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1.
PLoS One ; 19(4): e0302388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648207

RESUMO

The anadromous Atlantic salmon undergo a preparatory physiological transformation before seawater entry, referred to as smoltification. Key molecular developmental processes involved in this life stage transition, such as remodeling of gill functions, are known to be synchronized and modulated by environmental cues like photoperiod. However, little is known about the photoperiod influence and genome regulatory processes driving other canonical aspects of smoltification such as the large-scale changes in lipid metabolism and energy homeostasis in the developing smolt liver. Here we generate transcriptome, DNA methylation, and chromatin accessibility data from salmon livers across smoltification under different photoperiod regimes. We find a systematic reduction of expression levels of genes with a metabolic function, such as lipid metabolism, and increased expression of energy related genes such as oxidative phosphorylation, during smolt development in freshwater. However, in contrast to similar studies of the gill, smolt liver gene expression prior to seawater transfer was not impacted by photoperiodic history. Integrated analyses of gene expression, chromatin accessibility, and transcription factor (TF) binding signatures highlight chromatin remodeling and TF dynamics underlying smolt gene regulatory changes. Differential peak accessibility patterns largely matched differential gene expression patterns during smoltification and we infer that ZNF682, KLFs, and NFY TFs are important in driving a liver metabolic shift from synthesis to break down of organic compounds in freshwater. Overall, chromatin accessibility and TFBS occupancy were highly correlated to changes in gene expression. On the other hand, we identified numerous differential methylation patterns across the genome, but associated genes were not functionally enriched or correlated to observed gene expression changes across smolt development. Taken together, this work highlights the relative importance of chromatin remodeling during smoltification and demonstrates that metabolic remodeling occurs as a preadaptation to life at sea that is not to a large extent driven by photoperiod history.


Assuntos
Fígado , Salmo salar , Animais , Fígado/metabolismo , Salmo salar/genética , Salmo salar/crescimento & desenvolvimento , Salmo salar/metabolismo , Fotoperíodo , Metilação de DNA , Genoma , Transcriptoma , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Água do Mar , Metabolismo dos Lipídeos/genética , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo
2.
Proc Biol Sci ; 290(2009): 20231882, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37876191

RESUMO

The fossil record indicates a major turnover in marine phytoplankton across the Ediacaran-Cambrian transition, coincident with the rise of animal-rich ecosystems. However, the diversity, affinities and ecologies of Cambrian phytoplankton are poorly understood, leaving unclear the role of animal interactions and the drivers of diversification. New exceptionally preserved acritarchs (problematic organic-walled microfossils) from the late early Cambrian (around 510 Ma) reveal colonial organization characterized by rings and plates of interconnected, geometrically arranged cells. The assemblage exhibits a wide but gradational variation in cell size, ornamentation and intercell connection, interpreted as representing one or more species with determinate (coenobial) colony formation via cell division, aggregation and growth by cell expansion. An equivalent strategy is known only among green algae, specifically chlorophycean chlorophytes. The fossils differ in detail from modern freshwater examples and apparently represent an earlier convergent radiation in marine settings. Known trade-offs between sinking risk and predator avoidance in colonial phytoplankton point to adaptations triggered by intensifying grazing pressure during a Cambrian metazoan invasion of the water column. The new fossils reveal that not all small acritarchs are unicellular resting cysts, and support an early Palaeozoic prominence of green algal phytoplankton as predicted by molecular biomarkers.


