RESUMO
The US opioid crisis came in three waves - prescription opioids, heroin, and illicitly manufactured fentanyls - Centers for Disease Control and Prevention Centers for Disease Control and Prevention resulting in the deaths of nearly 500,000 people from 1996 to 2019. In 2009, drug overdose deaths exceeded those involving automobiles. Opioid overdose deaths contributed to the decrease in life expectancy for Americans from 78.8 to 78.5 during 2014 to 2017. The overprescribing of a schedule II prescription opioid was escalated by pharmaceutical companies promoting a growing belief that pain was an undertreated condition. In 2012, the number of opioid prescriptions peaked at 255 million and deaths exceeded 11,000 per year. The typical prescription opioid abuser was white, male, and 45-55 years of age. The hardest-hit states were in Appalachia and the Northeast. When an abuse-resistant formulation was introduced for OxyContin, the most prevalent prescription opioid, users turned to heroin. From the early 1980s, a new pizza delivery style of Mexican trafficking in black tar heroin infiltrated many of the same states hit hardest by prescription opioids. Heroin overdose deaths reached 14,495 in 2017. As heroin abuse increased in states supplied with black tar heroin, fentanyl-contaminated white powder heroin began to appear in the Northeast. Fentanyl was quickly followed by fentanyl analogs. While heroin deaths continued to escalate through 2017, they were soon overshadowed by fentanyl overdose deaths. Finally, prescription opioid and heroin overdose deaths started to decline in 2017, though fentanyl deaths continued to increase. In late 2019, it appeared that restrictions on transportation and travel due to the COVID-19 pandemic had resulted in decreased availability of illicit drugs, but by 2020 drug abuse had escalated in many countries. Globally, heroin was the primary opioid of abuse and only a few countries - including Canada, Germany, Austria, and Belgium - have experienced a significant increase in prescription opioids. However, illicitly manufactured fentanyls are a growing problem in North America, Europe, Australia, and Asia.
Assuntos
Analgésicos Opioides , COVID-19 , Analgésicos Opioides/efeitos adversos , Humanos , Masculino , Epidemia de Opioides , Pandemias , Prevalência , SARS-CoV-2 , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Life-history theory predicts a trade-off between investment into immune defence and other fitness-related traits. Accordingly, individuals are expected to upregulate their immune response when subjected to immune challenge. However, this is predicted to come at the expense of investment into a range of other traits that are costly to maintain, such as growth, reproduction and survival. Currently, it remains unclear whether the magnitude of such costs, and trade-offs involving immune investment and other traits, manifests consistently across species and sexes. To address this, we conducted a meta-analysis to investigate how changes in sex, ontogenetic stage and environmental factors shape phenotypic trait expression following an immune challenge. RESULTS: We explored the effects of immune challenge on three types of traits across sexually reproducing metazoans: life-history, morphological and proximate immune traits (235 effect sizes, 53 studies, 37 species [21 invertebrates vs. 16 vertebrates]). We report a general negative effect of immune challenge on survival and reproduction, a positive effect on immune trait expression, but no effect on morphology or development time. The negative effects of immune challenge on reproductive traits and survival were larger in females than males. We also report a pronounced effect of the immune treatment agent used (e.g. whether the treatment involved a live pathogen or not) on the host response to immune challenge, and find an effect of mating status on the host response in invertebrates. CONCLUSION: These results suggest that costs associated with immune deployment following an immune challenge are context-dependent and differ consistently in their magnitude across the sexes of diverse taxonomic lineages. We synthesise and discuss the outcomes in the context of evolutionary theory on sex differences in life-history and highlight the need for future studies to carefully consider the design of experiments aimed at disentangling the costs of immune deployment.
