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1.
PLoS Biol ; 21(12): e3002397, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38051702

RESUMEN

Since they emerged approximately 125 million years ago, flowering plants have evolved to dominate the terrestrial landscape and survive in the most inhospitable environments on earth. At their core, these adaptations have been shaped by changes in numerous, interconnected pathways and genes that collectively give rise to emergent biological phenomena. Linking gene expression to morphological outcomes remains a grand challenge in biology, and new approaches are needed to begin to address this gap. Here, we implemented topological data analysis (TDA) to summarize the high dimensionality and noisiness of gene expression data using lens functions that delineate plant tissue and stress responses. Using this framework, we created a topological representation of the shape of gene expression across plant evolution, development, and environment for the phylogenetically diverse flowering plants. The TDA-based Mapper graphs form a well-defined gradient of tissues from leaves to seeds, or from healthy to stressed samples, depending on the lens function. This suggests that there are distinct and conserved expression patterns across angiosperms that delineate different tissue types or responses to biotic and abiotic stresses. Genes that correlate with the tissue lens function are enriched in central processes such as photosynthetic, growth and development, housekeeping, or stress responses. Together, our results highlight the power of TDA for analyzing complex biological data and reveal a core expression backbone that defines plant form and function.


Asunto(s)
Magnoliopsida , Magnoliopsida/genética , Plantas/genética , Estrés Fisiológico/genética , Hojas de la Planta/genética , Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética
2.
PLoS Biol ; 16(9): e2005046, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30180168

RESUMEN

The microenvironment of lymphoid organs can aid healthy immune function through provision of both structural and molecular support. In mice, fibroblastic reticular cells (FRCs) create an essential T-cell support structure within lymph nodes, while human FRCs are largely unstudied. Here, we show that FRCs create a regulatory checkpoint in human peripheral T-cell activation through 4 mechanisms simultaneously utilised. Human tonsil and lymph node-derived FRCs constrained the proliferation of both naïve and pre-activated T cells, skewing their differentiation away from a central memory T-cell phenotype. FRCs acted unilaterally without requiring T-cell feedback, imposing suppression via indoleamine-2,3-dioxygenase, adenosine 2A Receptor, prostaglandin E2, and transforming growth factor beta receptor (TGFßR). Each mechanistic pathway was druggable, and a cocktail of inhibitors, targeting all 4 mechanisms, entirely reversed the suppressive effect of FRCs. T cells were not permanently anergised by FRCs, and studies using chimeric antigen receptor (CAR) T cells showed that immunotherapeutic T cells retained effector functions in the presence of FRCs. Since mice were not suitable as a proof-of-concept model, we instead developed a novel human tissue-based in situ assay. Human T cells stimulated using standard methods within fresh tonsil slices did not proliferate except in the presence of inhibitors described above. Collectively, we define a 4-part molecular mechanism by which FRCs regulate the T-cell response to strongly activating events in secondary lymphoid organs while permitting activated and CAR T cells to utilise effector functions. Our results define 4 feasible strategies, used alone or in combinations, to boost primary T-cell responses to infection or cancer by pharmacologically targeting FRCs.


Asunto(s)
Diferenciación Celular/inmunología , Microambiente Celular , Ganglios Linfáticos/inmunología , Activación de Linfocitos/inmunología , Linfocitos T/citología , Adulto , Proliferación Celular , Niño , Fibroblastos/citología , Humanos , Memoria Inmunológica , Fenotipo
3.
J Immunol ; 203(5): 1151-1159, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31391236

RESUMEN

There is no effective treatment for autoimmune biliary diseases. Therefore, understanding their immunopathology is crucial. The biliary epithelial cells (BEC), expressing TLR-4, are constantly exposed to gut microbes and bacterial wall LPS, and in settings of inflammation, the immune infiltrate is dense within the peribiliary region of human liver. By dual immunohistochemistry, we affirm human intrahepatic T cell infiltrate includes CCR6+CD4+ and AhR+CD4+ T cells with potential for plasticity to Th17 phenotype. Mechanistically, we demonstrate that Th1 and Th17 inflammatory cytokines and LPS enhance human primary BEC release of the CCR6 ligand CCL20 and BEC secretion of Th17-polarizing cytokines IL-6 and IL-1ß. Cell culture assays with human BEC secretome showed that secretome polarizes CD4 T cells toward a Th17 phenotype and supports the survival of Th17 cells. BEC secretome did not promote Th1 cell generation. Additionally, we give evidence for a mutually beneficial feedback of the type 17 cell infiltrate on BEC, showing that treatment with type 17 cytokines increases BEC proliferation, as monitored by Ki67 and activation of JAK2-STAT3 signaling. This study identifies human BEC as active players in determining the nature of the intrahepatic immune microenvironment. In settings of inflammation and/or infection, biliary epithelium establishes a prominent peribiliary type 17 infiltrate via recruitment and retention and enhances polarization of intrahepatic CD4 cells toward Th17 cells via type 17 cytokines, and, reciprocally, Th17 cells promote BEC proliferation for biliary regeneration. Altogether, we provide new insight into cross-talk between Th17 lymphocytes and human primary biliary epithelium in biliary regenerative pathologies.


