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1.
Cell ; 176(6): 1282-1294.e20, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30849372

RESUMO

Multiple signatures of somatic mutations have been identified in cancer genomes. Exome sequences of 1,001 human cancer cell lines and 577 xenografts revealed most common mutational signatures, indicating past activity of the underlying processes, usually in appropriate cancer types. To investigate ongoing patterns of mutational-signature generation, cell lines were cultured for extended periods and subsequently DNA sequenced. Signatures of discontinued exposures, including tobacco smoke and ultraviolet light, were not generated in vitro. Signatures of normal and defective DNA repair and replication continued to be generated at roughly stable mutation rates. Signatures of APOBEC cytidine deaminase DNA-editing exhibited substantial fluctuations in mutation rate over time with episodic bursts of mutations. The initiating factors for the bursts are unclear, although retrotransposon mobilization may contribute. The examined cell lines constitute a resource of live experimental models of mutational processes, which potentially retain patterns of activity and regulation operative in primary human cancers.


Assuntos
Desaminases APOBEC/genética , Neoplasias/genética , Desaminases APOBEC/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , DNA/metabolismo , Análise Mutacional de DNA/métodos , Bases de Dados Genéticas , Exoma , Genoma Humano/genética , Xenoenxertos , Humanos , Mutagênese , Mutação/genética , Taxa de Mutação , Retroelementos , Sequenciamento do Exoma/métodos
2.
Glob Chang Biol ; 27(24): 6409-6422, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34465002

RESUMO

Land use and climate change are anticipated to affect phytoplankton of lakes worldwide. The effects will depend on the magnitude of projected land use and climate changes and lake sensitivity to these factors. We used random forests fit with long-term (1971-2016) phytoplankton and cyanobacteria abundance time series, climate observations (1971-2016), and upstream catchment land use (global Clumondo models for the year 2000) data from 14 European and 15 North American lakes basins. We projected future phytoplankton and cyanobacteria abundance in the 29 focal lake basins and 1567 lakes across focal regions based on three land use (sustainability, middle of the road, and regional rivalry) and two climate (RCP 2.6 and 8.5) scenarios to mid-21st century. On average, lakes are expected to have higher phytoplankton and cyanobacteria due to increases in both urban land use and temperature, and decreases in forest habitat. However, the relative importance of land use and climate effects varied substantially among regions and lakes. Accounting for land use and climate changes in a combined way based on extensive data allowed us to identify urbanization as the major driver of phytoplankton development in lakes located in urban areas, and climate as major driver in lakes located in remote areas where past and future land use changes were minimal. For approximately one-third of the studied lakes, both drivers were relatively important. The results of this large scale study suggest the best approaches for mitigating the effects of human activity on lake phytoplankton and cyanobacteria will depend strongly on lake sensitivity to long-term change and the magnitude of projected land use and climate changes at a given location. Our quantitative analyses suggest local management measures should focus on retaining nutrients in urban landscapes to prevent nutrient pollution from exacerbating ongoing changes to lake ecosystems from climate change.


Assuntos
Cianobactérias , Fitoplâncton , Mudança Climática , Ecossistema , Humanos , Lagos
3.
J Avian Med Surg ; 35(2): 217-226, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34256553

RESUMO

A 26-year-old, male eclectus parrot (Eclectus roratus) was presented to its primary care veterinarian for a 10-day history of increased respiratory effort, lethargy, and a single episode of regurgitation. Hepatomegaly, proventricular enlargement, cranial displacement of the ventriculus, and coelomic effusion were suspected based on a 1-view radiographic image, and the patient was referred for further evaluation. On presentation to the referral veterinary hospital, a distended coelom and dyspnea with abnormal respiratory sounds were abnormalities noted upon physical examination of the patient. The bird was hospitalized for supportive care, and diagnostic tests were performed. Initial radiographic images at the referral hospital revealed a large intracoelomic mass. A computed tomographic scan was performed; however, the origin of the mass could not be determined. A fine-needle aspirate and cytologic evaluation of the intracoelomic mass revealed a neoplastic process but no specific tissue type. Two days after presentation to the referral hospital, an exploratory coeliotomy to surgically resect the mass was attempted. The mass occupied most of the coelomic cavity, with multiple adhesions to internal organs. The mass was successfully resected; however, the patient destabilized and died despite resuscitation efforts. Histopathologic examination of submitted tissue from the mass with immunohistochemistry revealed mixed populations of neoplastic cells differentiated from 3 primordial germinal layers, confirming the diagnosis of teratoma. Teratomas appear to be a rare tumor in avian species but should be included in a list of differential disease diagnoses for abnormal tissue masses of unknown origin. Only 2 cases of teratomas have, to our knowledge, been reported in psittacine species.


