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1.
J Helminthol ; 94: e66, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31331402

RESUMEN

The trematodes from South American reptiles are poorly known, with only one life cycle completely characterized. We used molecular and morphological methods to characterize diplostomoid metacercariae found in 29 of 86 pointedbelly frogs, Leptodactylus podicipinus (Cope, 1862) collected in a marsh pond in Selvíria, in the central-west region of Brazil. The metacercariae were identified as Heterodiplostomum lanceolatum Dubois, 1936 (Proterodiplostomidae), a rarely reported species that matures in snakes. In phylogenetic analysis of partial sequences from 28S rDNA, H. lanceolatum fell within a polytomy with the proterodiplostomid Crocodilicola pseudostoma (molecular divergence of 4.1%) and other members of the superfamily Diplostomoidea. Our collections provide insights into the ecology of this parasite, in that infected frogs were smaller than uninfected frogs, and metacercariae were more numerous in the abdominal cavity and hindlimb muscles than in abdominal muscles, which suggests directions for future research on the transmission and pathology of this proterodiplostomid.


Asunto(s)
Anuros/parasitología , Metacercarias/anatomía & histología , Trematodos/clasificación , Animales , Brasil , ADN Ribosómico/genética , Estadios del Ciclo de Vida , Metacercarias/aislamiento & purificación , Filogenia , ARN Ribosómico 28S/genética , Especificidad de la Especie , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación
2.
J Viral Hepat ; 25 Suppl 1: 6-17, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29508946

RESUMEN

Hepatitis C virus (HCV) infection is a major public health problem in the European Union (EU). An estimated 5.6 million Europeans are chronically infected with a wide range of variation in prevalence across European Union countries. Although HCV continues to spread as a largely "silent pandemic," its elimination is made possible through the availability of the new antiviral drugs and the implementation of prevention practices. On 17 February 2016, the Hepatitis B & C Public Policy Association held the first EU HCV Policy Summit in Brussels. This summit was an historic event as it was the first high-level conference focusing on the elimination of HCV at the European Union level. The meeting brought together the main stakeholders in the field of HCV: clinicians, patient advocacy groups, representatives of key institutions and regional bodies from across European Union; it served as a platform for one of the most significant disease elimination campaigns in Europe and culminated in the presentation of the HCV Elimination Manifesto, calling for the elimination of HCV in Europe by 2030. The launch of the Elimination Manifesto provides a starting point for action in order to make HCV and its elimination in Europe an explicit public health priority, to ensure that patients, civil society groups and other relevant stakeholders will be directly involved in developing and implementing HCV elimination strategies, to pay particular attention to the links between hepatitis C and social marginalization and to introduce a European Hepatitis Awareness Week.


Asunto(s)
Antivirales/uso terapéutico , Erradicación de la Enfermedad/organización & administración , Hepacivirus/fisiología , Hepatitis C/prevención & control , Erradicación de la Enfermedad/economía , Monitoreo Epidemiológico , Europa (Continente)/epidemiología , Unión Europea , Hepatitis C/epidemiología , Hepatitis C/virología , Humanos , Prevalencia
3.
J Hum Nutr Diet ; 30(2): 185-192, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27600326

RESUMEN

BACKGROUND: Waist-to-height ratio (WHtR) has been reported as a preferable risk related body fat (BF) marker, although no standardised waist circumference measurement protocol (WCmp) has been proposed. The present study aimed to investigate whether the use of a different WCmp affects the strength of relationship between WHtR and both whole and central BF in non-alcoholic fatty liver disease (NAFLD) patients. METHODS: BF was assessed with dual energy X-ray absorptiometry (DXA) in 28 NAFLD patients [19 males, mean (SD) 51 (13) years and nine females, 47 (13) years]. All subjects also underwent anthropometric evaluation including height and waist circumference (WC) measurement using four different WCmp (WC1, minimal waist; WC2, iliac crest; WC3, mid-distance between iliac crest and lowest rib; WC4, at the umbilicus) and WHtR was calculated using each WC measurements (WHtR1, WHtR2, WHtR3 and WHtR4, respectively). Partial correlations were conducted to assess the relation of WHtR and DXA assessed BF. RESULTS: All WHtR were particularly correlated with central BF, including abdominal BF (r = 0.80, r = 0.84, r = 0.84 and r = 0.78, respectively, for WHtR1, WHtR2, WHtR3 and WHtR4) and central abdominal BF (r = 0.72, r = 0.77, r = 0.76 and r = 0.71, respectively, for WHtR1, WHtR2, WHtR3 and WHtR4), after controlling for age, sex and body mass index. There were no differences between the correlation coefficients obtained between all studied WHtR and each whole and central BF variable. CONCLUSIONS: Waist-to-height ratio was found a suitable BF marker in the present sample of NAFLD patients and the strength of the relationship between WHtR and both whole and central BF was not altered by using different WCmp in the present sample of NAFLD patients.


