Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 186
Filtrar
Más filtros

Intervalo de año de publicación
1.
Environ Res ; 239(Pt 1): 117281, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37827370

RESUMEN

Lanthanides are indispensable constituents of modern technologies and are often challenging to acquire from natural resources. The demand for REEs is so high that there is a clear need to develop efficient and eco-friendly recycling methods. In the present study, freeze-dried biomass of the polyextremophile Galdieria sulphuraria was employed to recover REEs from spent fluorescent lamps (FL) luminophores by pretreating the freeze-dried biomass with an acid solution to favour ion exchange and enhance the binding sites on the cell surface available for the metal ions. Lanthanides were extracted from the luminophores using sulfuric acid solutions according to standardised procedures, and the effect of biosorbent dosage (0.5-5 mg/ml) and biosorption time (5-60 min) were evaluated. The content of individual REEs in the luminophores and the resulting algal biomass were determined using inductively coupled plasma mass spectrometry (ICP-MS). The most abundant REE in the luminophores was yttrium (287.42 mg/g dm, 91.60% of all REEs), followed by europium (20.98 mg/g, 6.69%); cerium, gadolinium, terbium and lanthanum was in trace. The best biosorption performances were achieved after 5 min and at the lowest biosorbent dosage (0.5 mg/mL). The highest total metal amount corresponded to 41.61 mg/g dried mass, and yttrium was the most adsorbed metal (34.59 mg/g dm, 82.88%), followed by cerium (4.01 mg/g); all other metals were less than 2 mg/g. The rapidity of the biosorption process and the low biosorbent dosage required confirmed this microalga as a promising material for creating an eco-sustainable protocol for recycling REEs.


Asunto(s)
Cerio , Metales de Tierras Raras , Rhodophyta , Metales de Tierras Raras/análisis , Itrio , Metales/metabolismo , Rhodophyta/metabolismo
2.
Anim Genet ; 52(1): 32-46, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33191532

RESUMEN

This study aimed to assess the predictive ability of different machine learning (ML) methods for genomic prediction of reproductive traits in Nellore cattle. The studied traits were age at first calving (AFC), scrotal circumference (SC), early pregnancy (EP) and stayability (STAY). The numbers of genotyped animals and SNP markers available were 2342 and 321 419 (AFC), 4671 and 309 486 (SC), 2681 and 319 619 (STAY) and 3356 and 319 108 (EP). Predictive ability of support vector regression (SVR), Bayesian regularized artificial neural network (BRANN) and random forest (RF) were compared with results obtained using parametric models (genomic best linear unbiased predictor, GBLUP, and Bayesian least absolute shrinkage and selection operator, BLASSO). A 5-fold cross-validation strategy was performed and the average prediction accuracy (ACC) and mean squared errors (MSE) were computed. The ACC was defined as the linear correlation between predicted and observed breeding values for categorical traits (EP and STAY) and as the correlation between predicted and observed adjusted phenotypes divided by the square root of the estimated heritability for continuous traits (AFC and SC). The average ACC varied from low to moderate depending on the trait and model under consideration, ranging between 0.56 and 0.63 (AFC), 0.27 and 0.36 (SC), 0.57 and 0.67 (EP), and 0.52 and 0.62 (STAY). SVR provided slightly better accuracies than the parametric models for all traits, increasing the prediction accuracy for AFC to around 6.3 and 4.8% compared with GBLUP and BLASSO respectively. Likewise, there was an increase of 8.3% for SC, 4.5% for EP and 4.8% for STAY, comparing SVR with both GBLUP and BLASSO. In contrast, the RF and BRANN did not present competitive predictive ability compared with the parametric models. The results indicate that SVR is a suitable method for genome-enabled prediction of reproductive traits in Nellore cattle. Further, the optimal kernel bandwidth parameter in the SVR model was trait-dependent, thus, a fine-tuning for this hyper-parameter in the training phase is crucial.


Asunto(s)
Bovinos/genética , Aprendizaje Automático , Modelos Genéticos , Reproducción/genética , Animales , Brasil , Femenino , Genómica , Fenotipo , Polimorfismo de Nucleótido Simple , Embarazo
3.
Lett Appl Microbiol ; 73(2): 139-148, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33843058

