RESUMEN
OBJECTIVE: Brief interventions could reduce adolescents' risk of depression and alcohol-related harms, but evidence of their feasibility and acceptability for low-and middle-income countries is lacking. To address this gap, we conducted a feasibility trial of the ASPIRE intervention, a four-session multi-component counselling intervention for South African adolescents. METHOD: We recruited 117 adolescents who met our inclusion criteria. Participants were randomly assigned to the ASPIRE intervention or a comparison condition. Outcomes were assessed at baseline, six-week, and three-month post-randomization time points. Primary outcomes were based on feasibility of study procedures and intervention delivery (assessed on seven predetermined progression criteria). Clinical outcomes (risk of depression and alcohol harms) were secondary. RESULTS: Despite modifications to all study procedures arising from Covid-19 restrictions, five of the seven key progression criteria were fully met, including: feasibility of data collection and outcome measures, counsellor competencies, randomization and blinding, adverse advents, and acceptability of the intervention. The progression criterion for recruitment and intervention retention were not fully met. CONCLUSION: Findings suggest that the ASPIRE intervention was generally feasible to deliver and acceptable to adolescents. However, modifications to the trial design and intervention delivery are needed to optimize the validity of a definitive randomized controlled trial of the ASPIRE intervention.
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Intervención en la Crisis (Psiquiatría) , Depresión , Humanos , Adolescente , Depresión/terapia , Estudios de Factibilidad , Sudáfrica , ConsejoRESUMEN
BACKGROUND: Effective brief treatments for methamphetamine use disorders (MAUD) are urgently needed to complement longer more intensive treatments in low and middle income countries, including South Africa. To address this gap, the purpose of this randomised feasibility trial was to determine the feasibility of delivering a six-session blended imaginal desensitisation, plus motivational interviewing (IDMI) intervention for adults with a MAUD. METHODS: We enrolled 60 adults with a MAUD and randomly assigned them 1:1 to the IDMI intervention delivered by clinical psychologists and a control group who we referred to usual care. Feasibility measures, such as rates of recruitment, consent to participate in the trial and retention, were calculated. Follow-up interviews were conducted at 6 weeks and 3 months post-enrollment. RESULTS: Over 9 months, 278 potential particiants initiated contact. Following initial screening 78 (28%) met inclusion criteria, and 60 (77%) were randomised. Thirteen of the 30 participants assigned to the treatment group completed the intervention. Both psychologists were highly adherent to the intervention, obtaining a fidelity rating of 91%. In total, 39 (65%) participants completed the 6-week follow-up and 40 (67%) completed the 3-month follow-up. The intervention shows potential effectiveness in the intention-to-treat analysis where frequency of methamphetamine use was significantly lower in the treatment than in the control group at both the 6 week and 3-month endpoints. No adverse outcomes were reported. CONCLUSIONS: This feasibility trial suggests that the locally adapted IDMI intervention is an acceptable and safe intervention as a brief treatment for MAUD in South Africa. Modifications to the study design should be considered in a fully powered, definitive controlled trial to assess this potentially effective intervention. Trial registration The trial is registered with the Pan African Clinical Trials Registry (Trial ID: PACTR201310000589295).
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Trastornos Relacionados con Anfetaminas/terapia , Intervención en la Crisis (Psiquiatría)/métodos , Metanfetamina , Adulto , Estudios de Factibilidad , Femenino , Humanos , Terapia Implosiva/métodos , Análisis de Intención de Tratar , Masculino , Entrevista Motivacional/métodos , Sudáfrica/epidemiologíaRESUMEN
Given task-sharing mental health counselling to non-specialist providers is a recognised strategy to increase service capacity, ensuring that their training, supervision, and support needs are met is necessary to facilitate the sustainable delivery of a high-quality service. Using in-depth interviews, we qualitatively explored the experiences of 18 facility-based counsellors (FBCs) tasked with delivering a counselling intervention within chronic disease services offered within primary care facilities participating in the project MIND cluster randomised controlled trial. Findings show that project MIND training with a strong emphasis on role playing and skills rehearsal improved FBCs' confidence and competence, complemented by highly structured supervision and debriefing provided by a registered counsellor, were key strategies for supporting the implementation of task-shared mental health counselling. FBCs perceived many benefits to providing mental health counselling in primary healthcare but systemic interventions are needed for sustained implementation.
