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Failure, ubiquitous in life and medical practice, offers myriad opportunities for learning and growth alongside challenges to overall well-being. In this article, we explore the nature of failure, it's sources and impacts in perioperative medicine, and the specific challenges it brings to trainee well-being. With a deeper understanding of the societal, psychological and cognitive determinants and effects of failure, we propose solutions in order to harness the opportunities inherent in failures to create brave and supportive learning environments conducive to both education and well-being.
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Anestesiología , Aprendizaje , Medicina Perioperatoria , Humanos , Anestesiología/educación , Medicina Perioperatoria/métodosRESUMEN
The National Diabetes Stakeholders Covid-19 Response Group was formed in early April 2020 as a rapid action by the Joint British Diabetes Societies for Inpatient Care, Diabetes UK, the Association of British Clinical Diabetologists, and Diabetes Frail to address and support the special needs of residents with diabetes in UK care homes during Covid-19. It was obvious that the care home sector was becoming a second wave of Covid-19 infection and that those with diabetes residing in care homes were at increased risk not only of susceptibility to infection but also to poorer outcomes. Its key purposes included minimising the morbidity and mortality associated with Covid-19 and assisting care staff to identify those residents with diabetes at highest risk of Covid-19 infection. The guidance was particularly created for care home managers, other care home staff, and specialist and non-specialist community nursing teams. The guidance covers the management of hyperglycaemia by discussion of various clinical scenarios that could arise, the management of hypoglycaemia, foot care and end of life care. In addition, it outlines the conditions where hospital admission is required. The guidance should be regarded as interim and will be updated as further medical and scientific evidence becomes available.
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Infecciones por Coronavirus/terapia , Atención a la Salud/métodos , Diabetes Mellitus/terapia , Casas de Salud , Neumonía Viral/terapia , Betacoronavirus , COVID-19 , Comorbilidad , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/metabolismo , Complicaciones de la Diabetes/epidemiología , Diabetes Mellitus/epidemiología , Manejo de la Enfermedad , Fragilidad , Glucocorticoides/uso terapéutico , Humanos , Esperanza de Vida , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/metabolismo , Factores de Riesgo , SARS-CoV-2 , Reino Unido/epidemiologíaRESUMEN
The UK National Diabetes Inpatient COVID Response Group was formed at the end of March 2020 to support the provision of diabetes inpatient care during the COVID pandemic. It was formed in response to two emerging needs. First to ensure that basic diabetes services are secured and maintained at a time when there was a call for re-deployment to support the need for general medical expertise across secondary care services. The second was to provide simple safe diabetes guidelines for use by specialists and non-specialists treating inpatients with or suspected of COVID-19 infection. To date the group, comprising UK-based specialists in diabetes, pharmacy and psychology, have produced two sets of guidelines which will be continually revised as new evidence emerges. It is supported by Diabetes UK, the Association of British Clinical Diabetologists and NHS England.
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Infecciones por Coronavirus/terapia , Atención a la Salud/métodos , Diabetes Mellitus/terapia , Hospitalización , Neumonía Viral/terapia , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/metabolismo , Diabetes Mellitus/epidemiología , Manejo de la Enfermedad , Humanos , Pandemias , Readmisión del Paciente , Neumonía Viral/epidemiología , Neumonía Viral/metabolismo , SARS-CoV-2 , Reino Unido/epidemiologíaRESUMEN
PURPOSE: Malnutrition (MN) in cancer is common but underdiagnosed. Dietitian referrals may not occur until MN is established. We investigated cancer patient characteristics (demographics, nutritional status, and nutrition barriers) on referral to oncology dietitians. We also examined referral practices and prevalence of missed referral opportunities. METHODS: This was a naturalistic multi-site study of clinical practice. Data from consecutive referrals were collected in inpatient and outpatient settings. Demographics, nutritional status (weight, body mass index (BMI), weight loss in the preceding 3-6 months, oral intake, nutrition barriers), referral reasons, and use of screening were recorded. Missed opportunities for earlier referral were also noted. RESULTS: Two hundred patients were included (60% male, 51% inpatients). Half had gastrointestinal and hepatobiliary cancers. The majority were on antitumor treatment. Two-thirds had lost ≥ 5% body weight. Forty percent were overweight or obese. Seventy percent had ≥ 2 nutritional barriers. Most common nutrition barriers were anorexia, nausea, and early satiety. Greater weight loss and lower food intake were associated with ≥ 2 barriers. Weight loss was the most common referral reason. Screening was used in 35%. Referrals should have occurred sooner in nearly half (45%, n = 89). CONCLUSIONS: Cancer patients were referred late to a dietitian, with multiple nutritional barriers. Most referrals were for established weight loss (WL). WL may be masked by pre-existing obesity. Almost half had missed earlier referral opportunities; screening was infrequent. Over one-quarter should have been re-referred sooner. There is a clear need for clinician education. Future research should investigate the optimal timing of dietitian referral and the best nutrition screening tools for use in cancer.