Assuntos
Doenças das Aves , Papagaios , Teratoma , Animais , Doenças das Aves/diagnóstico por imagem , Diagnóstico Diferencial , Masculino , Teratoma/diagnóstico , Teratoma/veterinária
4.
Cytometry A ; 95(7): 797-802, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31034711

RESUMO

Shared resource laboratories (SRLs) offer instrumentation, training, and support to investigators and play an important role in the progress and development of science. To facilitate daily tasks and to provide an effective service, we have made use of computer scripts; a list of computer commands that are processed sequentially, to automate tasks in our flow cytometry facility. Using Python and an application programming interface (API), we automate user communication and produce a daily schedule display screen. We exploit the accessible nature of open standards to use R and Python to analyze and backup data from the BD Influx cell sorter. Finally, we show that through simple scripting, we can add value to an existing service by producing sort statistics from the Beckman Coulter XDP cell sorter. With these five examples, we demonstrate and wish to inspire other SRLs that the use of scripts helps to improve work efficiency, can solve problems, and can enhance the service provided by the SRL. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.


Assuntos
Citometria de Fluxo , Laboratórios , Citometria de Fluxo/normas , Laboratórios/normas , Software
5.
Cytometry A ; 95(3): 323-331, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30556955

RESUMO

The use of the DNA dyes Hoechst (HO) and chromomycin A3 (CA3) has become the preferred combination for the bivariate analysis of chromosomes from both human and animals. This analysis requires a flow cytometer equipped with lasers of specific wavelength and of higher power than is typical on a conventional bench top flow cytometer. In this study, we have investigated the resolution of chromosome peaks in a human cell line with normal flow karyotype using different combinations of DNA dyes on a number of flow cytometers available in a flow cytometry core facility. Chromosomes were prepared from the human cell line using a modified polyamine isolation buffer. The bivariate flow karyotypes of different DNA dyes combination; 4'-6-diamidino-2-phenylindole (DAPI) or Hoechst with propidium iodide (PI), obtained from different flow cytometers were compared to the reference flow karyotype of DAPI or Hoechst with chromomycin A3, generated from a Mo-Flo cell sorter using laser power settings of 300 mW each of UV and 457 nm. Good chromosome separation was observed in most of the flow cytometers used in the study. This study demonstrates that chromosome analysis and sorting can also be performed on benchtop flow cytometers equipped with the standard solid state 488 and 355 nm lasers, using a DNA dye combination of DAPI or Hoechst with PI. © 2018 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.


Assuntos
Cromossomos/química , DNA/análise , Citometria de Fluxo/métodos , Cariotipagem/métodos , Linhagem Celular , DNA/química , Fluorescência , Corantes Fluorescentes/química , Humanos , Lasers , Masculino , Propídio
6.
J Avian Med Surg ; 33(2): 150-154, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251502

RESUMO

A 10-year-old, female umbrella cockatoo (Cacatua alba) was presented for evaluation of a mass at the right commissure of the beak, with associated right periorbital swelling. A feather cyst was suspected, based on history and the results of a computed tomography scan and fine-needle aspirate. The cyst was surgically debrided and removed. Histopathologic results confirmed an infraorbital keratin cyst, most likely originating from a feather follicle. To our knowledge, this is the first reported case of a periorbital keratin cyst in a bird.


