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1.
Ecol Evol ; 11(21): 15325-15350, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765181

RESUMO

The shell morphologies of the freshwater mussel species Pleurobema clava (federally endangered) and Pleurobema oviforme (species of concern) are similar, causing considerable taxonomic confusion between the two species over the last 100 years. While P. clava was historically widespread throughout the Ohio River basin and tributaries to the lower Laurentian Great Lakes, P. oviforme was confined to the Tennessee and the upper Cumberland River basins. We used two mitochondrial DNA (mtDNA) genes, 13 novel nuclear DNA microsatellite markers, and shell morphometrics to help resolve this taxonomic confusion. Evidence for a single species was apparent in phylogenetic analyses of each mtDNA gene, revealing monophyletic relationships with minimal differentiation and shared haplotypes. Analyses of microsatellites showed significant genetic structuring, with four main genetic clusters detected, respectively, in the upper Ohio River basin, the lower Ohio River and Great Lakes, and upper Tennessee River basin, and a fourth genetic cluster, which included geographically intermediate populations in the Ohio and Tennessee river basins. While principal components analysis (PCA) of morphometric variables (i.e., length, height, width, and weight) showed significant differences in shell shape, only 3% of the variance in shell shape was explained by nominal species. Using Linear Discriminant and Random Forest (RF) analyses, correct classification rates for the two species' shell forms were 65.5% and 83.2%, respectively. Random Forest classification rates for some populations were higher; for example, for North Fork Holston (HOLS), it was >90%. While nuclear DNA and shell morphology indicate that the HOLS population is strongly differentiated, perhaps indicative of cryptic biodiversity, we consider the presence of a single widespread species the most likely biological scenario for many of the investigated populations based on our mtDNA dataset. However, additional sampling of P. oviforme populations at nuclear loci is needed to corroborate this finding.

2.
Clin Toxicol (Phila) ; 56(8): 773-781, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29334816

RESUMO

BACKGROUND: Colchicine poisoning is commonly lethal. Colchicine-specific Fab fragments increase rat urinary colchicine clearance and have been associated with a good outcome in one patient. We aimed to develop a porcine model of colchicine toxicity to study the pharmacokinetics and efficacy of ovine Fab. METHODS: A Göttingen minipig critical care model was established and serial blood samples taken for colchicine and Fab pharmacokinetics, clinical chemistry, and haematology. Animals were euthanised when the mean arterial pressure fell below 45 mmHg without response to vasopressor, or at study completion. RESULTS: Initial studies indicated that oral dosing produced variable pharmacokinetics and time-to-euthanasia. By contrast, intravenous infusion of 0.25 mg/kg colchicine over 1 h produced reproducible pharmacokinetics (AUC0-20 343 [SD = 21] µg/L/h), acute multi-organ injury, and cardiotoxicity requiring euthanasia a mean of 22.5 (SD = 3.2) h after dosing. A full-neutralising equimolar Fab dose given 6 h after the infusion (50% first hour, 50% next 6 h [to reduce renal-loss of unbound Fab]) produced a 7.35-fold increase in plasma colchicine (AUC0-20 2,522 [SD = 14] µg/L/h), and removed all free plasma colchicine, but did not prevent toxicity (euthanasia at 29.1 [SD = 3.4] h). Earlier administration over 1 h of the full-neutralising dose, 1 or 3 h after the colchicine, produced a 12.9-fold (AUC0-20 4,433 [SD = 607] µg/L/h) and 6.0-fold (AUC0-20 2,047 [SD = 51] µg/L/h) increase in plasma colchicine, respectively, absence of free plasma colchicine until 20 h, and survival to study end without marked cardiotoxicity. CONCLUSIONS: Colchicine-specific Fab given early, in equimolar dose, bound colchicine, eliciting its movement into the blood, and preventing severe toxicity. Clinical studies are now needed to determine how soon this antidote must be given to work in human poisoning.


