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BACKGROUND: Argonaute-2 (Ago2) is an essential component of microRNA biogenesis implicated in tumourigenesis. However Ago2 expression and localisation in breast cancer remains undetermined. The aim was to define Ago2 expression (mRNA and protein) and localisation in breast cancer, and investigate associations with clinicopathological details. METHODS: Ago2 protein was stained in breast cancer cell lines and tissue microarrays (TMAs), with intensity and localization assessed. Staining intensity was correlated with clinicopathological details. Using independent databases, Ago2 mRNA expression and gene alterations in breast cancer were investigated. RESULTS: In the breast cancer TMAs, 4 distinct staining intensities were observed (Negative, Weak, Moderate, Strong), with 64.2% of samples stained weak or negatively for Ago2 protein. An association was found between strong Ago2 staining and, the Her2 positive or basal subtypes, and between Ago2 intensity and receptor status (Estrogen or Progesterone). In tumours Ago2 mRNA expression correlated with reduced relapse free survival. Conversely, Ago2 mRNA was expressed significantly lower in SK-BR-3 (HER2 positive) and BT-20 (Basal/Triple negative) cell lines. Interestingly, high levels of Ago2 gene amplification (10-27%) were observed in breast cancer across multiple patient datasets. Importantly, knowledge of Ago2 expression improves predictions of breast cancer subtype by 20%, ER status by 15.7% and PR status by 17.5%. CONCLUSIONS: Quantification of Ago2 improves the stratification of breast cancer and suggests a differential role for Ago2 in breast cancer subtypes, based on levels and cellular localisation. Further investigation of the mechanisms affecting Ago2 dysregulation will reveal insights into the molecular differences underpinning breast cancer subtypes.
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Proteínas Argonautas/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas Argonautas/genética , Biomarcadores Tumorais/genética , Biópsia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Amplificação de Genes , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Mensageiro/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estatísticas não ParamétricasRESUMO
Reduced expression of the Gad1 gene-encoded 67-kDa protein isoform of glutamic acid decarboxylase (GAD67) is a hallmark of schizophrenia. GAD67 downregulation occurs in multiple interneuronal sub-populations, including the parvalbumin-positive (PVALB+) cells. To investigate the role of the PV-positive GABAergic interneurons in behavioral and molecular processes, we knocked down the Gad1 transcript using a microRNA engineered to target specifically Gad1 mRNA under the control of Pvalb bacterial artificial chromosome. Verification of construct expression was performed by immunohistochemistry. Follow-up electrophysiological studies revealed a significant reduction in γ-aminobutyric acid (GABA) release probability without alterations in postsynaptic membrane properties or changes in glutamatergic release probability in the prefrontal cortex pyramidal neurons. Behavioral characterization of our transgenic (Tg) mice uncovered that the Pvalb/Gad1 Tg mice have pronounced sensorimotor gating deficits, increased novelty-seeking and reduced fear extinction. Furthermore, NMDA (N-methyl-d-aspartate) receptor antagonism by ketamine had an opposing dose-dependent effect, suggesting that the differential dosage of ketamine might have divergent effects on behavioral processes. All behavioral studies were validated using a second cohort of animals. Our results suggest that reduction of GABAergic transmission from PVALB+ interneurons primarily impacts behavioral domains related to fear and novelty seeking and that these alterations might be related to the behavioral phenotype observed in schizophrenia.
