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1.
Metabolomics ; 20(4): 66, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886248

RESUMO

The coral holobiont is underpinned by complex metabolic exchanges between different symbiotic partners, which are impacted by environmental stressors. The chemical diversity of the compounds produced by the holobiont is high and includes primary and secondary metabolites, as well as volatiles. However, metabolites and volatiles have only been characterised in isolation so far. Here, we applied a paired metabolomic-volatilomic approach to characterise holistically the chemical response of the holobiont under stress. Montipora mollis fragments were subjected to high-light stress (8-fold higher than the controls) for 30 min. Photosystem II (PSII) photochemical efficiency values were 7-fold higher in control versus treatment corals immediately following high-light exposure, but returned to pre-stress levels after 30 min of recovery. Under high-light stress, we identified an increase in carbohydrates (> 5-fold increase in arabinose and fructose) and saturated fatty acids (7-fold increase in myristic and oleic acid), together with a decrease in fatty acid derivatives in both metabolites and volatiles (e.g., 80% decrease in oleamide and nonanal), and other antioxidants (~ 85% decrease in sorbitol and galactitol). These changes suggest short-term light stress induces oxidative stress. Correlation analysis between volatiles and metabolites identified positive links between sorbitol, galactitol, six other metabolites and 11 volatiles, with four of these compounds previously identified as antioxidants. This suggests that these 19 compounds may be related and share similar functions. Taken together, our findings demonstrate how paired metabolomics-volatilomics may illuminate broader metabolic shifts occurring under stress and identify linkages between uncharacterised compounds to putatively determine their functions.


Assuntos
Antozoários , Luz , Metabolômica , Estresse Fisiológico , Animais , Antozoários/metabolismo , Metabolômica/métodos , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Complexo de Proteína do Fotossistema II/metabolismo
2.
Cryobiology ; 116: 104909, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38763350

RESUMO

We studied the impact of modulating cholesterol levels in zebrafish sperm plasma membranes using cholesterol-loaded methyl-ß-cyclodextrin (CLC) and unloaded methyl-ß-cyclodextrin (MßC). Zebrafish sperm were treated with these substances before cryopreservation, and post-thaw sperm motility and in vitro fertilization (IVF) rates were compared between treated and untreated samples. Our findings indicate that adding cholesterol to sperm membranes increases post-thaw motility, motile cell count, and motile cell survival within a 0.5-4.0 mg per 1.2 × 108 cell concentration range. Conversely, depleting cholesterol using MßC at 1.0 and 2.0 mg per 1.2 × 108 cells reduced these parameters. On average, all CLC-treated sperm samples produced a 15 % higher IVF rate compared to untreated sperm. Including CLC in the extender before cryopreservation is beneficial for post-thaw sperm quantity and quality in zebrafish.

3.
Proc Biol Sci ; 290(1992): 20221877, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36750192

RESUMO

Anthropogenic stressors continue to escalate worldwide, driving unprecedented declines in reef environmental conditions and coral health. One approach to better understand how corals can function in the future is to examine coral populations that thrive within present day naturally extreme habitats. We applied untargeted metabolomics (gas chromatography-mass spectrometry (GC-MS)) to contrast metabolite profiles of Pocillopora acuta colonies from hot, acidic and deoxygenated mangrove environments versus those from adjacent reefs. Under ambient temperatures, P. acuta predominantly associated with endosymbionts of the genera Cladocopium (reef) or Durusdinium (mangrove), exhibiting elevated metabolism in mangrove through energy-generating and biosynthesis pathways compared to reef populations. Under transient heat stress, P. acuta endosymbiont associations were unchanged. Reef corals bleached and exhibited extensive shifts in symbiont metabolic profiles (whereas host metabolite profiles were unchanged). By contrast, mangrove populations did not bleach and solely the host metabolite profiles were altered, including cellular responses in inter-partner signalling, antioxidant capacity and energy storage. Thus mangrove P. acuta populations resist periodically high-temperature exposure via association with thermally tolerant endosymbionts coupled with host metabolic plasticity. Our findings highlight specific metabolites that may be biomarkers of heat tolerance, providing novel insight into adaptive coral resilience to elevated temperatures.


