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1.
Clin Exp Dermatol ; 46(8): 1530-1541, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34115900

RESUMEN

BACKGROUND: Early and accurate diagnosis of cutaneous squamous cell carcinomas (SCCs) and actinic keratoses (AK) is fundamental to reduce their associated morbidity and to select the correct treatment. Line-field confocal optical coherence tomography (LC-OCT) is a new imaging device that can characterize healthy skin and basal cell carcinoma, but no large studies on keratinocyte cell tumours have yet been published. AIM: To identify and describe LC-OCT criteria associated with SCC and AK, and to compare LC-OCT findings in these tumours. METHODS: A retrospective observational multicentre study was conducted. Lesions were imaged with the LC-OCT device before surgery and examined histologically. LC-OCT criteria for AK/SCC were identified and their presence was evaluated in all study lesions. Univariate and multivariate analyses were performed to compare AK and SCCs, and to investigate differences between in situ and invasive tumours. RESULTS: In total, 158 patients with 50 AK and 108 SCCs (62 in situ and 46 invasive) were included. Cytological and architectural alterations were found in most lesions, and differences were found between AK and SCCs. Although the visualization of the dermoepidermal junction (DEJ) was often hampered by hyperkeratosis and acanthosis, an outlined DEJ without broad strands was observed in almost all AK and almost all in situ SCCs, but in only three invasive SCCs (P < 0.001) when the DEJ was detectable. CONCLUSION: Our results suggest that LC-OCT can help clinicians in the identification of AK and SCC and their differentiation, providing a real-time and noninvasive examination. Further studies are needed to confirm our data.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Queratosis Actínica/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Diagnóstico Diferencial , Femenino , Humanos , Queratosis Actínica/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Cutáneas/patología
2.
J Eur Acad Dermatol Venereol ; 35(5): 1099-1110, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33398911

RESUMEN

BACKGROUND: Early diagnosis and subtype classification of basal cell carcinoma (BCC) are crucial to reduce morbidity and optimize treatment. Good accuracy in differentiating BCC from clinical imitators has been achieved with existing diagnostic strategies but lower performance in discriminating BCC subtypes. Line-field confocal optical coherence tomography (LC-OCT) is a new technology able to combine the technical advantages of reflectance confocal microscopy and OCT. OBJECTIVES: To identify and describe LC-OCT criteria associated with BCC and explore their association with BCC subtypes. METHODS: Basal cell carcinoma were imaged with a handheld LC-OCT device before surgical excision. LC-OCT images were retrospectively evaluated by three observers for presence/absence of criteria for BCC. Multivariate logistic regression models were used to find independent predictors of BCC subtypes. RESULTS: Eighty-nine histopathologically proven BCCs were included, of which 66 (74.2%) were pure subtypes [superficial BCC (sBCC): 19/66 (28.8%); nodular BCC (nBCC): 31/66 (47.0%); infiltrative BCC (iBCC): 16/66 (24.2%)]. Lobules, blood vessels and small bright cells within epidermis/lobules were the most frequent criteria for BCC. LC-OCT criteria independently associated with sBCC were presence of hemispheric lobules, absence of lobule separation from the epidermis, absence of stretching of the stroma; with nBCC were presence of macrolobules, absence of lobule connection to the epidermis; and with iBCC were presence of branched lobules. CONCLUSIONS: This was the first study describing the characteristics of BCC under LC-OCT examination. We proposed morphologic criteria, which could be potentially useful for diagnosis and subtype classification of BCC, as well as for its therapeutic management. Future studies are needed to assess these hypotheses.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Carcinoma Basocelular/diagnóstico por imagen , Humanos , Microscopía Confocal , Estudios Retrospectivos , Neoplasias Cutáneas/diagnóstico por imagen , Tomografía de Coherencia Óptica
3.
J Eur Acad Dermatol Venereol ; 34(12): 2914-2921, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32786124

