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1.
Mol Plant Microbe Interact ; 28(11): 1181-97, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26168138

RESUMEN

Trichoderma species are often used as biocontrol agents against plant-pathogenic fungi. A complex molecular interaction occurs among the biocontrol agent, the antagonistic fungus, and the plant. Terpenes and sterols produced by the biocontrol fungus have been found to affect gene expression in both the antagonistic fungus and the plant. The terpene trichodiene (TD) elicits the expression of genes related to tomato defense and to Botrytis virulence. We show here that TD itself is able to induce the expression of Botrytis genes involved in the synthesis of botrydial (BOT) and also induces terpene gene expression in Trichoderma spp. The terpene ergosterol, in addition to its role as a structural component of the fungal cell membranes, acts as an elicitor of defense response in plants. In the present work, using a transformant of T. harzianum, which is silenced in the erg1 gene and accumulates high levels of squalene, we show that this ergosterol precursor also acts as an important elicitor molecule of tomato defense-related genes and induces Botrytis genes involved in BOT biosynthesis, in both cases, in a concentration-dependent manner. Our data emphasize the importance of a balance of squalene and ergosterol in fungal interactions as well as in the biocontrol activity of Trichoderma spp.


Asunto(s)
Ciclohexenos/metabolismo , Ergosterol/biosíntesis , Proteínas Fúngicas/genética , Sesquiterpenos/metabolismo , Solanum lycopersicum/genética , Trichoderma/genética , Vías Biosintéticas/genética , Botrytis/genética , Botrytis/metabolismo , Botrytis/fisiología , Resistencia a la Enfermedad/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Interacciones Huésped-Patógeno/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Escualeno/metabolismo , Trichoderma/metabolismo , Trichoderma/fisiología
2.
Appl Environ Microbiol ; 81(18): 6355-66, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26150463

RESUMEN

Trichothecenes are fungal sesquiterpenoid compounds, the majority of which have phytotoxic activity. They contaminate food and feed stocks, resulting in potential harm to animals and human beings. Trichoderma brevicompactum and T. arundinaceum produce trichodermin and harzianum A (HA), respectively, two trichothecenes that show different bioactive properties. Both compounds have remarkable antibiotic and cytotoxic activities, but in addition, trichodermin is highly phytotoxic, while HA lacks this activity when analyzed in vivo. Analysis of Fusarium trichothecene intermediates led to the conclusion that most of them, with the exception of the hydrocarbon precursor trichodiene (TD), have a detectable phytotoxic activity which is not directly related to the structural complexity of the intermediate. In the present work, the HA intermediate 12,13-epoxytrichothec-9-ene (EPT) was produced by expression of the T. arundinaceum tri4 gene in a transgenic T. harzianum strain that already produces TD after transformation with the T. arundinaceum tri5 gene. Purified EPT did not show antifungal or phytotoxic activity, while purified HA showed both antifungal and phytotoxic activities. However, the use of the transgenic T. harzianum tri4 strain induced a downregulation of defense-related genes in tomato plants and also downregulated plant genes involved in fungal root colonization. The production of EPT by the transgenic tri4 strain raised levels of erg1 expression and reduced squalene accumulation while not affecting levels of ergosterol. Together, these results indicate the complex interactions among trichothecene intermediates, fungal antagonists, and host plants.


Asunto(s)
Genes Fúngicos , Solanum lycopersicum/genética , Trichoderma/genética , Trichoderma/fisiología , Tricotecenos/biosíntesis , Antifúngicos/metabolismo , Ciclohexenos/metabolismo , Regulación hacia Abajo , Ergosterol/metabolismo , Fusarium/química , Fusarium/metabolismo , Regulación Fúngica de la Expresión Génica , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/crecimiento & desarrollo , Mutación , Sesquiterpenos/metabolismo , Escualeno/análisis , Tricodermina/metabolismo , Tricodermina/toxicidad , Tricotecenos/metabolismo , Tricotecenos/farmacología , Tricotecenos/toxicidad
3.
Nature ; 462(7273): 620-3, 2009 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-19935645

RESUMEN

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated gamma-ray emission. Galactic 'microquasars', which are binary systems consisting of a neutron star or stellar-mass black hole accreting gas from a companion star, also produce relativistic jets, generally together with radio flares. Apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar, with the consequence that we are as yet unsure about the mechanism of jet energization. Here we report four gamma-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 (an exceptional X-ray binary that sporadically produces radio jets). There is a clear pattern of temporal correlations between the gamma-ray flares and transitional spectral states of the radio-frequency and X-ray emission. Particle acceleration occurred a few days before radio-jet ejections for two of the four flares, meaning that the process of jet formation implies the production of very energetic particles. In Cygnus X-3, particle energies during the flares can be thousands of times higher than during quiescent states.

