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1.
Cell ; 159(2): 428-39, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25303535

RESUMO

The generation of insulin-producing pancreatic ß cells from stem cells in vitro would provide an unprecedented cell source for drug discovery and cell transplantation therapy in diabetes. However, insulin-producing cells previously generated from human pluripotent stem cells (hPSC) lack many functional characteristics of bona fide ß cells. Here, we report a scalable differentiation protocol that can generate hundreds of millions of glucose-responsive ß cells from hPSC in vitro. These stem-cell-derived ß cells (SC-ß) express markers found in mature ß cells, flux Ca(2+) in response to glucose, package insulin into secretory granules, and secrete quantities of insulin comparable to adult ß cells in response to multiple sequential glucose challenges in vitro. Furthermore, these cells secrete human insulin into the serum of mice shortly after transplantation in a glucose-regulated manner, and transplantation of these cells ameliorates hyperglycemia in diabetic mice.


Assuntos
Técnicas de Cultura de Células , Células Secretoras de Insulina/citologia , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/genética , Insulina/metabolismo , Ilhotas Pancreáticas , Camundongos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo
2.
Nature ; 569(7756): 368-373, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31068696

RESUMO

In vitro differentiation of human stem cells can produce pancreatic ß-cells; the loss of this insulin-secreting cell type underlies type 1 diabetes. Here, as a step towards understanding this differentiation process, we report the transcriptional profiling of more than 100,000 human cells undergoing in vitro ß-cell differentiation, and describe the cells that emerged. We resolve populations that correspond to ß-cells, α-like poly-hormonal cells, non-endocrine cells that resemble pancreatic exocrine cells and a previously unreported population that resembles enterochromaffin cells. We show that endocrine cells maintain their identity in culture in the absence of exogenous growth factors, and that changes in gene expression associated with in vivo ß-cell maturation are recapitulated in vitro. We implement a scalable re-aggregation technique to deplete non-endocrine cells and identify CD49a (also known as ITGA1) as a surface marker of the ß-cell population, which allows magnetic sorting to a purity of 80%. Finally, we use a high-resolution sequencing time course to characterize gene-expression dynamics during the induction of human pancreatic endocrine cells, from which we develop a lineage model of in vitro ß-cell differentiation. This study provides a perspective on human stem-cell differentiation, and will guide future endeavours that focus on the differentiation of pancreatic islet cells, and their applications in regenerative medicine.


Assuntos
Diferenciação Celular , Células Secretoras de Insulina/citologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Linhagem da Célula , Separação Celular , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/classificação , Células Secretoras de Insulina/metabolismo , Integrina alfa1/metabolismo , Masculino , Camundongos , RNA-Seq , Análise de Célula Única , Células-Tronco/metabolismo
3.
J Am Chem Soc ; 146(22): 15596-15608, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38771258

RESUMO

Transition metal-catalyzed alkene isomerization is an enabling technology used to install an alkene distal to its original site. Due to their well-defined structure, homogeneous catalysts can be fine-tuned to optimize reactivity, stereoselectivity, and positional selectivity, but they often suffer from instability and nonrecyclability. Heterogeneous catalysts are generally highly robust but continue to lack active-site specificity and are challenging to rationally improve through structural modification. Known single-site heterogeneous catalysts for alkene isomerization utilize precious metals and bespoke, expensive, and synthetically intense supports. Additionally, they generally have mediocre reactivity, inspiring us to develop a heterogeneous catalyst with an active site made from readily available compounds made of Earth-abundant elements. Previous work demonstrated that a very active homogeneous catalyst is formed upon protonation of Ni[P(OEt)3]4 by H2SO4, generating a [Ni-H]+ active site. This catalyst is incredibly active, but also decomposes readily, which severely limits its utility. Herein we show that by using a solid acid (sulfated zirconia, SZO300), not only is this decomposition prevented, but high activity is maintained, improved selectivity is achieved, and a broader scope of functional groups is tolerated. Preliminary mechanistic experiments suggest that the catalytic reaction likely goes through an intermolecular, two-electron pathway. A detailed kinetic study comparing the state-of-the-art Ni and Pd isomerization catalysts reveals that the highest activity and selectivity is seen with the Ni/SZO300 system. The reactivity of Ni/SZO300, is not limited to alkene isomerization; it is also a competent catalyst for hydroalkenylation, hydroboration, and hydrosilylation, demonstrating the broad application of this heterogeneous catalyst.