Assuntos
Antídotos/farmacologia , Antídotos/uso terapêutico , Colchicina/sangue , Colchicina/intoxicação , Fragmentos Fab das Imunoglobulinas/farmacologia , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Administração Intravenosa , Administração Oral , Animais , Fragmentos Fab das Imunoglobulinas/sangue , Modelos Animais , Suínos , Porco Miniatura
3.
Lancet Gastroenterol Hepatol ; 2(7): 479-493, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28506538

RESUMO

BACKGROUND: A gluten-free diet is the only means to manage coeliac disease, a permanent immune intolerance to gluten. We developed a therapeutic vaccine, Nexvax2, designed to treat coeliac disease. Nexvax2 is an adjuvant-free mix of three peptides that include immunodominant epitopes for gluten-specific CD4-positive T cells. The vaccine is intended to engage and render gluten-specific CD4-positive T cells unresponsive to further antigenic stimulation. We assessed the safety and pharmacodynamics of the vaccine in patients with coeliac disease on a gluten-free diet. METHODS: We did two randomised, double-blind, placebo-controlled, phase 1 studies at 12 community sites in Australia, New Zealand, and the USA, in HLA-DQ2·5-positive patients aged 18-70 years who had coeliac disease and were on a gluten-free diet. In the screening period for ascending dose cohorts, participants were randomly assigned (1:1) by central randomisation with a simple block method to a double-blind crossover, placebo-controlled oral gluten challenge. Participants with a negative interferon γ release assay to Nexvax2 peptides after the screening oral gluten challenge were discontinued before dosing. For the biopsy cohorts, the screening period included an endoscopy, and participants with duodenal histology who had a Marsh score of greater than 1 were discontinued before dosing. Participants were subsequently randomly assigned to either Nexvax2 or placebo in ascending dose cohorts (2:1) and in biopsy cohorts (1:1) by central randomisation with a simple block method. In the three-dose study, participants received either Nexvax2 60 µg, 90 µg, or 150 µg weekly, or placebo over 15 days; in a fourth biopsy cohort, patients received either Nexvax2 at the maximum tolerated dose (MTD) or placebo. In the 16-dose study, participants received Nexvax2 150 µg or 300 µg or placebo twice weekly over 53 days; in a third biopsy cohort, patients also received either Nexvax2 at the MTD or placebo. In the 4-week post-treatment period, ascending dose cohorts underwent a further double-blind crossover, placebo-controlled oral gluten challenge, which had a fixed sequence, and biopsy cohorts had a gastroscopy with duodenal biopsies and quantitative histology within 2 weeks without oral gluten challenge. Participants, investigators, and study staff were masked to the treatment assignment, except for the study pharmacist. The primary endpoint was the number and percentage of adverse events in the treatment period in an intention-to-treat analysis. Both trials were completed and closed before data analysis. Trials were registered with the Australian New Zealand Clinical Trials Registry, numbers ACTRN12612000355875 and ACTRN12613001331729. FINDINGS: Participants were enrolled from Nov 28, 2012, to Aug 14, 2014, in the three-dose study, and from Aug 3, 2012, to Sept 10, 2013, in the 16-dose study. Overall, 62 (57%) of 108 participants were randomly assigned after oral gluten challenge and 20 (71%) of 28 participants were randomly assigned after endoscopy. In the three-dose study, nine participants were randomly allocated to Nexvax2 60 µg and three to placebo (first cohort), nine were allocated to Nexvax2 90 µg and four to placebo (second cohort), eight were allocated to Nexvax2 150 µg and four to placebo (third cohort), and three were allocated