4.
BMC Genomics ; 14: 792, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24228692

RESUMEN

BACKGROUND: Gene copy number variation plays a large role in the evolution of genomes. In Rattus norvegicus and other rodent species, the Y-chromosome has accumulated multiple copies of Sry loci. These copy number variations have been previously linked with changes in phenotype of animal models such as the spontaneously hypertensive rat (SHR). This study characterizes the Y-chromosome in the Sry region of Rattus norvegicus, while addressing functional variations seen in the Sry protein products. RESULTS: Eleven Sry loci have been identified in the SHR with one (nonHMG Sry) containing a frame shift mutation. The nonHMGSry is found and conserved in the related WKY and SD rat strains. Three new, previously unidentified, Sry loci were identified in this study (Sry3BII, Sry4 and Sry4A) in both SHR and WKY. Repetitive element analysis revealed numerous LINE-L1 elements at regions where conservation is lost among the Sry copies. In addition we have identified a retrotransposed copy of Med14 originating from spliced mRNA, two autosomal genes (Ccdc110 and HMGB1) and a normal mammalian Y-chromosome gene (Zfy) in the Sry region of the rat Y-chromosome. Translation of the sequences of each Sry gene reveals eight proteins with amino acid differences leading to changes in nuclear localization and promoter activation of a Sry-responsive gene. Sry-ß (coded by the Sry2 locus) has an increased cytoplasmic fraction due to alterations at amino acid 21. Sry-γ has altered gene regulation of the Sry1 promoter due to changes at amino acid 76. CONCLUSIONS: The duplication of Sry on the Rattus norvegicus Y-chromosome has led to proteins with altered functional ability that may have been selected for functions in addition to testis determination. Additionally, several other genes not normally found on the Y-chromosome have duplicated new copies into the region around the Sry genes. These suggest a role of active transposable elements in the evolution of the mammalian Y-chromosome in species such as Rattus norvegicus.


Asunto(s)
Variaciones en el Número de Copia de ADN/genética , Proteína de la Región Y Determinante del Sexo/genética , Cromosoma Y/genética , Animales , Secuencia de Bases , Proteínas de Unión al ADN , Regulación de la Expresión Génica , Humanos , Masculino , Ratas , Ratas Endogámicas SHR , Proteína de la Región Y Determinante del Sexo/biosíntesis , Testículo/metabolismo
5.
Appl Environ Microbiol ; 78(14): 4856-68, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22562989

RESUMEN

Trichoderma species produce trichothecenes, most notably trichodermin and harzianum A (HA), by a biosynthetic pathway in which several of the involved proteins have significant differences in functionality compared to their Fusarium orthologues. In addition, the genes encoding these proteins show a genomic organization differing from that of the Fusarium tri clusters. Here we describe the isolation of Trichoderma arundinaceum IBT 40837 transformants which have a disrupted or silenced tri4 gene, a gene encoding a cytochrome P450 monooxygenase that oxygenates trichodiene to give rise to isotrichodiol, and the effect of tri4 gene disruption and silencing on the expression of other tri genes. Our results indicate that the tri4 gene disruption resulted in a reduced antifungal activity against Botrytis cinerea and Rhizoctonia solani and also in a reduced ability to induce the expression of tomato plant defense-related genes belonging to the salicylic acid (SA) and jasmonate (JA) pathways against B. cinerea, in comparison to the wild-type strain, indicating that HA plays an important function in the sensitization of Trichoderma-pretreated plants against this fungal pathogen. Additionally, the effect of the interaction of T. arundinaceum with B. cinerea or R. solani and with tomato seedlings on the expressions of the tri genes was studied.


Asunto(s)
Antifúngicos/metabolismo , Regulación de la Expresión Génica de las Plantas , Control Biológico de Vectores , Enfermedades de las Plantas/inmunología , Solanum lycopersicum/microbiología , Trichoderma/metabolismo , Tricotecenos/metabolismo , Antifúngicos/farmacología , Botrytis/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Silenciador del Gen , Genes de Plantas , Solanum lycopersicum/inmunología , Enfermedades de las Plantas/microbiología , Rhizoctonia/efectos de los fármacos , Tricotecenos/farmacología
6.
Cad Saude Publica ; 38(7): e00286121, 2022.
Artículo en Portugués | MEDLINE | ID: mdl-35976348

RESUMEN

This is a paired case-control study that sought to verify the association between professions and lymphohematopoietic cancers in a public reference hospital in the State of Ceará, Brazil, during 2019-2021. Case group consisted of hematological patients with multiple myeloma, leukemias or non-Hodgkin lymphomas, monitored by the social service of a bone marrow transplant hospital unit (n = 114), whereas comparable individuals from a different hospital unit made up the control group (n = 114), forming 1:1 pairs. Diagnosis was performed by a medical team and the variables were measured by accessing hospital records. Group comparison was conducted using bivariate conditional logistic regression and adjusted by region of residence. Results show that multiple myeloma (43.9%), leukemias (43%) and non-Hodgkin lymphomas (13.2%) were the cancer with the highest prevalence in the case group. Proportions of jobs, area of residence, water supply and Regional Superintendence of Health showed statistically significant difference between the case and control groups. Rural workers were more likely to present the cancers studied (ORraw = 5.00, 95%CI: 1.91; 13.06 and ORadjusted = 3.38, 95%CI: 1.20; 9.54), whereas trade workers had lower odds (ORraw = 0.26, 95%CI: 0.10; 0.70 and ORadjusted = 0.30, 95%CI: 0.10; 0.88). The findings allow us to reflect on the process of illness among rural workers and illustrate the potential of health services to contribute to investigations on occupational exposures.


