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1.
Aquat Toxicol ; 233: 105788, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33662878

RESUMEN

The gene expression response thought to underlie the negative apical effects resulting from estrogen exposure have been thoroughly described in fish. Although epigenetics are believed to play a critical role translating environmental exposures into the development of adverse apical effects, they remain poorly characterized in fish species. This study investigated alterations of DNA methylation of estrogen receptor alpha (esr1) in brain and liver tissues from 8 to 10 month old male fathead minnows (Pimephales promelas) after a 2d exposure to either 2.5 ng/L or 10 ng/L 17α-ethynylestradiol (EE2). Changes in the patterns of methylation were evaluated using targeted deep sequencing of bisulfite treated DNA in the 5' region of esr1. Methylation and gene expression were assessed at 2d of exposure and after a 7 and 14d depuration period. After 2d EE2 exposure, males exhibited significant demethylation in the 5' upstream region of esr1 in liver tissue, which was inversely correlated to gene expression. This methylation pattern reflected what was seen in females. No gene body methylation (GBM) was observed for liver of exposed males. Differential methylation was observed for a single upstream CpG site in the liver after the 14d depuration. A less pronounced methylation response was observed in the upstream region in brain tissue, however, several CpGs were necessarily excluded from the analysis. In contrast to the liver, a significant GBM response was observed across the entire gene body, which was sustained until at least 7d post-exposure. No differential expression was observed in the brain, limiting functional interpretation of methylation changes. The identification of EE2-dependent changes in methylation levels strongly suggests the importance of epigenetic mechanisms as a mediator of the organismal response to environmental exposures and the need for further characterization of the epigenome. Further, differential methylation following depuration indicates estrogenic effects persist well after the active exposure, which has implications for the risk posed by repeated exposures..


Asunto(s)
Cyprinidae/metabolismo , Metilación de ADN/efectos de los fármacos , Receptor alfa de Estrógeno/genética , Etinilestradiol/toxicidad , Expresión Génica/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cyprinidae/genética , Estrógenos/metabolismo , Femenino , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Vitelogeninas/metabolismo
2.
Sci Data ; 6(1): 161, 2019 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-31467271

RESUMEN

Sustained, quantitative observations of nearshore waves and sand levels are essential for testing beach evolution models, but comprehensive datasets are relatively rare. We document beach profiles and concurrent waves monitored at three southern California beaches during 2001-2016. The beaches include offshore reefs, lagoon mouths, hard substrates, and cobble and sandy (medium-grained) sediments. The data span two energetic El Niño winters and four beach nourishments. Quarterly surveys of 165 total cross-shore transects (all sites) at 100 m alongshore spacing were made from the backbeach to 8 m depth. Monthly surveys of the subaerial beach were obtained at alongshore-oriented transects. The resulting dataset consists of (1) raw sand elevation data, (2) gridded elevations, (3) interpolated elevation maps with error estimates, (4) beach widths, subaerial and total sand volumes, (5) locations of hard substrate and beach nourishments, (6) water levels from a NOAA tide gauge (7) wave conditions from a buoy-driven regional wave model, and (8) time periods and reaches with alongshore uniform bathymetry, suitable for testing 1-dimensional beach profile change models.

3.
Thromb Res ; 179: 132-139, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31132667

RESUMEN

OBJECTIVE: Specific protocols for anticoagulation for children on ECMO vary across institutions, with most using a continuous infusion of unfractionated heparin. The goal of this study is to aid clinician's decision on the best measure of heparin anticoagulation test; which would be the one that correlates well with heparin activity and helps in predicting hemorrhagic and thrombotic complications. DATA SOURCES: A comprehensive search of MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and Scopus was conducted from each database's inception to 07/13/2018. STUDY SELECTION: Studies evaluating children (<18 years) treated with ECMO and evaluating ACT, aPTT, TEG and Anti-Xa in any language were included. DATA EXTRACTION: Two reviewers selected and appraised studies independently, and abstracted data. RESULTS: We included 19 studies (759 patients, mean age 19.8 months). Meta-analysis showed strong correlation between heparin dosing and anti-Xa. Additionally, there was not a strong correlation between laboratory tests and complications (hemorrhagic and thrombosis), or mortality. CONCLUSION: Based on current evidence, Anti-Xa is the only laboratory test that shows strong correlation with heparin infusion dose and seems like the most suitable test for monitoring of anticoagulation with heparin in children on ECMO.