RESUMEN

BACKGROUND: Line-field confocal optical coherence tomography (LC-OCT) is a non-invasive optical technique recently developed for skin examination in vivo. It provides real-time, high-resolution vertical images with an isotropic resolution of ~1 µm and a penetration depth of ~500 µm. OBJECTIVES: Study goals were to qualitatively/quantitatively characterize healthy skin at different body sites using LC-OCT. METHODS: The skin of young healthy volunteers was imaged with a handheld LC-OCT imaging device. Seven body sites (back of the hand, forehead, cheek, nose, chest, forearm and back) were investigated. An independent qualitative [cutaneous structures' description; visibility of keratinocytes' nuclei and dermal-epidermal junction (DEJ)] and quantitative [stratum corneum (SC)/epidermal thicknesses; height of dermal papillae] assessment of the LC-OCT images was performed. RESULTS: A total of 88 LC-OCT images were collected from 29 participants (20 females; nine males; mean age 25.9 years). Keratinocytes' nuclei and DEJ were visible in the totality of images. The different layers of the epidermis and the remaining cutaneous structures/findings were visualized. Body sites-related variability was detected for SC/epidermal thicknesses and height of dermal papillae. Inter-observer agreement was excellent (SC thickness), good-to-excellent (epidermal thickness) and moderate-to-good (papillae). CONCLUSIONS: Line-field confocal-OCT provides non-invasive, real-time imaging of the skin in vivo with deep penetration and high resolution, enabling the visualization of single cells. The histology-like vertical view provides an easy way to recognize/measure different cutaneous structures/findings. LC-OCT appears as a promising technique for the examination of physiological/pathological skin.


Asunto(s)
Piel , Tomografía de Coherencia Óptica , Adulto , Epidermis , Femenino , Técnicas Histológicas , Humanos , Queratinocitos , Masculino , Piel/diagnóstico por imagen
4.
Cell Immunol ; 329: 10-16, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29661473

RESUMEN

Silk fibroin is a novel biomaterial for enhancing transplanted islet cell function and survival. This study investigated whether silk fibroin may have unique properties that improve islet function in the face of inflammatory-mediated stress during transplantation. Murine islet function was tested in vitro with either silk fibroin or alginate and challenged with inflammatory cytokines. The glucose-stimulated insulin secretion index for all conditions decreased with inflammatory cytokines, but was better preserved for islets exposed to silk compared to those exposed to alginate or medium. GLUT2 transporter expression on the cell surface of islets exposed to silk was increased compared to alginate or medium alone. Upon cytokine stress, a greater percentage of islet cells exposed to silk expressed GLUT2 on their surface. We conclude that preconditioning islets with silk fibroin stimulates islet cell surface GLUT2 expression, an increase, which persists under inflammatory stress, and may improve islet engraftment and function after transplantation.


Asunto(s)
Fibroínas/metabolismo , Fibroínas/farmacología , Islotes Pancreáticos/efectos de los fármacos , Alginatos/farmacología , Animales , Fibroínas/fisiología , Transportador de Glucosa de Tipo 2/genética , Transportador de Glucosa de Tipo 2/metabolismo , Inflamación , Células Secretoras de Insulina/efectos de los fármacos , Islotes Pancreáticos/fisiología , Trasplante de Islotes Pancreáticos/métodos , Trasplante de Islotes Pancreáticos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Seda/fisiología , Estrés Fisiológico/efectos de los fármacos
5.
Br J Surg ; 105(5): 502-511, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29603130

RESUMEN

BACKGROUND: Up to 40 per cent of patients undergoing oesophagectomy develop pneumonia. The aim of this study was to assess whether preoperative inspiratory muscle training (IMT) reduces the rate of pneumonia after oesophagectomy. METHODS: Patients with oesophageal cancer were randomized to a home-based IMT programme before surgery or usual care. IMT included the use of a flow-resistive inspiratory loading device, and patients were instructed to train twice a day at high intensity (more than 60 per cent of maximum inspiratory muscle strength) for 2 weeks or longer until surgery. The primary outcome was postoperative pneumonia; secondary outcomes were inspiratory muscle function, lung function, postoperative complications, duration of mechanical ventilation, length of hospital stay and physical functioning. RESULTS: Postoperative pneumonia was diagnosed in 47 (39·2 per cent) of 120 patients in the IMT group and in 43 (35·5 per cent) of 121 patients in the control group (relative risk 1·10, 95 per cent c.i. 0·79 to 1·53; P = 0·561). There was no statistically significant difference in postoperative outcomes between the groups. Mean(s.d.) maximal inspiratory muscle strength increased from 76·2(26·4) to 89·0(29·4) cmH2 O (P < 0·001) in the intervention group and from 74·0(30·2) to 80·0(30·1) cmH2 O in the control group (P < 0·001). Preoperative inspiratory muscle endurance increased from 4 min 14 s to 7 min 17 s in the intervention group (P < 0·001) and from 4 min 20 s to 5 min 5 s in the control group (P = 0·007). The increases were highest in the intervention group (P < 0·050). CONCLUSION: Despite an increase in preoperative inspiratory muscle function, home-based preoperative IMT did not lead to a decreased rate of pneumonia after oesophagectomy. Registration number: NCT01893008 (https://www.clinicaltrials.gov).