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Desnutrición/diagnóstico , Desnutrición/terapia , Estado Nutricional/fisiología , Nutricionistas/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Adulto , Índice de Masa Corporal , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Náusea , Neoplasias/complicaciones , Obesidad/complicaciones , Pacientes Ambulatorios , Pautas de la Práctica en Medicina , Prevalencia , Estudios Prospectivos , Pérdida de PesoRESUMEN
AIM: To examine, in a national survey, the outcomes of adult patients presenting with DKA in 2014, mapped against accepted UK national guidance. METHODS: Data were collected in a standardized form covering clinical and biochemical outcomes, risk and discharge planning. The form was sent to all UK diabetes specialist teams (n = 220). Anonymized data were collected on five consecutive patients admitted with DKA between 1 May 2014 and 30 November 2014. RESULTS: A total of 283 forms were received (n = 281 patients) from 72 hospitals, of which 71.4% used the national guidelines. The results showed that 7.8% of cases occurred in existing inpatients, 6.1% of admissions were newly diagnosed diabetes and 33.7% of patients had had at least one episode of DKA in the preceding year. The median times to starting 0.9% sodium chloride and intravenous insulin were 41.5 and 60 min, respectively. The median time to resolution was 18.7 h and the median length of hospital stay was 2.6 days. Significant adverse biochemical outcomes occurred, with 27.6% of patients developing hypoglycaemia and 55% reported as having hypokalaemia. There were also significant issues with care processes. Initial nurse-led observations were carried out well, but subsequent patient monitoring remained suboptimal. Most patients were not seen by a member of the diabetes specialist team during the first 6 h, but 95% were seen before discharge. A significant minority of discharge letters to primary care did not contain necessary information. CONCLUSION: Despite widespread adoption of national guidance, several areas of management of DKA are suboptimal, being associated with avoidable biochemical and clinical risk.
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Cetoacidosis Diabética/terapia , Adhesión a Directriz , Alta del Paciente , Adulto , Estudios de Cohortes , Terapia Combinada/normas , Anonimización de la Información , Cetoacidosis Diabética/epidemiología , Cetoacidosis Diabética/enfermería , Cetoacidosis Diabética/prevención & control , Femenino , Encuestas de Atención de la Salud , Humanos , Tiempo de Internación , Masculino , Enfermeras Clínicas , Grupo de Atención al Paciente , Guías de Práctica Clínica como Asunto , Mejoramiento de la Calidad , Calidad de la Atención de Salud , Recurrencia , Riesgo , Especialización , Medicina Estatal , Reino Unido/epidemiologíaAsunto(s)
Tratamiento Farmacológico de COVID-19 , Dexametasona/administración & dosificación , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología , Control Glucémico/métodos , SARS-CoV-2 , COVID-19/epidemiología , Comorbilidad , Dexametasona/efectos adversos , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/prevención & control , Insulina Isófana/administración & dosificaciónAsunto(s)
Diabetes Mellitus , Hiperglucemia , Betacoronavirus , COVID-19 , Infecciones por Coronavirus , Humanos , Pacientes Internos , Pandemias , Neumonía Viral , SARS-CoV-2Asunto(s)
Betacoronavirus , Cetoacidosis Diabética , Neumonía Viral , COVID-19 , Infecciones por Coronavirus , Humanos , Pandemias , SARS-CoV-2RESUMEN
CCL2 is an important inflammatory chemokine involved in monocyte recruitment to inflamed tissues. The extracellular nucleotide signalling molecules UTP and ATP acting via the P2Y2 receptor are known to induce CCL2 secretion in macrophages. We confirmed this in the human THP-1 monocytic cell line showing that UTP is as efficient as LPS at inducing CCL2 at early time points (2-6 hours). Expression and calcium mobilisation experiments confirmed the presence of functional P2Y2 receptors on THP-1 cells. UTP stimulation of human peripheral CD14+ monocytes showed low responses to LPS (4-hour stimulation) but a significant increase above background following 6 hours of treatment. The response to UTP in human monocytes was variable and required stimulation >6 hours. With such variability in response we looked for single nucleotide polymorphisms in P2RY2 that could affect the functional response. Sequencing of P2RY2 from THP-1 cells revealed the presence of a single nucleotide polymorphism altering amino acid 312 from arginine to serine (rs3741156). This polymorphism is relatively common at a frequency of 0.276 (n = 404 subjects). Finally, we investigated CCL2 secretion in response to LPS or UTP in human macrophages expressing 312Arg-P2Y2 or 312Ser-P2Y2 where only the latter exhibited significant UTP-induced CCL2 secretion (n = 5 donors per group).