Assuntos
Antozoários , Dinoflagellida , Termotolerância , Animais , Antozoários/fisiologia , Recifes de Corais , Simbiose , Resposta ao Choque Térmico , Dinoflagellida/fisiologia
4.
Cryobiology ; 104: 70-78, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728226

RESUMO

The goal of this study was to investigate whether supplementation of cryoprotective medium with catalase (CAT), an antioxidation enzyme, is efficient for zebrafish sperm cryopreservation from the viewpoint of high-throughput genetic repository operations. Three cryoprotectants (10%, v/v), dimethylacetamide (DMA), dimethylformamide (DMF), and methanol were used. The objectives were to evaluate the effects of CAT on sperm motility, plasma membrane integrity, and concentration for: 1) fresh sperm at equilibration up to 60 min; 2) post-thaw sperm after cooling at 10, 20, and 40 °C/min), and 3) post-thaw fertilization and embryo survival rates. Catalase addition did not improve sperm motility, regardless of the cryoprotectants added. After 10-min exposure to DMA or methanol, membrane integrity was significantly decreased (70-75%) compared to controls. With catalase, sperm cells maintained membrane integrity and after 50 min equilibration, cell concentrations were maintained with CAT compared to cryoprotectant-only test groups. However, after cryopreservation and thawing, CAT did not affect the outcome of motility, membrane integrity, cell concentration, fertilization, or embryo survival assays. Analysis of cooling rates also indicated that CAT did not affect 3-hpf fertilization or 24-hpf survival rates. Overall, addition of CAT could provide some protection of sperm from oxidative stress before freezing, but not after thawing. We propose that decisions concerning routine use of CAT for repositories, especially those handling tens of thousands of frozen samples per year, would depend on whether efficient high-throughput operation, or specific research questions are programmatic goals.


Assuntos
Criopreservação , Preservação do Sêmen , Animais , Catalase/metabolismo , Criopreservação/métodos , Crioprotetores/metabolismo , Crioprotetores/farmacologia , Masculino , Metanol/farmacologia , Estresse Oxidativo , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Peixe-Zebra
5.
Environ Microbiol ; 22(5): 1675-1687, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31943674

RESUMO

The intimate relationship between scleractinian corals and their associated microorganisms is fundamental to healthy coral reef ecosystems. Coral-associated microbes (Symbiodiniaceae and other protists, bacteria, archaea, fungi and viruses) support coral health and resilience through metabolite transfer, inter-partner signalling, and genetic exchange. However, much of our understanding of the coral holobiont relationship has come from studies that have investigated either coral-Symbiodiniaceae or coral-bacteria interactions in isolation, while relatively little research has focused on other ecological and metabolic interactions potentially occurring within the coral multi-partner symbiotic network. Recent evidences of intimate coupling between phytoplankton and bacteria have demonstrated that obligate resource exchange between partners fundamentally drives their ecological success. Here, we posit that similar associations with bacterial consortia regulate Symbiodiniaceae productivity and are in turn central to the health of corals. Indeed, we propose that this bacteria-Symbiodiniaceae-coral relationship underpins the coral holobiont's nutrition, stress tolerance and potentially influences the future survival of coral reef ecosystems under changing environmental conditions. Resolving Symbiodiniaceae-bacteria associations is therefore a logical next step towards understanding the complex multi-partner interactions occurring in the coral holobiont.


