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1.
Glob Chang Biol ; 30(3): e17187, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38456203

RESUMEN

Body size is a key component of individual fitness and an important factor in the structure and functioning of populations and ecosystems. Disentangling the effects of environmental change, harvest and intra- and inter-specific trophic effects on body size remains challenging for populations in the wild. Herring in the Northwest Atlantic provide a strong basis for evaluating hypotheses related to these drivers given that they have experienced significant warming and harvest over the past century, while also having been exposed to a wide range of other selective constraints across their range. Using data on mean length-at-age 4 for the sixteen principal populations over a period of 53 cohorts (1962-2014), we fitted a series of empirical models for temporal and between-population variation in the response to changes in sea surface temperature. We find evidence for a unified cross-population response in the form of a parabolic function according to which populations in naturally warmer environments have responded more negatively to increasing temperature compared with those in colder locations. Temporal variation in residuals from this function was highly coherent among populations, further suggesting a common response to a large-scale environmental driver. The synchrony observed in this study system, despite strong differences in harvest and ecological histories among populations and over time, clearly indicates a dominant role of environmental change on size-at-age in wild populations, in contrast to commonly reported effects of fishing. This finding has important implications for the management of fisheries as it indicates that a key trait associated with population productivity may be under considerably less short-term management control than currently assumed. Our study, overall, illustrates the need for a comparative approach within species for inferences concerning the many possible effects on body size of natural and anthropogenic drivers in the wild.


Asunto(s)
Ecosistema , Peces , Animales , Explotaciones Pesqueras , Temperatura , Tamaño Corporal
2.
Ecol Appl ; 29(6): e01921, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31059188

RESUMEN

Benefitting from reduced harvesting and an end to culling, many marine mammals are now recovering from past overexploitation. These recoveries represent important conservation successes but present a serious conservation problem when the recovering mammals are predators of species of conservation concern. Here, we examine the role of predation by recovering grey seals (Halichoerus grypus) in the near-extinction of a unique skate population in the southern Gulf of St. Lawrence (sGSL) in Atlantic Canada. Winter skate (Leucoraja ocellata) in the sGSL are distinct from winter skate elsewhere and may represent an endemic species. Their adult abundance has declined by 98% since 1980, and these skates are now detectable in only a small fraction of their former range. Population modeling indicates that the ongoing collapse of this population is due to increases in the natural mortality of adults. Based on model projections, this population would be extinct by mid-century if its current rate of productivity were to persist. A second population model incorporated predation by grey seals. Model estimates of skate consumption by seals were consistent with historical and recent estimates of the contribution of skates to grey seal diets. The estimated consumption accounted for the increases in the natural mortality of adult skates. A Type III functional response for grey seals preying on winter skate emerged from the model results. This indicates that, when skate abundance is very low, grey seals are expected to switch to alternate prey, resulting in declines in the mortality of skates due to predation. Consequently, contrary to projections at current productivity, winter skate are expected to be trapped at very low abundance in a "predator pit" instead of declining to extinction. Nonetheless, extinction risk would remain very high at the very small population size in the predator pit. Our results emphasize the need for an ecosystem-based approach to the management of living resources in this ecosystem.


Asunto(s)
Phocidae , Rajidae , Animales , Canadá , Ecosistema , Conducta Predatoria
3.
J Fish Biol ; 94(1): 40-52, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30357836

RESUMEN

The diet of repeat-spawner Atlantic salmon Salmo salar was investigated using carbon and nitrogen stable-isotope values from the outer growth band of scales, which reflect the fish's consumption and growth during their most recent marine phase. Isotope values for S. salar displaying different spawning strategies were compared between and within the Miramichi and Nashwaak Rivers, New Brunswick, Canada and a Bayesian mixing model was used to infer dietary contributions from potential prey items. Significant differences in the stable-isotope values were found among spawning strategies and between rivers, indicating differences in diet and feeding area, consistent with hypotheses. Bayesian mixing model results inferred the main prey items consumed during marine feeding by S. salar to consist of hyperiid amphipods and capelin Mallotus villosus for repeat alternate spawners from both rivers, sandlance Ammodytes sp. for repeat consecutive spawners from the Miramichi River and amphipods for repeat consecutive spawners from the Nashwaak River. These results demonstrate the diversity of feeding tactics among S. salar spawning strategies from the same river and between populations from different rivers. Accounting for differences in prey availability and the subsequent impact on S. salar diet and spawner return rates (i.e., marine survival) will facilitate the application of ecosystem-based management practices, such as ensuring that fisheries for forage species do not indirectly adversely affect S. salar return rates.


