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1.
J Small Anim Pract ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961721

RESUMEN

OBJECTIVES: This retrospective cohort multicentre study aimed to characterise the signalment, clinicopathologic data, complications and the association between treatment and outcome (the reduction in ionised calcium concentration) in cats with idiopathic or chronic kidney disease-associated ionised hypercalcaemia managed with alendronate and standard treatment or standard treatment alone, and to compare the outcome between the two groups. MATERIALS AND METHODS: Medical records for cats diagnosed with idiopathic or chronic kidney disease-associated ionised hypercalcaemia were retrospectively reviewed. Cats treated with alendronate and standard treatment were assigned to the alendronate group and cats treated with standard treatment alone were assigned to the control group. The standard treatment was defined as dietary modification and/or monitoring of ionised calcium concentrations and management of complications secondary to hypercalcaemia. The follow-up period was selected as 6 months. RESULTS: Twenty-nine cats were enrolled in the study. Nine cats were included in the control group and 20 cats in the alendronate group. A significant reduction in serum ionised calcium was observed in both groups between the baseline and the follow-up visit; however, this reduction did not differ significantly between both groups (the mean change in the ionised calcium concentration in alendronate and control group was -0.18 and -0.17, respectively). Suspected bisphosphate-related osteonecrosis of the jaw was reported in one cat receiving alendronate. CLINICAL SIGNIFICANCE: In this study, similar reduction in serum ionised calcium concentration was observed in cats with ionised hypercalcaemia treated with diet alone and in cats treated with diet and alendronate. These results should be interpreted with caution, as the study was underpowered for meaningful statistical comparison. Cats receiving alendronate should be monitored for the development of adverse reactions, including osteonecrosis of the jaw.

2.
J Small Anim Pract ; 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38679786

RESUMEN

OBJECTIVES: To describe the diagnostic tests used and their comparative performance in dogs diagnosed with sinonasal aspergillosis in the United Kingdom. A secondary objective was to describe the signalment, clinical findings and common clinicopathologic abnormalities in sinonasal aspergillosis. MATERIALS AND METHODS: A multi-centre retrospective survey was performed involving 23 referral centres in the United Kingdom to identify dogs diagnosed with sinonasal aspergillosis from January 2011 to December 2021. Dogs were included if fungal plaques were seen during rhinoscopy or if ancillary testing (via histopathology, culture, cytology, serology or PCR) was positive and other differential diagnoses were excluded. RESULTS: A total of 662 cases were entered into the database across the 23 referral centres. Four hundred and seventy-five cases met the study inclusion criteria. Of these, 419 dogs had fungal plaques and compatible clinical signs. Fungal plaques were not seen in 56 dogs with turbinate destruction that had compatible clinical signs and a positive ancillary test result. Ancillary diagnostics were performed in 312 of 419 (74%) dogs with observed fungal plaques permitting calculation of sensitivity of cytology as 67%, fungal culture 59%, histopathology 47% and PCR 71%. CLINICAL SIGNIFICANCE: The sensitivities of ancillary diagnostics in this study were lower than previously reported challenging the clinical utility of such tests in sinonasal aspergillosis. Treatment and management decisions should be based on a combination of diagnostics including imaging findings, visual inspection, and ancillary testing, rather than ancillary tests alone.