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Comportamento Animal , Glutamato Descarboxilase/genética , Interneurônios/metabolismo , Parvalbuminas/metabolismo , Esquizofrenia/genética , Animais , Encéfalo/fisiologia , Modelos Animais de Doenças , Eletrofisiologia , Comportamento Exploratório , Medo , Inativação Gênica , Ketamina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Filtro Sensorial/genética , Transmissão SinápticaRESUMO
BACKGROUND: Active participation of consumers in health care decision making, policy and clinical research is increasingly encouraged by governments, influential bodies and funders. Identifying the best way to achieve this is difficult due to the paucity of evidence. Consumers have mixed feelings towards clinical practice guidelines (CPG) demonstrating scepticism towards their purpose and applicability to their needs. There is no information pertaining to consumers' views and attitudes on the receipt of antenatal corticosteroids (ACS). The aim of this study was to examine the barriers and enablers to receiving ACS and use of CPG amongst consumers. METHODS: Consumers were recruited from neonatal units across three district health boards (DHBs) in Auckland, New Zealand. Participants completed a semi-structured interview or questionnaire. The questions posed and analyses were informed by the Theoretical Domains Framework (TDF). Barriers and enablers were identified by the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on use of CPG and receipt of ACS. RESULTS: Twenty four consumers participated in the study. Six domains were identified as barriers to receipt of ACS and use of CPG. Key barriers to receipt of ACS included: difficulty retaining information conveyed, requiring further information in a variety of formats, and time constraints faced by consumers and health professionals in the provision and understanding of information to facilitate decision making. Barriers to use of CPG included: uncertainty about applicability of guideline use among consumers and scepticism about health professionals adhering too rigidly to guidelines. Enablers to receipt of ACS included: optimism toward ACS use, a strong knowledge of why ACS were administered, improved resilience in their pregnancy and confidence in their decision making following receipt of information about ACS. Enablers to use of CPG included: validation and standardisation of decision making among health professionals providing care and facilitating the best care for women and their babies. CONCLUSIONS: Key barriers and enablers exist among consumers regarding receipt of ACS and use of CPG. These need to be addressed or modified in any intervention strategy to facilitate implementation of the ACS CPG.
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Corticosteroides/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Guias de Prática Clínica como Assunto , Nascimento Prematuro/tratamento farmacológico , Cuidado Pré-Natal/psicologia , Adulto , Feminino , Fidelidade a Diretrizes , Humanos , Nova Zelândia , Gravidez , Cuidado Pré-Natal/normas , Pesquisa Qualitativa , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The ineffective implementation of evidence based practice guidelines can mean that the best health outcomes are not achieved. This study examined the barriers and enablers to the uptake and implementation of the new bi-national (Australia and New Zealand) antenatal corticosteroid clinical practice guidelines among health professionals, using the Theoretical Domains Framework. METHODS: Semi-structured interviews or online questionnaires were conducted across four health professional groups and three district health boards in Auckland, New Zealand. The questions were constructed to reflect the 14 behavioural domains from the Theoretical Domains Framework. Relevant domains were identified by the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on the behaviour using thematic analysis. The influence of health professional group and organisation on the different barriers and enablers identified were explored. RESULTS: Seventy-three health professionals completed either a semi-structured interview (n = 35) or on-line questionnaire (n = 38). Seven behavioural domains were identified as overarching enablers: belief about consequences; knowledge; social influences; environmental context and resource; belief about capabilities; social professional role and identity; and behavioural regulation. Five behavioural domains were identified as overarching barriers: environmental context and resources; knowledge; social influences; belief about consequences; and social professional role and identity. Differences in beliefs between individual health professional groups were identified within the domains: belief about consequences; social professional role and identity; and emotion. Organisational differences were identified within the domains: belief about consequences; social influences; and belief about capabilities. CONCLUSION: This study has identified some of the enablers and barriers to implementation of the New Zealand and Australian Antenatal Corticosteroid Clinical Practice Guidelines using the validated Theoretical Domains Framework, as perceived by health professionals. We have identified differences between individual health professional groups and organisations. The identification of these behavioural determinants can be used to enhance an implementation strategy, assist in the design of interventions to achieve improved implementation and facilitate process evaluations to understand why or how change interventions are effective.
Assuntos
Corticosteroides/uso terapêutico , Guias de Prática Clínica como Assunto , Cuidado Pré-Natal/métodos , Adulto , Atitude do Pessoal de Saúde , Austrália , Prática Clínica Baseada em Evidências , Feminino , Fidelidade a Diretrizes , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Inovação Organizacional , Percepção , Prática Profissional , Papel Profissional , Adulto JovemRESUMO
To design an efficient survey or monitoring program for a natural resource it is important to consider the spatial distribution of the resource. Generally, sample designs that are spatially balanced are more efficient than designs which are not. A spatially balanced design selects a sample that is evenly distributed over the extent of the resource. In this article we present a new spatially balanced design that can be used to select a sample from discrete and continuous populations in multi-dimensional space. The design, which we call balanced acceptance sampling, utilizes the Halton sequence to assure spatial diversity of selected locations. Targeted inclusion probabilities are achieved by acceptance sampling. The BAS design is conceptually simpler than competing spatially balanced designs, executes faster, and achieves better spatial balance as measured by a number of quantities. The algorithm has been programed in an R package freely available for download.