Asunto(s)
Conductos Biliares/patología , Comunicación Celular/fisiología , Células Epiteliales/fisiología , Hepatopatías/inmunología , Células Th17/fisiología , Proliferación Celular , Células Cultivadas , Humanos , Interleucina-17/farmacología , Lipopolisacáridos/farmacología , Hepatopatías/patología , Receptores de Hidrocarburo de Aril/fisiología , Receptores CCR6/fisiología
4.
Cochrane Database Syst Rev ; 6: CD012602, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34061352

RESUMEN

BACKGROUND: Miscarriage, defined as the spontaneous loss of a pregnancy before 24 weeks' gestation, is common with approximately 25% of women experiencing a miscarriage in their lifetime. An estimated 15% of pregnancies end in miscarriage. Miscarriage can lead to serious morbidity, including haemorrhage, infection, and even death, particularly in settings without adequate healthcare provision. Early miscarriages occur during the first 14 weeks of pregnancy, and can be managed expectantly, medically or surgically. However, there is uncertainty about the relative effectiveness and risks of each option. OBJECTIVES: To estimate the relative effectiveness and safety profiles for the different management methods for early miscarriage, and to provide rankings of the available methods according to their effectiveness, safety, and side-effect profile using a network meta-analysis. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth's Trials Register (9 February 2021), ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (12 February 2021), and reference lists of retrieved studies. SELECTION CRITERIA: We included all randomised controlled trials assessing the effectiveness or safety of methods for miscarriage management. Early miscarriage was defined as less than or equal to 14 weeks of gestation, and included missed and incomplete miscarriage. Management of late miscarriages after 14 weeks of gestation (often referred to as intrauterine fetal deaths) was not eligible for inclusion in the review. Cluster- and quasi-randomised trials were eligible for inclusion. Randomised trials published only as abstracts were eligible if sufficient information could be retrieved. We excluded non-randomised trials. DATA COLLECTION AND ANALYSIS: At least three review authors independently assessed the trials for inclusion and risk of bias, extracted data and checked them for accuracy. We estimated the relative effects and rankings for the primary outcomes of complete miscarriage and composite outcome of death or serious complications. The certainty of evidence was assessed using GRADE. Relative effects for the primary outcomes are reported subgrouped by the type of miscarriage (incomplete and missed miscarriage). We also performed pairwise meta-analyses and network meta-analysis to determine the relative effects and rankings of all available methods. MAIN RESULTS: Our network meta-analysis included 78 randomised trials involving 17,795 women from 37 countries. Most trials (71/78) were conducted in hospital settings and included women with missed or incomplete miscarriage. Across 158 trial arms, the following methods were used: 51 trial arms (33%) used misoprostol; 50 (32%) used suction aspiration; 26 (16%) used expectant management or placebo; 17 (11%) used dilatation and curettage; 11 (6%) used mifepristone plus misoprostol; and three (2%) used suction aspiration plus cervical preparation. Of these 78 studies, 71 (90%) contributed data in a usable form for meta-analysis. Complete miscarriage Based on the relative effects from the network meta-analysis of 59 trials (12,591 women), we found that five methods may be more effective than expectant management or placebo for achieving a complete miscarriage: · suction aspiration after cervical preparation (risk ratio (RR) 2.12, 95% confidence interval (CI) 1.41 to 3.20, low-certainty evidence), · dilatation and curettage (RR 1.49, 95% CI 1.26 to 1.75, low-certainty evidence), · suction aspiration (RR 1.44, 95% CI 1.29 to 1.62, low-certainty evidence), · mifepristone plus misoprostol (RR 1.42, 95% CI 1.22 to 1.66, moderate-certainty evidence), · misoprostol (RR 1.30, 95% CI 1.16 to 1.46, low-certainty evidence). The highest ranked surgical method was suction aspiration after cervical preparation. The highest ranked non-surgical treatment was mifepristone plus misoprostol. All surgical methods were ranked higher than medical methods, which in turn ranked above expectant management or placebo. Composite outcome of death and serious complications Based on the relative effects from the network meta-analysis of 35 trials (8161 women), we found that four methods with available data were compatible with a wide range of treatment effects compared with expectant management or placebo: · dilatation and curettage (RR 0.43, 95% CI 0.17 to 1.06, low-certainty evidence), · suction aspiration (RR 0.55, 95% CI 0.23 to 1.32, low-certainty evidence), · misoprostol (RR 0.50, 95% CI 0.22 to 1.15, low-certainty evidence), · mifepristone plus misoprostol (RR 0.76, 95% CI 0.31 to 1.84, low-certainty evidence). Importantly, no deaths were reported in these studies, thus this composite outcome was entirely composed of serious complications, including blood transfusions, uterine perforations, hysterectomies, and intensive care unit admissions. Expectant management and placebo ranked the lowest when compared with alternative treatment interventions. Subgroup analyses by type of miscarriage (missed or incomplete) agreed with the overall analysis in that surgical methods were the most effective treatment, followed by medical methods and then expectant management or placebo, but there are possible subgroup differences in the effectiveness of the available methods.  AUTHORS' CONCLUSIONS: Based on relative effects from the network meta-analysis, all surgical and medical methods for managing a miscarriage may be more effective than expectant management or placebo. Surgical methods were ranked highest for managing a miscarriage, followed by medical methods, which in turn ranked above expectant management or placebo. Expectant management or placebo had the highest chance of serious complications, including the need for unplanned or emergency surgery. A subgroup analysis showed that surgical and medical methods may be more beneficial in women with missed miscarriage compared to women with incomplete miscarriage. Since type of miscarriage (missed and incomplete) appears to be a source of inconsistency and heterogeneity within these data, we acknowledge that the main network meta-analysis may be unreliable. However, we plan to explore this further in future updates and consider the primary analysis as separate networks for missed and incomplete miscarriage.