to Nexvax2 150 µg and three to placebo (biopsy cohort). In the 16-dose study, eight participants were randomly allocated to Nexvax2 150 µg and four to placebo (first cohort), ten were allocated to Nexvax2 300 µg and three to placebo (second cohort), and seven were allocated to Nexvax2 150 µg and seven to placebo (biopsy cohort). The MTD for Nexvax2 was 150 µg because of transient, acute gastrointestinal adverse events with onset 2-5 h after initial doses of the vaccine, similar to those caused by gluten ingestion. In the ascending dose cohorts in the three-dose study, six (55%) of 11 placebo recipients, five (56%) of nine who received Nexvax2 60 µg, seven (78%) of nine who received Nexvax2 90 µg, and five (63%) of eight who received Nexvax2 150 µg had at least one treatment-emergent adverse event, as did all three (100%) placebo recipients and one (33%) of three Nexvax2 150 µg recipients in the biopsy cohort. In the ascending dose cohorts of the 16-dose study, five (71%) of seven placebo-treated participants, six (75%) of eight who received Nexvax2 150 µg, and all ten (100%) who received Nexvax2 300 µg had at least one treatment-emergent adverse event, as did six (86%) of seven placebo recipients and five (71%) of seven Nexvax2 150 µg recipients in the biopsy cohort. Vomiting, nausea, and headache were the only treatment-emergent adverse events that occurred in at least 5% of participants in either study. Among participants given the MTD, eight gastrointestinal treatment-emergent adverse events occurred in four (50%) of eight participants in the third cohort and none (0%) of three participants in the biopsy cohort in the three-dose study, and five events occurred in five (63%) of eight participants in the first cohort and three events in two (29%) of seven participants in the biopsy cohort of the 16-dose study. Median villous height to crypt depth ratio in distal duodenal biopsies was not significantly different between those who received the vaccine at the MTD on either schedule and those who received placebo. Of the participants who completed the post-treatment oral gluten challenge per protocol, interferon γ release assay to Nexvax2 peptides was negative (responders to treatment) in two (22%) of nine placebo-treated participants in the three-dose study versus two (33%) of six who received Nexvax2 60 µg, five (63%) of eight who received Nexvax2 90 µg, and six (100%) of six who received Nexvax2 150 µg (p=0·007); in the 16-dose study, none (0%) of five placebo-treated participants had a negative assay versus six (75%) of eight who received Nexvax2 150 µg (p=0·021). INTERPRETATION: The MTD of Nexvax2 was 150 µg for twice weekly intradermal administration over 8 weeks, which modified immune responsiveness to Nexvax2 peptides without deterioration in duodenal histology. The gastrointestinal symptoms that followed the first intradermal administration of the vaccine resembled those associated with oral gluten challenge. These findings support continued clinical development of this potential therapeutic vaccine for coeliac disease. FUNDING: ImmusanT.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Doença Celíaca/terapia , Epitopos/imunologia , Oligopeptídeos/administração & dosagem , Vacinas/administração & dosagem , Adolescente , Adulto , Idoso , Biópsia , Doença Celíaca/patologia , Estudos Cross-Over , Dieta Livre de Glúten , Método Duplo-Cego , Esquema de Medicação , Duodeno/patologia , Feminino , Gastroenteropatias/etiologia , Humanos , Injeções Intradérmicas , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Oligopeptídeos/efeitos adversos , Oligopeptídeos/imunologia , Vacinas/efeitos adversos , Vacinas/imunologia , Adulto Jovem
4.
Mitochondrial DNA B Resour ; 1(1): 954-957, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33473690

