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1.
J Invertebr Pathol ; 174: 107436, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32619548

RESUMEN

Several isolates of Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Hypocreales: Cordycipitacae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitacae) have been investigated as possible microbial control agents of key citrus pests in South Africa. Although laboratory results have been promising, field trials against foliar pests have shown limited success. These findings highlighted the need to investigate other biological attributes of these fungal isolates besides virulence in order to select candidates that may be better suited for the foliar environment. Thus, this study investigated the influence of temperature on the in vitro growth of seven indigenous local isolates and the humidity requirements necessary to promote successful infection, in comparison with two commercial isolates (B. bassiana PPRI 5339 and M. anisopliae ICIPE 69). All the fungal isolates grew across a range of temperatures (8-34 °C) and optimally between 26 and 28 °C. Similarly, fungal infection of Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) fifth instars occurred across a range of humidity levels (12%, 43%, 75%, 98%) regardless of fungal concentration, although external sporulation was restricted to treatments exposed to 98% relative humidity. It was concluded that neither temperature nor humidity, when considered alone, is likely to significantly influence the efficacy of any of the isolates in the field, given that they are active within temperature and humidity ranges experienced in South African citrus orchards.


Asunto(s)
Beauveria/fisiología , Humedad , Metarhizium/fisiología , Mariposas Nocturnas/microbiología , Control Biológico de Vectores , Temperatura , Animales , Beauveria/patogenicidad , Citrus/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/microbiología , Metarhizium/patogenicidad , Mariposas Nocturnas/crecimiento & desarrollo , Sudáfrica , Virulencia
2.
Fungal Biol ; 124(5): 304-310, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32389292

RESUMEN

Seven indigenous entomopathogenic fungal isolates were identified as promising biocontrol agents of key citrus pests including false codling moth, Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae), citrus thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae) and citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae) under laboratory conditions. Even though field trials using the two most virulent isolates (Beauveria bassiana G Ar 17 B3 and Metarhizium anisopliae FCM Ar 23 B3) against soil-dwelling life stages of T. leucotreta were positive, foliar application against citrus mealybugs and thrips, has been disappointing. Thus, the UV sensitivity of the seven initial promising isolates (four B. bassiana and three M. anisopliae) in comparison with two commercial isolates (M. anisopliae ICIPE 69 and B. bassiana PPRI 5339) and their formulated products were investigated in this study. All isolates investigated were highly sensitive to UV radiation, and a 2 h exposure to simulated full-spectrum solar radiation at 0.3 W/m2 killed conidia of all tested isolates. Nonetheless, variability in susceptibility was found amongst isolates after exposure for 1 h. The most virulent M. anisopliae isolate, FCM Ar 23 B3, was the most susceptible to UV radiation with <3 % relative germination, 48-51 h post-exposure. Whilst isolates of the two mycoinsecticides showed similar susceptibility to UV radiation, their formulated products (vegetable oil and emulsifiable concentrate) were tolerant, when tested for 1 h. These findings indicate that a suitable UV protectant formulation of these fungi or a different application strategy will be required for success against P. citri and S. aurantii.


Asunto(s)
Beauveria , Metarhizium , Rayos Ultravioleta , Animales , Beauveria/efectos de la radiación , Agentes de Control Biológico/efectos de la radiación , Citrus/microbiología , Metarhizium/efectos de la radiación
3.
Sci Total Environ ; 579: 1399-1409, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27913017

RESUMEN

Growing evidence suggests that anthropogenic litter, particularly plastic, represents a highly pervasive and persistent threat to global marine ecosystems. Multinational research is progressing to characterise its sources, distribution and abundance so that interventions aimed at reducing future inputs and clearing extant litter can be developed. Citizen science projects, whereby members of the public gather information, offer a low-cost method of collecting large volumes of data with considerable temporal and spatial coverage. Furthermore, such projects raise awareness of environmental issues and can lead to positive changes in behaviours and attitudes. We present data collected over a decade (2005-2014 inclusive) by Marine Conservation Society (MCS) volunteers during beach litter surveys carried along the British coastline, with the aim of increasing knowledge on the composition, spatial distribution and temporal trends of coastal debris. Unlike many citizen science projects, the MCS beach litter survey programme gathers information on the number of volunteers, duration of surveys and distances covered. This comprehensive information provides an opportunity to standardise data for variation in sampling effort among surveys, enhancing the value of outputs and robustness of findings. We found that plastic is the main constituent of anthropogenic litter on British beaches and the majority of traceable items originate from land-based sources, such as public littering. We identify the coast of the Western English Channel and Celtic Sea as experiencing the highest relative litter levels. Increasing trends over the 10-year time period were detected for a number of individual item categories, yet no statistically significant change in total (effort-corrected) litter was detected. We discuss the limitations of the dataset and make recommendations for future work. The study demonstrates the value of citizen science data in providing insights that would otherwise not be possible due to logistical and financial constraints of running government-funded sampling programmes on such large scales.