4.
Langmuir ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38318799

RESUMO

There is a critical need for sorting complex materials, such as pancreatic islets of Langerhans, exocrine acinar tissues, and embryoid bodies. These materials are cell clusters, which have highly heterogeneous physical properties (such as size, shape, morphology, and deformability). Selecting such materials on the basis of specific properties can improve clinical outcomes and help advance biomedical research. In this work, we focused on sorting one such complex material, human stem cell-derived ß cell clusters (SC-ß cell clusters), by size. For this purpose, we developed a microfluidic device in which an image detection system was coupled to an actuation mechanism based on traveling surface acoustic waves (TSAWs). SC-ß cell clusters of varying size (∼100-500 µm in diameter) were passed through the sorting device. Inside the device, the size of each cluster was estimated from their bright-field images. After size identification, larger clusters, relative to the cutoff size for separation, were selectively actuated using TSAW pulses. As a result of this selective actuation, smaller and larger clusters exited the device from different outlets. At the current sample dilutions, the experimental sorting efficiency ranged between 78% and 90% for a separation cutoff size of 250 µm, yielding sorting throughputs of up to 0.2 SC-ß cell clusters/s using our proof-of-concept design. The biocompatibility of this sorting technique was also established, as no difference in SC-ß cell cluster viability due to TSAW pulse usage was found. We conclude the proof-of-concept sorting work by discussing a few ways to optimize sorting of SC-ß cell clusters for potentially higher sorting efficiency and throughput. This sorting technique can potentially help in achieving a better distribution of islets for clinical islet transplantation (a potential cure for type 1 diabetes). Additionally, the use of this technique for sorting islets can help in characterizing islet biophysical properties by size and selecting suitable islets for improved islet cryopreservation.

5.
Int J Mol Sci ; 25(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256143

RESUMO

Cytochrome P450s (CYP450s) are a versatile superfamily of enzymes known to undergo rapid evolution. They have important roles across growth and development pathways in crustaceans, although it is difficult to characterise orthologs between species due to their sequence diversity. Conserved CYP450s enzymes in crustaceans are those associated with ecdysteroidogenesis: synthesising and breaking down the active moult hormone, 20-hydroxyecdysone. The complex life cycle of the ornate spiny lobster, Panulirus ornatus, relies on moulting in order to grow and develop. Many of these diverse life stages have been analysed to establish a comprehensive transcriptomic database for this species. The transcripts putatively encoding for CYP450s were mapped using transcriptomic analysis and identified across growth and development stages. With the aid of phylogeny, 28 transcripts of 42 putative P. ornatus CYP450s were annotated, including the well conserved Halloween genes, which are involved in ecdysteroidogenesis. Expression patterns across the life stages determined that only a subset of the CYP450s can be detected in each life stage or tissue. Four Shed transcripts show overlapping expression between metamorphosis and adult tissues, suggesting pleotropic functions of the multiple Shed orthologs within P. ornatus.