Assuntos
Antozoários/microbiologia , Archaea/metabolismo , Bactérias/metabolismo , Dinoflagellida/microbiologia , Fungos/metabolismo , Simbiose/fisiologia , Animais , Bactérias/genética , Recifes de Corais , Ecossistema , Fungos/genética , Redes e Vias Metabólicas
6.
Proc Natl Acad Sci U S A ; 114(50): 13194-13199, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29158383

RESUMO

The relationship between corals and dinoflagellates of the genus Symbiodinium is fundamental to the functioning of coral ecosystems. It has been suggested that reef corals may adapt to climate change by changing their dominant symbiont type to a more thermally tolerant one, although the capacity for such a shift is potentially hindered by the compatibility of different host-symbiont pairings. Here we combined transcriptomic and metabolomic analyses to characterize the molecular, cellular, and physiological processes that underlie this compatibility, with a particular focus on Symbiodinium trenchii, an opportunistic, thermally tolerant symbiont that flourishes in coral tissues after bleaching events. Symbiont-free individuals of the sea anemone Exaiptasia pallida (commonly referred to as Aiptasia), an established model system for the study of the cnidarian-dinoflagellate symbiosis, were colonized with the "normal" (homologous) symbiont Symbiodinium minutum and the heterologous S. trenchii Analysis of the host gene and metabolite expression profiles revealed that heterologous symbionts induced an expression pattern intermediate between the typical symbiotic state and the aposymbiotic state. Furthermore, integrated pathway analysis revealed that increased catabolism of fixed carbon stores, metabolic signaling, and immune processes occurred in response to the heterologous symbiont type. Our data suggest that both nutritional provisioning and the immune response induced by the foreign "invader" are important factors in determining the capacity of corals to adapt to climate change through the establishment of novel symbioses.


Assuntos
Dinoflagellida/genética , Anêmonas-do-Mar/genética , Simbiose/genética , Animais , Recifes de Corais , Dinoflagellida/metabolismo , Dinoflagellida/fisiologia , Metaboloma , Estresse Oxidativo , Anêmonas-do-Mar/metabolismo , Anêmonas-do-Mar/fisiologia , Simbiose/imunologia , Transcriptoma
7.
Proc Biol Sci ; 285(1892)2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30487315

RESUMO

Metabolite exchange is fundamental to the viability of the cnidarian-Symbiodiniaceae symbiosis and survival of coral reefs. Coral holobiont tolerance to environmental change might be achieved through changes in Symbiodiniaceae species composition, but differences in the metabolites supplied by different Symbiodiniaceae species could influence holobiont fitness. Using 13C stable-isotope labelling coupled to gas chromatography-mass spectrometry, we characterized newly fixed carbon fate in the model cnidarian Exaiptasia pallida (Aiptasia) when experimentally colonized with either native Breviolum minutum or non-native Durusdinium trenchii Relative to anemones containing B. minutum, D. trenchii-colonized hosts exhibited a 4.5-fold reduction in 13C-labelled glucose and reduced abundance and diversity of 13C-labelled carbohydrates and lipogenesis precursors, indicating symbiont species-specific modifications to carbohydrate availability and lipid storage. Mapping carbon fate also revealed significant alterations to host molecular signalling pathways. In particular, D. trenchii-colonized hosts exhibited a 40-fold reduction in 13C-labelled scyllo-inositol, a potential interpartner signalling molecule in symbiosis specificity. 13C-labelling also highlighted differential antioxidant- and ammonium-producing pathway activities, suggesting physiological responses to different symbiont species. Such differences in symbiont metabolite contribution and host utilization may limit the proliferation of stress-driven symbioses; this contributes valuable information towards future scenarios that select in favour of less-competent symbionts in response to environmental change.


Assuntos
Dinoflagellida/fisiologia , Metabolismo Energético , Anêmonas-do-Mar/fisiologia , Simbiose , Animais
8.
J Exp Biol ; 219(Pt 3): 306-10, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26596538

RESUMO

Experimental manipulation of the symbiosis between cnidarians and photosynthetic dinoflagellates (Symbiodinium spp.) is crucial to advancing the understanding of the cellular mechanisms involved in host-symbiont interactions, and overall coral reef ecology. The anemone Aiptasia sp. is a model for cnidarian-dinoflagellate symbiosis, and notably it can be rendered aposymbiotic (i.e. dinoflagellate-free) and re-infected with a range of Symbiodinium types. Various methods exist for generating aposymbiotic hosts; however, they can be hugely time consuming and not wholly effective. Here, we optimise a method using menthol for production of aposymbiotic Aiptasia. The menthol treatment produced aposymbiotic hosts within just 4 weeks (97-100% symbiont loss), and the condition was maintained long after treatment when anemones were held under a standard light:dark cycle. The ability of Aiptasia to form a stable symbiosis appeared to be unaffected by menthol exposure, as demonstrated by successful re-establishment of the symbiosis when anemones were experimentally re-infected. Furthermore, there was no significant impact on photosynthetic or respiratory performance of re-infected anemones.