3.
J Small Anim Pract ; 64(6): 401-408, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36978210

RESUMEN

OBJECTIVES: To characterise the fever episodes attributed to Shar Pei autoinflammatory disease and to identify common diagnostic and management strategies in the United Kingdom. A secondary objective was to determine risk factors associated with Shar Pei autoinflammatory disease fever episodes. METHODS: A retrospective survey was performed to characterise episodes of Shar Pei autoinflammatory disease fever and to identify commonly used treatments in affected dogs. Clinical data were collected from owners and veterinarians. Frequencies of previously proposed risk factors (skin thickness and folding, muzzle conformation) and comorbid conditions were compared between dogs that had exhibited fever episodes consistent with Shar Pei autoinflammatory disease and those who had not. RESULTS: At least one episode of fever attributed to Shar Pei autoinflammatory disease was reported in 52 of 106 (49%) Shar Pei. Nine other dogs had fever episodes consistent with Shar Pei autoinflammatory disease reported by their owners but not by veterinarians. Median rectal temperature at presentation for Shar Pei autoinflammatory disease fever was 40.1°C [104.2°F] (39.9 to 41.3°C [103.8 to 106.3°F]) and owners reported associated hyporexia (n=33, 63%) and vomiting (n=8, 15%) more frequently than veterinary records (n=22, 42% and n=0, 0%, respectively). The median number of veterinary appointments for Shar Pei autoinflammatory disease was two per dog (1 to 15) while owners reported a median of four episodes per dog per year. None of the assessed phenotypic variants or comorbidities were significantly associated with exhibiting Shar Pei autoinflammatory disease fever episodes. CLINICAL SIGNIFICANCE: Episodes of Shar Pei autoinflammatory disease fever were reported approximately twice as frequently by owners compared to veterinary records, suggesting the burden of this condition may be underestimated by veterinarians. Specific risk factors for Shar Pei autoinflammatory disease fever were not identified.


Asunto(s)
Enfermedades de los Perros , Enfermedades Autoinflamatorias Hereditarias , Animales , Perros , Estudios Retrospectivos , Factores de Riesgo , Enfermedades Autoinflamatorias Hereditarias/veterinaria , Reino Unido/epidemiología , Enfermedades de los Perros/epidemiología
4.
Ultrasound Obstet Gynecol ; 58(4): 509-518, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33847422

RESUMEN

OBJECTIVE: To determine the incremental yield of exome sequencing (ES) over chromosomal microarray analysis (CMA) or karyotyping in prenatally diagnosed non-immune hydrops fetalis (NIHF). METHODS: A prospective cohort study (comprising an extended group of the Prenatal Assessment of Genomes and Exomes (PAGE) study) was performed which included 28 cases of prenatally diagnosed NIHF undergoing trio ES following negative CMA or karyotyping. These cases were combined with data from a systematic review of the literature. MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched electronically (January 2000 to October 2020) for studies reporting on the incremental yield of ES over CMA or karyotyping in fetuses with prenatally detected NIHF. Inclusion criteria for the systematic review were: (i) at least two cases of NIHF undergoing sequencing; (ii) testing initiated based on prenatal ultrasound-based phenotype; and (iii) negative CMA or karyotyping result. The incremental diagnostic yield of ES was assessed in: (i) all cases of NIHF; (ii) isolated NIHF; (iii) NIHF associated with an additional fetal structural anomaly; and (iv) NIHF according to severity (i.e. two vs three or more cavities affected). RESULTS: In the extended PAGE study cohort, the additional diagnostic yield of ES over CMA or karyotyping was 25.0% (7/28) in all NIHF cases, 21.4% (3/14) in those with isolated NIHF and 28.6% (4/14) in those with non-isolated NIHF. In the meta-analysis, the pooled incremental yield based on 21 studies (306 cases) was 29% (95% CI, 24-34%; P < 0.00001; I2 = 0%) in all NIHF, 21% (95% CI, 13-30%; P < 0.00001; I2 = 0%) in isolated NIHF and 39% (95% CI, 30-49%; P < 0.00001; I2 = 1%) in NIHF associated with an additional fetal structural anomaly. In the latter group, congenital limb contractures were the most prevalent additional structural anomaly associated with a causative pathogenic variant, occurring in 17.3% (19/110) of cases. The incremental yield did not differ significantly according to hydrops severity. The most common genetic disorders identified were RASopathies, occurring in 30.3% (27/89) of cases with a causative pathogenic variant, most frequently due to a PTPN11 variant (44.4%; 12/27). The predominant inheritance pattern in causative pathogenic variants was autosomal dominant in monoallelic disease genes (57.3%; 51/89), with most being de novo (86.3%; 44/51). CONCLUSIONS: Use of prenatal next-generation sequencing in both isolated and non-isolated NIHF should be considered in the development of clinical pathways. Given the wide range of potential syndromic diagnoses and heterogeneity in the prenatal phenotype of NIHF, exome or whole-genome sequencing may prove to be a more appropriate testing approach than a targeted gene panel testing strategy. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/estadística & datos numéricos , Hidropesía Fetal/diagnóstico , Cariotipificación/estadística & datos numéricos , Análisis por Micromatrices/estadística & datos numéricos , Diagnóstico Prenatal/métodos , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Secuenciación del Exoma/estadística & datos numéricos
5.
BJOG ; 128(2): 431-438, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32702189