Assuntos
Evolução Biológica , Clorófitas , Animais , Ecossistema , Plâncton , Ecologia , Fósseis , Fitoplâncton
3.
Front Public Health ; 11: 1057689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778554

RESUMO

As the number of older adults is growing rapidly in the U.S., the need for personalized, innovative, and sustainable Information and Communication Technologies (ICTs) solutions is critical to support individuals' social, emotional, and physical health. Such technology can significantly help older adults' ability to live independently in their homes despite the challenges the aging process may present, referred to as aging or staging in place. In this study, we explored ways to integrate ICTs into Agile Dwelling Units (AgDUs) through affordable, innovative, technology-enabled tools and practices that can be adapted to respond to individual's needs while supporting independent, secure, and engaged healthy living. The technology-enabled and human-centered AgDUs organically transform in response to users' needs. This approach offers a viable solution for older adults at different stages throughout their lifespan to transition into an intimate, technologically-enhanced living environment while allowing for (1) customization to user's needs; (2) cost optimization and maintenance; and (3) accessibility that minimizes gaps in compliance from a provider and user perspectives. Integrating ICTs in AgDUs to support health monitoring and management could reduce forthcoming pressure on the healthcare system and care providers to accommodate the needs of older adults. This approach is described through a collaborative multidisciplinary lens that highlights a partnership between academia, industry experts, and key stakeholders to advance healthy living and extend lifespan through design-build and technology integration. The main goal of this approach is to increase access to health services and optimize healthcare costs.


Assuntos
Envelhecimento , Atenção à Saúde , Humanos , Idoso , Envelhecimento/psicologia , Comunicação , Motivação , Longevidade
4.
G3 (Bethesda) ; 13(4)2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36786483

RESUMO

The expansion of genomic resources for Atlantic salmon over the past half decade has enabled efficient interrogation of genetic traits by large-scale correlation of genotype to phenotype. Moving from correlation to causation will require genotype-phenotype relationships to be tested experimentally in a cost-efficient and cell context-relevant manner. To enable such future experiments, we have developed a method for the isolation and genetic manipulation of primary hepatocytes from Atlantic salmon for use in heterologous expression, reporter assay, and gene editing experiments. We chose the liver as the tissue of interest because it is the metabolic hub and many current Atlantic salmon research projects focus on understanding metabolic processes to improve traits such as the growth rate, total fat content, and omega-3 content. We find that isolated primary hepatocytes are optimally transfected with both plasmid and ribonucleoprotein using a Neon electroporator at 1,400 V, 10 ms, and 2 pulses. Transfection efficiency with plasmid and cutting efficiency with ribonucleoprotein were optimally 46% and 60%, respectively. We also demonstrate a 26 times increase in luciferase expression under the promoter of the key liver metabolic gene, elovl5b, compared to an empty vector, in line with expected liver-specific expression. Taken together, this work provides a valuable resource enabling transfection and gene editing experiments in a context-relevant and cost-effective system.


Assuntos
Salmo salar , Animais , Salmo salar/genética , Edição de Genes , Transfecção , Hepatócitos , Regiões Promotoras Genéticas
5.
Biol Lett ; 17(12): 20210403, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34847752

RESUMO

The fossil record of terrestrialization documents notable shifts in the environmental and physiological tolerances of many animal and plant groups. However, for certain significant components of modern freshwater and terrestrial environments, the transition out of marine settings remains largely unconstrained. Ostracod crustaceans occupy an exceptional range of modern aquatic environments and are invaluable palaeoenvironmental indicators in the fossil record. However, pre-Carboniferous records of supposed non-marine and marginal marine ostracods are sparse, and the timing of their marine to non-marine transition has proven elusive. Here, we reassess the early environmental history of ostracods in light of new assemblages from the late Silurian of Vietnam. Two, low diversity but distinct ostracod assemblages are associated with estuarine deposits. This occurrence is consistent with previous incidental reports of ostracods occupying marginal and brackish settings through the late Silurian and Devonian. Therefore, ostracods were pioneering the occupation of marginal marine and estuarine settings 60 Myr before the Carboniferous and they were a component of the early phase of transition from marine to non-marine environments.