Assuntos
Palinuridae , Animais , Palinuridae/genética , Sistema Enzimático do Citocromo P-450/genética , Muda , Metamorfose Biológica/genética , Bases de Dados Factuais
6.
BMC Med ; 21(1): 9, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36600296

RESUMO

BACKGROUND: Understanding the relationship between chronic pain conditions and suicidal behavior-suicide attempt, other intentional self-harm, and death by suicide-is imperative for suicide prevention efforts. Although chronic pain conditions are associated with suicidal behaviors, these associations might be attributed to unmeasured confounding or mediated via pain comorbidity. METHODS: We linked a population-based Swedish twin study (N=17,148 twins) with 10 years of longitudinal, nationwide records of suicidal behavior from health and mortality registers through 2016. To investigate whether pain comorbidity versus specific pain conditions were more important for later suicidal behavior, we modeled a general factor of pain and two independent specific pain factors (measuring pain-related somatic symptoms and neck-shoulder pain, respectively) based on 9 self-reported chronic pain conditions. To examine whether the pain-suicidal behavior associations were attributable to familial confounding, we applied a co-twin control model. RESULTS: Individuals scoring one standard deviation above the mean on the general pain factor had a 51% higher risk of experiencing suicidal behavior (odds ratio (OR), 1.51; 95% confidence interval (CI), 1.34-1.72). The specific factor of somatic pain was also associated with increased risk for suicidal behavior (OR, 1.80; 95% CI, 1.45-2.22]). However, after adjustment for familial confounding, the associations were greatly attenuated and not statistically significant within monozygotic twin pairs (general pain factor OR, 0.89; 95% CI, 0.59-1.33; somatic pain factor OR, 1.02; 95% CI, 0.49-2.11) CONCLUSION: Clinicians might benefit from measuring not only specific types of pain, but also pain comorbidity; however, treating pain might not necessarily reduce future suicidal behavior, as the associations appeared attributable to familial confounding.


Assuntos
Dor Crônica , Dor Nociceptiva , Humanos , Ideação Suicida , Dor Crônica/epidemiologia , Estudos Longitudinais , Gêmeos Monozigóticos , Fatores de Risco , Doença Crônica
7.
Gen Comp Endocrinol ; 332: 114183, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36471526

RESUMO

Neuropeptides are commonly produced in the neural tissues yet can have effects on far-reaching targets, with varied biological responses. We describe here the neuropeptidome of the ornate spiny lobster, Panulirus ornatus, a species of emerging importance to closed-system aquaculture, with a focus on peptide hormones produced by the reproductive tissues. Transcripts for a precursor to one neuropeptide, adipokinetic hormone/corazonin-related peptide (ACP) were identified in high numbers in the sperm duct of adult spiny lobsters suggesting a role for ACP in the reproduction of this species. Neuropeptide production in the sperm duct may be linked with physiological control of spermatophore production in the male, or alternatively may function in signalling to the female. The enzymes which process nascent neuropeptide precursors into their mature, active forms have seldom been studied in decapods, and never before at the multi-tissue level. We have identified transcripts for multiple members of the proprotein convertase subtisilin/kexin family in the ornate spiny lobster, with some enzymes showing specificity to certain tissues. In addition, other enzyme transcripts involved with neuropeptide processing are identified along with their tissue and life stage expression patterns.


Assuntos
Neuropeptídeos , Palinuridae , Hormônios Peptídicos , Animais , Masculino , Feminino , Palinuridae/metabolismo , Hormônios Peptídicos/metabolismo , Sêmen/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo
8.
J Endocrinol Invest ; 45(10): 1899-1908, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35612811

