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1.
Circulation ; 140(16): 1331-1341, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31387361

RESUMEN

BACKGROUND: Bicuspid aortic valve (BAV) disease is a congenital defect that affects 0.5% to 1.2% of the population and is associated with comorbidities including ascending aortic dilation and calcific aortic valve stenosis. To date, although a few causal genes have been identified, the genetic basis for the vast majority of BAV cases remains unknown, likely pointing to complex genetic heterogeneity underlying this phenotype. Identifying genetic pathways versus individual gene variants may provide an avenue for uncovering additional BAV causes and consequent comorbidities. METHODS: We performed genome-wide association Discovery and Replication Studies using cohorts of 2131 patients with BAV and 2728 control patients, respectively, which identified primary cilia genes as associated with the BAV phenotype. Genome-wide association study hits were prioritized based on P value and validated through in vivo loss of function and rescue experiments, 3-dimensional immunohistochemistry, histology, and morphometric analyses during aortic valve morphogenesis and in aged animals in multiple species. Consequences of these genetic perturbations on cilia-dependent pathways were analyzed by Western and immunohistochemistry analyses, and assessment of aortic valve and cardiac function were determined by echocardiography. RESULTS: Genome-wide association study hits revealed an association between BAV and genetic variation in human primary cilia. The most associated single-nucleotide polymorphisms were identified in or near genes that are important in regulating ciliogenesis through the exocyst, a shuttling complex that chaperones cilia cargo to the membrane. Genetic dismantling of the exocyst resulted in impaired ciliogenesis, disrupted ciliogenic signaling and a spectrum of cardiac defects in zebrafish, and aortic valve defects including BAV, valvular stenosis, and valvular calcification in murine models. CONCLUSIONS: These data support the exocyst as required for normal ciliogenesis during aortic valve morphogenesis and implicate disruption of ciliogenesis and its downstream pathways as contributory to BAV and associated comorbidities in humans.


Asunto(s)
Estenosis de la Válvula Aórtica/patología , Válvula Aórtica/anomalías , Cilios/fisiología , Cardiopatías Congénitas/patología , Enfermedades de las Válvulas Cardíacas/patología , Animales , Válvula Aórtica/metabolismo , Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/genética , Enfermedad de la Válvula Aórtica Bicúspide , Estudios de Casos y Controles , Cilios/patología , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Cardiopatías Congénitas/genética , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/metabolismo , Humanos , Ratones , Ratones Noqueados , Polimorfismo de Nucleótido Simple , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Pez Cebra , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
2.
Plant Dis ; 103(3): 484-494, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30632469

RESUMEN

The influence of environmental and management factors on the occurrence of foliar pathogens of watermelon was analyzed using survey-sampling data collected from commercial farms in South Carolina in spring 2015 and spring and fall 2016. A stratified two-stage cluster sampling design was used to sample symptomatic watermelon leaves from 56 fields of 27 growers in seven counties representing the main watermelon-producing areas in the state. In the sampling design, counties corresponded to strata, growers to first-stage clusters, and fields to second-stage clusters. Pathogens were identified on 100 leaves collected per field based on reproductive structures that formed on the leaves. Information about previous crops, fruit type, field size, transplanting date, first harvest date, and fungicides applied within 7 days and within 7 to 14 days prior to sampling was obtained from growers. Field alignment was determined with a compass. Survey-specific logistic regression procedures were used to analyze the effect of these factors on the probabilities of pathogen occurrence. Five fungal pathogens, Stagonosporopsis spp., Podosphaera xanthii, Cercospora citrullina, Colletotrichum orbiculare, and Myrothecium sensu lato (s.l.), and the oomycete Pseudoperonospora cubensis were included in the analyses. Among the factors we analyzed, there was a consistent increased probability of occurrence of Stagonosporopsis spp. in fields with a previous cucurbit crop, increasing probabilities of pathogen occurrence with increasing plant age, a lower probability of occurrence of some pathogens on triploid cultivars compared with diploid cultivars, and a decrease in probability of pathogen occurrence in fields aligned toward southwest or west. Application of fungicides significantly reduced the probability of observing C. citrullina, P. cubensis, and Stagonosporopsis spp. in 2015 and P. xanthii in spring 2016. This study emphasizes the importance of crop rotation and fungicide applications to manage foliar diseases of watermelon, particularly gummy stem blight, powdery mildew, and downy mildew. Crop age, cultivar type, and field alignment also were found to significantly influence the probability of pathogen occurrence. To the best of our knowledge, this is the first study examining the influence of various factors on foliar pathogens of watermelon with data collected from commercial fields.


