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1.
J Gen Virol ; 104(4)2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37043371

RESUMEN

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus, which causes epidemics of fever, joint pain and rash. There are three genotypes: West African, East/Central/South/Africa (ECSA) and Asian, with the latter two predominant globally. Genotype-specific differences in clinical presentations, virulence and immunopathology have been described. Macrophages are key cells in immune responses against CHIKV. Circulating blood monocytes enter tissue to differentiate into monocyte-derived macrophages (MDMs) in response to CHIKV infection at key replication sites such as lymphoid organs and joints. This study analyses differences in replication and induced immune mediators following infection of MDMs with Asian and ECSA CHIKV genotypes. Primary human MDMs were derived from residual blood donations. Replication of Asian (MY/06/37348) or ECSA (MY/08/065) genotype strains of CHIKV in MDMs was measured by plaque assay. Nineteen immune mediators were measured in infected cell supernatants using multiplexed immunoassay or ELISA. MY/08/065 showed significantly higher viral replication at 24 h post-infection (h p.i.) but induced significantly lower expression of proinflammatory cytokines (CCL-2, CCL-3, CCL-4, RANTES and CXCL-10) and the anti-inflammatory IL-1Ra compared to MY/06/37348. No differences were seen at later time points up to 72 h p.i. During early infection, MY/08/065 induced lower proinflammatory immune responses in MDMs. In vivo, this may lead to poorer initial control of viral infection, facilitating CHIKV replication and dissemination to other sites such as joints. This may explain the consistent past findings that the ECSA genotype is associated with greater viremia and severity of symptoms than the Asian genotype. Knowledge of CHIKV genotype-specific immunopathogenic mechanisms in human MDMs is important in understanding of clinical epidemiology, biomarkers and therapeutics in areas with co-circulation of different genotypes.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Animales , Humanos , Virus Chikungunya/genética , Inmunidad Innata , Macrófagos , Replicación Viral , Genotipo
2.
Mol Cell ; 59(1): 104-16, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26073542

RESUMEN

The response regulator CpdR couples phosphorylation events in Caulobacter crescentus with the AAA+ protease ClpXP to provide punctuated degradation of crucial substrates involved in cell cycle regulation. CpdR functions like an adaptor to alter substrate choice by ClpXP; however, it remains unclear how CpdR influences its multiple targets. Here we show that, unlike canonical ClpXP adaptors, CpdR alone does not strongly bind its substrate. Instead, CpdR binds the N-terminal domain of ClpX and prepares (primes) the unfoldase for substrate engagement. This priming creates a recruitment interface that docks multiple substrates and additional adaptor components. We show that adaptor-dependent priming of ClpX avoids concentration-dependent inhibition that limits traditional scaffolding adaptors. Phosphosignaling disrupts the adaptor-protease interaction, and mutations in CpdR that impact ClpX binding tune adaptor activity and biological function. Together, these results reveal how a single adaptor can command global changes in proteome composition through priming of a protease.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Caulobacter crescentus/genética , Ciclo Celular/genética , Endopeptidasa Clp/metabolismo , Proteolisis , Proteínas Bacterianas/metabolismo , Sitios de Unión/genética , Caulobacter crescentus/metabolismo , Puntos de Control del Ciclo Celular/genética , Fosforilación , Unión Proteica , Estructura Terciaria de Proteína
3.
Lab Invest ; 102(2): 172-184, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34782726

RESUMEN

The phenotype of glioma-initiating cells (GIC) is modulated by cell-intrinsic and cell-extrinsic factors. Phenotypic heterogeneity and plasticity of GIC is an important limitation to therapeutic approaches targeting cancer stem cells. Plasticity also presents a challenge to the identification, isolation, and propagation of purified cancer stem cells. Here we use a barcode labelling approach of GIC to generate clonal populations over a number of passages, in combination with phenotyping using the established stem cell markers CD133, CD15, CD44, and A2B5. Using two cell lines derived from isocitrate dehydrogenase (IDH)-wildtype glioblastoma, we identify a remarkable heterogeneity of the phenotypes between the cell lines. During passaging, clonal expansion manifests as the emergence of a limited number of barcoded clones and a decrease in the overall number of clones. Dual-labelled GIC are capable of forming traceable clonal populations which emerge after as few as two passages from mixed cultures and through analyses of similarity of relative proportions of 16 surface markers we were able to pinpoint the fate of such populations. By generating tumour organoids we observed a remarkable persistence of dominant clones but also a significant plasticity of stemness marker expression. Our study presents an experimental approach to simultaneously barcode and phenotype glioma-initiating cells to assess their functional properties, for example to screen newly established GIC for tumour-specific therapeutic vulnerabilities.


