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1.
Bioscience ; 73(3): 168-181, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36936381

RESUMO

Bioblitzes are a popular approach to engage people and collect biodiversity data. Despite this, few studies have actually evaluated the multiple outcomes of bioblitz activities. We used a systematic review, an analysis of data from more than 1000 bioblitzes, and a detailed analysis of one specific bioblitz to inform our inquiry. We evaluated five possible bioblitz outcomes, which were creating a species inventory, engaging people in biological recording, enhancing learning about nature, discovering a species new to an area, and promoting an organization. We conclude that bioblitzes are diverse but overall effective at their aims and have advantages over unstructured biodiversity recording. We demonstrate for the first time that bioblitzes increase the recording activity of the participants for several months after the event. In addition, we provide evidence that bioblitzes are effective at bringing people and organizations together to build communities of professionals and amateurs, critical for conserving and protecting biodiversity.

2.
Conserv Biol ; 37(1): e13965, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35686511

RESUMO

Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.


Las catarinas (Coleoptera: Coccinellidae) proporcionan servicios que son críticos para la producción de alimento, y juegan un papel ecológico como fuente de alimento para depredadores. Sin embargo, la riqueza, abundancia y distribución de catarinas están en peligro debido a muchas amenazas antropogénicas. La carencia de conocimiento sobre el estatus de conservación de la mayoría de las especies y los factores que inciden en su dinámica poblacional dificulta el desarrollo e implementación de estrategias de conservación para las catarinas. Realizamos una revisión de la literatura sobre la ecología, diversidad y conservación de catarinas para identificar sus amenazas ecológicas clave. Las poblaciones de catarinas fueron afectadas mayormente por factores climáticos, composición del paisaje e invasiones biológicas. Proponemos acciones de mitigación para la conservación y recuperación de catarinas. Acciones a corto plazo incluyen programas de ciencia y educación ciudadana, medidas de protección para la recuperación de hábitat y de especies amenazadas, prevención de la introducción de especies no nativas y el mantenimiento y restauración de áreas naturales y la heterogeneidad del paisaje. Acciones a mediano plazo implican el análisis de datos obtenidos de programas de monitoreo y colecciones de insectos para desenmarañar el efecto de las diferentes amenazas a las poblaciones de catarinas, comprender el uso del hábitat por taxa de los que se tiene conocimiento limitado y cuantifica las tendencias temporales de la abundancia, diversidad y biomasa a lo largo de un gradiente de intensidad de manejo. Acciones a largo plazo incluyen el desarrollo de un programa de monitoreo a nivel mundial basado en muestreos estandarizados para subsanar la falta de datos, incrementar el poder explicativo, optimizar los análisis y facilitar colaboraciones globales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Espécies em Perigo de Extinção , Dinâmica Populacional
3.
Ecol Entomol ; 40(4): 336-348, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26435571

RESUMO

1. Harmonia axyridis was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003. 2. The UK Ladybird Survey, a citizen science initiative involving online recording, was launched in 2005 to encourage people across Britain to track the spread of H. axyridis. Tens of thousands of people have provided records of H. axyridis and other species of ladybirds, creating an invaluable dataset for large-scale and long-term research. Declines in the distribution of seven (of eight assessed) native species of ladybird have been demonstrated, and correlated with the arrival of H. axyridis, using the records collated through the UK Ladybird Survey. 3. Experimental research and field surveys have also contributed to our understanding of the ecology of H. axyridis and particularly the process of invasion. Harmonia axyridis arrived in Britain through dispersal and introduction events from regions in which it was deliberately released as a biological control agent. The rapid spread of this species has been attributed to its high natural dispersal capability by means of both flight and anthropogenic transport. A number of factors have contributed to the successful establishment and indeed dominance of this polymorphic species within aphidophagous guilds, including high reproductive capacity, intra-guild predation, eurytopic nature, high resistance to natural enemies within the invaded range, and potentially phenotypic plasticity. 4. The global invasion by H. axyridis and subsequent research on this species has contributed to the general understanding of biological invasions.