Asunto(s)
Adiposidad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Circunferencia de la Cintura , Relación Cintura-Estatura , Absorciometría de Fotón , Adulto , Anciano , Antropometría , Composición Corporal , Estatura , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Resistencia a la Insulina , Masculino , Persona de Mediana Edad , Factores de Riesgo
4.
J Helminthol ; 90(3): 372-6, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25781630

RESUMEN

The importance of platynosomiasis has increased in feline veterinary practice, but aspects related to the specificity of Platynosomum spp. in definitive hosts requires further study. Although morphological traits suggest that the same species, P. illiciens, may infect both birds and mammals, the synonymies previously proposed have not been widely accepted, likely because host specificity is assumed. In addition, the name P. fastosum has frequently been used for parasites recovered from mammals. In the present study, metacercariae (n= 100/animal) of P. illiciens recovered from lizards (Hemidactylus mabouia) in Brazil were fed to Australian parakeets (Melopsittacus undulatus) and mice. Two parasites were recovered from the liver of one M. undulatus specimen during a necropsy that was performed 105 days after infection, and all mice were found to be infected with 37 ± 12 (18-48) parasites. The morphology of the P. illiciens obtained from the parakeet was similar to that of parasites obtained from mice and those described previously from naturally infected birds and mammals. Non-specificity of P. illiciens in hosts is discussed briefly, based on the parasitological and morphological results obtained during the avian experimental platynosomiasis and the epidemiology and geographical distribution of this parasite.


Asunto(s)
Dicrocoeliidae/crecimiento & desarrollo , Especificidad del Huésped , Infecciones por Trematodos/veterinaria , Animales , Aves , Brasil , Dicrocoeliidae/aislamiento & purificación , Lagartos , Mamíferos , Ratones , Infecciones por Trematodos/parasitología
5.
Allergol Immunopathol (Madr) ; 43(4): 332-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25088675

RESUMEN

BACKGROUND: Storage mites of the genus Acarus can be responsible for allergic sensitisation in domestic environments. Acarus gracilis is a frequent species in some geographical regions of the Iberian Peninsula. Since the allergenicity of this mite has not been described before, the objectives of this study were to characterise it immunologically, and to compare it with the closely related and more extensively studied species Acarus siro. METHODS: Extracts from A. gracilis and A. siro cultures were characterised by Lowry, 1D and 2D-SDS and IEF. Zymogram, and determination of different enzymatic activities were performed. Skin prick solution of A. gracilis was tested in consecutive patients attending the Hospital of Mérida (Extremadura, Spain). Serum samples from eight individuals with positive skin prick test were collected. IgE determination, immunoblot and immunoblot-inhibition studies were performed. RESULTS: Extracts of both species showed a very similar protein and allergenic profile. Allergens at 14 and 17 kDa were clearly recognised in both extracts by serum samples. Immunoblot-inhibition studies demonstrated that both extracts were totally inhibited by the opposite one. Enzymatic activity was similar in both cases with the most important differences being in kallikrein, serine protease and collagenase activities. CONCLUSION: The storage mite A. gracilis has a similar protein and allergen profile to A. siro and can induce allergic sensitisation. Due to the higher prevalence of this species respect to A. siro in some regions, more studies are needed to determine the clinical significance of sensitisation to this storage mite species.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad/inmunología , Hipersensibilidad/microbiología , Ácaros/inmunología , Animales , Western Blotting , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Humanos , Hipersensibilidad/epidemiología , Inmunoglobulina E/sangre , Prevalencia , Pruebas Cutáneas
6.
Bioact Mater ; 38: 499-511, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38798890