Asunto(s)
Antígenos CD/inmunología , Neoplasias Encefálicas/inmunología , Glioma/inmunología , Células Madre Neoplásicas/inmunología , Microambiente Tumoral/inmunología , Antígeno AC133/inmunología , Antígeno AC133/metabolismo , Antígenos CD/metabolismo , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Células Cultivadas , Células Clonales/inmunología , Células Clonales/metabolismo , Citometría de Flujo , Glioma/metabolismo , Glioma/patología , Humanos , Receptores de Hialuranos/inmunología , Receptores de Hialuranos/metabolismo , Inmunofenotipificación , Antígeno Lewis X/inmunología , Antígeno Lewis X/metabolismo , Microscopía Confocal , Células Madre Neoplásicas/clasificación , Células Madre Neoplásicas/metabolismo
4.
BMC Infect Dis ; 21(1): 644, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-34225647

RESUMEN

BACKGROUND: Available data on influenza burden across Southeast Asia are largely limited to pediatric populations, with inconsistent findings. METHODS: We conducted a multicenter, hospital-based active surveillance study of adults in Malaysia with community-acquired pneumonia (CAP), acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and acute exacerbation of asthma (AEBA), who had influenza-like illness ≤10 days before hospitalization. We estimated the rate of laboratory-confirmed influenza and associated complications over 13 months (July 2018-August 2019) and described the distribution of causative influenza strains. We evaluated predictors of laboratory-confirmed influenza and severe clinical outcomes using multivariate analysis. RESULTS: Of 1106 included patients, 114 (10.3%) were influenza-positive; most were influenza A (85.1%), with A/H1N1pdm09 being the predominant circulating strain during the study following a shift from A/H3N2 from January-February 2019 onwards. In multivariate analyses, an absence of comorbidities (none versus any comorbidity [OR (95%CI), 0.565 (0.329-0.970)], p = 0.038) and of dyspnea (0.544 (0.341-0.868)], p = 0.011) were associated with increased risk of influenza positivity. Overall, 184/1106 (16.6%) patients were admitted to intensive care or high-dependency units (ICU/HDU) (13.2% were influenza positive) and 26/1106 (2.4%) died (2.6% were influenza positive). Males were more likely to have a severe outcome (ICU/HDU admission or death). CONCLUSIONS: Influenza was a significant contributor to hospitalizations associated with CAP, AECOPD and AEBA. However, it was not associated with ICU/HDU admission in this population. Study registration, NMRR ID: NMRR-17-889-35,174.


Asunto(s)
Asma/complicaciones , Infecciones Comunitarias Adquiridas/complicaciones , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana/complicaciones , Neumonía/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Adulto , Anciano , Preescolar , Hospitalización , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad
5.
Brain ; 141(4): 1028-1039, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29394316

RESUMEN

Many studies support the pro-nociceptive role of brain-derived neurotrophin factor (BDNF) in pain processes in the peripheral and central nervous system. We have previously shown that nociceptor-derived BDNF is involved in inflammatory pain. Microglial-derived BDNF has also been shown to be involved in neuropathic pain. However, the distinct contribution of primary afferent-derived BNDF to chronic pain processing remains undetermined. In this study, we used Avil-CreERT2 mice to delete Bdnf from all adult peripheral sensory neurons. Conditional BDNF knockouts were healthy with no sensory neuron loss. Behavioural assays and in vivo electrophysiology indicated that spinal excitability was normal. Following formalin inflammation or neuropathy with a modified Chung model, we observed normal development of acute pain behaviour, but a deficit in second phase formalin-induced nocifensive responses and a reversal of neuropathy-induced mechanical hypersensitivity during the later chronic pain phase in conditional BDNF knockout mice. In contrast, we observed normal development of acute and chronic neuropathic pain in the Seltzer model, indicating differences in the contribution of BDNF to distinct models of neuropathy. We further used a model of hyperalgesic priming to examine the contribution of primary afferent-derived BDNF in the transition from acute to chronic pain, and found that primed BDNF knockout mice do not develop prolonged mechanical hypersensitivity to an inflammatory insult. Our data suggest that BDNF derived from sensory neurons plays a critical role in mediating the transition from acute to chronic pain.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Dolor Crónico/patología , Ganglios Espinales/patología , Células Receptoras Sensoriales/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Carragenina/toxicidad , Dolor Crónico/inducido químicamente , Modelos Animales de Enfermedad , Femenino , Formaldehído/toxicidad , Hiperalgesia/etiología , Masculino , Ratones , Ratones Transgénicos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Dimensión del Dolor
6.
Genome Res ; 23(10): 1749-62, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23800452