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Consejeros , Consejo , Humanos , Salud Mental , Intervención Psicosocial , SudáfricaRESUMEN
Most colorectal cancers show either microsatellite or chromosomal instability. A subset of colorectal cancers, especially those diagnosed at young age, is known to show neither of these forms of genetic instability and thus might have a distinct pathogenesis. Colorectal cancers diagnosed at young age are suggestive for hereditary predisposition. We investigate whether such early-onset microsatellite and chromosomally stable colorectal cancers are a hallmark of a genetic susceptibility syndrome. The ploidy status of microsatellite stable (familial) colorectal cancers of patients diagnosed before age 50 (n = 127) was analyzed in relation to the histopathological characteristics and family history. As a control the ploidy status of sporadic colorectal cancer, with normal staining of mismatch repair proteins, diagnosed at the age of 69 years or above (n = 70) was determined. A diploid DNA content was used as a marker for chromosomal stability. Within the group of patients with (familial) early onset microsatellite stable colorectal cancer the chromosomally stable tumors did not differ from chromosomally unstable tumors with respect to mean age at diagnosis, fulfillment of Amsterdam criteria or pathological characteristics. Segregation analysis did not reveal any family with microsatellite and chromosomally stable colorectal cancer in 2 relatives. The prevalence of microsatellite and chromosomally stable colorectal cancer was not significantly different for the early and late onset group (28 and 21%, respectively). We find no evidence that early-onset microsatellite and chromosomally stable colorectal cancer is a hallmark of a hereditary colorectal cancer syndrome.
Asunto(s)
Biomarcadores de Tumor/genética , Inestabilidad Cromosómica , Neoplasias Colorrectales/genética , Proteínas de Unión al ADN , Predisposición Genética a la Enfermedad , Repeticiones de Microsatélite/genética , Adulto , Edad de Inicio , Anciano , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Reparación del ADN/genética , Femenino , Citometría de Flujo , Mutación de Línea Germinal/genética , Humanos , Masculino , Persona de Mediana Edad , Países Bajos/epidemiologíaAsunto(s)
Proteínas de Unión al ADN/genética , Proteínas Proto-Oncogénicas/genética , Factores de Transcripción/genética , Translocación Genética , Secuencia de Bases , Humanos , Linfoma de Células B/genética , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-bcl-6RESUMEN
Pbx1 and a subset of homeodomain proteins collaboratively bind DNA as higher-order molecular complexes with unknown consequences for mammalian development. Pbx1 contributions were investigated through characterization of Pbx1-deficient mice. Pbx1 mutants died at embryonic day 15/16 with severe hypoplasia or aplasia of multiple organs and widespread patterning defects of the axial and appendicular skeleton. An obligatory role for Pbx1 in limb axis patterning was apparent from malformations of proximal skeletal elements, but distal structures were unaffected. In addition to multiple rib and vertebral malformations, neural crest cell-derived skeletal structures of the second branchial arch were morphologically transformed into elements reminiscent of first arch-derived cartilages. Although the skeletal malformations did not phenocopy single or compound Hox gene defects, they were restricted to domains specified by Hox proteins bearing Pbx dimerization motifs and unaccompanied by alterations in Hox gene expression. In affected domains of limbs and ribs, chondrocyte proliferation was markedly diminished and there was a notable increase of hypertrophic chondrocytes, accompanied by premature ossification of bone. The pattern of expression of genes known to regulate chondrocyte differentiation was not perturbed in Pbx1-deficient cartilage at early days of embryonic skeletogenesis, however precocious expression of Col1a1, a marker of bone formation, was found. These studies demonstrate a role for Pbx1 in multiple developmental programs and reveal a novel function in co-ordinating the extent and/or timing of proliferation with terminal differentiation. This impacts on the rate of endochondral ossification and bone formation and suggests a mechanistic basis for most of the observed skeletal malformations.