Asunto(s)
Aborto Espontáneo/terapia , Primer Trimestre del Embarazo , Aborto Incompleto/terapia , Aborto Retenido/terapia , Quimioterapia Combinada , Femenino , Humanos , Mifepristona/administración & dosificación , Misoprostol/administración & dosificación , Metaanálisis en Red , Oxitócicos/administración & dosificación , Placebos/administración & dosificación , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Succión/estadística & datos numéricos , Legrado por Aspiración/estadística & datos numéricos , Espera Vigilante/estadística & datos numéricos
5.
Gut ; 67(5): 918-930, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29097439

RESUMEN

BACKGROUND/AIMS: Intestinal permeability with systemic distribution of bacterial products are central in the immunopathogenesis of alcoholic liver disease (ALD), yet links with intestinal immunity remain elusive. Mucosa-associated invariant T cells (MAIT) are found in liver, blood and intestinal mucosa and are a key component of antibacterial host defences. Their role in ALD is unknown. METHODS/DESIGN: We analysed frequency, phenotype, transcriptional regulation and function of blood MAIT cells in severe alcoholic hepatitis (SAH), alcohol-related cirrhosis (ARC) and healthy controls (HC). We also examined direct impact of ethanol, bacterial products from faecal extracts and antigenic hyperstimulation on MAIT cell functionality. Presence of MAIT cells in colon and liver was assessed by quantitative PCR and immunohistochemistry/gene expression respectively. RESULTS: In ARC and SAH, blood MAIT cells were dramatically depleted, hyperactivated and displayed defective antibacterial cytokine/cytotoxic responses. These correlated with suppression of lineage-specific transcription factors and hyperexpression of homing receptors in the liver with intrahepatic preservation of MAIT cells in ALD. These alterations were stronger in SAH, where surrogate markers of bacterial infection and microbial translocation were higher than ARC. Ethanol exposure in vitro, in vivo alcohol withdrawal and treatment with Escherichia coli had no effect on MAIT cell frequencies, whereas exposure to faecal bacteria/antigens induced functional impairments comparable with blood MAIT cells from ALD and significant MAIT cell depletion, which was not observed in other T cell compartments. CONCLUSIONS: In ALD, the antibacterial potency of MAIT cells is compromised as a consequence of contact with microbial products and microbiota, suggesting that the 'leaky' gut observed in ALD drives MAIT cell dysfunction and susceptibility to infection in these patients.


Asunto(s)
Etanol/efectos adversos , Mucosa Intestinal/inmunología , Hepatopatías Alcohólicas/inmunología , Células T Invariantes Asociadas a Mucosa/metabolismo , Adulto , Técnicas de Cultivo de Célula , Citocinas/metabolismo , Heces/microbiología , Femenino , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Mucosa Intestinal/microbiología , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/microbiología , Masculino , Persona de Mediana Edad , Células T Invariantes Asociadas a Mucosa/inmunología , Células T Invariantes Asociadas a Mucosa/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa
6.
J Hepatol ; 69(3): 654-665, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29758330

RESUMEN

BACKGROUND & AIMS: γδ T cells comprise a substantial proportion of tissue-associated lymphocytes. However, our current understanding of human γδ T cells is primarily based on peripheral blood subsets, while the immunobiology of tissue-associated subsets remains largely unclear. Therefore, we aimed to elucidate the T cell receptor (TCR) diversity, immunophenotype and function of γδ T cells in the human liver. METHODS: We characterised the TCR repertoire, immunophenotype and function of human liver infiltrating γδ T cells, by TCR sequencing analysis, flow cytometry, in situ hybridisation and immunohistochemistry. We focussed on the predominant tissue-associated Vδ2- γδ subset, which is implicated in liver immunopathology. RESULTS: Intrahepatic Vδ2- γδ T cells were highly clonally focussed, with single expanded clonotypes featuring complex, private TCR rearrangements frequently dominating the compartment. Such T cells were predominantly CD27lo/- effector lymphocytes, whereas naïve CD27hi, TCR-diverse populations present in matched blood were generally absent in the liver. Furthermore, while a CD45RAhi Vδ2- γδ effector subset present in both liver and peripheral blood contained overlapping TCR clonotypes, the liver Vδ2- γδ T cell pool also included a phenotypically distinct CD45RAlo effector compartment that was enriched for expression of the tissue tropism marker CD69, the hepatic homing chemokine receptors CXCR3 and CXCR6, and liver-restricted TCR clonotypes, suggestive of intrahepatic tissue residency. Liver infiltrating Vδ2- γδ cells were capable of polyfunctional cytokine secretion, and unlike peripheral blood subsets, were responsive to both TCR and innate stimuli. CONCLUSION: These findings suggest that the ability of Vδ2- γδ T cells to undergo clonotypic expansion and differentiation is crucial in permitting access to solid tissues, such as the liver, which results in functionally distinct peripheral and liver-resident memory γδ T cell subsets. They also highlight the inherent functional plasticity within the Vδ2- γδ T cell compartment and provide information that could be used for the design of cellular therapies that suppress liver inflammation or combat liver cancer. LAY SUMMARY: γδ T cells are frequently enriched in many solid tissues, however the immunobiology of such tissue-associated subsets in humans has remained unclear. We show that intrahepatic γδ T cells are enriched for clonally expanded effector T cells, whereas naïve γδ T cells are largely excluded. Moreover, whereas a distinct proportion of circulating T cell clonotypes was present in both the liver tissue and peripheral blood, a functionally and clonotypically distinct population of liver-resident γδ T cells was also evident. Our findings suggest that factors triggering γδ T cell clonal selection and differentiation, such as infection, can drive enrichment of γδ T cells into liver tissue, allowing the development of functionally distinct tissue-restricted memory populations specialised in local hepatic immunosurveillance.