RESUMEN

The timely establishment of functional neo-vasculature is pivotal for successful tissue development and regeneration, remaining a central challenge in tissue engineering. In this study, we present a novel (micro)vascularization strategy that explores the use of specialized "vascular units" (VUs) as building blocks to initiate blood vessel formation and create perfusable, stroma-embedded 3D microvascular networks from the bottom-up. We demonstrate that VUs composed of endothelial progenitor cells and organ-specific fibroblasts exhibit high angiogenic potential when embedded in fibrin hydrogels. This leads to the formation of VUs-derived capillaries, which fuse with adjacent capillaries to form stable microvascular beds within a supportive, extracellular matrix-rich fibroblastic microenvironment. Using a custom-designed biomimetic fibrin-based vessel-on-chip (VoC), we show that VUs-derived capillaries can inosculate with endothelialized microfluidic channels in the VoC and become perfused. Moreover, VUs can establish capillary bridges between channels, extending the microvascular network throughout the entire device. When VUs and intestinal organoids (IOs) are combined within the VoC, the VUs-derived capillaries and the intestinal fibroblasts progressively reach and envelop the IOs. This promotes the formation of a supportive vascularized stroma around multiple IOs in a single device. These findings underscore the remarkable potential of VUs as building blocks for engineering microvascular networks, with versatile applications spanning from regenerative medicine to advanced in vitro models.

7.
Tissue Antigens ; 82(6): 374-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24498993

RESUMEN

Human leukocyte antigen (HLA)-B27 is the mostly known major histocompatibility complex (MHC) gene associated with ankylosing spondylitis (AS). Nonetheless, there is substantial evidence that other MHC genes appear to be associated with the disease, although it has not yet been established whether these associations are driven by direct associations or by linkage disequilibrium (LD) mechanisms. We aimed to investigate the contributions of HLA class I and II alleles and B27-haplotypes for AS in a case-control study. A total of 188 HLA-B27 AS cases and 189 HLA-B27 healthy controls were selected and typed for HLA class I and II by the Luminex polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) method. Allelic and haplotypic distributions were estimated by maximum likelihood method using Arlequin v3.11 and statistical analysis were performed by Stata10.1. No associations were found between non-HLA-B27 loci and AS susceptibility, but several associations were observed for phenotypic features of the disease. DRB1*08 was identified as a risk factor for uveitis and DQB1*04 seems to provide protection for AS severity (functional, metrological and radiological indexes). A*02/B27/C*02/DRB1*01/DQB1*05 [P<0.0001; odds ratio (OR) = 39.06; 95% confidence interval (CI) (2.34-651)] is the only haplotype that seems to confer susceptibility to AS. Moreover, the haplotype A*02/B27/C*01/DRB1*08/DQB1*04 seems to provide protection for disease functional and radiological repercussions. Our findings are compatible with the hypothesis that other genes within the HLA region besides HLA-B27 might play some role in AS susceptibility and severity.


Asunto(s)
Predisposición Genética a la Enfermedad , Antígeno HLA-B27/genética , Espondilitis Anquilosante/genética , Espondilitis Anquilosante/inmunología , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Antígeno HLA-A2/genética , Cadenas HLA-DRB1/genética , Haplotipos , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Portugal , Adulto Joven
8.
Phys Rev Lett ; 110(16): 167402, 2013 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-23679637

RESUMEN

In this Letter, the photoinduced switching of the single nitrogen-vacancy (NV) center between two different charge states, negative (NV(-)) and neutral (NV(0)), is studied under resonant excitation at liquid helium temperature. We show that resonant conversion of NV(0) to NV(-) significantly improves spectral stability of the NV(-) defect and allows high fidelity initialization of the spin qubit. Based on density functional theory calculations a novel mechanism involving an Auger ionization of NV(-) and charge transfer of an electron from the valence band to NV(0) is discussed. This study provides further insight into the charge dynamics of the NV center, which is relevant for quantum information processing based on an NV(-) defect in diamond.

