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1.
Harm Reduct J ; 21(1): 26, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38287409

RESUMEN

BACKGROUND: Adulterants, such as fentanyl and xylazine, among others, are present in a high percentage of the illicit drug supply, increasing the risk for overdose and other adverse health events among people who use drugs (PWUD). Point-of-care drug checking identifies components of a drug sample and delivers results consumers. To successfully meet the diverse needs of PWUD, more information is needed about the utility of drug checking, motivations for using services contextualized in broader comments on the drug supply, hypothesized actions to be taken after receiving drug checking results, and the ideal structure of a program. METHODS: In December 2021, semi-structured interviews were conducted with 40 PWUD who were accessing harm reduction services in Philadelphia, PA. Participants were asked about opinions and preferences for a future drug checking program. Interviews were audio recorded, transcribed and coded using content analysis to identify themes. RESULTS: Participants were primarily White (52.5%) and male (60%). Heroin/fentanyl was the most frequently reported drug used (72.5%, n = 29), followed by crack cocaine (60.0%, n = 24) and powder cocaine (47.5%, n = 19). Emerging themes from potential drug checking consumers included universal interest in using a drug checking program, intentions to change drug use actions based on drug checking results, deep concern about the unpredictability of the drug supply, engaging in multiple harm reduction practices, and concerns about privacy while accessing a service. CONCLUSIONS: We offer recommendations for sites considering point-of-care drug checking regarding staffing, safety, logistics, and cultural competency. Programs should leverage pre-existing relationships with organizations serving PWUD and hire people with lived experiences of drug use. They should work with local or state government to issue protections to people accessing drug checking programs and ensure the service is anonymous and that data collection is minimized to keep the program low-threshold. Programs will ideally operate in multiple locations and span "atmosphere" (e.g., from clinical to a drop-in culture), offer in-depth education to participants about results, engage with a community advisory board, and not partner with law enforcement.


Asunto(s)
Sobredosis de Droga , Drogas Ilícitas , Trastornos Relacionados con Sustancias , Humanos , Masculino , Philadelphia , Sistemas de Atención de Punto , Sobredosis de Droga/prevención & control , Fentanilo/análisis , Drogas Ilícitas/análisis , Reducción del Daño , Analgésicos Opioides/análisis
2.
J Exp Biol ; 226(14)2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37350275

RESUMEN

Eastern oysters, Crassostrea virginica, are facing rapid environmental changes in the northern Gulf of Mexico and can respond to these changes via plasticity or evolution. Plastic responses can immediately buffer against environmental changes, although this buffering may impact the organism's ability to evolve in subsequent generations. While plasticity and evolution are not mutually exclusive, the relative contribution and interaction between them remains unclear. In this study, we investigated the roles of plastic and evolved responses of C. virginica acclimated to low salinity using a common garden experiment with four populations exposed to two salinities. We used three transcriptomic analyses (edgeR, PERMANOVA and WGCNA) combined with physiology data to identify the effect of genotype (population), environment (salinity) and the genotype-environment interaction on both whole-organism and molecular phenotypes. We demonstrate that variation in gene expression is mainly driven by population, with relatively small changes in response to salinity. In contrast, the morphology and physiology data reveal that salinity has a larger influence on oyster performance than the population of origin. All analyses lacked signatures of the genotype×environment interaction and, in contrast to previous studies, we found no evidence for population-specific responses to low salinity. However, individuals from the highest salinity estuary displayed highly divergent gene expression from that of other populations, which could potentially drive population-specific responses to other stressors. Our findings suggest that C. virginica largely rely on plasticity in physiology to buffer the effects of low salinity, but that these changes in physiology do not rely on large persistent changes in gene expression.