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Conservação dos Recursos Naturais/estatística & dados numéricos , Monitoramento Ambiental/estatística & dados numéricos , Algoritmos , Biometria/métodos , Simulação por Computador , Modelos Estatísticos , Tamanho da AmostraRESUMO
Canadian transport practices for shipments of newly weaned piglets are not well-described despite documentation requirements for those conducting the movement of these animals. The objective of this study was to describe the characteristics of weaned piglet transport events that occurred between 2014 and 2018 using records provided by five Canadian swine companies. Following cleaning and validation, the dataset included records from 6203 transport events involving the transport of approximately 6.9 million piglets (5.7 kg, 4.1-7.9 kg) from 62 origin sites in Alberta, Ontario, or Saskatchewan, Canada. This represents approximately 4.7% of the piglets estimated to have been weaned in Canada between 2014 and 2018, and 1.7% of sow farms in Canada according to 2016 National census data. Most transport events ended at farms in Canada (71.3%), while the remaining delivered piglets to one of eight American states. The predominant trailer types used were Straightdeck (51.4%) and Potbelly (36.6%), but this did not reflect the number of piglets transported as Potbelly trailers have greater load capacity. Transport events most frequently involved loading piglets from one origin barn and delivering them to a single destination barn (78.1%). Only transport events involving export to the United States picked up piglets from, or delivered them to, more than one farm site. Most transport events had very short trip distances (median distance: 48.0 km; IQR: 497.0), but a marked range was observed (1.8-2931.2 km). Average daily temperature data matched to the transport records by origin and destination location demonstrated ambient environmental conditions during these transport events ranged from - 30.3-28.7 °C. Overall, less than 10% of transport events had mortality occur. Comparable with other observational studies documenting weaned piglet mortality, the average in-transit mortality rate observed over the multiple seasons, companies, trip distances, and other characteristics in this dataset was 0.027%. However, instances of mortality over 1% did sporadically occur and could translate to considerable losses given the large load sizes common for piglets of this age and size (median load size: 1105 piglets; IQR: 1036 piglets). These data provide a better understanding of the interconnectedness of the Canadian swine industry as well as common transport practices which may inform future research on disease transmission in swine transport networks, or piglet welfare during transport. Additionally, variables that were not present in this dataset that would further strengthen these types of investigations are highlighted (e.g., space allowance).
Assuntos
Desmame , Animais , Suínos , Feminino , Alberta , Ontário , Saskatchewan , Estações do AnoRESUMO
North American swine producers commonly transport piglets away from sow farms at weaning. However, limited information on factors associated with piglet mortality during these transports is available. The objectives of this study were to identify transport characteristics that were associated with the occurrence of in-transit mortality (≥1 piglet found dead on arrival) and/or associated with increased rates of in-transit mortality using records of weaned piglet transport voluntarily provided by Canadian swine companies. Following cleaning and validation, records of 810 long duration (>8 h to <28 h) weaned piglet (min.: 4.2, max.: 7.7 kg) transports conducted between 2016 and 2017 by four companies were available to investigate risk factors for the occurrence of in-transit mortality. Transports originated in Ontario, Saskatchewan, or Alberta and 30% of transports had one or more mortality events recorded. Season of transport was significant in the final logistic regression model; the odds of a transport having mortality occur was greater during the winter (December, January, February) compared to the spring (March, April, May) (OR=1.8; 95% CI: 1.13-2.96; P = 0.013), summer (June, July, August) (OR= 2.1; 95% CI: 1.28-3.34; P = 0.003) and fall (September, October, November) (OR=2.2; 95% CI: 1.36-3.62; P = 0.001), with no differences observed between the other seasons. Additionally, records from 755 long duration weaned piglet (min.: 4.2, max.: 7.9 kg) transports conducted between 2014 and 2017 by a single company was used to identify risk factors for increased rates of in-transit mortality. Transports originated in Saskatchewan or Alberta and 44.9% of transports had one or more mortality events recorded with in-transit mortality rates ranging from 0.00% to 6.16%. Season of transport was again significant in the final negative binomial regression model. The rate of piglet death in-transit was increased in all seasons compared to the summer with winter transport having the highest predicted rate of in-transit mortality. Transports conducted during the winter had a rate of in-transit mortality nearly five times greater compared to transports conducted during the summer (IRR= 4.94; 95% CI: 3.11-7.87; P = 0.000) and approximately three times greater compared to transports conducted during the fall (IRR=2.7; 95% CI: 1.73-4.30; P = 0.000) and spring (IRR=3.1; 95% CI: 1.96-4.99; P = 0.000). These results suggest that winter transport in Western Canada is an area of opportunity to reduce in-transit mortality during long duration weaned piglet transport. Research investigating transport practices that may mitigate the effects of extreme cold (e.g., space allowance, bedding provision) would be useful for informing specific recommendations for this age group.