Trata-se de um estudo do tipo caso-controle pareado com o objetivo de verificar a associação entre ocupações e cânceres linfohematopoiéticos em um hospital público de referência no Estado do Ceará, Brasil, durante 2019-2021. O grupo caso foi constituído por pacientes hematológicos que apresentavam mieloma múltiplo, leucemias ou linfomas não Hodgkin, acompanhados pelo serviço social de uma unidade hospitalar de transplante de medula óssea (n = 114), enquanto indivíduos comparáveis de unidade hospitalar distinta constituíram o grupo controle (n = 114), formando pares 1:1. O diagnóstico foi efetuado por equipe médica e as variáveis foram aferidas por acesso aos registros hospitalares. Comparamos os grupos em regressão logística condicional bivariada e ajustada por região de residência. Entre os resultados, destacamos que o câncer de maior prevalência no grupo caso foi o mieloma múltiplo (43,9%), seguido pelas leucemias (43%) e por linfomas não Hodgkin (13,2%). Proporções de ocupações, zona de residência, abastecimento de água e Superintendência Regional de Saúde de residência apresentaram diferença estatisticamente significante entre os grupos caso e controle. Verificamos que trabalhadores rurais possuíam maiores chances de apresentar os cânceres estudados (ORbruto = 5,00, IC95%: 1,91; 13,06 e ORajustado = 3,38, IC95%: 1,20; 9,54), enquanto trabalhadores do comércio apresentaram menores chances (ORbruto = 0,26, IC95%: 0,10; 0,70 e ORajustado = 0,30, IC95%: 0,10; 0,88). Os achados deste estudo possibilitam reflexões sobre o processo de adoecimento dos trabalhadores rurais e refletem o potencial dos serviços de saúde em contribuir com investigações sobre exposições ocupacionais.


Se trata de un estudio del tipo caso control apareado con el objetivo de verificar la asociación entre ocupaciones y cánceres linfohematopoyéticos en un hospital público de referencia en el estado de Ceará, Brasil, durante el período 2019-2021. El grupo caso estaba formado por pacientes hematológicos que presentaban mieloma múltiple, leucemias o linfomas no Hodgkin, bajo seguimiento por parte del servicio social de una unidad hospitalaria de trasplante de médula ósea (n = 114), mientras que individuos comparables de otra unidad hospitalaria constituyeron el grupo control (n = 114), formando pares 1:1. El diagnóstico fue realizado por un equipo médico, y las variables se midieron accediendo a los registros hospitalarios. Comparamos los grupos en regresión logística condicional bivariada y ajustada por región de residencia. Entre los resultados, destacamos que el cáncer de mayor prevalencia en el grupo caso fue el mieloma múltiple (43,9%), seguido de las leucemias (43%) y los linfomas no Hodgkin (13,2%). Las proporciones de ocupaciones, zona de residencia, abastecimiento de agua y Superintendencia Regional de Salud de residencia presentaron diferencia estadísticamente significativa entre los grupos caso y control. Constatamos que los trabajadores rurales tenían más probabilidades de padecer los cánceres estudiados (ORcrudo = 5,00, IC95%: 1,91; 13,06 y ORajustado = 3,38, IC95%: 1,20; 9,54), mientras que los trabajadores del comercio presentaron menos posibilidades (ORcrudo = 0,26, IC95%: 0,10; 0,70 y ORajustado = 0,30, IC95%: 0,10; 0,88). Los hallazgos de este estudio permiten reflexiones sobre el proceso de enfermedad de los trabajadores rurales y reflejan el potencial de los servicios de salud para contribuir a las investigaciones sobre exposiciones ocupacionales.


Asunto(s)
Leucemia , Linfoma no Hodgkin , Mieloma Múltiple , Brasil/epidemiología , Estudios de Casos y Controles , Hospitales , Humanos , Leucemia/epidemiología , Linfoma no Hodgkin/epidemiología , Mieloma Múltiple/epidemiología
7.
Appl Environ Microbiol ; 77(9): 3009-16, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21421791

RESUMEN

The synthesis of reactive oxygen species (ROS) is one of the first events following pathogenic interactions in eukaryotic cells, and NADPH oxidases are involved in the formation of such ROS. The nox1 gene of Trichoderma harzianum was cloned, and its role in antagonism against phytopathogens was analyzed in nox1-overexpressed transformants. The increased levels of nox1 expression in these transformants were accompanied by an increase in ROS production during their direct confrontation with Pythium ultimum. The transformants displayed an increased hydrolytic pattern, as determined by comparing protease, cellulase, and chitinase activities with those for the wild type. In confrontation assays against P. ultimum the nox1-overexpressed transformants were more effective than the wild type, but not in assays against Botrytis cinerea or Rhizoctonia solani. A transcriptomic analysis using a Trichoderma high-density oligonucleotide (HDO) microarray also showed that, compared to gene expression for the interaction of wild-type T. harzianum and P. ultimum, genes related to protease, cellulase, and chitinase activities were differentially upregulated in the interaction of a nox1-overexpressed transformant with this pathogen. Our results show that nox1 is involved in T. harzianum ROS production and antagonism against P. ultimum.