Asunto(s)
Crassostrea , Animales , Crassostrea/fisiología , Salinidad , Golfo de México , Perfilación de la Expresión Génica , Aclimatación
3.
Mol Biol Evol ; 38(4): 1306-1316, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33306808

RESUMEN

As species struggle to keep pace with the rapidly warming climate, adaptive introgression of beneficial alleles from closely related species or populations provides a possible avenue for rapid adaptation. We investigate the potential for adaptive introgression in the copepod, Tigriopus californicus, by hybridizing two populations with divergent heat tolerance limits. We subjected hybrids to strong heat selection for 15 generations followed by whole-genome resequencing. Utilizing a hybridize evolve and resequence (HER) technique, we can identify loci responding to heat selection via a change in allele frequency. We successfully increased the heat tolerance (measured as LT50) in selected lines, which was coupled with higher frequencies of alleles from the southern (heat tolerant) population. These repeatable changes in allele frequencies occurred on all 12 chromosomes across all independent selected lines, providing evidence that heat tolerance is polygenic. These loci contained genes with lower protein-coding sequence divergence than the genome-wide average, indicating that these loci are highly conserved between the two populations. In addition, these loci were enriched in genes that changed expression patterns between selected and control lines in response to a nonlethal heat shock. Therefore, we hypothesize that the mechanism of heat tolerance divergence is explained by differential gene expression of highly conserved genes. The HER approach offers a unique solution to identifying genetic variants contributing to polygenic traits, especially variants that might be missed through other population genomic approaches.


Asunto(s)
Adaptación Biológica/genética , Copépodos/genética , Introgresión Genética , Selección Genética , Termotolerancia/genética , Animales , Femenino , Frecuencia de los Genes , Masculino , Secuenciación Completa del Genoma
4.
Mol Ecol ; 31(10): 3002-3017, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35303383

RESUMEN

Bioeroding sponges interact and compete with corals on tropical reefs. Experimental studies have shown global change alters this biotic interaction, often in favour of the sponge. Ocean acidification in particular increases sponge bioerosion and reduces coral calcification, yet little is known about the molecular basis of these changes. We used RNA-Seq data to understand how acidification impacts the interaction between the bioeroding sponge, Cliona varians, and the coral, Porites furcata, at the transcriptomic level. Replicate sponge and coral genets were exposed to ambient (8.1 pH) and acidified (7.6 pH) conditions in isolation and in treatments where they were joined for 48 h. The coral had a small gene expression response (tens of transcripts) to the sponge, suggesting it does little at the transcriptomic level to deter sponge overgrowth. By contrast, the sponge differentially expressed 7320 transcripts in response to the coral under ambient conditions and 3707 transcripts in response to acidification. Overlap in the responses to acidification and the coral, 2500 transcripts expressed under both treatments, suggests a similar physiological response to both cues. The sponge expressed 50× fewer transcripts in response to the coral under acidification, suggesting energetic costs of bioerosion, and other cellular processes, are lower for sponges under acidification. Our results suggest how acidification drives ecosystem-level changes in the accretion/bioerosion balance on coral reefs. This shift is not only the result of changes to the thermodynamic balance of these chemical reactions but also the result of active physiological responses of organisms to each other and their abiotic environment.


Asunto(s)
Antozoos , Poríferos , Animales , Antozoos/genética , Arrecifes de Coral , Ecosistema , Concentración de Iones de Hidrógeno , Océanos y Mares , Poríferos/genética , Agua de Mar/química , Transcriptoma/genética
5.
J Anim Ecol ; 91(6): 1135-1147, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34882793