Assuntos
Crustáceos , Estuários , Animais , Fósseis , Água Doce , Plantas
6.
Nat Commun ; 12(1): 3868, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162853

RESUMO

Marine ecosystems with a diverse range of animal groups became established during the early Cambrian (~541 to ~509 Ma). However, Earth's environmental parameters and palaeogeography in this interval of major macro-evolutionary change remain poorly constrained. Here, we test contrasting hypotheses of continental configuration and climate that have profound implications for interpreting Cambrian environmental proxies. We integrate general circulation models and geological observations to test three variants of the 'Antarctocentric' paradigm, with a southern polar continent, and an 'equatorial' configuration that lacks polar continents. This quantitative framework can be applied to other deep-time intervals when environmental proxy data are scarce. Our results show that the Antarctocentric palaeogeographic paradigm can reconcile geological data and simulated Cambrian climate. Our analyses indicate a greenhouse climate during the Cambrian animal radiation, with mean annual sea-surface temperatures between ~9 °C to ~19 °C and ~30 °C to ~38 °C for polar and tropical palaeolatitudes, respectively.

7.
J Agric Food Chem ; 69(12): 3787-3796, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33754702

RESUMO

Salmon is an important source of long-chain highly unsaturated fatty acids (LC-HUFAs) such as 22:6n-3 [docosahexaenoic acid (DHA)]. In the present study, we conducted two identical experiments on salmon in freshwater (FW) and seawater (SW) stages, with a diet switch from fish oil (high in LC-HUFA) to vegetable oil (low in LC-HUFA) and vice versa. Our aim was to investigate the diet and life stage-specific features of lipid uptake (gut), processing (liver), and deposition (muscle). The lipid composition changed much faster in the gut of SW fish relative to FW fish, suggesting that the former had a higher rate of lipid absorption and transport. SW fish also had higher expression of phospholipid synthesis and lipoprotein formation genes in the gut, whereas FW fish had higher expression of lipid synthesis genes in the liver. All phospholipids except PC-44:12 and PE-44:12 were less abundant in SW, suggesting that SW fish have a higher requirement for DHA.


Assuntos
Salmo salar , Animais , Dieta/veterinária , Ácidos Graxos , Óleos de Peixe , Lipidômica , Óleos de Plantas
8.
J Patient Saf ; 17(3): e135-e142, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28157790

RESUMO

OBJECTIVES: The aim of this study was to identify physical design elements that contribute to potential falls in patient rooms. METHODS: An exploratory, physical simulation-based approach was adopted for the study. Twenty-seven subjects, older than 70 years (11 male and 16 female subjects), conducted scripted tasks in a mockup of a patient bathroom and clinician zone. Activities were captured using motion-capture technology and video recording. After biomechanical data processing, video clips associated with potential fall moments were extracted and then examined and coded by a group of registered nurses and health care designers. Exploratory analyses of the coded data were conducted followed by a series of multivariate analyses using regression models. RESULTS: In multivariate models with all personal, environmental, and postural variables, only the postural variables demonstrated statistical significance-turning, grabbing, pushing, and pulling in the bathroom and pushing and pulling in the clinician zone. The physical elements/attributes associated with the offending postures include bathroom configuration, intravenous pole, door, toilet seat height, flush, grab bars, over-bed table, and patient chair. CONCLUSIONS: Postural changes, during interactions with the physical environment, constitute the source of most fall events. Physical design must include simultaneous examination of postural changes in day-to-day activities in patient rooms and bathrooms. Among discussed testable recommendations in the article, the followings design strategies should be considered: (a) designing bathrooms to reduce turning as much as possible and (b) designing to avoid motions that involve 2 or more of the offending postures, such as turning and grabbing or grabbing and pulling, and so on.