RESUMEN

OBJECTIVE: To categorise the variants of uncertain significance found with prenatal chromosomal microarray and determine the proportion of such variants that are associated with a well-known phenotype in order to establish how often they remain truly of uncertain significance. DESIGN: Retrospective cohort study. SETTING: The University of California, San Francisco. POPULATION: All patients with a variant of uncertain significance on prenatal microarray between 2014 and 2018. METHODS: Each variant was classified as a copy number variant that (a) contains Online Mendelian Inheritance in Man (OMIM)-annotated disease-causing genes ('OMIM morbid genes'); (b) confers autosomal recessive carrier status; (c) is associated with incomplete penetrance; (d) is >1 Mb in size without OMIM morbid genes; (e) demonstrates mosaicism; or (f) contains significant regions of homozygosity. For each variant of uncertain significance, we examined the existing literature to determine whether the predicted phenotype(s) was known. MAIN OUTCOME MEASURE: Prevalence and classification of variants and how much information is available regarding the likelihood of an affected phenotype. RESULTS: Of 970 prenatal microarrays, 55 (5.8%) had at least one variant of uncertain significance. The most common were copy number variants containing OMIM morbid genes (36.8%). In all, 48 (84.2%) were associated with a known phenotype; 55 (96.5%) had data available regarding the likelihood of an affected phenotype. CONCLUSIONS: The prevalence of variants of uncertain significance with prenatal microarray was 5.8%. In the large majority of cases, data were available regarding the predicted phenotype. TWEETABLE ABSTRACT: Variants of uncertain significance occur in 5.8% of prenatal microarrays. In the overwhelming majority of cases, outcome information is available.


Asunto(s)
Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Enfermedades Fetales/diagnóstico , Enfermedades Fetales/genética , Adolescente , Adulto , Femenino , Humanos , Análisis por Micromatrices , Persona de Mediana Edad , Fenotipo , Embarazo , Resultado del Embarazo , Diagnóstico Prenatal , Estudios Retrospectivos , Adulto Joven
6.
Geophys Res Lett ; 46(24): 14826-14835, 2019 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33012881

RESUMEN

During winter in the mid-latitudes, photochemical oxidation is significantly slower than in summer and the main radical oxidants driving formation of secondary pollutants, such as fine particulate matter and ozone, remain uncertain, owing to a lack of observations in this season. Using airborne observations, we quantify the contribution of various oxidants on a regional basis during winter, enabling improved chemical descriptions of wintertime air pollution transformations. We show that 25-60% of NOx is converted to N2O5 via multiphase reactions between gas-phase nitrogen oxide reservoirs and aerosol particles, with ~93% reacting in the marine boundary layer to form >2.5 ppbv ClNO2. This results in >70% of the oxidizing capacity of polluted air during winter being controlled, not by typical photochemical reactions, but from these multiphase reactions and emissions of volatile organic compounds, such as HCHO, highlighting the control local anthropogenic emissions have on the oxidizing capacity of the polluted wintertime atmosphere.