RESUMEN

We have created a library of 2007 mutagenized Caenorhabditis elegans strains, each sequenced to a target depth of 15-fold coverage, to provide the research community with mutant alleles for each of the worm's more than 20,000 genes. The library contains over 800,000 unique single nucleotide variants (SNVs) with an average of eight nonsynonymous changes per gene and more than 16,000 insertion/deletion (indel) and copy number changes, providing an unprecedented genetic resource for this multicellular organism. To supplement this collection, we also sequenced 40 wild isolates, identifying more than 630,000 unique SNVs and 220,000 indels. Comparison of the two sets demonstrates that the mutant collection has a much richer array of both nonsense and missense mutations than the wild isolate set. We also find a wide range of rDNA and telomere repeat copy number in both sets. Scanning the mutant collection for molecular phenotypes reveals a nonsense suppressor as well as strains with higher levels of indels that harbor mutations in DNA repair genes and strains with abundant males associated with him mutations. All the strains are available through the Caenorhabditis Genetics Center and all the sequence changes have been deposited in WormBase and are available through an interactive website.


Asunto(s)
Caenorhabditis elegans/genética , Genes de Helminto , Mutación , Alelos , Animales , Caenorhabditis elegans/clasificación , Codón sin Sentido , Variaciones en el Número de Copia de ADN , ADN Ribosómico , Bases de Datos de Ácidos Nucleicos , Genes Esenciales , Genes Supresores , Variación Genética , Genoma de los Helmintos , Genoma Mitocondrial , Heterocigoto , Mutación INDEL , Masculino , Mutación Missense , Fenotipo , Polimorfismo de Nucleótido Simple , Secuencias Repetidas en Tándem
7.
Appl Environ Microbiol ; 78(16): 5967-71, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22706052

RESUMEN

Geobacter sulfurreducens can form electrically conductive biofilms, but the potential for conductivity through mixed-species biofilms has not been examined. A current-producing biofilm grown from a wastewater sludge inoculum was highly conductive with low charge transfer resistance even though microorganisms other than Geobacteraceae accounted for nearly half the microbial community.


Asunto(s)
Biopelículas , Conductividad Eléctrica , Consorcios Microbianos/fisiología , Aguas del Alcantarillado/microbiología
8.
EMBO Rep ; 11(10): 777-83, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20829881

RESUMEN

ΔNp63α is a critical pro-survival protein overexpressed in 80% of head and neck squamous cell carcinomas (HNSCCs) where it inhibits TAp73ß transcription of p53-family target genes, which is thought to increase HNSCC resistance to chemotherapy-induced cell death. However, the mechanisms governing ΔNp63α function are largely unknown. In this study, we identify special AT-rich-binding protein 2 (SATB2) as a new ΔNp63α-binding protein that is preferentially expressed in advanced-stage primary HNSCC and show that SATB2 promotes chemoresistance by enhancing ΔNp63α-mediated transrepression by augmenting ΔNp63α engagement to p53-family responsive elements. Furthermore, SATB2 expression positively correlates with HNSCC chemoresistance, and RNA interference-mediated knockdown of endogenous SATB2 re-sensitizes HNSCC cells to chemotherapy- and γ-irradiation-induced apoptosis, irrespective of p53 status. These findings unveil SATB2 as a pivotal modulator of ΔNp63α that governs HNSCC cell survival.