4.
Ecology ; 95(1): 197-209, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24649659

RESUMO

Extensive changes in montane forest structure have occurred throughout the U.S. Southwest following Euro-American settlement. These changes are a product of confounding effects of disturbance, climate variability, species competition, and modern land use changes. Pronounced forest reproduction events in the Southwest have generally occurred in climatically wet periods but have also followed widespread fire exclusion. Understanding the ecological processes driving such events has important implications for forest restoration, although these efforts remain difficult due to confounding factors. Separation of these interacting factors was possible in the Sierra San Luis of northern Mexico where we investigated climate, fire, and tree recruitment in areas with continued frequent fires or where fire exclusion came relatively late (1940s). Fires were strongly tied to interannual wet-dry cycles of climate, whereas recruitment peaks were more closely tied to local processes, namely, fire-free periods, than to broad-scale climatically wet conditions. The greatest pulse of tree recruitment coincided with a pronounced mid-century drought (1942-1957) and a period of reduced fire frequency. The second largest pulse of recruitment (ca. 1900) preceded a well-documented period of recruitment (and an anomalously wet period) elsewhere across the Southwest in the 1910s-1920s, and also coincided with specific fire-free periods during below-average precipitation. We also found greater spatial dependence and clustering in older age classes of trees. This spatial pattern indicates a legacy of fire-induced mortality in shaping stand structure, underscoring the importance of frequent fire effects on spatial variability in forests.


Assuntos
Clima , Ecossistema , Incêndios , Árvores/fisiologia , México , Dinâmica Populacional , Fatores de Tempo
5.
Wellcome Open Res ; 9: 106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966305

RESUMO

We present a genome assembly from an individual male Adalia decempunctata (the ten-spot ladybird; Arthropoda; Insecta; Coleoptera; Coccinellidae). The genome sequence is 489.4 megabases in span. Most of the assembly is scaffolded into 12 chromosomal pseudomolecules, including the X and Y sex chromosomes. The mitochondrial genome has also been assembled and is 19.68 kilobases in length.

6.
Am J Pathol ; 181(1): 313-21, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22595380

RESUMO

Abdominal aortic aneurysm (AAA) pathogenesis is distinguished by vessel wall inflammation. Cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase-1, key components of the most well-characterized inflammatory prostaglandin pathway, contribute to AAA development in the 28-day angiotensin II infusion model in mice. In this study, we used this model to examine the role of the prostaglandin E receptor subtype 4 (EP4) and genetic knockdown of COX-2 expression (70% to 90%) in AAA pathogenesis. The administration of the prostaglandin receptor EP4 antagonist AE3-208 (10 mg/kg per day) to apolipoprotein E (apoE)-deficient mice led to active drug plasma concentrations and reduced AAA incidence and severity compared with control apoE-deficient mice (P < 0.01), whereas COX-2 genetic knockdown/apoE-deficient mice displayed only a minor, nonsignificant decrease in incidence of AAA. EP4 receptor protein was present in human and mouse AAA, as observed by using Western blot analysis. Aortas from AE3-208-treated mice displayed evidence of a reduced inflammatory phenotype compared with controls. Atherosclerotic lesion size at the aortic root was similar between all groups. In conclusion, the prostaglandin E(2)-EP4 signaling pathway plays a role in the AAA inflammatory process. Blocking the EP4 receptor pharmacologically reduces both the incidence and severity of AAA in the angiotensin II mouse model, potentially via attenuation of cytokine/chemokine synthesis and the reduction of matrix metalloproteinase activities.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Receptores de Prostaglandina E Subtipo EP4/fisiologia , Adulto , Angiotensina II , Animais , Aorta/metabolismo , Aorta/patologia , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/prevenção & controle , Ruptura Aórtica/prevenção & controle , Aterosclerose/patologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Naftalenos/farmacologia , Naftalenos/uso terapêutico , Fenilbutiratos/farmacologia , Fenilbutiratos/uso terapêutico , Receptores de Prostaglandina E Subtipo EP4/antagonistas & inibidores , Receptores de Prostaglandina E Subtipo EP4/deficiência , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais/fisiologia , Ultrassonografia
7.
Wellcome Open Res ; 8: 186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37476650

RESUMO

We present a genome assembly from an individual Halyzia sedecimguttata (the orange ladybird, Arthropoda; Insecta; Coleoptera, Coccinellidae). The genome sequence is 919.1 megabases in span. Most of the assembly is scaffolded into 10 chromosomal pseudomolecules, including the X sex chromosome. The mitochondrial genome has also been assembled and is 21.0 kilobases in length. Gene annotation of this assembly on Ensembl identified 27,547 protein coding genes.

