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1.
Perception ; : 3010066241249451, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38778785

RESUMO

This study aimed to investigate the perception of loudness in response to changes in fundamental frequency (F0) in spoken sounds, as well as the influence of linguistic background on this perceptual process. The results revealed that participants perceived changes in F0 to have accompanying changes in loudness, with a trend of lower F0 sounds being perceived as louder than higher F0 sounds. This finding contrasts with previous studies on pure tones, where increases in frequency typically led to increases in loudness. Furthermore, the study examined differences between two distinct groups of participants: Chinese-speaking and English-speaking individuals. It was observed that English-speaking participants exhibited a greater sensitivity to minor intensity changes compared to Chinese-speaking participants. This discrepancy in sensitivity suggests that linguistic background may play a significant role in shaping the perception of loudness in spoken sound. The study's findings contribute to our understanding of how F0 variations are perceived in terms of loudness, and highlight the potential impact of language experience on this perceptual process.

2.
PLoS Genet ; 17(6): e1009577, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34111113

RESUMO

Frozen shoulder is a painful condition that often requires surgery and affects up to 5% of individuals aged 40-60 years. Little is known about the causes of the condition, but diabetes is a strong risk factor. To begin to understand the biological mechanisms involved, we aimed to identify genetic variants associated with frozen shoulder and to use Mendelian randomization to test the causal role of diabetes. We performed a genome-wide association study (GWAS) of frozen shoulder in the UK Biobank using data from 10,104 cases identified from inpatient, surgical and primary care codes. We used data from FinnGen for replication and meta-analysis. We used one-sample and two-sample Mendelian randomization approaches to test for a causal association of diabetes with frozen shoulder. We identified five genome-wide significant loci. The most significant locus (lead SNP rs28971325; OR = 1.20, [95% CI: 1.16-1.24], p = 5x10-29) contained WNT7B. This variant was also associated with Dupuytren's disease (OR = 2.31 [2.24, 2.39], p<1x10-300) as were a further two of the frozen shoulder associated variants. The Mendelian randomization results provided evidence that type 1 diabetes is a causal risk factor for frozen shoulder (OR = 1.03 [1.02-1.05], p = 3x10-6). There was no evidence that obesity was causally associated with frozen shoulder, suggesting that diabetes influences risk of the condition through glycemic rather than mechanical effects. We have identified genetic loci associated with frozen shoulder. There is a large overlap with Dupuytren's disease associated loci. Diabetes is a likely causal risk factor. Our results provide evidence of biological mechanisms involved in this common painful condition.


Assuntos
Bursite/genética , Diabetes Mellitus/genética , Estudo de Associação Genômica Ampla , Adulto , Bursite/complicações , Complicações do Diabetes/genética , Contratura de Dupuytren/complicações , Humanos , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Fatores de Risco , Reino Unido
3.
Proc Biol Sci ; 290(1999): 20230574, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37221848

RESUMO

Female reproductive fluids (FRFs) serve key reproductive functions in sexually reproducing animals, including modifying the way sperm swim and detect eggs, and influencing sperm lifespan. Despite the central role of FRF during fertilization, we know surprisingly little about sperm-FRF interactions under different environmental conditions. Theory suggests that in external fertilizers FRF may 'rescue' sperm from ageing effects as they search to fertilize eggs. Here, we test the interaction between these two fundamental properties of the fertilization environment, ejaculate age (i.e. time since ejaculation) and FRF, on a range of functional sperm phenotypes in a broadcast spawning mussel, Mytilus galloprovincialis. We found that the effects of ejaculate age on multivariate sperm motility traits and total sperm motility were altered by FRF, and that longer-lived sperm exhibit stronger, likely more advantageous, responses to FRF after periods of ageing. We also detected significant among-male variation in the relationship between sperm motility traits and ejaculate age; notably, these patterns were only revealed when sperm encountered FRF. Collectively these findings underscore the importance of considering female reproductive physiology when interpreting ageing-related declines in sperm motility, as doing so may expose importance sources of variation in sperm phenotypic plasticity among males and environments.