Asunto(s)
Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Apoptosis , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Resistencia a Antineoplásicos , Genes p53 , Humanos , Transactivadores/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética
9.
Otol Neurotol ; 43(3): 359-367, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35147607

RESUMEN

INTRODUCTION: Vestibular migraine (VM) is a common condition; individuals experience dizziness with migraine symptoms. Vestibular rehabilitation therapy (VRT) has been reported as an effective treatment for VM, however, evidence is limited. VM and traumatic brain injury (TBI) can co-occur, and some suggest that TBI can induce VM. There is limited evidence on the effect a history of TBI has on VRT in patients with VM. METHODS: Retrospective case series of 93 (f = 63, m = 30) participants with VM and underwent VRT (mean age 48.62; SD 15.92). Pre- and post-treatment self-reported outcome measures and functional gait assessment were extracted from the participants health records and evaluated. The impact of TBI on VRT outcome in participants with VM was analyzed. Individuals with TBI and no history of migraine (n = 40) were also extracted to act as a control. RESULTS: VRT significantly improved self-reported dizziness on the Dizziness Handicap Inventory (DHI), with a mean change of -18 points (p < 0.000) and +5 points on the functional gait assessment (FGA) (p < 0.000) in patients with VM. A history of TBI significantly impacted outcome on the DHI (p = 0.018) in patients with VM.VRT significantly improved all outcome measures for individuals with TBI, with a mean change of -16 points on the DHI (p = 0.001) and +5 points on the FGA (p < 0.000). VM presence significantly impacted outcome. CONCLUSION: VRT should be considered as a treatment option to reduce dizziness and the risk of falls in individuals with VM. TBI may negatively impact VRT outcomes in individuals with VM.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Trastornos Migrañosos , Enfermedades Vestibulares , Lesiones Traumáticas del Encéfalo/complicaciones , Mareo/diagnóstico , Humanos , Persona de Mediana Edad , Trastornos Migrañosos/complicaciones , Trastornos Migrañosos/diagnóstico , Estudios Retrospectivos , Vértigo/complicaciones , Enfermedades Vestibulares/complicaciones , Enfermedades Vestibulares/diagnóstico
10.
Mol Pain ; 7: 100, 2011 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-22188729

RESUMEN

BACKGROUND: Tissue-specific gene deletion has proved informative in the analysis of pain pathways. Advillin has been shown to be a pan-neuronal marker of spinal and cranial sensory ganglia. We generated BAC transgenic mice using the Advillin promoter to drive a tamoxifen-inducible CreERT2 recombinase construct in order to be able to delete genes in adult animals. We used a floxed stop ROSA26LacZ reporter mouse to examine functional Cre expression, and analysed the behaviour of mice expressing Cre recombinase. RESULTS: We used recombineering to introduce a CreERT2 cassette in place of exon 2 of the Advillin gene into a BAC clone (RPCI23-424F19) containing the 5' region of the Advillin gene. Transgenic mice were generated using pronuclear injection. The resulting AvCreERT2 transgenic mice showed a highly specific expression pattern of Cre activity after tamoxifen induction. Recombinase activity was confined to sensory neurons and no expression was found in other organs. Less than 1% of neurons showed Cre expression in the absence of tamoxifen treatment. Five-day intraperitoneal treatment with tamoxifen (2 mg per day) induced Cre recombination events in ≈90% of neurons in dorsal root and cranial ganglia. Cell counts of dorsal root ganglia (DRG) from transgenic animals with or without tamoxifen treatment showed no neuronal cell loss. Sensory neurons in culture showed ≈70% induction after 3 days treatment with tamoxifen. Behavioural tests showed no differences between wildtype, AvCreERT2 and tamoxifen-treated animals in terms of motor function, responses to light touch and noxious pressure, thermal thresholds as well as responses to inflammatory agents. CONCLUSIONS: Our results suggest that the inducible pan-DRG AvCreERT2 deleter mouse strain is a useful tool for studying the role of individual genes in adult sensory neuron function. The pain phenotype of the Cre-induced animal is normal; therefore any alterations in pain processing can be unambiguously attributed to loss of the targeted gene.