RESUMEN

It has been hypothesized that environmentally induced changes to gene body methylation could facilitate adaptive transgenerational responses to changing environments. We compared patterns of global gene expression (Tag-seq) and gene body methylation (reduced representation bisulfite sequencing) in 80 eastern oysters Crassostrea virginica from six full-sib families, common gardened for 14 months at two sites in the northern Gulf of Mexico that differed in mean salinity. At the time of sampling, oysters from the two sites differed in mass by 60% and in parasite loads by nearly two orders of magnitude. They also differentially expressed 35% of measured transcripts. However, we observed differential methylation at only 1.4% of potentially methylated loci in comparisons between individuals from these different environments, and little correspondence between differential methylation and differential gene expression. Instead, methylation patterns were largely driven by genetic differences among families, with a PERMANOVA analysis indicating nearly a two orders of magnitude greater number of genes differentially methylated between families than between environments. An analysis of CpG observed/expected values (CpG O/E) across the C. virginica genome showed a distinct bimodal distribution, with genes from the first cluster showing the lower CpG O/E values, greater methylation and higher and more stable gene expression, while genes from the second cluster showed lower methylation, and lower and more variable gene expression. Taken together, the differential methylation results suggest that only a small portion of the C. virginica genome is affected by environmentally induced changes in methylation. At this point, there is little evidence to suggest that environmentally induced methylation states would play a leading role in regulating gene expression responses to new environments.


Asunto(s)
Crassostrea , Animales , Crassostrea/genética , Metilación de ADN , Expresión Génica , Salinidad , Análisis de Secuencia de ADN
6.
Proc Biol Sci ; 288(1951): 20203118, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-34004136

RESUMEN

Salinity conditions in oyster breeding grounds in the Gulf of Mexico are expected to drastically change due to increased precipitation from climate change and anthropogenic changes to local hydrology. We determined the capacity of the eastern oyster, Crassostrea virginica, to adapt via standing genetic variation or acclimate through transgenerational plasticity (TGP). We outplanted oysters to either a low- or medium-salinity site in Louisiana for 2 years. We then crossed adult parents using a North Carolina II breeding design, and measured body size and survival of larvae 5 dpf raised under low or ambient salinity. We found that TGP is unlikely to significantly contribute to low-salinity tolerance since we did not observe increased growth or survival in offspring reared in low salinity when their parents were also acclimated at a low-salinity site. However, we detected genetic variation for body size, with an estimated heritability of 0.68 ± 0.25 (95% CI). This suggests there is ample genetic variation for this trait to evolve, and that evolutionary adaptation is a possible mechanism through which oysters will persist with future declines in salinity. The results of this experiment provide valuable insights into successfully breeding low-salinity tolerance in this commercially important species.


Asunto(s)
Crassostrea , Animales , Crassostrea/genética , Golfo de México , Louisiana , North Carolina , Salinidad
7.
Proc Biol Sci ; 288(1958): 20210765, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34493077

RESUMEN

Many species face extinction risks owing to climate change, and there is an urgent need to identify which species' populations will be most vulnerable. Plasticity in heat tolerance, which includes acclimation or hardening, occurs when prior exposure to a warmer temperature changes an organism's upper thermal limit. The capacity for thermal acclimation could provide protection against warming, but prior work has found few generalizable patterns to explain variation in this trait. Here, we report the results of, to our knowledge, the first meta-analysis to examine within-species variation in thermal plasticity, using results from 20 studies (19 species) that quantified thermal acclimation capacities across 78 populations. We used meta-regression to evaluate two leading hypotheses. The climate variability hypothesis predicts that populations from more thermally variable habitats will have greater plasticity, while the trade-off hypothesis predicts that populations with the lowest heat tolerance will have the greatest plasticity. Our analysis indicates strong support for the trade-off hypothesis because populations with greater thermal tolerance had reduced plasticity. These results advance our understanding of variation in populations' susceptibility to climate change and imply that populations with the highest thermal tolerance may have limited phenotypic plasticity to adjust to ongoing climate warming.


Asunto(s)
Aclimatación , Termotolerancia , Adaptación Fisiológica , Cambio Climático , Ecosistema , Temperatura
8.
Mol Ecol ; 30(22): 5721-5734, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34462983