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Sistema Imunitário/fisiologia , Invertebrados/imunologia , Características de História de Vida , Vertebrados/imunologia , Animais , Evolução Biológica , Meio Ambiente , Feminino , Crescimento , Invertebrados/crescimento & desenvolvimento , Masculino , Caracteres Sexuais , Fatores Sexuais , Vertebrados/crescimento & desenvolvimentoRESUMO
STUDY QUESTION: Does an informed group of citizens endorse the clinical use of mitochondrial donation in a country where this is not currently permitted? SUMMARY ANSWER: After hearing balanced expert evidence and having opportunity for deliberation, a majority (11/14) of participants in a citizens' jury believed that children should be able to be born using mitochondrial donation. WHAT IS KNOWN ALREADY: Research suggests that patients, oocyte donors and health professionals support mitochondrial donation to prevent transmission of mitochondrial disease. Less is known about public acceptability of this novel reproductive technology, especially from evidence using deliberative methods. STUDY DESIGN, SIZE, DURATION: This study comprised a citizens' jury, an established method for determining the views of a well-informed group of community members. The jury had 14 participants, and ran over one and a half days in 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Jurors were members of the public with no experience of mitochondrial disease. They heard and engaged with relevant evidence and were asked to answer the question: 'Should Australia allow children to be born following mitochondrial donation?' MAIN RESULTS AND THE ROLE OF CHANCE: Eleven jurors decided that Australia should allow children to be born following mitochondrial donation; 7 of whom added conditions such as the need to limit who can access the intervention. Three jurors decided that children should not (or not yet) be born using this intervention. All jurors were particularly interested in the reliability of evidence, licensing/regulatory mechanisms and the rights of children to access information about their oocyte donors. LIMITATIONS, REASONS FOR CAUTION: Jurors' views were well informed and reflected critical deliberation and discussion, but are not intended to be representative of the whole population. WIDER IMPLICATIONS OF THE FINDINGS: When presented with high quality evidence, combined with opportunities to undertake structured deliberation of novel reproductive technologies, members of the public are able to engage in detailed discussions. This is the first study to use an established deliberative method to gauge public views towards mitochondrial donation. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by a University of Sydney Industry and Community Collaboration Seed Award (2017), which was awarded contingent on additional funding from the Mito Foundation. Additional funding was provided by the Mito Foundation. The Foundation was not involved in jury facilitation or deliberation, nor analysis of research data. TRIAL REGISTRATION NUMBER: Not applicable.
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Atitude , Doenças Mitocondriais/prevenção & controle , Terapia de Substituição Mitocondrial/legislação & jurisprudência , Terapia de Substituição Mitocondrial/métodos , Doação de Oócitos/legislação & jurisprudência , Doação de Oócitos/métodos , Opinião Pública , Adolescente , Adulto , Idoso , Austrália , Tomada de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Formulação de Políticas , Adulto JovemRESUMO
The static water contact angle (CA) quantifies the degree of wetting that occurs when a surface encounters a liquid, e.g. water. This property is a result of factors such as surface chemistry and local roughness and is an important analytical parameter linked to the suitability of a surface for a given bioanalytical process. Monitoring the spatial variation in wettability over surfaces is increasingly critical to analysts and manufacturers for improved quality control. However, CA acquisition is often time-consuming because it involves measurements over multiple spatial locations, independent sampling and the need for a single instrument operator. Furthermore, surfaces exposed to local environments specific to an intended application may affect the surface chemistry thereby modifying the surface properties. In this study, Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) chemical imaging data acquired from wet and dry polymer surfaces were used to develop multivariate predictive models for CA prediction. Partial Least Squares Regression (PLSR) models were built using IR spectra from surfaces presenting differences in the experimentally measured CA in the range 16°-141°. The best performing PLSR models were locally developed and combined to make a global model utilising wet IR spectra which performed well (R2p = 0.98, RMSECV â¼ 5°) when tested on an independent experimental set. This model was subsequently applied to IR spectra acquired from a surface exhibiting spatial differences in surface chemistry and the CA with a reasonable confidence and precision (prediction error within 10°), demonstrating the potential of this method for prediction of the spatially varying CA as a non-destructive in-line process monitoring technique.
RESUMO
Evolutionary theory predicts maternal inheritance of the mitochondria will lead to the accumulation of mutations in the mitochondrial DNA (mtDNA) that impair male fertility, but leave females unaffected. The hypothesis has been referred to as 'Mother's Curse'. There are many examples of mtDNA mutations or haplotypes, in humans and other metazoans, associated with decreases in sperm performance, but seemingly few reports of associations involving female reproductive traits; an observation that has been used to support the Mother's Curse hypothesis. However, it is unclear whether apparent signatures of male bias in mitochondrial genetic effects on fertility reflect an underlying biological bias or a technical bias resulting from a lack of studies to have screened for female effects. Here, we conduct a systematic literature search of studies reporting mitochondrial genetic effects on fertility-related traits in gonochoristic metazoans (animals with two distinct sexes). Studies of female reproductive outcomes were sparse, reflecting a large technical sex bias across the literature. We were only able to make a valid assessment of sex specificity of mitochondrial genetic effects in 30% of cases. However, in most of these cases, the effects were male biased, including examples of male bias associated with mtDNA mutations in humans. These results are therefore consistent with the hypothesis that maternal inheritance has enriched mtDNA sequences with mutations that specifically impair male fertility. However, future research that redresses the technical imbalance in studies conducted per sex will be key to enabling researchers to fully assess the wider implications of the Mother's Curse hypothesis to male reproductive biology.