Asunto(s)
Ganglios Sensoriales/efectos de los fármacos , Eliminación de Gen , Proteínas de Microfilamentos/genética , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/genética , Tamoxifeno/farmacología , Animales , Células Cultivadas , Ganglios Sensoriales/metabolismo , Integrasas/genética , Integrasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/metabolismo , Recombinación Genética , Células Receptoras Sensoriales/metabolismo
11.
Nephrol Dial Transplant ; 25(12): 4002-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20530806

RESUMEN

BACKGROUND: Anaemia is a common complication of chronic kidney disease. A number of studies have identified an adverse association between haemoglobin (Hgb) variability and mortality. To date, no study has evaluated the impact of Hgb variability on mortality in the setting of a uniform Hgb target and erythropoiesis-stimulating agents (ESA) dosing strategy. METHODS: One hundred and fifty-four haemodialysis (HD) patients from a previous randomized anaemia management study were followed up for up to 6 years. The impact of Hgb variability and ESA dosing parameters on subsequent mortality risk were evaluated. RESULTS: More rapid rises in Hgb (Hgb deflect(pos)) and ESA dose increases were independently associated with mortality in multivariate analysis, whereas more rapid Hgb declines (Hgb deflect(neg)) and ESA dose decreases were not. Each gram per litre per week increase in Hgb deflect(pos) was associated with an adjusted hazard ratio (HR) of 1.23 (1.03-1.48), while for every 1000-unit increase in ESA dose, the adjusted HR was 1.12 (1.01-1.24). Factors associated with positive Hgb deflections included frequency and magnitude of ESA dose changes, baseline Hgb, patient weight and presence of an HD catheter. CONCLUSIONS: Rapid Hgb rises and greater average Eprex dose increases were independently associated with a higher mortality risk in HD patients after adjustment for baseline Hgb and Eprex dose. A randomized controlled trial evaluating different ESA dosing strategies in response to individual patient ESA responsiveness is needed.


Asunto(s)
Anemia Ferropénica/etiología , Anemia Ferropénica/prevención & control , Eritropoyetina/uso terapéutico , Hemoglobinas/metabolismo , Enfermedades Renales/complicaciones , Enfermedades Renales/mortalidad , Anciano , Anemia Ferropénica/sangre , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Enfermedades Renales/terapia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Diálisis Renal , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
12.
Case Rep Neurol Med ; 2020: 5843089, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32655958

RESUMEN

Intractable epilepsy remains a significant medical challenge, resulting in recurrent and prolonged intensive care unit (ICU) admissions. Autoimmune encephalitis is emerging as a treatable cause of intractable epilepsy. It is characterized by antibodies against cerebral antigens, such as potassium channels such as leucine-rich, glioma inactivated 1 (LGI1) and contactin-associated protein 2 (CASPR2), calcium channels such as the voltage-gated calcium channel (VGCC), or neurotransmitter receptors such as the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), gamma aminobutyric acid receptor (GABAR), and N-methyl-D-aspartate receptor (NMDAR). Diagnosis requires a syndrome consistent with an antibody identified in serum or cerebrospinal fluid (CSF) using methods that minimize risk of false-positives. Although there is no officially approved therapy for these disorders, typical approaches involve chronic high-dose steroids, intravenous immunoglobulin (IVIG), or plasma exchange. Rituximab is effective for antibody-associated disorders such as lupus, myasthenia gravis, and neuromyelitis optica. Here, we present three patients who were admitted with recalcitrant status epilepticus and demonstrated serum antibodies against NMDAR, LGI1, or VGCC using a cell-based assay. All patients demonstrated complete, long-term epilepsy control and improvement in symptoms with rituximab.