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Tipificación del Cuerpo , Huesos/embriología , Cartílago/embriología , Condrocitos/citología , Proteínas de Unión al ADN/metabolismo , Proteínas de Homeodominio/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Factores de Edad , Animales , Huesos/anomalías , Región Branquial/embriología , Cartílago/anomalías , Diferenciación Celular , División Celular , Cruzamientos Genéticos , Proteínas de Unión al ADN/genética , Genes Homeobox , Proteínas de Homeodominio/genética , Homocigoto , Ratones , Ratones Noqueados , Morfogénesis , Osteogénesis , Fenotipo , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Proteínas Proto-Oncogénicas/genéticaRESUMEN
Mammalian Pbx genes (Pbx1-3) encode a family of TALE homeodomain proteins that function as transcriptional regulators in numerous cell types (Curr. Opin. Genet. Dev. 8 (1998) 423). The present study highlights distinctive features of Pbx1b expression during mouse embryonic development as a framework to understand its biological functions. Immunohistochemical analyses demonstrate extensive expression of Pbx1b throughout post-implantation development, with highest levels observed during early to mid-gestation. Its initial distribution is predominantly associated with condensing mesoderm, however, Pbx1b displays dynamic expression patterns in derivatives of all principal germ layers. In particular, Pbx1b localizes to sites of mesenchymal-epithelial interactions during periods of active morphogenesis in tissues such as the lung, kidney, tooth buds and vibrissae follicles. Furthermore, BrdU labeling studies reveal that Pbx1b expression domains partially overlap with regions of cellular proliferation. Taken together, these data suggest that Pbx1b contributes to multiple cellular processes during embryogenesis, which may include roles in cell-autonomous regulation as well as in the mediation of tissue interactions.
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Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/genética , Animales , Bromodesoxiuridina/metabolismo , División Celular , Epitelio/embriología , Inmunohistoquímica , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Factores de TiempoRESUMEN
Specific Hox genes are implicated in leukemic transformation, and their selective genetic collaboration with TALE homeobox genes, Pbx and Meis, accentuates their oncogenic potential. The molecular mechanisms underlying these coordinate functions, however, have not been characterized. In this study, we demonstrate that HoxA9 requires its Pbx interaction motif as well as its amino terminus to enhance the clonogenic potential of myeloid progenitors in vitro. We further show that HoxA9 forms functional trimeric DNA binding complexes with Pbx and Meis-like proteins on a modified enhancer. DNA binding complexes containing HoxA9 and TALE homeoproteins display cooperative transcriptional activity and are present in leukemic cells. Trimeric complex formation on its own, however, is not sufficient for HoxA9-mediated immortalization. Rather, structure-function analyses demonstrate that domains of HoxA9 which are necessary for cellular transformation are coincident with those required for trimer-mediated transcriptional activation. Furthermore, the amino terminus of HoxA9 provides essential transcriptional effector properties and its requirement for myeloid transformation can be functionally replaced by the VP16 activation domain. These data suggest that biochemical interactions between HoxA9 and TALE homeoproteins mediate cellular transformation in hematopoietic cells, and that their transcriptional activity in higher order DNA binding complexes provides a molecular basis for their collaborative roles in leukemogenesis.