Asunto(s)
Dieta , Salmo salar/fisiología , Conducta Sexual Animal , Animales , Teorema de Bayes , Isótopos de Carbono/análisis , Ecosistema , Nuevo Brunswick , Isótopos de Nitrógeno/análisis , Osmeriformes , Ríos
4.
J Environ Manage ; 204(Pt 1): 404-412, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28915475

RESUMEN

Species that have a high likelihood of surviving the discarding process have become great concern since the European Union reformed the Common Fisheries Policy and enacted a landing obligation prohibiting the discarding any individuals of species under quota. Among species presenting an elevated survival potential, plaice (Pleuronectes platessa) is one of the most discarded in the coastal otter trawl fishery in the English Channel. The objective of this study is to provide the most reliable estimates of plaice survival after release in commercial conditions, and to identify the factors that influence survival rates. A captivity experiment was conducted in January-February in the English fishery to assess the survival of discarded plaice as a function of a semi-quantitative index of fish vitality, which has been demonstrated to be a good proxy of fish survival in comparable fishing and environmental conditions. This study examined the potential of this index to estimate discard survival in three trials from the English and French fisheries and at three different seasons. The vitality index was then used to analyse the influence of several factors (fishing practices, environmental conditions and fish biological characteristics) on the discard survival. The survival rates for plaice were accurately estimated at 62.8% in January-February, 66.6% in November and 45.2% in July. While these rates remained substantial whatever the fishing, environmental or fish biological conditions, the time fish spent on the deck, the bottom and air temperatures, the tow depth and the fish length had a significant influence on plaice survival. In practice, plaice survival could be enhanced by releasing the fish early during catch sorting and avoiding exposure to extreme air temperatures.


Asunto(s)
Lenguado , Nutrias/metabolismo , Animales , Ambiente , Explotaciones Pesqueras
5.
Regul Toxicol Pharmacol ; 81: 334-340, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27670079

RESUMEN

The European Commission has established a Nanomaterials Repository that hosts industrially manufactured nanomaterials that are distributed world-wide for safety testing of nanomaterials. In a first instance these materials were tested in the OECD Testing Programme. They have then also been tested in several EU funded research projects. The JRC Repository of Nanomaterials has thus developed into serving the global scientific community active in the nanoEHS (regulatory) research. The unique Repository facility is a state-of-the-art installation that allows customised sub-sampling under the safest possible conditions, with traceable final sample vials distributed world-wide for research purposes. This paper describes the design of the Repository to perform a semi-automated subsampling procedure, offering high degree of flexibility and precision in the preparation of NM vials for customers, while guaranteeing the safety of the operators, and environmental protection. The JRC nanomaterials are representative for part of the world NMs market. Their wide use world-wide facilitates the generation of comparable and reliable experimental results and datasets in (regulatory) research by the scientific community, ultimately supporting the further development of the OECD regulatory test guidelines.


Asunto(s)
Ensayo de Materiales , Nanoestructuras/química , Nanotecnología/métodos , Investigación , Automatización , Humanos
6.
J Anim Ecol ; 84(5): 1286-98, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25976520

RESUMEN

1. Numerous studies have shown that, at spatial scales of metres to several kilometres, animals balance the trade-off between foraging success and predation mortality by increasing their use of safer but less profitable habitats as predation risk increases. However, it is less clear whether prey respond similarly at the larger spatiotemporal scales of many ecosystems. 2. We determine whether this behaviour is evident in a large marine ecosystem, the southern Gulf of St. Lawrence (sGSL, 75 000 km(2) ) over a 42-year period. This ecosystem is characterized by a recent increase in the abundance of a large marine predator, the grey seal (Halichoerus grypus Fabricius), by more than an order of magnitude. 3. We compared changes in spatial distribution over the 1971-2012 period between important prey of grey seals (Atlantic cod, Gadus morhua L.; white hake, Urophycis tenuis Mitchill; and thorny skate, Amblyraja radiata Donovan) and non-prey fishes. 4. Distribution was modelled using generalized additive models incorporating spatially variable effects of predation risk, density dependence and water temperature. Distributions of cod, hake and skate were strongly related to risk of predation by seals, with distribution shifting into lower risk areas as predation risk increased. Non-prey species did not show similar changes in habitat use. Spatial variation in fish condition suggests that these low-risk areas are also less profitable for cod and skate in terms of food availability. The effects of density dependence and water temperature were also important in models, but did not account for the changes in habitat use as the risk of predation increased. 5. These results indicate that these fish are able to assess and respond to spatial variation in predation risk at very large spatial scales. They also suggest that non-consumptive 'risk' effects may be an important component of the declines in productivity of seal prey in this ecosystem, and of the indirect effects at lower trophic levels.