Asunto(s)
Monitoreo del Ambiente/métodos , Residuos/análisis , Contaminación del Agua/estadística & datos numéricos , Playas/estadística & datos numéricos , Plásticos/análisis , Residuos/estadística & datos numéricos , Contaminantes del Agua/análisis
4.
J Pathol ; 194(1): 27-34, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11329138

RESUMEN

Immunohistochemical staining of human breast tissues, using an antibody against fibroblast growth factor receptor 3 [FGFR-3], showed differences in cellular distribution. Both malignant and non-malignant epithelial cells contained FGFR-3 immunoreactivity, but myoepithelial cells and stroma were negative. The staining pattern in malignant epithelial cells was predominantly nuclear, whereas epithelial cells in normal breast tissue showed both cytoplasmic and nuclear elements. Reverse transcription-polymerase chain reaction (RT-PCR) revealed two isoforms of FGFR-3 corresponding to the FGFR-3-IIIb variant and a previously described exon-deleted nuclear form of FGFR-3, which were present in both malignant and non-malignant epithelial cells. The higher level of nuclear staining and loss of cytoplasmic staining seen in malignant epithelial cells did not correspond to an increase in expression of the exon-deleted form of FGFR-3, nor to any detectable activating point mutations. Since receptor activation can result in its movement to a perinuclear localization, an alternative explanation for the redistribution of FGFR-3-IIIb could be different degrees of activation by a ligand (FGF1 or FGF9). No FGF9 was detected by immunohistochemistry in breast tissues. FGF1, however, is present in the majority of breast cancers and a different tissue distribution of FGF1 was found in breast tissues, showing predominantly nuclear, or a mix of nuclear and cytoplasmic FGFR-3. The difference in FGFR-3 staining patterns may implicate this ligand-receptor pair in breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Quinasas , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Núcleo Celular/metabolismo , Femenino , Factor 1 de Crecimiento de Fibroblastos , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Isoformas de Proteínas/metabolismo , ARN Mensajero/genética , ARN Neoplásico/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
5.
Biophys J ; 78(1): 451-7, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10620308

RESUMEN

We report a novel scanning ion conductance microscopy (SICM) technique for assessing the volume of living cells, which allows quantitative, high-resolution characterization of dynamic changes in cell volume while retaining the cell functionality. The technique can measure a wide range of volumes from 10(-19) to 10(-9) liter. The cell volume, as well as the volume of small cellular structures such as lamelopodia, dendrites, processes, or microvilli, can be measured with the 2.5 x 10(-20) liter resolution. The sample does not require any preliminary preparation before cell volume measurement. Both cell volume and surface characteristics can be simultaneously and continuously assessed during relatively long experiments. The SICM method can also be used for rapid estimation of the changes in cell volume. These are important when monitoring the cell responses to different physiological stimuli.