RESUMEN

Infections caused by KPC-producing Klebsiella pneumoniae (Kp-KPC) are associated with high mortality rates due to the increased number of resistant isolates and the scarcity of therapeutic options. This scenario reinforces the urgent need for new chemotherapeutics. Herein, we investigated the effects of 1,10-phenanthroline-5,6-dione (phendione) and its metal-based complexes, [Cu(phendione)3 ](ClO4 )2 .4H2 O (Cu-phendione) and [Ag(phendione)2 ]ClO4 (Ag-phendione), both alone and also combined with carbapenems (meropenem (MEM), and imipenem), against 46 clonally distinct clinical strains of Kp-KPC. All isolates were found to be multidrug resistant in accordance with their susceptibility patterns by disk diffusion method. Compounds geometric mean (GM)-MIC and GM-MBC values (µmol l-1 ), respectively, were: phendione, 42·06 and 71·27; Cu-phendione, 9·88 and 13·75; and Ag-phendione, 10·10 and 13·06. Higher synergism rates of MEM-containing combinations were observed by the checkerboard assay, particularly with the two metal complexes. Moreover, drug combinations were able to re-sensitize 87% of the phenotypically non-susceptible strains. Time-kill studies, with MEM plus Cu-phendione or Ag-phendione, indicated that combinations with 0·5× MIC of each agent produce synergistic effects after 9-12 h. The MEM plus Ag-phendione eradicated about 106  CFU per ml of bacteria. These findings support the effectiveness of the re-sensitizing combinatorial approach and provide evidence that phendione-based compounds offer real promise in the fight against Kp-KPC infections.


Asunto(s)
Carbapenémicos/farmacología , Complejos de Coordinación/farmacología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Fenantrolinas/farmacología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Farmacorresistencia Bacteriana Múltiple , Sinergismo Farmacológico , Humanos , Imipenem/farmacología , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , beta-Lactamasas/farmacología
4.
J Hum Evol ; 130: 126-140, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31010539

RESUMEN

Fundamental disagreements remain regarding the relative importance of climate change and human activities as triggers for Madagascar's Holocene megafaunal extinction. We use stable isotope data from stalagmites from northwest Madagascar coupled with radiocarbon and butchery records from subfossil bones across the island to investigate relationships between megafaunal decline, climate change, and habitat modification. Archaeological and genetic evidence support human presence by 2000 years Before Common Era (BCE). Megafaunal decline was at first slow; it hastened at ∼700 Common Era (CE) and peaked between 750 and 850 CE, just before a dramatic vegetation transformation in the northwest that resulted in the replacement of C3 woodland habitat with C4 grasslands, during a period of heightened monsoonal activity. Cut and chop marks on subfossil lemur bones reveal a shift in primary hunting targets from larger, now-extinct species prior to ∼900 CE, to smaller, still-extant species afterwards. By 1050 CE, megafaunal populations had essentially collapsed. Neither the rapid megafaunal decline beginning ∼700 CE, nor the dramatic vegetation transformation in the northwest beginning ∼890 CE, was influenced by aridification. However, both roughly coincide with a major transition in human subsistence on the island from hunting/foraging to herding/farming. We offer a new hypothesis, which we call the "Subsistence Shift Hypothesis," to explain megafaunal decline and extinction in Madagascar. This hypothesis acknowledges the importance of wild-animal hunting by early hunter/foragers, but more critically highlights negative impacts of the shift from hunting/foraging to herding/farming, settlement by new immigrant groups, and the concomitant expansion of the island's human population. The interval between 700 and 900 CE, when the pace of megafaunal decline quickened and peaked, coincided with this economic transition. While early megafaunal decline through hunting may have helped to trigger the transition, there is strong evidence that the economic shift itself hastened the crash of megafaunal populations.


Asunto(s)
Agricultura , Extinción Biológica , Mamíferos , Paleognatos , Animales , Arqueología , Biodiversidad , Ecosistema , Humanos , Madagascar
5.
Genet Mol Res ; 15(4)2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27966739

RESUMEN

This study aimed to investigate the predictability of a phenotype when using a dynamic model of cattle growth. Genotypic and phenotypic information on Nellore (Bos indicus) cattle were used in a genome-wide association analysis designed to contrast the biological interpretation of core parameters [conversion efficiency of metabolizable energy to net energy for gain (kg) and adjusted final shrunk body weight (AFSBW)] to their associated genomic regions and nearby quantitative trait loci (QTLs). Single nucleotide polymorphisms (SNPs) were used to develop prediction equations for kg and AFSBW, which enter the model for simulative prediction purposes. QTLs and genes, one related to mature body weight and another to growth efficiency, are consistent with the model equations. Significantly associated SNPs were used to compute parameters, which yielded reasonable model outcomes when compared with regular parameter computations. Our results provide evidence of the biological validity of using such parameters as component traits of higher phenotypes and the possibility of using genomic data for genotype-to-parameter mapping.