Assuntos
Banheiros , Feminino , Humanos , Masculino , Gravação em Vídeo
9.
Genet Sel Evol ; 52(1): 66, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158415

RESUMO

BACKGROUND: One objective of this study was to identify putative quantitative trait loci (QTL) that affect indicator phenotypes for growth, nitrogen, and carbon metabolism in muscle, liver, and adipose tissue, and for feed efficiency. Another objective was to perform an RNAseq analysis (184 fish from all families), to identify genes that are associated with carbon and nitrogen metabolism in the liver. The material consisted of a family experiment that was performed in freshwater and included 2281 individuals from 23 full-sib families. During the 12-day feed conversion test, families were randomly allocated to family tanks (50 fish per tank and 2 tanks per family) and fed a fishmeal-based diet labeled with the stable isotopes 15N and 13C at inclusion levels of 2 and 1%, respectively. RESULTS: Using a linear mixed-model algorithm, a QTL for pre-smolt growth was identified on chromosome 9 and a QTL for carbon metabolism in the liver was identified on chromosome 12 that was closely related to feed conversion ratio on a tank level. For the indicators of feed efficiency traits that were derived from the stable isotope ratios (15N and 13C) of muscle tissue and growth, no convincing QTL was detected, which suggests that these traits are polygenic. The transcriptomic analysis showed that high carbon and nitrogen metabolism was associated with individuals that convert protein from the feed more efficiently, primarily due to higher expression of the proteasome, lipid, and carbon metabolic pathways in liver. In addition, we identified seven transcription factors that were associated with carbon and nitrogen metabolism and located in the identified QTL regions. CONCLUSIONS: Analyses revealed one QTL associated with pre-smolt growth and one QTL for carbon metabolism in the liver. Both of these traits are associated with feed efficiency. However, more accurate mapping of the putative QTL will require a more diverse family material. In this experiment, fish that have a high carbon and nitrogen metabolism in the liver converted protein from the feed more efficiently, potentially because of a higher expression of the proteasome, lipid, and carbon metabolic pathways in liver. Within the QTL regions, we detected seven transcription factors that were associated with carbon and nitrogen metabolism.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/genética , Locos de Características Quantitativas , Característica Quantitativa Herdável , Salmo salar/genética , Ração Animal , Animais , Carbono/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fígado/metabolismo , Herança Multifatorial , Músculo Esquelético/metabolismo , Nitrogênio/metabolismo , Salmo salar/crescimento & desenvolvimento , Salmo salar/metabolismo , Transdução de Sinais , Transcriptoma
10.
Commun Biol ; 3(1): 517, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948820

RESUMO

Here, we report the earliest fossil record to our knowledge of surface fouling by aggregates of small vermiform, encrusting and annulated tubular organisms associated with a mobile, nektonic host, the enigmatic Cambrian animal Vetulicola. Our material is from the exceptionally preserved early Cambrian (Epoch 2, Age 3), Chengjiang biota of Yunnan Province, southwest China, a circa 518 million-year old marine deposit. Our data show that symbiotic fouling relationships between species formed a component of the diversification of animal-rich ecosystems near the beginning of the Phanerozoic Eon, suggesting an early escalation of intimate ecologies as part of the Cambrian animal radiation.


Assuntos
Organismos Aquáticos/fisiologia , Evolução Biológica , Biota/fisiologia , Simbiose/fisiologia , Animais , Organismos Aquáticos/genética , Biota/genética , China/epidemiologia , Ecossistema , Fósseis , Paleontologia
11.
Opt Express ; 28(15): 21792-21804, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752451

RESUMO

A new nonlinear optical process, named enhanced stimulated Raman scattering (ESRS), is reported for the first time from resonance Raman in ß-carotene-methanol solution. It is well known that absorption decreases the efficiency of the nonlinear optical and laser processes; however, we observed enhanced stimulated Raman peaks at the first and second Stokes from methanol solvent at 2834 cm-1 with the addition of ß-carotene solutes. This enhanced SRS effect in methanol is attributed to the resonance Raman (RR) process in ß-carotene, which creates a significant number of vibrations from RR and the excess vibrations are transferred to methanol from anharmonic vibrational interactions between the ß-carotene solutes and the methanol solvent, and consequently leads to the increased Raman gain.