8.
Tree Physiol ; 41(10): 1893-1905, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-33823053

RESUMO

Tracking wood formation in semiarid regions during the seasonal march of precipitation extremes has two important applications. It can provide (i) insight into the adaptive capacities of trees to drought and (ii) a basis for a richer interpretation of tree-ring data, assisting in a deeper understanding of past and current climate. In the southwestern USA, the anatomical signature of seasonally bimodal precipitation is the 'false ring'-a band of latewood-like cells in the earlywood. These occur when a particularly deep drought during the early growing season ends abruptly with timely, mid-growing season monsoonal rains. Such conditions presented in southern Arizona in 2014, enabling us to explore false-ring formation in ponderosa pine (Pinus ponderosa Lawson and C. Lawson) and Douglas-fir (Pseudotsuga menziesii Mirb. Franco) in mixed-conifer forest at 2573 m above sea level. We ask: what were the cell-by-cell timings and durations in the phases of wood cell development in 2014? How do these seasonal patterns relate to strongly fluctuating environmental conditions during the growing season? We took weekly microcores from March through November from six ponderosa pine and seven Douglas-fir trees at a well-instrumented flux tower site. Thin sections were prepared, and we counted cells in cambial, expansion, cell wall thickening and mature phases. For ponderosa pine trees forming a false ring, the first impact of intensifying seasonal drought was seen in the enlarging phase and then, almost a month later, in cambial activity. In this species, recovery from drought was associated with recovery first in cambial activity, followed by cell enlargement. This timing raised the possibility that cell division may be affected by atmospheric moisture increases before soil recharge. In both species, the last false-ring cells matured during the summer rainy season. Bimodal cambial activity coincident with moisture availability was observed in both species, whether or not they formed a false ring. This deeper knowledge of the precise timing of both developmental and environmental events should help define mechanistic connections among these factors in creating bimodal growth patterns.


Assuntos
Pinus ponderosa , Pseudotsuga , Arizona , Clima , Pinus ponderosa/crescimento & desenvolvimento , Pseudotsuga/crescimento & desenvolvimento , Chuva , Árvores/crescimento & desenvolvimento
9.
Ecology ; 91(6): 1660-71, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20583708

RESUMO

The El Niño Southern Oscillation (ENSO) is a climate-forcing mechanism that has been shown to affect precipitation and the occurrence of wildfires in many parts of the world. In the southern United States and northern Mexico, warm events (El Niño) are associated with moist winter conditions and fewer fires, while cool events (La Niñia) tend to favor dry winters and more fires. We tested this relationship in a region of northeastern Mexico by characterizing the historical fire regime and climatic influences: Fire regimes were reconstructed from fire-scar samples collected from 100 trees in three high-elevation sites on Peña Nevada in southern Nuevo Le6n. The sites were approximately 25 ha each, and the site centers were approximately 1 km apart. The earliest recorded fire occurred in 1521 and the time period we used for analysis was 1645-1929. The sites were characterized by frequent surface fires before the 1920s. In the three sites, mean fire intervals ranged from 8.6 to 9.6 years (all fires) and 11.9 to 18.6 years (fires that scarred > or = 25% of recording trees). The per-tree mean fire return interval was 17 years, and all three sites burned in the same year seven times between 1774 and 1929. After 1929, fires were nearly eliminated in all sites, likely due to human causes. We found a temporal change in the association between ENSO events and fires; before the 1830s La Niña events were significantly associated with fire years, while after the 1830s this association was not significant. In 1998, when the most severe El Niño event of the past century occurred, the three sites experienced severe, stand-replacing fires that killed many trees that had survived multiple surface fires in the past. Prior to the 1830s, fires tended to occur during dry La Niña years, but since then both La Niña and El Niño have been associated with dry years in this region, especially during the last three decades. This result suggests that ENSO effects have changed over time in this location and that phases of ENSO are not consistent indicators of precipitation, fire occurrence, or fire behavior in this area of northeastern Mexico.