9.
Cryo Letters ; 34(1): 100-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23435706

RESUMEN

Lipocryolysis is considered as an effective, well-tolerated non-invasive procedure to reduce local adiposities. However there is little information about its mechanism of action by the procedure. It is proposed that lipid phase transition or crystallization may be an unleashed apoptotic stimulus. Yet, the post-lipocryolysis apoptosis is not easily confirmed, least of all is its correlation with crystallization. In this study adipocytes from rat fat tissue were exposed to a lipocryolysis-session-like stimulus. Lipid changes were observed in all test sample.


Asunto(s)
Adipocitos/citología , Tejido Adiposo Blanco/citología , Lípidos/análisis , Adipocitos/química , Animales , Apoptosis , Células Cultivadas , Frío/efectos adversos , Cristalización , Lipectomía , Masculino , Transición de Fase , Ratas , Ratas Wistar
10.
Cryo Letters ; 34(6): 619-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24441372

RESUMEN

Lipocryolysis always claimed localized-fat-reduction to be a consequence of local apoptotic adipocyte destruction triggered by intracellular triglyceride crystallization. The idea is now under debate, for it has been suggested that the physical changes occurring in adipocytes after lipocryolysis could be better explained by a lipid gel-like transition process rather than by lipid crystallization. Since a) lipocryolysis claims apoptosis to be the key to adipocyte destruction and clinical-result achievement and b) it considers crystallization to be a necessary step for the apoptotic stimulus unleashing, any effort to untangle, prove or discard this process is very important.


Asunto(s)
Adipocitos/citología , Lípidos/química , Adipocitos/química , Animales , Apoptosis , Células Cultivadas , Frío , Cristalización , Masculino , Ratas , Ratas Wistar , Triglicéridos/química , Difracción de Rayos X
11.
Cell Death Dis ; 14(11): 781, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38016947

RESUMEN

In Alzheimer's disease (AD) more than 50% of the patients are affected by capillary cerebral amyloid-angiopathy (capCAA), which is characterized by localized hypoxia, neuro-inflammation and loss of blood-brain barrier (BBB) function. Moreover, AD patients with or without capCAA display increased vessel number, indicating a reactivation of the angiogenic program. The molecular mechanism(s) responsible for BBB dysfunction and angiogenesis in capCAA is still unclear, preventing a full understanding of disease pathophysiology. The Liver X receptor (LXR) family, consisting of LXRα and LXRß, was reported to inhibit angiogenesis and particularly LXRα was shown to secure BBB stability, suggesting a major role in vascular function. In this study, we unravel the regulatory mechanism exerted by LXRα to preserve BBB integrity in human brain endothelial cells (BECs) and investigate its role during pathological conditions. We report that LXRα ensures BECs identity via constitutive inhibition of the transcription factor SNAI2. Accordingly, deletion of brain endothelial LXRα is associated with impaired DLL4-NOTCH signalling, a critical signalling pathway involved in vessel sprouting. A similar response was observed when BECs were exposed to hypoxia, with concomitant LXRα decrease and SNAI2 increase. In support of our cell-based observations, we report a general increase in vascular SNAI2 in the occipital cortex of AD patients with and without capCAA. Importantly, SNAI2 strongly associated with vascular amyloid-beta deposition and angiopoietin-like 4, a marker for hypoxia. In hypoxic capCAA vessels, the expression of LXRα may decrease leading to an increased expression of SNAI2, and consequently BECs de-differentiation and sprouting. Our findings indicate that LXRα is essential for BECs identity, thereby securing BBB stability and preventing aberrant angiogenesis. These results uncover a novel molecular pathway essential for BBB identity and vascular homeostasis providing new insights on the vascular pathology affecting AD patients.