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Infertilidade Masculina/etiologia , Herança Materna , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Mutação , Reprodução , Animais , Feminino , Humanos , Infertilidade Masculina/patologia , MasculinoRESUMO
Mitochondrial genetic variation shapes the expression of life-history traits associated with reproduction, development and survival, and has also been associated with the prevalence and progression of infectious bacteria and viruses in humans. The breadth of these effects on multifaceted components of health, and their link to disease susceptibility, led us to test whether variation across mitochondrial haplotypes affected reproductive success following an immune challenge in the form of a non-infectious pathogen. We test this, by challenging male and female fruit flies (Drosophila melanogaster), harbouring each of three distinct mitochondrial haplotypes in an otherwise standardized genetic background, to either a mix of heat-killed bacteria, or a procedural control, prior to measuring their subsequent reproductive performance. The effect of the pathogen challenge on reproductive success did not differ across mitochondrial haplotypes; thus there was no evidence that patterns of reproductive plasticity were modified by the mitochondrial genotype following a non-infectious pathogen exposure. We discuss the implications of our data, and suggest future research avenues based on these results.
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Drosophila/genética , Genoma Mitocondrial , Genótipo , Reprodução , Animais , Bactérias/patogenicidade , Drosophila/microbiologia , Drosophila/fisiologia , Feminino , Haplótipos , Características de História de Vida , Masculino , Polimorfismo GenéticoRESUMO
Reproduction and aging evolved to be intimately associated. Experimental selection for early-life reproduction drives the evolution of decreased longevity in Drosophila whereas experimental selection for increased longevity leads to changes in reproduction. Although life history theory offers hypotheses to explain these relationships, the genetic architecture and molecular mechanisms underlying reproduction-longevity associations remain a matter of debate. Here we show that mating triggers accelerated mortality in males and identify hundreds of genes that are modulated upon mating in the fruit fly Drosophila melanogaster. Interrogation of genome-wide gene expression in virgin and recently mated males revealed coherent responses, with biological processes that are upregulated (testis-specific gene expression) or downregulated (metabolism and mitochondria-related functions) upon mating. Furthermore, using a panel of genotypes from the Drosophila Synthetic Population Resource (DSPR) as a source of naturally occurring genetic perturbation, we uncover abundant variation in longevity and reproduction-induced mortality among genotypes. Genotypes displayed more than fourfold variation in longevity and reproduction-induced mortality that can be traced to variation in specific segments of the genome. The data reveal individual variation in sensitivity to reproduction and physiological processes that are enhanced and suppressed upon mating. These results raise the prospect that variation in longevity and age-related traits could be traced to processes that coordinate germline and somatic function.
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Drosophila melanogaster/genética , Expressão Gênica , Longevidade/genética , Animais , Regulação para Baixo , Genótipo , Masculino , Reprodução/genética , Comportamento Sexual Animal , Testículo/fisiologia , Regulação para CimaRESUMO
BACKGROUND: Phenotypic plasticity operates across generations, when the parental environment affects phenotypic expression in the offspring. Recent studies in invertebrates have reported transgenerational plasticity in phenotypic responses of offspring when the mothers had been previously exposed to either live or heat-killed pathogens. Understanding whether this plasticity is adaptive requires a factorial design in which both mothers and their offspring are subjected to either the pathogen challenge or a control, in experimentally matched and mismatched combinations. Most prior studies exploring the capacity for pathogen-mediated transgenerational plasticity have, however, failed to adopt such a design. Furthermore, it is currently poorly understood whether the magnitude or direction of pathogen-mediated transgenerational responses will be sensitive to environmental heterogeneity. Here, we explored the transgenerational consequences of a dual pathogen and stress challenge administered in the maternal generation in the fruit fly, Drosophila melanogaster. Prospective mothers were assigned to a non-infectious pathogen treatment consisting of an injection with heat-killed bacteria or a procedural control, and a stress treatment consisting of sleep deprivation or control. Their daughters and sons were similarly assigned to the same pathogen treatment, prior to measurement of their reproductive success. RESULTS: We observed transgenerational interactions involving pathogen treatments of mothers and their offspring, on the reproductive success of daughters but not sons. These interactions were unaffected by sleep deprivation. CONCLUSIONS: The direction of the transgenerational effects was not consistent with that predicted under a scenario of adaptive transgenerational plasticity. Instead, they were indicative of expectations based on terminal investment.