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagectomía , Terapia por Ejercicio/métodos , Neumonía/prevención & control , Complicaciones Posoperatorias/prevención & control , Cuidados Preoperatorios/métodos , Músculos Respiratorios/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Neumonía/epidemiología , Complicaciones Posoperatorias/epidemiología , Método Simple Ciego , Resultado del Tratamiento
6.
J Appl Microbiol ; 125(3): 686-699, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29777634

RESUMEN

AIMS: The aims of the current study were to characterize the outer membrane proteins (OMPs) of Francisella noatunensis subsp. orientalis (Fno) STIR-GUS-F2f7, and identify proteins recognized by sera from tilapia, Oreochromis niloticus, (L) that survived experimental challenge with Fno. METHODS AND RESULTS: The composition of the OMPs of a virulent strain of Fno (STIR-GUS-F2f7), isolated from diseased red Nile tilapia in the United Kingdom, was examined. The sarcosine-insoluble OMPs fraction was screened with tilapia hyperimmune sera by western blot analysis following separation of the proteins by 1D SDS-PAGE. Liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was used to identify the various proteins present in the OMP profile. Two hundred and thirty-nine proteins were identified, of which 44 were found in the immunogenic band recognized by the tilapia hyperimmune serum. In silico analysis was performed to predict the function and location of the OMPs identified by MS. CONCLUSIONS: Using a powerful proteomic-based approach in conjugation with western immunoblotting, proteins comprising the outer membrane fraction of Fno STIR-GUS-F2f7 were identified, catalogued and screened for immune recognition by tilapia sera. SIGNIFICANCE AND IMPACT OF THE STUDY: The current study is the first report on the characterization of Fno-OMPs. The findings here provide preliminary data on bacterial surface proteins that exist in direct contact with the host's immune defences during infection and offer an insight into the pathogenesis of Fno.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa , Francisella , Proteoma , Animales , Proteínas de la Membrana Bacteriana Externa/análisis , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/clasificación , Cíclidos/microbiología , Enfermedades de los Peces/microbiología , Francisella/química , Francisella/patogenicidad , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Proteoma/análisis , Proteoma/química , Proteoma/clasificación , Tilapia/microbiología
7.
Bull Entomol Res ; 108(2): 213-222, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28891460

RESUMEN

Cixiid planthoppers are considered of major economic importance, as they can transmit phytoplasmas responsible for many plant diseases. While thorougly studied in vineyards, the epidemiology of stolbur phytoplasma, transmitted by Hyalesthes obsoletus Signoret, was rarely investigated on minor crops as lavender, where it leads to 'yellow decline' disease and large economic losses. The objective of this paper is to understand the effect of the local landscape characteristics on the presence and density of H. obsoletus in the 'Plateau de Valensole', southern France. Potential host plants of H. obsoletus were surveyed in three contrasted zones (in terms of crops and disease intensity), by uprooting plants and capturing adults in emergence traps. The localization and potential movements of H. obsoletus from the host plants towards lavandin (infertile hybrid of lavender) were determined using yellow sticky traps. Clary sage plants were found as major hosts of H. obsoletus. Flying insects were also caught in fields of lavandin, although emergence traps and plant uprooting did not confirm this crop as a winter host, i.e., as a reservoir for the insect. Based on one zone, we showed that attractiveness may depend on crop (clary sage or lavandin) and on its age, as well as on the distance to the supposed source field. These results suggest that clary sage could be an important host of H. obsoletus, whose density largely varies between zones. Genetic studies would be required to confirm the role of clary sage in the dissemination of yellow decline of lavandin.


Asunto(s)
Hemípteros , Herbivoria , Insectos Vectores , Animales , Larva
8.
Heredity (Edinb) ; 119(6): 402-410, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28930289

RESUMEN

Historical fluctuations in forests' distribution driven by past climate changes and anthropogenic activities can have large impacts on the demographic history of pathogens that have a long co-evolution history with these host trees. Using a population genetic approach, we investigated that hypothesis by reconstructing the demographic history of Armillaria ostoyae, one of the major pathogens of the maritime pine (Pinus pinaster), in the largest monospecific pine planted forest in Europe (south-western France). Genetic structure analyses and approximate Bayesian computation approaches revealed that a single pathogen population underwent a severe reduction in effective size (12 times lower) 1080-2080 generations ago, followed by an expansion (4 times higher) during the last 4 generations. These results are consistent with the history of the maritime pine forest in the region characterized by a strong recession during the last glaciation (~19 000 years ago) and massive plantations during the second half of the nineteenth century. Results suggest that recent and intensive plantations of a host tree population have offered the opportunity for a rapid spread and adaptation of their pathogens.