Asunto(s)
Peso Corporal/genética , Modelos Biológicos , Sitios de Carácter Cuantitativo , Animales , Bovinos , Estudio de Asociación del Genoma Completo , Genotipo , Fenotipo , Polimorfismo de Nucleótido Simple
6.
Reprod Domest Anim ; 51(5): 819-26, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27554760

RESUMEN

Haematological metabolic profiles in heifers could contribute to the development of proxies for oestrous detection and provide clues to further characterize biological changes during oestrus. One hundred and seven beef heifers were observed for oestrous behaviour twice daily for 124 days. Feed intake and productive performance (body weight and composition) traits were measured, and feed efficiency was determined using residual feed intake (kg DM/day). Blood plasma samples were collected when signs of oestrus were observed and every 30 ± 2 days. Heifers were considered in oestrus (n = 71) when plasma progesterone concentrations were <0.6 ng/ml. Least square means of blood metabolic parameters were compared between oestrous and non-oestrous states and within oestrous groups according to performance traits and age. Heifers in oestrus exhibited higher concentrations of alkaline phosphatase, aspartate aminotransferase (AST), beta-hydroxybutyric acid, creatine kinase (CK) and triiodothyronine (T3) than heifers in non-oestrus. Heifers in oestrus revealed lower osmolality and concentrations of calcium, sodium and total protein than during non-oestrus. Younger (and smaller) heifers had greater concentrations of CK, gamma-glutamyl transferase (GGT), glucose and sodium than the older heifers. Heifers with lower fatness had increased osmolality and concentrations of cholesterol, CK, phosphorus, sodium and reduced T3 levels. Feed efficient heifers had greater levels of AST, cholesterol and GGT than inefficient heifers. Blood plasma parameters may be complementary to oestrous detection upon further validation; effects of age, feed efficiency, body size and body composition should be considered to optimize this haematological assessment.


Asunto(s)
Bovinos/sangre , Bovinos/metabolismo , Estro/sangre , Estro/metabolismo , Ácido 3-Hidroxibutírico/sangre , Tejido Adiposo , Envejecimiento , Fosfatasa Alcalina/sangre , Animales , Aspartato Aminotransferasas/sangre , Composición Corporal , Creatina Quinasa/sangre , Progesterona/sangre , Triyodotironina/sangre
7.
Genet Mol Res ; 15(4)2016 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-27813603

RESUMEN

Feed intake, feed efficiency, and weight gain are important economic traits of beef cattle in feedlots. In the present study, we investigated the physiological processes underlying such traits from the point of view of systems genetics. Firstly, using data from 1334 Nellore (Bos indicus) cattle and 943,577 single nucleotide polymorphisms (SNPs), a genome-wide association analysis was performed for dry matter intake, average daily weight gain, feed conversion ratio, and residual feed intake with a Bayesian Lasso procedure. Genes within 50-kb SNPs, most relevant for explaining the genomic variance, were annotated and the biological processes underlying the traits were inferred from Database for Annotation, Visualization and Integrated Discovery (DAVID) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Our results indicated several putative genomic regions associated with the target phenotypes and showed that almost all genomic variances were in the SNPs located in the intergenic and intronic regions. We further identified five main metabolic pathways related to ion transport, body composition, and feed intake control, which influenced the four phenotypes simultaneously. The systems genetics approach used in this study revealed novel pathways related to feed efficiency traits in beef cattle.


Asunto(s)
Alimentación Animal , Conducta Alimentaria , Estudio de Asociación del Genoma Completo , Carne , Biología de Sistemas/métodos , Animales , Bovinos , Genoma , Polimorfismo de Nucleótido Simple/genética , Carácter Cuantitativo Heredable
8.
Behav Genet ; 45(5): 547-59, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26026879

RESUMEN

Feingold syndrome (FS) is an autosomal dominant disorder characterized by microcephaly, short stature, digital anomalies, esophageal/duodenal atresia, facial dysmorphism, and various learning disabilities. Heterozygous deletion of the miR-17-92 cluster is responsible for a subset of FS (Feingold syndrome type 2, FS2), and the developmental abnormalities that characterize this disorder are partially recapitulated in mice that harbor a heterozygous deletion of this cluster (miR-17-92∆/+ mice). Although Feingold patients develop a wide array of learning disabilities, no scientific description of learning/cognitive disabilities, intellectual deficiency, and brain alterations have been described in humans and animal models of FS2. The aim of this study was to draw a behavioral profile, during development and in adulthood, of miR-17-92∆/+ mice, a genetic mouse model of FS2. Moreover, dopamine, norepinephrine and serotonin tissue levels in the medial prefrontal cortex (mpFC), and Hippocampus (Hip) of miR-17-92∆/+ mice were analyzed.Our data showed decreased body growth and reduced vocalization during development. Moreover, selective deficits in spatial ability, social novelty recognition and memory span were evident in adult miR-17-92∆/+ mice compared with healthy controls (WT). Finally, we found altered dopamine as well as serotonin tissue levels, in the mpFC and Hip, respectively, of miR-17-92∆/+ in comparison with WT mice, thus suggesting a possible link between cognitive deficits and altered brain neurotransmission.