Assuntos
Doenças das Aves/diagnóstico , Cacatuas , Cistos/veterinária , Animais , Doenças das Aves/patologia , Cistos/patologia , Cistos/cirurgia , Feminino
7.
Appl Environ Microbiol ; 82(17): 5410-20, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27342564

RESUMO

UNLABELLED: While commonplace in clinical settings, DNA-based assays for identification or enumeration of drinking water pathogens and other biological contaminants remain widely unadopted by the monitoring community. In this study, shotgun metagenomics was used to identify taste-and-odor producers and toxin-producing cyanobacteria over a 2-year period in a drinking water reservoir. The sequencing data implicated several cyanobacteria, including Anabaena spp., Microcystis spp., and an unresolved member of the order Oscillatoriales as the likely principal producers of geosmin, microcystin, and 2-methylisoborneol (MIB), respectively. To further demonstrate this, quantitative PCR (qPCR) assays targeting geosmin-producing Anabaena and microcystin-producing Microcystis were utilized, and these data were fitted using generalized linear models and compared with routine monitoring data, including microscopic cell counts, sonde-based physicochemical analyses, and assays of all inorganic and organic nitrogen and phosphorus forms and fractions. The qPCR assays explained the greatest variation in observed geosmin (adjusted R(2) = 0.71) and microcystin (adjusted R(2) = 0.84) concentrations over the study period, highlighting their potential for routine monitoring applications. The origin of the monoterpene cyclase required for MIB biosynthesis was putatively linked to a periphytic cyanobacterial mat attached to the concrete drinking water inflow structure. We conclude that shotgun metagenomics can be used to identify microbial agents involved in water quality deterioration and to guide PCR assay selection or design for routine monitoring purposes. Finally, we offer estimates of microbial diversity and metagenomic coverage of our data sets for reference to others wishing to apply shotgun metagenomics to other lacustrine systems. IMPORTANCE: Cyanobacterial toxins and microbial taste-and-odor compounds are a growing concern for drinking water utilities reliant upon surface water resources. Specific identification of the microorganism(s) responsible for water quality degradation is often complicated by the presence of co-occurring taxa capable of producing these undesirable metabolites. Here we present a framework for how shotgun metagenomics can be used to definitively identify problematic microorganisms and how these data can guide the development of rapid genetic assays for routine monitoring purposes.


Assuntos
Bactérias/isolamento & purificação , Cianobactérias/isolamento & purificação , Água Potável/química , Água Potável/microbiologia , Água Doce/química , Água Doce/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Cianobactérias/classificação , Cianobactérias/genética , Cianobactérias/metabolismo , Humanos , Metagenômica , Odorantes/análise , Paladar , Abastecimento de Água
8.
J Pathol ; 237(3): 296-306, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26096211

RESUMO

The study of the relationships between pre-cancer and cancer and identification of early driver mutations is becoming increasingly important as the value of molecular markers of early disease and personalised drug targets is recognized, especially now the extent of clonal heterogeneity in fully invasive disease is being realized. It has been assumed that pre-cancerous lesions exhibit a fairly passive progression to invasive disease; the degree to which they, too, are heterogeneous is unknown. We performed ultra-deep sequencing of thousands of selected mutations, together with copy number analysis, from multiple, matched pre-invasive lesions, primary tumours and metastases from five patients with oral cancer, some with multiple primary tumours presenting either synchronously or metachronously, totalling 75 samples. This allowed the clonal relationships between the samples to be observed for each patient. We expose for the first time the unexpected variety and complexity of the relationships between this group of oral dysplasias and their associated carcinomas and, ultimately, the diversity of processes by which tumours are initiated, spread and metastasize. Instead of a series of genomic precursors of their adjacent invasive disease, we have shown dysplasia to be a distinct dynamic entity, refuting the belief that pre-cancer and invasive tumours with a close spatial relationship always have linearly related genomes. We show that oral pre-cancer exhibits considerable subclonal heterogeneity in its own right, that mutational changes in pre-cancer do not predict the onset of invasion, and that the genomic pathway to invasion is neither unified nor predictable. Sequence data from this study have been deposited in the European Nucleotide Archive, Accession No. PRJEB6588.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/genética , Linhagem da Célula , Transformação Celular Neoplásica/genética , Evolução Clonal , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Bucais/genética , Lesões Pré-Cancerosas/genética , Análise de Sequência de DNA/métodos , Carcinoma/secundário , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica/patologia , Progressão da Doença , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Neoplasias Bucais/patologia , Mutação , Invasividade Neoplásica , Fenótipo , Lesões Pré-Cancerosas/patologia
9.
J Zoo Wildl Med ; 47(1): 379-82, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27010308