Assuntos
Fertilizantes , Sêmen , Masculino , Feminino , Animais , Motilidade dos Espermatozoides , Envelhecimento , Hormônio Liberador de Gonadotropina , Espermatozoides , Fenótipo
4.
Biol Lett ; 19(11): 20230368, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37991195

RESUMO

Sperm ageing after ejaculation can generate paternal environment effects that impact offspring fitness. In many species, female reproductive fluids (FRFs), i.e. ancillary fluids released by eggs or within the female reproductive tract, may protect sperm from ageing and can additionally interact with sperm to influence offspring viability. This raises the intriguing prospect that FRFs may alleviate paternal effects associated with sperm ageing. Here, we test this novel hypothesis using the broadcast spawning mussel, Mytilus galloprovincialis. We show that incubating sperm in FRF prior to fertilization increases offspring viability, and that these effects occur independently of sperm age. Our results provide novel evidence that FRFs allow females to selectively bias fertilization toward higher quality sperm within an ejaculate, which in turn yields more viable offspring. We consider this FRF-mediated paternal effect in the context of female physiological control over fertilization and the transgenerational effects of female-regulated haploid selection.


Assuntos
Fertilizantes , Herança Paterna , Masculino , Feminino , Humanos , Sêmen , Espermatozoides/fisiologia , Reprodução , Fertilização
5.
Biol Lett ; 18(4): 20220042, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35382588

RESUMO

The continued emissions of anthropogenic carbon dioxide are causing progressive ocean acidification (OA). While deleterious effects of OA on biological systems are well documented in the growth of calcifying organisms, lesser studied impacts of OA include potential effects on gamete interactions that determine fertilization, which are likely to influence the many marine species that spawn gametes externally. Here, we explore the effects of OA on the signalling mechanisms that enable sperm to track egg-derived chemicals (sperm chemotaxis). We focus on the mussel Mytilus galloprovincialis, where sperm chemotaxis enables eggs to bias fertilization in favour of genetically compatible males. Using an experimental design based on the North Carolina II factorial breeding design, we test whether the experimental manipulation of seawater pH (comparing ambient conditions to predicted end-of-century scenarios) alters patterns of differential sperm chemotaxis. While we find no evidence that male-female gametic compatibility is impacted by OA, we do find that individual males exhibit consistent variation in how their sperm perform in lowered pH levels. This finding of individual variability in the capacity of ejaculates to respond to chemoattractants under acidified conditions suggests that climate change will exert considerable pressure on male genotypes that can withstand an increasingly hostile fertilization environment.


Assuntos
Mytilus , Água do Mar , Animais , Feminino , Concentração de Íons de Hidrogênio , Masculino , Mytilus/fisiologia , Água do Mar/química , Interações Espermatozoide-Óvulo , Espermatozoides/fisiologia
6.
Br J Sports Med ; 56(12): 657-666, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35135827

RESUMO

OBJECTIVES: To develop a core outcome set for lateral elbow tendinopathy (COS-LET) and to provide guidance for outcome evaluation in future studies. METHODS: We implemented a multi-stage mixed-methods design combining two systematic reviews, domain mapping of outcome measurement instruments to the core domains of tendinopathy, psychometric analysis of instruments, two patient focus groups and a Delphi study incorporating two surveys and an international consensus meeting. Following the OMERACT guidelines, we used a 70% threshold for consensus. RESULTS: 38 clinicians/researchers and 9 patients participated. 60 instruments were assessed for inclusion. The only instrument that was recommended for the COS-LET was Patient Rated Tennis Elbow Evaluation (PRTEE) for the disability domain. Interim recommendations were made to use: the PRTEE function subscale for the function domain; PRTEE pain subscale items 1, 4 and 5 for the pain over a specified time domain; pain-free grip strength for the physical function capacity domain; a Numerical Rating Scale measuring pain on gripping for the pain on activity/loading domain; and time off work for the participation in life activities domain. No recommendations could be made for the quality-of-life, patient rating of condition and psychological factors domains. CONCLUSIONS: The COS-LET comprises the PRTEE for the disability domain. Interim-use recommendations included PRTEE subscales, time off work, pain-free grip strength and a Numerical Rating Scale measuring pain on gripping. Further work is required to validate these interim measures and develop suitable measures to capture the other domains.