RESUMO

PURPOSE: Adrenalectomies performed for the treatment of primary aldosteronism due to unilateral adenoma are traditionally confirmed with, and guided by, results from adrenal vein sampling (AVS). However, the usefulness of AVS at the expense of cost and complications is debated, and many institutions have independent protocols that use AVS to varying degrees. METHODS: Cost-effectiveness of AVS- vs computed tomography (CT)-based adrenalectomy was calculated using decision tree models. The tree was populated with values describing biochemical post-operative outcomes from the published literature; patients were placed into AVS- or CT-dependent treatment arms. Biochemical outcomes were defined based on patients' potassium levels and aldosterone-renin ratios. Patients underwent adrenalectomies and received medical management dosed based on surgical outcomes. Costs were represented by Medicare (FY2021) reimbursement rates (US$) and quality-adjusted life-years (QALYs) were calculated using published morbidity and survival data. A willingness-to-pay of $100,000 per QALY gained was set to determine the most cost-effective strategy. The primary outcome was the incremental cost-effectiveness ratio (ICER) associated with biochemical outcomes. RESULTS: The base case analyses favored the use of AVS-guided care, which cost $307.65 more but yielded 0.78 more QALYs, resulting in an ICER of $392.57. These results were upheld by all one-way and two-way sensitivity analyses. In 100,000 random-sampling simulations, AVS-guided care was favored 100% of the time. CONCLUSIONS: For patients with primary aldosteronism receiving adrenalectomies with curative intent, the more cost-effective method based on biochemical outcomes is AVS-based care. Recent literature suggests biochemical resolution should be favored over clinical resolution, due to long-term detriments of increased aldosterone independent of clinical symptoms.


Assuntos
Adrenalectomia , Hiperaldosteronismo , Adrenalectomia/economia , Adrenalectomia/métodos , Idoso , Aldosterona , Análise Custo-Benefício , Humanos , Hiperaldosteronismo/diagnóstico por imagem , Hiperaldosteronismo/cirurgia , Medicare , Tomografia Computadorizada por Raios X/métodos , Estados Unidos
9.
Artigo em Inglês | MEDLINE | ID: mdl-34822975

RESUMO

Apparent digestibility and gastrointestinal evacuation rate were measured to assess the potential of five commercially available protein sources for their inclusion in feeds for juvenile slipper lobster, Thenus australiensis. Protein sources tested were fishmeal, krill meal, lupin meal, soybean meal and squid by-product meal. Apparent digestibility of crude protein ranged from 79.6% to 95.3%, with fishmeal protein significantly less digestible than lupin meal, squid by-product meal and soybean meal. Gastrointestinal evacuation rate was estimated from marker replacement, where yttrium oxide replaced ytterbium oxide. Faeces were collected every 3 h for 48 h, and a kinetic model was used to calculate the rate and time for the second marker to replace the first marker. Gastrointestinal evacuation (≥ 95%) was completed between 4 and 6 h with no significant differences among protein sources. Faeces consisted of both markers in equal parts 2.7 to 5.0 h after the feed switch, with lupin meal reaching the midpoint significantly faster than squid by-product meal and reference feed. The present study is the first in crustaceans to examine the relationship between apparent digestibility and gastrointestinal evacuation, showing more digestible protein sources had slower evacuation rates. The combined approach provides deeper insight into crustaceans' digestive physiology and helps understand their ability to digest specific ingredients. Further research is recommended to understand protein requirements in a broader context to verify highly digestible protein sources meet all nutritional requirements.


Assuntos
Ração Animal , Nephropidae , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Digestão/fisiologia , Fezes , Trato Gastrointestinal , Glycine max/metabolismo
10.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233053

RESUMO

RNA interference (RNAi) has been widely utilised in many invertebrate models since its discovery, and in a majority of instances presents as a highly efficient and potent gene silencing mechanism. This is emphasized in crustaceans with almost all taxa having the capacity to trigger effective silencing, with a notable exception in the spiny lobsters where repeated attempts at dsRNA induced RNAi have demonstrated extremely ineffective gene knockdown. A comparison of the core RNAi machinery in transcriptomic data from spiny lobsters (Panulirus ornatus) and the closely related slipper lobsters (Thenus australiensis, where silencing is highly effective) revealed that both lobsters possess all proteins involved in the small interfering and microRNA pathways, and that there was little difference at both the sequence and domain architecture level. Comparing the expression of these genes however demonstrated that T. australiensis had significantly higher expression in the transcripts encoding proteins which directly interact with dsRNA when compared to P. ornatus, validated via qPCR. These results suggest that low expression of the core RNAi genes may be hindering the silencing response in P. ornatus, and suggest that it may be critical to enhance the expression of these genes to induce efficient silencing in spiny lobsters.