Asunto(s)
Interacciones Microbianas , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Pythium/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Trichoderma/enzimología , Botrytis/efectos de los fármacos , Botrytis/crecimiento & desarrollo , Clonación Molecular , ADN de Hongos/química , ADN de Hongos/genética , Perfilación de la Expresión Génica , Datos de Secuencia Molecular , Control Biológico de Vectores , Pythium/crecimiento & desarrollo , Rhizoctonia/efectos de los fármacos , Rhizoctonia/crecimiento & desarrollo , Análisis de Secuencia de ADN , Trichoderma/genética
8.
Appl Environ Microbiol ; 77(14): 4867-77, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21642405

RESUMEN

Trichothecenes are mycotoxins produced by Trichoderma, Fusarium, and at least four other genera in the fungal order Hypocreales. Fusarium has a trichothecene biosynthetic gene (TRI) cluster that encodes transport and regulatory proteins as well as most enzymes required for the formation of the mycotoxins. However, little is known about trichothecene biosynthesis in the other genera. Here, we identify and characterize TRI gene orthologues (tri) in Trichoderma arundinaceum and Trichoderma brevicompactum. Our results indicate that both Trichoderma species have a tri cluster that consists of orthologues of seven genes present in the Fusarium TRI cluster. Organization of genes in the cluster is the same in the two Trichoderma species but differs from the organization in Fusarium. Sequence and functional analysis revealed that the gene (tri5) responsible for the first committed step in trichothecene biosynthesis is located outside the cluster in both Trichoderma species rather than inside the cluster as it is in Fusarium. Heterologous expression analysis revealed that two T. arundinaceum cluster genes (tri4 and tri11) differ in function from their Fusarium orthologues. The Tatri4-encoded enzyme catalyzes only three of the four oxygenation reactions catalyzed by the orthologous enzyme in Fusarium. The Tatri11-encoded enzyme catalyzes a completely different reaction (trichothecene C-4 hydroxylation) than the Fusarium orthologue (trichothecene C-15 hydroxylation). The results of this study indicate that although some characteristics of the tri/TRI cluster have been conserved during evolution of Trichoderma and Fusarium, the cluster has undergone marked changes, including gene loss and/or gain, gene rearrangement, and divergence of gene function.


Asunto(s)
Proteínas Fúngicas/biosíntesis , Micotoxinas/biosíntesis , Trichoderma/genética , Trichoderma/metabolismo , Tricotecenos/biosíntesis , Tricotecenos/genética , ADN de Hongos/biosíntesis , ADN de Hongos/genética , Proteínas Fúngicas/genética , Fusarium/genética , Fusarium/metabolismo , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Datos de Secuencia Molecular , Familia de Multigenes , Micotoxinas/genética , Reacción en Cadena de la Polimerasa , Alineación de Secuencia
9.
Am J Physiol Regul Integr Comp Physiol ; 301(3): R561-71, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21677270

RESUMEN

The Sry locus on the mammalian Y chromosome is the developmental switch responsible for testis determination. Inconsistent with this important function, the Sry locus is transcribed in adult males at times and in tissues not involved with testis determination. Sry is expressed in multiple tissues of the peripheral and central nervous system. Sry is derived from Sox3 and is similar to other SOXB family loci. The SOXB loci are responsible for nervous system development. Sry has been demonstrated to modulate the catecholamine pathway, so it should have functional consequences in the central and peripheral nervous system. The nervous system expression and potential function are consistent with Sry as a SOXB family member. In mammals, Sox3 is X-linked and undergoes dosage compensation in females. The expression of Sry in adult males allows for a type of sexual differentiation independent of circulating gonadal hormones. A quantitative difference in Sox3 plus Sry expression in males vs. females could drive changes in the transcriptome of these cells, differentiating male and female cells. Sry expression and its transcriptional effects should be considered when investigating sexual dimorphic phenotypes.


Asunto(s)
Proteína de la Región Y Determinante del Sexo/metabolismo , Transducción de Señal , Testículo/metabolismo , Cromosoma Y , Animales , Femenino , Regulación de la Expresión Génica , Genotipo , Humanos , Masculino , Sistema Nervioso/metabolismo , Sistemas Neurosecretores/metabolismo , Organogénesis , Fenotipo , Conformación Proteica , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Caracteres Sexuales , Procesos de Determinación del Sexo , Proteína de la Región Y Determinante del Sexo/química , Proteína de la Región Y Determinante del Sexo/genética , Testículo/embriología
10.
Phys Rev Lett ; 106(1): 018501, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21231775

RESUMEN

Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and γ rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere.