Assuntos
Tendinopatia do Cotovelo , Tendinopatia , Cotovelo de Tenista , Consenso , Tendinopatia do Cotovelo/diagnóstico , Humanos , Avaliação de Resultados em Cuidados de Saúde , Dor , Tendinopatia/diagnóstico , Tendinopatia/psicologia , Cotovelo de Tenista/diagnóstico
7.
Acta Orthop ; 93: 495-502, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35642497

RESUMO

BACKGROUND AND PURPOSE: This study aims to determine, for the first time, generalizable data on the longevity and long-term function of elbow replacements. METHODS: In this systematic review and meta-analysis, we searched MEDLINE and Embase for articles reporting 10-year or greater survival of total elbow replacements (TERs) and distal humeral hemiarthroplasty. Implant survival and patient reported outcome measures (PROMs) data were extracted. National joint replacement registries were also analyzed. We weighted each series and calculated a pooled survival estimate at 10, 15, and 20 years. For PROMs we pooled the standardized mean difference (SMD) at 10 years. FINDINGS: Despite its widespread use, we identified only 9 series reporting all-cause survival of 628 linked TERs and 610 unlinked TERs and no series for distal humeral hemiarthroplasty. The studied population was treated for rheumatoid arthritis in over 90% of cases. The estimated 10-year survival for linked TERs was 92% (95% CI 90-95) and unlinked TERs 84% (CI 81-88). 2 independent registries contributed 32 linked TERs and 530 unlinked TERs. The pooled registry 10-year survival for unlinked TERs was 86% (CI 83-89). Pooled 10-year PROMs from 164 TERs (33 linked and 131 unlinked), revealed a substantial improvement from baseline scores (SMD 2.7 [CI 1.6-3.8]). INTERPRETATION: Over 80% of all elbow replacements and over 90% of linked elbow replacements can last more than 10 years with sustained patient-reported benefits. This information is long overdue and will be particularly useful to patients as well as healthcare providers.


Assuntos
Artroplastia de Substituição , Cotovelo , Seguimentos , Humanos , Sistema de Registros
8.
Biol Lett ; 17(7): 20210213, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34228940

RESUMO

There has been an explosion of recent evidence that environments experienced by fathers or their ejaculates can influence offspring phenotypes (paternal effects). However, little is known about whether such effects are adaptive, which would have far-reaching implications for the many species facing rapidly changing environments. For example, some arguments suggest paternal effects might be a source of cross-generational plasticity, preparing offspring to face similar conditions to their father (anticipatory hypothesis). Alternatively, ejaculate-mediated effects on offspring may be non-adaptive by-products of stress. Here, we conduct an experiment to distinguish between these predictions, exposing ejaculates of the externally fertilizing mussel Mytilus galloprovincialis to ambient (19°C) and high (24°C) temperatures, then rearing offspring groups in temperatures that match and mismatch those of sperm. We find that, overall, high temperature-treated sperm induced higher rates of normal offspring development and higher success in transitioning to second-stage larvae, which may represent adaptive epigenetic changes or selection on sperm haplotypes. However, the progeny of high temperature-treated sperm did not perform better than those of ambient temperature-treated sperm when rearing temperatures were high. Overall, these findings offer little support for the anticipatory hypothesis and suggest instead that beneficial paternal effects may be eroded when offspring develop under stressful conditions.


Assuntos
Mytilus edulis , Herança Paterna , Animais , Fertilização , Masculino , Fenótipo , Espermatozoides
9.
J Shoulder Elbow Surg ; 30(10): 2355-2360, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33675966

RESUMO

AIMS: Shoulder replacement is increasingly performed for end-stage arthritis. Information on the long-term survival and patient outcomes is very limited. This study aimed to quantify the survival and clinical outcome at a minimum of 20-yr follow-up. METHODS: A single-center, single-surgeon, consecutive cohort study was performed. Forty-four shoulder replacements in 40 patients (age at surgery 68.5 years, 82.5% female, preoperative visual analog scale [VAS] pain score 5.1/10, standard deviation [SD] 2.7) implanted between 1996 and 2000 were assessed. All-cause construct survival, radiographic glenoid and humeral stem loosening, radiographic humeral head migration, and patient-reported outcome measures were assessed. RESULTS: Survival with all-cause revision as an endpoint was 84.1% (95% confidence interval [CI] 60.7, 94.1) at 20 years, glenoid loosening was seen in all patients who survived to the 20-year follow-up. Survival of rotator cuff integrity was 16.8% (95% CI 3.5, 38.5) at 20 years. VAS pain scores demonstrated improvement at 10 years (mean change -4/10) but not at 20 years (effect size -0.15, mean change 0.4/10, SD 2.7). At 20 years, 72% of patients had died with the prosthesis in situ. CONCLUSION: Older patients undergoing total shoulder arthroplasty are unlikely to require revision in their lifetime. However, beyond 10 years, a large proportion of implants demonstrate glenoid loosening, humeral head migration, and declining patient outcomes. This information will be of use to patients and clinicians when discussing the potential outcomes of surgery.