Asunto(s)
Anticoagulantes/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Adolescente , Anticoagulantes/farmacología , Niño , Preescolar , Oxigenación por Membrana Extracorpórea , Femenino , Heparina de Bajo-Peso-Molecular/farmacología , Humanos , Lactante , Masculino
4.
Int J Tuberc Lung Dis ; 20(8): 1046-54, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27393538

RESUMEN

SETTING: Tuberculosis (TB) is a leading cause of childhood death. Patient-level data on pediatric TB in Malawi that can be used to guide programmatic interventions are limited. OBJECTIVE: To describe pediatric TB case burden, disease patterns, treatment outcomes, and risk factors for death and poor outcome. DESIGN: We conducted a retrospective cohort study utilizing routine data. Odds ratios (ORs) for factors associated with poor outcome and death were calculated using generalized estimating equations. RESULTS: Children represented 8% (371/4642) of TB diagnoses. The median age was 7 years (interquartile range 2.8-11); 32.8% (113/345) were human immunodeficiency virus (HIV) infected. Of these, 54.0% were on antiretroviral therapy (ART) at the time of anti-tuberculosis treatment (ATT) initiation, 21.2% started ART during ATT, and 24.8% had no documented ART. The treatment success rate was 77.3% (11.2% cured, 66.1% completed treatment), with 22.7% experiencing poor outcomes (9.5% died, 13.2% were lost to follow-up). Being on ART at the time of ATT initiation was associated with increased odds of death compared to beginning ART during treatment (adjusted OR 2.75, 95%CI 1.27-5.96). CONCLUSION: Children represent a small proportion of diagnosed TB cases and experience poor outcomes. Higher odds of death among children already on ART raises concerns over the management of these children. Further discussion of and research into pediatric-specific strategies is required to improve case finding and outcomes.


Asunto(s)
Antituberculosos/uso terapéutico , Tuberculosis/tratamiento farmacológico , Tuberculosis/mortalidad , Adolescente , Factores de Edad , Antirretrovirales/uso terapéutico , Causas de Muerte , Distribución de Chi-Cuadrado , Niño , Preescolar , Coinfección , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Humanos , Lactante , Estimación de Kaplan-Meier , Malaui/epidemiología , Masculino , Análisis Multivariante , Oportunidad Relativa , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Tuberculosis/diagnóstico
5.
J Bacteriol ; 197(4): 749-61, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25488301

RESUMEN

CRISPR-Cas systems provide adaptive microbial immunity against invading viruses and plasmids. The cariogenic bacterium Streptococcus mutans UA159 has two CRISPR-Cas systems: CRISPR1 (type II-A) and CRISPR2 (type I-C) with several spacers from both CRISPR cassettes matching sequences of phage M102 or genomic sequences of other S. mutans. The deletion of the cas genes of CRISPR1 (ΔC1S), CRISPR2 (ΔC2E), or both CRISPR1+2 (ΔC1SC2E) or the removal of spacers 2 and 3 (ΔCR1SP13E) in S. mutans UA159 did not affect phage sensitivity when challenged with virulent phage M102. Using plasmid transformation experiments, we demonstrated that the CRISPR1-Cas system inhibits transformation of S. mutans by the plasmids matching the spacers 2 and 3. Functional analysis of the cas deletion mutants revealed that in addition to a role in plasmid targeting, both CRISPR systems also contribute to the regulation of bacterial physiology in S. mutans. Compared to wild-type cells, the ΔC1S strain displayed diminished growth under cell membrane and oxidative stress, enhanced growth under low pH, and had reduced survival under heat shock and DNA-damaging conditions, whereas the ΔC2E strain exhibited increased sensitivity to heat shock. Transcriptional analysis revealed that the two-component signal transduction system VicR/K differentially modulates expression of cas genes within CRISPR-Cas systems, suggesting that VicR/K might coordinate the expression of two CRISPR-Cas systems. Collectively, we provide in vivo evidence that the type II-A CRISPR-Cas system of S. mutans may be targeted to manipulate its stress response and to influence the host to control the uptake and dissemination of antibiotic resistance genes.