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Drosophila melanogaster/fisiologia , Adaptação Fisiológica , Animais , Drosophila melanogaster/microbiologia , Meio Ambiente , Feminino , Masculino , Reprodução , Estresse FisiológicoAssuntos
Colite Colagenosa , Metotrexato , Administração Oral , Colágeno , Humanos , ImunossupressoresRESUMO
BACKGROUND: The Barwon area in Australia has one of the highest incidence rates of inflammatory bowel disease (IBD) and therefore is an ideal location to study the impact of environmental exposures on the disease's development. AIM: To study these exposures prior to the development of IBD in a population-based cohort. METHOD: One hundred and thirty-two incident cases (81 Crohn disease (CD) and 51 ulcerative colitis (UC)) from an IBD registry and 104 controls replied to the International Organization of Inflammatory Bowel Diseases environmental questionnaire. This included 87 questions about pre-illness exposures that included childhood illnesses, vaccinations, breastfeeding, house amenities, pets and swimming, diet and smoking. RESULTS: The factors associated with CD included smoking (odds ratio (OR): 1.42, confidence interval (CI): 1-2.02, P = 0.029); childhood events, including tonsillectomy (OR: 1.74, CI: 1.15-2.6, P = 0.003) and chicken pox infection (OR: 3.89, CI: 1.61-9.4, P = 0.005) and pre-diagnosis intake of frequent fast food (OR: 2.26, CI: 1.76-4.33, P = 0.003). In UC, the risk factors included smoking (OR: 1.39, CI: 1.1-1.92, P = 0.026) and pre-diagnosis intake of frequent fast food (OR: 2.91, CI: 1.54-5.58, P < 0.001), and high caffeine intake was protective (OR: 0.51, 95% CI: 0.3-0.87, P = 0.002). Other protective exposures for UC included high fruit intake (OR: 0.59, CI: 0.4-0.88, P = 0.003) and having pets as a child (OR: 0.36, CI: 0.2-0.79, P = 0.001). CONCLUSION: This first Australian population-based study of environmental risk factors confirms that smoking, childhood immunological events and dietary factors play a role in IBD development; while high caffeine intake and pet ownership offer a protective effect.
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Dieta , Doenças Inflamatórias Intestinais/epidemiologia , Estilo de Vida , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Estudos de Casos e Controles , Varicela/epidemiologia , Criança , Fast Foods/efeitos adversos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Sistema de Registros , Fatores de Risco , Fumar/epidemiologia , Inquéritos e Questionários , Tonsilectomia/estatística & dados numéricos , Adulto JovemRESUMO
The ancient acquisition of the mitochondrion into the ancestor of modern-day eukaryotes is thought to have been pivotal in facilitating the evolution of complex life. Mitochondria retain their own diminutive genome, with mitochondrial genes encoding core subunits involved in oxidative phosphorylation. Traditionally, it was assumed that there was little scope for genetic variation to accumulate and be maintained within the mitochondrial genome. However, in the past decade, mitochondrial genetic variation has been routinely tied to the expression of life-history traits such as fertility, development and longevity. To examine whether these broad-scale effects on life-history trait expression might ultimately find their root in mitochondrially mediated effects on core bioenergetic function, we measured the effects of genetic variation across twelve different mitochondrial haplotypes on respiratory capacity and mitochondrial quantity in the fruit fly, Drosophila melanogaster. We used strains of flies that differed only in their mitochondrial haplotype, and tested each sex separately at two different adult ages. Mitochondrial haplotypes affected both respiratory capacity and mitochondrial quantity. However, these effects were highly context-dependent, with the genetic effects contingent on both the sex and the age of the flies. These sex- and age-specific genetic effects are likely to resonate across the entire organismal life-history, providing insights into how mitochondrial genetic variation may contribute to sex-specific trajectories of life-history evolution.