Assuntos
Decápodes , MicroRNAs , Palinuridae , Animais , Palinuridae/genética , Interferência de RNA , Transcriptoma
11.
BMC Genomics ; 21(1): 637, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928113

RESUMO

Transcriptome sequencing has opened the field of genomics to a wide variety of researchers, owing to its efficiency, applicability across species and ability to quantify gene expression. The resulting datasets are a rich source of information that can be mined for many years into the future, with each dataset providing a unique angle on a specific context in biology. Maintaining accessibility to this accumulation of data presents quite a challenge for researchers.The primary focus of conventional genomics databases is the storage, navigation and interpretation of sequence data, which is typically classified down to the level of a species or individual. The addition of expression data adds a new dimension to this paradigm - the sampling context. Does gene expression describe different tissues, a temporal distribution or an experimental treatment? These data not only describe an individual, but the biological context surrounding that individual. The structure and utility of a transcriptome database must therefore reflect these attributes. We present an online database which has been designed to maximise the accessibility of crustacean transcriptome data by providing intuitive navigation within and between datasets and instant visualization of gene expression and protein structure.The site is accessible at https://crustybase.org and currently holds 10 datasets from a range of crustacean species. It also allows for upload of novel transcriptome datasets through a simple web interface, allowing the research community to contribute their own data to a pool of shared knowledge.


Assuntos
Crustáceos/genética , Bases de Dados Genéticas , Transcriptoma , Animais , Crustáceos/metabolismo , Software
12.
Gen Comp Endocrinol ; 294: 113496, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32360560

RESUMO

Neuropeptides are ancient endocrine components which have evolved to regulate many aspects of biology across the animal kingdom including behaviour, development and metabolism. To supplement current knowledge, we have utilized a transcriptome series describing larval development in the ornate spiny lobster, Panulirus ornatus. The biology of this animal has been leveraged to provide insights into the roles of molting, metamorphosis and metabolism across the neuropeptide family. We report an extensive list of neuropeptides across three distinct life phases of the animal. We show distinct groups of neuropeptides with differential expression between larval phases, indicating phase-specific roles for these peptides. For selected neuropeptides, we describe and discuss expression profiles throughout larval development and report predicted peptide cleavage sites and mature peptide sequences. We also report the neuropeptide nesfatin for the first time in a crustacean, and report secondary peptide products with a level of evolutionary conservation similar to the conventional mature peptide nesfatin-1, indicating a conserved role in these secondary products which are widely regarded as biologically inactive. In addition, we report a trend of downregulation in the neuropeptides as the animal undergoes extensive neural remodelling in fulfillment of metamorphosis. We suggest that this downregulation in neuropeptides relates to the brief, yet dramatic changes in morphology experienced by the central nervous system in the process of metamorphosis.


Assuntos
Neurônios/metabolismo , Neuropeptídeos/metabolismo , Palinuridae/metabolismo , Sequência de Aminoácidos , Animais , Larva/genética , Larva/metabolismo , Muda/genética , Neuropeptídeos/genética , Palinuridae/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética , Regulação para Cima/genética
13.
Proc Natl Acad Sci U S A ; 114(40): E8537-E8546, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923925

