear DNA replication and that there may be selective amplification as well as underreplication by portions of the genome in these highly polyploid, ovarian cells. Alternative models are proposed to account for the DNA replication patterns observed. Comparisons of DNA-Feulgen levels in wild type ovarian nuclei with those found for the fs(1)1304 mutant and its heterozygote in the balanced stock fs/FM3, show that equivalent DNA levels are present in follicle cell nuclei from all three types of females. Nurse cell nuclei in the homozygous fs stock, however, fail to achieve the same high DNA levels observed in both fs/FM3 and wild type nurse cell nuclei. Although the nuclei of follicle cells in ovaries from fs/fs females appear morphologically like those surrounding egg chambers in wild type ovaries, nurse cell nuclei from mutant females show a more compacted organization of their chromatin than found for nurse cell nuclei from wild type ovaries at similar developmental stages. Our findings suggest that a major effect of the fs(1)1304 mutation may be on the coiling behavior of chromatin and the conformation of DNA-protein moieties in both nurse cell and follicle cell nuclei. These changes in chromatin structure apparently are manifest by perturbations in DNA replication patterns and normal gene function in these biosynthetically active cells.


Asunto(s)
Colorantes , ADN/análisis , Drosophila melanogaster/análisis , Colorantes de Rosanilina , Animales , Núcleo Celular/análisis , Drosophila melanogaster/genética , Femenino , Gónadas/análisis , Mutación , Coloración y Etiquetado
19.
J Exp Zool ; 217(1): 109-18, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6167658

RESUMEN

The female sterile mutant of Drosophila melanogaster, fs(1)1304 (1-19 +/- 2), has been characterized. Our studies show that the mutation affects the organization of nucleolar material in the ovarian nurse cells and the pattern of RNA metabolism in the ovary. Autoradiographic analysis of incorporation of 3H-uridine in vivo and analysis of 3H-uridine incorporation into high molecular weight RNA in vitro suggest that RNA from the ovaries of homozygous fs flies is degraded at a higher rate than that from heterozygous fs and wild-type ovaries. It is likely that the RNA class affected is ribosomal RNA. These data are discussed in the context of the functional role for the wild-type gene allelic to fs(1)1304, and it is suggested that one of the effects of the mutation may be on the biogenesis of ribosomes that are to be stored in the oocyte.


Asunto(s)
Drosophila melanogaster/metabolismo , ARN/metabolismo , Animales , Drosophila melanogaster/genética , Femenino , Genes , Cinética , Mutación , Ovario/metabolismo , ARN/análisis , Reproducción
20.
Hand ; 12(1): 44-50, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7364327

RESUMEN

A technique is described for treating severe compound injuries of the phalanges either single or multiple, with transverse Kirschner wires bonded with acrylic cement. The operative procedure, post-operative management and advantages of the technique are described.


Asunto(s)
Amputación Traumática/cirugía , Traumatismos de los Dedos/cirugía , Fijación de Fractura/métodos , Adulto , Fijación de Fractura/instrumentación , Humanos , Masculino , Persona de Mediana Edad
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