Asunto(s)
Ascomicetos , Citrullus , Oomicetos , Ascomicetos/fisiología , Citrullus/microbiología , Citrullus/parasitología , Análisis por Conglomerados , Oomicetos/fisiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/estadística & datos numéricos , Hojas de la Planta/microbiología , Hojas de la Planta/parasitología , Factores de Riesgo , South Carolina
3.
Proc Natl Acad Sci U S A ; 112(2): 418-23, 2015 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-25548161

RESUMEN

The endoplasmic reticulum (ER) consists of a polygonal network of sheets and tubules interconnected by three-way junctions. This network undergoes continual remodeling through competing processes: the branching and fusion of tubules forms new three-way junctions and new polygons, and junction sliding and ring closure leads to polygon loss. However, little is known about the machinery required to generate and maintain junctions. We previously reported that yeast Lnp1 localizes to ER junctions, and that loss of Lnp1 leads to a collapsed, densely reticulated ER network. In mammalian cells, only approximately half the junctions contain Lnp1. Here we use live cell imaging to show that mammalian Lnp1 (mLnp1) affects ER junction mobility and hence network dynamics. Three-way junctions with mLnp1 are less mobile than junctions without mLnp1. Newly formed junctions that acquire mLnp1 remain stable within the ER network, whereas nascent junctions that fail to acquire mLnp1 undergo rapid ring closure. These findings imply that mLnp1 plays a key role in stabilizing nascent three-way ER junctions.


Asunto(s)
Retículo Endoplásmico/metabolismo , Proteínas de Homeodominio/metabolismo , Animales , Células COS , Chlorocebus aethiops , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Proteínas de Homeodominio/antagonistas & inhibidores , Proteínas de Homeodominio/genética , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteolípidos/metabolismo , ARN Interferente Pequeño/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análisis de la Célula Individual
4.
Plant Dis ; 102(11): 2285-2295, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30207511

RESUMEN

A survey of foliar pathogens of watermelon based on two-stage cluster sampling was conducted on commercial farms in South Carolina in spring 2015, spring and fall 2016, and fall 2017. In total, 60 fields from 27 different growers in seven counties representing the main watermelon-producing areas in the state were sampled, using a stratified two-stage cluster sampling approach. In the sampling design, counties corresponded to strata, growers to first-stage clusters, and fields to second-stage clusters. In each field, 100 symptomatic leaves were collected at five equidistant sampling points along four transects encompassing a square shape of 2,500 m2. After collection, pathogens were identified based on reproductive structures formed on leaves during >12 h incubation. Estimates were obtained for the statewide probability of pathogen occurrence and associations between pathogen pairs. Six fungal pathogens, Stagonosporopsis spp., Podosphaera xanthii, Cercospora citrullina, Colletotrichum orbiculare, Myrothecium sensu lato (s.l.), and Corynespora cassiicola; the oomycete Pseudoperonospora cubensis; and three viral pathogens were identified on the examined leaves. With the exception of fall 2017, Stagonosporopsis spp. was the most prevalent pathogen in every season, followed by P. xanthii. The highest occurrence of P. cubensis was in spring 2015; it did not occur in 2016. The highest occurrence of C. orbiculare was in spring 2016; it did not occur in spring 2015. Myrothecium s.l. was the most common pathogen in fall 2017 and the second most common pathogen occurring by itself in fall 2016. The third most common pathogen in fall 2017, Corynespora cassiicola, was not observed in any other season. Eight of the 80 isolates of Stagonosporopsis spp. collected were identified as S. caricae, the rest as S. citrulli. All isolates of S. caricae were found in spring 2015 and originated from two fields in different counties. A total of three positive and five negative associations were found between pathogen pairs co-occurring on the same leaf. A positive association between Stagonosporopsis spp. and C. citrullina was the only significant association between pathogens found in two seasons, spring 2015 and spring 2016. Based on estimates of probability of pathogen occurrence across seasons, Stagonosporopsis spp. and P. xanthii are the most common pathogens on watermelons in South Carolina. This is the first report of C. cassiicola, S. caricae, and Myrothecium s.l. on watermelon in South Carolina.