Asunto(s)
Encéfalo/fisiopatología , Párpados/anomalías , Discapacidad Intelectual/fisiopatología , Deformidades Congénitas de las Extremidades/fisiopatología , Trastornos Mentales/genética , Microcefalia/fisiopatología , Fístula Traqueoesofágica/fisiopatología , Animales , Conducta Animal/fisiología , Modelos Animales de Enfermedad , Párpados/fisiopatología , Femenino , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/genética , Deformidades Congénitas de las Extremidades/complicaciones , Deformidades Congénitas de las Extremidades/genética , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Microcefalia/complicaciones , Microcefalia/genética , Fístula Traqueoesofágica/complicaciones , Fístula Traqueoesofágica/genética
9.
Scand J Med Sci Sports ; 25(6): e603-12, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25515692

RESUMEN

This study analyzed the effects of pseudoephedrine (PSE) provided at different time of day on neuromuscular performance, side effects, and violation of the current doping cut-off threshold [World Anti-Doping Agency (WADA)]. Nine resistance-trained males carried out bench press and full squat exercises against four incremental loads (25%, 50%, 75%, and 90% one repetition maximum [1RM]), in a randomized, double-blind, cross-over design. Participants ingested either 180 mg of PSE (supra-therapeutic dose) or placebo in the morning (7:00 h; AM(PLAC) and AM(PSE)) and in the afternoon (17:00 h; PM(PLAC) and PM(PSE)). PSE enhanced muscle contraction velocity against 25% and 50% 1RM loads, only when it was ingested in the mornings, and only in the full squat exercise (4.4-8.7%; P < 0.05). PSE ingestion raised urine and plasma PSE concentrations (P < 0.05) regardless of time of day; however, cathine only increased in the urine samples. PSE ingestion resulted in positive tests occurring in 11% of samples, and it rose some adverse side effects such us tachycardia and heart palpitations. Ingestion of a single dose of 180 mg of PSE results in enhanced lower body muscle contraction velocity against low and moderate loads only in the mornings. These mild performance improvements are accompanied by undesirable side effects and an 11% risk of surpassing the doping threshold.


Asunto(s)
Ritmo Circadiano/fisiología , Doping en los Deportes , Contracción Muscular/efectos de los fármacos , Descongestionantes Nasales/administración & dosificación , Seudoefedrina/administración & dosificación , Adolescente , Adulto , Estudios Cruzados , Método Doble Ciego , Humanos , Masculino , Descongestionantes Nasales/efectos adversos , Descongestionantes Nasales/metabolismo , Fenilpropanolamina/administración & dosificación , Fenilpropanolamina/efectos adversos , Fenilpropanolamina/metabolismo , Seudoefedrina/efectos adversos , Seudoefedrina/metabolismo , Entrenamiento de Fuerza , Taquicardia/inducido químicamente , Adulto Joven
10.
J Anim Breed Genet ; 132(6): 420-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26016521

RESUMEN

The aim of this study was to identify candidate genes and genomic regions associated with ultrasound-derived measurements of the rib-eye area (REA), backfat thickness (BFT) and rumpfat thickness (RFT) in Nellore cattle. Data from 640 Nellore steers and young bulls with genotypes for 290 863 single nucleotide polymorphisms (SNPs) were used for genomewide association mapping. Significant SNP associations were explored to find possible candidate genes related to physiological processes. Several of the significant markers detected were mapped onto functional candidate genes including ARFGAP3, CLSTN2 and DPYD for REA; OSBPL3 and SUDS3 for BFT; and RARRES1 and VEPH1 for RFT. The physiological pathway related to lipid metabolism (CLSTN2, OSBPL3, RARRES1 and VEPH1) was identified. The significant markers within previously reported QTLs reinforce the importance of the genomic regions, and the other loci offer candidate genes that have not been related to carcass traits in previous investigations.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Distribución de la Grasa Corporal/veterinaria , Bovinos/genética , Metabolismo de los Lípidos/genética , Sitios de Carácter Cuantitativo , Carne Roja , Animales , Marcadores Genéticos , Estudio de Asociación del Genoma Completo , Genotipo , Masculino , Fenotipo , Polimorfismo de Nucleótido Simple , Transducción de Señal , Ultrasonografía
11.
Anal Bioanal Chem ; 401(2): 517-28, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21188579