Assuntos
Clima , Ecossistema , Incêndios , México , Fatores de Tempo
10.
Biol Res Nurs ; 22(1): 24-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31684758

RESUMO

Patients with peripheral artery disease (PAD), consistent with others with atherosclerotic occlusive disorders, have autonomic dysfunction (as measured by low heart rate variability [HRV]) that predisposes them to sympathetically mediated cardiac arrhythmias and sudden death. Exercise therapy has been shown to increase HRV in patients with coronary artery disease by increasing parasympathetic modulation of heart rate. This study quantified the circulatory and autonomic effects of a progressive, 12-week home-based, low-intensity (pain-free walking) exercise program in PAD and intermittent claudication. Participants (N = 33, mean age 67.8 8.1 years) were randomly assigned to either a walking group (n = 18), whose members performed a structured, 12-week, progressive walking program 5 days/week for 12 weeks, or a comparison group (n = 15), whose members performed usual activities. Circulatory measures (heart rate, blood pressure, and rate pressure product) and autonomic measures (HRV) were obtained at the beginning (Week 1) and end (Week 12) of the study. Minimal change in circulatory measures occurred. However, spectral analysis of HRV revealed that autonomic function improved significantly in members of the walking group; specifically, there was an increase in parasympathetic and a decrease in sympathetic modulation. Members of the walking group also significantly increased maximal walking distance. These findings suggest that a structured, low-intensity, high-frequency walking program improves autonomic function by increasing HRV in patients with PAD.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Claudicação Intermitente/fisiopatologia , Doença Arterial Periférica/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
11.
Biochem J ; 416(2): 281-8, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18637789

RESUMO

The modification of proteins by reducing sugars through the process of non-enzymatic glycation is one of the principal mechanisms by which hyperglycaemia may precipitate the development of diabetic complications. Fn3K (fructosamine 3-kinase) and Fn3KRP (Fn3K-related protein) are two recently discovered enzymes that may play roles in metabolizing early glycation products. However, although the activity of these enzymes towards various glycated substrates has been established, very little is known about their structure-function relationships or their respective mechanisms of action. Furthermore, their only structural similarities noted to date with members of other kinase families has been with the bacterial aminoglycoside kinases. In the present study, we employed affinity labelling with the ATP analogue FSBA {5'-p-[(fluorosulfonyl)benzoyl]adenosine} to probe the active-site topology of Fn3KRP as an example of this enigmatic family of kinases. FSBA was found to modify Fn3KRP at five distinct sites; four of these were predicted to be localized in close proximity to its ATP-binding site, based on alignments with the aminoglycoside kinase APH(3')-IIIa, and examination of its published tertiary structure. The results of the present studies provide evidence that Fn3KRP possesses an ATP-binding domain that is structurally related to that of both the aminoglycoside kinases and eukaryotic protein kinases.


Assuntos
Trifosfato de Adenosina/metabolismo , Adenosina/análogos & derivados , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Adenosina/farmacologia , Marcadores de Afinidade/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Primers do DNA , Glicosilação , Humanos , Canamicina Quinase/metabolismo , Neoplasias Pulmonares , Muramidase/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/química , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Quinases/metabolismo , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tripsina
12.
Ecology ; 100(11): e02839, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31330049