RESUMO

Seismic surveys map the seabed using intense, low-frequency sound signals that penetrate kilometers into the Earth's crust. Little is known regarding how invertebrates, including economically and ecologically important bivalves, are affected by exposure to seismic signals. In a series of field-based experiments, we investigate the impact of exposure to seismic surveys on scallops, using measurements of physiological and behavioral parameters to determine whether exposure may cause mass mortality or result in other sublethal effects. Exposure to seismic signals was found to significantly increase mortality, particularly over a chronic (months postexposure) time scale, though not beyond naturally occurring rates of mortality. Exposure did not elicit energetically expensive behaviors, but scallops showed significant changes in behavioral patterns during exposure, through a reduction in classic behaviors and demonstration of a nonclassic "flinch" response to air gun signals. Furthermore, scallops showed persistent alterations in recessing reflex behavior following exposure, with the rate of recessing increasing with repeated exposure. Hemolymph (blood analog) physiology showed a compromised capacity for homeostasis and potential immunodeficiency, as a range of hemolymph biochemistry parameters were altered and the density of circulating hemocytes (blood cell analog) was significantly reduced, with effects observed over acute (hours to days) and chronic (months) scales. The size of the air gun had no effect, but repeated exposure intensified responses. We postulate that the observed impacts resulted from high seabed ground accelerations driven by the air gun signal. Given the scope of physiological disruption, we conclude that seismic exposure can harm scallops.


Assuntos
Acústica , Comportamento Animal , Exposição Ambiental , Ruído , Pecten/fisiologia , Som , Estresse Fisiológico , Animais
14.
Int J Mol Sci ; 21(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971953

RESUMO

RNA interference (RNAi) has become a widely utilized method for studying gene function, yet despite this many of the mechanisms surrounding RNAi remain elusive. The core RNAi machinery is relatively well understood, however many of the systemic mechanisms, particularly double-stranded RNA (dsRNA) transport, are not. Here, we demonstrate that dsRNA binding proteins in the serum contribute to systemic RNAi and may be the limiting factor in RNAi capacity for species such as spiny lobsters, where gene silencing is not functional. Incubating sera from a variety of species across phyla with dsRNA led to a gel mobility shift in species in which systemic RNAi has been observed, with this response being absent in species in which systemic RNAi has never been observed. Proteomic analysis suggested lipoproteins may be responsible for this phenomenon and may transport dsRNA to spread the RNAi signal systemically. Following this, we identified the same gel shift in the slipper lobster Thenus australiensis and subsequently silenced the insulin androgenic gland hormone, marking the first time RNAi has been performed in any lobster species. These results pave the way for inducing RNAi in spiny lobsters and for a better understanding of the mechanisms of systemic RNAi in Crustacea, as well as across phyla.


Assuntos
Proteínas de Artrópodes , Palinuridae , Interferência de RNA , RNA de Cadeia Dupla , Proteínas de Ligação a RNA , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Humanos , Palinuridae/genética , Palinuridae/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
16.
BMC Genomics ; 20(1): 531, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253104

RESUMO

BACKGROUND: The Crustacea are an evolutionarily diverse taxon which underpins marine food webs and contributes significantly to the global economy. However, our knowledge of crustacean endocrinology and development is far behind that of terrestrial arthropods. Here we present a unique insight into the molecular pathways coordinating crustacean metamorphosis, by reconciling nuclear receptor (NR) gene activity from a 12-stage, 3-replicate transcriptome in the ornate spiny lobster (Panulirus ornatus) during larval development. RESULTS: We annotated 18 distinct nuclear receptor genes, including three novel NRs which are upregulated prior to metamorphosis and have hence been named the "molt-associated receptors" (MARs). We also demonstrate the ecdysone-responsive expression of several known molt-related NRs including ecdysone receptor, fushi-tarazu-F1 and E75. Phylogenetic analysis of the curated NR family confirmed gene annotations and suggested that the MARs are a recent addition to the crustacean superfamily, occurring across the Malacostraca from the Stomatopoda to the Decapoda. The ligand-binding domain of these receptors appears to be less conserved than that of typical group-1 NRs. Expression data from two other crustacean species was utilized to examine MAR expression. The Y-organ of the tropical land crab showed a decline in expression of all MARs from intermolt to post-molt. Tissue distributions showed gonad-enriched expression in the Eastern rock lobster and antennal gland-enriched expression in the tropical land crab, although expression was evident across most tissues. CONCLUSION: By mining transcriptome data, we have curated an extensive list of NR genes expressed during the metamorphic molts of P. ornatus, including three novel crustacean NRs which appear to play a role in the molting process. Divergence of the E-region of these new receptors indicates that they may have adopted a function that is unconventional for NRs. Based on expression patterns, we can confirm that a number of NRs play a role in the ecdysone cassette which regulates molting in crustaceans. This study describes in detail the molecular events surrounding crustacean molting and metamorphosis by taking advantage of the distinctive life history unique to achelatan crustaceans.