Asunto(s)
Enfermedad de Alzheimer , Angiopatía Amiloide Cerebral , Humanos , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Barrera Hematoencefálica/metabolismo , Angiopatía Amiloide Cerebral/complicaciones , Angiopatía Amiloide Cerebral/metabolismo , Angiopatía Amiloide Cerebral/patología , Células Endoteliales/metabolismo , Hipoxia/metabolismo , Receptores X del Hígado/genética , Receptores X del Hígado/metabolismo , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo
13.
J Nanosci Nanotechnol ; 12(11): 8589-93, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23421248

RESUMEN

We have investigated using density functional theory the effect of fluorine termination of a (001) diamond surface on the electronic energy levels of an NV- centre buried beneath the surface. We find that, like OH termination, fluorine passivates the surface and reduces the influence of the surface on the electronic properties of the NV- centre. The results have significance for the optical properties of NV- defects in nanodiamonds.


Asunto(s)
Diamante/química , Flúor/química , Modelos Químicos , Modelos Moleculares , Nanoestructuras/química , Nanoestructuras/ultraestructura , Simulación por Computador , Transporte de Electrón , Tamaño de la Partícula
14.
Allergol Immunopathol (Madr) ; 40(2): 92-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21550163

RESUMEN

BACKGROUND: Knowledge of the domestic mite fauna and allergen levels is important for a correct diagnosis and treatment of mite allergy. Our objectives were to describe the domestic mite fauna in the region of Murcia, Spain, to quantify mite allergens in dust samples obtained from mattresses of this area and to assess the influence of geographical, climatic and dwelling factors. METHODS: Dust samples were collected in a transversal descriptive study from mattresses of 51 patients who went to the Allergology Service, and from mattress of 81 neighbours or family members of these patients. A questionnaire about home environment was filled in and obtained by all participants. Mite identification was done by light microscopy and allergen determinations (Der p 1 and Der f 1) by monoclonal antibodies. RESULTS: Sixteen mite species were identified in the 132 dust samples collected. The most frequent species were Dermatophagoides farinae (36% of the samples), Dermatophagoides pteronyssinus (32%) and Tyrophagus putrescentiae (5.3%). There were significant differences among climatic regions. The coastal sector had greater mite abundance, being D. pteronyssinus more frequent and abundant than D. farinae. In inland areas D. farinae was the predominant mite species. Allergen levels correlated with the concentration of Dermatophagoides, with higher levels detected in coastal regions. Average annual temperature was the main outdoor factor that correlated with higher mite concentrations. Indoor main predictor of higher levels of mites was the presence of obvious signs of humidity in the home. CONCLUSION: This study demonstrates the existence of a mite fauna dominated by D. pteronyssinus and D. farinae with a strong influence of climatic factors and residential characteristics.


Asunto(s)
Antígenos Dermatofagoides/análisis , Proteínas de Artrópodos/análisis , Ropa de Cama y Ropa Blanca/parasitología , Cisteína Endopeptidasas/análisis , Geografía , Hipersensibilidad/epidemiología , Adolescente , Adulto , Animales , Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos/inmunología , Ropa de Cama y Ropa Blanca/estadística & datos numéricos , Clima , Cisteína Endopeptidasas/inmunología , Exposición a Riesgos Ambientales/efectos adversos , Humanos , Humedad/efectos adversos , Hipersensibilidad/inmunología , Masculino , Persona de Mediana Edad , Pyroglyphidae/inmunología , España , Adulto Joven
15.
Cryo Letters ; 33(3): 177-81, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22825784

RESUMEN

Since ancient times human beings have been conceiving methods that could help reduce the accumulation of undesired fat tissue in their own bodies. Lipocryolysis has already been recognized as an therapy for localized fat reduction by means of a combination of regulated and controlled vacuum and heat extraction therapy. This study was designed to quantify the claimed reduction of local adiposities. For this purpose, 16 treatments were analysed. The data suggested that lipocryolysis is effective for localized reduction of adiposities and that the reduction obtained are measurable.