Assuntos
Dinoflagellida/efeitos dos fármacos , Mentol/farmacologia , Fisiologia/métodos , Anêmonas-do-Mar/fisiologia , Simbiose/efeitos dos fármacos , Animais , Recifes de Corais , Dinoflagellida/fisiologia , Fotossíntese
9.
Ann Plast Surg ; 77(1): 25-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25003435

RESUMO

BACKGROUND: The vertical scar bilateral breast reduction is a highly effective technique to reduce breast volume and create long-lasting aesthetic improvements. A cited disadvantage is the inability to adequately shorten the vertical scar, leading to chest wall scars or inframammary puckers. Gathering or cinching sutures have been described as a strategy to confront this issue. This article aims to determine if suture gathering is an effective methods to (1) reduce the incision length, (2) shorten the areola-to-inframammary fold (IMF) distance, and (3) reduce the pucker revision rate. METHODS: All patients undergoing vertical breast reduction performed by the senior author (E.H.F.) from 2001 to 2007 were included. The patient population was divided into "gather" and "no gather" groups depending on how the vertical incision was closed. RESULTS: There were 203 patients in the "no gather" group and 193 in the "gather" group. Age, body mass index, and resection weight were statistically but not clinically different. The percent reduction in vertical incision length was significantly greater in the "gather" group (34.2 ± 9.9% vs. 12.2 ± 5.9%). Both groups showed a gradual lengthening of areola-to-IMF distance postoperatively. Suture gathering had no impact on the pucker revision rate but increased healing complications. CONCLUSION: Gathering sutures significantly reduce the incision length in the operating room but do not change the areola-to-IMF distance or pucker revision rate. Gathering negatively influences skin vascularity and wound healing. It is acceptable and necessary to have a longer areola-to-IMF distance in a vertical reduction to accommodate increased projection.


Assuntos
Cicatriz/prevenção & controle , Mamoplastia/métodos , Complicações Pós-Operatórias/prevenção & controle , Técnicas de Sutura , Adulto , Cicatriz/etiologia , Cicatriz/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Cicatrização
10.
Cleft Palate Craniofac J ; 52(4): 417-24, 2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-25007034

RESUMO

OBJECTIVE: To examine the birth prevalence, gender distribution, and pattern of surgical intervention for clefts in Canada (1998 to 2007). Also to highlight the difficulties associated with studying the epidemiology of clefts using the current data collection mechanisms. METHODS: Epidemiologic data acquired from the Canadian Institute for Health Information. SETTING: Population-based study in Canada 1998 to 2007. PATIENTS: All live births with an International Classification of Diseases (9th or 10th revision) diagnostic code for cleft palate or for cleft lip with or without cleft palate or with a surgical intervention code for repair of cleft lip or cleft palate. MAIN OUTCOME MEASURES: Birth prevalence, gender distribution, and pattern of surgical intervention. RESULTS: There were 3,015,325 live births in Canada (1998 to 2007). The mean birth prevalence was 0.82 per 1000 live births for cleft lip with or without cleft palate and 0.58 per 1000 live births for cleft palate. The birth prevalence of cleft lip with or without cleft palate was significantly higher in boys, with a stable boy to girl ratio of 1.75:1. Cleft palate was significantly greater in girls; however, the boy to girl ratio decreased from 0.97:1 in 1998 to 0.59:1 in 2007. The median age of repair in Canada from 1998 to 2007 was 4.7 months for cleft lip and 11.6 months for cleft palate. Thirty percent of patients underwent cleft palate repair after age 1. CONCLUSION: The birth prevalence of cleft palate and cleft lip with or without cleft palate is stable in Canada. An increasing birth prevalence of cleft palate in girls is suggested. The timing of surgical intervention is consistent with current standards. The challenges associated with collecting these data in Canada are discussed.