Asunto(s)
Proteínas Bacterianas/inmunología , Proteínas Asociadas a CRISPR/inmunología , Sistemas CRISPR-Cas , Streptococcus mutans/inmunología , Proteínas Bacterianas/genética , Bacteriófagos/fisiología , Proteínas Asociadas a CRISPR/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Viabilidad Microbiana , Streptococcus mutans/genética , Streptococcus mutans/crecimiento & desarrollo , Streptococcus mutans/virología
6.
Zoonoses Public Health ; 59 Suppl 2: 142-50, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22958258

RESUMEN

Rift Valley fever virus (RVFV) is an arbovirus that causes significant morbidity and mortality in both humans and livestock. With increased world travel and the threat of bioterrorism, there is a real risk of RVFV spreading to naïve geographical areas (Trans. R. Soc. Trop. Med. Hyg., 73, 1979, 618; MMWR Morb. Mortal. Wkly Rep., 49, 2000, 905). The introduction of RVFV would cause critical public health, agricultural and economic damage. Despite the clear need for an efficacious vaccine, there are no United States (US) Food and Drug Administration or US Department of Agriculture approved vaccines against RVFV. To address this need, a virus-like particle (VLP)-based vaccine candidate was developed. First, a non-replicating chimeric RVF VLP vaccine candidate was generated that protected mice and rats against a lethal RVFV challenge. This was followed by the development and optimization of conditions for production of RVF VLPs in insect and mammalian cells. Immunological studies demonstrated that VLP-based vaccine candidates elicit both humoral and cellular immune responses. Subsequent challenge studies using a lethal wild-type RVFV strain under high-containment conditions showed that RVF VLP vaccine candidates can completely protect mice and rats.


Asunto(s)
Fiebre del Valle del Rift/prevención & control , Virus de la Fiebre del Valle del Rift/inmunología , Vacunas de Partículas Similares a Virus/inmunología , Vacunas Virales/inmunología , Animales , Ratones , Ratas , Zoonosis
7.
Neuropharmacology ; 63(6): 1051-63, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22796107

RESUMEN

Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERß, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERß can regulate ERα activity. Moreover, ERß knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERß-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERß in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken together these data suggest that ERß may play an important role in modulating mood and the ERß specific compounds described herein will be useful tools for probing the utility of an ERß agonist for treating neuroendocrine-related mood disturbance and menopausal symptoms.


Asunto(s)
Antidepresivos , Receptor beta de Estrógeno/efectos de los fármacos , ARN Mensajero/biosíntesis , Núcleos del Rafe/enzimología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Natación/psicología , Triptófano Hidroxilasa/biosíntesis , Animales , Barrera Hematoencefálica/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ADN/genética , Relación Dosis-Respuesta a Droga , Receptor alfa de Estrógeno/efectos de los fármacos , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/crecimiento & desarrollo , Humanos , Inmunohistoquímica , Hibridación in Situ , Neurogénesis/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Plásmidos/genética , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Receptores Androgénicos/metabolismo , Receptores de Progesterona/metabolismo , Activación Transcripcional/efectos de los fármacos , Triptófano Hidroxilasa/genética , Útero/anatomía & histología , Útero/fisiología
8.
Zoonoses Public Health ; 56(6-7): 391-406, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19486321

RESUMEN

The αGal HyperAcute(®) Technology exploits a robust zoonotic blockade to enhance potency of antiviral vaccines. Naturally acquired immunity against the common αGal epitope [galactose-alpha(1,3)-galactose-beta(1,4)N-acetylglucosamine-R (Gal-α(1,3)-Gal-ß(1,4)-GlcNAc-R)] is facilitated by the loss of a key enzyme in the epitope's biosynthetic pathway. As human cells are devoid of this epitope, chronic stimulus from gut flora leads to high levels of circulating anti-αGal antibodies and the development of a robust immune pathway. As the αGal epitope is immediately recognized as foreign, the naturally acquired αGal immune pathway in humans serves as a strong barrier to zoonotic infection. The αGal HyperAcute(®) Technology takes advantage of this natural process to facilitate the rapid presentation of modified antigens to antigen-presenting cells, leading to a strong immune response. The evolutionary immunity to αGal ensures that the presence of αGal epitopes on antigens will lead to a robust immune response involving cross-activation of T(H)1 immunity, characterized by cytokine secretion and increased phagocytic activity, and T(H)2 immunity characterized by high antibody titres. αGal epitopes can be applied to antiviral vaccines by biological, enzymatic or chemical means. Several detection methods that directly and indirectly verify αGal addition are discussed. Enhanced immunogenicity (humoral and cellular) of αGal-modified vaccines is shown for several antiviral vaccine candidates. αGal modification of antiviral vaccine components leads to enhanced immunogenicity. The existing body of literature describing the utility of αGal epitopes as a safe and robust immunostimulatory and -modulatory agent in humans supports the basis for applying the αGal HyperAcute(®) Technology to the improvement of antiviral vaccines, both new and currently approved.