RESUMEN

Eastern oysters in the northern Gulf of Mexico are facing rapid environmental changes and can respond to this change via plasticity or evolution. Plasticity can act as an immediate buffer against environmental change, but this buffering could impact the organism's ability to evolve in subsequent generations. While plasticity and evolution are not mutually exclusive, the relative contribution and interaction between them remains unclear. In this study, we investigate the roles of plastic and evolved responses to environmental variation and Perkinsus marinus infection in Crassostrea virginica by using a common garden experiment with 80 oysters from six families outplanted at two field sites naturally differing in salinity. We use growth data, P. marinus infection intensities, 3' RNA sequencing (TagSeq) and low-coverage whole-genome sequencing to identify the effect of genotype, environment and genotype-by-environment interaction on the oyster's response to site. As one of first studies to characterize the joint effects of genotype and environment on transcriptomic and morphological profiles in a natural setting, we demonstrate that C. virginica has a highly plastic response to environment and that this response is parallel among genotypes. We also find that genes responding to genotype have distinct and opposing profiles compared to genes responding to environment with regard to expression levels, Ka/Ks ratios and nucleotide diversity. Our findings suggest that C. virginica may be able to buffer the immediate impacts of future environmental changes by altering gene expression and physiology, but the lack of genetic variation in plasticity suggests limited capacity for evolved responses.


Asunto(s)
Crassostrea , Animales , Crassostrea/genética , Interacción Gen-Ambiente , Genotipo , Humanos , Salinidad , Transcriptoma
9.
J Evol Biol ; 34(8): 1212-1224, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33837581

RESUMEN

The large geographic distribution of the eastern oyster, Crassostrea virginica, makes it an ideal species to test how populations have adapted to latitudinal gradients in temperature. Despite inhabiting distinct thermal regimes, populations of C. virginica near the species' southern and northern geographic range show no population differences in their physiological response to temperature. In this study, we used comparative transcriptomics to understand how oysters from either end of the species' range maintain enantiostasis across three acclimation temperatures (10, 20, and 30°C). With this approach, we identified genes that were differentially expressed in response to temperature between individuals of C. virginica collected from New Brunswick, Canada and Louisiana, USA. We observed a core set of genes whose expression responded to temperature in both populations, but also an even larger set of genes with expression patterns that were unique to each population. Intriguingly, the genes with population-specific responses to temperature had elevated FST and Ka/Ks ratios compared to the genome-wide average. In contrast, genes showing only a response to temperature were found to only have elevated FST values suggesting that divergent FST may be due to selection on linked regulatory regions rather than positive selection on protein coding regions. Taken together, our results suggest that, despite coarse-scale physiological similarities, natural selection has shaped divergent gene expression responses to temperature in geographically separated populations of this broadly eurythermal marine invertebrate.


Asunto(s)
Crassostrea , Aclimatación , Adaptación Fisiológica/genética , Animales , Crassostrea/genética , Humanos , Temperatura , Transcriptoma
10.
J Therm Biol ; 100: 103072, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34503809

RESUMEN

The eastern oyster, Crassostrea virginica, provides critical ecosystem services and supports valuable fishery and aquaculture industries in northern Gulf of Mexico (nGoM) subtropical estuaries where it is grown subtidally. Its upper critical thermal limit is not well defined, especially when combined with extreme salinities. The cumulative mortalities of the progenies of wild C. virginica from four nGoM estuaries differing in mean annual salinity, acclimated to low (4.0), moderate (20.0), and high (36.0) salinities at 28.9 °C (84 °F) and exposed to increasing target temperatures of 33.3 °C (92 °F), 35.6 °C (96 °F) or 37.8 °C (100 °F), were measured over a three-week period. Oysters of all stocks were the most sensitive to increasing temperatures at low salinity, dying quicker (i.e., lower median lethal time, LT50) than at the moderate and high salinities and resulting in high cumulative mortalities at all target temperatures. Oysters of all stocks at moderate salinity died the slowest with high cumulative mortalities only at the two highest temperatures. The F1 oysters from the more southern and hypersaline Upper Laguna Madre estuary were generally more tolerant to prolonged higher temperatures (higher LT50) than stocks originating from lower salinity estuaries, most notably at the highest salinity. Using the measured temperatures oysters were exposed to, 3-day median lethal Celsius degrees (LD50) were estimated for each stock at each salinity. The lowest 3-day LD50 (35.1-36.0 °C) for all stocks was calculated at a salinity of 4.0, while the highest 3-day LD50 (40.1-44.0 °C) was calculated at a salinity of 20.0.