Assuntos
Fenda Labial/epidemiologia , Fissura Palatina/epidemiologia , Canadá/epidemiologia , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Feminino , Humanos , Recém-Nascido , Masculino , Prevalência
11.
Microorganisms ; 12(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38399721

RESUMO

The urgency of responding to climate change for corals necessitates the exploration of innovative methods to swiftly enhance our understanding of crucial processes. In this study, we employ an integrated chemical omics approach, combining elementomics, metabolomics, and volatilomics methodologies to unravel the biochemical pathways associated with the thermal response of the coral symbiont, Symbiodiniaceae Durusdinium trenchii. We outline the complimentary sampling approaches and discuss the standardised data corrections used to allow data integration and comparability. Our findings highlight the efficacy of individual methods in discerning differences in the biochemical response of D. trenchii under both control and stress-inducing temperatures. However, a deeper insight emerges when these methods are integrated, offering a more comprehensive understanding, particularly regarding oxidative stress pathways. Employing correlation network analysis enhanced the interpretation of volatile data, shedding light on the potential metabolic origins of volatiles with undescribed functions and presenting promising candidates for further exploration. Elementomics proves to be less straightforward to integrate, likely due to no net change in elements but rather elements being repurposed across compounds. The independent and integrated data from this study informs future omic profiling studies and recommends candidates for targeted research beyond Symbiodiniaceae biology. This study highlights the pivotal role of omic integration in advancing our knowledge, addressing critical gaps, and guiding future research directions in the context of climate change and coral reef preservation.

12.
J Vis Exp ; (200)2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37902324

RESUMO

Gas chromatography-mass spectrometry (GC-MS)-based approaches have proven to be powerful for elucidating the metabolic basis of the cnidarian-dinoflagellate symbiosis and how coral responds to stress (i.e., during temperature-induced bleaching). Steady-state metabolite profiling of the coral holobiont, which comprises the cnidarian host and its associated microbes (Symbiodiniaceae and other protists, bacteria, archaea, fungi, and viruses), has been successfully applied under ambient and stress conditions to characterize the holistic metabolic status of the coral. However, to answer questions surrounding the symbiotic interactions, it is necessary to analyze the metabolite profiles of the coral host and its algal symbionts independently, which can only be achieved by physical separation and isolation of the tissues, followed by independent extraction and analysis. While the application of metabolomics is relatively new to the coral field, the sustained efforts of research groups have resulted in the development of robust methods for analyzing metabolites in corals, including the separation of the coral host tissue and algal symbionts. This paper presents a step-by-step guide for holobiont separation and the extraction of metabolites for GC-MS analysis, including key optimization steps for consideration. We demonstrate how, once analyzed independently, the combined metabolite profile of the two fractions (coral and Symbiodiniaceae) is similar to the profile of the whole (holobiont), but by separating the tissues, we can also obtain key information about the metabolism of and interactions between the two partners that cannot be obtained from the whole alone.


Assuntos
Antozoários , Animais , Antozoários/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica/métodos , Bactérias , Temperatura , Simbiose , Recifes de Corais
13.
JAMA Otolaryngol Head Neck Surg ; 149(9): 796-802, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37471080