RESUMEN

Methods of blood doping such as autologous and homologous blood transfusion are one of the main challenging doping practices in competitive sport. Whereas homologous blood transfusion is detectable via minor blood antigens, the detection of autologous blood transfusion is still not feasible. A promising approach to indicate homologous or autologous blood transfusion is the quantification of increased urinary levels of di(2-ethylhexyl) phthalate (DEHP) metabolites found after blood transfusion. The commonly used plasticizer for flexible PVC products, such as blood bags, is DEHP which is known to diffuse into the stored blood. Therefore, a straight forward, rapid and reliable assay is presented for the quantification of the main metabolites mono(2-ethyl-5-oxohexyl) phthalate, mono(2-ethyl-5-hydroxyhexyl) phthalate and mono(2-ethylhexyl) phthalate that can easily be implemented into existing multi-target methods used for sports drug testing. Quantification of the DEHP metabolites was accomplished after enzymatic hydrolysis of urinary glucuronide conjugates and direct injection using isotope-dilution liquid chromatography/tandem mass spectrometry. The method was fully validated for quantitative purposes considering the parameters specificity, linearity (1-250 ng/mL), inter- (2.4%-4.3%) and intra-day precision (0.7%-6.1%), accuracy (85%-105%), limit of detection (0.2-0.3 ng/mL), limit of quantification (1 ng/mL), stability and ion suppression effects. Urinary DEHP metabolites were measured in a control group without special exposure to DEHP (n = 100), in hospitalized patients receiving blood transfusion (n = 10), and in athletes (n = 468) being subject of routine doping controls. The investigation demonstrates that significantly increased levels of secondary DEHP metabolites were found in urine samples of transfused patients, strongly indicating blood transfusion.


Asunto(s)
Transfusión Sanguínea , Dietilhexil Ftalato/metabolismo , Dietilhexil Ftalato/orina , Doping en los Deportes , Detección de Abuso de Sustancias/métodos , Adulto , Biomarcadores/sangre , Biomarcadores/metabolismo , Biomarcadores/orina , Cromatografía Liquida , Dietilhexil Ftalato/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem , Adulto Joven
12.
Anal Bioanal Chem ; 397(7): 2903-16, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20496057

RESUMEN

The objective of the present study was to investigate mesocarb metabolism in humans. Samples obtained after administration of mesocarb to healthy volunteers were studied. The samples were extracted at alkaline pH using ethyl acetate and salting-out effect to recover metabolites excreted free and conjugated with sulfate. A complementary procedure was applied to recover conjugates with glucuronic acid or with sulfate consisting of the extraction of the urines with XAD-2 columns previously conditioned with methanol and deionized water; the columns were then washed with water and finally eluted with methanol. In both cases, the dried extracts were reconstituted and analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. Chromatographic separation was carried out using a C(18) column (100 mm x 2.1 mm i.d., 1.7 microm particle size) and a mobile phase consisting of water and acetonitrile with 0.01% formic acid with gradient elution. The chromatographic system was coupled to a mass spectrometer with an electrospray ionization source working in positive mode. Metabolic experiments were performed in multiple-reaction monitoring mode by monitoring one transition for each potential mesocarb metabolite. Mesocarb and 19 metabolites were identified in human urine, including mono-, di-, and trihydroxylated metabolites excreted free as well as conjugated with sulfate or glucuronic acid. All metabolites were detected up to 48 h after administration. The structures of most metabolites were proposed based on data from reference standards available and molecular mass and product ion mass spectra of the peaks detected. The direct detection of mesocarb metabolites conjugated with sulfate and glucuronic acid without previous hydrolysis has been described for the first time. Finally, a screening method to detect the administration of mesocarb in routine antidoping control analyses was proposed and validated based on the detection of the main mesocarb metabolites in human urine (p-hydroxymesocarb and p-hydroxymesocarb sulfate). After analysis of several blank urines, the method demonstrated to be specific. Extraction recoveries of 100.3 +/- 0.8 and 105.9 +/- 10.8 (n = 4), and limits of detection of 0.5 and 0.1 ng mL(-1) were obtained for p-hydroxymesocarb sulfate and p-hydroxymesocarb, respectively. The intra- and inter-assay precisions were estimated at two concentration levels, 50 and 250 ng mL(-1), and relative standard deviations were lower than 15% in all cases (n = 4).