Asunto(s)
Membrana Celular/ultraestructura , Tamaño de la Célula , Microscopía Electrónica de Rastreo/métodos , Animales , Línea Celular , Túbulos Renales/citología , Túbulos Renales/ultraestructura , Microscopía Confocal/métodos , Xenopus laevis
6.
Genomics ; 62(2): 129-38, 1999 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-10610704

RESUMEN

Imprinted genes are distinguished by different patterns of methylation on their parental alleles, a property by which imprinted loci could be identified systematically. Here, representational difference analysis (RDA) is used to clone HpaII fragments with methylation differences on the maternal and paternal copies of distal chromosome (Chr) 2 in the mouse. Uniparental inheritance for this region causes imprinting phenotypes whose molecular basis is only partially understood. RDA led to the recovery of multiple differentially methylated HpaII fragments at two major sites of imprinted methylation: paternal-specific methylation at the Nesp locus and maternal-specific methylation at the Gnasxl locus. Nesp and Gnasxl represent oppositely imprinted promoters of the Gnas gene, which encodes the G-protein subunit, Gsalpha. The organization of the Nesp-Gnasxl-Gnas region was determined: Nesp and Gnasxl were found to be 15 kb apart, and Gnasxl was found to be 30 kb upstream of Gnas. Sites of imprinted methylation were also detected at the loci for neuronatin on Chr 2 and for M-cadherin on Chr 8. RDA was highly effective at identifying imprinted methylation, and its potential applications to imprinting studies are discussed.


Asunto(s)
Mapeo Cromosómico/métodos , Metilación de ADN , Impresión Genómica , Animales , Cromograninas , Clonación Molecular , Islas de CpG/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Marcadores Genéticos , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Análisis de Secuencia de ADN/métodos
7.
Br J Cancer ; 71(2): 388-92, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7841058

RESUMEN

Open or uncontrolled studies have suggested that providing cancer patients with audiotapes of their clinical interviews can improve information recall and reduce psychological distress. We tested these hypotheses in a 'clinician-blind', prospective, randomised controlled trial. A total of 117 patients newly referred to a medical oncology clinic who were to be given 'bad news' had their consultations audiotaped. Blind to the clinician, patients were randomly allocated to receive a copy of the tape to play at home or not (control group). At 6 months follow-up, tape group patients reported positive attitudes to the audiotape and were shown to recall significantly more information about their illness than did controls. Overall improvement in psychological distress at 1 and 6 months follow-up, as measured with the 30-item General Health Questionnaire and the Hospital Anxiety and Depression Scale was no different in the two groups. However, a second-order interaction suggested that poor-prognosis patients were disadvantaged specifically by access to the audiotape, with less improvement in psychological distress at 6 months follow-up than non-tape controls. Patient access to audiotapes of clinical interviews promotes factual retention but does not reliably reduce psychological distress and may be actively unhelpful in some subgroups of patients.


Asunto(s)
Ansiedad/prevención & control , Actitud Frente a la Salud , Depresión/prevención & control , Neoplasias/psicología , Visita a Consultorio Médico , Aceptación de la Atención de Salud , Educación del Paciente como Asunto/métodos , Pacientes/psicología , Estrés Psicológico/etiología , Grabación en Cinta , Revelación de la Verdad , Adulto , Anciano , Actitud del Personal de Salud , Mecanismos de Defensa , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Pronóstico , Estudios Prospectivos , Retención en Psicología , Método Simple Ciego , Encuestas y Cuestionarios
8.
Soc Sci Med ; 32(6): 627-32, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2035038

RESUMEN

Interviews were conducted with 77 patients aged 19-84, admitted to a medical oncology ward for assessment and modification of treatment. Satisfaction with information provided about tests, symptoms and treatment was assessed, together with satisfaction with care in general, factual knowledge concerning cancer and other medical conditions, and anxiety. Habitual style of coping with stress by information-seeking vs avoidance was measured using the Miller Behavioral Style Scale. Satisfaction levels were generally high. Patients reporting the highest level of satisfaction with information were more avoidant in their coping style than the remainder, and were also less anxious. Factual knowledge about cancer was in contrast greater among patients who were less satisfied with communication. These patterns were not dependent on age or education. It is argued that satisfaction with communication in medical settings is not a simple function of communication skills and the provision of adequately structured information, but that patients' tendencies to cope with stress by seeking out or avoiding information need to be taken into account.


Asunto(s)
Adaptación Psicológica , Comunicación , Comportamiento del Consumidor/estadística & datos numéricos , Neoplasias/psicología , Educación del Paciente como Asunto/normas , Adulto , Anciano , Anciano de 80 o más Años , Escolaridad , Femenino , Conocimientos, Actitudes y Práctica en Salud , Relaciones Paciente-Hospital , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias/terapia , Factores Socioeconómicos
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