RESUMO

Importance: Head and neck oncological resection and reconstruction is a complex process that requires multidisciplinary collaboration and prolonged operative time. Numerous factors are associated with operative time, including a surgeon's experience, team familiarity, and the use of new technologies. It is paramount to evaluate the contribution of these factors and modalities on operative time to facilitate broad adoption of the most effective modalities and reduce complications associated with prolonged operative time. Objective: To examine the association of head and neck cancer resection and reconstruction interventions with operative time. Design, Setting, and Participants: This large cohort study included all patients who underwent head and neck oncologic resection and free flap-based reconstruction in Calgary (Alberta, Canada) between January 1, 2007, and March 31, 2020. Data were analyzed between November 2021 and May2022. Interventions: The interventions that were implemented in the program were classified into team-based strategies and the introduction of new technology. Team-based strategies included introducing a standardized operative team, treatment centralization in a single institution, and introducing a microsurgery fellowship program. New technologies included use of venous coupler anastomosis and virtual surgical planning. Main Outcomes and Measures: The primary outcome was mean operative time difference before and after the implementation of each modality. Secondary outcomes included returns to the operating room within 30 days, reasons for reoperation, returns to the emergency department or readmissions to hospital within 30 days, and 2-year and 5-year disease-specific survival. Multivariate regression analyses were performed to examine the association of each modality with operative time. Results: A total of 578 patients (179 women [30.9%]; mean [SD] age, 60.8 [12.9] years) undergoing 590 procedures met inclusion criteria. During the study period, operative time progressively decreased and reached a 32% reduction during the final years of the study. A significant reduction was observed in mean operative time following the introduction of each intervention. However, a multivariate analysis revealed that team-based strategies, including the use of a standardized nursing team, treatment centralization, and a fellowship program, were significantly associated with a reduction in operative time. Conclusions: The results of this cohort study suggest that among patients with head and neck cancer, use of team-based strategies was associated with significant decreases in operative time without an increase in complications.


Assuntos
Retalhos de Tecido Biológico , Neoplasias de Cabeça e Pescoço , Humanos , Feminino , Pessoa de Meia-Idade , Estudos de Coortes , Estudos Retrospectivos , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias de Cabeça e Pescoço/complicações
14.
Nat Commun ; 14(1): 6864, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891154

RESUMO

Bacteria are key contributors to microalgae resource acquisition, competitive performance, and functional diversity, but their potential metabolic interactions with coral microalgal endosymbionts (Symbiodiniaceae) have been largely overlooked. Here, we show that altering the bacterial composition of two widespread Symbiodiniaceae species, during their free-living stage, results in a significant shift in their cellular metabolism. Indeed, the abundance of monosaccharides and the key phytohormone indole-3-acetic acid (IAA) were correlated with the presence of specific bacteria, including members of the Labrenzia (Roseibium) and Marinobacter genera. Single-cell stable isotope tracking revealed that these two bacterial genera are involved in reciprocal exchanges of carbon and nitrogen with Symbiodiniaceae. We identified the provision of IAA by Labrenzia and Marinobacter, and this metabolite caused a significant growth enhancement of Symbiodiniaceae. By unravelling these interkingdom interactions, our work demonstrates how specific bacterial associates fundamentally govern Symbiodiniaceae fitness.


Assuntos
Antozoários , Dinoflagellida , Rhodobacteraceae , Animais , Antozoários/microbiologia , Reguladores de Crescimento de Plantas , Recifes de Corais , Simbiose
15.
Sci Rep ; 13(1): 20724, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007500

RESUMO

Symbiodiniaceae form associations with extra- and intracellular bacterial symbionts, both in culture and in symbiosis with corals. Bacterial associates can regulate Symbiodiniaceae fitness in terms of growth, calcification and photophysiology. However, the influence of these bacteria on interactive stressors, such as temperature and light, which are known to influence Symbiodiniaceae physiology, remains unclear. Here, we examined the photophysiological response of two Symbiodiniaceae species (Symbiodinium microadriaticum and Breviolum minutum) cultured under acute temperature and light stress with specific bacterial partners from their microbiome (Labrenzia (Roseibium) alexandrii, Marinobacter adhaerens or Muricauda aquimarina). Overall, bacterial presence positively impacted Symbiodiniaceae core photosynthetic health (photosystem II [PSII] quantum yield) and photoprotective capacity (non-photochemical quenching; NPQ) compared to cultures with all extracellular bacteria removed, although specific benefits were variable across Symbiodiniaceae genera and growth phase. Symbiodiniaceae co-cultured with M. aquimarina displayed an inverse NPQ response under high temperatures and light, and those with L. alexandrii demonstrated a lowered threshold for induction of NPQ, potentially through the provision of antioxidant compounds such as zeaxanthin (produced by Muricauda spp.) and dimethylsulfoniopropionate (DMSP; produced by this strain of L. alexandrii). Our co-culture approach empirically demonstrates the benefits bacteria can deliver to Symbiodiniaceae photochemical performance, providing evidence that bacterial associates can play important functional roles for Symbiodiniaceae.