13.
J Virol ; 82(9): 4343-53, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18287238

RESUMEN

X-box binding protein 1 (XBP-1), a basic leucine zipper transcription factor, plays a key role in the cellular unfolded protein response (UPR). There are two XBP-1 isoforms in cells, spliced XBP-1S and unspliced XBP-1U. XBP-1U has been shown to bind to the 21-bp Tax-responsive element of the human T-lymphotropic virus type 1 (HTLV-1) long terminal repeat (LTR) in vitro and transactivate HTLV-1 transcription. Here we identify XBP-1S as a transcription activator of HTLV-1. Compared to XBP-1U, XBP-1S demonstrates stronger activating effects on both basal and Tax-activated HTLV-1 transcription in cells. Our results show that both XBP-1S and XBP-1U interact with Tax and bind to the HTLV-1 LTR in vivo. In addition, elevated mRNA levels of the gene for XBP-1 and several UPR genes were detected in the HTLV-1-infected C10/MJ and MT2 T-cell lines, suggesting that HTLV-1 infection may trigger the UPR in host cells. We also identify Tax as a positive regulator of the expression of the gene for XBP-1. Activation of the UPR by tunicamycin showed no effect on the HTLV-1 LTR, suggesting that HTLV-1 transcription is specifically regulated by XBP-1. Collectively, our study demonstrates a novel host-virus interaction between a cellular factor XBP-1 and transcriptional regulation of HTLV-1.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Productos del Gen tax/fisiología , Virus Linfotrópico T Tipo 1 Humano/genética , Proteínas Nucleares/fisiología , Línea Celular , Proteínas de Unión al ADN/genética , Regulación Viral de la Expresión Génica , Infecciones por HTLV-I/genética , Humanos , Proteínas Nucleares/genética , ARN Viral/análisis , Factores de Transcripción del Factor Regulador X , Secuencias Repetidas Terminales , Factores de Transcripción , Transcripción Genética , Activación Transcripcional , Proteína 1 de Unión a la X-Box
14.
Steroids ; 74(3): 329-34, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19010339

RESUMEN

19-Norandrosterone (19-NA) is the principal urinary metabolite of the anabolic steroid nandrolone and its prohormones. The administration of these 19-nor androgens is prohibited in sport by the World Anti-Doping Agency (WADA) but, even so, adverse findings for 19-NA continue to be commonly reported. Little is known about the urinary concentrations of 19-NA that can occur in women who are not using anabolic steroids, including those using oral contraceptives containing the 19-nor progestogen norethisterone. In 2004, WADA lowered the reporting threshold for 19-NA for females from 5 to 2ng/mL. The lack of any substantial data on 19-NA excretion in women prompted this large-scale investigation. In this investigation, single untimed urines collected from 1202 female volunteers, 38 of whom were taking norethisterone containing contraceptives, were analysed for 19-NA. None of the women was a competitive athlete and pregnancy had been excluded by a urinary test for human chorionic gonadotropin (hCG). Only one sample exceeded the 19-NA reporting threshold having a concentration of 4.1ng/mL. This sample was from a user of a norethisterone-containing contraceptive.


Asunto(s)
Anticonceptivos Femeninos/orina , Doping en los Deportes , Estranos/orina , Noretindrona/orina , Detección de Abuso de Sustancias/métodos , Adolescente , Adulto , Anticonceptivos Femeninos/administración & dosificación , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Noretindrona/administración & dosificación , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Adulto Joven
15.
Steroids ; 74(3): 335-40, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19010341

RESUMEN

The finding of measurable amounts of 19-norandrostenedione in norethisterone tablets prompted us to develop an assay to quantify this steroid. 19-Norandrostenedione is an anabolic steroid whose use in sport is prohibited by the World Anti-Doping Agency (WADA). The assay was developed using isotope dilution and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantification of 19-norandrostenedione in norethisterone formulations, with [3,4-(13)C(2)]-19-norandrostenedione as the internal standard. The results showed amounts up to 1.01+/-0.01microg (mean+/-S.E.M.) per tablet in those containing 5mg of norethisterone or norethisterone acetate (0.02%, w/w) and up to 0.5+/-0.01microg (mean+/-S.E.M.) per tablet (0.05%, w/w) in oral contraceptive tablets containing 0.35-1.5mg of norethisterone or norethisterone acetate. No tablet tested exceeded the British Pharmacopoeia limit of 0.1% for this impurity.


Asunto(s)
Androstenodiona/análogos & derivados , Doping en los Deportes , Noretindrona/análisis , Noretindrona/química , Preparaciones Farmacéuticas/análisis , Androstenodiona/análisis , Androstenodiona/química , Cromatografía Liquida , Estructura Molecular , Preparaciones Farmacéuticas/química , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
16.
Steroids ; 74(3): 341-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19059424