Asunto(s)
Tejido Adiposo/cirugía , Lipectomía/métodos , Lípidos/aislamiento & purificación , Adolescente , Adulto , Anciano , Frío , Femenino , Calor , Humanos , Persona de Mediana Edad , Triglicéridos/aislamiento & purificación , Vacio , Adulto Joven
16.
Diabetologia ; 54(7): 1788-98, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21455726

RESUMEN

AIMS/HYPOTHESIS: Non-alcoholic fatty liver disease (NAFLD) is associated with insulin resistance and characterised by different degrees of hepatic lesion. Its pathogenesis and correlation with apoptosis and insulin resistance in insulin target tissues remains incompletely understood. We investigated how insulin signalling, caspase activation and apoptosis correlate with different NAFLD stages in liver, muscle and visceral adipose tissues. METHODS: Liver, muscle and adipose tissue biopsies from 26 morbidly obese patients undergoing bariatric surgery were grouped according to the Kleiner-Brunt scoring system into simple steatosis, and less severe and more severe non-alcoholic steatohepatitis (NASH). Apoptosis was assessed by DNA fragmentation, and caspase-2 and -3 activation. Insulin signalling and c-Jun NH(2)-terminal kinase (JNK) proteins were evaluated by western blot. RESULTS: Caspase-3 and -2 activation, and DNA fragmentation were markedly increased in the liver of patients with severe NASH vs in that of those with simple steatosis (p < 0.01). Muscle tissue, and to a lesser extent the liver, had decreased tyrosine phosphorylated insulin receptor and insulin receptor substrate in patients with severe NASH, compared with those with simple steatosis (p < 0.01 muscle; p < 0.05 liver). Concomitantly, Akt phosphorylation decreased in muscle, liver and visceral adipose tissues in patients with severe NASH (at least p < 0.05). Finally, JNK phosphorylation was significantly increased in muscle (p < 0.01) and liver (p < 0.05) from NASH patients, compared with tissue from those with simple steatosis. CONCLUSIONS/INTERPRETATION: Our results demonstrate a link between apoptosis, insulin resistance and different NAFLD stages, where JNK and caspase-2 may play a key regulatory role.


Asunto(s)
Apoptosis/fisiología , Hígado Graso/metabolismo , Hígado Graso/patología , Resistencia a la Insulina/fisiología , Obesidad/metabolismo , Obesidad/patología , Adulto , Femenino , Humanos , Immunoblotting , Inmunoprecipitación , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Hígado/metabolismo , Hígado/patología , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Enfermedad del Hígado Graso no Alcohólico
17.
J Hepatol ; 65(3): 643-4, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27401791
18.
Plant Dis ; 95(12): 1588, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30731981

RESUMEN

Bidens sulphurea (synonym Cosmos sulphureus) (Asteraceae), commonly known as yellow cosmos, is a native herbaceous species from Mexico that is widely used as an ornamental. It has been introduced in Brazil and has escaped from gardens, becoming a minor weed in ruderal, crop and pasture areas (2). In June 2010, groups of B. sulphurea individuals were found in a garden at the locality of Piúna, municipality of Viçosa (state of Minas Gerais, Brazil), that were severely attacked by gray mold. The disease led to flower rot with dieback of infected peduncles and stems. Plant tissues became brown to grayish brown and were covered by extensive fungal sporulation; in addition, seeds were colonized and destroyed by the fungus. A hyphomycete was regularly found associated with the diseased flowers, which was readily recognized as having a morphology typical of Botrytis cinerea: conidiophores solitary, cylindrical, terminally branched, 15 to 20 µm wide, grayish to olivaceous gray, and smooth; conidiogenous cells polyblastic, subcylindrical to ampulliform, and 120 to 230 × (13-) 14 to 16 (-19) µm; conidia ellipsoid to obovoid, 8 to 12 × 6.5 to 8 (-9) µm, with a discrete hilum at the base, 1 to 2 µm, aseptate, and hyaline. The fungus was isolated in pure culture and inoculation of one isolate on healthy B. suphurea individuals was carried out with a 2.14 × 106 conidia/ml suspension, which was sprayed to runoff onto three plants bearing four to six inflorescences. All plants were left in a moist chamber for 48 h and later transferred to a bench in a greenhouse at 21 ± 3°C. Gray mold symptoms appeared after 10 days that led to rapid and complete necrosis of flowers and peduncles. Infection first appeared on the flowers but progressed downward, leading to top dieback and finally plant death (not seen in the field). Only Botrytis cinerea was obtained in isolations from diseased flowers, demonstrating the pathogenicity of the fungus. A representative sample was deposited in the UFV herbarium (VIC 31602). The only other record of Botrytis cinerea causing gray mold of B. sulphurea is from China (1,3). To our knowledge, this is the first record of Botrytis cinerea causing gray mold on B. sulphurea in Brazil. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Botany and Mycology Laboratory, ARS, UDSA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , 2011. (2) H. Lorenzi and H. M. Souza. Plantas Ornamentais no Brasil. Plantarum, Nova Odessa, Brazil. 1995. (3) Z. Zhang. Flora Fungorum Sinicorum. Vol. 26. Botrytis, Ramularia. Science Press, Beijing, China. 2006.