Assuntos
Perfilação da Expressão Gênica , Metamorfose Biológica/genética , Palinuridae/crescimento & desenvolvimento , Palinuridae/genética , Receptores Citoplasmáticos e Nucleares/genética , Animais , Muda/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
17.
Proc Biol Sci ; 286(1907): 20191424, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31337309

RESUMO

The effects of anthropogenic aquatic noise on marine invertebrates are poorly understood. We investigated the impact of seismic surveys on the righting reflex and statocyst morphology of the palinurid rock lobster, Jasus edwardsii, using field-based exposure to air gun signals. Following exposure equivalent to a full-scale commercial assay passing within 100-500 m, lobsters showed impaired righting and significant damage to the sensory hairs of the statocyst. Reflex impairment and statocyst damage persisted over the course of the experiments-up to 365 days post-exposure and did not improved following moulting. These results indicate that exposure to air gun signals caused morphological damage to the statocyst of rock lobsters, which can in turn impair complex reflexes. This damage and impairment adds further evidence that anthropogenic aquatic noise has the potential to harm invertebrates, necessitating a better understanding of possible ecological and economic impacts.


Assuntos
Ruído/efeitos adversos , Palinuridae/fisiologia , Acústica , Animais , Feminino , Armas de Fogo , Palinuridae/efeitos da radiação , Reflexo de Endireitamento/fisiologia , Reflexo de Endireitamento/efeitos da radiação , Órgãos dos Sentidos/fisiologia , Órgãos dos Sentidos/efeitos da radiação
18.
Fish Shellfish Immunol ; 89: 660-671, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30902723

RESUMO

Lobsters are fished world-wide due to their status as a high value, luxury seafood. A large proportion of the product is sold via live export, with lobsters subject to a range of stressors during holding post-capture. Improving the current understanding of the immune response to these stressors assists in improving efficiency and reducing loss in the chain between capture and consumption. In this study, the immune status of four treatment groups of Southern Rock Lobster (Jasus edwardsii) were studied: controls recently landed from a fishing boat, lobsters displaying advanced shell necrosis, lobsters in an unexplained moribund state and lobsters held in a processing facility for 10 weeks in standard conditions (i.e. high density, fasted). A total of 15 immune parameters and 19 haemolymph biochemical parameters were assayed. Phenoloxidase activity was only sporadically observed in haemocyte lysate and was consistently observed at a low level in the plasma with no difference between treatments for either. Haemocyte lysate prophenoloxidase activity was detected in most individuals, with no differences found between treatments. Prophenoloxidase in the plasma showed the highest level of activity, with the shell necrosis treatment demonstrating an elevated activity level relative to the other three treatments. Cell viability was not affected in any treatment. Lobsters with shell necrosis had a reduced capacity for phagocytosis, a significantly higher total haemocyte count, fewer hyalinocytes and more granulocytes and semigranulocytes. Fasted lobsters showed an opposite shift, with significantly more hyalinocytes compared to the other treatments and very few granulocytes and semigranulocytes. The balance of a range electrolytes, minerals metabolites and enzymes were affected in shell necrosis and fasted treatments, raising them as potential markers for immunocompromised lobsters. Multivariate analysis of all assayed parameters showed that all individuals in the necrosis treatment showed a similar, distinct immune response and that the fasted treatment, along with one control and one moribund individual, showed a separate intermediate response. The remainder of the control and moribund lobsters demonstrated a distinct "non-response" in comparison. These results offer a characterisation of the physiological response to common challenges during post-capture holding of rock lobsters, demonstrating the differential response to pathogenic bacterial infection, long term fasting, non-specific moribundity and the stress of capture and transport.


