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1.
J Intensive Care Soc ; 23(3): 325-333, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36033241

RESUMEN

FUSIC haemodynamics (HD) - the latest Focused Ultrasound in Intensive Care (FUSIC) module created by the Intensive Care Society (ICS) - describes a complete haemodynamic assessment with ultrasound based on ten key clinical questions: 1. Is stroke volume abnormal? 2. Is stroke volume responsive to fluid, vasopressors or inotropes? 3. Is the aorta abnormal? 4. Is the aortic valve, mitral valve or tricuspid valve severely abnormal? 5. Is there systolic anterior motion of the mitral valve? 6. Is there a regional wall motion abnormality? 7. Are there features of raised left atrial pressure? 8. Are there features of right ventricular impairment or raised pulmonary artery pressure? 9. Are there features of tamponade? 10. Is there venous congestion? FUSIC HD is the first system of its kind to interrogate major cardiac, arterial and venous structures to direct time-critical interventions in acutely unwell patients. This article explains the rationale for this accreditation, outlines the training pathway and summarises the ten clinical questions. Further details are included in an online supplementary appendix.

2.
Chronic Obstr Pulm Dis ; 7(3): 151-162, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32726073

RESUMEN

BACKGROUND: Alpha-1 antitrypsin deficiency (AATD) is an important, inherited cause of chronic liver disease. Marked variation in fibrosis stages in patients with homozygous deficiency and those factors that determine whether heterozygous carriers develop liver fibrosis, remain unexplained. Murine studies implicate polymerized alpha-1 antitrypsin (AAT) within hepatocytes as pathogenic. AIMS AND METHODS: The relationship between the quantity of polymerized AAT within hepatocytes (polymer load), stage of hepatic fibrosis and liver-related clinical outcomes (death, evolution to hepatocellular carcinoma, or need for liver transplantation) were investigated using liver tissue from 92 patients at first presentation with either homozygous or heterozygous AATD. Further tissue-based studies were undertaken to determine if polymerized AAT was associated with failure of cell cycle progression, accelerated aging or hepatocyte senescence by immunohistochemical analysis. RESULTS: The AAT polymer load correlated closely with hepatic fibrosis stage and long-term clinical outcome, independent of homozygous or heterozygous status. AAT polymers within hepatocytes correlated closely with failure of cell cycle progression assessed using cell cycle phase markers, accelerated aging manifest as shortened telomeres and other markers consistent with hepatocyte senescence manifest as the presence of nuclear p21 expression and enlarged nuclei. The proportion of p21 positive hepatocytes or hepatocytes with enlarged nuclei correlated with hepatic fibrosis stage and the long-term clinical outcome. CONCLUSION: These data suggest that accumulation of AAT polymers within hepatocytes drives senescence. Quantitation of both the AAT polymer load or hepatocyte senescence markers correlated with hepatic fibrosis stage and the long-term clinical outcome. Either or both could be considered markers of disease severity and treatment response in clinical trials.

3.
J Hepatol ; 58(3): 549-56, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23142622

RESUMEN

BACKGROUND & AIMS: Models of non-alcohol-related fatty liver disease (NAFLD) reveal features of accelerated ageing, such as impaired regeneration, and an increased risk of hepatocellular carcinoma. The relation between accelerated ageing, disease progression and clinical outcome has not been previously investigated and is the subject of the current study. METHODS: Liver sections from 70 patients with NAFLD (105 biopsies) and 60 controls were studied for telomere length, nuclear area, DNA damage and cell cycle phase markers, using quantitative fluorescent in situ hybridization and immunohistochemistry. RESULTS: Hepatocyte telomeres were shorter in NAFLD than controls (p <0.0001). Hepatocytes in NAFLD demonstrated lack of cell cycle progression beyond G1/S phase and high-level expression of p21, the universal cell cycle inhibitor (p=0.001). γ-H(2)AX expression increased with steatosis (p=0.01), indicating DNA damage, and was associated with shorter hepatocyte telomeres (p <0.0001). Hepatocyte p21 expression correlated with fibrosis stage and diabetes mellitus, independently (p <0.001 and p=0.002, respectively). Further analysis revealed that an adverse liver-related outcome was strongly associated with higher hepatocyte p21 expression and greater hepatocyte nuclear area (p=0.02 and p=0.006), but not with telomere length. In paired biopsies, changes in hepatocyte p21 expression and nuclear area mirrored changes in fibrosis stage (p=0.01 and p=0.006, respectively). CONCLUSIONS: These findings are consistent with hepatocyte senescence and permanent cell cycle arrest in NAFLD. Hepatocyte senescence correlated closely with fibrosis stage, diabetes mellitus, and clinical outcome. Hepatocyte p21 expression could be used as a prognostic marker and for stratification in clinical studies.