Asunto(s)
Memoria Inmunológica/fisiología , Linfocitos Intraepiteliales , Hígado , Subgrupos de Linfocitos T/inmunología , Diferenciación Celular/inmunología , Células Cultivadas , Humanos , Linfocitos Intraepiteliales/inmunología , Linfocitos Intraepiteliales/patología , Hígado/inmunología , Hígado/patología , Monitorización Inmunológica/métodos , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología
7.
Hepatology ; 64(1): 138-50, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26928938

RESUMEN

UNLABELLED: Regulatory T cells (Treg ) suppress T effector cell proliferation and maintain immune homeostasis. Autoimmune liver diseases persist despite high frequencies of Treg in the liver, suggesting that the local hepatic microenvironment might affect Treg stability, survival, and function. We hypothesized that interactions between Treg and endothelial cells during recruitment and then with epithelial cells within the liver affect Treg stability, survival, and function. To model this, we explored the function of Treg after migration through human hepatic sinusoidal-endothelium (postendothelial migrated Treg [PEM Treg ]) and the effect of subsequent interactions with cholangiocytes and local proinflammatory cytokines on survival and stability of Treg . Our findings suggest that the intrahepatic microenvironment is highly enriched with proinflammatory cytokines but deficient in the Treg survival cytokine interleukin (IL)-2. Migration through endothelium into a model mimicking the inflamed liver microenvironment did not affect Treg stability; however, functional capacity was reduced. Furthermore, the addition of exogenous IL-2 enhanced PEM Treg phosphorylated STAT5 signaling compared with PEMCD8. CD4 and CD8 T cells are the main source of IL-2 in the inflamed liver. Liver-infiltrating Treg reside close to bile ducts and coculture with cholangiocytes or their supernatants induced preferential apoptosis of Treg compared with CD8 effector cells. Treg from diseased livers expressed high levels of CD95, and their apoptosis was inhibited by IL-2 or blockade of CD95. CONCLUSION: Recruitment through endothelium does not impair Treg stability, but a proinflammatory microenvironment deficient in IL-2 leads to impaired function and increased susceptibility of Treg to epithelial cell-induced Fas-mediated apoptosis. These results provide a mechanism to explain Treg dysfunction in inflamed tissues and suggest that IL-2 supplementation, particularly if used in conjunction with Treg therapy, could restore immune homeostasis in inflammatory and autoimmune liver disease. (Hepatology 2016;64:138-150).


Asunto(s)
Interleucina-2/metabolismo , Hepatopatías/inmunología , Linfocitos T Reguladores/fisiología , Apoptosis , Antígenos CD8/metabolismo , Microambiente Celular , Endotelio/fisiología , Proteína Ligando Fas/metabolismo , Humanos , Factor de Transcripción STAT5/metabolismo , Receptor fas/metabolismo
8.
J Hepatol ; 64(5): 1118-1127, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26743076

RESUMEN

BACKGROUND & AIMS: Mucosal-Associated Invariant T (MAIT) cells are innate-like T cells characterised by the invariant TCR-chain, Vα7.2-Jα33, and are restricted by MR1, which presents bacterial vitamin B metabolites. They are important for antibacterial immunity at mucosal sites; however, detailed characteristics of liver-infiltrating MAIT (LI-MAIT) and their role in biliary immune surveillance remain unexplored. METHODS: The phenotype and intrahepatic localisation of human LI-MAIT cells was examined in diseased and normal livers. MAIT cell activation in response to E. coli-exposed macrophages, biliary epithelial cells (BEC) and liver B cells was assessed with/without anti-MR1. RESULTS: Intrahepatic MAIT cells predominantly localised to bile ducts in the portal tracts. Consistent with this distribution, they expressed biliary tropic chemokine receptors CCR6, CXCR6, and integrin αEß7. LI-MAIT cells were also present in the hepatic sinusoids and possessed tissue-homing chemokine receptor CXCR3 and integrins LFA-1 and VLA-4, suggesting their recruitment via hepatic sinusoids. LI-MAIT cells were enriched in the parenchyma of acute liver failure livers compared to chronic diseased livers. LI-MAIT cells had an activated, effector memory phenotype, expressed α4ß7 and receptors for IL-12, IL-18, and IL-23. Importantly, in response to E. coli-exposed macrophages, liver B cells and BEC, MAIT cells upregulated IFN-γ and CD40 Ligand and degranulated in an MR1-dependent, cytokine-independent manner. In addition, diseased liver MAIT cells expressed T-bet and RORγt and the cytokines IFN-γ, TNF-α, and IL-17. CONCLUSIONS: Our findings provide the first evidence of an immune surveillance effector response for MAIT cells towards BEC in human liver; thus they could be manipulated for treatment of biliary disease in the future.