Assuntos
Antozoários , Dinoflagellida , Animais , Antozoários/fisiologia , Fotossíntese , Temperatura , Bactérias , Complexo de Proteína do Fotossistema II , Dinoflagellida/fisiologia , Simbiose
16.
Zebrafish ; 19(6): 241-244, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36318811

RESUMO

Severely skewed sex ratios in zebrafish stocks can pose significant hurdles for line propagation and sperm cryopreservation. To overcome female-biased sex ratios in stocks derived from imported sperm samples, the Zebrafish International Resource Center has implemented routine supplementation of larval food with 17α-methyltestosterone to skew gonadal sex differentiation toward masculinization. Resulting stocks averaged 80% males.


Assuntos
Metiltestosterona , Peixe-Zebra , Masculino , Feminino , Animais , Metiltestosterona/farmacologia , Sêmen , Gônadas , Diferenciação Sexual
17.
Methods Mol Biol ; 2218: 99-115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606226

RESUMO

Cryopreservation of sperm cells is currently the most efficient tool for managing large and small collections of valuable genetic resources. Cryopreservation minimizes expenses for animal and facility maintenance such as personnel, water, power, and space. It extends the time offspring can be produced from individual organisms, reduces the need to maintain live populations, provides flexibility for planning future experiments and research projects, and can prevent catastrophic loss of irreplaceable research lines. In this chapter, we present the sperm collection, dilution, cryopreservation, thawing, and in vitro fertilization procedures used at the Zebrafish International Resource Center (ZIRC).


Assuntos
Criopreservação/métodos , Preservação do Sêmen/métodos , Espermatozoides/citologia , Animais , Crioprotetores/farmacologia , Fertilização in vitro/métodos , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Peixe-Zebra/fisiologia
18.
Front Microbiol ; 12: 756091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759906

RESUMO

It has been proposed that an effective approach for predicting whether and how reef-forming corals persist under future climate change is to examine populations thriving in present day extreme environments, such as mangrove lagoons, where water temperatures can exceed those of reef environments by more than 3°C, pH levels are more acidic (pH < 7.9, often below 7.6) and O2 concentrations are regularly considered hypoxic (<2 mg/L). Defining the physiological features of these "extreme" corals, as well as their relationships with the, often symbiotic, organisms within their microbiome, could increase our understanding of how corals will persist into the future. To better understand coral-microbe relationships that potentially underpin coral persistence within extreme mangrove environments, we therefore conducted a 9-month reciprocal transplant experiment, whereby specimens of the coral Pocillopora acuta were transplanted between adjacent mangrove and reef sites on the northern Great Barrier Reef. Bacterial communities associated with P. acuta specimens native to the reef environment were dominated by Endozoicomonas, while Symbiodiniaceae communities were dominated by members of the Cladocopium genus. In contrast, P. acuta colonies native to the mangrove site exhibited highly diverse bacterial communities with no dominating members, and Symbiodiniaceae communities dominated by Durusdinium. All corals survived for 9 months after being transplanted from reef-to-mangrove, mangrove-to-reef environments (as well as control within environment transplants), and during this time there were significant changes in the bacterial communities, but not in the Symbiodiniaceae communities or their photo-physiological functioning. In reef-to-mangrove transplanted corals, there were varied, but sometimes rapid shifts in the associated bacterial communities, including a loss of "core" bacterial members after 9 months where coral bacterial communities began to resemble those of the native mangrove corals. Bacterial communities associated with mangrove-to-reef P. acuta colonies also changed from their original composition, but remained different to the native reef corals. Our data demonstrates that P. acuta associated bacterial communities are strongly influenced by changes in environmental conditions, whereas Symbiodiniaceae associated communities remain highly stable.