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Células Madre Hematopoyéticas/metabolismo , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/fisiología , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras , Secuencias de Aminoácidos , Animales , Biopolímeros/genética , Biopolímeros/metabolismo , División Celular/genética , Línea Celular , Línea Celular Transformada , Transformación Celular Neoplásica/patología , Proteínas de Unión al ADN/metabolismo , Células Madre Hematopoyéticas/patología , Células Madre Hematopoyéticas/fisiología , Proteínas de Homeodominio/química , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patología , Ratones , Ratones Endogámicos C57BL , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide , Proteínas de Neoplasias/química , Proteínas de Neoplasias/fisiología , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/fisiología , Células Tumorales CultivadasRESUMEN
Pbx/exd proteins modulate the DNA binding affinities and specificities of Hox proteins and contribute to the execution of Hox-dependent developmental programs in arthropods and vertebrates. Pbx proteins also stably heterodimerize and bind DNA with Meis and Pknox1-Prep1, additional members of the TALE (three-amino-acid loop extension) superclass of homeodomain proteins that function on common genetic pathways with a subset of Hox proteins. In this study, we demonstrated that Pbx and Meis bind DNA as heterotrimeric complexes with Hoxb1 on a genetically defined Hoxb2 enhancer, r4, that mediates the cross-regulatory transcriptional effects of Hoxb1 in vivo. The DNA binding specificity of the heterotrimeric complex for r4 is mediated by a Pbx-Hox site in conjunction with a distal Meis site, which we showed to be required for ternary complex formation and Meis-enhanced transcription. Formation of heterotrimeric complexes in which all three homeodomains bind their cognate DNA sites is topologically facilitated by the ability of Pbx and Meis to interact through their amino termini and bind DNA without stringent half-site orientation and spacing requirements. Furthermore, Meis site mutation in the Hoxb2 enhancer phenocopies Pbx-Hox site mutation to abrogate enhancer-directed expression of a reporter transgene in the murine embryonic hindbrain, demonstrating that DNA binding by all three proteins is required for trimer function in vivo. Our data provide in vitro and in vivo evidence for the combinatorial regulation of Hox and TALE protein functions that are mediated, in part, by their interdependent DNA binding activities as ternary complexes. As a consequence, Hoxb1 employs Pbx and Meis-related proteins, as a pair of essential cofactors in a higher-order molecular complex, to mediate its transcriptional effects on an endogenous Hox response element.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Factores de Transcripción/genética , Animales , Sitios de Unión , Células COS , Secuencia de Consenso , ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Dimerización , Proteínas de Homeodominio/química , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Transgénicos , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , Rombencéfalo/metabolismo , Soluciones , Transcripción GenéticaRESUMEN
The Pbx1 and Meis1 proto-oncogenes code for divergent homeodomain proteins that are targets for oncogenic mutations in human and murine leukemias, respectively, and implicated by genetic analyses to functionally collaborate with Hox proteins during embryonic development and/or oncogenesis. Although Pbx proteins have been shown to dimerize with Hox proteins and modulate their DNA binding properties in vitro, the biochemical compositions of endogenous Pbx-containing complexes have not been determined. In the present study, we demonstrate that Pbx and Meis proteins form abundant complexes that comprise a major Pbx-containing DNA binding activity in nuclear extracts of cultured cells and mouse embryos. Pbx1 and Meis1 dimerize in solution and cooperatively bind bipartite DNA sequences consisting of directly adjacent Pbx and Meis half sites. Pbx1-Meis1 heterodimers display distinctive DNA binding specificities and cross-bind to a subset of Pbx-Hox sites, including those previously implicated as response elements for the execution of Pbx-dependent Hox programs in vivo. Chimeric oncoprotein E2a-Pbx1 is unable to bind DNA with Meis1, due to the deletion of amino-terminal Pbx1 sequences following fusion with E2a. We conclude that Meis proteins are preferred in vivo DNA binding partners for wild-type Pbx1, a relationship that is circumvented by its oncogenic counterpart E2a-Pbx1.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Homeodominio/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas E2 de Adenovirus/genética , Proteínas E2 de Adenovirus/metabolismo , Animales , Sitios de Unión , Extractos Celulares , Núcleo Celular , Células Cultivadas , ADN/genética , ADN/metabolismo , Proteínas de Unión al ADN/genética , Dimerización , Proteínas de Homeodominio/genética , Humanos , Ratones , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide , Proteínas de Neoplasias/genética , Oligodesoxirribonucleótidos , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Proteínas Proto-Oncogénicas/genética , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
The chimeric oncoprotein E2a-Pbx1 results from fusion of the E2A and PBX1 genes following t(1;19) chromosomal translocations in B cell precursor acute leukemias. Experimentally B cell progenitors do not tolerate constitutive expression of E2a-Pbx1 which contrasts with transformation of several other cell types following its stable expression both in vitro and in vivo. To further investigate the effects of E2a-Pbx1 on the B cell progenitors, we conditionally expressed E2a-Pbx1 under control of a metal response element in hematopoietic precursor cell lines in vitro. Inducible expression of E2a-Pbx1 resulted in cell death with the morphologic and molecular features of apoptosis. A structure-function analysis demonstrated that induction of apoptosis was not a dominant-negative effect of the E2a moiety but, rather, required the DNA-binding homeodomain of Pbx1. E2a-Pbx1-induced apoptosis proceeded through a BCL2-responsive checkpoint eventuating in PARP inactivation but did require p53. Constitutive expression of E2a-Pbx1 did not induce apoptosis or continued cycling of Rat-1 fibroblasts in low serum conditions. These studies demonstrate that E2a-Pbx1 initiates programmed cell death of hematopoietic precursers by a mechanism that requires its chimeric transcriptional properties, but, unlike other nuclear oncoproteins, is independent of p53.