Asunto(s)
Linfocitos B/inmunología , Conductos Biliares Intrahepáticos/patología , Inmunidad Innata , Hígado/inmunología , Activación de Linfocitos/inmunología , Células T Invariantes Asociadas a Mucosa/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos B/patología , Conductos Biliares Intrahepáticos/inmunología , Conductos Biliares Intrahepáticos/metabolismo , Escherichia coli , Humanos , Hígado/metabolismo , Hígado/patología
9.
Pediatr Nephrol ; 36(2): 319-320, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32556541
10.
Pediatr Nephrol ; 36(2): 321-322, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32556542
11.
J Gen Virol ; 96(12): 3598-3612, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26416316

RESUMEN

Human cytomegalovirus (hCMV) is a beta herpesvirus that establishes lifelong infection. Although the virus does not usually cause overt clinical symptoms in immunocompetent individuals it can have deleterious effects in immunocompromised patients, such as those on post-transplant medication or with HIV infection. hCMV is the most common congenital infection and can lead to serious fetal sequelae. Endothelial cells (ECs) are natural hosts for hCMV in vivo, therefore, investigations of how this cell type is modulated by infection are key to understanding hCMV pathogenesis. Previous studies have examined the effect of secretomes from hCMV-infected cells on EC angiogenesis, whereas the effect of direct infection on this process has not been so well investigated. Here, we show that placental ECs are viral targets during congenital infection and that vessels in infected tissue appear morphologically abnormal. We demonstrate that the clinical hCMV strain VR1814 impaired EC tube assembly in in vitro angiogenesis assays and inhibited wound healing ability in scratch assays. Secretomes from infected cultures did not impair angiogenesis of uninfected ECs, suggesting that cell-intrinsic changes, as opposed to secreted factors, were responsible. We observed viral gene transcription dependent downregulation of the expression of angiogenesis-associated genes, including angiopoietin-2, TEK receptor and vascular endothelial growth factor receptors. An alternative clinical hCMV stain, TB40E showed similar effects on EC angiogenesis. Together, our data indicate that direct infection with hCMV can induce an anti-migratory and anti-angiogenic EC phenotype, which could have a detrimental effect on the vasculature development in infected tissues.


Asunto(s)
Movimiento Celular , Infecciones por Citomegalovirus/congénito , Citomegalovirus/fisiología , Células Endoteliales/fisiología , Células Endoteliales/virología , Neovascularización Fisiológica , Células Cultivadas , Infecciones por Citomegalovirus/virología , Femenino , Regulación Viral de la Expresión Génica , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Interleucina-10/genética , Interleucina-10/metabolismo , Placenta/irrigación sanguínea , Placenta/citología , Placenta/virología , Embarazo , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
BMC Public Health ; 15: 1258, 2015 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-26686997

RESUMEN

BACKGROUND: Given the intimate association between silicosis and tuberculosis, understanding the epidemiology of the South African gold mining industry silicosis epidemic is essential to current initiatives to control both silicosis and tuberculosis in this population, one of the most heavily affected globally. The study's objectives were to compare the prevalence of silicosis among working black gold miners in South Africa during 2004-2009 to that of previous studies, including autopsy series, and to analyse the influence of silicosis and/or tuberculosis on exiting employment. METHODS: Routine chest radiographs from a cohort of gold miners were read for silicosis by an experienced reader (I), and a subset re-read by a B-trained reader (II). Two methods of presenting the readings were used. Additionally, with baseline status of silicosis and previous or active tuberculosis as predictors, survival analysis examined the probability of exiting the workforce for any reason during 2006-2011. RESULTS: Reader I read 11 557 chest radiographs and reader II re-read 841. Overall, silicosis prevalence (ILO ≥ 1/0: 5.7 and 6.2% depending on reader method) was similar to the age adjusted prevalence found in a large study in 1984 (5.0%). When comparison was restricted to a single mine shaft previously studied in 2000, a decline in prevalence (ILO ≥ 1/1) was suggested for one of the reading methods (duration adjusted 20.5% vs. 13.0% in the current study). These findings are discordant with a long-term rising autopsy prevalence of silicosis over this period. Overall, relative to miners with neither disease, the adjusted hazard ratio for exiting employment during the follow-up period was 1.54 for baseline silicosis [95% confidence interval (CI) 1.17, 2.04], 1.71 for tuberculosis (95% CI 1.51, 1.94) and 1.53 for combined disease (95% CI 1.20, 1.96). CONCLUSIONS: This study found, a) there was no significant decline in overall silicosis prevalence among working black miners in the South African gold mining industry between 1984 and 2004-2009, and b) a possible decline at one mine shaft more recently. In the absence of evidence of declining respirable silica concentrations between the 1980s and 2000s, the trends found are plausibly due to a healthy worker survivor effect, which may be accelerating.