RESUMO

We have sequenced the female and male mtDNA of Unio delphinus and inferred the Unionidae phylogeny using 41 complete mtDNA sequences. Additionally, we compared the concatenated mtDNA trees with those using single or combination of two mtDNA genes to identify the best genes to use in the absence of complete mitogenomes. The gender-specific mtDNAs of U. delphinus contain all Unionida mtDNA specific features. The mtDNA phylogeny supports the reciprocal monophyly of the gender-specific clades but it was inconclusive regarding Unionidae subfamilies relationships. The gene trees topologies using ND5 or 16S-rRNA with ND1 were the closest trees to the mtDNA trees.

5.
Sci Rep ; 6: 21645, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26898342

RESUMO

We describe a fundamentally novel feat of animal genetic engineering: the precise and efficient substitution of an agronomic haplotype into a domesticated species. Zinc finger nuclease in-embryo editing of the RELA locus generated live born domestic pigs with the warthog RELA orthologue, associated with resilience to African Swine Fever. The ability to efficiently achieve interspecies allele introgression in one generation opens unprecedented opportunities for agriculture and basic research.


Assuntos
Resistência à Doença/genética , Edição de Genes/métodos , Engenharia Genética , Ligases/genética , Febre Suína Africana/genética , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/patogenicidade , Alelos , Animais , Genoma , Haplótipos , Suínos
6.
PLoS One ; 11(1): e0146295, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26730588

RESUMO

A fundamental issue in the management and conservation of biodiversity is how to define a population. Spatially contiguous fish occupying a stream network have often been considered to represent a single, homogenous population. However, they may also represent multiple discrete populations, a single population with genetic isolation-by-distance, or a metapopulation. We used microsatellite DNA and a large-scale mark-recapture study to assess population structure in a spatially contiguous sample of Brook Trout (Salvelinus fontinalis), a species of conservation concern. We found evidence for limited genetic exchange across small spatial scales and in the absence of barriers to physical movement. Mark-recapture and stationary passive integrated transponder antenna records demonstrated that fish from two tributaries very seldom moved into the opposite tributary, but movements between the tributaries and mainstem were more common. Using Bayesian genetic clustering, we identified two genetic groups that exhibited significantly different growth rates over three years of study, yet survival rates were very similar. Our study highlights the importance of considering the possibility of multiple genetically distinct populations occurring within spatially contiguous habitats, and suggests the existence of a cryptic metapopulation: a spatially continuous distribution of organisms exhibiting metapopulation-like behaviors.


Assuntos
Conservação dos Recursos Naturais/métodos , Pesqueiros/métodos , Repetições de Microssatélites/genética , Truta/genética , Animais , Teorema de Bayes , Análise por Conglomerados , Ecossistema , Frequência do Gene , Variação Genética , Genética Populacional , Genótipo , Geografia , Desequilíbrio de Ligação , Maryland , Dinâmica Populacional , Rios , Truta/classificação , Truta/fisiologia
7.
Mol Ecol ; 24(23): 5864-76, 2015 12.
Artigo em Inglês | MEDLINE | ID: mdl-26518618

RESUMO

There is widespread concern regarding the impacts of anthropogenic activities on connectivity among populations of plants and animals, and understanding how contemporary and historical processes shape metapopulation dynamics is crucial for setting appropriate conservation targets. We used genetic data to identify population clusters and quantify gene flow over historical and contemporary time frames in the Diamondback Terrapin (Malaclemys terrapin). This species has a long and complicated history with humans, including commercial overharvesting and subsequent translocation events during the early twentieth century. Today, terrapins face threats from habitat loss and mortality in fisheries bycatch. To evaluate population structure and gene flow among Diamondback Terrapin populations in the Chesapeake Bay region, we sampled 617 individuals from 15 localities and screened individuals at 12 polymorphic microsatellite loci. Our goals were to demarcate metapopulation structure, quantify genetic diversity, estimate effective population sizes, and document temporal changes in gene flow. We found that terrapins in the Chesapeake Bay region harbour high levels of genetic diversity and form four populations. Effective population sizes were variable. Among most population comparisons, estimates of historical and contemporary terrapin gene flow were generally low (m ≈ 0.01). However, we detected a substantial increase in contemporary gene flow into Chesapeake Bay from populations outside the bay, as well as between two populations within Chesapeake Bay, possibly as a consequence of translocations during the early twentieth century. Our study shows that inferences across multiple time scales are needed to evaluate population connectivity, especially as recent changes may identify threats to population persistence.


Assuntos
Fluxo Gênico , Variação Genética , Genética Populacional , Tartarugas/genética , Animais , Baías , Maryland , Repetições de Microssatélites , Taxa de Mutação , Densidade Demográfica , Análise de Sequência de DNA , Análise Espaço-Temporal , Virginia
8.
Transgenic Res ; 24(1): 147-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25204701

RESUMO

Genome editing tools enable efficient and accurate genome manipulation. An enhanced ability to modify the genomes of livestock species could be utilized to improve disease resistance, productivity or breeding capability as well as the generation of new biomedical models. To date, with respect to the direct injection of genome editor mRNA into livestock zygotes, this technology has been limited to the generation of pigs with edited genomes. To capture the far-reaching applications of gene-editing, from disease modelling to agricultural improvement, the technology must be easily applied to a number of species using a variety of approaches. In this study, we demonstrate zygote injection of TALEN mRNA can also produce gene-edited cattle and sheep. In both species we have targeted the myostatin (MSTN) gene. In addition, we report a critical innovation for application of gene-editing to the cattle industry whereby gene-edited calves can be produced with specified genetics by ovum pickup, in vitro fertilization and zygote microinjection (OPU-IVF-ZM). This provides a practical alternative to somatic cell nuclear transfer for gene knockout or introgression of desirable alleles into a target breed/genetic line.