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Quimiocina CCL2/metabolismo , Macrófagos/metabolismo , Monocitos/metabolismo , Nucleótidos/metabolismo , Receptores Purinérgicos P2Y2/metabolismo , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Genotipo , Humanos , Receptores de Lipopolisacáridos , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Polimorfismo de Nucleótido Simple/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Uridina Trifosfato/farmacologíaRESUMEN
We report a man with lifelong urticaria, night sweats, arthralgia and lethargy. He had high levels of inflammatory markers and serum amyloid A, but no identifiable mutation in exon 3 of the NLRP3 (NOD-like receptor family, pyrin domain-1 containing 3) gene, and no relevant family history. We found marked production of functional interleukin (IL)-1 by the patient's monocytes at baseline and after stimulation with lipopolysaccharide. The patient made an immediate response to treatment with an IL-1ß receptor antagonist. We propose that this patient has Muckle-Wells syndrome without deafness, occurring de novo. Functional screening for IL-1 production could aid diagnosis in future similar cases.
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Antirreumáticos/uso terapéutico , Proteínas Portadoras/genética , Síndromes Periódicos Asociados a Criopirina/tratamiento farmacológico , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Interleucina-1beta/metabolismo , Monocitos/metabolismo , Síndromes Periódicos Asociados a Criopirina/genética , Síndromes Periódicos Asociados a Criopirina/metabolismo , Exones/genética , Humanos , Masculino , Persona de Mediana Edad , Proteína con Dominio Pirina 3 de la Familia NLR , Resultado del TratamientoRESUMEN
Loss-of-function mutations in the gene (CSTB) encoding human cystatin B, a widely expressed cysteine protease inhibitor, are responsible for a severe neurological disorder known as Unverricht-Lundborg disease (EPM1). The primary cellular events and mechanisms underlying the disease are unknown. We found that mice lacking cystatin B develop myoclonic seizures and ataxia, similar to symptoms seen in the human disease. The principal cytopathology appears to be a loss of cerebellar granule cells, which frequently display condensed nuclei, fragmented DNA and other cellular changes characteristic of apoptosis. This mouse model of EPM1 provides evidence that cystatin B, a non-caspase cysteine protease inhibitor, has a role in preventing cerebellar apoptosis.