RESUMO

A key challenge to maintaining resilient landscapes is adapting to and maintaining dynamic ecological processes. In fire-dependent ecosystems, this includes identifying and defining mechanisms through which fire influences forest structure and functionality. Interpretations of tree patterns via land survey records in the Lake States have often highlighted the importance of infrequent moderate to extreme disturbance events. However, historical survey methods are limited to observing higher severity disturbances and over large landscapes, thus it is not clear if the origin, structure, and forcing factors for either patterns or processes are adequately quantified by these methods. We used dendrochronological methods to determine how fire history and stand structure, including cohort structure, tree density, and spatial patterning, are linked within Lake States mixed conifer forests in Wisconsin. We found relatively short mean fire return intervals (MFRIs) ranging from 6 to 13 yr with little variation in fire frequency among sites. Current densities of red-pine-dominated forests are 4-37 times historical (ca. 1860) densities (mean 12×) and almost entirely spatially random, whereas historically forests were spatially aggregated at stand scales. Stands also contained multiple and/or loosely defined cohort structures suggesting very different controls operating historically than currently. Heterogeneity that helped maintain ecosystem resilience in these ecosystems historically came from frequent fire disturbance processes that affected stand-scale forest resistance. This was likely the historical dynamic across fire-adapted transitional pine forests of the Lake States.


Assuntos
Incêndios , Traqueófitas , Ecossistema , Florestas , Árvores , Wisconsin
13.
Ecol Appl ; 18(8): 1984-99, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19263892

RESUMO

Mount Rushmore National Memorial in the Black Hills of South Dakota is known worldwide for its massive sculpture of four of the United States' most respected presidents. The Memorial landscape also is covered by extensive ponderosa pine (Pinus ponderosa) forest that has not burned in over a century. We compiled dendroecological and forest structural data from 29 plots across the 517-ha Memorial and used fire behavior modeling to reconstruct the historical fire regime and forest structure and compare them to current conditions. The historical fire regime is best characterized as one of low-severity surface fires with occasional (> 100 years) patches (< 100 ha) of passive crown fire. We estimate that only approximately 3.3% of the landscape burned as crown fire during 22 landscape fire years (recorded at > or = 25% of plots) between 1529 and 1893. The last landscape fire was in 1893. Mean fire intervals before 1893 varied depending on spatial scale, from 34 years based on scar-to-scar intervals on individual trees to 16 years between landscape fire years. Modal fire intervals were 11-15 years and did not vary with scale. Fire rotation (the time to burn an area the size of the study area) was estimated to be 30 years for surface fire and 800+ years for crown fire. The current forest is denser and contains more small trees, fewer large trees, lower canopy base heights, and greater canopy bulk density than a reconstructed historical (1870) forest. Fire behavior modeling using the NEXUS program suggests that surface fires would have dominated fire behavior in the 1870 forest during both moderate and severe weather conditions, while crown fire would dominate in the current forest especially under severe weather. Changes in the fire regime and forest structure at Mount Rushmore parallel those seen in ponderosa pine forests from the southwestern United States. Shifts from historical to current forest structure and the increased likelihood of crown fire justify the need for forest restoration before a catastrophic wildfire occurs and adversely impacts the ecological and aesthetic setting of the Mount Rushmore sculpture.


Assuntos
Incêndios/história , Árvores , Geografia , História do Século XIX , História do Século XX , História do Século XXI , Modelos Teóricos , Pinus ponderosa , South Dakota , Fatores de Tempo , Tempo (Meteorologia)
14.
Ecology ; 87(10): 2500-10, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17089659

RESUMO

Climate influences forest structure through effects on both species demography (recruitment and mortality) and disturbance regimes. Here, I compare multi-century chronologies of regional fire years and tree recruitment from ponderosa pine forests in the Black Hills of southwestern South Dakota and northeastern Wyoming to reconstructions of precipitation and global circulation indices. Regional fire years were affected by droughts and variations in both Pacific and Atlantic sea surface temperatures. Fires were synchronous with La Niñas, cool phases of the Pacific Decadal Oscillation (PDO), and warm phases of the Atlantic Multidecadal Oscillation (AMO). These quasi-periodic circulation features are associated with drought conditions over much of the western United States. The opposite pattern (El Niño, warm PDO, cool AMO) was associated with fewer fires than expected. Regional tree recruitment largely occurred during wet periods in precipitation reconstructions, with the most abundant recruitment coeval with an extended pluvial from the late 1700s to early 1800s. Widespread even-aged cohorts likely were not the result of large crown fires causing overstory mortality, but rather were caused by optimal climate conditions that contributed to synchronous regional recruitment and longer intervals between surface fires. Synchronous recruitment driven by climate is an example of the Moran effect. The presence of abundant fire-scarred trees in multi-aged stands supports a prevailing historical model for ponderosa pine forests in which recurrent surface fires affected heterogenous forest structure, although the Black Hills apparently had a greater range of fire behavior and resulting forest structure over multi-decadal time scales than ponderosa pine forests of the Southwest that burned more often.