Assuntos
Animais Geneticamente Modificados/genética , Genoma , Miostatina/genética , Carneiro Doméstico/genética , Animais , Cruzamento , Bovinos , Fertilização in vitro , Engenharia Genética , Gado , Técnicas de Transferência Nuclear , Zigoto
9.
PLoS One ; 9(8): e102784, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25166503

RESUMO

The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an "endangered species threatened with extinction" in the US and "Vulnerable" on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci were scored as binary loci and the data were subjected to multivariate ordination, Bayesian clustering, hierarchical partitioning of variance, and among-population distance metric tests. The methods uncovered moderately high levels of gene diversity suggesting population structuring across and within three metapopulations (Northeast, Mid-Atlantic, and Southeast) that encompass seven demographically discrete and evolutionarily distinct lineages. The predicted groups are consistent with previously described behavioral patterns, especially dispersal and migration, supporting the interpretation that A. brevirostrum exhibit adaptive differences based on watershed. Combined with results of prior genetic (mitochondrial DNA) and behavioral studies, the current work suggests that dispersal is an important factor in maintaining genetic diversity in A. brevirostrum and that the basic unit for conservation management is arguably the local population.


Assuntos
Evolução Biológica , Peixes/genética , Variação Genética , Filogenia , Poliploidia , Alelos , Animais , Teorema de Bayes , Análise por Conglomerados , Espécies em Perigo de Extinção , Genética Populacional
10.
Sensors (Basel) ; 14(2): 2397-416, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24487623

RESUMO

This paper presents a ZigBee In-Patient Monitoring system embedded with a new ZigBee mobility management solution. The system enables ZigBee device mobility in a fixed ZigBee network. The usage, the architecture and the mobility framework are discussed in details in the paper. The evaluation shows that the new algorithm offers a good efficiency, resulting in a low management cost. In addition, the system can save lives by providing a panic button and can be used as a location tracking service. A case study focused on the Princes of Wales Hospital in Hong Kong is presented and findings are given. This investigation reveals that the developed mobile solutions offer promising value-added services for many potential ZigBee applications.

11.
Sci Rep ; 3: 2847, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24108318

RESUMO

Transcription activator-like effector nuclease (TALEN) and zinc finger nuclease (ZFN) genome editing technology enables site directed engineering of the genome. Here we demonstrate for the first time that both TALEN and ZFN injected directly into pig zygotes can produce live genome edited pigs. Monoallelic as well as heterozygous and homozygous biallelic events were identified, significantly broadening the use of genome editor technology in livestock by enabling gene knockout in zygotes from any chosen mating.


Assuntos
Animais Geneticamente Modificados/genética , Fertilização in vitro , Engenharia Genética , Genoma , Edição de RNA/genética , Dedos de Zinco/genética , Zigoto/citologia , Alelos , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Sequência de Bases , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Endonucleases/metabolismo , Feminino , Técnicas de Inativação de Genes , Homozigoto , Dados de Sequência Molecular , Técnicas de Transferência Nuclear , Homologia de Sequência do Ácido Nucleico , Suínos , Zigoto/metabolismo
12.
PLoS One ; 8(8): e71363, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977029