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Envelhecimento/genética , Evolução Biológica , Drosophila/genética , Genes Mitocondriais/genética , Variação Genética , Fosforilação Oxidativa , Animais , Feminino , Masculino , Mitocôndrias/genética , Fatores SexuaisAssuntos
Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Preparações de Plantas/efeitos adversos , Prednisolona/uso terapêutico , Valeriana , Humanos , Masculino , Pessoa de Meia-Idade , Esteroides/uso terapêutico , Resultado do TratamentoRESUMO
BACKGROUND: The thiopurine drugs, 6-mercaptopurine and azathioprine, remain the mainstay of immunomodulator therapy for inflammatory bowel disease (IBD). Optimal management depends on achieving therapeutic levels of 6-thioguanine (6-TGN), but measuring thiopurine metabolites is associated with significant cost. Thiopurines cause lymphopenia and an increase in mean corpuscular volume (MCV). It is unclear whether any clinically useful correlation exists between 6-TGN levels and lymphocyte count or MCV. AIMS: The aim of this study is to investigate the correlation between 6-TGN levels and lymphocyte count and MCV in thiopurine-treated patients with IBD. METHODS: We analysed a prospectively acquired database of 67 patients with IBD treated with thiopurine therapy. The data were analysed looking at the relationship between 6-TGN levels and both lymphocyte count and MCV by using the Spearman's rank correlation coefficient. RESULTS: Twenty-seven (40%) patients had therapeutic 6-TGN levels. Thirty-three (49%) patients had sub-therapeutic 6-TGN levels. A weak positive correlation between 6-TGN levels and lymphocyte count was demonstrated, but this was not statistically significant (Spearman's R = 0.14, P = 0.23). Spearman's rank correlation coefficient between 6-TGN levels and MCV was statistically significant (R = 0.42, P = 0.0005). MCV >101 fL excluded a subtherapeutic 6-TGN level with positive predictive value of 92%. CONCLUSIONS: There is no specific lymphopenia that can be assumed to indicate a therapeutic 6-TGN level. The relationship between 6-TGN levels and MCV is likely to be clinically relevant. If MCV is elevated, 6-TGN is unlikely to be sub-therapeutic. MCV is a potential surrogate marker which can rule out sub-therapeutic thiopurine metabolites in patients with IBD treated with azathioprine or 6-mercaptopurine.
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Azatioprina/uso terapêutico , Índices de Eritrócitos/fisiologia , Doenças Inflamatórias Intestinais/sangue , Linfopenia/sangue , Mercaptopurina/uso terapêutico , Tioguanina/sangue , Adulto , Azatioprina/farmacologia , Biomarcadores/sangue , Índices de Eritrócitos/efeitos dos fármacos , Feminino , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Linfopenia/diagnóstico , Masculino , Mercaptopurina/farmacologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Some regions of the genome exhibit sexual asymmetries in inheritance and are thus subjected to sex-biased evolutionary forces. Maternal inheritance of mitochondrial DNA (mtDNA) enables mtDNA mutations harmful to males, but not females, to accumulate. In the face of male-harmful mtDNA mutation accumulation, selection will favour the evolution of compensatory modifiers in the nuclear genome that offset fitness losses to males. The Y chromosome is a candidate to host these modifiers, because it is paternally inherited, known to harbour an abundance of genetic variation for male fertility, and therefore likely to be under strong selection to uphold male viability. Here, we test for intergenomic interactions involving mtDNA and Y chromosomes in male Drosophila melanogaster. Specifically, we examine effects of each of these genomic regions, and their interaction, on locomotive activity, across different environmental contexts--both dietary and social. We found that both the mtDNA haplotype and Y chromosome haplotype affected activity in males assayed in an environment perceived as social. These effects, however, were not evident in males assayed in perceived solitary environments, and neither social nor solitary treatments revealed evidence for intergenomic interactions. Finally, the magnitude and direction of these genetic effects was further contingent on the diet treatment of the males. Thus, genes within the mtDNA and Y chromosome are involved in genotype-by-environment interactions. These interactions might contribute to the maintenance of genetic variation within these asymmetrically inherited gene regions and complicate the dynamics of genetic interactions between the mtDNA and the Y chromosome.