Asunto(s)
Crassostrea/fisiología , Calentamiento Global , Tolerancia a la Sal , Animales , Biomasa , Crassostrea/crecimiento & desarrollo , Golfo de México , Termotolerancia
12.
Mol Ecol ; 28(11): 2715-2730, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30770604

RESUMEN

Ocean acidification (OA), the global decrease in surface water pH from absorption of anthropogenic CO2 , may put many marine taxa at risk. However, populations that experience extreme localized conditions, and are adapted to these conditions predicted in the global ocean in 2,100, may be more tolerant to future OA. By identifying locally adapted populations, researchers can examine the mechanisms used to cope with decreasing pH. One oceanographic process that influences pH is wind-driven upwelling. Here we compare two Californian populations of the coral Balanophyllia elegans from distinct upwelling regimes, and test their physiological and transcriptomic responses to experimental seawater acidification. We measured respiration rates, protein and lipid content, and gene expression in corals from both populations exposed to pH levels of 7.8 and 7.4 for 29 days. Corals from the population that experiences lower pH due to high upwelling maintained the same respiration rate throughout the exposure. In contrast, corals from the low upwelling site had reduced respiration rates, protein content and lipid-class content at low pH exposure, suggesting they have depleted their energy reserves. Using RNA-Seq, we found that corals from the high upwelling site upregulated genes involved in calcium ion binding and ion transport, most likely related to pH homeostasis and calcification. In contrast, corals from the low upwelling site downregulated stress response genes at low pH exposure. Divergent population responses to low pH observed in B. elegans highlight the importance of multi-population studies for predicting a species' response to future OA.


Asunto(s)
Ácidos/metabolismo , Antozoos/fisiología , Ambiente , Océanos y Mares , Aerobiosis , Animales , Antozoos/genética , Análisis Discriminante , Regulación de la Expresión Génica , Ontología de Genes , Redes Reguladoras de Genes , Concentración de Iones de Hidrógeno , Lípidos/análisis , Análisis de Componente Principal , Proteínas/análisis
13.
Mol Ecol ; 27(7): 1621-1632, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29509986

RESUMEN

Species inhabiting the North American west coast intertidal must tolerate an extremely variable environment, with large fluctuations in both temperature and salinity. Uncovering the mechanisms for this tolerance is key to understanding species' persistence. We tested for differences in salinity tolerance between populations of Tigriopus californicus copepods from locations in northern (Bodega Reserve) and southern (San Diego) California known to differ in temperature, precipitation and humidity. We also tested for differences between populations in their transcriptomic responses to salinity. Although these two populations have ~20% mtDNA sequence divergence and differ strongly in other phenotypic traits, we observed similarities in their phenotypic and transcriptomic responses to low and high salinity stress. Salinity significantly affected respiration rate (increased under low salinity and reduced under high salinity), but we found no significant effect of population on respiration or a population by salinity interaction. Under high salinity, there was no population difference in knock-down response, but northern copepods had a smaller knock-down under low salinity stress, corroborating previous results for T. californicus. Northern and southern populations had a similar transcriptomic response to salinity based on a principle components analysis, although differential gene expression under high salinity stress was three times lower in the northern population compared to the southern population. Transcripts differentially regulated under salinity stress were enriched for "amino acid transport" and "ion transport" annotation categories, supporting previous work demonstrating that the accumulation of free amino acids is important for osmotic regulation in T. californicus.