RESUMO

Large animal models are an important resource for the understanding of human disease and for evaluating the applicability of new therapies to human patients. For many diseases, such as cone dystrophy, research effort is hampered by the lack of such models. Lentiviral transgenesis is a methodology broadly applicable to animals from many different species. When conjugated to the expression of a dominant mutant protein, this technology offers an attractive approach to generate new large animal models in a heterogeneous background. We adopted this strategy to mimic the phenotype diversity encounter in humans and generate a cohort of pigs for cone dystrophy by expressing a dominant mutant allele of the guanylate cyclase 2D (GUCY2D) gene. Sixty percent of the piglets were transgenic, with mutant GUCY2D mRNA detected in the retina of all animals tested. Functional impairment of vision was observed among the transgenic pigs at 3 months of age, with a follow-up at 1 year indicating a subsequent slower progression of phenotype. Abnormal retina morphology, notably among the cone photoreceptor cell population, was observed exclusively amongst the transgenic animals. Of particular note, these transgenic animals were characterized by a range in the severity of the phenotype, reflecting the human clinical situation. We demonstrate that a transgenic approach using lentiviral vectors offers a powerful tool for large animal model development. Not only is the efficiency of transgenesis higher than conventional transgenic methodology but this technique also produces a heterogeneous cohort of transgenic animals that mimics the genetic variation encountered in human patients.


Assuntos
Animais Geneticamente Modificados , Heterogeneidade Genética , Guanilato Ciclase/genética , Células Fotorreceptoras Retinianas Cones/patologia , Distrofias Retinianas/genética , Transgenes , Sequência de Aminoácidos , Animais , Modelos Animais de Doenças , Eletrorretinografia , Genes Dominantes , Vetores Genéticos , Guanilato Ciclase/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Lentivirus/genética , Dados de Sequência Molecular , Mutação , Fenótipo , Células Fotorreceptoras Retinianas Cones/enzimologia , Distrofias Retinianas/patologia , Homologia de Sequência de Aminoácidos , Índice de Gravidade de Doença , Suínos/genética , Acuidade Visual
13.
Toxicology ; 294(2-3): 94-103, 2012 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-22365945

RESUMO

Organophosphorus (OP) insecticide self-poisoning is responsible for about one-quarter of global suicides. Treatment focuses on the fact that OP compounds inhibit acetylcholinesterase (AChE); however, AChE-reactivating drugs do not benefit poisoned humans. We therefore studied the role of solvent coformulants in OP toxicity in a novel minipig model of agricultural OP poisoning. Gottingen minipigs were orally poisoned with clinically relevant doses of agricultural emulsifiable concentrate (EC) dimethoate, dimethoate active ingredient (AI) alone, or solvents. Cardiorespiratory physiology and neuromuscular (NMJ) function, blood AChE activity, and arterial lactate concentration were monitored for 12h to assess poisoning severity. Poisoning with agricultural dimethoate EC40, but not saline, caused respiratory arrest within 30 min, severe distributive shock and NMJ dysfunction, that was similar to human poisoning. Mean arterial lactate rose to 15.6 [SD 2.8] mM in poisoned pigs compared to 1.4 [0.4] in controls. Moderate toxicity resulted from poisoning with dimethoate AI alone, or the major solvent cyclohexanone. Combining dimethoate with cyclohexanone reproduced severe poisoning characteristic of agricultural dimethoate EC poisoning. A formulation without cyclohexanone showed less mammalian toxicity. These results indicate that solvents play a crucial role in dimethoate toxicity. Regulatory assessment of pesticide toxicity should include solvents as well as the AIs which currently dominate the assessment. Reformulation of OP insecticides to ensure that the agricultural product has lower mammalian toxicity could result in fewer deaths after suicidal ingestion and rapidly reduce global suicide rates.


Assuntos
Inibidores da Colinesterase/intoxicação , Cicloexanonas/química , Dimetoato/intoxicação , Inseticidas/intoxicação , Solventes/química , Agricultura , Animais , Inibidores da Colinesterase/administração & dosagem , Dimetoato/administração & dosagem , Emulsões , Humanos , Inseticidas/administração & dosagem , Ácido Láctico/sangue , Masculino , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/metabolismo , Insuficiência Respiratória/induzido quimicamente , Choque/induzido quimicamente , Especificidade da Espécie , Suínos , Porco Miniatura
15.
Mol Ecol ; 19(15): 3088-100, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20584144