19.
Plast Reconstr Surg ; 148(6): 1007e-1011e, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847130

RESUMO

SUMMARY: Patient-reported outcomes regarding donor-site morbidity and quality of life for the fibula free flap in head and neck reconstruction patients have not been studied. The authors reviewed and identified patients who had undergone head and neck reconstruction using a fibula free flap (2011 to 2016). Patients were assessed via physical examination and two patient-reported outcomes questionnaires: the Foot and Ankle Outcome Score (score range, 0 to 100) and the Pain Disability Questionnaire (score range, 0 to 100). Quantitative data were analyzed with appropriate statistical tests. Semistructured interviews exploring donor-site challenges were performed and analyzed using thematic analysis. Seventeen patients agreed to participate. Their mean age was 62 years (range, 41 to 81 years). Mean follow-up was 38 months (range, 12 to 65 years). Mean perceived level of function compared to baseline was 67 percent. Mean scores for the Foot and Ankle Outcome Score subscales were 84.6 (pain), 80.5 (symptoms), 86.7 (activities of daily living), 67.7 (sport), and 65.6 (quality of life). The mean Pain Disability Questionnaire score was 26.3 (mild/moderate perceived disability). Higher perceived level of function was associated with higher Foot and Ankle Outcome Score values (pain, symptoms, and activities of daily living, p < 0.05). Donor limbs had decreased range of motion and manual muscle testing scores compared with their contralateral limbs (p < 0.05). Lack of ankle support and balance, resulting in limitations and aversions to daily and sporting activities, were the most common themes regarding donor-site challenges. In conclusion, patients who have undergone fibula free flap harvest struggle with ankle support and balance and face functional difficulties that have an impact on their quality of life. Multidisciplinary approaches for targeted rehabilitation after fibula free flap harvest should be explored to determine the impact on patients' quality of life.


Assuntos
Fíbula/transplante , Retalhos de Tecido Biológico/transplante , Procedimentos de Cirurgia Plástica/efeitos adversos , Crânio/cirurgia , Coleta de Tecidos e Órgãos/efeitos adversos , Idoso , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Osteorradionecrose/etiologia , Osteorradionecrose/cirurgia , Medidas de Resultados Relatados pelo Paciente , Projetos Piloto , Qualidade de Vida , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Crânio/patologia , Coleta de Tecidos e Órgãos/métodos , Sítio Doador de Transplante/cirurgia
20.
Plast Reconstr Surg Glob Open ; 9(1): e3374, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33564592

RESUMO

Few studies have evaluated vascularized nerve grafts (VNGs) for facial nerve (CNVII) reconstruction. We sought to evaluate long-term outcomes for CNVII recovery following reconstruction with VNGs. A retrospective review of all patients at a tertiary centre who underwent radical parotidectomy and immediate CNVII reconstruction with VNGs was performed (January 2009-December 2019). Preoperative demographics, perioperative factors (flap type, source of VNGs), and postoperative factors [complications, adjuvant therapy, revisionary procedures, length of follow-up, and CNVII function via the House-Brackmann scale (HB)] were collected. Data were summarized qualitatively. Twelve patients (Mage = 53 ± 18 years) with a mean follow-up of 33 (± 23) months were included. Six patients underwent reconstruction with a radial forearm flap and dorsal sensory branches of the radial nerve. Six patients underwent reconstruction with an anterolateral thigh flap and only deep motor branches of the femoral nerve to the vastus lateralis (n = 4) or combined with the lateral femoral cutaneous nerve (n = 2). Two patients regained nearly normal function (HB = 2). Eight patients regained at least resting symmetry (HB = 3 for n = 7; HB = 4 for n = 1). One patient regained a flicker of movement (HB = 5). One patient did not regain function (HB = 6). Six patients had static revision procedures to improve symmetry. Five patients had disease recurrence; 3 died from their disease. VNGs offer a practical and viable addition to the CNVII reconstruction strategy, and result in good functional recovery with acceptable donor site deficits. The associated adipofascial component of these flaps can also augment the soft tissue defect left after tumor ablation.

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