Asunto(s)
Ascomicetos/aislamiento & purificación , Citrullus/microbiología , Oomicetos/aislamiento & purificación , Enfermedades de las Plantas/estadística & datos numéricos , Citrullus/parasitología , Análisis por Conglomerados , Ambiente , Granjas , Modelos Estadísticos , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/parasitología , Hojas de la Planta/microbiología , Hojas de la Planta/parasitología , Estaciones del Año , South Carolina
5.
Environ Monit Assess ; 190(5): 272, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29637320

RESUMEN

Dissolved oxygen is a critical component of river water quality. This study investigated average weekly dissolved oxygen (AWDO) and average weekly water temperature (AWT) in the Savannah River during 2015 and 2016 using data from the Intelligent River® sensor network. Weekly data and seasonal summary statistics revealed distinct seasonal patterns that impact both AWDO and AWT regardless of location along the river. Within seasons, spatial patterns of AWDO and AWT along the river are also evident. Linear mixed effects models indicate that AWT and low and high river flow conditions had a significant impact on AWDO, but added little predictive information to the models. Low and high river flow conditions had a significant impact on AWT, but also added little predictive information to the models. Spatial linear mixed effects models yielded parameter estimates that were effectively the same as non-spatial linear mixed effects models. However, components of variance from spatial linear mixed effects models indicate that 23-32% of the total variance in AWDO and that 12-18% of total variance in AWT can be apportioned to the effect of spatial covariance. These results indicate that location, week, and flow-directional spatial relationships are critically important considerations for investigating relationships between space- and time-varying water quality metrics.


Asunto(s)
Monitoreo del Ambiente/métodos , Oxígeno/análisis , Ríos/química , Temperatura , Agua Dulce , Estaciones del Año , Calidad del Agua
6.
Proc Biol Sci ; 284(1846)2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28053058

RESUMEN

Fluid-feeding insects, such as butterflies, moths and flies (20% of all animal species), are faced with the common selection pressure of having to remove and feed on trace amounts of fluids from porous surfaces. Insects able to acquire fluids that are confined to pores during drought conditions would have an adaptive advantage and increased fitness over other individuals. Here, we performed feeding trials using solutions with magnetic nanoparticles to show that butterflies and flies have mouthparts adapted to pull liquids from porous surfaces using capillary action as the governing principle. In addition, the ability to feed on the liquids collected from pores depends on a relationship between the diameter of the mouthpart conduits and substrate pore size diameter; insects with mouthpart conduit diameters larger than the pores cannot successfully feed, thus there is a limiting substrate pore size from which each species can acquire liquids for fluid uptake. Given that natural selection independently favoured mouthpart architectures that support these methods of fluid uptake (Diptera and Lepidoptera share a common ancestor 280 Ma that had chewing mouthparts), we suggest that the convergence of this mechanism advocates this as an optimal strategy for pulling trace amounts of fluids from porous surfaces.


Asunto(s)
Estructuras Animales/anatomía & histología , Mariposas Diurnas/anatomía & histología , Conducta Alimentaria , Mariposas Nocturnas/anatomía & histología , Animales
7.
Circ Res ; 117(11): e80-9, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26443597

RESUMEN

RATIONALE: Matrix metalloproteinases (MMPs)-mediated extracellular matrix destruction is the major cause of development and progression of abdominal aortic aneurysms. Systemic treatments of MMP inhibitors have shown effectiveness in animal models, but it did not translate to clinical success either because of low doses used or systemic side effects of MMP inhibitors. We propose a targeted nanoparticle (NP)-based delivery of MMP inhibitor at low doses to the abdominal aortic aneurysms site. Such therapy will be an attractive option for preventing expansion of aneurysms in patients without systemic side effects. OBJECTIVE: Our previous study showed that poly(d,l-lactide) NPs conjugated with an antielastin antibody could be targeted to the site of an aneurysm in a rat model of abdominal aortic aneurysms. In the study reported here, we tested whether such targeted NPs could deliver the MMP inhibitor batimastat (BB-94) to the site of an aneurysm and prevent aneurysmal growth. METHODS AND RESULTS: Poly(d,l-lactide) NPs were loaded with BB-94 and conjugated with an elastin antibody. Intravenous injections of elastin antibody-conjugated BB-94-loaded NPs targeted the site of aneurysms and delivered BB-94 in a calcium chloride injury-induced abdominal aortic aneurysms in rats. Such targeted delivery inhibited MMP activity, elastin degradation, calcification, and aneurysmal development in the aorta (269% expansion in control versus 40% elastin antibody-conjugated BB-94-loaded NPs) at a low dose of BB-94. The systemic administration of BB-94 alone at the same dose was ineffective in producing MMP inhibition. CONCLUSIONS: Targeted delivery of MMP inhibitors using NPs may be an attractive strategy to inhibit aneurysmal progression.


Asunto(s)
Aorta Abdominal/efectos de los fármacos , Aneurisma de la Aorta Abdominal/tratamiento farmacológico , Portadores de Fármacos , Inmunoconjugados/administración & dosificación , Inhibidores de la Metaloproteinasa de la Matriz/administración & dosificación , Metaloproteinasas de la Matriz/metabolismo , Nanopartículas , Fenilalanina/análogos & derivados , Poliésteres/química , Tiofenos/administración & dosificación , Animales , Aorta Abdominal/enzimología , Aorta Abdominal/inmunología , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/inducido químicamente , Aneurisma de la Aorta Abdominal/enzimología , Aneurisma de la Aorta Abdominal/inmunología , Aneurisma de la Aorta Abdominal/patología , Cloruro de Calcio , Química Farmacéutica , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Elastina/inmunología , Elastina/metabolismo , Inmunoconjugados/química , Inmunoconjugados/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Masculino , Inhibidores de la Metaloproteinasa de la Matriz/química , Inhibidores de la Metaloproteinasa de la Matriz/metabolismo , Ratones , Fenilalanina/administración & dosificación , Fenilalanina/química , Fenilalanina/metabolismo , Proteolisis , Células RAW 264.7 , Ratas Sprague-Dawley , Tiofenos/química , Tiofenos/metabolismo , Factores de Tiempo , Calcificación Vascular/enzimología , Calcificación Vascular/patología , Calcificación Vascular/prevención & control
8.
J Chem Ecol ; 43(2): 129-142, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28050732

RESUMEN

Environmental stress hinders growth of plants and commonly results in the accumulation of carbon-based defense compounds. However, the dynamics of nitrogen (N)-containing defense compounds are less predictable under environmental stress. The impact of nutrient deficiency on plant defenses that require the metabolic conversion of a less toxic compound to a more potent toxin is even more poorly understood. We evaluated the effects of nitrogen (N) and potassium (K) deficiency and simulated herbivory on the concentration of metabolites including glucosinolates (GSLs), on the conversion of GSLs to more toxic isothiocyanates (ITCs), and on the activity of myrosinase (MYR) in leaves of Brassica juncea and Brassica nigra. Both species contained GSLs, predominantly sinigrin, but also derivatives of glucobrassicin. Compared to the control, N deficiency increased the sinigrin concentration in both species. Methyl jasmonate (MeJA) application increased sinigrin production in B. junceae, whereas in B. nigra MeJA increased sinigrin only under K-deficiency. Compared to the aliphatic-glucosinolates, MeJA application produced a greater compositional change in the profiles of indolic-glucosinolates. In both species the increase in sinigrin content of the tissue was associated with a decrease in its overall nutritive value as assessed by the content of sugars and amino acids. In B. juncea, application of MeJA decreased the conversion of sinigrin to allyl isothiocyanate (AITC) under both N and K deficiency. The potential activity of MYR decreased in both species under N deficiency. The reduced conversion of sinigrin to AITC and the lower activity of MYR suggest that the GSL-ITC defense system might have a limited efficiency in deterring generalist herbivores under environmental stress.


Asunto(s)
Glucosinolatos/metabolismo , Herbivoria , Modelos Biológicos , Planta de la Mostaza/metabolismo , Nitrógeno/deficiencia , Potasio/metabolismo , Acetatos/farmacología , Ciclopentanos/farmacología , Glicósido Hidrolasas/metabolismo , Planta de la Mostaza/crecimiento & desarrollo , Planta de la Mostaza/parasitología , Oxilipinas/farmacología , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Estrés Fisiológico
9.
Vet Surg ; 46(8): 1110-1115, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28817191

RESUMEN

OBJECTIVE: To determine whether 2.0 mm cancellous screws are superior to 2.0 mm cortical screws when inserted into cancellous and bicortical bone. STUDY DESIGN: Biomechanical study. METHODS: The 2.0 mm cancellous screws and 2.0 mm cortical screws were inserted according to the recommended guidelines in synthetic cancellous and bicortical blocks. Fifteen screw-block constructs per group were tested to failure in axial pullout. Axial pullout strength and yield strength were calculated. Data were analyzed using a one-way ANOVA. RESULTS: The 2.0 mm cortical screws achieved lower axial pullout strength than 2.0 mm cancellous screws in cancellous blocks. The 2.0 mm cortical screws achieved greater pullout strength than 2.0 mm cancellous screws in bicortical blocks. CONCLUSION: The 2.0 mm cancellous screws may offer a biomechanical advantage in bone with thin cortices (<1 mm thick), whereas 2.0 mm cortical screws may be preferred in cortical bone with cortices measuring at least 1 mm in thickness.


Asunto(s)
Tornillos Óseos/veterinaria , Hueso Esponjoso/cirugía , Hueso Cortical/cirugía , Fenómenos Biomecánicos , Tornillos Óseos/clasificación
10.
Phytopathology ; 105(5): 674-83, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25412010

RESUMEN

Reniform nematode (RN) is an important pest in cotton production. Knowledge of the distribution patterns of RN is essential for selecting sampling strategies and for site-specific management. A 3-year study was conducted in two fields in South Carolina with the purpose of characterizing the distribution of RN using a fine-scale sampling scheme in plots representing different soil textures (field 1), and using a large-scale arbitrary sampling scheme (field 2). Horizontal distribution data showed an aggregated pattern of RN densities at planting and after harvest in both fields each year, with patches ranging from 8 to 12 m. However, a significant neighborhood structure was only detected when suitable hosts (cotton and soybean) were planted. Correlations between RN densities and percent sand and silt were detected, showing nematode densities peaked when sand content was around 60% and declined when sand content increased above 60 to 65%. When fewer samples were taken in the field with more uniform sand content, percentage of sand was a less reliable predictor of RN densities. Vertical sampling showed the highest numbers of RN were found at 15 to 30 cm deep after cotton, but were deeper after a nonhost crop. Understanding distribution patterns of RN within a field may improve the effectiveness of management practices.


Asunto(s)
Gossypium/parasitología , Nematodos/fisiología , Enfermedades de las Plantas/parasitología , Agricultura/métodos , Animales , Demografía , Suelo/química
11.
J Econ Entomol ; 108(4): 1961-71, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26470341

RESUMEN

Linepithema humile (Mayr), the Argentine ant, is an invasive pest that has spread throughout the United States and is a problem in natural and managed habitats in South Carolina. Foraging patterns and the effectiveness of liquid baits for control of this pest have been studied in urban areas. However, similar studies have not been conducted in natural areas such as parks, picnic grounds, or campsites. L. humile populations can be large and widespread, making them a major nuisance pest for visitors to these natural areas. The primary objective of this study was to determine an effective distance between bait stations for control of L. humile in a natural area. A double antibody-sandwich enzyme-linked immunosorbent assay (DAS-ELISA) procedure was used to detect individual ants that consumed rabbit immunoglobin (IgG) protein for marking and tracking. In both lab and field conditions, there was a significant difference in the detection of IgG in ants fed protein marker mixed with sugar water compared with ants only fed sugar water. Additional field studies revealed that an individual ant could retain detectable levels of protein marker for 3 d and that an ant feeding on IgG containing bait could be detected over 15 m from the original bait source. Overall, we found that using liquid ant baits, with a placement of 20 m between stations, was effective in reducing L. humile numbers between April to October, 2012 in a natural park area of Lake Greenwood State Park, SC.


Asunto(s)
Hormigas/fisiología , Control de Insectos/métodos , Animales , Conducta Apetitiva , Ensayo de Inmunoadsorción Enzimática , Parques Recreativos , South Carolina
12.
Poult Sci ; 94(9): 2108-13, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26217033

RESUMEN

Mycoplasma gallisepticum (MG) is a major and economically significant pathogen of avian species. When administered before lay, F-strain MG (FMG) can reduce egg production during lay, but the ts-11 strain of MG (ts11MG) does not exert this effect. Two trials were conducted to determine the effects of pre-lay vaccinations of ts11MG, MG-Bacterin (MGBac), or their combination, in conjunction with an FMG challenge overlay after peak production on the blood characteristics of commercial layers. In each trial, 160 mycoplasma-free Hy-Line W-36 layers were housed in negative-pressure biological isolation units (4 units per treatment, 10 birds per unit) from 9 through 52 wk of age (woa). The following vaccination treatments were administered at 10 woa: 1) Control (no vaccinations); 2) MGBac; 3) ts11MG; and 4) ts11MG and MGBac combination (ts11MG+MGBac). At 45 woa, half of the birds were challenged with a laboratory stock of high-passage FMG. Parameters measured in both trials were whole-blood hematocrit and serum concentrations of cholesterol (SCHOL), triglycerides, calcium, and total protein (STP). An age×treatment interaction (P=0.04) was observed for STP between 23 and 43 woa. The STP concentration in the ts11MG and ts11MG+MGBac groups was higher at 33 woa, but was lower at 43 woa, in comparison to the Control group. Also, at 38 woa, the STP of the ts11MG+MGBac group was higher than that of the MGBac group. Although use of the ts11MG vaccine alone or in combination with MGBac may influence circulating STP concentrations when administered before lay, it remains effective in protecting layers against the adverse effect of a post-peak challenge of FMG on egg production, as was observed in a previous companion study.


Asunto(s)
Vacunas Bacterianas/farmacología , Sangre/efectos de los fármacos , Pollos/sangre , Animales , Vacunas Bacterianas/administración & dosificación , Análisis Químico de la Sangre/veterinaria , Femenino , Hematócrito/veterinaria , Vacunas Combinadas/administración & dosificación , Vacunas Combinadas/farmacología
13.
Vet Surg ; 42(7): 860-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24015804

RESUMEN

OBJECTIVE: To radiographically define the anatomic origin and insertion of the cranial cruciate ligament translated to the lateral radiographic projection of the stifle (CrCL-Lo and CrCL-Li, respectively), to correlate these landmarks for identification of the CrCL-Lo intraoperatively, and to compare the isometry of the CrCL-Lo to the lateral fabella. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Pelvic limbs (n = 12) from dogs weighing 13-26 kg. METHODS: A radiographic quadrant method was used to localize the CrCL-Lo. Mediolateral radiographic projections of each stifle were taken through a range of motion. Maximum percent change in length between each tibial marker and femoral marker during range of motion determined isometry. RESULTS: The CrCL-Lo is located at the caudal 33% and distal 50% of the lateral femoral condyle using Blumensaat's line or a line from the origin of the long digital extensor (LDE) to the lateral fabella, with no significant difference (P = .766) between the 2 reference lines. The CrCL-Li is located at the proximal 20% of the tibial plateau. No significant difference (P < .05) in isometry was found between the CrCL-Lo and lateral fabella. CONCLUSION: The CrCL-Lo is located at the caudal 1/3 and distal ½ of the lateral femoral condyle. The CrCL-Lo and lateral fabella are not significantly different in isometry when used as a proximal anchor point in extracapsular stifle stabilization.


Asunto(s)
Ligamento Cruzado Anterior/anatomía & histología , Ligamento Cruzado Anterior/diagnóstico por imagen , Perros/anatomía & histología , Rodilla de Cuadrúpedos/anatomía & histología , Rodilla de Cuadrúpedos/diagnóstico por imagen , Animales , Fenómenos Biomecánicos , Cadáver , Contracción Isométrica , Radiografía
14.
Vet Surg ; 42(2): 217-22, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23373750

RESUMEN

OBJECTIVE: To determine acute load to failure (ALF) and suture abrasion (SA) at 0° and 90° for a novel screw-type mini-anchor design. STUDY DESIGN: Biomechanical in vitro study. SAMPLE POPULATION: Synthetic bone. METHODS: Twenty mini-anchors were inserted into synthetic bone blocks assigned to 1 of 2 groups (0° ALF, 90° ALF). Pullout was performed at 5 mm/min. ALF, yield strength and stiffness were calculated. SA constructs were created with 4 groups of 5 anchors each with either 30 lb nylon leader line (NLL), 40 lb NLL, #2 Fiberwire or #5 Fiberwire. SA was performed at 0° and 90° with a sinusoidal wave form at 0.5 Hz and 10 N load for 1000 cycles or until failure. Data were summarized as mean ± SD. ALF data were analyzed using t-tests. SA data were analyzed using log rank, Tukey-adjusted pairwise comparisons and sign tests. Significance was set at P = .05. RESULTS: Mean ± SD ALF at 0° and 90° was 431.8 ± 70.8 N and 683 ± 48.7 N, respectively. 90° ALF was significantly higher. Yield strength and stiffness were not significantly different at 0° and 90°. #5 and #2 Fiberwire survived significantly more cycles than 40 lb and 30 lb NLL at 90°. At 0°, 30 lb NLL survived significantly less cycles than either Fiberwire size. Suture orientation did not have a significant effect on SA for Fiberwire constructs. CONCLUSION: The novel mini-anchor has ALF comparable to other mini-anchors. Fiberwire survived more cycles in the novel anchor eyelet than NLL and FW suture orientation in the eyelet did not affect SA.


Asunto(s)
Tornillos Óseos/veterinaria , Animales , Fenómenos Biomecánicos , Tornillos Óseos/normas , Huesos/cirugía , Falla de Equipo , Técnicas In Vitro , Suturas/normas , Suturas/veterinaria , Soporte de Peso
15.
Animals (Basel) ; 13(3)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36766288

RESUMEN

Effects of the in ovo injection of various levels of L-ascorbic acid (L-AA) on the performance and corneal erosion incidence in Ross 708 broilers exposed to 50 parts per million (ppm) of atmospheric ammonia (NH3) after hatch were determined. A total of 1440 Ross 708 broiler embryos were randomly assigned to 4 treatments: non-injected (control), 0.85% sterile saline-injected (control), or saline containing 12 or 25 mg of L-AA. At hatch, 12 male chicks were randomly assigned to each of 48 battery cages with 12 replicate cages randomly assigned to each treatment group. All birds were exposed to 50 ppm of NH3 for 35 d and the concentration of NH3 in the battery cage house was recorded every 20 s. Mortality was determined daily, and mean body weight (BW), BW gain (BWG), average daily BW gain (ADG), and feed intake, as well as feed conversion ratio (FCR), were determined weekly. From 0 to 35 d of post-hatch age (doa), six birds from each cage were selected and sampled for eye erosion scoring. Incidences of corneal erosion were significantly higher at 21 and 28 doa in comparison to those at 14 and 35 doa, and at 21 doa, birds in the saline-injected group exhibited a higher incidence of corneal erosion compared to all other treatment groups. The in ovo injection of 12 mg of L-AA increased BWG (p = 0.043) and ADG (p = 0.041), and decreased FCR (p = 0.043) from 0 to 28 doa in comparison to saline-injected controls. In conclusion the in ovo administration of 12 mg of L-AA may have the potential to improve the live performance of broilers chronically exposed to high aerial NH3 concentrations, but further study is needed to determine the physiological and immunological factors that may contribute to this improvement.

16.
New Phytol ; 196(4): 1122-1132, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23025512

RESUMEN

By inhibiting soil enzymes, tannins play an important role in soil carbon (C) and nitrogen (N) mineralization. The role of tannin chemistry in this inhibitory process, in conjunction with enzyme classes and isoforms, is less well understood. Here, we compared the inhibition efficiencies of mixed tannins (MTs, mostly limited to angiosperms) and condensed tannins (CTs, produced mostly by gymnosperms) against the potential activity of ß-glucosidase (BG), N-acetyl-glucosaminidase (NAG), and peroxidase in two soils that differed in their vegetation histories. Compared with CTs, MTs exhibited 50% more inhibition of almond (Prunus dulcis) BG activity and greater inhibition of the potential NAG activity in the gymnosperm-acclimatized soils. CTs exhibited lower BG inhibition in the angiosperm-acclimated soils, whereas both types of tannins exhibited higher peroxidase inhibition in the angiosperm soils than in gymnosperm soils. At all of the tested tannin concentrations, irrespective of the tannin type and site history, the potential peroxidase activity was inhibited two-fold more than the hydrolase activity and was positively associated with the redox-buffering efficiency of tannins. Our finding that the inhibitory activities and mechanisms of MTs and CTs are dependent on the vegetative history and enzyme class is novel and furthers our understanding of the role of tannins and soil isoenzymes in decomposition.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Hojas de la Planta/química , Suelo , Taninos/química , Taninos/farmacología , Acetilglucosaminidasa/antagonistas & inhibidores , Acetilglucosaminidasa/metabolismo , Antioxidantes/farmacología , Cycadopsida/química , Ecosistema , Magnoliopsida/química , Peroxidasas/antagonistas & inhibidores , Peroxidasas/metabolismo , Pinus/química , Proantocianidinas/química , Proantocianidinas/farmacología , Prunus/enzimología , Quercus/química , Relación Estructura-Actividad , beta-Glucosidasa/antagonistas & inhibidores , beta-Glucosidasa/metabolismo
17.
Plant Dis ; 96(10): 1438-1444, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30727315

RESUMEN

The use of resistant and tolerant cultivars is an important component of an integrated management plan for foliar nematodes on hosta. In order to identify tolerance and resistance in commercial hosta cultivars, reliable and efficient screening methods are required. To optimize the screening protocol, a series of greenhouse experiments was conducted using six hosta cultivars and two types of nematode inoculum. The pathogenicity and reproduction of Aphelenchoides fragariae maintained on fungal cultures versus maintenance on hosta were evaluated with two inoculation methods (with injury and without injury). Both sources of inoculum were pathogenic on all six cultivars tested but the plant inoculum caused two to eight times larger lesions than the fungus inoculum. Both inocula caused larger lesions and resulted in higher reproduction rates on injured leaves than on noninjured leaves. Water soaking was more efficient than traditional Baermann funnel extraction methods. Correlations between foliage symptom severity and nematode reproduction were low or nonexistence. A numerical scale for faster assessment of disease severity was developed, and recommendations for a reliable protocol for assessment of resistance and tolerance are discussed.