Assuntos
Artroplastia do Ombro , Articulação do Ombro , Prótese de Ombro , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Cabeça do Úmero/cirurgia , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/cirurgia , Resultado do Tratamento
10.
J Orthop Traumatol ; 22(1): 47, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34825302

RESUMO

BACKGROUND: Platelet-rich plasma (PRP) is widely used in the management of lateral elbow tendinopathy (LET) despite conflicting evidence on its effectiveness. With high levels of user experience, this study aimed to assess consensus amongst experts on its clinical use. METHODS: A three-round international Delphi study was conducted. Participants were invited through national society mailing lists and contact lists derived from a systematic search of the literature on PRP. In round one, a primary working group developed 40 statements on PRP preparation and clinical application. In rounds two and three, an international group of researchers on PRP and clinical users of the device scored their levels of agreement with the statements on a five-point scale. Consensus was defined as an interquartile range of ≤ 1. RESULTS: Consensus of agreement was only reached for 17/40 (42.5%) statements. For statements on PRP formulation, consensus of agreement was reached in 2/6 statements (33%). Only limited consensus on the contraindications, delivery strategy and delivery technique was achieved. CONCLUSION: Experts reached very limited consensus on the use of PRP in LET. High levels of user experience have not resulted in a convergence of opinion on the technical components of PRP formulation and delivery, substantiating the need for further studies and improved trial reporting.


Assuntos
Tendinopatia do Cotovelo , Doenças Musculoesqueléticas , Plasma Rico em Plaquetas , Tendinopatia , Técnica Delphi , Humanos , Tendinopatia/terapia
11.
Ecol Lett ; 23(3): 447-456, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31840374

RESUMO

Although it is often expected that adverse environmental conditions depress the expression of condition-dependent sexually selected traits, the full consequences of environmental change for the action of sexual selection, in terms of the opportunity for total sexual selection and patterns of phenotypic selection, are unknown. Here we show that dietary stress in guppies, Poecilia reticulata, reduces the expression of several sexually selected traits and increases the opportunity for total sexual selection (standardized variance in reproductive success) in males. Furthermore, our results show that dietary stress modulates the relative importance of precopulatory (mating success) and postcopulatory (relative fertilization success) sexual selection, and that the form of multivariate sexual selection (linear vs. nonlinear) depends on dietary regime. Overall, our results are consistent with a pattern of heightened directional selection on condition-dependent sexually selected traits under environmental stress, and underscore the importance of sexual selection in shaping adaptation in a changing world.


Assuntos
Preferência de Acasalamento Animal , Poecilia , Animais , Dieta , Masculino , Fenótipo , Reprodução , Comportamento Sexual Animal
12.
Lancet ; 393(10172): 647-654, 2019 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-30782340

RESUMO

BACKGROUND: Total hip replacement is a common and highly effective operation. All hip replacements would eventually fail if in situ long enough and it is important that patients understand when this might happen. We aimed to answer the question: how long does a hip replacement last? METHODS: We did a systematic review and meta-analysis with a search of MEDLINE and Embase from the start of records to Sept 12, 2017. We included articles reporting 15-year survival of primary, conventional total hip replacement constructs in patients with osteoarthritis. We extracted survival and implant data and used all-cause construct survival as the primary outcome. We also reviewed reports of national joint replacement registries, and extracted data for a separate analysis. In the meta-analyses, we weighted each series and calculated a pooled survival estimate for each source of data. This study was registered with PROSPERO (CRD42018085642). FINDINGS: We identified 140 eligible articles reporting 150 series, and included 44 of these series (13 212 total hip placements). National joint replacement registries from Australia and Finland provided data for 92 series (215 676 total hip replacements). The 25-year pooled survival of hip replacements from case series was 77·6% (95% CI 76·0-79·2) and from joint replacement registries was 57·9% (95% CI 57·1-58·7). INTERPRETATION: Assuming that estimates from national registries are less likely to be biased, patients and surgeons can expect a hip replacement to last 25 years in around 58% of patients. FUNDING: National Institute for Health Research, National Joint Registry for England, Wales, Northern Ireland and Isle of Man, and The Royal College of Surgeons of England.