Asunto(s)
Galactosiltransferasas/inmunología , Galactosiltransferasas/metabolismo , Vacunas Virales/inmunología , Adyuvantes Inmunológicos , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Células Cultivadas , Epítopos/metabolismo , Humanos , Vacunación , Zoonosis
9.
Mol Psychiatry ; 13(5): 498-506, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17622221

RESUMEN

Considerable attention has focused on regulation of central tryptophan hydroxylase (TPH) activity and protein expression. At the time of these earlier studies, it was thought that there was a single central TPH isoform. However, with the recent identification of TPH2, it becomes important to distinguish between regulatory effects on the protein expression and activity of the two isoforms. We have generated a TPH2-specific polyclonal antiserum (TPH2-6361) to study regulation of TPH2 at the protein level and to examine the distribution of TPH2 expression in rodent and human brain. TPH2 immunoreactivity (IR) was detected throughout the raphe nuclei, in lateral hypothalamic nuclei and in the pineal body of rodent and human brain. In addition, a prominent TPH2-IR fiber network was found in the human median eminence. We recently reported that glucocorticoid treatment of C57/Bl6 mice for 4 days markedly decreased TPH2 messenger RNA levels in the raphe nuclei, whereas TPH1 mRNA was unaffected. The glucocorticoid-elicited inhibition of TPH2 gene expression was blocked by co-administration of the glucocorticoid receptor antagonist mifepristone (RU-486). Using TPH2-6361, we have extended these findings to show a dose-dependent decrease in raphe TPH2 protein levels in response to 4 days of treatment with dexamethasone; this effect was blocked by co-administration of mifepristone. Moreover, the glucocorticoid-elicited inhibition of TPH2 was functionally significant: serotonin synthesis was significantly reduced in the frontal cortex of glucocorticoid-treated mice, an effect that was blocked by mifepristone co-administration. This study provides further evidence for the glucocorticoid regulation of serotonin biosynthesis via inhibition of TPH2 expression, and suggest that elevated glucocorticoid levels may be relevant to the etiology of psychiatric diseases, such as depression, where hypothalamic-pituitary-adrenal axis dysregulation has been documented.


Asunto(s)
5-Hidroxitriptófano/biosíntesis , Dexametasona/análogos & derivados , Lóbulo Frontal/química , Proteínas del Tejido Nervioso/biosíntesis , Núcleos del Rafe/enzimología , Triptófano Hidroxilasa/análisis , Triptófano Hidroxilasa/biosíntesis , 5-Hidroxitriptófano/análisis , Secuencia de Aminoácidos , Animales , Especificidad de Anticuerpos , Dexametasona/farmacología , Inducción Enzimática/efectos de los fármacos , Femenino , Lóbulo Frontal/efectos de los fármacos , Humanos , Sueros Inmunes , Ratones , Ratones Endogámicos C57BL , Mifepristona/farmacología , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Ovariectomía , Fragmentos de Péptidos/inmunología , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , ARN Mensajero/biosíntesis , Núcleos del Rafe/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Triptófano Hidroxilasa/genética , Triptófano Hidroxilasa/inmunología
10.
Transgenic Res ; 13(6): 531-40, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15672834