Asunto(s)
Senescencia Celular , Hígado Graso/patología , Hepatocitos/patología , Adulto , Anciano , Biopsia , Núcleo Celular/patología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/análisis , Progresión de la Enfermedad , Femenino , Histonas/análisis , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Telómero
4.
Hepatology ; 56(4): 1510-20, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22504828

RESUMEN

UNLABELLED: Telomeres, a validated biomarker of aging, comprise multiple nucleotide repeats capping chromosomes that shorten with each cell cycle until a critical length is achieved, precipitating cell senescence. Only two previous studies focused on the effect of aging in "normal" liver tissue, but these studies were compromised by small sample size, limited age range, tissue derived from individuals with an increased risk of senescence, and the use of liver homogenates. We developed a robust large-volume, four-color quantitative fluorescent in situ hybridization technique to measure telomere length in large numbers of hepatocytes, Kupffer cells, hepatic stellate cells, CD4-positive and CD8-positive lymphocytes, and cholangiocytes. Following validation against the gold standard (Southern blotting), the technique was applied to normal archived paraffin-embedded liver tissue obtained following reperfusion of implanted donor liver. We studied 73 highly selected donors aged 5-79 years with a short medical illness preceding death and no history of liver disease, reperfusion injury, or steatosis and normal graft function 1-year posttransplantation. Cholangiocytes had significantly longer telomeres compared with all other intrahepatic lineages over a wide age range (P < 0.05). Age-related telomere attrition was restricted to sinusoidal cells (i.e., Kupffer cells [P = 0.0054] and stellate cells [P = 0.0001]). Cholangiocytes and hepatocytes showed no age-related telomere shortening. CONCLUSION: In normal liver and over a broad age range, cholangiocytes have longer telomeres than all other intrahepatic lineages. Age-related telomere length decline is restricted to Kupffer cells and stellate cells.


Asunto(s)
Envejecimiento/genética , Conductos Biliares/citología , Senescencia Celular/genética , Hepatocitos/fisiología , Hígado/patología , Telómero/genética , Adolescente , Adulto , Anciano , Conductos Biliares/fisiología , Células Cultivadas , Preescolar , Femenino , Hepatocitos/metabolismo , Humanos , Hibridación Fluorescente in Situ , Macrófagos del Hígado/citología , Macrófagos del Hígado/fisiología , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Valores de Referencia , Reproducibilidad de los Resultados , Medición de Riesgo , Muestreo , Sensibilidad y Especificidad , Telómero/fisiología , Acortamiento del Telómero/genética , Adulto Joven
5.
J Clin Pathol ; 65(6): 557-60, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22447919

RESUMEN

Hepatocyte nuclear vacuolation is considered benign and associated with non-alcohol-related fatty liver disease. Vacuolated hepatocyte nuclei were compared with non-vacuolated hepatocyte nuclei in eight patients with advanced fibrosis and a spectrum of liver disease to explore the hypothesis that such nuclei represent senescence. Age- and sex-matched liver donors served as normal tissue. In normal liver <0.01% hepatocytes showed nuclear vacuolation. In contrast, nuclear vacuolation was present in all patients with liver disease, ranging from 0.1% to 11.7% hepatocytes, irrespective of the aetiology of liver disease and independent of insulin resistance. There was a close association between nuclear vacuolation and increased nuclear area, p21 expression, γ H(2)AX expression and the absence of Mcm-2, consistent with senescence and cell cycle arrest. Nuclear vacuolation in hepatocytes is a marker of senescence and likely to be a consequence of liver injury, unrelated to insulin resistance.


Asunto(s)
Envejecimiento/patología , Núcleo Celular/patología , Hepatocitos/patología , Vacuolas/patología , Adulto , Anciano , Biomarcadores/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Daño del ADN , Femenino , Histonas/genética , Histonas/metabolismo , Humanos , Hibridación Fluorescente in Situ , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad
6.
J Virol ; 86(11): 6358-64, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22457518

RESUMEN

Infection with human papillomavirus type 16 (HPV-16) can lead to low- or high-grade squamous intraepithelial lesions (LSIL or HSIL). Here we show that these in vivo disease states can be replicated in raft cultures of early-pass HPV-16 episomal cell lines, at both the level of pathology and the level of viral gene expression. A reduced responsiveness to cell-cell contact inhibition and an increase in E6/E7 activity correlated closely with phenotype. Similar deregulation is likely to underlie the appearance of LSIL or HSIL soon after infection.


Asunto(s)
Carcinoma in Situ/virología , Inhibición de Contacto , Papillomavirus Humano 16/patogenicidad , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Represoras/metabolismo , Neoplasias del Cuello Uterino/virología , Factores de Virulencia/metabolismo , Células Cultivadas , Femenino , Humanos , Técnicas In Vitro
7.
Laryngoscope ; 116(8): 1434-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16885749

RESUMEN

OBJECTIVES: Minichromosome maintenance protein 2 (Mcm-2) is essential for DNA replication and serves as a useful biomarker of cell-cycle state in human tissue samples. Ki-67 is an established proliferation marker. Because Mcm-2 expression has not previously been assessed in thyroid tissue, the aim of this study was to assess the expression of both proteins in a range of thyroid lesions to determine their potential value as preoperative markers of thyroid malignancy. METHODS: Mcm-2 and Ki-67 protein expression were assessed by immunohistochemistry in formalin-fixed, paraffin-embedded thyroid tissues from 128 patients with histologic diagnoses of papillary carcinoma (n = 38), follicular carcinoma (n = 22), follicular adenoma (n = 33), and dominant nodules of multinodular goitre (n = 35). RESULTS: Mcm-2 and Ki-67-labeling indices (LIs) were both higher in follicular and papillary carcinomas than in follicular adenomas or dominant nodules. The Ki-67 LI discriminated better between follicular carcinomas and follicular adenomas (P < .0001) than Mcm-2 (P = .0273). However, the Mcm-2 and Ki-67 LIs overlapped widely between the four histologic groups, and the expression of these proteins was also noted to be heterogenous within these lesions. CONCLUSION: Neither Mcm-2 or Ki-67 can currently be reliably applied as preoperative markers to distinguish benign from malignant thyroid lesions.