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Sidnonas/metabolismo , Sidnonas/orina , Espectrometría de Masas en Tándem/métodos , Humanos , Estructura Molecular , Sidnonas/química
13.
J Cell Biol ; 151(4): 905-18, 2000 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-11076973

RESUMEN

Drosophila cellularization and animal cell cytokinesis rely on the coordinated functions of the microfilament and microtubule cytoskeletal systems. To identify new proteins involved in cellularization and cytokinesis, we have conducted a biochemical screen for microfilament/microtubule-associated proteins (MMAPs). 17 MMAPs were identified; seven have been previously implicated in cellularization and/or cytokinesis, including KLP3A, Anillin, Septins, and Dynamin. We now show that a novel MMAP, Lava Lamp (Lva), is also required for cellularization. Lva is a coiled-coil protein and, unlike other proteins previously implicated in cellularization or cytokinesis, it is Golgi associated. Our functional analysis shows that cellularization is dramatically inhibited upon injecting anti-Lva antibodies (IgG and Fab) into embryos. In addition, we show that brefeldin A, a potent inhibitor of membrane trafficking, also inhibits cellularization. Biochemical analysis demonstrates that Lva physically interacts with the MMAPs Spectrin and CLIP190. We suggest that Lva and Spectrin may form a Golgi-based scaffold that mediates the interaction of Golgi bodies with microtubules and facilitates Golgi-derived membrane secretion required for the formation of furrows during cellularization. Our results are consistent with the idea that animal cell cytokinesis depends on both actomyosin-based contraction and Golgi-derived membrane secretion.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriología , Embrión no Mamífero/citología , Embrión no Mamífero/fisiología , Aparato de Golgi/fisiología , Proteínas Asociadas a Microtúbulos/metabolismo , Actinas/metabolismo , Animales , Animales Modificados Genéticamente , Membranas Intracelulares/metabolismo , Membranas Intracelulares/ultraestructura , Unión Proteica , Espectrina/metabolismo
14.
J Vet Pharmacol Ther ; 32(5): 503-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19754919

RESUMEN

The objective of the present study was to evaluate the plasma concentrations and pharmacokinetics of buprenorphine after transdermal application in dogs (n = 4). A 70 microg/h transdermal buprenorphine patch was applied to the ventral abdomen of four healthy beagles. Blood samples were collected through a preplaced jugular catheter before and at 1, 2, 4, 8, 12, 24, 36, 48 and every 6 h until 108 h after the patch application. Plasma buprenorphine concentrations were measured using a (125)I-labelled radioimmunoassay (RIA) assay. No adverse effects were observed in any of the dogs. Concentrations of buprenorphine were detected in plasma after the application of the transdermal buprenorphine patch on the four experimental animals. Buprenorphine plasma concentrations increased during the first 36 h and then remained in the 0.7-1.0 ng/mL range during the study period. A decrease in plasma buprenorphine concentration was not observed during the study. Although analgesia could not be demonstrated the present study shows the ability of buprenorphine transdermal delivery systems developed for human use to deliver measurable concetrations of buprenorphine in dogs.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Buprenorfina/administración & dosificación , Administración Cutánea , Analgésicos Opioides/sangre , Analgésicos Opioides/farmacocinética , Animales , Buprenorfina/sangre , Buprenorfina/farmacocinética , Perros/metabolismo , Masculino , Radioinmunoensayo
15.
Rev Esp Med Nucl ; 28(3): 114-20, 2009.
Artículo en Español | MEDLINE | ID: mdl-19558951

RESUMEN

INTRODUCTION: Changes in regional cerebral blood flow (rCBF) have been reported in idiopathic Parkinson's disease (PD). Nonetheless, their typical pattern still remains controversial regarding some features, such as basal ganglia involvement and the main cortical regions affected. Functional neuroimaging makes it possible to identify the brain dysfunctions of the neural circuits underlying the disease. Voxel-based analysis methods make it possible to increase the reliability of the results. OBJECTIVE: To assess the rCBF changes in patients with PD and their relation with disease duration. MATERIALS AND METHODS: Thirty PD adult patients without dementia underwent evaluation with (99m)Tc-ECD SPECT. SPM5 was used for statistical comparison with 25 normal controls of similar ages. The disease course duration in years was added as a covariate. Additionally, patients with a 6-year evolution or less and those with more than 6 years were compared separately with normal controls. RESULTS: Significant hypoperfusion was detected in bilateral premotor and posterior parietal cortex and increase of perfusion was present in the cerebellum. These changes correlated with the years of evolution of the illness. Patients with longer evolution also presented thalamic, subthalamic and basal ganglia hypoperfusion. CONCLUSIONS: We describe rCBF changes in PD in neural circuits related with control of movements. These changes are more manifest in patients with a longer duration of the disease.