RESUMEN

Previous studies have shown that depletion of cardiac actin by targeted disruption is associated with increased expression of alternative actins in the mouse heart. Here we have studied the effects of transgenic overexpression of cardiac actin using the alpha-myosin heavy chain promoter. Lines carrying 7 or 8 copies of the transgene showed a 2-fold increase in cardiac actin mRNA and also displayed decreased expression of skeletal and vascular actin in their hearts. In contrast, a line with more than 250 copies of the transgene did not show a similar decrease in the expression of skeletal and vascular actin despite a 3-fold increase in cardiac actin mRNA. While the low copy number transgenic mice displayed hearts that were similar to non-transgenic controls, the high copy number transgenic line showed larger hearts with distinct atrial enlargement and cardiomyocyte hypertrophy. Further, while the low copy number transgenic mouse hearts were mildly hypocontractile when compared with non-transgenic mouse hearts, the high copy number transgenic mouse hearts were significantly so. We conclude that in the presence of a small number of copies of the cardiac actin transgene, homeostatic mechanisms involved in maintaining actin levels are active and negatively regulate skeletal and vascular actin levels in the heart in response to increased expression of cardiac actin. However, these putative mechanisms are either inoperative in the high copy number transgenic line or are countered by the enhanced expression of skeletal and vascular actin during cardiomyocyte hypertrophy.


Asunto(s)
Actinas/metabolismo , Cardiomegalia/etiología , Regulación de la Expresión Génica , Miocardio/metabolismo , Actinas/genética , Actinas/ultraestructura , Animales , Cardiomegalia/genética , Cardiomegalia/patología , Dosificación de Gen , Ratones , Ratones Transgénicos , Músculo Esquelético/metabolismo , Contracción Miocárdica/genética , Miocardio/patología , Miocardio/ultraestructura , Cadenas Pesadas de Miosina/genética , Tamaño de los Órganos , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo
11.
Mol Cell Biol ; 22(16): 5887-96, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12138199

RESUMEN

All four of the muscle actins (skeletal, cardiac, vascular, and enteric) in higher vertebrates show distinct expression patterns and display highly conserved amino acid sequences. While it is hypothesized that each of the muscle isoactins is specifically adapted to its respective tissue and that the minor variations among them have developmental and/or physiological relevance, the exact functional and developmental significance of these proteins remains largely unknown. In order to begin to assess these issues, we disrupted the skeletal actin gene by homologous recombination. All mice lacking skeletal actin die in the early neonatal period (day 1 to 9). These null animals appear normal at birth and can breathe, walk, and suckle, but within 4 days, they show a markedly lower body weight than normal littermates and many develop scoliosis. Null mice show a loss of glycogen and reduced brown fat that is consistent with malnutrition leading to death. Newborn skeletal muscles from null mice are similar to those of wild-type mice in size, fiber type, and ultrastructural organization. At birth, both hemizygous and homozygous null animals show an increase in cardiac and vascular actin mRNA in skeletal muscle, with no skeletal actin mRNA present in null mice. Adult hemizygous animals show an increased level of skeletal actin mRNA in hind limb muscle but no overt phenotype. Extensor digitorum longus (EDL) muscle isolated from skeletal-actin-deficient mice at day 2 to 3 showed a marked reduction in force production compared to that of control littermates, and EDL muscle from hemizygous animals displayed an intermediate force generation. Thus, while increases in cardiac and vascular smooth-muscle actin can partially compensate for the lack of skeletal actin in null mice, this is not sufficient to support adequate skeletal muscle growth and/or function.


Asunto(s)
Actinas/genética , Actinas/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/fisiología , Animales , Animales Recién Nacidos , Marcación de Gen , Humanos , Ratones , Ratones Noqueados , Músculo Esquelético/ultraestructura , Fenotipo , Isoformas de Proteínas , Células Madre/fisiología
12.
Virology ; 289(2): 400-10, 2001 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-11689061

RESUMEN

While influenza A viral RNA is known to act as a template for the synthesis of both viral mRNA and complementary cRNA, the latter has been observed so far only to function as an intermediate in replication and give rise to progeny vRNA molecules. Here it is shown that the cRNA promoter is also capable of initiating viral mRNA synthesis, similar to vRNA-promoted transcription adhering to the cap-snatching mode of primer recruitment. Detection of cRNA promoted transcription required an inversion of the reporter gene coding sequence plus relocation of the viral polyadenylation signal. Construction of cRNA promoter variants through RNA polymerase I reverse genetics allowed us to determine the RNA polymerase-associated, base-paired conformation in a reporter gene read-out system. It again turned out to adhere to the "corkscrew" model, similar, but slightly different in its binding interactions from the corresponding vRNA conformation. The observation of two transcription reactions, initiated in either direction from influenza vRNA and cRNA template molecules, allowed us to construct bicistronic, ambisense RNA molecules for simultaneous expression of two proteins from a single segment of viral RNA.