Assuntos
Clima , Incêndios , Pinus ponderosa/crescimento & desenvolvimento , Cronologia como Assunto , Ecologia , Agricultura Florestal , South Dakota , Wyoming
15.
Artigo em Inglês | MEDLINE | ID: mdl-16880565

RESUMO

Myo-inositol oxygenase (MIOX) catalyzes the novel oxidative cleavage of myo-inositol (MI) and its epimer D-chiro inositol (DCI) to D-glucuronate. MIOX utilizes an Fe(II)/Fe(III) binuclear iron centre for the dioxygen-dependent cleavage of the C1-C6 bond in MI. Despite its key role in inositol metabolism, the structural basis of its unique four-electron oxidation mechanism and its substrate specificity remain unknown. In order to answer these questions and to facilitate the use of this key enzyme for the development of new therapeutic strategies for diabetes, the mouse enzyme has been cloned, expressed in Escherichia coli, purified and crystallized from 4.4 M sodium formate. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 44.87, b = 77.26, c = 84.84 angstroms, and diffract to 2.8 angstroms resolution.


Assuntos
Inositol Oxigenase/isolamento & purificação , Animais , Sequência de Bases , Configuração de Carboidratos , Cristalização , Primers do DNA , Escherichia coli/enzimologia , Escherichia coli/genética , Inositol/química , Inositol Oxigenase/química , Inositol Oxigenase/genética , Camundongos , Modelos Moleculares , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Difração de Raios X
16.
J Agric Food Chem ; 54(5): 1588-93, 2006 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-16506805

RESUMO

This study describes a generic biological screening assay designed to detect anticoagulant rodenticides based on their inhibitory action on the vitamin K epoxide reductase protein complex, resulting in an accumulation of under-carboxylated prothrombin or proteins induced by vitamin K antagonism (PIVKA-II). A combined cell culture/ELISA assay was optimized to measure PIVKA-II production by the human hepatoma HepG2 cell line cultured in the presence of anticoagulant rodenticides. The specificity and sensitivity of the assay was validated using 41 grain extracts containing representative concentrations of rodenticide or appropriate nonrodenticide control compounds. In all cases, PIVKA-II produced by HepG2 cells in response to grain extracts spiked with rodenticides was detected by ELISA, while PIVKA-II was not detected in supernatants collected from cells exposed to nonrodenticide controls. This represents a novel, class-specific biological assay for the detection of anticoagulant rodenticides present in contaminated grain.


Assuntos
Anticoagulantes/análise , Bioensaio , Grão Comestível/química , Ensaio de Imunoadsorção Enzimática/métodos , Indanos/farmacologia , Rodenticidas/análise , Anticoagulantes/farmacologia , Biomarcadores/análise , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Cumarínicos/análise , Cumarínicos/farmacologia , Contaminação de Alimentos/análise , Humanos , Indanos/análise , Neoplasias Hepáticas , Organofosfatos/farmacologia , Precursores de Proteínas/análise , Precursores de Proteínas/biossíntese , Protrombina/análise , Protrombina/biossíntese , Varfarina/análise , Varfarina/farmacologia
17.
Can Respir J ; 13(5): 266-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16896428