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Apoptosis/genética , Ataxia/genética , Cerebelo/patología , Cistatinas/deficiencia , Cistatinas/genética , Inhibidores de Cisteína Proteinasa/deficiencia , Inhibidores de Cisteína Proteinasa/genética , Epilepsias Mioclónicas/genética , Secuencia de Aminoácidos , Animales , Ataxia/patología , Secuencia de Bases , Opacidad de la Córnea/genética , Cistatina B , Cistatinas/fisiología , Inhibidores de Cisteína Proteinasa/fisiología , Cartilla de ADN/genética , Modelos Animales de Enfermedad , Epilepsias Mioclónicas/patología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Noqueados , Modelos Genéticos , Mutación , FenotipoRESUMEN
INTRODUCTION: Patients receiving stereotactic body radiotherapy (SBRT) for early-stage non-small cell lung cancer (NSCLC) are typically inoperable, in concordance with guidelines that advocate surgical resection as preferred treatment for operable patients. This differential treatment allocation complicates retrospective comparisons of surgery with SBRT by introducing the potential for confounding by operability. METHODS: PubMed was queried for manuscripts reporting primary data from retrospective comparisons of overall survival (OS) between patients undergoing surgery versus SBRT for early-stage NSCLC. Each manuscript was categorized for two outcomes: (1) whether treatment allocation was based on a determination of patient operability, and (2) whether a direct OS comparison between operable SBRT patients and surgically treated patients was included. Associations with variables of interest were measured with statistical significance prespecified at p < 0.10. RESULTS: From 3,072 manuscripts identified in our query, sixty-one analyses met screening criteria. Twenty-one (34 %) reported operability status influencing treatment allocation. These were more likely to be published in journals with a surgical focus (52 vs 20 %) and impact factor < 5 (81 vs 58 %), and to contain cohorts from institutional datasets (81 vs 55 %), and to have a radiation oncologist as first (43 vs 25 %) or senior (43 vs 28 %) author. Seven (11 %) manuscripts featured a direct OS comparison between SBRT and surgery. CONCLUSION: Nearly-two-thirds of peer-reviewed retrospective studies that have compared OS between surgery and SBRT for early-stage NSCLC lack information on patient operability status, and nearly 90% lack a direct comparison between operable SBRT patients and those receiving surgery.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radiocirugia , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirugía , Estudios Retrospectivos , Radiocirugia/efectos adversos , Estadificación de NeoplasiasRESUMEN
Most studies examining endophytic fungi associated with grasses (Poaceae) have focused on agronomically important species in managed ecosystems or on wild grasses in subtropical, temperate and boreal grasslands. However grasses first arose in tropical forests, where they remain a significant and diverse component of understory and forest-edge communities. To provide a broader context for understanding grass-endophyte associations we characterized fungal endophyte communities inhabiting foliage of 11 species of phylogenetically diverse C(3) grasses in the understory of a lowland tropical forest at Barro Colorado Island, Panama. Our sample included members of early-arising subfamilies of Poaceae that are endemic to forests, as well as more recently arising subfamilies that transitioned to open environments. Isolation on culture media and direct PCR and cloning revealed that these grasses harbor species-rich and phylogenetically diverse communities that lack the endophytic Clavicipitaceae known from diverse woodland and pasture grasses in the temperate zone. Both the incidence and diversity of endophytes was consistent among grass species regardless of subfamily, clade affiliation or ancestral habitat use. Genotype and phylogenetic analyses suggest that these endophytic fungi are predominantly host generalists, shared not only among distinctive lineages of Poaceae but also with non-grass plants at the same site.
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Biodiversidad , Hongos/aislamiento & purificación , Hongos/fisiología , Especificidad del Huésped , Poaceae/microbiología , Simbiosis , ADN de Hongos , Hongos/clasificación , Hongos/genética , Datos de Secuencia Molecular , Filogenia , Poaceae/clasificación , Poaceae/fisiología , Reacción en Cadena de la Polimerasa , Clima TropicalRESUMEN
The gp120 envelope glycoprotein of human immunodeficiency virus type 1 (HIV-1) is a dominant target against which the host's humoral immune response is directed. Unfortunately, gp120 proteins from different isolates of HIV are antigenically distinct, complicating the use of the envelope glycoprotein in vaccines designed to prevent acquired immunodeficiency syndrome. Using an enzyme-linked immunosorbent spot assay (ELISA), BALB/c mice immunized and boosted with recombinant purified gp120 were studied at the single cell level for their humoral immune response to HIV-1 envelope proteins. Approximately 90% of responding B cells produced antibodies reactive with the immunizing form of gp120 but not with gp120s from other strains of HIV. A novel sandwich ELISA was then used to analyze the frequency with which individual in vivo activated B cells produced antibodies that crossreacted with heterologous gp120s. Repeated immunizations with a single gp120 or with a mixture of different gp120s resulted in the activation of primarily mono-specific (noncrossreactive) B cells. In contrast, the sequential immunization of mice with recombinant purified envelope proteins from different strains of HIV (IIIB, SF2, and Zr6) induced the selective expansion of B cells producing highly crossreactive antibodies.