Asunto(s)
Copépodos/genética , Geografía , Estrés Salino/genética , Transcriptoma/genética , Aerobiosis , Animales , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Sitios Genéticos , Modelos Logísticos , Masculino , Fenotipo , Análisis de Componente Principal , ARN Mensajero/genética , ARN Mensajero/metabolismo , Salinidad
14.
Mol Ecol ; 27(5): 1120-1137, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29411447

RESUMEN

Understanding the mechanisms with which organisms can respond to a rapidly changing ocean is an important research priority in marine sciences, especially in the light of recent predictions regarding the pace of ocean change in the coming decades. Transgenerational effects, in which the experience of the parental generation can shape the phenotype of their offspring, may serve as such a mechanism. In this study, adult purple sea urchins, Strongylocentrotus purpuratus, were conditioned to regionally and ecologically relevant pCO2 levels and temperatures representative of upwelling (colder temperature and high pCO2 ) and nonupwelling (average temperature and low pCO2 ) conditions typical of coastal upwelling regions in the California Current System. Following 4.5 months of conditioning, adults were spawned and offspring were raised under either high or low pCO2 levels, to examine the role of maternal effects. Using RNA-seq and comparative transcriptomics, our results indicate that differential conditioning of the adults had an effect on the gene expression patterns of the progeny during the gastrula stage of early development. For example, maternal conditioning under upwelling conditions intensified the transcriptomic response of the progeny when they were raised under high versus low pCO2 conditions. Additionally, mothers that experienced upwelling conditions produced larger progeny. The overall findings of this study are complex, but do suggest that transgenerational plasticity in situ could act as an important mechanism by which populations might keep pace with rapid environmental change.


Asunto(s)
Dióxido de Carbono/farmacología , Strongylocentrotus purpuratus/genética , Aclimatación , Animales , Cambio Climático , Frío , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/genética , Exposición Materna , Strongylocentrotus purpuratus/crecimiento & desarrollo , Strongylocentrotus purpuratus/fisiología
15.
Subst Use Misuse ; 53(5): 837-843, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29172867

RESUMEN

BACKGROUND: Research indicates healthcare workers' personal substance use may affect quality of care. Investigating factors that correlate with coping through substance use may provide insight into improving quality care. OBJECTIVES: This study aims to examine potential correlates of coping through substance use among healthcare workers, with a particular focus on humor, social support, stress perception, and smoking temptation. METHOD: Participants, recruited from healthcare facilities, anonymously completed a 30-minute questionnaire of psychometrically valid measurements. RESULTS: In a sample of primarily female (75.7%), age 20-39 (74.8%), floor staff (i.e., doctors, nurses, technicians/assistants; 61.2%), perceived stress [ß = .036, t(98) = 2.55, p = .012], smoking temptation [ß = .036, t(98) = 2.21, p = .030], and coping through humor [ß = .163, t(98) = 2.033, p = .045] were significant correlates of the coping through substance use, with all relationships positively co-varying. Social support at work did not predict coping through substance use [ß = -.032, t(98) = -.814, p > .05]. Furthermore, negative affect/situation smoking temptation was associated with increased coping through substance use [ß = .246, t(99) = 2.859, p = .005] and habit/craving temptation was associated with decreased coping through substance use [ß = -.260, t(99) = -2.201, p = .030; however, positive affect/social temptation was not [ß = .054, t(99) = -.553, p > .05]. Conclusions/Importance: These findings suggest that coping with humor may relate to coping through substance use, while social support at work is either unrelated to coping through substance use in this sample or may not be adequately assessed with the measure used. Consistent with the literature, negative affect/situation was associated with increased coping through substance use. However, habit/craving was negatively predictive. Further research should explore the variables related to coping through substance use among healthcare workers.