7.
J Perinatol ; 36(10): 823-7, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27309629

RESUMEN

OBJECTIVE: The objective of this study was to determine whether arrhythmia in the setting of maternal cardiac disease (MCD) affects perinatal outcomes. STUDY DESIGN: This is a retrospective cohort study of pregnant women with MCD who delivered during 2008 to 2013. Perinatal outcomes among women with an arrhythmia were compared with those without. RESULTS: Among 143 women, 36 (25%) had an arrhythmia. Those with an arrhythmia were more likely to have a spontaneous vaginal delivery (64 vs 43%, P<0.05) and required fewer operative vaginal births (8 vs 27%, P=0.02). Pregnancies were more likely to be complicated by intrauterine growth restriction (IUGR) (17 vs 5%, P<0.05), although there were no differences in the rate of small for gestational age. The risk of IUGR remained increased after controlling for confounding (adjusted odds ratio 6.98, 95% confidence interval 1.59 to 30.79, P=0.01). Two cases of placental abruption were identified among mothers with arrhythmia while none were identified in the controls (P<0.05). CONCLUSION: Patients with arrhythmias were more likely to have a spontaneous vaginal delivery. Our data suggest that these pregnancies were an increased risk for IUGR.


Asunto(s)
Arritmias Cardíacas/complicaciones , Complicaciones Cardiovasculares del Embarazo , Desprendimiento Prematuro de la Placenta/etiología , Adulto , Arritmias Cardíacas/epidemiología , Estudios de Casos y Controles , Parto Obstétrico/efectos adversos , Femenino , Retardo del Crecimiento Fetal/etiología , Humanos , Recién Nacido , Recien Nacido Prematuro , Embarazo , Complicaciones Cardiovasculares del Embarazo/epidemiología , Atención Prenatal/métodos , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
8.
Plant Biol (Stuttg) ; 17(2): 361-72, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25262794

RESUMEN

Rising temperatures and more frequent and severe climatic extremes as a consequence of climate change are expected to affect growth and distribution of tree species that are adapted to current local conditions. Species distribution models predict a considerable loss of habitats for Pinus sylvestris. These models do not consider possible intraspecific differences in response to drought and warming that could buffer those impacts. We tested 10 European provenances of P. sylvestris, from the southwestern to the central European part of the species distribution, for their response to warming and to drought using a factorial design. In this common-garden experiment the air surrounding plants was heated directly to prevent excessive soil heating, and drought manipulation, using a rain-out shelter, permitted almost natural radiation, including high light stress. Plant responses were assessed as changes in phenology, growth increment and biomass allocation. Seedlings of P. sylvestris revealed a plastic response to drought by increased taproot length and root-shoot ratios. Strongest phenotypic plasticity of root growth was found for southwestern provenances, indicating a specific drought adaptation at the cost of overall low growth of aboveground structures even under non-drought conditions. Warming had a minor effect on growth but advanced phenological development and had a contrasting effect on bud biomass and diameter increment, depending on water availability. The intraspecific variation of P. sylvestris provenances could buffer climate change impacts, although additional factors such as the adaptation to other climatic extremes have to be considered before assisted migration could become a management option.


Asunto(s)
Pinus sylvestris/fisiología , Plantones/crecimiento & desarrollo , Adaptación Fisiológica , Biomasa , Cambio Climático , Sequías , Ecosistema , Europa (Continente) , Pinus sylvestris/genética , Pinus sylvestris/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Tallos de la Planta/fisiología , Temperatura
9.
Int J Biometeorol ; 57(3): 391-400, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22710742

RESUMEN

In light of heightened interest in the response of pollen phenology to temperature, we investigated recent changes to the onset of Betula (birch) pollen seasons in central and southern England, including a test of predicted advancement of the Betula pollen season for London. We calculated onset of birch pollen seasons using daily airborne pollen data obtained at London, Plymouth and Worcester, determined trends in the start of the pollen season and compared timing of the birch pollen season with observed temperature patterns for the period 1995-2010. We found no overall change in the onset of birch pollen in the study period although there was evidence that the response to temperature was nonlinear and that a lower asymptotic start of the pollen season may exist. The start of the birch pollen season was strongly correlated with March mean temperature. These results reinforce previous findings showing that the timing of the birch pollen season in the UK is particularly sensitive to spring temperatures. The climate relationship shown here persists over both longer decadal-scale trends and shorter, seasonal trends as well as during periods of 'sign-switching' when cooler spring temperatures result in later start dates. These attributes, combined with the wide geographical coverage of airborne pollen monitoring sites, some with records extending back several decades, provide a powerful tool for the detection of climate change impacts, although local site factors and the requirement for winter chilling may be confounding factors.