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Bem-Estar do Animal , Suínos , Animais , Feminino , Estações do Ano , Desmame , Fatores de Tempo , AlbertaRESUMO
The endemic Pyrenean Desman (Galemys pyrenaicus) is an elusive, rare, and vulnerable species declining over its entire and narrow range (Spain, Portugal, France, and Andorra). The principal set of conservation measures in France is a 5-years National Action Plan based on 25 conservation actions. Priority is given to update its present distribution and develop tools for predictive distribution models. We aim at building the first species distribution model and map for the northern edge of the range of the Desman and confronting the outputs of the model to target conservation efforts in the context of environmental change. Contrasting to former comparable studies, we derive a simpler model emphasizing the importance of factors linked to precipitation and not to the temperature. If temperature is one of the climate change key factors, depicted shrinkage in Desman distribution could be lower or null at the northern (French) edge suggesting thus a major role for this northern population in terms of conservation of the species. Finally, we question the applied issue of temporal and spatial transferability for such environmental favourability models when it is made at the edge of the distribution range.
Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Eulipotyphla/fisiologia , Modelos Biológicos , Andorra , Animais , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , França , Geografia , Portugal , EspanhaRESUMO
To achieve the lowest risk level for various cancers, individuals would engage in several healthy lifestyle behaviors and age-eligible cancer screenings as recommended. Nonetheless, research has largely omitted exploration of concurrent primary and secondary prevention behaviors. This study was designed to explore influences of cervical cancer screening among physically active women who reported participation in recreational sports. U.S. based women between the ages of 21-49, who had never been diagnosed with cancer, were eligible to complete a web-based survey. Logistic regression analyses were conducted using SAS 9.4. On average, women were 31 years of age (N = 394) and self-identified as Black (51.3 %). Although low overall (30.7 %), higher odds of cervical cancer screening were associated with age (OR = 1.06, 95 % CI = 1.03-1.10), employment (OR = 2.43, 95 % CI = 1.14-5.18), knowledge of cancer-related risk behaviors (OR = 4.04, 95 % CI = 1.33-12.28), routine doctor's visit (OR = 4.25, 95 % CI = 1.56-11.54), and team-based vs individual-based sport participation (OR = 1.95, 95 % CI = 1.13-3.34). Our study provides insight into the health profile of physically active women, ages 21-49, as it relates to risks for cervical cancer. Screening uptake among this diverse sample was much lower than the general population and national goals set by Healthy People 2030. Interventions should be tailored to increase knowledge of cancer-related risk behaviors, access to healthcare, and recommended cervical cancer screenings among even assumed-to-be healthy populations.
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To determine the safety of using argon as a deuteron beam stopping material, the 40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of natAr gas. After each irradiation, the gas chamber's 41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by â¼40%.
Assuntos
CiclotronsRESUMO
This study explored the relative competitive ability and performance of first-feeding growth hormone (GH) transgenic and non-transgenic Atlantic salmon Salmo salar fry under low food conditions. Pair-wise dominance trials indicated a strong competitive advantage for residents of a contested foraging territory. Transgenic and non-transgenic individuals, however, were equally likely to be dominant. Similarly, in stream environments with limited food, the transgene did not influence the growth in mass or survival at high or low fry densities. Fry in low-density treatments, however, performed better than fry in high-density treatments. These results indicate that, under the environment examined, the growth performance of GH-transgenic and non-transgenic S. salar may be similar during first feeding, an intense period of selection in their life history. Similarities in competitive ability and growth performance with wild-type fish suggest that the capacity of transgenic S. salar to establish in natural streams may not be inhibited during early life history.