Asunto(s)
Efecto del Trabajador Sano , Mineros/estadística & datos numéricos , Minería/estadística & datos numéricos , Enfermedades Profesionales/epidemiología , Silicosis/epidemiología , Tuberculosis Pulmonar/epidemiología , Adulto , Estudios Transversales , Empleo , Estudios de Seguimiento , Oro , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/diagnóstico , Exposición Profesional/estadística & datos numéricos , Prevalencia , Silicosis/diagnóstico , Sudáfrica/epidemiología , Análisis de Supervivencia , Tuberculosis Pulmonar/diagnóstico
13.
J Am Soc Nephrol ; 25(8): 1669-78, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24722450

RESUMEN

Anemia is a feature of CKD and a complication of renal transplantation, often caused by impaired production of erythropoietin. The kidney is a target organ for human cytomegalovirus (hCMV) in such patients, but it is not known whether hCMV effects erythropoietin production. We found that kidneys from patients with CKD were positive for hCMV protein and that blood levels of hCMV IgG inversely correlated with red blood cell count. In mice, systemic murine cytomegalovirus infection decreased serum erythropoietin levels. In human erythropoietin-producing cells, hCMV inhibited hypoxia-induced expression of erythropoietin mRNA and protein. hCMV early gene expression was responsible, as ultraviolet-inactivated virus had no effect and valganciclovir treatment showed that late gene expression was nonessential. Hypoxia-induced gene transcription is controlled by the transcription factors hypoxia-inducible transcription factor (HIF)-1α and HIF2α, which are constitutively produced but stable only under low oxygen conditions. We found that hCMV inhibited constitutive production of HIF2α mRNA. HIF2α is thought to be the master regulator of erythropoietin transcription. Single-cell analysis revealed that nuclear accumulation of HIF2α was inhibited in hCMV-infected cells, and the extent of inhibition correlated with hCMV protein expression. Our findings suggest that renal hCMV infection could induce or exacerbate anemia in patients.


Asunto(s)
Citomegalovirus/fisiología , Eritropoyetina/metabolismo , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/virología , Animales , Anticuerpos Antivirales/sangre , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Técnicas de Cultivo de Célula , Hipoxia de la Célula , Recuento de Eritrocitos , Eritropoyetina/genética , Hemoglobinas/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunoglobulina G/metabolismo , Ratones , ARN Mensajero/metabolismo , Insuficiencia Renal Crónica/patología
14.
PLoS One ; 18(10): e0292343, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37815986

RESUMEN

Communities of practice (CoPs) are defined as "groups of people who share a concern, a set of problems, or a passion about a topic, and who deepen their knowledge and expertise by interacting on an ongoing basis". They are an effective form of knowledge management that have been successfully used in the business sector and increasingly so in healthcare. In May 2023 the electronic databases MEDLINE and EMBASE were systematically searched for primary research studies on CoPs published between 1st January 1950 and 31st December 2022. PRISMA guidelines were followed. The following search terms were used: community/communities of practice AND (healthcare OR medicine OR patient/s). The database search picked up 2009 studies for screening. Of these, 50 papers met the inclusion criteria. The most common aim of CoPs was to directly improve a clinical outcome, with 19 studies aiming to achieve this. In terms of outcomes, qualitative outcomes were the most common measure used in 21 studies. Only 11 of the studies with a quantitative element had the appropriate statistical methodology to report significance. Of the 9 studies that showed a statistically significant effect, 5 showed improvements in hospital-based provision of services such as discharge planning or rehabilitation services. 2 of the studies showed improvements in primary-care, such as management of hepatitis C, and 2 studies showed improvements in direct clinical outcomes, such as central line infections. CoPs in healthcare are aimed at improving clinical outcomes and have been shown to be effective. There is still progress to be made and a need for further studies with more rigorous methodologies, such as RCTs, to provide further support of the causality of CoPs on outcomes.


Asunto(s)
Hospitales , Alta del Paciente , Humanos , Atención a la Salud
15.
Plant Genome ; 16(3): e20364, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37415293

RESUMEN

Dry beans (Phaseolus vulgaris L.) are a nutritious food, but their lengthy cooking requirements are barriers to consumption. Presoaking is one strategy to reduce cooking time. Soaking allows hydration to occur prior to cooking, and enzymatic changes to pectic polysaccharides also occur during soaking that shorten the cooking time of beans. Little is known about how gene expression during soaking influences cooking times. The objectives of this study were to (1) identify gene expression patterns that are altered by soaking and (2) compare gene expression in fast-cooking and slow-cooking bean genotypes. RNA was extracted from four bean genotypes at five soaking time points (0, 3, 6, 12, and 18 h) and expression abundances were detected using Quant-seq. Differential gene expression analysis and weighted gene coexpression network analysis were used to identify candidate genes within quantitative trait loci for water uptake and cooking time. Genes related to cell wall growth and development as well as hypoxic stress were differentially expressed between the fast- and slow-cooking beans due to soaking. Candidate genes identified in the slow-cooking beans included enzymes that increase intracellular calcium concentrations and cell wall modification enzymes. The expression of cell wall-strengthening enzymes in the slow-cooking beans may increase their cooking time and ability to resist osmotic stress by preventing cell separation and water uptake in the cotyledon.