Asunto(s)
Virus de la Influenza A/fisiología , Regiones Promotoras Genéticas/fisiología , ARN Viral/fisiología , Línea Celular , ARN Complementario/genética , ARN Mensajero/genética , ARN Viral/genética , Moldes Genéticos , Transcripción Genética , Replicación Viral/genética
13.
RNA ; 7(7): 979-89, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11453070

RESUMEN

The packaging signal present in influenza viral RNA molecules is shown not to constitute a separate structural element, but to reside within the 5'-bulged promoter structure, as caused by the central unpaired residue A10 in its 5' branch. Upon insertion of two uridine residues in the 3' branch opposite A10, the minus-strand viral RNA (vRNA) promoter is converted into a 3'-bulged structure, whereas the plus-strand cRNA promoter instead adopts the 5'-bulged conformation. In this promoter variant it is exclusively the cRNA that is found packaged in the progeny virions. Upon insertion of only a single uridine nucleotide opposite 5'A10, the two debulged structures of the vRNA and cRNA promoters are rendered identical, and both vRNA and cRNA molecules are packaged indiscriminately, in a 1:1 ratio, but at lower rates. We propose that the binding interactions of viral polymerase with either of the two differently bulged vRNA and cRNA promoter structures result in two different conformations of the enzyme protein. Only the 5' bulged RNA-associated polymerase conformation appears to be recognized for nuclear export, which depends on nuclear matrix protein M1 and nonstructural protein NS2. And the respective wild-type vRNP- or insertion mutant cRNP complex is observed to enter the cytoplasm and hence is included in the viral encapsidation process, which takes place at the plasma membrane.


Asunto(s)
Orthomyxoviridae/genética , ARN Viral/metabolismo , Ensamble de Virus , Animales , Secuencia de Bases , Línea Celular , Cloranfenicol O-Acetiltransferasa/genética , Cartilla de ADN , Ratones , Conformación de Ácido Nucleico , Regiones Promotoras Genéticas , ARN Viral/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribonucleoproteínas/metabolismo
15.
J Virol ; 75(4): 1643-55, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11160662

RESUMEN

We describe here the development of a reverse genetics system for the phlebovirus Uukuniemi virus, a member of the Bunyaviridae family, by using RNA polymerase I (pol I)-mediated transcription. Complementary DNAs containing the coding sequence for either chloramphenicol acetyltransferase (CAT) or green fluorescent protein (GFP) (both in antisense orientation) were flanked by the 5'- and 3'-terminal untranslated regions of the Uukuniemi virus sense or complementary RNA derived from the medium-sized (M) RNA segment. This chimeric cDNA (pol I expression cassette) was cloned between the murine pol I promoter and terminator and the plasmid transfected into BHK-21 cells. When such cells were either superinfected with Uukuniemi virus or cotransfected with expression plasmids encoding the L (RNA polymerase), N (nucleoprotein), and NSs (nonstructural protein) viral proteins, strong CAT activity or GFP expression was observed. CAT activity was consistently stronger in cells expressing L plus N than following superinfection. No activity was seen without superinfection, nor was activity detected when either the L or N expression plasmid was omitted. Omitting NSs expression had no effect on CAT activity or GFP expression, indicating that this protein is not needed for viral RNA replication or transcription. CAT activity could be serially passaged to fresh cultures by transferring medium from CAT-expressing cells, indicating that recombinant virus containing the reporter construct had been produced. In summary, we demonstrate that the RNA pol I system, originally developed for influenza virus, which replicates in the nucleus, has strong potential for the development of an efficient reverse genetics system also for Bunyaviridae members, which replicate in the cytoplasm.


Asunto(s)
Infecciones por Bunyaviridae/virología , ARN Polimerasa I/metabolismo , Transcripción Genética , Virus Uukuniemi/genética , Animales , Secuencia de Bases , Línea Celular , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Cricetinae , ADN Complementario/genética , Genes Reporteros/genética , Genes Reporteros/fisiología , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Datos de Secuencia Molecular , Plásmidos/genética , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transfección , Virus Uukuniemi/metabolismo
16.
J Neurosurg Anesthesiol ; 12(2): 107-11, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10774604

RESUMEN

We report the numerous management challenges surrounding the care of a child in whom bilateral thalamotomies were used to treat end-stage Hallervorden-Spatz Disease (HSD). The management of this patient was greatly facilitated by the use of modern anesthetic agents and a multidisciplinary team to care for the patient. The outcome was an improved life expectancy and quality of life.