Asunto(s)
Distribución Animal , Gadiformes/fisiología , Conducta Predatoria , Phocidae/fisiología , Rajidae/fisiología , Animales , Canadá , Cadena Alimentaria , Gadus morhua/fisiología
7.
Eur J Dent Educ ; 17(3): 143-53, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23815691

RESUMEN

BACKGROUND: This study aims to evaluate whether an e-learning curriculum was sufficient to impart the necessary knowledge to dentists to allow them to implement an oral health promotion intervention in an institution for persons with disability. MATERIALS AND METHODS: Participants were asked to complete a 10-module online training course and to implement a standardised intervention in an institution. The outcome measures were as follows: online tracking of progress; multiple choice questionnaires completed at the end of most modules; self-efficacy questionnaire completed before and after online training; completion of training and calibration in the use of a standardised risk assessment form; initiation and full completion of an oral health promotion intervention in an institution; satisfaction of participants with the online training experience; and evaluation of the impact of the intervention by the institution staff. RESULTS: The study sample included 26 dentists. The 10 modules were passed by 24 dentists, and the mean value of the highest overall score recorded in the multiple questionnaires was 88.4% (± 4.0). Twenty participants completed the self-efficacy questionnaire before and after training; the mean values of scores after training were statistically different and higher than those at baseline. Questionnaire regarding satisfaction with the online training experience was completed by 22 participants; all of them stated that they were satisfied with the online training experience. CONCLUSIONS: The results indicate that the online training course helped participants to increase self-efficacy and to provide interventions in institutions. This study could have implications for both undergraduate and postgraduate dental education in France.


Asunto(s)
Curriculum , Personas con Discapacidad/educación , Educación en Odontología/métodos , Educación a Distancia/métodos , Promoción de la Salud/métodos , Salud Bucal/educación , Femenino , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Estudios Prospectivos , Medición de Riesgo/métodos , Autoeficacia , Encuestas y Cuestionarios
8.
Transbound Emerg Dis ; 66(2): 882-896, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30548809

RESUMEN

In July 2014, an outbreak of severe haemorrhagic disease in a domestic pig population, was reported in San-Pedro, the second seaport city of Ivory Coast. Animals of all age groups developed clinical signs consistent with African swine fever (ASF). Tissue and serum samples from dead pigs were sent to the laboratory for diagnostic confirmation and molecular characterization based on the partial B646L (p72), the full E183L (p54) gene and the central variable region of the B602L gene. The PCR results confirmed the outbreak of ASF. Phylogenetic analyses based on p72 and p54 sequences showed that the San-Pedro 2014 outbreak virus strain belongs to p72 genotype I. The Analysis of the tetrameric amino acid repeat regions of the B602L gene showed two repeat signatures which differ by an extra A = CAST in the second signature. The ASFV sequence of the San-Pedro 2014 outbreak strain is closely related to historical and recent ASFV strains collected in Angola and Cameroon whose ships have repeatedly visited the seaport of San-Pedro from March to June 2014. The 2014 viruses are distinct from the strains involved in the previous ASF wave in 1996 in Ivory Coast.


Asunto(s)
Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/virología , Brotes de Enfermedades/veterinaria , Enfermedades de los Porcinos/virología , Fiebre Porcina Africana/epidemiología , Animales , Proteínas de la Cápside/genética , Côte d'Ivoire/epidemiología , Genoma Viral/genética , Genotipo , Técnicas de Genotipaje/veterinaria , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN , Porcinos , Enfermedades de los Porcinos/epidemiología , Proteínas Virales/genética
9.
NanoImpact ; 12: 18-28, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30505982

RESUMEN

Legislation addressing environmental, health and safety aspects of nanomaterials in consumer products and ensuring their safe use is being continuously updated in the European Union and globally. This leads to a growing need for tools to implement this developing legislation. A freely accessible inventory of ready-to-use and publicly available tools that together cover the tasks within a nanomaterial safety assessment process was built in the presented work. This inventory is a unique metadata set in Excel® format: the 'NANoREG Toolbox', which assembles information needed for selecting and accessing instruments that meet specific goals. The recorded tools are categorised according to their purpose, type and regulatory status. The Toolbox covers an unprecedented and broad range of over 500 current tools, developed in Europe and beyond. While NANoREG focussed on safety assessment under the EU Regulation on Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), the instruments in the Toolbox are relevant and useful for nanomaterial safety assessments worldwide.