Asunto(s)
Armillaria/genética , Genética de Población , Pinus/microbiología , Enfermedades de las Plantas/microbiología , Armillaria/patogenicidad , Teorema de Bayes , Bosques , Francia , Pool de Genes , Técnicas de Genotipaje , Repeticiones de Microsatélite , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Densidad de Población , Árboles/microbiología
9.
Adv Mar Biol ; 75: 333-358, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27770989

RESUMEN

The harbour porpoise, Phocoena phocoena, is one of the best studied cetacean species owing to its common distribution along the coastal waters of the Northern Hemisphere. In European waters, strandings are common and bycatch mortalities in commercial fisheries reach alarming numbers. Lethal interactions resulting from human activities together with ongoing environmental changes raise serious concerns about population viability throughout the species' range. These concerns foster the need to fill critical gaps in knowledge of harbour porpoise biology, including population structure, feeding ecology, habitat preference and evolutionary history, that are critical information for planning effective management and conservation efforts. While the species is distributed fairly continuously in the North Atlantic Ocean, it becomes fragmented in the south-eastern part with isolated populations occurring along the Atlantic coasts of the Iberian Peninsula, Northwest Africa and the Black Sea. The latter population is separated from Atlantic populations by the Mediterranean Sea, where the species is almost entirely absent. Understanding the evolutionary history of these populations occurring in marginal habitats holds the potential to reveal fundamental aspects of the species' biology such as the factors determining its distribution, ecological niche, and how past and recent environmental variation have shaped the current population structure. This information can be critical for understanding the future evolution of the species in consideration of ongoing environmental changes. This chapter summarizes the recent advances in our knowledge regarding the populations bordering the Mediterranean Sea with a special emphasis on their ecological and evolutionary history, which has recently been reconstructed from genetic analyses.


Asunto(s)
Evolución Biológica , Phocoena/fisiología , Distribución Animal , Animales , Océano Atlántico , Mar Mediterráneo , Phocoena/genética , Filogeografía
10.
J Fish Dis ; 39(1): 13-29, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25399660

RESUMEN

Streptococcus agalactiae infections in fish are predominantly caused by beta-haemolytic strains of clonal complex (CC) 7, notably its namesake sequence type (ST) 7, or by non-haemolytic strains of CC552, including the globally distributed ST260. In contrast, CC23, including its namesake ST23, has been associated with a wide homeothermic and poikilothermic host range, but never with fish. The aim of this study was to determine whether ST23 is virulent in fish and to identify genomic markers of fish adaptation of S. agalactiae. Intraperitoneal challenge of Nile tilapia, Oreochromis niloticus (Linnaeus), showed that ST260 is lethal at doses down to 10(2) cfu per fish, whereas ST23 does not cause disease at 10(7) cfu per fish. Comparison of the genome sequence of ST260 and ST23 with those of strains derived from fish, cattle and humans revealed the presence of genomic elements that are unique to subpopulations of S. agalactiae that have the ability to infect fish (CC7 and CC552). These loci occurred in clusters exhibiting typical signatures of mobile genetic elements. PCR-based screening of a collection of isolates from multiple host species confirmed the association of selected genes with fish-derived strains. Several fish-associated genes encode proteins that potentially provide fitness in the aquatic environment.


Asunto(s)
Cíclidos , Enfermedades de los Peces/microbiología , Genoma Bacteriano , Infecciones Estreptocócicas/veterinaria , Streptococcus agalactiae/patogenicidad , Animales , Bovinos , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , Sitios Genéticos/genética , Humanos , Filogenia , Phocidae/microbiología , Pase Seriado/veterinaria , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/genética , Virulencia
11.
Hist Sci Med ; 48(4): 469-74, 2014.
Artículo en Francés | MEDLINE | ID: mdl-25962214

RESUMEN

Chemotherapy stands today for cancer. In 1909, Paul Ehrlich (1854-1915) advocates the use of arsphenamine by infusion. So, he is considered as the father of chemotherapy. In fact, the first to have thought through chemotherapy was Sir Christopher Wren (1632-1723). In 1676, ideas and experiments on animals had sufficiently progressed to allow Michel Ettmuller (1644-1683) to publish the first edition of his book and several others were printed until 1753. In this book, he describes the first intravenous treatment, it sets the first indications, dosages and different products which can be used. However this method has been forgotten until the late 19th century.