19.
J Appl Genet ; 51(1): 67-72, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20145302

RESUMEN

Restocking and stock enhancement programs are now recognized as an important tool for the management of fishery resources. It is important, however, to have an adequate knowledge on the genetic population structure of both the released stock and the wild population before carrying out such programs. In this study, random amplified polymorphic DNA (RAPD) markers were applied to assess genetic diversity and population structure of wild and hatchery populations of the white seabream Diplodus sargus and the common two-banded seabream D. vulgaris (Sparidae). The estimated values for intrapopulation genetic variation, measured using the percentage of polymorphic loci (%P), Shannon index (H'), and Nei's gene diversity (h), showed high values for all populations. The percentage of genetic variation within D. sargus and D. vulgaris populations, based on coefficient of gene differentiation, reached 82.5% and 90% of the total genetic variation, respectively. An undeniable decrease in genetic variation was found in both hatchery populations, particularly in D. sargus, compared to the wild ones. However, the high values of variation within all populations and the low levels of genetic variation among populations did not indicate inbreeding or depression effects, thus indicating a fairly proper hatchery management. Nevertheless, the results of this study highlight the importance of monitoring the genetic variation of hatchery populations, particularly those to be used in restocking programs. The creation of a genetic baseline database will contribute to a more efficient conservation management and to the design of genetically sustainable restocking programs.


Asunto(s)
Variación Genética , Genética de Población , Técnica del ADN Polimorfo Amplificado Aleatorio , Dorada/crecimiento & desarrollo , Dorada/genética , Animales , Marcadores Genéticos , Geografía , Dorada/clasificación
20.
Cytogenet Genome Res ; 126(1-2): 12-20, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20016153

RESUMEN

Eukaryotic genomes contain far more DNA than needed for coding proteins. Some of these additional DNA sequences comprise non-coding repetitive DNA sequences, mostly satellite DNAs and also transposable elements usually located at the heterochromatic regions of chromosomes. Satellite DNAs consist of tandemly repeated DNA sequences inhabiting the mammalian genome, typically organized in long arrays of hundreds or thousands of copies. Different important functions have been ascribed to satellite DNA, from the imperative centromeric function in mitosis and meiosis to the recent discovery of its involvement in regulatory functions via satellite transcripts. Moreover, satellite DNAs, among other repetitive sequences, are believed to be the 'engine' triggering mammalian genome evolution. Repetitive DNAs are, most likely, the genetic factors responsible for promoting genomic plasticity and therefore higher rates of chromosome mutation. Furthermore, constitutive heterochromatin regions are thought to be 'hotspots' for structural chromosome rearrangements. A considerable collection of evidences places these sequences in the landscape of mammalian evolution. However, the mechanisms that could explain how this alliance between chromosome evolution and satellite DNA is made are still enigmatic and subject of debate. Throughout the mammalian taxa, different patterns of chromosome evolution have been widely registered from heterochromatin additions/eliminations, Robertsonian translocations, whole-arm reciprocal translocations to tandem translocations; the fact is genome's repetitive fraction is playing a central role in mammalian genome structuring. Throughout this review we will focus on the evidences that associate satellite DNAs and constitutive heterochromatin to the process of chromosome evolution and consequently to domestic species genome's remodeling.


Asunto(s)
Animales Domésticos/genética , Evolución Biológica , ADN Satélite/genética , Animales , Genoma
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