Asunto(s)
Adaptación Psicológica/fisiología , Consumidores de Drogas/psicología , Personal de Salud , Fumar/psicología , Estrés Psicológico/psicología , Trastornos Relacionados con Sustancias/psicología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Apoyo Social , Ingenio y Humor como Asunto
16.
J Hered ; 107(1): 71-81, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26519514

RESUMEN

Physiological plasticity and adaptive evolution may facilitate persistence in a changing environment. As a result, there is an interest in understanding species' capacities for plastic and evolved responses, and the mechanisms by which these responses occur. Transcriptome sequencing has become a powerful tool for addressing these questions, providing insight into otherwise unobserved effects of changing conditions on organismal physiology and variation in these effects among individuals and populations. Here, we review recent studies using comparative transcriptomics to understand plastic and evolutionary responses to changing environments. We focus on 2 areas where transcriptomics has played an important role: first, in understanding the genetic basis for local adaptation to current gradients as a proxy for future adaptation, and second, in understanding organismal responses to multiple stressors. We find most studies examining multiple stressors have tested the effects of each stressor individually; the few studies testing multiple stressors simultaneously have found synergistic effects on gene expression that would not have been predicted from single stressor studies. We discuss the importance of robust experimental design to allow for a more sophisticated characterization of transcriptomic responses and conclude by offering recommendations for future research, including integrating genomics with transcriptomics, testing gene regulatory networks, and comparing the equivalence of transcription to translation and the effects of environmental stress on the proteome.


Asunto(s)
Adaptación Biológica/genética , Evolución Biológica , Cambio Climático , Perfilación de la Expresión Génica , Ambiente , Genómica , Fenotipo , Proyectos de Investigación , Estrés Fisiológico , Temperatura , Transcriptoma
17.
Artículo en Inglés | MEDLINE | ID: mdl-25773301

RESUMEN

Advances in nucleic acid sequencing technology are removing obstacles that historically prevented use of genomics within ocean change biology. As one of the first marine calcifiers to have its genome sequenced, purple sea urchins (Strongylocentrotus purpuratus) have been the subject of early research exploring genomic responses to ocean acidification, work that points to future experiments and illustrates the value of expanding genomic resources to other marine organisms in this new 'post-genomic' era. This review presents case studies of S. purpuratus demonstrating the ability of genomic experiments to address major knowledge gaps within ocean acidification. Ocean acidification research has focused largely on species vulnerability, and studies exploring mechanistic bases of tolerance toward low pH seawater are comparatively few. Transcriptomic responses to high pCO2 seawater in a population of urchins already encountering low pH conditions have cast light on traits required for success in future oceans. Secondly, there is relatively little information on whether marine organisms possess the capacity to adapt to oceans progressively decreasing in pH. Genomics offers powerful methods to investigate evolutionary responses to ocean acidification and recent work in S. purpuratus has identified genes under selection in acidified seawater. Finally, relatively few ocean acidification experiments investigate how shifts in seawater pH combine with other environmental factors to influence organism performance. In S. purpuratus, transcriptomics has provided insight into physiological responses of urchins exposed simultaneously to warmer and more acidic seawater. Collectively, these data support that similar breakthroughs will occur as genomic resources are developed for other marine species.


Asunto(s)
Cambio Climático , Strongylocentrotus purpuratus/genética , Adaptación Psicológica , Animales , Dióxido de Carbono/química , Genómica , Humanos , Concentración de Iones de Hidrógeno , Agua de Mar/química , Strongylocentrotus purpuratus/fisiología
18.
Am Nat ; 181(6): 846-54, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23669546

RESUMEN

Antagonistic correlations among traits may slow the rate of adaptation to a changing environment. The tide pool copepod Tigriopus californicus is locally adapted to temperature, but within populations, the response to selection for increased heat tolerance plateaus rapidly, suggesting either limited variation within populations or costs of increased tolerance. To measure possible costs of thermal tolerance, we selected for increased upper lethal limits for 10 generations in 22 lines of T. californicus from six populations. Then, for each line, we measured six fitness-related traits. Selected lines showed an overall increase in male and female body sizes, fecundity, and starvation resistance, suggesting a small benefit from (rather than costs of) increased tolerance. The effect of selection on correlated traits also varied significantly by population for five traits, indicating that the genetic basis for the selection response differed among populations. Our results suggest that adaptation was limited by the presence of variation within isolated populations rather than by costs of increased tolerance.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Copépodos/genética , Aptitud Genética , Calor , Selección Genética , Análisis de Varianza , Animales , California , Cambio Climático , Copépodos/fisiología , Femenino , Variación Genética , Geografía , Masculino , Oregon
19.
Proc Biol Sci ; 280(1759): 20130155, 2013 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-23536595