Asunto(s)
Betula , Polen , Clima , Cambio Climático , Inglaterra , Estaciones del Año , Temperatura
10.
Int J Biometeorol ; 56(6): 1103-11, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22382508

RESUMEN

To date, phenological research has provided evidence that climate warming is impacting both animals and plants, evidenced by the altered timing of phenophases. Much of the evidence supporting these findings has been provided by analysis of historic records and present-day fieldwork; herbaria have been identified recently as an alternative source of phenological data. Here, we used Rubus specimens to evaluate herbaria as potential sources of phenological data for use in climate change research and to develop the methodology for using herbaria specimens in phenological studies. Data relevant to phenology (collection date) were recorded from the information cards of over 600 herbarium specimens at Ireland's National Herbarium in Dublin. Each specimen was assigned a score (0-5) corresponding to its phenophase. Temperature data for the study period (1852 - 2007) were obtained from the University of East Anglia's Climate Research Unit (CRU); relationships between temperature and the dates of first flower, full flower, first fruit and full fruit were assessed using weighted linear regression. Of the five species of Rubus examined in this study, specimens of only one (R. fruticosus) were sufficiently abundant to yield statistically significant relationships with temperature. The results revealed a trend towards earlier dates of first flower, full flower and first fruit phenophases with increasing temperature. Through its multi-phenophase approach, this research serves to extend the most recent work-which validated the use of herbaria through use of a single phenophase-to confirm herbarium-based research as a robust methodology for use in future phenological studies.


Asunto(s)
Cambio Climático/historia , Rosaceae/fisiología , Flores/fisiología , Frutas/fisiología , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Irlanda , Periodicidad , Temperatura
11.
BJOG ; 119(4): 402-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22251443

RESUMEN

OBJECTIVE: To compare the annual incidence rates of caesarean delivery between induction of labour and expectant management in the setting of macrosomia. DESIGN: This is a retrospective cohort study. SETTING: Deliveries in the USA in 2003. POPULATION: Singleton births of macrosomic neonates to low-risk nulliparous women at 39 weeks of gestation and beyond. METHODS: Women who had induction of labour at 39 weeks of gestation with a neonatal birthweight of 4000 ± 125 g (3875-4125 g) were compared with women who delivered (either induced or spontaneous labour) at 40, 41 or 42 weeks (i.e. expectant management), assuming an intrauterine fetal weight gain of 200 g per additional week of gestation. Similar comparisons were made at 40 and 41 weeks of gestation. Chi-square test and multivariable logistic regression analysis were used for statistical comparison. MAIN OUTCOME MEASURES: Method of delivery, 5-minute Apgar scores, neonatal injury. RESULTS: There were 132,112 women meeting the study criteria. In women whose labours were induced at 39 weeks and who delivered a neonate with a birthweight of 4000 ± 125 g, the frequency of caesarean was lower compared with women who delivered at a later gestational age (35.2% versus 40.9%; adjusted OR 1.25, 95% CI 1.17-1.33). This trend was maintained at both 40 weeks (36.1% versus 42.6%; adjusted OR 1.31, 95% CI 1.23-1.40) and 41 weeks (38.9% versus 41.8%; adjusted OR 1.16, 95% CI 1.06-1.28) of gestation. CONCLUSIONS: In the setting of known birthweight, it appears that induction of labour may reduce the risk of caesarean delivery. Future research should concentrate on clinical and radiological methods to better estimate birthweight to facilitate improved clinical care. These findings deserve examination in a large, prospective, randomised trial.