12.
Mol Ecol ; 29(10): 1860-1872, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32293070

RESUMO

Domestication of animals imposes strong targeted selection for desired traits but can also result in unintended selection due to new domestic environments. Atlantic salmon (Salmo salmar) was domesticated in the 1970s and has subsequently been selected for faster growth in systematic breeding programmes. More recently, salmon aquaculture has replaced fish oils (FOs) with vegetable oils (VOs) in feed, radically changing the levels of essential long-chain polyunsaturated fatty acids (LC-PUFAs). Our aim here was to study the impact of domestication on metabolism and explore the hypothesis that the shift to VO diets has unintentionally selected for a domestication-specific lipid metabolism. We conducted a 96-day feeding trial of domesticated and wild salmon fed diets based on FOs, VOs or phospholipids, and compared transcriptomes and fatty acids in tissues involved in lipid absorption (pyloric caeca) and lipid turnover and synthesis (liver). Domesticated salmon had faster growth and higher gene expression in glucose and lipid metabolism compared to wild fish, possibly linked to differences in regulation of circadian rhythm pathways. Only the domesticated salmon increased expression of LC-PUFA synthesis genes when given VOs. This transcriptome response difference was mirrored at the physiological level, with domesticated salmon having higher LC-PUFA levels but lower 18:3n-3 and 18:2n-6 levels. In line with this, the VO diet decreased growth rate in wild but not domesticated salmon. Our study revealed a clear impact of domestication on transcriptomic regulation linked to metabolism and suggests that unintentional selection in the domestic environment has resulted in evolution of stronger compensatory mechanisms to a diet low in LC-PUFAs.


Assuntos
Domesticação , Metabolismo dos Lipídeos , Salmo salar , Transcriptoma , Animais , Óleos de Peixe , Metabolismo dos Lipídeos/genética , Salmo salar/genética
13.
Biomolecules ; 10(2)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32023831

RESUMO

Fatty acid desaturase 2 (Fads2) is the key enzyme of long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis. Endogenous production of these biomolecules in vertebrates, if present, is insufficient to meet demand. Hence, LC-PUFA are considered as conditionally essential. At present, however, LC-PUFA are globally limited nutrients due to anthropogenic factors. Research attention has therefore been paid to finding ways to maximize endogenous LC-PUFA production, especially in production species, whereby deeper knowledge on molecular mechanisms of enzymatic steps involved is being generated. This review first briefly informs about the milestones in the history of LC-PUFA essentiality exploration before it focuses on the main aim-to highlight the fascinating Fads2 potential to play roles fundamental to adaptation to novel environmental conditions. Investigations are summarized to elucidate on the evolutionary history of fish Fads2, providing an explanation for the remarkable plasticity of this enzyme in fish. Furthermore, structural implications of Fads2 substrate specificity are discussed and some relevant studies performed on organisms other than fish are mentioned in cases when such studies have to date not been conducted on fish models. The importance of Fads2 in the context of growing aquaculture demand and dwindling LC-PUFA supply is depicted and a few remedies in the form of genetic engineering to improve endogenous production of these biomolecules are outlined.


Assuntos
Ácidos Graxos Dessaturases/química , Proteínas de Peixes/química , Peixes , Animais , Aquicultura , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/química , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Engenharia Genética , Inflamação , Filogenia , Relação Estrutura-Atividade , Especificidade por Substrato , Transgenes
14.
PLoS One ; 15(1): e0227404, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945087