RESUMO

Macropods are susceptible to trauma, and fractures of the cervical vertebrae due to collisions are relatively common. A 4-yr-old, intact male Bennett's wallaby (Macropus rufogriseus) was presented acutely nonambulatory and tetraparetic but with motor function present in all limbs. Cervical radiographs revealed a C4 vertebral fracture. Surgical stabilization was obtained through a ventral midline approach whereby the vertebral bodies were distracted and then secured with screws and polymethylmethacrylate (PMMA). Postoperative radiographs revealed restoration of the spinal canal and appropriate implant placement. The patient was discharged 4 days postoperatively and gradually recovered full neurologic function per the owner over the ensuing 10 wk. Subsequent radiographs obtained 10.5 mo postoperatively revealed a healed fracture with stable implants. The ventral spinal distraction and stabilization technique using screws and PMMA, as are used in the domestic dog, was successful in this wallaby despite its smaller vertebral size and comparable lack of soft-tissue support.


Assuntos
Vértebras Cervicais/cirurgia , Fixação Interna de Fraturas/veterinária , Macropodidae , Fraturas da Coluna Vertebral/veterinária , Animais , Vértebras Cervicais/patologia , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/patologia
10.
Sci Total Environ ; 954: 175067, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39111421

RESUMO

Phytoplankton overgrowth, which characterizes the eutrophication or trophic status of surface water bodies, threatens ecosystems and public health. Quantitative polymerase chain reaction (qPCR) is promising for assessing the abundance and community composition of phytoplankton. However, applications of qPCR to indicate eutrophication and trophic status, especially in lotic systems, have yet to be comprehensively evaluated. For the first time, this study correlates qPCR-based phytoplankton abundance with chlorophyll a (the most widely used indicator of eutrophication and trophic status) in multiple freshwater rivers. From early summer to late fall in 2017, 2018, and 2019, we evaluated phytoplankton, chlorophyll a, pheophytin a, and the Trophic Level Index (TLI) in twelve large freshwater rivers in three regions (western, midcontinent, and eastern) in the United States. Chlorophyll a concentration had positive allometric correlations with qPCR-based phytoplankton abundance (adjusted R2 = 0.5437, p-value < 0.001), pheophytin a concentration (adjusted R2 = 0.3378, p-value <0.001), and TLI (adjusted R2 = 0.4789, p-value < 0.001). Thus, a greater phytoplankton abundance suggests a higher trophic status. This work also presents the numerical values of qPCR-based phytoplankton abundance defining the boundaries among trophic statuses (e.g., oligotrophic, mesotrophic, and eutrophic) of freshwater rivers. The sampling sites in the midcontinent rivers were more eutrophic because they had significantly higher chlorophyll a concentrations, pheophytin a concentrations, and TLI values than the sites in the western and eastern rivers. The higher phytoplankton abundance at the midcontinent sites confirmed their higher trophic status. By linking qPCR-based phytoplankton abundance to chlorophyll a, this study demonstrates that qPCR is a promising avenue to investigate the population dynamics of phytoplankton and the trophic status (or eutrophication) of freshwater rivers.