Asunto(s)
Apoptosis/fisiología , Células Madre Hematopoyéticas/citología , Proteínas de Homeodominio/fisiología , Proteínas de Fusión Oncogénica/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Proteínas Recombinantes de Fusión/fisiología , Proteína p53 Supresora de Tumor/fisiología , Animales , Apoptosis/efectos de los fármacos , Linfocitos B/citología , Linfocitos B/fisiología , Ciclo Celular/fisiología , Línea Celular , Fibroblastos/citología , Células HL-60/metabolismo , Células HL-60/fisiología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/fisiología , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/farmacología , Humanos , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/farmacología , Ratas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Relación Estructura-Actividad , Factores de Transcripción/fisiología , TransfecciónRESUMEN
The helix-loop-helix (HLH) transcription factors, Pan-1 (E47) and Pan-2 (E12), are produced by the mechanism of alternative transcript splicing. Pan-1 and Pan-2 were expressed in Escherichia coli, and a purification scheme was developed. Purified Pan-2 was used to immunize Smith-Webster mice and a hybridoma was generated that produced a monoclonal antibody (Yae) that specifically recognized both native and denatured Pan-1 and Pan-2. Deletion mapping and sequence transfer studies have localized the determinant recognized by the Yae antibody to the region 195-208 of Pan-2. This region is conserved in Pan-1 and Pan-2. The Yae antibody recognized in vitro-synthesized ITF-1, a third E2A (Pan) gene product also produced by the mechanism of alternative RNA splicing, but did not recognize the related HLH proteins, ITF-2, REB alpha, or REB beta. By Western blot assay of pancreatic acinar cells, the Yae antibody detected a single protein species of 72 kD that comigrated with in vitro-synthesized Pan-1 and Pan-2.
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Anticuerpos Monoclonales/inmunología , Proteínas de Unión al ADN/inmunología , Proteínas de Unión al ADN/aislamiento & purificación , Factores de Transcripción/inmunología , Factores de Transcripción/aislamiento & purificación , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Secuencia de Bases , Western Blotting , Línea Celular , Epítopos/inmunología , Escherichia coli/genética , Escherichia coli/metabolismo , Secuencias Hélice-Asa-Hélice , Ratones , Datos de Secuencia Molecular , Biosíntesis de Proteínas/genética , Ratas , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Factores de Transcripción TCF , Proteína 1 Similar al Factor de Transcripción 7 , Transcripción Genética/genéticaRESUMEN
A newly developed rat long-term bone marrow culture system was used to study the role of Pan/E2A basic helix-loop-helix transcription factors during B-cell development. In this system, B-lymphocyte progenitors actively differentiate into mature B cells. Monoclonal (Yae) and polyclonal (anti-Pan) antibodies were employed to characterize the expression of Pan proteins by Western blot assay during hematopoiesis and to examine the components of immunoglobulin heavy-chain gene enhancer element-binding species by electrophoretic mobility shift assay. During B-cell development, the appearance of Pan/E2A proteins preceded the expression of immunoglobulin heavy-chain protein. A Pan-containing immunoglobulin heavy-chain enhancer element (mu E5)-binding species (BCF1), composed of immunoreactive Pan-1/E47 but not Pan-2/E12, was observed concomitantly with the detection of Pan/E2A proteins. In addition to BCF1, other mu E5-binding species were detected which were not recognized by the Yae antibody. Two of these species were present in primary B-lymphocyte and myeloid cultures and were recognized by an anti-upstream stimulatory factor antiserum. Although Pan/E2A proteins have been proposed to be ubiquitous, Pan/E2A proteins were not detected in primary myeloid cultures composed mainly of granulocytes and macrophages or in the macrophage cell line J774. The absence of Pan/E2A proteins in differentiated myeloid cells correlated with low steady-state levels of Pan/E2A RNA. However, Pan/E2A proteins were present in a promyeloid cell line, 32DCL3, suggesting that extinction of Pan/E2A expression may play a role in myelopoiesis.