RESUMO

BACKGROUND: Breast cancer is the fifth most prevalent cause of death among women worldwide. It is also one of the most common types of cancer among Malaysian women. This study aimed to characterize and differentiate the proteomics profiles of different stages of breast cancer and its matched adjacent normal tissues in Malaysian breast cancer patients. Also, this study aimed to construct a pertinent protein pathway involved in each stage of cancer. METHODS: In total, 80 samples of tumor and matched adjacent normal tissues were collected from breast cancer patients at Seberang Jaya Hospital (SJH) and Kepala Batas Hospital (KBH), both in Penang, Malaysia. The protein expression profiles of breast cancer and normal tissues were mapped by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The Gel-Eluted Liquid Fractionation Entrapment Electrophoresis (GELFREE) Technology System was used for the separation and fractionation of extracted proteins, which also were analyzed to maximize protein detection. The protein fractions were then analyzed by tandem mass spectrometry (LC-MS/MS) analysis using LC/MS LTQ-Orbitrap Fusion and Elite. This study identified the proteins contained within the tissue samples using de novo sequencing and database matching via PEAKS software. We performed two different pathway analyses, DAVID and STRING, in the sets of proteins from stage 2 and stage 3 breast cancer samples. The lists of molecules were generated by the REACTOME-FI plugin, part of the CYTOSCAPE tool, and linker nodes were added in order to generate a connected network. Then, pathway enrichment was obtained, and a graphical model was created to depict the participation of the input proteins as well as the linker nodes. RESULTS: This study identified 12 proteins that were detected in stage 2 tumor tissues, and 17 proteins that were detected in stage 3 tumor tissues, related to their normal counterparts. It also identified some proteins that were present in stage 2 but not stage 3 and vice versa. Based on these results, this study clarified unique proteins pathways involved in carcinogenesis within stage 2 and stage 3 breast cancers. CONCLUSIONS: This study provided some useful insights about the proteins associated with breast cancer carcinogenesis and could establish an important foundation for future cancer-related discoveries using differential proteomics profiling. Beyond protein identification, this study considered the interaction, function, network, signaling pathway, and protein pathway involved in each profile. These results suggest that knowledge of protein expression, especially in stage 2 and stage 3 breast cancer, can provide important clues that may enable the discovery of novel biomarkers in carcinogenesis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama , Carcinogênese/metabolismo , Carcinoma Ductal , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal/metabolismo , Carcinoma Ductal/patologia , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Malásia , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Proteoma/metabolismo , Proteômica , Espectrometria de Massas em Tandem
15.
PeerJ ; 7: e7732, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576253

RESUMO

Hepatic lipid metabolism is traditionally investigated in vitro using hepatocyte monocultures lacking the complex three-dimensional structure and interacting cell types essential liver function. Precision cut liver slice (PCLS) culture represents an alternative in vitro system, which benefits from retention of tissue architecture. Here, we present the first comprehensive evaluation of the PCLS method in fish (Atlantic salmon, Salmo salar L.) and validate it in the context of lipid metabolism using feeding trials, extensive transcriptomic data, and fatty acid measurements. We observe an initial period of post-slicing global transcriptome adjustment, which plateaued after 3 days in major metabolic pathways and stabilized through 9 days. PCLS fed alpha-linolenic acid (ALA) and insulin responded in a liver-like manner, increasing lipid biosynthesis gene expression. We identify interactions between insulin and ALA, where two PUFA biosynthesis genes that were induced by insulin or ALA alone, were highly down-regulated when insulin and ALA were combined. We also find that transcriptomic profiles of liver slices are exceedingly more similar to whole liver than hepatocyte monocultures, both for lipid metabolism and liver marker genes. PCLS culture opens new avenues for high throughput experimentation on the effect of "novel feed composition" and represent a promising new strategy for studying genotype-specific molecular features of metabolism.