Asunto(s)
Circulación Cerebrovascular , Enfermedad de Parkinson/fisiopatología , Adulto , Anciano , Cerebelo/irrigación sanguínea , Cerebelo/diagnóstico por imagen , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/diagnóstico por imagen , Factores de Confusión Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico por imagen , Estudios Prospectivos , Factores de Tiempo , Tomografía Computarizada de Emisión de Fotón Único
16.
Sci Rep ; 9(1): 16396, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31705027

RESUMEN

Although the intestinal microbiome has been increasingly implicated in autoimmune diseases, much is unknown about its roles in Multiple Sclerosis (MS). Our aim was to compare the microbiome between treatment-naïve MS subjects early in their disease course and controls, and between Caucasian (CA), Hispanic (HA), and African American (AA) MS subjects. From fecal samples, we performed 16S rRNA V4 sequencing and analysis from 45 MS subjects (15 CA, 16 HA, 14 AA) and 44 matched healthy controls, and whole metagenomic shotgun sequencing from 24 MS subjects (all newly diagnosed, treatment-naïve, and steroid-free) and 24 controls. In all three ethnic groups, there was an increased relative abundance of the same single genus, Clostridium, compared to ethnicity-matched controls. Analysis of microbiota networks showed significant changes in the network characteristics between combined MS cohorts and controls, suggesting global differences not restricted to individual taxa. Metagenomic analysis revealed significant enrichment of individual species within Clostridia as well as particular functional pathways in the MS subjects. The increased relative abundance of Clostridia in all three early MS cohorts compared to controls provides candidate taxa for further study as biomarkers or as etiologic agents in MS.


Asunto(s)
Etnicidad , Microbioma Gastrointestinal , Esclerosis Múltiple/microbiología , Adulto , Negro o Afroamericano , Estudios de Casos y Controles , Clostridium/clasificación , Clostridium/genética , Clostridium/aislamiento & purificación , Femenino , Microbioma Gastrointestinal/genética , Hispánicos o Latinos , Interacciones Microbiota-Huesped/inmunología , Humanos , Masculino , Metagenoma , Persona de Mediana Edad , Esclerosis Múltiple/inmunología , ARN Ribosómico 16S/genética , Población Blanca , Adulto Joven
17.
Herzschrittmacherther Elektrophysiol ; 30(2): 225-228, 2019 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-31049655

RESUMEN

The therapy for heart failure in patients with uncompromised systolic ventricular function (HfpEF) is still challenging because there is an obvious lack of effective therapy options. Several of these particular patients are additionally presenting atrioventricular (AV) block. In these patients HIS bundle pacing could be a hopeful therapy strategy due to the option of an AV resynchronisation as illustrated in the following case.


Asunto(s)
Bloqueo Atrioventricular , Fascículo Atrioventricular , Insuficiencia Cardíaca , Estimulación Cardíaca Artificial , Electrocardiografía , Humanos , Volumen Sistólico
18.
Theriogenology ; 125: 71-78, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30390481

RESUMEN

The main objective of this study was to verify genetic trends for milk production (MY305) and age at first calving (AFC). Were also considered levels of inbreeding practiced in the Brazilian dual-purpose Guzerá population (TPOP) comparing it with the same parameters estimated for two sub-populations derived from the reference (TPOP): female donors submitted to ovum-pick up (DPOP) and in vitro embryos produced (EPOP) between 2003 and 2013. Estimated breeding values (EBV) and inbreeding coefficients (F) were regressed by the year of birth (or year of in vitro fertilization) of each animal or embryo in order to obtain annual trends for these parameters separately for each of the three populations studied. A positive quadratic (ß2 = +0.000075) effect was detected for the F values in TPOP. Both DPOP and EPOP showed positive linear coefficients (ß1), respectively, +0.00084 (P < 0.001) and +0.00024 (P > 0.05). Annual mean F for EPOP was higher than TPOP and DPOP through the time series studied. The frequency of individuals with more than 7% F was higher in DPOP. Genetic trends for AFC were -0.187 days/year (P > 0.05); -0.557 days/year (P < 0.05) and -1.48 days/year (P < 0.05), respectively for TPOP; DPOP and EPOP. Genetic trends for MY305 were +6.75 kg/year (P < 0.001); +8.2 kg/year (P < 0.001) and +10.5 kg/year (P < 0.05), respectively for TPOP; DPOP and EPOP. For both traits analyzed, EPOP showed the highest regression coefficients, which confirms a higher selection pressure and lower generation intervals previously expected from this sub-population. Results reported in the present study suggest that mean F is increasing in the Guzerá population. Efforts for controlling inbred mating on in vitro fertilization should be considered, as the presence of a bottleneck effect seems to be getting shape on DPOP and EPOP.