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Proteínas E2 de Adenovirus/biosíntesis , Linfocitos B/metabolismo , Proteínas de Unión al ADN/biosíntesis , Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Cadenas Pesadas de Inmunoglobulina/biosíntesis , Factores de Transcripción/biosíntesis , Proteínas E2 de Adenovirus/análisis , Animales , Anticuerpos , Anticuerpos Monoclonales , Linfocitos B/inmunología , Secuencia de Bases , Western Blotting , Médula Ósea/metabolismo , Células de la Médula Ósea , Línea Celular , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Proteínas de Unión al ADN/análisis , Elementos de Facilitación Genéticos , Células Madre Hematopoyéticas/inmunología , Cadenas Pesadas de Inmunoglobulina/análisis , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Biosíntesis de Proteínas , Ratas , Factores de Transcripción/análisis , Transcripción GenéticaRESUMEN
The Pan gene encodes at least two distinct transcripts, Pan-1 and Pan-2 (also known as E47 and E12, respectively), by the mechanism of alternative RNA splicing. Northern blot analyses performed on rat and mouse tissues have detected ubiquitously expressed Pan transcripts, but the abundance, distribution, and form of Pan proteins have not been clearly defined. Studies of cell lines representing endocrine, fibroblast, and lymphoid lineages using polyclonal antisera to detect E2A proteins have suggested that significant E2A protein expression is restricted to B-lymphocytes. We have developed a monoclonal antibody, Yae, which is specific for Pan/E2A proteins, and have used the Yae antibody to examine a variety of endocrine and nonendocrine cell lineages for differences in Pan/E2A protein expression, subcellular localization, and heteromeric complex formation. In contrast to previous results obtained using polyclonal antiseras to detect Pan/E2A proteins, we report comparable levels of Pan proteins in GH/PRL- and insulin-producing, B- and T-lymphocyte cells. IEF-1, a pancreatic beta-cell type-specific complex believed to regulate insulin expression, is demonstrated to consist of at least two distinct species, one of which does not contain Pan molecules. Although it has been postulated that pituitary endocrine cells and pancreatic endocrine beta-cells share identical Pan/E2A complexes, native-Western analyses of pituitary and endocrine beta-cells detect Pan proteins in distinct cell type-specific complexes.
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Proteínas de Unión al ADN/biosíntesis , Glándulas Endocrinas/metabolismo , Factores de Transcripción/biosíntesis , Animales , Anticuerpos Monoclonales , Secuencia de Bases , Western Blotting , Línea Celular , Cricetinae , Proteínas de Unión al ADN/fisiología , Electroforesis en Gel de Poliacrilamida , Glándulas Endocrinas/citología , Expresión Génica/fisiología , Humanos , Linfocitos/metabolismo , Datos de Secuencia Molecular , Ratas , Factores de Transcripción TCF , Proteína 1 Similar al Factor de Transcripción 7 , Factores de Transcripción/fisiologíaRESUMEN
A monoclonal antibody (Yae) was characterized and shown to specifically recognize E2A proteins in vivo, including the E2A-Pbx1 fusion gene products, p77E2A-Pbx1 and p85E2A-Pbx1. E2A proteins of a predominant molecular mass of 72 kDa, which comigrated with in vitro-produced rat E12 and and rat E47, were detected in human pro-B, pre-B, mature B, and plasma cell lines. The Yae antibody detected an E2A-containing microE2 enhancer element-binding complex (BCF-1) in pre-B- and mature B-cell lines in electrophoretic mobility shift assays which displayed a migration rate similar to that of in vitro-produced rat E12 and rat E47. A new E2A-containing microE2-binding species (P-E2A) was identified in plasma cells by using electrophoretic mobility shift assays. E2A proteins were detected in pro-B cells but were unable to bind the microE2 site. These observations suggest that the microE2 site is the target of stage-specific E2A regulatory complexes during B-cell development. Immunostaining analyses demonstrated the predominant nuclear localization of E2A proteins. Finally, we have identified an E2A form, designated I-E2A, which is unable to bind DNA. Our observations demonstrate novel in vivo mechanisms for the regulation of transcription by E2A proteins during B-cell development.