11.
Am J Vet Res ; 85(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325002

RESUMO

OBJECTIVE: This study aimed to characterize the bacterial and eukaryotic microbiota of the gastrointestinal (GI) tract in domestic rabbits and to evaluate the effect of different diet characteristics, such as pelleting, extrusion, and hay supplementation. ANIMALS: 30 New Zealand White rabbits (15 male and 15 female; 6 to 7 months old) were fed 1 of 6 diets (5 rabbits per diet) for 30 days after an initial acclimation period. At the end of the trial, samples were collected from the stomach, small intestine, cecum, large intestine, and hard feces. METHODS: The samples were analyzed using 16S rRNA and internal transcribed spacer 1 region-targeted amplicon sequencing. RESULTS: The bacterial microbiota was distinct between the foregut and hindgut. The most abundant bacterial genera included an unclassified genus in the Bacteroidales order and Alistipes. Candida was the most abundant genus in the eukaryotic dataset. In the bacterial dataset, diet No Hay/Pellet E was shown to have lower diversity (Shannon diversity, P < .05) compared to all diet groups except for No Hay/Pellet M. Few significant differences in alpha-diversity indexes between diet groups were detected in the eukaryotic dataset. CLINICAL RELEVANCE: Our findings demonstrated that feeding hay had a significant effect on the beta diversity of the bacterial microbiota. Given the prevalence of gastrointestinal disease in the domestic rabbit population, furthering our understanding of what constitutes a healthy rabbit microbiota and the effects of different diets on the microbial community can help veterinarians implement better intervention strategies and allow pet owners to provide the best level of care.


Assuntos
Trato Gastrointestinal , Microbiota , Coelhos , Animais , Feminino , Masculino , RNA Ribossômico 16S/genética , Dieta/veterinária , Ceco , Bactérias/genética , Ração Animal/análise , Fezes/microbiologia
12.
Adv Health Sci Educ Theory Pract ; 18(5): 975-85, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23283572

RESUMO

"Curricula-in-action" generally differ from "official" curricula. That is particularly true of clerkship curricula because the practising doctors who supervise medical students' clinical activities are only secondarily educators. Clerkship education is evaluated, however, according to benchmarks set by official curricula. As a result, clerkship evaluations are important points of contact between clinical teachers and medical schools. We reasoned that an evaluation instrument is part of a medical school's official curriculum discourse and clinical teachers' reactions to it are a discourse of curriculum-in-action. We set out to answer the questions: What are clinical teachers' discourses of curriculum-in-action and how do they relate to an official curriculum discourse? Nineteen clerkship placement leads from two hospitals contributing to a single undergraduate medical programme participated. The evaluation instrument was the Manchester Clinical Placement Index, for which validity evidence has been published. Respondents were asked to say how they would react to junior students giving their placements low or high scores for each of 12 items from the Index. After transcription, we conducted a critical discourse analysis (CDA) of their audio-recorded answers. We purposefully selected the six items that elicited the widest spectrum of responses for analysis because quantity of material can compromise the quality of CDA. A dominant discourse of curriculum-in-action defined how teachers should "really" teach and junior students should learn. It deconstructed the need for teachers to be present when students performed clinical tasks because teachers' role was to give critical feedback on case presentations that were coincidental to clinical care. It positioned students at the bottom of a power hierarchy so they had to "struggle" to be taught. It placed respondents in a powerful position relative to "the hospital" and "the university", though there were tensions between respondents, patients, and nurses. Respondents dismissed criticism that was invalid according to their curriculum-in-action, which included most items in an evaluation instrument. There was a contrasting, non-dominant discourse of responding reflectively to feedback, which generated realistic ways of improving students' learning. The strength of respondents' emotions shows just how committed doctors are to students' learning. The strength of their expressions of power, however, explains why many of them teach in their own way rather than according to official curricula. Changes to clinical curricula, our findings suggest, will not be successful unless they are carefully negotiated with practising doctors.


Assuntos
Estágio Clínico , Currículo , Educação de Graduação em Medicina/métodos , Aprendizagem Baseada em Problemas , Estudantes de Medicina/psicologia , Inglaterra , Retroalimentação , Feminino , Humanos , Masculino
13.
J Public Health Manag Pract ; 19(5): 468-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23266755

RESUMO

State and local health departments (LHDs) are increasingly conducting community health assessments, using models such as Mobilizing for Action through Planning and Partnerships. Within the peer-reviewed literature, relevant Web sites, and textbooks on health planning, there is limited practical guidance for bridging data collection and prioritization. The purpose of this article was to provide examples of how LHDs have bridged these steps through "data synthesis." We provide examples from 3 LHDs that have extensive experience with the Mobilizing for Action through Planning and Partnerships model. The LHDs provide a detailed synopsis of data synthesis activities, including the setting, participants, processes, and outcomes. Commonalities between the LHDs' processes emerged, including daylong (or more) retreats, multiple nominal group-like techniques, and iterative approaches to reduce the number of strategic issues. These processes provide examples of data synthesis and are relevant to current practice, given the national voluntary accreditation process and the new nonprofit hospital requirements to conduct community health assessments.