RESUMO

Populations of the American horseshoe crab, Limulus polyphemus, have declined, but neither the causes nor the magnitude are fully understood. In order to evaluate historic demography, variation at 12 microsatellite DNA loci surveyed in 1218 L. polyphemus sampled from 28 localities was analysed with Bayesian coalescent-based methods. The analysis showed strong declines in population sizes throughout the species' distribution except in the geographically isolated southern-most population in Mexico, where a strong increase in population size was inferred. Analyses suggested that demographic changes in the core of the distribution occurred in association with the recolonization after the Ice Age and also by anthropogenic effects, such as the past overharvest of the species for fertilizer or the current use of the animals as bait for American eel (Anguilla rostrata) and whelk (Busycon spp.) fisheries. This study highlights the importance of considering both climatic changes and anthropogenic effects in efforts to understand population dynamics--a topic which is highly relevant in the ongoing assessments of the effects of climate change and overharvest.


Assuntos
Genética Populacional , Caranguejos Ferradura/genética , Animais , Teorema de Bayes , Mudança Climática , Genótipo , Geografia , Desequilíbrio de Ligação , Repetições de Microssatélites , Modelos Genéticos , Densidade Demográfica , Dinâmica Populacional , Análise de Sequência de DNA
16.
BMC Gastroenterol ; 10: 34, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20353598

RESUMO

BACKGROUND: The development of effective therapies for acute liver failure (ALF) is limited by our knowledge of the pathophysiology of this condition, and the lack of suitable large animal models of acetaminophen toxicity. Our aim was to develop a reproducible invasively-monitored porcine model of acetaminophen-induced ALF. METHOD: 35kg pigs were maintained under general anaesthesia and invasively monitored. Control pigs received a saline infusion, whereas ALF pigs received acetaminophen intravenously for 12 hours to maintain blood concentrations between 200-300 mg/l. Animals surviving 28 hours were euthanased. RESULTS: Cytochrome p450 levels in phenobarbital pre-treated animals were significantly higher than non pre-treated animals (300 vs 100 pmol/mg protein). Control pigs (n = 4) survived 28-hour anaesthesia without incident. Of nine pigs that received acetaminophen, four survived 20 hours and two survived 28 hours. Injured animals developed hypotension (mean arterial pressure; 40.8 +/- 5.9 vs 59 +/- 2.0 mmHg), increased cardiac output (7.26 +/- 1.86 vs 3.30 +/- 0.40 l/min) and decreased systemic vascular resistance (8.48 +/- 2.75 vs 16.2 +/- 1.76 mPa/s/m3). Dyspnoea developed as liver injury progressed and the increased pulmonary vascular resistance (636 +/- 95 vs 301 +/- 26.9 mPa/s/m3) observed may reflect the development of respiratory distress syndrome.Liver damage was confirmed by deterioration in pH (7.23 +/- 0.05 vs 7.45 +/- 0.02) and prothrombin time (36 +/- 2 vs 8.9 +/- 0.3 seconds) compared with controls. Factor V and VII levels were reduced to 9.3 and 15.5% of starting values in injured animals. A marked increase in serum AST (471.5 +/- 210 vs 42 +/- 8.14) coincided with a marked reduction in serum albumin (11.5 +/- 1.71 vs 25 +/- 1 g/dL) in injured animals. Animals displayed evidence of renal impairment; mean creatinine levels 280.2 +/- 36.5 vs 131.6 +/- 9.33 mumol/l. Liver histology revealed evidence of severe centrilobular necrosis with coagulative necrosis. Marked renal tubular necrosis was also seen. Methaemoglobin levels did not rise >5%. Intracranial hypertension was not seen (ICP monitoring), but there was biochemical evidence of encephalopathy by the reduction of Fischer's ratio from 5.6 +/- 1.1 to 0.45 +/- 0.06. CONCLUSION: We have developed a reproducible large animal model of acetaminophen-induced liver failure, which allows in-depth investigation of the pathophysiological basis of this condition. Furthermore, this represents an important large animal model for testing artificial liver support systems.