Assuntos
DNA Mitocondrial/genética , Drosophila melanogaster/genética , Haplótipos , Locomoção , Cromossomo Y , Animais , MasculinoAssuntos
Colonoscopia/economia , Neoplasias Colorretais/economia , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/economia , Programas de Rastreamento/economia , Sangue Oculto , Atitude do Pessoal de Saúde , Neoplasias Colorretais/diagnóstico , Análise Custo-Benefício , Árvores de Decisões , Humanos , Programas de Rastreamento/métodos , Valor Preditivo dos Testes , Inquéritos e QuestionáriosRESUMO
It is well established that the parental phenotype can influence offspring phenotypic expression, independent of the effects of the offspring's own genotype. Nonetheless, the evolutionary implications of such parental effects remain unclear, partly because previous studies have generally overlooked the potential for interactions between parental sources of non-genetic variance to influence patterns of offspring phenotypic expression. We tested for such interactions, subjecting male and female Drosophila melanogaster of two different age classes to an immune activation challenge or a control treatment. Flies were then crossed in all age and immune status combinations, and the reproductive success of their immune- and control-treated daughters measured. We found that daughters produced by two younger parents exhibited reduced reproductive success relative to those of other parental age combinations. Furthermore, immune-challenged daughters exhibited higher reproductive success when produced by immune-challenged relative to control-treated mothers, a pattern consistent with transgenerational immune priming. Finally, a complex interplay between paternal age and parental immune statuses influenced daughter's reproductive success. These findings demonstrate the dynamic nature of age- and immune-mediated parental effects, traceable to both parents, and regulated by interactions between parents and between parents and offspring.
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Drosophila melanogaster/fisiologia , Fertilidade/fisiologia , Pais , Animais , Drosophila melanogaster/imunologia , Feminino , Fertilidade/imunologia , Masculino , Micrococcus luteusRESUMO
Genetic variation in cytoplasmic genomes (i.e. the mitochondrial genome in animals, and the combined mitochondrial and chloroplast genomes in plants) was traditionally assumed to accumulate under a neutral equilibrium model. This view has, however, come under increasing challenge from studies that have experimentally linked cytoplasmic genetic effects to the expression of life history phenotypes. Such results suggest that genetic variance located within the cytoplasm might be of evolutionary importance and potentially involved in shaping population evolutionary trajectories. As a step towards assessing this assertion, here we conduct a formal meta-analytic review to quantitatively assess the extent to which cytoplasmic genetic effects contribute to phenotypic expression across animal and plant kingdoms. We report that cytoplasmic effect sizes are generally moderate in size and associated with variation across a range of factors. Specifically, cytoplasmic effects on morphological traits are generally larger than those on life history or metabolic traits. Cytoplasmic effect sizes estimated at the between-species scale (via interspecies mix-and-matching of cytoplasmic and nuclear genomes) are larger than those at the within-species scale. Furthermore, cytoplasmic effects tied to epistatic interactions with the nuclear genome tend to be stronger than additive cytoplasmic effects, at least when restricting the data set to gonochorous animal species. Our results thus confirm that cytoplasmic genetic variation is commonly tied to phenotypic expression across plants and animals, implicate the cytoplasmic-nuclear interaction as a key unit on which natural selection acts and generally suggest that the genetic variation that lies within the cytoplasm is likely to be entwined in adaptive evolutionary processes.
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Evolução Biológica , Citoplasma/genética , Genoma de Cloroplastos , Genoma Mitocondrial , Fenótipo , Animais , Núcleo Celular/genética , Feminino , Variação Genética , Modelos Lineares , Masculino , Modelos Genéticos , Plantas/genéticaRESUMO
We describe a case of congenital cataracts in a newborn whose mother received total parenteral nutrition (TPN) throughout her pregnancy. We discuss the potential mechanisms by which TPN may have been causally linked to cataract formation.
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Catarata/etiologia , Fenômenos Fisiológicos da Nutrição Materna , Nutrição Parenteral Total/efeitos adversos , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Adulto JovemRESUMO
Immune responses are highly dynamic. The magnitude and efficiency of an immune response to a pathogen can change markedly across individuals, and such changes may be influenced by variance in a range of intrinsic (e.g. age, genotype, sex) and external (e.g. abiotic stress, pathogen identity, strain) factors. Life history theory predicts that up-regulation of the immune system will come at a physiological cost, and studies have confirmed that increased investment in immunity can reduce reproductive output and survival. Furthermore, males and females often have divergent reproductive strategies, and this might drive the evolution of sex-specific life history trade-offs involving immunity, and sexual dimorphism in immune responses per se. Here, we employ an experiment design to elucidate dose-dependent and sex-specific responses to exposure to a nonpathogenic immune elicitor at two scales--the 'ultimate' life history and the underlying 'proximate' immune level in Drosophila melanogaster. We found dose-dependent effects of immune challenges on both male and female components of reproductive success, but not on survival, as well as a response in antimicrobial activity. These results indicate that even in the absence of the direct pathogenic effects that are associated with actual disease, individual life histories respond to a perceived immune challenge--but with the magnitude of this response being contingent on the initial dose of exposure. Furthermore, the results indicate that immune responses at the ultimate life history level may indeed reflect underlying processes that occur at the proximate level.