10.
PLoS One ; 13(5): e0195433, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29851955

RESUMEN

The effects of two different slipping methods on the survival, physical and physiological response of sardines, Sardina pilchardus, captured in a purse-seine fishery were investigated in southern Portugal. Sardines were collected and transferred into holding tanks onboard a commercial fishing vessel after being captured, crowded and deliberately released using two slipping procedures: standard and modified. The standard slipping procedure aggregated fish at high densities and made them "roll over" the floatline, while the modified procedure aggregated the fish at moderate densities and enabled them to escape through an opening created by adding weights to the floatline. Both slipping methods were compared with minimally harmed non-slipped sardines (sardines collected from the loose pocket of the purse seine). Survival rates were monitored in captivity over 28 days using three replicates for each treatment. The estimated survival of sardines was 43.6% for the non-slipped fish, 44.7% for the modified slipping and 11.7% for the standard slipping treatments. Scale loss indicated the level of physical impact experienced, with dead fish from the non-slipped and modified slipping technique showing significantly lower scale loss than those fish from the standard slipping treatment within the same period. Of the physiological indicators of stress measured, cortisol, glucose, lactate and osmolality attained peak values during slipping and up to the first hours after introduction to captivity. This work indicates that although delayed mortality after release may be substantial, appropriately modified slipping techniques significantly enhance survival of slipped sardines.


Asunto(s)
Aglomeración , Explotaciones Pesqueras , Peces/fisiología , Estrés Fisiológico , Animales , Portugal , Alimentos Marinos
11.
Br Dent J ; 220(4): 197-203, 2016 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-26917309

RESUMEN

The French oral health system is based on the provision of dental treatment and is organised around a fee-per-item model. The system is funded by a complex mix of public and complementary health insurance schemes. The system is successful in that it provides access to affordable dental treatment to the majority of the French population. However, France had the highest health expenditure as a share of gross domestic product (GDP) of all European Union countries in 2008 and rising oral health inequalities may be exacerbated by the manner in which oral health care is provided and funded. In addition, there is no organised national strategy for the prevention of oral diseases or for oral health promotion.


Asunto(s)
Atención a la Salud/organización & administración , Atención Odontológica/organización & administración , Atención a la Salud/economía , Atención Odontológica/economía , Educación en Odontología , Unión Europea , Francia/epidemiología , Costos de la Atención en Salud , Promoción de la Salud/organización & administración , Financiación de la Atención de la Salud , Humanos , Seguro Odontológico , Salud Bucal , Odontología Preventiva/organización & administración , Enfermedades Estomatognáticas/epidemiología
12.
Science ; 352(6284): 423, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-27102474

RESUMEN

Pershing et al (Science, 13 November 2015, p. 809) concluded that recent warming in the Gulf of Maine contributed to the collapse of Gulf of Maine cod. We argue that this conclusion is based on a flawed analysis of the population dynamics of this cod stock. We believe that understanding the potential role of climate change in the collapse of this stock requires more defensible analyses.


Asunto(s)
Adaptación Fisiológica , Explotaciones Pesqueras , Gadus morhua/fisiología , Calentamiento Global , Animales
13.
Biochim Biophys Acta ; 752(3): 383-95, 1983 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-6307384