11.
J Neurol Neurosurg Psychiatry ; 82(12): 1355-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21622936

RESUMEN

BACKGROUND: The identification of biomarkers able to improve the differential diagnosis between multiple sclerosis (MS) and neuromyelitis optica (NMO) is challenging because of a different prognosis and response to treatment. Growing evidence indicates that brain and CSF N-acetyl aspartate (NAA) concentration is a useful marker for characterising different phases of axonal pathology in demyelinating diseases, and preliminary studies suggest that increased serum NAA levels may be a telltale sign of acute neuronal damage or defective NAA metabolism in oligodendrocytes. OBJECTIVE: To evaluate whether serum and CSF NAA concentration differs in patients with MS and NMO. DESIGN: Observational, multicentre, prospective, cross sectional study. METHODS: Serum samples were collected from 48 relapsing-remitting MS, 32 NMO and 76 age matched healthy controls. Coeval CSF samples were available for all MS and for 8/32 NMO patients. NAA was measured in serum and CSF by liquid chromatography-mass spectrometry. RESULTS: MS patients showed higher serum and CSF NAA levels than NMO patients, and higher serum NAA levels than healthy controls (p<0.001). High serum NAA values, exceeding the 95th percentile of serum NAA values in healthy controls, were found in 100% of patients with MS and in no patient with NMO. No differences in serum NAA levels were found between NMO and healthy controls. In MS, serum and CSF NAA levels correlated with disability score. CONCLUSIONS: Determination of serum and CSF NAA levels may represent a suitable tool in the diagnostic laboratory workup to differentiate MS and NMO.


Asunto(s)
Ácido Aspártico/análogos & derivados , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Neuromielitis Óptica/diagnóstico , Adolescente , Adulto , Anciano , Ácido Aspártico/sangre , Ácido Aspártico/líquido cefalorraquídeo , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/líquido cefalorraquídeo , Neuromielitis Óptica/sangre , Neuromielitis Óptica/líquido cefalorraquídeo
12.
Rev Neurol ; 73(12): 416-420, 2021 11 16.
Artículo en Español | MEDLINE | ID: mdl-34877644

RESUMEN

INTRODUCTION AND AIMS: Rituximab (RTX) is an anti-CD20 monoclonal antibody that has been used in cases of refractory myasthenia gravis (MG). The aim of this work is to analyse the efficacy and safety of RTX in MG in real clinical practice in a tertiary hospital. PATIENTS AND METHODS: A retrospective study was conducted with patients with MG treated with RTX in our centre from March 2014 to September 2020. Demographic and serological data, together with information about previous immunomodulatory treatment, clinical response and adverse effects are collected. RESULTS: Twenty patients with MG - 100% generalised: 70% late-onset MG (LOMG) and 30% early-onset MG (EOMG) - were given RTX (mean age: 66.8 years; 70% male). A total of 90% are seropositive, 16 of them with positive anti-acetylcholine receptor antibodies and two with positive muscle-specific tyrosine kinase (anti-MuSK) antibodies. All had failed previous treatments: 100% with steroids, 100% with intravenous immunoglobulins and/or plasmapheresis, 55% with other immunosuppressants (25% with one previous immunosuppressant, 10% with two, 15% with three and 5% with four) and 35% with thymectomy. After RTX, 75% of patients showed a clinical response (12 patients with complete remission and the possibility of steroid withdrawal without recurrence; and three patients with partial remission and the possible reduction of steroid dosage) and 25% therapeutic failure; in all these cases RTX was withdrawn. All the anti-MuSK+ patients (100%) and 92.8% of the LOMG patients responded to RTX, while 66% of EOMG patients failed. Only three patients reported adverse effects, all of which were mild and did not require RTX withdrawal. CONCLUSION: In our experience, rituximab is a safe and effective treatment in aggressive generalised MG with anti-MuSK or late-onset MG (LOMG).


TITLE: Rituximab para el tratamiento de la miastenia grave generalizada: experiencia en la práctica clínica.Introducción y objetivos. El rituximab (RTX) es un anticuerpo monoclonal anti-CD20 que se ha utilizado en casos de miastenia grave (MG) refractaria. El objetivo de este trabajo es analizar la eficacia y la seguridad del RTX en la MG en la práctica clínica real en un hospital terciario. Pacientes y métodos. Se realiza un estudio retrospectivo de pacientes con MG tratados con RTX en nuestro centro de marzo de 2014 a septiembre de 2020. Se recogen datos demográficos, serológicos, tratamiento inmunomodulador previo, respuesta clínica y efectos adversos. Resultados. Veinte pacientes con MG ­el 100%, generalizada: el 70%, MG de inicio tardío (LOMG), y el 30%, MG de inicio temprano (EOMG)­ han recibido RTX (edad media: 66,8 años; 70%, varones). El 90% son seropositivos ­16 con anticuerpos antirreceptor de la acetilcolina positivos y dos con anticuerpos antitirosincinasa muscular específica (anti-MuSK) positivos­. Todos habían fracasado con tratamientos previos: el 100% con esteroides, el 100% con inmunoglobulinas intravenosas y/o con plasmaféresis, el 55% con otros inmunosupresores (25%, un inmunosupresor previo; 10%, dos; 15%, tres; y 5%, cuatro) y el 35% con timectomía. Tras el RTX, presentó respuesta clínica el 75% de los pacientes (12 pacientes, remisión completa con posibilidad de la retirada de los esteroides sin recurrencia; y tres parcial, con posibilidad de la reducción de la dosis de esteroides) y fracaso terapéutico el 25%; en todos estos casos se retiró el RTX. El 100% de los pacientes anti-MuSK+ y el 92,8% de los de LOMG presentaron respuesta al RTX, mientras que el 66% de los pacientes con EOMG fracasaron. Sólo tres pacientes presentaron efectos adversos, todos leves, que no requirieron la retirada del RTX. Conclusión. En nuestra experiencia, el rituximab es un tratamiento seguro y eficaz en la MG generalizada agresiva con anticuerpos anti-MuSK o de inicio tardío (LOMG).