Asunto(s)
Cesárea/estadística & datos numéricos , Macrosomía Fetal/prevención & control , Trabajo de Parto Inducido/estadística & datos numéricos , Adulto , Distribución de Chi-Cuadrado , Estudios de Cohortes , Femenino , Peso Fetal , Humanos , Modelos Logísticos , Embarazo , Resultado del Embarazo , Tercer Trimestre del Embarazo , Prevalencia , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiología
12.
Ultrasound Obstet Gynecol ; 37(3): 324-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20812377

RESUMEN

OBJECTIVE: To examine the diagnostic precision of ultrasound examination for placenta accreta in women with placenta previa and to compare the morbidity associated with accreta to that of previa alone. METHODS: This was a retrospective cohort study of all women with previa with/without accreta examined at the University of California, San Francisco (UCSF) between 2002 and 2008. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of ultrasound examination for the diagnosis of accreta were calculated and compared with results from similar studies in the literature. Univariable analysis was used to compare clinical outcomes. RESULTS: The PPV of an ultrasound diagnosis of accreta was 68% and NPV was 98%. Ultrasound had a sensitivity of 89.5%. Compared with previa alone, accreta had an odds ratio (OR) of 89.6 (95% CI, 19.44-412.95) for estimated blood loss > 2 L, an OR of 29.6 (95% CI, 8.20-107.00) for transfusion and an OR of 8.52 (95% CI, 2.58-28.11) for length of hospital stay > 4 days. CONCLUSION: Placenta accreta is associated with greater morbidity than is placenta previa alone. Ultrasound examination is a good diagnostic test for accreta in women with placenta previa. This is consistent with most other studies in the literature.


Asunto(s)
Cesárea Repetida/efectos adversos , Placenta Accreta/diagnóstico por imagen , Placenta Previa/diagnóstico por imagen , Hemorragia Posparto/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Histerectomía , Placenta Accreta/etiología , Placenta Previa/etiología , Hemorragia Posparto/etiología , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos , Factores de Riesgo , San Francisco , Sensibilidad y Especificidad , Ultrasonografía Prenatal/métodos
13.
Science ; 316(5821): 71, 2007 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-17412949

RESUMEN

Information on responses of higher organisms to climate change is dominated by events in spring. Far less is known about autumnal events and virtually nothing about communities of microorganisms. We analyzed autumnal fruiting patterns of macrofungi over the past 56 years and found that average first fruiting date of 315 species is earlier, while last fruiting date is later. Fruiting of mycorrhizal species that associate with both deciduous and coniferous trees is delayed in deciduous, but not in coniferous, forests. Many species are now fruiting twice a year, indicating increased mycelial activity and possibly greater decay rates in ecosystems.


Asunto(s)
Ecosistema , Cuerpos Fructíferos de los Hongos/crecimiento & desarrollo , Hongos/crecimiento & desarrollo , Micorrizas/crecimiento & desarrollo , Inglaterra , Estaciones del Año , Temperatura , Factores de Tiempo , Tracheophyta/microbiología , Árboles/microbiología
14.
Int J Biometeorol ; 50(5): 275-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16402207

RESUMEN

In 1944, John Willis produced a summary of his meticulous record keeping of weather and plants over the 30 years 1913-1942. This publication contains fixed-date, fixed-subject photography taken on the 1st of each month from January to May, using as subjects snowdrop Galanthus nivalis, daffodil Narcissus pseudo-narcissus, horse chestnut Aesculus hippocastanum and beech Fagus sylvatica. We asked 38 colleagues to assess rapidly the plant development in each of these photographs according to a supplied five-point score. The mean scores from this exercise were assessed in relation to mean monthly weather variables preceding the date of the photograph and the consistency of scoring was examined according to the experience of the recorders. Plant development was more strongly correlated with mean temperature than with minimum or maximum temperatures or sunshine. No significant correlations with rainfall were detected. Whilst mean scores were very similar, botanists were more consistent in their scoring of developmental stages than non-botanists. However, there was no overall pattern for senior staff to be more consistent in scoring than junior staff. These results suggest that scoring of plant development stages on fixed dates could be a viable method of assessing the progress of the season. We discuss whether such recording could be more efficient than traditional phenology, especially in those sites that are not visited regularly and hence are less amenable to frequent or continuous observation to assess when a plant reaches a particular growth stage.