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Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Rios , Salmo salar/fisiologia , Predomínio Social , Animais , Comportamento Competitivo/fisiologia , Ecossistema , Técnicas de Transferência de Genes/veterinária , Densidade Demográfica , Salmo salar/genética , Salmo salar/crescimento & desenvolvimento , Análise de Sobrevida , Transgenes/genéticaRESUMO
Global climate change increasingly contributes to large changes in ecosystem structure. Timely management of rapidly changing marine ecosystems must be matched with methods to rapidly quantify and assess climate driven impacts to ecological communities. Here we create a species-specific, classification system for fish thermal affinities, using three quantifiable datasets and expert opinion. Multiple sources of information limit potential data bias and avoid misclassification. Using a temperate kelp forest fish community in California, USA as a test case for this new methodology, we found the majority of species had high classification agreement across all four data sources (n = 78) but also a number of low agreement species (2 sources disagree from the others, n = 47). For species with low agreement, use of just one dataset to classify species, as is commonly done, would lead to high risk of misclassification. Differences in species classification between individual datasets and our composite classification were apparent. Applying different thermal classifications, lead to different conclusions when quantifying 'warm' and 'cool' species density responses to a marine heatwave. Managers can use this classification approach as a tool to generate accurate, timely and simple information for resource management.
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Conservação dos Recursos Naturais/métodos , Peixes/classificação , Kelp/classificação , Animais , Biota , California , Mudança Climática , Bases de Dados Factuais , Tomada de Decisões , Humanos , Especificidade da Espécie , TemperaturaRESUMO
Our understanding of the role of the parabrachial nucleus (PBN) has evolved as technology has advanced, in part due to cell-specific studies and complex behavioral assays. This is reflected in the heterogeneous neuronal populations within the PBN to the extended amygdala (EA) circuits which encompass the bed nucleus of the stria terminalis (BNST) and central amygdala (CeA) circuitry, as they differentially modulate aspects of behavior in response to diverse threat-like contexts necessary for survival. Here we review how the PBNâCeA and PBNâBNST pathways differentially modulate fear-like behavior, innate and conditioned, through unique changes in neurotransmission in response to stress-inducing contexts. Furthermore, we hypothesize how in specific instances the PBNâCeA and PBNâBNST circuits are redundant and in part intertwined with their respective reciprocal projections. By deconstructing the interoceptive and exteroceptive components of affect- and stress related behavioral paradigms, evidence suggests that the PBNâCeA circuit modulates innate response to physical stimuli and fear conditioning. Conversely, the PBNâBNST circuit modulates distress-like stress in unpredictable contexts. Thereby, the PBN provides a pathway for alarming interoceptive and exteroceptive stimuli to be processed and relayed to the EA to induce stress-relevant affect. Additionally, we provide a framework for future studies to detail the cell-type specific intricacies of PBNâEA circuits in mediating behavioral responses to threats, and the relevance of the PBN in drug-use as it relates to threat and negative reinforcement. This article is part of the special Issue on 'Neurocircuitry Modulating Drug and Alcohol Abuse'.
Assuntos
Afeto/fisiologia , Tonsila do Cerebelo/fisiologia , Núcleos Parabraquiais/fisiologia , Estresse Psicológico/psicologia , Animais , Medo , Humanos , Núcleos Septais/fisiologiaRESUMO
A prototype of a novel bone-conduction hearing actuator based on a piezoelectric bending actuator is presented. The device lies flat against the skull which would allow it to form the basis of a subcutaneous bone-anchored hearing aid. The actuator excites bending in bone through a local bending moment rather than the application of a point force as with conventional bone-anchored hearing aids. Through measurements of the cochlear velocity created by the actuator in embalmed human heads, the device is shown to exhibit high efficiency, making it a possible alternative to present-day electromagnetic bone-vibration actuators.
Assuntos
Condução Óssea , Auxiliares de Audição , Perda Auditiva/reabilitação , Idoso , Cadáver , Elasticidade , Desenho de Equipamento , Feminino , Perda Auditiva/fisiopatologia , Humanos , Masculino , Teste de Materiais , Mecanotransdução Celular , Pessoa de Meia-Idade , Crânio/anatomia & histologia , VibraçãoRESUMO
Intravenous infusion of angiotensin II ([Asn¹ Val5]-Ang II) at 10â»9 mol min⻹ kg⻹ body mass produced a significant antidiuresis in river lamprey Lampetra fluviatilis, captured during upstream migration and maintained in fresh water. Although the renin-angiotensin hormonal system (RAS) is now recognized in jawless fishes, until this study, the role of homologous Ang II in L. fluviatilis kidney function had not been examined. This study provides the first evidence for an antidiuretic action of Ang II in cyclostomes and, in evolutionary terms, suggests a renal function for the RAS in early vertebrates.