RESUMEN

The detection of 19 norandrosterone (19-NA) in a competitor's urine sample is taken as prima facie evidence of administration of nandrolone or other 19-norsteroid but a potential problem is that administration of norethisterone, a progestogen used for menstrual disorders and for hormonal contraception, also results in the excretion of 19-NA that can exceed the laboratory reporting threshold of 2ng/mL. The contribution of norethisterone to urinary 19-NA with and without 19-norandrostenedione, a known norethisterone tablet impurity, requires evaluation. Preparations containing, either <2ng or 1microg 19-norandrostenedione impurity per 5mg of norethisterone, administered to female volunteers (n=10) in doses comparable to those used for menstrual disorders (5mg three times daily for 10 days), resulted in maximal 19-NA concentrations of 51 and 63ng/mL, respectively. The maximal concentration of 19-NA, 2h post-administration of a single 1microg dose of 19-norandrostenedione, was 2.4ng/mL. These results prove unequivocally that norethisterone is metabolized to 19-NA and that there is only a minor contribution from the impurity 19-norandrostenedione. Administration to women (n=30) of a single contraceptive tablet containing norethisterone (1mg) with one of the highest proportions of the impurity 19-norandrostenedione ( approximately 0.5microg, 0.05%, w/w) resulted in a urinary 19-NA concentration of 9.1ng/mL, with a maximum concentration ratio of 19-NA to the norethisterone metabolite 3alpha,5beta-tetrahydronorethisterone of 0.36. We provide data that should remove the need for time-consuming follow-up investigations to consider whether doping with 19-norandrogens has occurred.


Asunto(s)
Administración Oral , Doping en los Deportes , Estranos/metabolismo , Estranos/orina , Noretindrona/metabolismo , Noretindrona/orina , Adulto , Cromatografía Liquida , Estranos/administración & dosificación , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Estructura Molecular , Espectrometría de Masas en Tándem , Adulto Joven
17.
Cancer Res ; 79(19): 4994-5007, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31391185

RESUMEN

Human astrocytomas and oligodendrogliomas are defined by mutations of the metabolic enzymes isocitrate dehydrogenase (IDH) 1 or 2, resulting in the production of the abnormal metabolite D-2 hydroxyglutarate. Here, we studied the effect of mutant IDH on cell proliferation and apoptosis in a glioma mouse model. Tumors were generated by inactivating Pten and p53 in forebrain progenitors and compared with tumors additionally expressing the Idh1 R132H mutation. Idh-mutant cells proliferated less in vitro and mice with Idh-mutant tumors survived significantly longer compared with Idh-wildtype mice. Comparison of miRNA and RNA expression profiles of Idh-wildtype and Idh-mutant cells and tumors revealed miR-183 was significantly upregulated in IDH-mutant cells. Idh-mutant cells were more sensitive to endoplasmic reticulum (ER) stress, resulting in increased apoptosis and thus reduced cell proliferation and survival. This was mediated by the interaction of miR-183 with the 5' untranslated region of semaphorin 3E, downregulating its function as an apoptosis suppressor. In conclusion, we show that mutant Idh1 delays tumorigenesis and sensitizes tumor cells to ER stress and apoptosis. This may open opportunities for drug treatments targeting the miR-183-semaphorin axis. SIGNIFICANCE: The pathologic metabolite 2-hydroxyglutarate, generated by IDH-mutant astrocytomas, sensitizes tumor cells to ER stress and delays tumorigenesis. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/19/4994/F1.large.jpg.


Asunto(s)
Neoplasias Encefálicas/patología , Estrés del Retículo Endoplásmico/genética , Glioma/patología , Isocitrato Deshidrogenasa/genética , MicroARNs/metabolismo , Semaforinas/metabolismo , Animales , Apoptosis/genética , Neoplasias Encefálicas/genética , Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glutaratos/metabolismo , Ratones , Ratones Mutantes , Mutación
18.
J Innov Card Rhythm Manag ; 9(2): 3016-3021, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32477796

RESUMEN

Cardiac sarcoidosis (CS) can cause atrial and ventricular arrhythmias, conduction system disease, and congestive heart failure. The use of advanced imaging modalities including cardiac magnetic resonance and positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose can be helpful in evaluating the extent of disease and response to treatment. The management of CS patients can be challenging, requiring immunosuppression medications, antiarrhythmic drugs, implantable cardiac devices, and cardiac ablation procedures. We report a patient with CS initially presenting with paroxysmal atrial fibrillation who later developed polymorphic ventricular tachycardia, highlighting the complexity of diagnosis and management in patients with multisystem sarcoidosis.