16.
Commun Biol ; 2: 329, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508504

RESUMO

Traditionally, the origin and evolution of modern arthropod body plans has been revealed through increasing levels of appendage specialisation exhibited by Cambrian euarthropods. Here we show significant variation in limb morphologies and patterns of limb-tagmosis among three early Cambrian arthropod species conventionally assigned to the Bradoriida. These arthropods are recovered as a monophyletic stem-euarthropod group (and sister taxon to crown-group euarthropods, i.e. Chelicerata, Mandibulata and their extinct relatives), thus implying a radiation of stem-euarthropods where trends towards increasing appendage specialisation were explored convergently with other euarthropod groups. The alternative solution, where bradoriids are polyphyletic, representing several independent origins of a small, bivalved body plan in lineages from diverse regions of the euarthropod and mandibulate stems, is only marginally less parsimonious. The new data reveal a previously unknown disparity of body plans in stem-euarthropods and both solutions support remarkable evolutionary convergence, either of fundamental body plans or appendage specialization patterns.


Assuntos
Artrópodes/anatomia & histologia , Animais , Extremidades/anatomia & histologia , Extremidades/diagnóstico por imagem , Filogenia , Microtomografia por Raio-X
17.
Brain Res Bull ; 152: 63-73, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31301381

RESUMO

Cerebral hypoperfusion involved a reduction in cerebral blood flow, leading to neuronal dysfunction, microglial activation and white matter degeneration. The effects on the blood-brain barrier (BBB) however, have not been well-documented. Here, two-vessel occlusion model was adopted to mimic the condition of cerebral hypoperfusion in Sprague-Dawley rats. The BBB permeability to high and low molecular weight exogenous tracers i.e. Evans blue dye and sodium fluorescein respectively, showed marked extravasation of the Evans blue dye in the frontal cortex, posterior cortex and thalamus-midbrain at day 1 following induction of cerebral hypoperfusion. Transmission electron microscopy revealed brain endothelial cell and astrocyte damages including increased pinocytotic vesicles and formation of membrane invaginations in the endothelial cells, and swelling of the astrocytes' end-feet. Investigation on brain microvessel protein expressions using two-dimensional (2D) gel electrophoresis coupled with LC-MS/MS showed that proteins involved in mitochondrial energy metabolism, transcription regulation, cytoskeleton maintenance and signaling pathways were differently expressed. The expression of aconitate hydratase, heterogeneous nuclear ribonucleoprotein, enoyl Co-A hydratase and beta-synuclein were downregulated, while the opposite observed for calreticulin and enhancer of rudimentary homolog. These findings provide insights into the BBB molecular responses to cerebral hypoperfusion, which may assist development of future therapeutic strategies.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/ultraestrutura , Circulação Cerebrovascular/fisiologia , Animais , Astrócitos/metabolismo , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Isquemia Encefálica/metabolismo , Transtornos Cerebrovasculares/metabolismo , Transtornos Cerebrovasculares/fisiopatologia , Cromatografia Líquida , Eletroforese em Gel Bidimensional , Células Endoteliais/metabolismo , Masculino , Permeabilidade , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Espectrometria de Massas em Tandem
18.
Proc Biol Sci ; 285(1881)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29925613

RESUMO

Chancelloriids are an extinct group of spiny Cambrian animals of uncertain phylogenetic position. Despite their sponge-like body plan, their spines are unlike modern sponge spicules, but share several features with the sclerites of certain Cambrian bilaterians, notably halkieriids. However, a proposed homology of these 'coelosclerites' implies complex transitions in body plan evolution. A new species of chancelloriid, Allonnia nuda, from the lower Cambrian (Stage 3) Chengjiang Lagerstätte is distinguished by its large size and sparse spination, with modified apical sclerites surrounding an opening into the body cavity. The sclerite arrangement in A. nuda and certain other chancelloriids indicates that growth involved sclerite addition in a subapical region, thus maintaining distinct zones of body sclerites and apical sclerites. This pattern is not seen in halkieriids, but occurs in some modern calcarean sponges. With scleritome assembly consistent with a sponge affinity, and in the absence of cnidarian- or bilaterian-grade features, it is possible to interpret chancelloriids as sponges with an unusually robust outer epithelium, strict developmental control of body axis formation, distinctive spicule-like structures and, by implication, minute ostia too small to be resolved in fossils. In this light, chancelloriids may contribute to the emerging picture of high disparity among early sponges.