Asunto(s)
Antineoplásicos/historia , Neoplasias/historia , Administración Intravenosa , Animales , Antineoplásicos/administración & dosificación , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Neoplasias/tratamiento farmacológico
12.
Ann Burns Fire Disasters ; 37(2): 143-147, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38974795

RESUMEN

The objective of this study is to assess the quality of life and how to return to work after burns in adults. We conducted a monocentric, observational, prospective and open study in an intensive care burn unit. Patients aged between 18 and 65 years old were enrolled. Quality of life was assessed with Burn Specific Health Scale-Brief (BSHS-B). A total 118 patients were included with one delayed death. There were 55 flame burns. Median age was 39 years, median total burn surface area (TBSA) was 5% and median length of stay was 11 days. After management in the intensive care burn unit, 84 patients were discharged home and 33 to a rehabilitation care department. We sent 117 queries and got 56 answers. Median BSHS-B score ratio was 142/160. The most impacted items were heat sensitivity, body image, treatment regimens and work. Simple abilities were also affected with up to 28% of patients having difficulties with everyday actions such as cleaning oneself. Regarding return to work, 32% of workers lost their full-time job and 18% were downgraded as disabled. The outcome was worse for those patients who had to go to rehabilitation. Our data suggest that even small burns may strongly impact quality of life and limit the ability to return to work. Our results are consistent with previous published studies, which found greater alteration of quality of life with larger TBSA. These results call for care in specialized centers even for limited burns, especially in the case of functional area involvement.


Le but de ce travail est d'évaluer la qualité de vie et le retour au travail après brûlure chez des adultes. Il s'agit d'une étude monocentrique, observationnelle, prospective et ouverte menée dans un CTB auprès de patients de 18 à 65 ans. La qualité de vie a été évaluée en utilisant l'échelle BSHS-B (Burn Specific Health Scale-Brief). Nous avons inclus 118 patients dont 55 brûlés par flamme, 1 d'entre eux est décédé secondairement. En médianes, l'âge était de 39 ans, la surface atteinte de 5 % et la durée de séjour de 11 jours. Après leur hospitalisation en USI, 84 patients sont rentrés chez eux et 33 ont été transférés en SMR. Nous avons reçu 56 réponses aux 117 questionnaires envoyés. Le BSHS-B médian était de 142/160. Les variables les plus impactées étaient la sensibilité à la chaleur, l'image corporelle, les contraintes liées au traitement et le travail. Vingt-huit pour cent des patients étaient gênés pour les actes de la vie courante comme l'hygiène corporelle. En ce qui concerne le travail, 32 % des patients avaient perdu leur emploi et 18 % étaient considérés comme des travailleurs handicapés. Les suites étaient pires chez les patients ayant eu besoin de rééducation. Cette étude suggère que même de petites brûlure peuvent retentir fortement sur la qualité de vie et limiter les capacités de travail, à l'instar d'études précédentes, qui s'intéressaient à des patients atteints sur de plus grandes surfaces. Ceci prouve la nécessité du traitement en CTB de patients même peu atteints, en particulier si une zone fonctionnelle est atteinte.

13.
Mol Ecol ; 22(2): 327-40, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23205613

RESUMEN

Unravelling the mechanisms involved in adaptation to understand plant morphological evolution is a challenging goal. For crop species, identification of molecular causal polymorphisms involved in domestication traits is central to this issue. Pearl millet, a domesticated grass mostly found in semi-arid areas of Africa and India, is an interesting model to address this topic: the domesticated form shares common derived phenotypes with some other cereals such as a decreased ability to develop basal and axillary branches in comparison with the wild phenotype. Two recent studies have shown that the orthologue of the maize gene Teosinte-Branched1 in pearl millet (PgTb1) was probably involved in branching evolution during domestication and that a miniature inverted-repeat transposable element (MITE) of the Tuareg family was inserted in the 3' untranslated region of PgTb1. For a set of 35 wild and domesticated populations, we compared the polymorphism patterns at this MITE and at microsatellite loci. The Tuareg insertion was nearly absent in the wild populations, whereas a strong longitudinal frequency cline was observed in the domesticated populations. The geographical pattern revealed by neutral microsatellite loci clearly demonstrated that isolation by distance does not account for the existence of this cline. However, comparison of population differentiation at the microsatellite and the MITE loci and analyses of the nucleotide polymorphism pattern in the downstream region of PgTb1 did not show evidence that the cline at the MITE locus has been shaped by selection, suggesting the implication of a neutral process. Alternative hypotheses are discussed.