RESUMO

OBJECTIVE: To assess smoking policies at Canadian acute care hospitals. METHOD: A questionnaire was designed, piloted and faxed to all acute care hospitals in Canada. The questionnaire was designed to address the following: what is the current policy regarding patient smoking? Are staff and/or visitors allowed to smoke inside the hospital? Is there a separate policy for psychiatric patients? Are smoking cessation products available at the hospital pharmacy? Is the policy governed by regional or municipal legislation? RESULTS: A total of 852 hospitals were included in the study. Of these, 476 responded to the questionnaire, for an overall response rate of 56%. Twenty-seven per cent of respondents allowed patient smoking inside the hospital. While staff smoking was not allowed inside most hospitals (93%), 32% of hospitals in Quebec allowed staff to smoke inside the building. Thirty per cent of hospitals had a separate policy for psychiatric patients, and 27% of hospitals had provisions for visitor smoking. Sixty-seven per cent of hospitals were able to offer patients smoking cessation products while they were in hospital. CONCLUSIONS: Many Canadian hospitals continue to allow smoking inside their facilities. There is considerable variation in hospital smoking policies across the country.


Assuntos
Administração Hospitalar/normas , Política Organizacional , Prevenção do Hábito de Fumar , Canadá , Pesquisas sobre Atenção à Saúde , Administração Hospitalar/estatística & dados numéricos , Humanos , Pessoas Mentalmente Doentes , Pacientes , Recursos Humanos em Hospital , Abandono do Hábito de Fumar/métodos , Inquéritos e Questionários , Visitas a Pacientes
18.
PLoS One ; 11(3): e0151595, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27007973

RESUMO

Action to reduce anthropogenic impact on the environment and species within it will be most effective when targeted towards activities that have the greatest impact on biodiversity. To do this effectively we need to better understand the relative importance of different activities and how they drive changes in species' populations. Here, we present a novel, flexible framework that reviews evidence for the relative importance of these drivers of change and uses it to explain recent alterations in species' populations. We review drivers of change across four hundred species sampled from a broad range of taxonomic groups in the UK. We found that species' population change (~1970-2012) has been most strongly impacted by intensive management of agricultural land and by climatic change. The impact of the former was primarily deleterious, whereas the impact of climatic change to date has been more mixed. Findings were similar across the three major taxonomic groups assessed (insects, vascular plants and vertebrates). In general, the way a habitat was managed had a greater impact than changes in its extent, which accords with the relatively small changes in the areas occupied by different habitats during our study period, compared to substantial changes in habitat management. Of the drivers classified as conservation measures, low-intensity management of agricultural land and habitat creation had the greatest impact. Our framework could be used to assess the relative importance of drivers at a range of scales to better inform our policy and management decisions. Furthermore, by scoring the quality of evidence, this framework helps us identify research gaps and needs.


Assuntos
Agricultura , Biodiversidade , Mudança Climática , Reino Unido
19.
PLoS One ; 11(5): e0147688, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27196621

RESUMO

Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.


Assuntos
Incêndios , Florestas , Pinus ponderosa , Traqueófitas , América do Norte
20.
J AOAC Int ; 88(1): 204-20, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15759743

RESUMO

The United Kingdom Wildlife Incident Investigation Scheme (WIIS) investigates cases of suspected poisoning of wildlife, honey bees, and companion animals by pesticides. Together with field inquiries and veterinary post-mortem examinations, the analytical procedures presented here provide a comprehensive approach to the investigation of these cases. The paper covers selection of animal tissues for analysis and methods suitable for the analysis of honey bees and for various types of bait. Seven multiresidue methods cover around 130 pesticides, and methods are also described for a further 8 compounds. These methods are currently used on samples submitted to the Scheme in England and Wales.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Cromatografia/métodos , Poluentes Ambientais/intoxicação , Espectrometria de Massas/métodos , Praguicidas/intoxicação , Alumínio/química , Animais , Animais Selvagens , Anticoagulantes/farmacologia , Abelhas , Carbamatos/análise , Cromatografia Gasosa/instrumentação , Cromatografia em Gel , Cromatografia Líquida/instrumentação , Poluentes Ambientais/análise , Moela não Aviária/efeitos dos fármacos , Isoxazóis , Fígado/efeitos dos fármacos , Espectrometria de Massas/instrumentação , Organofosfatos/toxicidade , Organofosfonatos/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/intoxicação , Intoxicação/diagnóstico , Intoxicação/veterinária , Sílica Gel , Dióxido de Silício/química , Estômago/efeitos dos fármacos , Tetrazóis , Reino Unido
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