RESUMEN

Ocean warming and ocean acidification, both consequences of anthropogenic production of CO2, will combine to influence the physiological performance of many species in the marine environment. In this study, we used an integrative approach to forecast the impact of future ocean conditions on larval purple sea urchins (Strongylocentrotus purpuratus) from the northeast Pacific Ocean. In laboratory experiments that simulated ocean warming and ocean acidification, we examined larval development, skeletal growth, metabolism and patterns of gene expression using an orthogonal comparison of two temperature (13°C and 18°C) and pCO2 (400 and 1100 µatm) conditions. Simultaneous exposure to increased temperature and pCO2 significantly reduced larval metabolism and triggered a widespread downregulation of histone encoding genes. pCO2 but not temperature impaired skeletal growth and reduced the expression of a major spicule matrix protein, suggesting that skeletal growth will not be further inhibited by ocean warming. Importantly, shifts in skeletal growth were not associated with developmental delay. Collectively, our results indicate that global change variables will have additive effects that exceed thresholds for optimized physiological performance in this keystone marine species.


Asunto(s)
Dióxido de Carbono/metabolismo , Agua de Mar/química , Strongylocentrotus purpuratus/fisiología , Animales , California , Perfilación de la Expresión Génica , Calentamiento Global , Calor , Larva/anatomía & histología , Larva/genética , Larva/crecimiento & desarrollo , Larva/fisiología , Modelos Logísticos , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Filogenia , Análisis de Secuencia de ADN , Strongylocentrotus purpuratus/anatomía & histología , Strongylocentrotus purpuratus/genética , Strongylocentrotus purpuratus/crecimiento & desarrollo
20.
Respir Med ; 218: 107397, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37640274

RESUMEN

RATIONALE: Alternatives to center-based pulmonary rehabilitation are needed to improve patient access to this important therapy. A critical challenge to overcome is how to maximize safety of unsupervised exercise for at-risk patients. We investigated if a novel remote monitoring-enabled mobile health (mHealth) program is safe, feasible, and effective for patients who experience exercise-induced hemoglobin desaturation. METHODS: An interstitial lung disease (ILD) commonly associated with pronounced exercise desaturation was investigated - the rare, female-predominant ILD lymphangioleiomyomatosis (LAM). Over a 12-week program, hemoglobin saturation (SpO2) was continuously recorded during all home exercise sessions. Intervention effects were assessed with 6-min walk test (6MWT), maximal cardiopulmonary exercise test (CPET), lower extremity computerized dynamometry, pulmonary function tests, and health-related quality of life (QoL) surveys. Safety was assessed by blood biomarkers of systemic inflammation and cardiac wall stress, and incidence of adverse events. RESULTS: Fifteen LAM patients enrolled and 14 completed the intervention, with high adherence to aerobic (87 ± 15%) and strength (87 ± 12%) training components. An innovative characterization of exercise training SpO2 revealed that while mild-to-moderate desaturation was common during home workouts, participants were able to self-adjust exercise intensity and supplemental oxygen levels to maintain recommended exercise parameters. Significant improvements included 6MWT distance (+36 ± 34 m, p = 0.003), CPET time (p = 0.04), muscular endurance (p = 0.008), QoL (p = 0.009 to 0.03), and fatigue (p = 0.001 to 0.03). Patient acceptability and satisfaction indicators were high, blood biomarkers remained stable (p > 0.05), and no study-related adverse events occurred. CONCLUSION: A remote monitoring-enabled home exercise program is a safe, feasible, and effective approach even for patients who experience exercise desaturation.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Calidad de Vida , Humanos , Femenino , Prueba de Esfuerzo , Terapia por Ejercicio/efectos adversos , Tolerancia al Ejercicio , Biomarcadores , Hemoglobinas , Prescripciones
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