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Linfocitos B/metabolismo , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Factores de Transcripción , Animales , Anticuerpos Monoclonales , Linfocitos B/citología , Linfocitos B/inmunología , Secuencia de Bases , Diferenciación Celular , Línea Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/inmunología , Regulación de la Expresión Génica , Genes de Inmunoglobulinas , Humanos , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Células Plasmáticas/metabolismo , Ratas , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Células Madre/metabolismo , Factores de Transcripción TCF , Proteína 1 Similar al Factor de Transcripción 7RESUMEN
A homologous transformation system for Aspergillus oryzae is described. The system is based on an A. oryzae strain deficient in orotidine-5'-phosphate decarboxylase (pyrG) and the vector pAO4-2, which contains a functional A. oryzae pyrG gene as selection marker. Transformation of the A. oryzae pyrG mutant with circular pAO4-2 resulted in the appearance of Pyr+ transformants at a frequency of up to 20 per micrograms of DNA, whereas with linear pAO4-2 up to 200 transformants per micrograms DNA were obtained. In 75% of the Pyr+ transformants recombination events had occurred at the pyrG locus, most of which (90%) resulted in insertion of one or two copies of the vector and the others (10%) in a replacement of the mutant allele by the wild-type allele. Vector pAO4-2 is also capable of transforming a corresponding mutant of Aspergillus niger. This transformation system was used to introduce into A. oryzae the heterologous and non-selectable bacterial genes lacZ, encoding beta-galactosidase, and uidA, encoding beta-glucuronidase. Using the Aspergillus nidulans gpdA promoter to drive bacterial gene expression in A. oryzae, relatively high levels of activity, as well as protein per se, as judged by western blot analyses, were obtained.
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Aspergillus oryzae/genética , Aspergillus/genética , Carboxiliasas/genética , Genes Bacterianos/genética , Orotidina-5'-Fosfato Descarboxilasa/genética , Aspergillus niger/genética , Aspergillus oryzae/enzimología , Escherichia coli/genética , Galactosidasas/biosíntesis , Galactosidasas/genética , Glucuronidasa/biosíntesis , Glucuronidasa/genética , Proteínas Recombinantes de Fusión/biosíntesis , Transformación GenéticaRESUMEN
Diverticulosis of the appendix. Diverticulosis of the appendix is a rare condition. Cause of the danger of perforation, it is not an unimportant entity. We present six examples and review its pathogenesis, diagnosis and treatment.
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Apéndice , Divertículo/diagnóstico , Adulto , Apendicitis/etiología , Apéndice/cirugía , Enfermedades del Ciego/diagnóstico , Enfermedades del Ciego/cirugía , Divertículo/cirugía , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Patients may harbor cell-wall-deficient organisms or other aberrant bacterial forms (ABFs) in their eyes. In this survey of 400 cultures, we found the incidence of ABFs isolated from various ocular sites to be 13.2%. The rate of isolation of these forms from the eyes of patients with suspected bacterial infection differed greatly from that for noninfected eyes. We will describe the microbiological techniques employed and will present our analysis of the data obtained.
Asunto(s)
Formas Bacterianas Atípicas/aislamiento & purificación , Ojo/microbiología , Humor Acuoso/microbiología , Formas Bacterianas Atípicas/crecimiento & desarrollo , Infecciones Bacterianas/microbiología , Técnicas Bacteriológicas , Conjuntiva/microbiología , Medios de Cultivo , Oftalmopatías/microbiología , HumanosRESUMEN
Seminal fluid from males complaining of infertility was examined for the presence of T-mycoplasmas and Mycoplasma hominis. No significant difference, with regard to the presence of mycoplasmas, was found between the seminal fluid which had normal cytology and seminal fluid of which the cytology was deemed pathological. Colonisation was shown to be an evanescent phenomenon, and female consorts often had different mycoplasma flora to the males. No positive role of mycoplasmas in the pathogenesis of infertility could be shown.