Assuntos
Angiotensina II/farmacologia , Antidiuréticos/farmacologia , Rim/fisiologia , Lampreias/fisiologia , Sistema Renina-Angiotensina , Animais , Água Doce , Concentração Osmolar , Urina/químicaRESUMO
Acute climate events like marine heatwaves have the potential to temporarily or permanently alter community structure with effects on biodiversity and ecosystem services. We aimed to quantify the magnitude and consistency of climate driven community shifts inside and outside Marine Protected Areas before and after a marine heatwave using a kelp forest fish community dataset in southern California, USA. Abundance, biomass, diversity and recruitment of warm-water affinity species during the marine heatwave were significantly greater compared with prior years yet cool-water affinity species did not show commensurate declines. Fish communities inside MPAs were not buffered from these community shifts. This result is likely because the particular species most responsible for the community response to environmental drivers, were not fisheries targets. Resource managers working to preserve biodiversity in a changing climate will need to consider additional management tools and strategies in combination with protected areas to mitigate the effect of warming on marine communities.
Assuntos
Espécies em Perigo de Extinção , Peixes/fisiologia , Temperatura Alta , Distribuição Animal , Animais , Biomassa , Mudança Climática , Oceanos e MaresRESUMO
In only a few months, the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic, leaving physicians, scientists, and public health officials racing to understand, treat, and contain this zoonotic disease. SARS-CoV-2 has made the leap from animals to humans, but little is known about variations in species susceptibility that could identify potential reservoir species, animal models, and the risk to pets, wildlife, and livestock. While there is evidence that certain species, such as cats, are susceptible, the vast majority of animal species, including those in close contact with humans, have unknown susceptibility. Hence, methods to predict their infection risk are urgently needed. SARS-CoV-2 spike protein binding to angiotensin converting enzyme 2 (ACE2) is critical for viral cell entry and infection. Here we identified key ACE2 residues that distinguish susceptible from resistant species using in-depth sequence and structural analyses of ACE2 and its binding to SARS-CoV-2. Our findings have important implications for identification of ACE2 and SARS-CoV-2 residues for therapeutic targeting and identification of animal species with increased susceptibility for infection on which to focus research and protection measures for environmental and public health.
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Lysosomal enzymes have been shown to be synthesized as microsomal precursors, which are processed to mature enzymes located in lysosomes. We examined the effect of ammonium chloride on the intracellular processing and secretion of two lysosomal enzymes, beta-glucuronidase and beta-galactosidase, in mouse macrophages. This lysosomotropic drug caused extensive secretion of both precursor and mature enzyme forms within a few hours, as documented by pulse radiolabeling and molecular weight analysis. The normal intracellular route for processing and secretion of precursor enzyme was altered in treated cells. A small percentage of each precursor was delivered to the lysosomal organelle slowly. Most precursor forms traversed the Golgi apparatus, underwent further processing of carbohydrate moieties, and were then secreted in a manner similar to secretory proteins. The lag time for secretion of newly synthesized beta-galactosidase precursor was notably longer than that for the beta-glucuronidase precursor. The source of the secreted mature enzyme was the lysosomal organelle. Macrophages from the pale ear mutant were markedly deficient in secretion of mature lysosomal enzyme but secreted precursor forms normally. These results suggest that ammonia-treated macrophages contain two distinct intracellular pathways for secretion of lysosomal enzymes and that a specific block in the release of lysosomal contents occurs in the pale ear mutant.
Assuntos
Cloreto de Amônio/farmacologia , Galactosidases/metabolismo , Glucuronidase/metabolismo , Lisossomos/enzimologia , Macrófagos/enzimologia , beta-Galactosidase/metabolismo , Animais , Feminino , Glucuronidase/genética , Glucuronidase/isolamento & purificação , Cinética , Lisossomos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Peso Molecular , Mutação , Precursores de Proteínas/metabolismo , Frações Subcelulares/enzimologia , beta-Galactosidase/genética , beta-Galactosidase/isolamento & purificaçãoRESUMO
Two maternally derived chromosome sets and both maternal histocompatibility antigen haplotypes were identified in the tissues of a malformed triploid acardiac twin that developed within the same chorion as its normal twin. These findings indicate that the twins arose as a result of independent fertilizations, by two different spermatozoa, of a normal haploid ovum and its diploid first-meiotic-division polar body.