Asunto(s)
Phaseolus , Phaseolus/genética , Culinaria , Perfilación de la Expresión Génica , Agua , Pared Celular
16.
Exp Cell Res ; 317(3): 276-92, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21056557

RESUMEN

We investigated the migration of human leukocytes through endothelial cells (EC), and particularly their underlying basement membrane (BM). EC were cultured for 20days on 3µm-pore filters or collagen gels to form a distinct BM, and then treated with tumour necrosis factor-α, interleukin-1ß or interferon-γ. Neutrophil migration through the cytokine-treated EC and BM was delayed for 20-day compared to 4-day cultures. The BM alone obstructed chemotaxis of neutrophils, and if fresh EC were briefly cultured on stripped BM, there was again a hold-up in migration. In studies with lymphocytes and monocytes, we could detect little hold-up of migration for 20-day versus 4-day cultures, in either the filter- or gel-based models. Direct microscopic observations showed that BM also held-up neutrophil migration under conditions of flow. Treatment of upper and/or lower compartments of filters with antibodies against integrins, showed that neutrophil migration through the endothelial monolayer was dependent on ß(2)-integrins, but not ß1- or ß(3)-integrins. Migration from the subendothelial compartment was supported by ß1- and ß(2)-integrins for all cultures, but blockade of ß(3)-integrin only inhibited migration effectively for 20-day cultures. Flow cytometry indicated that there was no net increase in expression of ß1- or ß3-integrins during neutrophil migration, and that their specific subendothelial function was likely dependent on turnover of integrins during migration. These studies show that BM is a distinct barrier to migration of human neutrophils, and that ß(3)-integrins are particularly important in crossing this barrier. The lesser effect of BM on lymphocytes and monocytes supports the concept that crossing the BM is a separate, leukocyte-specific, regulated step in migration.


Asunto(s)
Membrana Basal/metabolismo , Quimiotaxis de Leucocito , Células Endoteliales/citología , Leucocitos/citología , Antígenos CD18/análisis , Técnicas de Cultivo de Célula , Células Endoteliales/ultraestructura , Humanos , Integrina beta1/análisis , Integrina beta3/análisis , Leucocitos/fisiología , Linfocitos/citología , Monocitos/citología , Neutrófilos/citología , Neutrófilos/fisiología , Tiempo
17.
Eur J Cardiovasc Prev Rehabil ; 17(1): 89-93, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19923996

RESUMEN

BACKGROUND: Earlier, a G/T single nucleotide polymorphism (SNP) in the HMGCR gene was shown to significantly reduce the overall serum lipids response to pravastatin. This study aimed to investigate the relationship of the rs17238540 SNP with coronary heart disease, stroke and cardiovascular disease risk. DESIGN: Cross-sectional study from the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort. METHODS: Genotype was determined by pyrosequencing 23,011 participants, for whom clinical and biochemical data were available. Baseline risk factors according to genotype were evaluated, and the risk for fatal and nonfatal stroke, ischaemic heart disease and all types of cardiovascular diseases were assessed by logistic regression after approximately 11 years of follow-up. RESULTS: The G allele carriers presented 1.4 mmHg higher systolic blood pressure and 0.8 mmHg higher diastolic blood pressure than those who were TT carriers. They also presented higher risk of prevalent total (odds ratio: 1.44, 95% confidence interval: 1.05-1.97, P = 0.025) and nonfatal (odds ratio: 1.56, 95% confidence interval: 1.12-2.17, P = 0.009) stroke events compared with the TT individuals in the multivariate models. CONCLUSION: An association between the rs17238540 SNP and stroke risk was observed, independent of the effect of the SNP on the blood pressure. The possible mechanisms involved, besides the effect on blood pressure, might be related to pleiotropic functions of the HMGCR, and remain to be explored.


Asunto(s)
Hidroximetilglutaril-CoA Reductasas/genética , Polimorfismo de Nucleótido Simple , Accidente Cerebrovascular/genética , Anciano , Presión Sanguínea/genética , Enfermedad Coronaria/enzimología , Enfermedad Coronaria/genética , Estudios Transversales , Inglaterra/epidemiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/enzimología , Hipertensión/genética , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/enzimología , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
18.
Br J Nutr ; 104(5): 765-72, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20540816

RESUMEN

The objective of the present study was to investigate the influence of the single nucleotide polymorphism (rs17238540) at the 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene (HMGCR) on the relationship between serum lipids and dietary fat and fibre (NSP). FFQ and pyrosequencing were used to assess cross-sectional dietary intake and HMGCR genotype in a population study with data for serum lipids available. Genotype frequencies and allele distributions for 23 011 participants were: TT 95.65 %, TG 4.29 % and GG 0.06 %; T 97.8 % and G 2.2 %. In regression analyses, the TG+GG group showed a significant positive relationship between TAG and SFA intake (+0.11 (95 % CI 0.02, 0.20) mmol TAG/l; P = 0.017; per 3 % SFA energy increase) while the TT individuals showed no change in the TAG levels related to SFA intake ( - 0.0007 (95 % CI - 0.02, 0.02) mmol TAG/l; P = 0.99). TG+GG individuals showed an inverse relationship between TAG and fibre intake higher ( - 0.14 (95 % CI - 0.22, - 0.05) mmol TAG/l than the TT group ( - 0.04 (95 % CI - 0.06, - 0.02) mmol TAG/l). In both cases the respective coefficient regressions of TAG were different between the genotype groups (Z = 2.27, P = 0.023 for SFA intake; Z = 2.19, P = 0.029 for fibre intake). Individuals carrying the G allele may show a greater response in lower TAG levels with reduced SFA intake and increased fibre intake compared with those homozygous for the T allele. The effectiveness of different dietary interventions to control serum lipids may vary according to HMGCR genotype.