Asunto(s)
Bovinos/genética , Bovinos/fisiología , Transferencia de Embrión/veterinaria , Endogamia , Donación de Oocito/veterinaria , Animales , Brasil , Técnicas de Cultivo de Embriones/veterinaria , Femenino , Fertilización In Vitro/veterinaria , Variación Genética , Lactancia/genética , Lactancia/fisiología , Embarazo , Maduración Sexual
19.
Neuroscience ; 155(2): 359-65, 2008 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-18585443

RESUMEN

In vitro, nitric oxide (NO) inhibits the firing rate of magnocellular neurosecretory cells (MNCs) of hypothalamic supraoptic and paraventricular nuclei and this effect has been attributed to GABAergic activation. However, little is known about the direct effects of NO in MNCs. We used the patch-clamp technique to verify the effect of L-arginine, a precursor for NO synthesis, and N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of NOS, on spontaneous electrical activity of MNCs after glutamatergic and GABAergic blockade in Wistar rat brain slices. 6-Cyano-7-nitroquinoxaline-2,3-dione (CNQX) (10 microM) and dl-2-amino-5-phosphonovaleric acid (dl-AP5) (30 microM) were used to block postsynaptic glutamatergic currents, and picrotoxin (30 microM) and saclofen (30 microM) to block ionotropic and metabotropic postsynaptic GABAergic currents. Under these conditions, 500 microM L-arginine decreased the firing rate from 3.7+/-0.6 Hz to 1.3+/-0.3 Hz. Conversely, 100 microM L-NAME increased the firing rate from 3.0+/-0.3 Hz to 5.8+/-0.4 Hz. All points histogram analysis showed changes in resting potential from -58.1+/-0.8 mV to -62.2+/-1.1 mV in the presence of L-arginine and from -59.8+/-0.7 mV to -56.9+/-0.8 mV by L-NAME. Despite the nitrergic modulator effect on firing rate, some MNCs had no significant changes in their resting potential. In those neurons, hyperpolarizing after-potential (HAP) amplitude increased from 12.4+/-1.2 mV to 16.8+/-0.7 mV by L-arginine, but without significant changes by L-NAME treatment. To our knowledge, this is the first demonstration that NO can inhibit MNCs independent of GABAergic inputs. Further, our results point to HAP as a potential site for nitrergic modulation.


Asunto(s)
Potenciales de Acción/fisiología , Neuronas/fisiología , Óxido Nítrico/fisiología , Núcleo Supraóptico/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Arginina/farmacología , Femenino , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , NG-Nitroarginina Metil Éster/farmacología , Neuronas/efectos de los fármacos , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Ratas , Ratas Endogámicas WF , Núcleo Supraóptico/citología , Núcleo Supraóptico/efectos de los fármacos
20.
J Mass Spectrom ; 43(7): 936-48, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18563855

RESUMEN

Doping with (glyco)protein hormones represent an extremely challenging, analytical problem as nearly all are constitutively present at low concentrations that fluctuate according to circadian or alternative periodical, or external stimuli. Thus the mere concentration in a biological sample is only resolutive when this surpasses extreme values. As the vast majority of these molecules are produced by recombinant DNA technology it is believed that the exogenous molecules could bear the signature of the host cell. In particular, these could comprise structural differences originated from co or post-translational differences. In this study we have employed both proteomics and glycomics strategies to compare recombinant and urinary human chorionic gonadotrophin in order to evaluate this hypothesis. As anticipated the recombinant hormone could be shown to contain N-glycolyl neuraminic acid, a sialic acid that cannot be produced by humans. Furthermore, differences were observed in the overall glycosylation, in particular the presence of abundant hybrid-type glycans that were much less pronounced in the recombinant species. These differences were determined to occur predominantly in the alpha-subunit for which antidoping strategies focussed on these elements could be used for both chorionic gonadotrophin and lutrophin as they share the same alpha-subunit.


Asunto(s)
Gonadotropina Coriónica/orina , Doping en los Deportes , Hormonas Glicoproteicas de Subunidad alfa/orina , Polisacáridos/orina , Detección de Abuso de Sustancias/métodos , Gonadotropina Coriónica/química , Electroforesis en Gel de Poliacrilamida , Hormonas Glicoproteicas de Subunidad alfa/química , Glicosilación , Humanos , Ácidos Neuramínicos/química , Ácidos Neuramínicos/orina , Polisacáridos/química , Procesamiento Proteico-Postraduccional , Proteómica , Proteínas Recombinantes/química , Proteínas Recombinantes/orina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA