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1.
Nature ; 620(7972): 47-60, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37532811

RESUMEN

Artificial intelligence (AI) is being increasingly integrated into scientific discovery to augment and accelerate research, helping scientists to generate hypotheses, design experiments, collect and interpret large datasets, and gain insights that might not have been possible using traditional scientific methods alone. Here we examine breakthroughs over the past decade that include self-supervised learning, which allows models to be trained on vast amounts of unlabelled data, and geometric deep learning, which leverages knowledge about the structure of scientific data to enhance model accuracy and efficiency. Generative AI methods can create designs, such as small-molecule drugs and proteins, by analysing diverse data modalities, including images and sequences. We discuss how these methods can help scientists throughout the scientific process and the central issues that remain despite such advances. Both developers and users of AI toolsneed a better understanding of when such approaches need improvement, and challenges posed by poor data quality and stewardship remain. These issues cut across scientific disciplines and require developing foundational algorithmic approaches that can contribute to scientific understanding or acquire it autonomously, making them critical areas of focus for AI innovation.


Asunto(s)
Inteligencia Artificial , Proyectos de Investigación , Inteligencia Artificial/normas , Inteligencia Artificial/tendencias , Conjuntos de Datos como Asunto , Aprendizaje Profundo , Proyectos de Investigación/normas , Proyectos de Investigación/tendencias , Aprendizaje Automático no Supervisado
3.
J Dairy Sci ; 107(6): 3916-3926, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38331177

RESUMEN

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of bovine paratuberculosis, also known as Johne's disease. This infection is responsible for negative effects, ranging from reduction of milk production to reproductive compromise and increased susceptibility to other diseases such as mastitis. Contradictory information on the association between this infection and reproductive performance has been reported in dairy cows. The aim of this work was to investigate associations between individual cow MAP seropositivity and lifetime reproduction and production performance. The MAP serum ELISA (IDEXX MAP Ac) results from all the 13,071 adult cows present on 191 farms and corresponding birth- and calving-date records obtained from the National Association for Genetic Improvement of Dairy Cattle were used. Cows and farms were classified as positive or negative, based on ELISA results. Outcomes assessed were age at first calving (AFC), intercalving intervals (ICI) from first to fourth interval, and average milk production per day of productive cycle (Milk-305/ICI, a ratio between 305-d corrected milk production and the number of days of the respective calving interval). Multilevel mixed models were used to investigate the association of cow MAP status with AFC, ICI, and Milk-305/ICI. Three levels were considered in the models: "measurement occasion," the first level, was nested within cows and cows were nested within farms. The "measurement occasion" is the time point to which all the observed measures (between 2 successive parturitions, such as milk production and somatic cell count) were referred. Our results indicate that MAP-positive cows have a significantly lower 14-d mean AFC than MAP-negative cows. The overall average ICI in our study was 432.5 d (standard deviation: 94.6). The average ICI, from first to fourth, was not significantly affected by MAP seropositivity. No significant effect of MAP positivity was found on the overall ICI. In relation to Milk-305/ICI, MAP-positive cows did not produce significantly less milk than negative cows across their productive lifetime. We observed higher but nonsignificant Milk-305/ICI (kg/d) in MAP-positive cows. In our study, the proportion of MAP-positive cows within lactations remained similar across all lactations, suggesting that seropositivity did not increased drop-off rate.


Asunto(s)
Enfermedades de los Bovinos , Lactancia , Leche , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis , Animales , Bovinos , Femenino , Enfermedades de los Bovinos/microbiología , Reproducción , Embarazo
4.
J Org Chem ; 88(19): 14033-14047, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37712931

RESUMEN

The direct and selective conversion of a C-H bond into a C-Se bond remains a significant challenge, which is even more intricate with substrates having an innate regioselectivity under several reaction conditions, such as chalcogenophenes. We overrode their selectivity toward selanylation using palladium, copper, and the 2-(methylthio)amide directing group. This chelation-assisted direct selanylation was also suitable for mono and double ortho functionalization of arenes. The mechanistic studies indicate high-valent Pd(IV) species in the catalytic cycle, a reversible C-H activation step, and Cu(II) as a sequestering agent for organoselenide byproducts.

6.
Chemistry ; 28(7): e202103768, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34882839

RESUMEN

The search for a unique molecular system able to efficiently emit in the total visible range of the electromagnetic spectra, i. e., white light emission (WLE), is a topic of intense research. We here show that aggregates formed by diphenylbenzofulvene (DPBF) derivatives are from two to four orders of magnitude more emissive than their monomers. From a simple strategy, involving structural modification of a DPBF propelled shape core, a close match with the pure white light emission coordinates is obtained with a combination of two derivatives in films, with featured solid-state emission, without involvement of D-A groups or energy transfer processes.

7.
J Chem Ecol ; 48(5-6): 502-517, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35841479

RESUMEN

In a previous study, we reported the identification and synthesis of a male-specific sex pheromone component of the stink bug, Pellaea stictica, as the alcohol 2,4,8,13-tetramethyltetradecan-1-ol (1). To establish the correlation between the stereochemistry of the pheromone and its bioactivity, it first was necessary to determine its absolute configuration. For this purpose, a series of syntheses were designed to: (a) furnish a mixture of all possible stereoisomers; (b) a narrowed down group of diastereomers, and (c) one specific enantiomer. A crucial step in the syntheses involved a coupling reaction between two key intermediates: a phosphonium salt and an aldehyde, through a Wittig olefination. Nuclear magnetic resonance data of a mixture of the synthetic pheromone diastereomers and further comparison of GC retention times with that of the natural product by gas chromatography suggested that the methyl branches at C2 and C4 were in a syn relationship, reducing the possibilities to only four of the eight possible stereoisomers. Employing GC analysis, chiral derivatization reagents and synthetic (8R)-2,4-syn-1 it was possible to confirm the configuration of the methyl branch at C8 as R, reducing the number of possible stereoisomers to two. After enantioselective synthesis of (2R,4R,8R)-1, the absolute configurations of all methyl branches of the natural compound were confirmed as R, fully identifying the male-produced sex pheromone of P. stictica as (2R,4R,8R)-2,4,8,13-tetramethyltetradecan-1-ol.


Asunto(s)
Heterópteros , Atractivos Sexuales , Animales , Alcoholes Grasos , Heterópteros/química , Masculino , Feromonas , Atractivos Sexuales/química , Estereoisomerismo
8.
Molecules ; 26(21)2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34771061

RESUMEN

Metalloporphyrins are involved in many and diverse applications that require the preparation of these compounds in an efficient manner, which nowadays, also involves taking into consideration sustainability issues. In this context, we use ball milling mechanochemistry and sonochemistry for the rational development of synthetic strategies for the sustainable preparation of metalloporphyrins. Zinc, copper, cobalt and palladium complexes of hydrophobic porphyrins were obtained in high yields and under mechanical action with a moderate excess of the metal salt, without any solvent or additive. Sonochemistry prove to be a good alternative for the preparation of metal complexes of water-soluble porphyrins in good yields and short reaction times. Both strategies have good sustainability scores, close to the ideal values, which is useful in comparing and helping to choose the more adequate method.

9.
Helicobacter ; 25 Suppl 1: e12739, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32918356

RESUMEN

Gastric cancer is still one of the most prevalent and deadliest cancers in the world. Although our knowledge about the disease has progressed extraordinarily, this has not been accompanied by our capacity to effectively treat the disease. In the last years, immunotherapy made its way into the cancer field and was responsible for major changes in the treatment success rates for several cancer types. Although gastric cancer was not among the first successful targets of this type of therapy, the relationship between this type of cancer, immunosurveillance and immunotherapy is now being actively researched. In this article, we review the literature of the past year regarding the relationship between gastric cancer, its immune microenvironment and response to immunotherapy. Published data indicate that the immune microenvironment influences the clinical behaviour of gastric cancer, and is correlated with its histologic and molecular subtypes with an emphasis on the microsatellite- and EBV-positive tumour subgroups. Although the literature regarding response to immunotherapy is scarce, there is good evidence that patient stratification for immunotherapy is going to become a reality in gastric cancer.


Asunto(s)
Inmunoterapia , Neoplasias Gástricas/terapia , Microambiente Tumoral/inmunología , Humanos
10.
BMC Cancer ; 19(1): 771, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31382922

RESUMEN

BACKGROUND: Long non-coding RNAs (lncRNAs) represent a substantial portion of the human transcriptome. LncRNAs present a very stringent cell-type/tissue specificity being potential candidates for therapeutical applications during aging and disease. As example, targeting of MALAT1, a highly conserved lncRNA originally identified in metastatic non-small cell lung cancer, has shown promising results in cancer regression. Nevertheless, the regulation and specificity of MALAT1 have not been directly addressed. Interestingly, MALAT1 locus is spanned by an antisense transcript named TALAM1. METHODS: Here using a collection of breast cancer cells and in vitro and in vivo migration assays we characterized the dynamics of expression and demonstrated that TALAM1 regulates and synergizes with MALAT1 during tumorigenesis. RESULTS: Down-regulation of TALAM1 was shown to greatly impact on the capacity of breast cancer cells to migrate in vitro or to populate the lungs of immunocompromised mice. Additionally, we demonstrated that TALAM1 cooperates with MALAT1 in the regulation of the properties guiding breast cancer aggressiveness and malignancy. CONCLUSIONS: By characterizing this sense/anti-sense pair we uncovered the complexity of MALAT1 locus regulation, describing new potential candidates for cancer targeting.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , ARN sin Sentido/genética , ARN Largo no Codificante/genética , Transcripción Genética/genética , Animales , Carcinogénesis/genética , Movimiento Celular , Proliferación Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Pulmón/patología , Células MCF-7 , Ratones , Ratones SCID , Metástasis de la Neoplasia , Transfección , Trasplante Heterólogo , Regulación hacia Arriba/genética
11.
Conserv Biol ; 33(5): 1023-1034, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31209924

RESUMEN

Ecological distance-based spatial capture-recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner.


Diseño de Reservas para Optimizar la Conectividad Funcional y la Densidad Animal Resumen Los modelos de captura-recaptura espacial (CRE) basados en distancias ecológicas son un método prometedor para estimar la densidad animal y la conectividad, las cuales afectan los procesos poblacionales espaciales y, en última instancia, la persistencia de las especies. Exploramos cómo se puede integrar a los modelos CRE en los marcos de diseño de reserva que explícitamente reconocen tanto la distribución espacial de los individuos como su uso del espacio resultante de la estructura del paisaje. Formulamos el diseño de reservas de vida silvestre como un problema de optimización de presupuesto limitado y realizamos una simulación para explorar 3 diferentes objetivos de optimización informados por CRE que priorizaron diferentes metas de conservación mediante la maximización del número de individuos protegidos; la conectividad de la reserva y la conectividad ponderada por la densidad. También estudiamos el efecto sobre nuestros objetivos de hacer que los requerimientos individuales de uso de espacio fuesen satisfechos por la reserva de manera que se pudiese considerar que los individuos estaban protegidos (referidos como restricciones de rango de hogar). La maximización de la densidad de la población local resultó en reservas fragmentadas que probablemente no contribuyan a la persistencia de la población a largo plazo, mientras que la maximización de la conectividad produjo reservas que protegían al menor número de individuos. Sin embargo, la maximización de la conectividad ponderada por la densidad o la imposición preventiva de restricciones de rango de hogar en el diseño de reservas produjo reservas compuestas por conjuntos de parcelas mayormente compactas espacialmente que cubrían áreas de densidad alta en el paisaje con alta conectividad funcional entre ellas. Nuestros resultados cuantifican la extensión a la cual el diseño de reservas esta limitado por los requerimientos de rango de hogar individuales y resaltan que la consideración del uso de espacio individual en el objetivo y limitaciones puede ayudar al diseño de reservas que equilibren la abundancia y la conectividad de manera biológicamente relevante.


Asunto(s)
Conservación de los Recursos Naturales , Modelos Teóricos , Animales , Ecosistema , Densidad de Población
12.
Conserv Biol ; 31(1): 192-202, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27677418

RESUMEN

Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least-expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade-offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement-potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs and by allowing derived corridors to more closely reflect conservation priorities.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Ecología , Ecosistema , Montana
13.
Cell Tissue Res ; 366(3): 639-649, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27595150

RESUMEN

Male/female differences in enzyme activity and gene expression in the liver are known to be attenuated with ageing. Nevertheless, the effect of ageing on liver structure and quantitative cell morphology remains unknown. Male and female Wistar rats aged 2, 6, 12 and 18 months were examined by means of stereological techniques and immunohistochemical tagging of hepatocytes (HEP), liver sinusoidal endothelial cells (LSEC), Kupffer cells (KC) and hepatic stellate cells (HSC) in order to assess the total number and number per gram of these cells throughout life. The mean cell volume of HEP and HSC, the lobular position and the collagen content of the liver were also evaluated with stereological techniques. The number per gram of HSC was similar for both genders and was maintained throughout ageing. The mean volume of HSC was also conserved but differences in the cell body and lobular location were observed. Statistically significant gender differences in HEP were noted in young rats (females had smaller and more binucleated HEP) but were attenuated with ageing. The same occurred for KC and LSEC, since the higher number per gram in young females disappeared in older animals. Liver collagen increased with ageing but only in males. Thus, the numbers of these four cell types are related throughout ageing, with well-defined cell ratios. The shape and lobular position of HSC change with ageing in both males and females. Gender dimorphism in HEP, KC and LSEC of young rat liver disappears with ageing.


Asunto(s)
Envejecimiento/fisiología , Células Endoteliales/citología , Células Estrelladas Hepáticas/citología , Hepatocitos/citología , Inmunohistoquímica/métodos , Hígado/citología , Animales , Recuento de Células , Colágeno/metabolismo , Femenino , Masculino , Ratas Wistar
14.
J Anat ; 228(6): 996-1005, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26892301

RESUMEN

There is long-standing evidence that male and female rat livers differ in enzyme activity. More recently, differences in gene expression profiling have also been found to exist; however, it is still unclear whether there is morphological expression of male/female differences in the normal liver. Such differences could help to explain features seen at the pathological level, such as the greater regenerative potential generally attributed to the female liver. In this paper, hepatocytes (HEP), Kupffer cells (KC) and hepatic stellate cells (HSC) of male and female rats were examined to investigate hypothesised differences in number, volume and spatial co-localisation of these cell types. Immunohistochemistry and design-based stereology were used to estimate total numbers, numbers per gram and mean cell volumes. The position of HSC within lobules (periportal vs. centrilobular) and their spatial proximity to KC was also assessed. In addition, flow cytometry was used to investigate the liver ploidy. In the case of HEP and KC, differences in the measured cell parameters were observed between male and female specimens; however, no such differences were detected for HSC. Female samples contained a higher number of HEP per gram, with more binucleate cells. The HEP nuclei were smaller in females, which was coincident with more abundant diploid particles in these animals. The female liver also had a greater number of KC per gram, with a lower percentage of KC in the vicinity of HSC compared with males. In this study, we document hitherto unknown morphological sexual dimorphism in the rat liver, namely in HEP and KC. These differences may account for the higher regenerative potential of the female liver and lend weight to the argument for considering the rat liver as a sexually dimorphic organ.


Asunto(s)
Células Estrelladas Hepáticas , Hepatocitos , Macrófagos del Hígado , Hígado/citología , Caracteres Sexuales , Animales , Femenino , Citometría de Flujo , Masculino , Ratas Wistar
15.
Mol Pharm ; 13(2): 344-56, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26702499

RESUMEN

Splice switching oligonucleotides (SSOs) are a class of single-stranded antisense oligonucleotides (ssONs) being used as gene therapeutics and demonstrating great therapeutic potential. The availability of biodegradable and biocompatible delivery vectors that could improve delivery efficiencies, reduce dosage, and, in parallel, reduce toxicity concerns could be advantageous for clinical translation. In this work we explored the use of quaternized amphiphilic chitosan-based vectors in nanocomplex formation and delivery of splice switching oligonucleotides (SSO) into cells, while providing insights regarding cellular uptake of such complexes. Results show that the chitosan amphiphilic character is important when dealing with SSOs, greatly improving colloidal stability under serum conditions, as analyzed by dynamic light scattering, and enhancing cellular association. Nanocomplexes were found to follow an endolysosomal route with a long lysosome residence time. Conjugation of a hydrophobic moiety, stearic acid, to quaternized chitosan was a necessary condition to achieve transfection, as an unmodified quaternary chitosan was completely ineffective. We thus demonstrate that amphiphilic quaternized chitosan is a biomaterial that holds promise and warrants further development as a platform for SSO delivery strategies.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Quitosano/química , Nanopartículas/química , Oligonucleótidos Antisentido/farmacología , Empalme del ARN , Quitosano/administración & dosificación , Dispersión Dinámica de Luz , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Nanopartículas/administración & dosificación , Oligonucleótidos Antisentido/química , Oligonucleótidos Antisentido/genética
16.
BMC Vet Res ; 10: 101, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24774444

RESUMEN

BACKGROUND: Transmission models can aid understanding of disease dynamics and are useful in testing the efficiency of control measures. The aim of this study was to formulate an appropriate stochastic Susceptible-Infectious-Resistant/Carrier (SIR) model for Salmonella Typhimurium in pigs and thus estimate the transmission parameters between states. RESULTS: The transmission parameters were estimated using data from a longitudinal study of three Danish farrow-to-finish pig herds known to be infected. A Bayesian model framework was proposed, which comprised Binomial components for the transition from susceptible to infectious and from infectious to carrier; and a Poisson component for carrier to infectious. Cohort random effects were incorporated into these models to allow for unobserved cohort-specific variables as well as unobserved sources of transmission, thus enabling a more realistic estimation of the transmission parameters. In the case of the transition from susceptible to infectious, the cohort random effects were also time varying. The number of infectious pigs not detected by the parallel testing was treated as unknown, and the probability of non-detection was estimated using information about the sensitivity and specificity of the bacteriological and serological tests. The estimate of the transmission rate from susceptible to infectious was 0.33 [0.06, 1.52], from infectious to carrier was 0.18 [0.14, 0.23] and from carrier to infectious was 0.01 [0.0001, 0.04]. The estimate for the basic reproduction ration (R0) was 1.91 [0.78, 5.24]. The probability of non-detection was estimated to be 0.18 [0.12, 0.25]. CONCLUSIONS: The proposed framework for stochastic SIR models was successfully implemented to estimate transmission rate parameters for Salmonella Typhimurium in swine field data. R0 was 1.91, implying that there was dissemination of the infection within pigs of the same cohort. There was significant temporal-cohort variability, especially at the susceptible to infectious stage. The model adequately fitted the data, allowing for both observed and unobserved sources of uncertainty (cohort effects, diagnostic test sensitivity), so leading to more reliable estimates of transmission parameters.


Asunto(s)
Modelos Biológicos , Salmonelosis Animal/microbiología , Salmonella typhimurium/fisiología , Enfermedades de los Porcinos/microbiología , Animales , Teorema de Bayes , Portador Sano , Salmonelosis Animal/transmisión , Porcinos , Enfermedades de los Porcinos/transmisión
17.
BMC Vet Res ; 10: 140, 2014 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-24965915

RESUMEN

BACKGROUND: The impact of non-commercial producers on disease spread via livestock movement is related to their level of interaction with other commercial actors within the industry. Although understanding these relationships is crucial in order to identify likely routes of disease incursion and transmission prior to disease detection, there has been little research in this area due to the difficulties of capturing movements of small producers with sufficient resolution. Here, we used the Scottish Livestock Electronic Identification and Traceability (ScotEID) database to describe the movement patterns of different pig production systems which may affect the risk of disease spread within the swine industry. In particular, we focused on the role of small pig producers. RESULTS: Between January 2012 and May 2013, 23,169 batches of pigs were recorded moving animals between 2382 known unique premises. Although the majority of movements (61%) were to a slaughterhouse, the non-commercial and the commercial sectors of the Scottish swine industry coexist, with on- and off-movement of animals occurring relatively frequently. For instance, 13% and 4% of non-slaughter movements from professional producers were sent to a non-assured commercial producer or to a small producer, respectively; whereas 43% and 22% of movements from non-assured commercial farms were sent to a professional or a small producer, respectively. We further identified differences between producer types in several animal movement characteristics which are known to increase the risk of disease spread. Particularly, the distance travelled and the use of haulage were found to be significantly different between producers. CONCLUSIONS: These results showed that commercial producers are not isolated from the non-commercial sector of the Scottish swine industry and may frequently interact, either directly or indirectly. The observed patterns in the frequency of movements, the type of producers involved, the distance travelled and the use of haulage companies provide insights into the structure of the Scottish swine industry, but also highlight different features that may increase the risk of infectious diseases spread in both Scotland and the UK. Such knowledge is critical for developing more robust biosecurity and surveillance plans and better preparing Scotland against incursions of emerging swine diseases.


Asunto(s)
Crianza de Animales Domésticos/métodos , Porcinos/fisiología , Mataderos , Animales , Vehículos a Motor , Escocia , Transportes
18.
Exp Appl Acarol ; 64(2): 259-63, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24696361

RESUMEN

Brazil harbors five species of Cypseloidinae swifts. Those from Streptoprocne and Cypseloides genera have a very distinct ecology. They shelter at night and build nests in moist cliffs by waterfalls. Information about tick infestation of these birds is virtually non-existent and restricted to the description of a new species, Ixodes paranaensis, in Streptoprocne biscutata in Paraná State and another record of this species in Streptoprocne zonaris in Minas Gerais State. We herein report tick infestation of swifts at eight waterfalls in the Cerrado biome of Minas Gerais State, southeastern Brazil. Swifts were captured during six campaigns from November 2008 to April 2013. Overall, 584 swifts were captured (527 C. senex, four C. fumigatus and 53 S. zonaris). Four birds were tick infested (prevalence of 0.7 %). Three individuals of C. senex hosted one tick each; a nymph of I. paranaensis, a female of I. paranaensis and a nymph of Amblyomma cajennense. One S. zonaris hosted an I. paranaensis nymph and an Ornithodoros sp. larva (Argasidae).