Asunto(s)
Miastenia Gravis/tratamiento farmacológico , Rituximab/uso terapéutico , Anciano , Femenino , Humanos , Masculino , Estudios Retrospectivos , Rituximab/efectos adversos , Resultado del Tratamiento
13.
Phys Rev Lett ; 105(12): 128501, 2010 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-20867680

RESUMEN

Terrestrial gamma-ray flashes (TGFs) are very short bursts of high-energy photons and electrons originating in Earth's atmosphere. We present here a localization study of TGFs carried out at gamma-ray energies above 20 MeV based on an innovative event selection method. We use the AGILE satellite Silicon Tracker data that for the first time have been correlated with TGFs detected by the AGILE Mini-Calorimeter. We detect 8 TGFs with gamma-ray photons of energies above 20 MeV localized by the AGILE gamma-ray imager with an accuracy of ∼5-10° at 50 MeV. Remarkably, all TGF-associated gamma rays are compatible with a terrestrial production site closer to the subsatellite point than 400 km. Considering that our gamma rays reach the AGILE satellite at 540 km altitude with limited scattering or attenuation, our measurements provide the first precise direct localization of TGFs from space.

14.
Mult Scler ; 16(1): 68-77, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19995846
16.
Thromb Res ; 174: 151-162, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30634166

RESUMEN

INTRODUCTION: Personalised pharmacokinetics (PK) using Bayesian analysis with limited sampling is assumed to help to optimise prophylaxis in haemophilia A (HA) patients. MATERIALS AND METHODS: Our prospective, observational study analysed the influence of PK parameters on clinical variables (bleeding rates, joint status, adherence, and consumption) using myPKFiT® in a cohort of twenty-one severe and moderate HA patients on prophylaxis with recombinant FVIII (Advate®) in two periods of one year, the first before PK-based tailoring and the second after PK-guided prophylaxis. Intra-individual and inter-individual coefficients of variation (CV) of half-life (t1/2) were calculated. RESULTS: A total of 73 PK estimations were performed in both periods, resulting in 17.2% inter-individual CV in mean t1/2, and 4.9% intra-individual CV. Before PK-based tailoring a significant association between joint bleeds and t1/2 was found (P = 0.010), especially in patients with short t1/2. This finding was reproduced (P = 0.013) after withdrawal of two patients with bleeding phenotype related to their advanced arthropathy but normal t1/2 and trough levels. Patients with joint bleeds weighed less (P = 0.039) and required higher doses (P = 0.032) than patients with zero joint bleeds. These associations were not observed in the second period after the adoption of PK-guided prophylaxis. There were no differences between the two periods, although a tendency to fewer spontaneous bleeds was suggested after PK-based tailoring. CONCLUSIONS: PK-guided prophylaxis facilitates an adequate level of bleeding control in patients with HA, maintaining clinical variables and patient convenience in an integrative manner, without increasing FVIII consumption.


Asunto(s)
Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Adolescente , Adulto , Anciano , Teorema de Bayes , Factor VIII/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
17.
Transplant Proc ; 40(9): 3090-3, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19010204

RESUMEN

BACKGROUND: Invasive fungal infections (IFIs) in patients undergoing lung transplantation (LT) are associated with significant mortality. Previous studies have shown the efficacy of aerosolized amphotericin B deoxycholate and oral fluconazole for antifungal prophylaxis. Evolving data show a potential advantage of prophylaxis with lipid-based formulations of amphotericin B in the prevention of IFIs. We reviewed the incidence of IFIs among patients receiving aerosolized amphotericin B lipid complex (ABLC) in LT. METHODS: We undertook a retrospective review of the results of our antifungal protocol in a cohort of 60 LT patients. We analyzed the efficiency, safety, and tolerability of 50 mg of aerosolized ABLC administered postoperatively for IFI prophylaxis once every 2 days for 2 weeks and then once per week for at least 13 weeks. In addition, these transplanted patients received fluconazole (200 mg/d) during the first 21 days posttransplant. The prophylaxis-related efficiency and safety were quantified for IFIs and adverse events (AEs) for 6 months after study drug initiation. RESULTS: Prophylaxis was efficient in 59 (98.3%) patients. Only one patient developed a possible IFI, due to Aspergillus fumigatus. Four patients presented nausea and vomiting as an AE, although aerosolized amphotericin B was ongoing. CONCLUSIONS: Nebulized ABLC was effective, safe, and well tolerated for the prophylaxis of aspergillosis in lung transplant patients during the early posttransplant period.


Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Trasplante de Pulmón/efectos adversos , Micosis/prevención & control , Administración por Inhalación , Administración Oral , Adolescente , Adulto , Anciano , Anfotericina B/administración & dosificación , Anfotericina B/efectos adversos , Antifúngicos/administración & dosificación , Antifúngicos/efectos adversos , Aspergilosis/prevención & control , Niño , Femenino , Fluconazol/administración & dosificación , Fluconazol/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Micosis/epidemiología , Náusea/etiología , Estudios Retrospectivos , Factores de Riesgo , Seguridad , Vómitos/etiología , Adulto Joven
18.
BMC Genet ; 8: 11, 2007 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-17408480

RESUMEN

BACKGROUND: Sry is a gene known to be essential for testis determination but is also transcribed in adult male tissues. The laboratory rat, Rattus norvegicus, has multiple Y chromosome copies of Sry while most mammals have only a single copy. DNA sequence comparisons with other rodents with multiple Sry copies are inconsistent in divergence patterns and functionality of the multiple copies. To address hypotheses of divergence, gene conversion and functional constraints, we sequenced Sry loci from a single R. norvegicus Y chromosome from the Spontaneously Hypertensive Rat strain (SHR) and analyzed DNA sequences for homology among copies. Next, to determine whether all copies of Sry are expressed, we developed a modification of the fluorescent marked capillary electrophoresis method to generate three different sized amplification products to identify Sry copies. We applied this fragment analysis method to both genomic DNA and cDNA prepared from mRNA from testis and adrenal gland of adult male rats. RESULTS: Y chromosome fragments were amplified and sequenced using primers that included the entire Sry coding region and flanking sequences. The analysis of these sequences identified six Sry loci on the Y chromosome. These are paralogous copies consistent with a single phylogeny and the divergence between any two copies is less than 2%. All copies have a conserved reading frame and amino acid sequence consistent with function. Fragment analysis of genomic DNA showed close approximations of experimental with predicted values, validating the use of this method to identify proportions of each copy. Using the fragment analysis procedure with cDNA samples showed the Sry copies expressed were significantly different from the genomic distribution (testis p < 0.001, adrenal gland p < 0.001), and the testis and adrenal copy distribution in the transcripts were also significantly different from each other (p < 0.001). Total Sry transcript expression, analyzed by real-time PCR, showed significantly higher levels of Sry in testis than adrenal gland (p, 0.001). CONCLUSION: The SHR Y chromosome contains at least 6 full length copies of the Sry gene. These copies have a conserved coding region and conserved amino acid sequence. The pattern of divergence is not consistent with gene conversion as the mechanism for this conservation. Expression studies show multiple copies expressed in the adult male testis and adrenal glands, with tissue specific differences in expression patterns. Both the DNA sequence analysis and RNA transcript expression analysis are consistent with more than one copy having function and selection preventing divergence although we have no functional evidence.


Asunto(s)
Genes sry , Proteína de la Región Y Determinante del Sexo/genética , Cromosoma Y , Glándulas Suprarrenales/química , Animales , Cartilla de ADN , ADN Complementario , Conversión Génica , Dosificación de Gen , Masculino , Especificidad de Órganos , Ratas , Ratas Endogámicas SHR , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Testículo/química , Transcripción Genética
19.
BMC Cardiovasc Disord ; 7: 6, 2007 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-17324261

RESUMEN

BACKGROUND: Our laboratory has shown that a locus on the SHR Y chromosome increases blood pressure (BP) in the SHR rat and in WKY rats that had the SHR Y chromosome locus crossed into their genome (SHR/y rat). A potential candidate for this Y chromosome hypertension locus is Sry, a gene that encodes a transcription factor that is responsible for testes development and the Sry protein may affect other target genes. METHODS: The following study examined if exogenous Sry would elevate adrenal Th, adrenal catecholamines, plasma catecholamines and blood pressure. We delivered 10 mug of either the expression construct, Sry1/pcDNA 3.1, or control vector into the adrenal medulla of WKY rats by electroporation. Blood pressure was measured by the tail cuff technique and Th and catecholamines by HPLC with electrochemical detection. RESULTS: In the animals receiving Sry there were significant increases after 3 weeks in resting plasma NE (57%) and adrenal Th content (49%) compared to vector controls. BP was 30 mmHg higher in Sry injected animals (160 mmHg, p < .05) compared to vector controls (130 mmHg) after 2-3 weeks. Histological analysis showed that the electroporation procedure did not produce morphological damage. CONCLUSION: These results provide continued support that Sry is a candidate gene for hypertension. Also, these results are consistent with a role for Sry in increasing BP by directly or indirectly activating sympathetic nervous system activity.


Asunto(s)
Médula Suprarrenal/efectos de los fármacos , Médula Suprarrenal/enzimología , Presión Sanguínea/efectos de los fármacos , Proteína de la Región Y Determinante del Sexo/administración & dosificación , Tirosina 3-Monooxigenasa/metabolismo , Médula Suprarrenal/citología , Animales , Electroporación , Técnicas de Transferencia de Gen , Masculino , Norepinefrina/sangre , Ratas , Ratas Endogámicas WKY , Proteína de la Región Y Determinante del Sexo/genética , Proteína de la Región Y Determinante del Sexo/farmacología
20.
Cad. Saúde Pública (Online) ; 38(7): e00286121, 2022. tab, graf
Artículo en Portugués | LILACS | ID: biblio-1394189