Assuntos
Evolução Biológica , Fósseis , Poríferos/crescimento & desenvolvimento , Animais , China , Fósseis/anatomia & histologia , Poríferos/anatomia & histologia
19.
J Transl Med ; 16(1): 175, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29940972

RESUMO

BACKGROUND: Lipid intermediates produced during triacylglycerols (TAGs) synthesis and lipolysis in adipocytes interfere with the intracellular insulin signaling pathway and development of insulin resistance. This study aims to compare TAG species and their fatty acid composition in adipose tissues from insulin sensitive (IS), insulin resistant (IR) and type 2 diabetes mellitus (T2DM) obese individuals. METHODS: Human subcutaneous and omental adipose tissue biopsies were obtained from 64 clinically characterized obese individuals during weight reduction surgery. TAGs were extracted from the adipose tissues using the Bligh and Dyer method, then were subjected to non-aqueous reverse phase ultra-high performance liquid chromatography and full scan mass spectrometry acquisition and data dependent MS/MS on LTQ dual cell linear ion trap. TAGs and their fatty acid contents were identified and compared between IS, IR and T2DM individuals and their levels were correlated with metabolic traits of participants and the adipogenic potential of preadipocyte cultures established from their adipose tissues. RESULTS: Data revealed 76 unique TAG species in adipose tissues identified based on their exact mass. Analysis of TAG levels revealed a number of TAGs that were significantly altered with disease progression including C46:4, C48:5, C48:4, C38:1, C50:3, C40:2, C56:3, C56:4, C56:7 and C58:7. Enrichment analysis revealed C12:0 fatty acid to be associated with TAGs least abundant in T2DM whereas C18:3 was found in both depleted and enriched TAGs in T2DM. Significant correlations of various adipose tissue-derived TAG species and metabolic traits were observed, including age and body mass index, systemic total cholesterol, TAGs, and interleukin-6 in addition to adipogenic potential of preadipocytes derived from the same adipose tissues. CONCLUSION: Pilot data suggest that adipose tissues from obese IR and T2DM individuals exhibit TAG-specific signatures that may contribute to their increased risk compared to their IS counterparts. Future experiments are warranted to investigate the functional relevance of these specific lipidomic profiles.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Obesidade/metabolismo , Triglicerídeos/metabolismo , Adulto , Análise Discriminante , Ácidos Graxos/metabolismo , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Peso Molecular , Omento/metabolismo , Gordura Subcutânea/metabolismo
20.
Sci Adv ; 4(5): eaar5690, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29750198

RESUMO

The oceans of the early Cambrian (~541 to 509 million years ago) were the setting for a marked diversification of animal life. However, sea temperatures-a key component of the early Cambrian marine environment-remain unconstrained, in part because of a substantial time gap in the stable oxygen isotope (δ18O) record before the evolution of euconodonts. We show that previously overlooked sources of fossil biogenic phosphate have the potential to fill this gap. Pristine phosphatic microfossils from the Comley Limestones, UK, yield a robust δ18O signature, suggesting sea surface temperatures of 20° to 25°C at high southern paleolatitudes (~65°S to 70°S) between ~514 and 509 million years ago. These sea temperatures are consistent with the distribution of coeval evaporite and calcrete deposits, peak continental weathering rates, and also our climate model simulations for this interval. Our results support an early Cambrian greenhouse climate comparable to those of the late Mesozoic and early Cenozoic, offering a framework for exploring the interplay between biotic and environmental controls on Cambrian animal diversification.


Assuntos
Clima , Efeito Estufa , Biodiversidade , Ecossistema , Fósseis , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , História Antiga , Oceanos e Mares , Isótopos de Oxigênio/análise , Paleontologia , Temperatura
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