Assuntos
Gestão da Informação em Saúde , Vigilância da População , Planejamento em Saúde , Kentucky , Governo Local , Modelos Organizacionais , Saúde Pública , Estados Unidos
14.
Sci Rep ; 13(1): 2806, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797305

RESUMO

Cyanobacteria and cyanotoxin producing cyanobacterial blooms are a trending focus of current research. Many studies focus on bloom events in lentic environments such as lakes or ponds. Comparatively few studies have explored lotic environments and fewer still have examined the cyanobacterial communities and potential cyanotoxin producers during ambient, non-bloom conditions. Here we used a metagenomics-based approach to profile non-bloom microbial communities and cyanobacteria in 12 major U.S. rivers at multiple time points during the summer months of 2019. Our data show that U.S. rivers possess microbial communities that are taxonomically rich, yet largely consistent across geographic location and time. Within these communities, cyanobacteria often comprise significant portions and frequently include multiple species with known cyanotoxin producing strains. We further characterized these potential cyanotoxin producing taxa by deep sequencing amplicons of the microcystin E (mcyE) gene. We found that rivers containing the highest levels of potential cyanotoxin producing cyanobacteria consistently possess taxa with the genetic potential for cyanotoxin production and that, among these taxa, the predominant genus of origin for the mcyE gene is Microcystis. Combined, these data provide a unique perspective on cyanobacteria and potential cyanotoxin producing taxa that exist in large rivers across the U.S. and can be used to better understand the ambient conditions that may precede bloom events in lotic freshwater ecosystems.


Assuntos
Cianobactérias , Microbiota , Microcystis , Estados Unidos , Cianobactérias/genética , Rios/microbiologia , Lagos/microbiologia , Microcistinas/genética
15.
Water Res ; 235: 119679, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37011576

RESUMO

Phytoplankton is the essential primary producer in fresh surface water ecosystems. However, excessive phytoplankton growth due to eutrophication significantly threatens ecologic, economic, and public health. Therefore, phytoplankton identification and quantification are essential to understanding the productivity and health of freshwater ecosystems as well as the impacts of phytoplankton overgrowth (such as Cyanobacterial blooms) on public health. Microscopy is the gold standard for phytoplankton assessment but is time-consuming, has low throughput, and requires rich experience in phytoplankton morphology. Quantitative polymerase chain reaction (qPCR) is accurate and straightforward with high throughput. In addition, qPCR does not require expertise in phytoplankton morphology. Therefore, qPCR can be a useful alternative for molecular identification and enumeration of phytoplankton. Nonetheless, a comprehensive study is missing which evaluates and compares the feasibility of using qPCR and microscopy to assess phytoplankton in fresh water. This study 1) compared the performance of qPCR and microscopy in identifying and quantifying phytoplankton and 2) evaluated qPCR as a molecular tool to assess phytoplankton and indicate eutrophication. We assessed phytoplankton using both qPCR and microscopy in twelve large freshwater rivers across the United States from early summer to late fall in 2017, 2018, and 2019. qPCR- and microscope-based phytoplankton abundance had a significant positive linear correlation (adjusted R2 = 0.836, p-value < 0.001). Phytoplankton abundance had limited temporal variation within each sampling season and over the three years studied. The sampling sites in the midcontinent rivers had higher phytoplankton abundance than those in the eastern and western rivers. For instance, the concentration (geometric mean) of Bacillariophyta, Cyanobacteria, Chlorophyta, and Dinoflagellates at the sampling sites in the midcontinent rivers was approximately three times that at the sampling sites in the western rivers and approximately 18 times that at the sampling sites in the eastern rivers. Welch's analysis of variance indicates that phytoplankton abundance at the sampling sites in the midcontinent rivers was significantly higher than that at the sampling sites in the eastern rivers (p-value = 0.013) but was comparable to that at the sampling sites in the western rivers (p-value = 0.095). The higher phytoplankton abundance at the sampling sites in the midcontinent rivers was presumably because these rivers were more eutrophic. Indeed, low phytoplankton abundance occurred in oligotrophic or low trophic sites, whereas eutrophic sites had greater phytoplankton abundance. This study demonstrates that qPCR-based phytoplankton abundance can be a useful numerical indicator of the trophic conditions and water quality in freshwater rivers.