19.
J Thorac Cardiovasc Surg ; 155(1): 291-300.e3, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28918207

RESUMEN

OBJECTIVE: To assess the trajectory of perioperative brain growth in relationship to cardiac diagnosis and acquired brain injuries. METHODS: This was a cohort study of term neonates with hypoplastic left heart syndrome (HLHS) and d-transposition of the great arteries (d-TGA). Subjects underwent magnetic resonance imaging of the brain pre- and postoperatively to determine the severity of brain injury and total and regional brain volumes by the use of automated morphometry. Comparisons were made by cardiac lesion and injury status. RESULTS: A total of 79 subjects were included (49, d-TGA; 30, HLHS). Subjects with HLHS had more postoperative brain injury (55.6% vs 30.4%, P = .03) and more severe brain injury (moderate-to-severe white matter [WM] injury, P = .01). Total and regional perioperative brain growth was not different by brain injury status (either pre- or postoperative). However, subjects with moderate-to-severe WM injury had a slower rate of brain growth in WM and gray matter compared with those with no injury. Subjects with HLHS had a slower rate of growth globally and in WM and deep gray matter as compared with d-TGA (total brain volume: 12 cm3/wk vs 7 cm3; WM: 2.1 cm3/wk vs 0.6 cm3; deep gray matter: 1.5 cm3/wk vs 0.7 cm3; P < .001), after we adjusted for gestational age at scan and the presence of brain injury. This difference remained after excluding subjects with moderate-to-severe WM injury. CONCLUSIONS: Neonates with HLHS have a slower rate of global and regional brain growth compared with d-TGA, likely related to inherent physiologic differences postoperatively. These findings demonstrate the complex interplay between cardiac lesion, brain injury, and brain growth.


Asunto(s)
Lesiones Encefálicas , Encéfalo , Sistema Cardiovascular/fisiopatología , Síndrome del Corazón Izquierdo Hipoplásico/cirugía , Transposición de los Grandes Vasos , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Lesiones Encefálicas/diagnóstico , Lesiones Encefálicas/etiología , California , Estudios de Cohortes , Correlación de Datos , Femenino , Edad Gestacional , Humanos , Síndrome del Corazón Izquierdo Hipoplásico/fisiopatología , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino , Atención Perioperativa/métodos , Complicaciones Posoperatorias/diagnóstico , Transposición de los Grandes Vasos/fisiopatología , Transposición de los Grandes Vasos/cirugía
20.
Placenta ; 65: 65-75, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29908643

RESUMEN

Chorionic villus sampling (CVS), routinely used for prenatal diagnosis of cytogenetic disorders, also possesses great potential for the study of placentation. To better understand villus biology, human placentation, and how these relate to pregnancy outcomes, we examined the morphology and transcriptomes of villi obtained via CVS from 10 to 14 weeks of pregnancy and correlated these with pregnancy attributes and clinical outcomes. First, we established a morphological scoring system based on three main villus features: branching, budding and vascularization. We then tested whether morphology scores were predictive of pregnancy attributes and clinical outcomes. Finally, we used RNA sequencing to assess the transcriptional basis of villus morphology and tested the hypothesis that gene expression may predict pregnancy outcomes. We demonstrate that villus morphology varies tremendously between patients, irrespective of gestational age, and that transcriptional differences are highly predictive of villus morphology. We show that pre-eclampsia markers are associated with villi with low morphology scores. Additionally, we identify SVEP1 as a possible biomarker for defining gestational age. Overall, chorionic villi in the first trimester remain one of the few means to correlate placental function with pregnancy outcome and these samples are a valuable and increasingly rare resource.


Asunto(s)
Vellosidades Coriónicas/metabolismo , Vellosidades Coriónicas/patología , Placenta/metabolismo , Placentación/genética , Primer Trimestre del Embarazo/genética , Adulto , Biomarcadores/metabolismo , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Vellosidades Coriónicas/irrigación sanguínea , Vellosidades Coriónicas/crecimiento & desarrollo , Muestra de la Vellosidad Coriónica , Análisis Citogenético , Femenino , Perfilación de la Expresión Génica , Edad Gestacional , Humanos , Masculino , Tamaño de los Órganos , Placenta/patología , Embarazo , Resultado del Embarazo/genética , Diagnóstico Prenatal , Análisis de Secuencia de ARN
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