Assuntos
Hemócitos/enzimologia , Hemolinfa/química , Imunidade Inata , Palinuridae/imunologia , Animais , Feminino , Masculino , Estresse Fisiológico
19.
J Genet Couns ; 28(4): 869-877, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31058406

RESUMO

Genetic counseling careers continue to evolve, yet there remains a lack of information about hiring trends in the genetic counseling profession. In this study, job advertisements in the United States and Canada were analyzed, using the National Society of Genetic Counselors (NSGC) Job Connections and the American Board of Genetic Counseling (ABGC) eBlasts from 2014 to 2016 to appraise job roles, qualifications, settings, specialties, and type. NSGC had 1875 advertised openings from 2014 to 2016, while ABGC had 373 advertised openings. Jobs containing a "counseling" role increased as a percentage from 2014 to 2016 when advertised by NSGC (χ2  = 25.52, p < 0.000001) but decreased each year from 2014 to 2016 as a percentage when advertised through ABGC (χ2  = 14.29, p = 0.0008). In the ABGC job postings, it was noted that 36% of job postings were advertised for other specialties (not solely cancer, pediatric, or prenatal) in 2014, and increased to 67% in 2016 (χ2  = 10.09, p = 0.02). Examining the job specialties posted by ABGC and NSGC, several new or unique roles were found in the job advertisements such as ophthalmology counselor, variant curator, rare diseases information specialist, and clinical policy analyst. Roles for temporary, contract or fellowship positions are possibly becoming more common, along with small upturns in positions that are off-site or remote. In analyzing the changing workforce, there was a statistically significant decrease identified in jobs advertised by NSGC in the laboratory setting from 28% in 2014 to 17% in 2016 (χ2  = 24.12, p = 0.000024). This information on the evolving career of genetic counseling is valuable for the current workforce and training programs as they adapt with the changing landscape of the profession.


Assuntos
Publicidade , Aconselhamento Genético , Seleção de Pessoal , Canadá , Conselheiros , Humanos , Estudos Retrospectivos , Estados Unidos , Recursos Humanos
20.
Dev Biol ; 430(2): 337-345, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28864068

RESUMO

Sex determination pathways are extensively diverse across species, with the master sex-determinants being the most variable element. Despite this, there is a family of DM-domain transcription factors (Dmrts), which hold a highly conserved function in sexual development. This work is the first to describe a heterogametic sex-linked Dmrt in an invertebrate species, the Eastern spiny lobster, Sagmariasus verreauxi. We have termed the Y-linked, truncated paralogue of the autosomal iDmrt1, Sv-iDMY. Considering the master sex-determining function of both DMY in medaka and DM-W in frog, we hypothesised a similar function of Sv-iDMY. By conducting temporal expression analyses during embryogenesis we have identified a putative male sex-determining period during which iDMY>iDmrt1. Employing a GAL4-transactivation assay we then demonstrate the dominant negative suppression of iDMY over its autosomal iDmrt1 paralogue, suggesting the mechanism with which iDMY determines sex. Comparative analyses of Sv-iDMY, DM-W and medaka DMY, highlight the C'-mediated features of oligomerisation and transactivation as central to the mechanism that each exerts. Indeed, these features may underpin the plasticity facilitating the convergent emergence of these three sporadic sex-linked master-Dmrts.


Assuntos
Genes Ligados ao Cromossomo Y , Palinuridae/genética , Fatores de Transcrição/genética , Cromossomo Y/genética , Animais , Antenas de Artrópodes/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Oryzias/genética , Domínios Proteicos , Especificidade da Espécie , Testículo/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/fisiologia , Ativação Transcricional , Xenopus laevis/genética
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