Asunto(s)
Enfermedades de las Aves/parasitología , Ixodidae/clasificación , Infestaciones por Garrapatas/veterinaria , Animales , Enfermedades de las Aves/epidemiología , Aves , Brasil/epidemiología , Femenino , Especificidad de la Especie , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
19.
Pharm Dev Technol ; 19(2): 173-80, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23356908

RESUMEN

Ethylcellulose microparticles containing metronidazole and propolis extractive solution were prepared and evaluated in vitro against periodontal pathogens. Scanning electron microscopy, particle size analysis, drug entrapment efficiency and drug release of microparticles were determined. The antimicrobial activity of microparticles was evaluated against microorganisms of periodontal importance (Enterococcus faecalis, Streptococcus pyogenes, Streptococcus mutans, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli). It was obtained particles with regular morphology, mean diameter of 1.23 µm, and entrapment efficiency for propolis and metronidazole were 91.41% and 22.23%, respectively. In vitro release studies of propolis and metronidazole from microparticles showed prolonged drug release and controlled by Fickian diffusion. Both propolis and metronidazole displayed activity against the tested strains. Moreover, the results showed that the strains of E. faecalis, S. pyogenes and S. mutans were more susceptible to the propolis and E. faecalis to the metronidazole. It was also observed that the amount of metronidazole to inhibit the microorganism strains in the physical mixture with propolis was smaller than in the metronidazole alone, suggesting potentiation effect between propolis and metronidazole. These microparticles would be useful for developing intermediary or eventual dosage form to be administered into the periodontal pocket more easily and safely.


Asunto(s)
Antiinfecciosos/administración & dosificación , Bacterias/efectos de los fármacos , Celulosa/análogos & derivados , Portadores de Fármacos/química , Metronidazol/administración & dosificación , Própolis/administración & dosificación , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Escherichia coli/efectos de los fármacos , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Própolis/farmacología , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos
20.
J Med Radiat Sci ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888376

RESUMEN

INTRODUCTION: Renal Point-of-Care Ultrasound (POCUS) is a screening modality that aids in clinical decision-making for patients with suspected renal colic. This study intends to compare the accuracy and pertinence of sonographic findings obtained by a sonographer in a Basic Emergency Service (BES) with the imaging findings at the Referral Hospital (RH). METHODS: Thirty-one patients suspected of having renal pathology underwent initial sonography screening with POCUS at the BES and were subsequently referred to the RH for additional imaging examinations. The results of both examinations were compared to verify whether the findings from the BES were confirmed by the radiologist in the RH and to ensure that the patient referrals from BES to RH were appropriate. RESULTS: In our sample, the majority of patients (80%) exhibited varying degrees of pyelocaliceal distension, with nearly half (48%) patients presenting obstructions. A strong association between the sonographic findings in the BES and the RH was found in the variables 'Dilatation of pyelocaliceal system' (V = 0.895; P = 0.00), 'Simple cystic formation' (V = 0.878; P = 0.000), respectively. There was a statistically significant correlation between BES and RH findings, indicating a strong association between these two variables, respectively (k = 0.890; P = 0.000) and (k = 0.870; P = 0.000). There was also a strong statistically significant correlation in the ultrasonographic findings between BES and RH performers (k = 0.890; P = 0.000 and k = 0.870; P = 0.000). In this research, an achieved sensitivity of 96% and a specificity of 85% were demonstrated in the identification of pyelocaliceal dilatation. CONCLUSION: Renal POCUS screening successfully detected abnormalities in the urinary system of patients suspected of having renal colic. The sonographic findings at the BES had a good correlation with the complementary imaging results obtained at the RH in Portugal. These results suggest that Radiographers/Sonographers can have an important role in the preliminary assessment of urgent renal pathology in remote areas, contributing to a correct referral and early treatment.

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