Assuntos
Cianobactérias , Fitoplâncton , Estados Unidos , Ecossistema , Cianobactérias/genética , Rios , Água Doce/microbiologia , Eutrofização , Estações do Ano , China
16.
Adv Health Sci Educ Theory Pract ; 17(5): 703-16, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22234383

RESUMO

The drive to quality-manage medical education has created a need for valid measurement instruments. Validity evidence includes the theoretical and contextual origin of items, choice of response processes, internal structure, and interrelationship of a measure's variables. This research set out to explore the validity and potential utility of an 11-item measurement instrument, whose theoretical and empirical origins were in an Experience Based Learning model of how medical students learn in communities of practice (COPs), and whose contextual origins were in a community-oriented, horizontally integrated, undergraduate medical programme. The objectives were to examine the psychometric properties of the scale in both hospital and community COPs and provide validity evidence to support using it to measure the quality of placements. The instrument was administered twice to students learning in both hospital and community placements and analysed using exploratory factor analysis and a generalizability analysis. 754 of a possible 902 questionnaires were returned (84% response rate), representing 168 placements. Eight items loaded onto two factors, which accounted for 78% of variance in the hospital data and 82% of variance in the community data. One factor was the placement learning environment, whose five constituent items were how learners were received at the start of the placement, people's supportiveness, and the quality of organisation, leadership, and facilities. The other factor represented the quality of training-instruction in skills, observing students performing skills, and providing students with feedback. Alpha coefficients ranged between 0.89 and 0.93 and there were no redundant or ambiguous items. Generalisability analysis showed that between 7 and 11 raters would be needed to achieve acceptable reliability. There is validity evidence to support using the simple 8-item, mixed methods Manchester Clinical Placement Index to measure key conditions for undergraduate medical students' experience based learning: the quality of the learning environment and the training provided within it. Its conceptual orientation is towards Communities of Practice, which is a dominant contemporary theory in undergraduate medical education.


Assuntos
Estágio Clínico , Aprendizagem , Estudantes de Medicina , Estágio Clínico/organização & administração , Estágio Clínico/normas , Educação de Graduação em Medicina , Inglaterra , Análise Fatorial , Humanos , Inquéritos e Questionários
18.
Am J Vet Res ; 83(4): 371-380, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35092668

RESUMO

OBJECTIVE: To determine hepatic copper concentrations and zonal distribution in ferrets with and without hepatobiliary disease, validate rhodanine-based qualitative copper scoring and digital copper quantification in ferret hepatic samples, and ascertain whether clinical features predicted copper accumulation. ANIMALS: 34 ferrets, including 7 with necroinflammatory disease, 5 with hepatocellular carcinoma, 13 with non-necroinflammatory disease, and 9 with no hepatobiliary disease. PROCEDURES: Rhodanine-based digital copper quantification was validated by use of liver dually measured by atomic absorption spectroscopy and digital scanning (R2 = 0.98). Clinical features and hepatic copper scores and concentrations (dry weight liver) were compared between groups. Zonal copper distribution was determined. RESULTS: Hepatic copper concentration was strongly correlated with copper scores (ρ = 0.88). Ferrets with hepatobiliary disease were significantly older and had significantly higher serum alkaline phosphatase and γ-glutamyltransferase activities and creatinine concentrations. Centrilobular copper accumulated in 23 of 34 (64%) ferrets with (n = 15) and without (8) hepatobiliary disease. Median copper concentrations were not significantly different between ferrets with and without hepatobiliary disease but were significantly higher within neoplastic hepatic tissue in ferrets with hepatocellular carcinoma. Hepatic copper concentrations exceeded feline (> 180 µg/g) and canine (> 400 µg/g) reference limits in 19 and 9 ferrets, respectively. Hepatic copper > 1,000 µg/g occurred in 5 ferrets with and 2 without hepatobiliary disease. Clinical features did not predict copper accumulation. CLINICAL RELEVANCE: Rhodanine-based digital copper quantification and qualitative copper scoring discerned liver copper accumulation in ferrets. Ferrets with and without hepatobiliary disease displayed a propensity for centrilobular hepatic copper accumulation of uncertain clinical importance. Clinical and clinicopathologic features could not exclusively implicate pathologic copper accumulation.