Asunto(s)
Fotograbar/métodos , Fenómenos Fisiológicos de las Plantas , Clima , Estaciones del Año , Temperatura , Factores de Tiempo , Tiempo (Meteorología)
15.
Int J Biometeorol ; 49(4): 262-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15538637

RESUMEN

Our data, collected in the extreme east of Europe, show that a significant biological effect of climate change has been experienced even in territories where temperature increase has been the lowest. This study documents the climatic response of pedunculate oak (Quercus robur) growing near its north-eastern limits in Europe. It demonstrates the potential of oak trees in old-growth forest to act as proxy climate indicators. Many factors may influence the temporal stability of the growth-climate, acorn crop-climate and first leafing-climate relationships. Climate data, climatic fluctuations, reproduction, genetics and tree-age may relate to this instability. Our results stress that an increase in climate variability or climatic warming resulting from warmer winters or summers could affect the oak population in eastern Europe in a similar way to that in western Europe. These findings, from remnants of oak forest in the middle Volga region of Russia, allow a further understanding of how species could be affected by future climates.


Asunto(s)
Clima , Quercus/crecimiento & desarrollo , Aclimatación , Nueces/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrollo , Lluvia , Federación de Rusia , Temperatura
16.
Arch Environ Contam Toxicol ; 45(1): 136-47, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12948183

RESUMEN

Livers from 121 birds killed in mortality incidents in U.K. coastal waters between 1991 and 1996 were analyzed for 16 PCB congeners (IUPAC numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180). Species analyzed were guillemot (Uria aalge), shag (Phalacrocorax arisotelis), kittiwake (Rissa tridactyla), puffin (Fratercula arctica), razorbill (Alca torda), fulmar (Fulmarus glacialis), gannet (Sula bassana), and herring gull (Larus argentatus). This is the first report of PCBs in U.K. seabird tissues to be presented since 1983. Mean concentrations of total PCBs ranged from 0.47 to 15.8 mg/kg WW, similar to concentrations reported for North Sea birds during the 1970s and 1980s and lower than those reported for the same species in the Irish Sea during the late 1960s and early 1970s. The congeners generally present in the highest concentrations were (in decreasing order) 153, 138, 180, 118, and 170. Despite the birds having similar diets, both inter- and intraspecies differences in PCB congener profile were found. In guillemots from several sites on the east coast, the dominant congener was 138, compared to guillemots from the south coast, which had the more typical congener pattern found in seabirds. Some of the differences in total PCB values could be due to different causes of death, with a subsequent effect on body lipid levels.


Asunto(s)
Aves , Contaminantes Ambientales/farmacocinética , Bifenilos Policlorados/farmacocinética , Animales , Composición Corporal , Causas de Muerte , Contaminantes Ambientales/análisis , Femenino , Lípidos/análisis , Hígado/química , Masculino , Bifenilos Policlorados/análisis , Dinámica Poblacional , Reino Unido
17.
Pest Manag Sci ; 57(10): 896-905, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11695182

RESUMEN

The spinosyns, a novel family of insecticidal macrocyclic lactones, are active on a wide variety of insect pests, especially lepidopterans and dipterans. The biological activity of a mixture (spinosad; Tracer, Spin-Tor, Success) of the two most abundant spinosyns (spinosyns A and D) against pest insects is on a par with that of many pyrethroid insecticides. The spinosyns also exhibit a very favorable environmental and toxicological profile, and possess a mode of action that appears unique, with studies to date suggesting that both nicotinic and gamma-aminobutryic acid receptor functions are altered in a novel manner. Compared to pyrethroids such as cypermethrin, spinosyn A is slow to penetrate into insect larvae such as tobacco budworm larvae (Heliothis virescens); however, once inside the insect, spinosyn A is not readily metabolized. To date, more than 20 spinosyns and more than 800 spinosoids (semi-synthetic analogs) have been isolated or synthesized, respectively. Artificial neural network-based quantitative structure activity relationship (QSAR) studies for the spinosyns suggested that modification of the 2',3',4'-tri-O-methylrhamnosyl moiety could improve activity and several spinosoids incorporating these modifications exhibited markedly improved lepidopteran activity compared to spinosad. Multiple linear regression-based QSAR studies also suggest that whole molecule properties such as CLogP and MOPAC dipole moment can explain much of the biological activity observed for the spinosyns and closely related spinosoids.