Asunto(s)
Elementos Transponibles de ADN , Secuencias Invertidas Repetidas , Pennisetum/genética , Polimorfismo Genético , África , Productos Agrícolas/genética , ADN de Plantas/genética , Evolución Molecular , Genes de Plantas , Repeticiones de Microsatélite , Selección Genética , Análisis de Secuencia de ADN
14.
J Dairy Sci ; 96(2): 962-70, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23200465

RESUMEN

Streptococcus uberis causes clinical and subclinical mastitis in cattle and sheep, but it is unknown whether the composition of Strep. uberis populations differs between host species. To address this, we characterized a collection of bovine and ovine Strep. uberis isolates with shared geographical and temporal origins by means of an expanded multilocus sequence typing scheme. Among 14 ovine and 35 bovine isolates, 35 allelic profiles were detected. Each allelic profile was associated with a single host species and all but one were new to the multilocus sequence typing database. The median number of new alleles per isolate was higher for ovine isolates than for bovine isolates. None of the ovine isolates belonged to the global clonal complexes 5 or 143, which are commonly associated with bovine mastitis and which have a wide geographical distribution. Ovine isolates also differed from bovine isolates in carriage of plasminogen activator genes, with significantly higher prevalence of pauB in ovine isolates. Isolates that were negative for yqiL, one of the targets of multilocus sequence typing, were found among ovine and bovine isolates and were not associated with a specific sequence type or global clonal complex. One bovine isolate carried a gapC allele that was probably acquired through lateral gene transfer, most likely from Streptococcus salivarius. We conclude that ovine isolates are distinct from bovine isolates of Strep. uberis, and that recombination between isolates from different host species or bacterial species could contribute to changes in virulence gene profiles with relevance for vaccine development.


Asunto(s)
Streptococcus/genética , Animales , Bovinos/microbiología , ADN Bacteriano/genética , Femenino , Mastitis/microbiología , Mastitis/veterinaria , Mastitis Bovina/microbiología , Tipificación de Secuencias Multilocus/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Ovinos/microbiología , Enfermedades de las Ovejas/microbiología , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , Streptococcus/aislamiento & purificación
15.
J Dairy Sci ; 96(8): 5129-45, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23769372

RESUMEN

Streptococcus uberis is an important cause of intramammary infection in dairy cattle. Strains of Strep. uberis appear to differ in their ability to cause disease based on previous epidemiological studies. We explored the pathogenicity of 2 strains of Strep. uberis, where one strain represented a putatively host-adapted type based on its ability to cause persistent infection and to spread from cow to cow in a lactating herd. This type was part of a clonal complex that is commonly associated with bovine mastitis. The other strain, which was isolated from a transient infection in a single animal in the same herd and did not belong to any known clonal complex, was selected as putatively nonadapted type. Cows (6 per strain) were experimentally challenged in a single hind quarter and the adjacent hind quarter was used as mock challenged control quarter. Both strains showed an equal ability to grow in the milk of challenge animals in vitro. All cows that were challenged with the putatively host-adapted strain developed clinical signs of mastitis, including fever and milk yield depression as well as elevated somatic cell count due to influx of polymorphonuclear leucocytes and lymphocytes. The cytokine response followed a specific order, with an increase in IL-1ß, IL-6, and IL-8 levels at the time of first SCC elevation, followed by an increase in IL-10, IL-12p40, and tumor necrosis factor-α levels approximately 6h later. In 4 of 6 animals, IL-17A was detected in milk between 57 and 168 h postchallenge. The increase in IL-17A levels coincided with inversion of the prechallenge CD4(+)-to-CD8(+) T lymphocyte ratio, which was observed from 96 h postchallenge. This was followed by normalization of the CD4(+)-to-CD8(+) ratio due to continued increase of the CD8(+) concentration up to 312 h postchallenge. Spontaneous resolution of infection was observed in 5 animals and coincided with a measurable IL-17A response in 4 animals, suggesting that IL-17 may be involved in the resolution of intramammary infection. With the exception of minor elevation of IL-8 levels, no clinical, cytological, or immunological response was detected in quarters challenged with the nonadapted strain. The observed strain-specific pathogenicity was consistent across animals, implying that it is determined by pathogen factors rather than host factors.