Assuntos
Doenças do Gato , Doenças do Sistema Digestório , Doenças do Cão , Rodanina , Animais , Gatos , Cobre/análise , Doenças do Sistema Digestório/veterinária , Cães , Furões , Fígado/química , Rodanina/análise
19.
BMJ Open ; 12(11): e065429, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414283

RESUMO

INTRODUCTION: While there have been several literature reviews on the performance of digital sepsis prediction technologies and clinical decision-support algorithms for adults, there remains a knowledge gap in examining the development of automated technologies for sepsis prediction in children. This scoping review will critically analyse the current evidence on the design and performance of automated digital technologies to predict paediatric sepsis, to advance their development and integration within clinical settings. METHODS AND ANALYSIS: This scoping review will follow Arksey and O'Malley's framework, conducted between February and December 2022. We will further develop the protocol using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. We plan to search the following databases: Association of Computing Machinery (ACM) Digital Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Google Scholar, Institute of Electric and Electronic Engineers (IEEE), PubMed, Scopus and Web of Science. Studies will be included on children >90 days postnatal to <21 years old, predicted to have or be at risk of developing sepsis by a digitalised model or algorithm designed for a clinical setting. Two independent reviewers will complete the abstract and full-text screening and the data extraction. Thematic analysis will be used to develop overarching concepts and present the narrative findings with quantitative results and descriptive statistics displayed in data tables. ETHICS AND DISSEMINATION: Ethics approval for this scoping review study of the available literature is not required. We anticipate that the scoping review will identify the current evidence and design characteristics of digital prediction technologies for the timely and accurate prediction of paediatric sepsis and factors influencing clinical integration. We plan to disseminate the preliminary findings from this review at national and international research conferences in global and digital health, gathering critical feedback from multidisciplinary stakeholders. SCOPING REVIEW REGISTRATION: https://osf.io/veqha/?view_only=f560d4892d7c459ea4cff6dcdfacb086.


Assuntos
Tecnologia Digital , Sepse , Adulto , Criança , Humanos , Recém-Nascido , Programas de Rastreamento , Sepse/diagnóstico , Revisões Sistemáticas como Assunto , Literatura de Revisão como Assunto
20.
J Cardiovasc Dev Dis ; 10(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36661906

RESUMO

People living with CHD do less moderate-to-vigorous activity than their peers. This study sought to examine the impact of a community-based physical activity intervention for individuals with CHD. Individuals with CHD and family members participated in a 3 h, one-day Fearless event consisting of a variety of physical activity and education sessions. Consenting participants completed self-administered questionnaires pre-/post-event and completed a post-event feedback form. Descriptive statistics and paired t-tests were calculated across subgroups for each outcome/questionnaire. Written feedback was analyzed using a six-phase framework of reflexive thematic analysis. A total of 32 participants (six children, six adolescents, five youth, five all ages, and ten adults) with CHD completed this study. Following Fearless, youth with CHD reported spending less time being 'inactive' and more time being 'somewhat active'. Adults with CHD reported spending more time walking and partaking in moderate activity and less time partaking in vigorous activity. Fearless successfully engaged individuals with CHD who were more sedentary, less active, and older. Fearless is a fun, family-friendly, physical activity intervention for individuals with CHD. Attending a Fearless event helped children, adolescents, and adults with CHD make incremental improvements to their physical activity levels and provided a framework for sport and recreation leaders who aim to promote physical activity amongst individuals with CHD.

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