Asunto(s)
Insectos/efectos de los fármacos , Insecticidas/toxicidad , Macrólidos/toxicidad , Permetrina/toxicidad , Piretrinas/toxicidad , Animales , Productos Biológicos , Combinación de Medicamentos , Insecticidas/química , Macrólidos/química , Modelos Biológicos , Permetrina/química , Piretrinas/química , Relación Estructura-Actividad Cuantitativa , Conejos , Ratas
18.
Pest Manag Sci ; 57(2): 177-85, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11455648

RESUMEN

The spinosyns are a new class of fermentation-derived insect control agents that are effective against a variety of chewing insect pests. The successful introduction of spinosad into the agricultural marketplace represents an important milestone in the use of natural products for commercial pest control. The development of a natural product presents additional limitations relative to a synthetic material. While the latter affords some degree of control in building appropriate physical attributes such as photostability, a natural product, designed to function in a different environment, is often less suited for traditional spray applications. Despite its intrinsic photolability, spinosad is stable enough to perform under field conditions. In an effort to generate analogs with improved physical characteristics, we have developed a variety of conditions for selectively modifying different portions of the molecule, and we have discovered analogs with greater activity against a broader spectrum of pests. The inability to translate improved greenhouse activity to actual field conditions resulted in a detailed study of the effects of formulations and crystallinity on biological activity. Through this effort, measurably improved field performance of synthetic spinosyn analogs relative to the natural product have now been observed.


Asunto(s)
Control de Insectos , Insecticidas/química , Macrólidos/síntesis química , Animales , Antibacterianos/química , Bioensayo , Química Agrícola/métodos , Productos Agrícolas/metabolismo , Cristalización , Combinación de Medicamentos , Fermentación , Insecticidas/metabolismo , Insecticidas/farmacología , Macrólidos/metabolismo , Macrólidos/farmacología , Estructura Molecular , Fotólisis
19.
Int J Biometeorol ; 45(4): 212-6, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11769323

RESUMEN

The (barn) swallow Hirundo rustica is a traditional harbinger of spring in many countries of the Northern Hemisphere. This paper uses information on the arrival and departure dates of the swallow in the Slovak Republic for the 30 years 1961-1985 and 1996-2000. Records were taken at 19 locations throughout the Republic representing an altitude range from 105 m to 760 m. Monthly temperature data were constructed from six meteorological stations. With the use of regression techniques, trends towards later arrival, earlier departure and the effects of latitude, altitude and temperature are all apparent.


Asunto(s)
Altitud , Fenómenos de Retorno al Lugar Habitual , Pájaros Cantores , Temperatura , Adaptación Fisiológica , Animales , Femenino , Masculino , Eslovaquia , Factores de Tiempo
20.
Int J Biometeorol ; 45(4): 217-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11769324

RESUMEN

Many analyses do not consider the problems associated with the effects of population size on encounter recording. Population size could impact on the detection of bird arrival time as there is a higher probability of observing earlier arrival when the population size is greater and the song activity of birds is increased, as occurs with a larger population. As a case study, we have analysed data on the red-backed shrike Lanius collurio collected in Western Poland during 1983-2000. In this period the red-backed shrike's return to its breeding sites became significantly earlier whilst the contemporary population size increased significantly. To eliminate linear trends through time we have worked on the standardised residuals from regression of both arrival time and population size on year. The correlation between arrival time and population size residuals was significantly negative, further supporting the link between detection and population size. This finding suggests that, in studies of avian migration and its changes over time, the relationship between arrival date and population size needs to be considered.


Asunto(s)
Clima , Fenómenos de Retorno al Lugar Habitual , Pájaros Cantores , Animales , Dinámica Poblacional , Estaciones del Año , Factores de Tiempo
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