Asunto(s)
Grasas de la Dieta/metabolismo , Fibras de la Dieta/farmacología , Ácidos Grasos/metabolismo , Hidroximetilglutaril-CoA Reductasas/genética , Polimorfismo de Nucleótido Simple , Triglicéridos/sangre , Anciano , Alelos , Colesterol/sangre , Estudios Transversales , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Europa (Continente) , Ácidos Grasos/administración & dosificación , Femenino , Genotipo , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Neoplasias , Estudios Prospectivos , Encuestas y Cuestionarios
19.
Front Immunol ; 10: 1838, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31440239

RESUMEN

Background and Aims: Ascites and spontaneous bacterial peritonitis (SBP) are frequent complications of liver cirrhosis. In spite of the clinical impact, knowledge about ascites as an immune cell compartment in liver disease is limited. Therefore, we analyzed NK cells in blood, ascites, and liver. Methods: Mononuclear cells from blood, ascites, and liver explants of patients with advanced liver disease were extracted by density gradient centrifugation. Phenotyping and analysis of functional responses were carried out using flow cytometry. Migratory potential was investigated with transwell chamber assays. NK cell metabolism was assessed by Seahorse technology. Results: NK cell frequency was increased in uninfected ascites compared to blood, but not to liver. Ascites NK cells were predominantly CD16positive. CD56bright ascites NK cells did not share the typical phenotype of their liver counterparts. In contrast to the inhibitory receptor NKG2A, expression of the activating receptor NKG2D was decreased on ascites and liver CD16positive NK cells. Ascites NK cells expressed higher levels of CXCR3 than blood or liver NK cells, corresponding to increased ascites levels of CXCL10. Blood NK cells migrated toward ascites. Stimulation of mononuclear cells with Escherichia coli led to downregulation of NKG2D expression and IL-12 and IL-18 mediated secretion of interferon-γ by ascites and liver, but not blood NK cells. In-vivo, ascites NK cells expressed higher levels of the activation marker CD69 and lower levels of NKG2D during SBP compared to uninfected ascites. Conclusion: Ascites NK cells display a particular phenotype and are implicated in local immune defense against translocating bacteria.


Asunto(s)
Ascitis/inmunología , Bacterias/inmunología , Infecciones Bacterianas/inmunología , Células Asesinas Naturales/inmunología , Hepatopatías/inmunología , Peritonitis/inmunología , Anciano , Ascitis/patología , Infecciones Bacterianas/patología , Traslocación Bacteriana/inmunología , Femenino , Humanos , Células Asesinas Naturales/patología , Hepatopatías/microbiología , Hepatopatías/patología , Masculino , Persona de Mediana Edad , Peritonitis/microbiología , Peritonitis/patología
20.
JHEP Rep ; 1(4): 286-296, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32039380

RESUMEN

Autoimmune hepatitis (AIH) is an immune-mediated disease with no curative treatment. Regulatory T cell (Treg) therapy is potentially curative in AIH given the critical role of Tregs in preventing autoimmunity. To work effectively, adoptively transferred Tregs must migrate to and survive within the inflamed liver. We conducted a proof-of-concept study aiming to assess the safety and liver-homing properties of good manufacturing practice (GMP)-grade autologous Tregs in patients with AIH. METHODS: Autologous polyclonal GMP-grade Tregs were isolated using leukapheresis and CliniMACS, labelled with indium tropolonate and re-infused intravenously to 4 patients with AIH. GMP-Treg homing to the liver was investigated with longitudinal gamma camera and SPECT-CT scanning. GMP-Treg immunophenotype, function and immunometabolic state were assessed during the study. RESULTS: We observed that the isolated Tregs were suppressive and expressed CXCR3, a chemokine receptor involved in recruitment into the inflamed liver, as well as Treg functional markers CD39, CTLA-4 and the transcription factor Foxp3. Serial gamma camera and SPECT-CT imaging demonstrated that 22-44% of infused Tregs homed to and were retained in the livers of patients with autoimmune hepatitis for up to 72 h. The infused cells did not localise to any off-target organs other than the spleen and bone marrow. GMP-Tregs were metabolically competent and there were no infusion reactions or high-grade adverse effects after Treg infusion. CONCLUSION: Our novel findings suggest that the liver is a good target organ for Treg cellular therapy, supporting the development of clinical trials to test efficacy in autoimmune hepatitis and other autoimmune liver diseases. LAY SUMMARY: Autoimmune liver diseases occur when the body's immune cells target their own liver cells. Regulatory T cells (Tregs) prevent autoimmunity, thus they are a potential therapy for autoimmune liver diseases. In patients with autoimmune hepatitis, Treg infusion is safe, with nearly a quarter of infused Tregs homing to the liver and suppressing tissue-damaging effector T cells. Thus, Tregs are a potentially curative immune cell therapy for early autoimmune liver diseases.

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