RESUMEN

We have investigated the transformation of exogenous radioactive free fatty acids by cultured glial cells and their incorporation into complex lipids. The cells were either tumor lines (C6 and NN) or primary cultures from newborn rat hemispheres. The tumor lines could undergo morphological differentiation with dibutyryl cyclic AMP or bromodeoxyuridine. The fatty acid precursors used were palmitic, stearic, oleic, linoleic and linolenic acids. Tumor cells presented a higher incorporation of the precursors in the cell lipid acyl groups than did normal cells. Tumor cells desaturated and/or elongated palmitic, stearic and oleic acid to a higher extent than did normal cells. In contrast, tumor cells transformed linoleic and linolenic acids to their polyunsaturated derivatives to a lower extent than did normal cells. In differentiated tumor cells, these patterns of metabolism were shifted toward the patterns of normal cells. Tumor cells did not exhibit delta 4-desaturase activity, but such activity was restored in the C6 line upon dibutyryl cyclic AMP-induced differentiation. Transformation of linoleic and linolenic acid is likely to proceed through initial delta 6 desaturation. Phospholipids were preferentially labelled with the radioactive fatty acids, and only a little radioactivity was found in the neutral lipid fraction, mainly in diacylglycerols. Each fatty acid precursor label was incorporated in individual phospholipids to a proportion which reflected the typical acyl group composition of glycerophospholipids; we observed high levels of incorporation of palmitic acid and its derivatives into choline glycerophospholipids, and high levels of incorporation of linolenic acid and its derivatives into ethanolamine glycerophospholipids. This pattern was more marked in tumor cells than in normal cells, and the differentiation of tumor cells partially restored the normal pattern, mainly in bromodeoxyuridine-treated NN cells. Both types of differentiation of glial cell lines can be useful as models for the understanding of membrane physiology in normal and tumor cells.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Glioma/metabolismo , Neuroglía/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/metabolismo , Bromodesoxiuridina/farmacología , Bucladesina/farmacología , Radioisótopos de Carbono , Células Cultivadas , Cricetinae , Cinética , Neoplasias Experimentales/metabolismo , Neuroglía/efectos de los fármacos , Ratas
14.
Parasite ; 12(3): 271-5, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16218216

RESUMEN

Leishmaniosis caused by Leishmania infantum is an endemic zoonosis present in the Mediterranean area. Canidae (dog and fox) constitute the main reservoir hosts for the parasite, whilst wild rodents or the cat can be carriers of the protozoan and are considered as secondary potential reservoirs. This paper describes a case of disseminated feline leishmaniosis with cutaneous (ulcerative), visceral (spleen and lymph nodes) and blood involvement in a FIV-FelV positive cat. The microscopic identification of the Leishmania infection was initially made on a skin biopsy of the temporal area, where a squamous cell carcinoma was diagnosed. The diagnosis of the disease was achieved by several serological techniques (ELISA, IFAT and Western-blot). The strain was obtained by blood culture, characterized by electrophoresis of isoenzymes and identified as Leishmania infantum zymodeme MON-1. Since the infection due to L. infantum is a zoonosis, the potential feline reservoir should be more investigated. Serological analysis by Western blot on domestic cats provides a useful tool. In veterinary practice, feline leishmaniosis should be systematically included in the differential diagnosis when compatible cutaneous lesions are present, especially in the endemic areas of canine leishmaniosis.


Asunto(s)
Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Gatos/parasitología , Leishmania infantum , Leishmaniasis Visceral/veterinaria , Leucemia Felina/complicaciones , Animales , Carcinoma de Células Escamosas/complicaciones , Gatos , Síndrome de Inmunodeficiencia Adquirida del Felino/complicaciones , Femenino , Leishmaniasis Visceral/complicaciones , Macrófagos/parasitología , Macrófagos/patología
15.
J Fr Ophtalmol ; 27(9 Pt 1): 1039-42, 2004 Nov.
Artículo en Francés | MEDLINE | ID: mdl-15557867

RESUMEN

We report a 42-year-old woman with a hemangiopericytoma tumor located in nasal fossae, revealed by acute dacryocystitis. Clinical rhinoscopic examination and orbitofacial tomodensitometry showed tumefaction of the lacrimal sac and nasolacrimal duct. We removed the tumor by endonasal surgery. The anatomopathology examination confirmed the diagnosis of hemangiopericytoma. The internal canthus area and the maxillary sinus roof were treated with complementary irradiation.


Asunto(s)
Dacriocistitis/etiología , Hemangiopericitoma/complicaciones , Cavidad Nasal , Neoplasias Nasales/complicaciones , Enfermedad Aguda , Adulto , Femenino , Hemangiopericitoma/diagnóstico , Humanos , Neoplasias Nasales/diagnóstico
17.
Int J Biochem ; 17(5): 611-7, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2993054

RESUMEN

The incorporation and turnover of phospholipid precursors in cultured normal and tumoral glial cells was investigated during the plateau phase of growth. Glycerol was incorporated similarly by all cell types, and was renewed with a half-life of 19-37 hr. Acetate had a much longer half-life in primary cultures (50-75 hr) than in proliferative tumor cells (20-40 hr). Phosphate had a more rapid turnover rate in primary cultures (25 hr) than in proliferative tumor cells (50 hr). For all precursors, inositol- and choline phosphoglycerides had a faster turnover rate than other phospholipids.