Asunto(s)
Biomarcadores de Tumor/análisis , Proteínas de Ciclo Celular/análisis , Antígeno Ki-67/análisis , Proteínas Nucleares/análisis , Neoplasias de la Tiroides/diagnóstico , Adenoma/diagnóstico , Carcinoma Papilar/diagnóstico , Bocio Nodular/diagnóstico , Humanos , Inmunohistoquímica , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Glándula Tiroides/química
8.
Horm Res ; 65(4): 200-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16567946

RESUMEN

BACKGROUND: Wolffian ducts (WDs) are the embryonic precursors of the male reproductive tract. Their development is induced by testosterone, which interacts with the androgen receptor (AR). The molecular pathways underlying androgen-dependent WD development are largely unknown. We aimed to identify AR target genes important in this process. METHODS: RNA was isolated from rat WDs at E17.5 and E20.5. Affymetrix GeneChip expression arrays were used to identify transcripts up- or downregulated more than 2-fold. Regulation of seven transcripts was confirmed using quantitative PCR. RESULTS: Transcripts from 76 known genes were regulated, including modulators of insulin-like growth factor and transforming growth factor-beta signalling. By controlling these modulators, androgens may indirectly affect growth factor signalling pathways important in epithelial-mesenchymal interactions and organ development. Caveolin-1, also upregulated, may play a role in modifying as well as mediating AR signalling. Differentiation of WD epithelium and smooth muscle, innervation and extracellular matrix synthesis were reflected in regulation of other transcripts. Several genes were previously suggested to be regulated by androgens or contained functional or putative androgen/glucocorticoid response elements, indicating they may be direct targets of androgen signalling. CONCLUSION: Our results suggest novel cohorts of signals that may contribute to androgen-dependent WD development and provide hypotheses that can be tested by future studies.


Asunto(s)
Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Receptores Androgénicos/fisiología , Conductos Mesonéfricos/crecimiento & desarrollo , Conductos Mesonéfricos/fisiología , Andrógenos/fisiología , Animales , Caveolina 1/genética , Caveolina 1/fisiología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Cistatinas , ADN/análisis , ADN/genética , Femenino , Masculino , Músculo Liso/citología , Músculo Liso/crecimiento & desarrollo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reacción en Cadena de la Polimerasa , Proteínas/genética , Proteínas/fisiología , ARN/análisis , Ratas , Ratas Wistar , Receptores Androgénicos/genética , Elementos de Respuesta/genética , Elementos de Respuesta/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiología , Somatomedinas/genética , Somatomedinas/fisiología , Testosterona/fisiología , Transcripción Genética , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/fisiología , Conductos Mesonéfricos/química , Conductos Mesonéfricos/citología
9.
J Clin Endocrinol Metab ; 89(11): 5815-22, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15531547

RESUMEN

Development of the Wolffian ducts (WD) into epididymides and vasa deferentia is dependent on testosterone. Patients with the complete androgen insensitivity syndrome (CAIS) are therefore not expected to develop these structures. However, WD derivatives have been described in cases of CAIS. It is thought that these may be remnants. This study assesses the degree of WD development in 33 patients with CAIS and investigates whether this development was androgen dependent. Epididymides and vasa deferentia were identified in 70% of patients with substitution mutations in the androgen receptor ligand-binding domain. They were more developed than epididymides and vasa deferentia from 16- to 20-wk-old male fetuses, suggesting that the WD had been stimulated to grow, rather than failed to regress. Receptors with substitutions in the ligand-binding domain were normally expressed and showed residual response to androgens in transactivation assays. Patients with premature stop codons or frameshift mutations, which prevented androgen receptor expression, or DNA-binding domain mutations that abolished transcriptional activity did not have epididymides or vasa deferentia. We hypothesize that mutant receptors with residual activity in vitro respond to high local testosterone concentrations in vivo, thereby stimulating WD development. The classification of androgen insensitivity in such patients should be considered severe rather than complete.


Asunto(s)
Síndrome de Resistencia Androgénica/fisiopatología , Mutación , Receptores Androgénicos/genética , Conductos Mesonéfricos/crecimiento & desarrollo , Adolescente , Adulto , Animales , Sitios de Unión , Células COS , Niño , Preescolar , ADN/metabolismo , Femenino , Humanos , Lactante , Masculino , Estructura Secundaria de Proteína , Receptores Androgénicos/química , Receptores Androgénicos/fisiología
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