Asunto(s)
Mastitis Bovina/microbiología , Infecciones Estreptocócicas/veterinaria , Streptococcus/patogenicidad , Animales , Bovinos , Recuento de Células/veterinaria , Electroforesis en Gel de Campo Pulsado/veterinaria , Femenino , Interleucina-17/sangre , Interleucina-1beta/sangre , Interleucina-6/sangre , Interleucina-8/sangre , Recuento de Linfocitos/veterinaria , Mastitis Bovina/inmunología , Leche/citología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Streptococcus/inmunología
16.
Mol Ecol ; 21(3): 715-31, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21988698

RESUMEN

Behaviour and genetic structure are intimately related: mating patterns and patterns of movement between groups or populations influence the movement of genetic variation across the landscape and from one generation to the next. In hybrid zones, the behaviour of the hybridizing taxa can also impact the incidence and outcome of hybridization events. Hybridization between yellow baboons and anubis baboons has been well documented in the Amboseli basin of Kenya, where more anubis-like individuals tend to experience maturational and reproductive advantages. However, it is unknown whether these advantages are reflected in the genetic structure of populations surrounding this area. Here, we used microsatellite genotype data to evaluate the structure and composition of baboon populations in southern Kenya. Our results indicate that, unlike for mitochondrial DNA, microsatellite-based measures of genetic structure concord with phenotypically based taxonomic distinctions and that the currently active hybrid zone is relatively narrow. Isolation with migration analysis revealed asymmetric gene flow in this region from anubis populations into yellow populations, in support of the anubis-biased phenotypic advantages observed in Amboseli. Populations that are primarily yellow but that receive anubis gene flow exhibit higher levels of genetic diversity than yellow populations far from the introgression front. Our results support previous work that indicates a long history of hybridization and introgression among East African baboons. Specifically, it suggests that anubis baboons are in the process of gradual range expansion into the range of yellow baboons, a pattern potentially explained by behavioural and life history advantages that correlate with anubis ancestry.


Asunto(s)
Hibridación Genética , Población/genética , Aislamiento Reproductivo , Animales , Evolución Biológica , ADN Mitocondrial/genética , Flujo Génico , Especiación Genética , Genotipo , Repeticiones de Microsatélite/genética , Papio , Conducta Sexual Animal
17.
Appl Environ Microbiol ; 77(17): 6208-14, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21742922

RESUMEN

The standard test methods used to assess the efficiency of a disinfectant applied to surfaces are often based on counting the microbial survivors sampled in a liquid, but total cell removal from surfaces is seldom achieved. One might therefore wonder whether evaluations of microbial survivors in liquid-sampled cells are representative of the levels of survivors in whole populations. The present study was thus designed to determine the "damaged/undamaged" status induced by a peracetic acid disinfection for Bacillus atrophaeus spores deposited on glass coupons directly on this substrate and to compare it to the status of spores collected in liquid by a sampling procedure. The method utilized to assess the viability of both surface-associated and liquid-sampled spores included fluorescence labeling with a combination of Syto 61 and Chemchrome V6 dyes and quantifications by analyzing the images acquired by confocal laser scanning microscopy. The principal result of the study was that the viability of spores sampled in the liquid was found to be poorer than that of surface-associated spores. For example, after 2 min of peracetic acid disinfection, less than 17% ± 5% of viable cells were detected among liquid-sampled cells compared to 79% ± 5% or 47% ± 4%, respectively, when the viability was evaluated on the surface after or without the sampling procedure. Moreover, assessments of the survivors collected in the liquid phase, evaluated using the microscopic method and standard plate counts, were well correlated. Evaluations based on the determination of survivors among the liquid-sampled cells can thus overestimate the efficiency of surface disinfection procedures.


Asunto(s)
Bacillus/efectos de los fármacos , Desinfectantes/farmacología , Desinfección/métodos , Microbiología Ambiental , Viabilidad Microbiana/efectos de los fármacos , Esporas/efectos de los fármacos , Carga Bacteriana/métodos , Colorantes Fluorescentes/metabolismo , Vidrio , Ácido Peracético/farmacología , Coloración y Etiquetado/métodos
18.
Pathol Biol (Paris) ; 59(3): e63-72, 2011 Jun.
Artículo en Francés | MEDLINE | ID: mdl-20116940

RESUMEN

Thermal injury induce a two-phase inflammatory response: first, a pro-inflammatory status, resulting in a systemic inflammatory response syndrome, then an anti-inflammatory phase characterized by a profound defect in cellular-mediated immunity. This inflammatory reaction proceeds from complex phenomenons in whom many cellular elements are involved (macrophage is the central one) and very complex molecular products interact (especially cytokines). These phenomenons promote significant physiopathologic consequences, especially on cardiovascular homeostasis and endothelial permeability, that lower the prognosis. The inflammatory reaction can be modified, enhanced or maintained by adverse events (i.e. infection) resulting in degradation of clinical situation. Despite a better comprehension of the phenomenons underlying this inflammatory process, diagnosis or therapeutic applications are at that time disappointing.