Asunto(s)
Glioma/metabolismo , Lípidos de la Membrana/metabolismo , Neuroglía/metabolismo , Fosfolípidos/metabolismo , Acetatos/metabolismo , Animales , Bucladesina/farmacología , Células Cultivadas , Cricetinae , Glicerol/metabolismo , Semivida , Fosfatos/metabolismo , Ratas
18.
Bull Soc Ophtalmol Fr ; 90(2): 199-204, 1990 Feb.
Artículo en Francés | MEDLINE | ID: mdl-2192810

RESUMEN

The incidence of syphilitic uveitis is reportedly increasing, up to 1% uveitis in general, with often polymorphic and atypical manifestations. Three cases of syphilitic uveitis are reported here, at different stages (secondary, latent, late). The bacteriologic sterilization is often unlikely in ocular syphilis, and recurrence is frequent; therefore a high-dose intravenous penicillin G treatment is then to recommend. HIV serology must be systematically associated with syphilitic tests.


Asunto(s)
Sífilis/complicaciones , Uveítis/complicaciones , Adulto , Femenino , Humanos , Masculino , Recurrencia , Sífilis Latente/complicaciones , Factores de Tiempo , Uveítis/diagnóstico , Uveítis/fisiopatología
19.
Appl Microbiol Biotechnol ; 60(1-2): 206-11, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12382065

RESUMEN

The single-strand conformation polymorphism (SSCP) technique was used to study the evolution of a bacterial consortium during the batch oxidation of a cobaltiferous pyrite in two types of bio-reactor: a bubble column and a classical stirred tank. Sequencing 16S rDNA revealed the presence of three organisms affiliated to Leptospirillum ferrooxidans, Acidithiobacillus thiooxidans and Sulfobacillus thermosulfidooxidans, respectively. Attempts were made to determine the proportions of bacteria attached to solid particles or freely suspended in the medium using a combination of PCR-SSCP and a microscopic technique. Ac. thiooxidans-related bacteria were dominant in the liquid during the early phase of the batch, but were later supplanted by L. ferrooxidans-related bacteria. L. ferrooxidans-related organisms were always in the majority on the solids. The growth of S. thermosulfidooxidans-related bacteria seemed to be favoured by the bubble-column reactor.


Asunto(s)
Bacterias/metabolismo , ADN Ribosómico/genética , Hierro/metabolismo , Polimorfismo Conformacional Retorcido-Simple , Sulfuros/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Reactores Biológicos , ADN Bacteriano/genética , Monitoreo del Ambiente , Minería , Polimorfismo de Longitud del Fragmento de Restricción , ARN Bacteriano/genética , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética
20.
Ann. afr. méd. (En ligne) ; 5(4): 1134-1140, 2012.
Artículo en Francés | AIM | ID: biblio-1259172

RESUMEN

Objectif. Determiner la contribution potentielle des techniques immunohistochimiques au diagnostic; et dans la prise en charge therapeutique des lymphomes-B agressifs chez des patients infectes ou non par le VIH; en R D Congo; dans le but de vulgarisation de cette approche; complementaire a l'etude morphologique; et indispensable pour le sous-typage de lymphomes; en particulier; de lymphomes-B agressifs. Methodes. Etude transversale et retrospective de 101 blocs de paraffine portant le diagnostic de lymphome et analyses entre 2005 et 2010; par des techniques morphologiques et immunohistochimiques; dans six laboratoires specialises de notre pays. Resultats. Les 81 blocs retenus; etaient tous CD20 positifs et CD3 negatifs; mais le profil etait variable pour d'autres marqueurs etudies. Le lymphome de Burkitt a ete identifie sur 40 blocs; incluant 7 sujets VIH+ (17;5); les lymphomes B diffus a grandes cellules; sur 35; avec 11; chez les VIH+ (31;4).Six lymphomes de forme intermediaire; dont 3; chez des sujets VIH+ (50). Conclusion. Cette etude a permis de classifier les lymphomes-B agressifs dans notre contexte; grace a l'immunohistochimie; justifiant le recours aux anticorps anti-CD20 pour leur traitement


Asunto(s)
Inmunohistoquímica , Linfoma de Células B/diagnóstico , Linfoma de Células B/terapia
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