Assuntos
Falência Hepática Aguda/diagnóstico , Monitorização Fisiológica/métodos , Acetaminofen/toxicidade , Animais , Sistema Enzimático do Citocromo P-450/sangue , Modelos Animais de Doenças , Progressão da Doença , Fator V/metabolismo , Fator VII/metabolismo , Pressão Intracraniana , Falência Hepática Aguda/sangue , Falência Hepática Aguda/induzido quimicamente , Espectroscopia de Ressonância Magnética , Prognóstico , Volume Sistólico , Taxa de Sobrevida , Suínos , Resistência Vascular
17.
Mol Reprod Dev ; 76(1): 61-4, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18449866

RESUMO

Lentiviral vectors have recently emerged as an efficient method of transgene delivery to the germline of animals. We now demonstrate that combining this efficiency with embryo splitting procedures enables the production of monozygotic twins, one of which is transgenic. We propose that this approach can be used to generate animals in which cell or tissue transplantation can be achieved without the use of immunosuppressive regimes.


Assuntos
Animais Geneticamente Modificados/metabolismo , Transplante de Células/métodos , Ovinos/genética , Ovinos/metabolismo , Transplante de Tecidos/métodos , Animais , Vetores Genéticos/genética , Lentivirus/genética , Transgenes/genética
18.
Mol Ecol Resour ; 8(2): 335-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21585784

RESUMO

In order to investigate a potential hybrid zone between the candy darter, Etheostoma osburni, and variegate darter, Etheostoma variatum, and examine population variation within E. osburni, a suite of primers for 15 polymorphic microsatellite loci were developed. The average number of alleles per locus was 5.5 in E. osburni and 7.6 in E. variatum, and the average observed heterozygosities were 62.5% and 71.4%, respectively. There were no deviations from Hardy-Weinberg equilibrium and no observed linkage disequilibrium after Bonferroni correction. The utility of these primers was also tested in 11 species of darters representing all four genera of darters. Success of cross-species amplification was largely consistent with phylogenetic relationships of darters.

19.
Mol Ecol Resour ; 8(5): 1037-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21585964

RESUMO

A suite of 13 polymorphic tri- and tetranucleotide microsatellite loci were isolated from the ahermatypic deep-sea coral, Lophelia pertusa. Among 51 individuals collected from three disjunct oceanic regions, allelic diversity ranged from six to 38 alleles and averaged 9.1 alleles per locus. Observed heterozygosity ranged from 9.1 to 96.8% and averaged 62.3% in the Gulf of Mexico population. For some loci, amplification success varied among collections, suggesting regional variation in priming site sequences. Four loci showed departures from Hardy-Weinberg equilibrium in certain collections which may reflect nonrandom mating.

20.
J Cell Biochem ; 103(1): 78-97, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17497683

RESUMO

Mitochondrial dysfunction, damage and mutations of mitochondrial proteins give rise to a range of ill understood patterns of disease. Although there is significant general knowledge of the proteins and the functional processes of the mitochondria, there is little knowledge of difference about how mitochondria respond and how they are regulated in different organs and tissues. Proteomic profiling of mitochondria and associated proteins involved in mitochondrial regulation and trafficking within cells and tissues has the potential to provide insights into mitochondrial dysfunction associated with many human diseases. The rat colon mitoproteome analysis presented here provides a useful tool to assist in identification and interpretation of mitochondrial dysfunction implicated in colon pathogenesis. 2DPAGE followed by LC/MS/MS was used to identify 430 proteins from mitochondrial enriched fractions prepared from rat colon, resulting in 195 different proteins or approximately 50% of the resolved proteins being identified as multiple protein expression forms. Proteins associated with the colon mitoproteome were involved in calcium binding, cell cycle, energy metabolism and electron transport chain, protein folding, protein synthesis and degradation, redox regulation, structural proteins, signalling and transporter and channel proteins. The mitochondrial associated proteins identified in this study of colon tissue complement and are compared with other recently published mitoproteome analyses from other organ tissues, and will assist in revealing potentially organ specific roles of the mitochondria and organ specific disease associated with mitochondrial dysfunction.


Assuntos
Colo/metabolismo , Proteínas Mitocondriais/metabolismo , Animais , Eletroforese em Gel Bidimensional , Citometria de Fluxo , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/classificação , Proteômica , Ratos , Ratos Sprague-Dawley
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