RESUMEN

Trata-se de um estudo do tipo caso-controle pareado com o objetivo de verificar a associação entre ocupações e cânceres linfohematopoiéticos em um hospital público de referência no Estado do Ceará, Brasil, durante 2019-2021. O grupo caso foi constituído por pacientes hematológicos que apresentavam mieloma múltiplo, leucemias ou linfomas não Hodgkin, acompanhados pelo serviço social de uma unidade hospitalar de transplante de medula óssea (n = 114), enquanto indivíduos comparáveis de unidade hospitalar distinta constituíram o grupo controle (n = 114), formando pares 1:1. O diagnóstico foi efetuado por equipe médica e as variáveis foram aferidas por acesso aos registros hospitalares. Comparamos os grupos em regressão logística condicional bivariada e ajustada por região de residência. Entre os resultados, destacamos que o câncer de maior prevalência no grupo caso foi o mieloma múltiplo (43,9%), seguido pelas leucemias (43%) e por linfomas não Hodgkin (13,2%). Proporções de ocupações, zona de residência, abastecimento de água e Superintendência Regional de Saúde de residência apresentaram diferença estatisticamente significante entre os grupos caso e controle. Verificamos que trabalhadores rurais possuíam maiores chances de apresentar os cânceres estudados (ORbruto = 5,00, IC95%: 1,91; 13,06 e ORajustado = 3,38, IC95%: 1,20; 9,54), enquanto trabalhadores do comércio apresentaram menores chances (ORbruto = 0,26, IC95%: 0,10; 0,70 e ORajustado = 0,30, IC95%: 0,10; 0,88). Os achados deste estudo possibilitam reflexões sobre o processo de adoecimento dos trabalhadores rurais e refletem o potencial dos serviços de saúde em contribuir com investigações sobre exposições ocupacionais.


This is a paired case-control study that sought to verify the association between professions and lymphohematopoietic cancers in a public reference hospital in the State of Ceará, Brazil, during 2019-2021. Case group consisted of hematological patients with multiple myeloma, leukemias or non-Hodgkin lymphomas, monitored by the social service of a bone marrow transplant hospital unit (n = 114), whereas comparable individuals from a different hospital unit made up the control group (n = 114), forming 1:1 pairs. Diagnosis was performed by a medical team and the variables were measured by accessing hospital records. Group comparison was conducted using bivariate conditional logistic regression and adjusted by region of residence. Results show that multiple myeloma (43.9%), leukemias (43%) and non-Hodgkin lymphomas (13.2%) were the cancer with the highest prevalence in the case group. Proportions of jobs, area of residence, water supply and Regional Superintendence of Health showed statistically significant difference between the case and control groups. Rural workers were more likely to present the cancers studied (ORraw = 5.00, 95%CI: 1.91; 13.06 and ORadjusted = 3.38, 95%CI: 1.20; 9.54), whereas trade workers had lower odds (ORraw = 0.26, 95%CI: 0.10; 0.70 and ORadjusted = 0.30, 95%CI: 0.10; 0.88). The findings allow us to reflect on the process of illness among rural workers and illustrate the potential of health services to contribute to investigations on occupational exposures.


Se trata de un estudio del tipo caso control apareado con el objetivo de verificar la asociación entre ocupaciones y cánceres linfohematopoyéticos en un hospital público de referencia en el estado de Ceará, Brasil, durante el período 2019-2021. El grupo caso estaba formado por pacientes hematológicos que presentaban mieloma múltiple, leucemias o linfomas no Hodgkin, bajo seguimiento por parte del servicio social de una unidad hospitalaria de trasplante de médula ósea (n = 114), mientras que individuos comparables de otra unidad hospitalaria constituyeron el grupo control (n = 114), formando pares 1:1. El diagnóstico fue realizado por un equipo médico, y las variables se midieron accediendo a los registros hospitalarios. Comparamos los grupos en regresión logística condicional bivariada y ajustada por región de residencia. Entre los resultados, destacamos que el cáncer de mayor prevalencia en el grupo caso fue el mieloma múltiple (43,9%), seguido de las leucemias (43%) y los linfomas no Hodgkin (13,2%). Las proporciones de ocupaciones, zona de residencia, abastecimiento de agua y Superintendencia Regional de Salud de residencia presentaron diferencia estadísticamente significativa entre los grupos caso y control. Constatamos que los trabajadores rurales tenían más probabilidades de padecer los cánceres estudiados (ORcrudo = 5,00, IC95%: 1,91; 13,06 y ORajustado = 3,38, IC95%: 1,20; 9,54), mientras que los trabajadores del comercio presentaron menos posibilidades (ORcrudo = 0,26, IC95%: 0,10; 0,70 y ORajustado = 0,30, IC95%: 0,10; 0,88). Los hallazgos de este estudio permiten reflexiones sobre el proceso de enfermedad de los trabajadores rurales y reflejan el potencial de los servicios de salud para contribuir a las investigaciones sobre exposiciones ocupacionales.


Asunto(s)
Humanos , Linfoma no Hodgkin/epidemiología , Leucemia/epidemiología , Mieloma Múltiple/epidemiología , Brasil/epidemiología , Estudios de Casos y Controles , Hospitales
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