Asunto(s)
Quemaduras/fisiopatología , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Biomarcadores , Quemaduras/complicaciones , Quemaduras/inmunología , Quemaduras/cirugía , Permeabilidad Capilar , Citocinas/fisiología , Desbridamiento , Radicales Libres , Hemodinámica , Hemofiltración , Humanos , Inmunidad Celular , Infecciones/complicaciones , Mediadores de Inflamación , Hierro/metabolismo , Macrófagos/fisiología , Modelos Biológicos , Pronóstico , Trasplante de Piel , Linfocitos T/inmunología , Trombofilia/etiología
19.
J Med Vasc ; 46(2): 53-65, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33752847

RESUMEN

PURPOSE: Lung cancer and atherosclerosis share common risk factors. Literature data suggest that the prevalence of lung malignancy in patients with peripheral arterial disease (PAD) is higher than in the general population. Our goal was to determine, through a systematic literature review, the prevalence of lung cancer in patients with PAD. METHODS: We consulted available publications in the Cochrane library, MEDLINE, PUBMED, EMBASE, and ClinicalTrials.gov. We included all articles, written in English or French, published between 1990 and 2020 reporting the prevalence of lung cancer in patients with PAD (atherosclerotic aortic aneurysm or peripheral occlusive diseases). Patients with coronary artery disease, cardiac valvulopathy or carotid stenosis were not included. We did not include case reports. We performed a critical analysis of each article. Data were collected from two independent readers. A fixed effect model meta-analysis allowed to estimate a summary prevalence rate. RESULTS: We identified 303 articles, and selected 19 articles according to selection criteria. A total of 16849 patients were included (mean age 68.3 years, 75.1% of males). Aortic aneurysms were found in 29% of patients and atherosclerotic occlusive disease in 66% of patients. Lung cancer was identified in 538 patients, representing a prevalence of 3%. DISCUSSION: Lung cancer is found in 3% of patients with atherosclerotic PAD. This prevalence is higher than that found in lung cancer screening programs performed in the general population of smokers and former smokers. These patients should be screened for lung cancer. Their selection may dramatically increase the benefit of lung cancer screening.


Asunto(s)
Aneurisma de la Aorta/epidemiología , Neoplasias Pulmonares/epidemiología , Enfermedad Arterial Periférica/epidemiología , Anciano , Aneurisma de la Aorta/diagnóstico por imagen , Detección Precoz del Cáncer , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico , Prevalencia , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
20.
Mol Ecol ; 19(2): 292-306, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20041992

RESUMEN

Numerous genes in diverse organisms have been shown to be under positive selection, especially genes involved in reproduction, adaptation to contrasting environments, hybrid inviability, and host-pathogen interactions. Looking for genes under positive selection in pathogens has been a priority in efforts to investigate coevolution dynamics and to develop vaccines or drugs. To elucidate the functions involved in host specialization, here we aimed at identifying candidate sequences that could have evolved under positive selection among closely related pathogens specialized on different hosts. For this goal, we sequenced c. 17,000-32,000 ESTs from each of four Microbotryum species, which are fungal pathogens responsible for anther smut disease on host plants in the Caryophyllaceae. Forty-two of the 372 predicted orthologous genes showed significant signal of positive selection, which represents a good number of candidate genes for further investigation. Sequencing 16 of these genes in 9 additional Microbotryum species confirmed that they have indeed been rapidly evolving in the pathogen species specialized on different hosts. The genes showing significant signals of positive selection were putatively involved in nutrient uptake from the host, secondary metabolite synthesis and secretion, respiration under stressful conditions and stress response, hyphal growth and differentiation, and regulation of expression by other genes. Many of these genes had transmembrane domains and may therefore also be involved in pathogen recognition by the host. Our approach thus revealed fruitful and should be feasible for many non-model organisms for which candidate genes for diversifying selection are needed.


Asunto(s)
Basidiomycota/genética , Interacciones Huésped-Patógeno/genética , Selección Genética , Caryophyllaceae/microbiología , Análisis por Conglomerados , ADN de Hongos/genética , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Genes Fúngicos , Enfermedades de las Plantas/microbiología , Alineación de Secuencia , Análisis de Secuencia de ADN , Especificidad de la Especie
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