18.
Biofilm ; 4: 100090, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36389263

RESUMEN

Filamentous fungi are ubiquitous and frequent components of biofilms. A means to visualize them and quantify their viability is essential for understanding their development and disruption. However, quantifying filamentous fungal biofilms poses challenges because, unlike yeasts and bacteria, they are not composed of discrete cells of similar size. This research focused on filamentous fungal biofilms that are representative of those in the built environment. The objective of this study was to develop a rapid method to examine biofilm structure and quantify live (metabolically active/ membrane undamaged) and dead (inactive/ membrane damaged) cells in Aspergillus niger biofilms utilizing a fluorescent probe staining method and confocal laser scanning microscopy (CLSM). For this, we compared two commercially available probe staining kits that have been developed for bacterial and yeast systems. One method utilized the classic cell stain FUN 1 that exhibits orange-red fluorescent intravacuolar structures in metabolically active cells, while dead cells are fluoresced green. The second method utilized a combination of SYTO9 and propidium iodide (PI), and stains cells based on their membrane morphology. SYTO9 is a green fluorescent stain with the capacity to penetrate the living cell walls, and PI is a red fluorescent stain that can only penetrate dead or dying cells with damaged cell membranes. Following staining, the biofilms were imaged using CLSM and biofilm volumes and thickness were quantified using COMSTAT, a computer program that measures biofilm accumulation from digital image stacks. The results were compared to independent measurements of live-dead cell density, as well as a classic cell viability assay-XTT. The data showed that the combination of SYTO9 and PI is optimal for staining filamentous fungal biofilms.

19.
Cardiovasc Eng Technol ; 13(2): 343-361, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34668143

RESUMEN

PURPOSE: Blood pressure, cardiac output, and ventricular volumes correlate to various subject features such as age, body size, and exercise intensity. The purpose of this study is to quantify this correlation through regression modeling. METHODS: We conducted a systematic review to compile reference data of healthy subjects for several cardiovascular parameters and subject features. Regression algorithms used these aggregate data to formulate predictive models for the outputs-systolic and diastolic blood pressure, ventricular volumes, cardiac output, and heart rate-against the features-age, height, weight, and exercise intensity. A simulation-based procedure generated data of virtual subjects to test whether these regression models built using aggregate data can perform well for subject-level predictions and to provide an estimate for the expected error. The blood pressure and heart rate models were also validated using real-world subject-level data. RESULTS: The direction of trends between model outputs and the input subject features in our study agree with those in current literature. CONCLUSION: Although other studies observe exponential predictor-output relations, the linear regression algorithms performed the best for the data in this study. The use of subject-level data and more predictors may provide regression models with higher fidelity. SIGNIFICANCE: Models developed in this study can be useful to clinicians for personalized patient assessment and to researchers for tuning computational models.


Asunto(s)
Sistema Cardiovascular , Ejercicio Físico , Adulto , Presión Sanguínea/fisiología , Tamaño Corporal , Gasto Cardíaco/fisiología , Ejercicio Físico/fisiología , Humanos , Volumen Sistólico
20.
Animals (Basel) ; 12(9)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35565547

RESUMEN

The transmission of the ts-11 strain of Mycoplasma gallisepticum (MG) vaccine (ts-11MGV) between incubated eggs and between hatchlings that was administrated via in ovo injection, and its subsequent effects on their posthatch performance were evaluated. Marek's disease diluent alone (sham-injected) or containing either 3.63 × 101, 102, 103, or 104 cfu of ts-11MGV was manually in ovo-injected into the amnion on 18 days of incubation. Egg residue analysis, percentage incubational egg weight loss, hatchability of viable injected eggs, and hatchling body weight (BW) were assessed. Selected hatchlings from each treatment replicate group were swabbed in the choanal cleft for MG DNA detection. Female chick live performance was also assessed through 21 days of posthatch age. Unexposed control sentinel chicks were allocated to each treatment replicate group to assess horizontal transmission. Birds were later swabbed and bled respectively, for detection of MG DNA and IgM production at 21 days posthatch. In all birds, no MG DNA was detected and SPA tests for IgM were negative. Among all variables, only 0 to 21 day BW gain was significantly affected by treatment and was lower in the 3.63 × 104 ts-11 MGV treatment in comparison to all the other treatments. Because ts-11MGV does not exhibit vertical or horizontal transmission capabilities under commercial conditions, it may not be a good candidate for in ovo injection.

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