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Linfocitos B/inmunología , Anticuerpos Anti-VIH/biosíntesis , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Animales , Especificidad de Anticuerpos , Reacciones Cruzadas , Proteína gp120 de Envoltorio del VIH/administración & dosificación , Esquemas de Inmunización , Memoria Inmunológica , Ratones , Ratones Endogámicos BALB C , Proteínas RecombinantesRESUMEN
During thymic maturation, CD4-CD8-TCR- immature thymocytes differentiate through a CD4+CD8+TCRlo intermediate into two functionally distinct mature T cell subsets: helper T cells expressing CD4 and a major histocompatibility complex (MHC) class II-restricted T cell receptor (TCR), and cytotoxic T cells expressing CD8 and and MHC class I-restricted TCR. The mutually exclusive expression of CD4 and CD8 is maintained in the periphery during expansion of these mature T cell subsets. To elucidate the mechanisms controlling CD4 and CD8 expression on differentiating thymocytes and mature peripheral T cells, we have examined the expression of human CD4 gene constructs in the lymphoid tissues of transgenic mice. Our analyses demonstrate that sequences contained within or closely linked to the human CD4 gene are sufficient to reconstitute the appropriate regulation of human CD4 expression on all thymocyte and mature peripheral T cell subsets. Specifically, appropriate developmental regulation was dependent on two sets of sequences, one contained within a 1.3-kb restriction fragment located 6.5 kb upstream of the human CD4 gene, and the other present within or immediately flanking the gene. Nucleotide sequence analysis identified the 1.3-kb restriction fragment as the likely human homologue of an enhancer found 13 kb upstream of the mouse CD4 transcription initiation site. The human CD4 transgenic mice provide a useful system for the identification and characterization of additional sequence elements that participate in human CD4 gene regulation and for the elucidation of regulatory mechanisms governing the developmental program mediating the maturation of the CD4+ and CD8+ peripheral T cell subsets.
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Antígenos CD4/genética , Linfocitos T CD4-Positivos/inmunología , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Timo/inmunología , Animales , Linfocitos B/inmunología , Secuencia de Bases , Antígenos CD4/biosíntesis , Linfocitos T CD4-Positivos/citología , Diferenciación Celular , ADN , Humanos , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Bazo/citología , Bazo/inmunología , Timo/citologíaRESUMEN
Fungi associated with photosynthetic organisms are major determinants of terrestrial biomass, nutrient cycling, and ecosystem productivity from the poles to the equator. Whereas most fungi are known because of their fruit bodies (e.g., saprotrophs), symptoms (e.g., pathogens), or emergent properties as symbionts (e.g., lichens), the majority of fungal diversity is thought to occur among species that rarely manifest their presence with visual cues on their substrate (e.g., the apparently hyperdiverse fungal endophytes associated with foliage of plants). Fungal endophytes are ubiquitous among all lineages of land plants and live within overtly healthy tissues without causing disease, but the evolutionary origins of these highly diverse symbionts have not been explored. Here, we show that a key to understanding both the evolution of endophytism and the diversification of the most species-rich phylum of Fungi (Ascomycota) lies in endophyte-like fungi that can be isolated from the interior of apparently healthy lichens. These "endolichenic" fungi are distinct from lichen mycobionts or any other previously recognized fungal associates of lichens, represent the same major lineages of Ascomycota as do endophytes, largely parallel the high diversity of endophytes from the arctic to the tropics, and preferentially associate with green algal photobionts in lichen thalli. Using phylogenetic analyses that incorporate these newly recovered fungi and ancestral state reconstructions that take into account phylogenetic uncertainty, we show that endolichenism is an incubator for the evolution of endophytism. In turn, endophytism is evolutionarily transient, with endophytic lineages frequently transitioning to and from pathogenicity. Although symbiotrophic lineages frequently give rise to free-living saprotrophs, reversions to symbiosis are rare. Together, these results provide the basis for estimating trophic transition networks in the Ascomycota and provide a first set of hypotheses regarding the evolution of symbiotrophy and saprotrophy in the most species-rich fungal phylum. [Ancestral state reconstruction; Ascomycota; Bayesian analysis; endolichenic fungi; fungal endophytes; lichens; pathogens; phylogeny; saprotrophy; symbiotrophy; trophic transition network.].