Asunto(s)
Anestesia , Neurodegeneración Asociada a Pantotenato Quinasa/cirugía , Tálamo/cirugía , Terapia Asistida por Computador , Niño , Potenciales Evocados , Femenino , Humanos , Monitoreo Intraoperatorio , Procedimientos Neuroquirúrgicos , Grupo de Atención al Paciente , Medicación Preanestésica , Técnicas Estereotáxicas , Resultado del Tratamiento
17.
Kidney Int ; 57(1): 293-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10620211

RESUMEN

UNLABELLED: A trial of thyroxine in acute renal failure. BACKGROUND: Acute renal failure (ARF) remains a serious medical problem with a high mortality rate. Efforts to shorten the course of ARF might reduce this mortality. Since thyroxine has been shown in experimental models to shorten the course of ARF, we designed a trial to determine if a defined course of thyroxine would alter the course or change the mortality of clinical ARF. METHODS: A prospective, randomized, placebo-controlled, double-blind trial of thyroxine was carried out in patients with ARF. End points were the percentage requiring dialysis, the percentage recovering renal function, time to recovery, and mortality. RESULTS: Fifty-nine patients were randomized to receive either thyroxine or placebo. The groups were well matched in terms of basal and entry creatinines, age, sex, APACHE II scores at entry, and percentage oliguric. Baseline thyroid functions, including T3, T4, rT3, and thyroid stimulating hormone (TSH) levels, were equal between the two groups and typical of patients with euthyroid sick syndrome. Thyroxine resulted in a progressive and sustained suppression of TSH levels in the treated group, but had no effect on any measure of ARF severity. Mortality was higher in the thyroxine group than the control group (43 vs. 13%) and correlated with suppression of TSH. CONCLUSIONS: In contrast to the beneficial effects seen in experimental ARF, thyroxine has no effect on the course of clinical ARF and could have a negative effect on outcome through prolonged suppression of TSH. Critically ill euthyroid sick patients should not be replaced with thyroid hormone.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Tiroxina/uso terapéutico , APACHE , Lesión Renal Aguda/patología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
Virology ; 262(1): 93-103, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10489344

RESUMEN

The 5'- and 3'-terminal regions of influenza vRNA molecules are known to constitute the promoter structure upon association with viral RNA polymerase in an activated complementary conformation. An inherent requirement for their location at the very ends of the vRNA molecules always has been implied because of that natural structure, but this study demonstrates that one or both of the promoter sequences may be relocated into vRNA-internal positions and still retain their polymerase-binding function. External extensions of vRNA molecules employed include either single-stranded RNA sequences

Asunto(s)
Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , ARN Viral/genética , ARN/genética , Regiones no Traducidas 3'/genética , Regiones no Traducidas 5'/genética , Animales , Perros , Amplificación de Genes , Conformación de Ácido Nucleico , Regiones Promotoras Genéticas/genética , Empalme del ARN/genética , ARN Complementario/genética , ARN Mensajero/genética , Análisis de Secuencia de ARN , Replicación Viral/genética
20.
J Reprod Med ; 44(2): 127-30, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10853444

RESUMEN

BACKGROUND: Diaphragmatic rupture may be easily overlooked at the time of multiple trauma. Occult diaphragmatic rupture may first manifest during pregnancy as severe dyspnea. CASE: A parous woman who had sustained multiple traumatic injuries prior to pregnancy presented in midtrimester with abdominal pain and dyspnea. Chest roentgenography and computed tomography revealed bowel in the left hemithorax, compatible with a left-sided diaphragmatic rupture. Surgical correction was indicated secondary to the symptomatic nature of the presentation. CONCLUSION: Diaphragmatic rupture may be occult and may first present during a subsequent pregnancy. Surgical therapy is the cornerstone of management when a diaphragmatic defect is symptomatic. The route of delivery may be individualized for patients with diaphragmatic repairs in whom there has been sufficient time for healing.


Asunto(s)
Diafragma/lesiones , Hernia Diafragmática Traumática/cirugía , Complicaciones del Embarazo/cirugía , Adolescente , Femenino , Humanos , Embarazo , Rotura
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