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Ascomicetos , Evolución Biológica , Líquenes/microbiología , Plantas/microbiología , SimbiosisRESUMEN
Simple discrete-time ecological models for a species with alternating reproduction and dispersal are shown to have complex transient dynamics. If the density dependence (nonlinearity) is strong enough, then the time required to reach the final dynamics is usually very long, approaching thousands of generations, and there are typically very sudden changes in the form of the dynamics. Apparent chaos can change to cycles or vice versa. These results are consistent with observed sudden changes in the form of the dynamics of a single species and imply that transient dynamics of ecological models may be more relevant than long-term behavior.
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Transcription factor NF-kappa B comprises two proteins, p50 and p65, that have sequence similarity to the v-rel oncogene. In primary hematopoietic cell populations an alternatively spliced form of NF-kappa B p65 mRNA was observed that encoded a protein designated p65 delta. Expression of the p65 delta cDNA in Rat-1 fibroblasts resulted in focus formation, anchorage-independent growth in soft agar, and tumor formation in athymic nude mice, effects not obtained with expression of p65 or a p65 delta mutant that contains a disruption within the transcriptional activation domain. Thus, p65 delta, which associated weakly and interfered with DNA binding by p65, may sequester an essential limiting regulatory factor or factors required for NF-kappa B function.
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Transformación Celular Neoplásica/genética , Variación Genética , FN-kappa B/genética , Animales , Secuencia de Bases , Sitios de Unión , ADN/genética , ADN/metabolismo , Fibroblastos/metabolismo , Células Madre Hematopoyéticas/química , Humanos , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Trasplante de Neoplasias , Proteínas Oncogénicas v-rel , Reacción en Cadena de la Polimerasa , Empalme del ARN , ARN Mensajero/análisis , ARN Mensajero/genética , Ratas , Proteínas Oncogénicas de Retroviridae/genética , TransfecciónRESUMEN
The PATCHED (PTC) gene encodes a Sonic hedgehog (Shh) receptor and a tumor suppressor protein that is defective in basal cell nevus syndrome (BCNS). Functions of PTC were investigated by inactivating the mouse gene. Mice homozygous for the ptc mutation died during embryogenesis and were found to have open and overgrown neural tubes. Two Shh target genes, ptc itself and Gli, were derepressed in the ectoderm and mesoderm but not in the endoderm. Shh targets that are, under normal conditions, transcribed ventrally were aberrantly expressed in dorsal and lateral neural tube cells. Thus Ptc appears to be essential for repression of genes that are locally activated by Shh. Mice heterozygous for the ptc mutation were larger than normal, and a subset of them developed hindlimb defects or cerebellar medulloblastomas, abnormalities also seen in BCNS patients.
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Sistema Nervioso Central/embriología , Neoplasias Cerebelosas/genética , Regulación del Desarrollo de la Expresión Génica , Meduloblastoma/genética , Proteínas de la Membrana/genética , Anomalías Múltiples/genética , Animales , Tipificación del Cuerpo , Linaje de la Célula , Sistema Nervioso Central/citología , Neoplasias Cerebelosas/patología , Ectodermo/metabolismo , Endodermo/metabolismo , Genes Supresores de Tumor , Heterocigoto , Homocigoto , Péptidos y Proteínas de Señalización Intracelular , Meduloblastoma/patología , Proteínas de la Membrana/fisiología , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Mutación , Proteínas Oncogénicas/genética , Receptores Patched , Receptor Patched-1 , Receptores de Superficie Celular , Transactivadores , Factores de Transcripción/genética , Proteína con Dedos de Zinc GLI1RESUMEN
One action of cyclosporin A thought to be central to many of its immunosuppressive effects is its ability to inhibit the early events of T lymphocyte activation such as lymphokine gene transcription in response to signals initiated at the antigen receptor. Cyclosporin A was found to specifically inhibit the appearance of DNA binding activity of NF-AT, AP-3, and to a lesser extent NF-kappa B, nuclear proteins that appear to be important in the transcriptional activation of the genes for interleukin-2 and its receptor, as well as several other lymphokines. In addition, cyclosporin A abolished the ability of the NF-AT binding site to activate a linked promoter in transfected mitogen-stimulated T lymphocytes and in lymphocytes from transgenic mice. These results indicate that cyclosporin A either directly inhibits the function of nuclear proteins critical to T lymphocyte activation or inhibits the action of a more proximal member of the signal transmission cascade leading from the antigen receptor to the nucleus.