Assuntos
Artroplastia de Quadril/efeitos adversos , Falha de Prótese , Sistema de Registros , Reoperação , Seguimentos , Humanos , Osteoartrite do Quadril/cirurgia , Fatores de Tempo
13.
Lancet ; 393(10172): 655-663, 2019 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-30782341

RESUMO

BACKGROUND: Knee replacements are the mainstay of treatment for end-stage osteoarthritis and are effective. Given time, all knee replacements will fail and knowing when this failure might happen is important. We aimed to establish how long a knee replacement lasts. METHODS: In this systematic review and meta-analysis, we searched MEDLINE and Embase for case series and cohort studies published from database inception until July 21, 2018. Articles reporting 15 year or greater survival of primary total knee replacement (TKR), unicondylar knee replacement (UKR), and patellofemoral replacements in patients with osteoarthritis were included. Articles that reviewed specifically complex primary surgeries or revisions were excluded. Survival and implant data were extracted, with all-cause survival of the knee replacement construct being the primary outcome. We also reviewed national joint replacement registry reports and extracted the data to be analysed separately. In the meta-analysis, we weighted each series and calculated a pooled survival estimate for each data source at 15 years, 20 years, and 25 years, using a fixed-effects model. This study is registered with PROSPERO, number CRD42018105188. FINDINGS: From 4363 references found by our initial search, we identified 33 case series in 30 eligible articles, which reported all-cause survival for 6490 TKRs (26 case series) and 742 UKRs (seven case series). No case series reporting on patellofemoral replacements met our inclusion criteria, and no case series reported 25 year survival for TKR. The estimated 25 year survival for UKR (based on one case series) was 72·0% (95% CI 58·0-95·0). Registries contributed 299 291 TKRs (47 series) and 7714 UKRs (five series). The pooled registry 25 year survival of TKRs (14 registries) was 82·3% (95% CI 81·3-83·2) and of UKRs (four registries) was 69·8% (67·6-72·1). INTERPRETATION: Our pooled registry data, which we believe to be more accurate than the case series data, shows that approximately 82% of TKRs last 25 years and 70% of UKRs last 25 years. These findings will be of use to patients and health-care providers; further information is required to predict exactly how long specific knee replacements will last. FUNDING: The National Joint Registry for England, Wales, Northern Ireland, and Isle of Man and the Royal College of Surgeons of England.


Assuntos
Artroplastia do Joelho/efeitos adversos , Falha de Prótese , Sistema de Registros , Reoperação , Seguimentos , Humanos , Osteoartrite do Joelho/cirurgia , Fatores de Tempo
14.
Proc Biol Sci ; 287(1940): 20202538, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33290674

RESUMO

The capacity for parents to influence offspring phenotypes via nongenetic inheritance is currently a major area of focus in evolutionary biology. Intriguing recent evidence suggests that sexual interactions among males and females, both before and during mating, are important mediators of such effects. Sexual interactions typically extend beyond gamete release, involving both sperm and eggs, and their associated fluids. However, the potential for gamete-level interactions to induce nongenetic parental effects remains under-investigated. Here, we test for such effects using an emerging model system for studying gamete interactions, the external fertilizer Mytilus galloprovincialis. We employed a split-ejaculate design to test whether exposing sperm to egg-derived chemicals (ECs) from a female would affect fertilization rate and offspring viability when those sperm were used to fertilize a different female's eggs. We found separate, significant effects of ECs from non-fertilizing females on both fertilization rate and offspring viability. The offspring viability effect indicates that EC-driven interactions can have nongenetic implications for offspring fitness independent of the genotypes inherited by those offspring. These findings provide a rare test of indirect parental effects driven exclusively by gamete-level interactions, and to our knowledge the first evidence that such effects occur via the gametic fluids of females.


Assuntos
Evolução Biológica , Fertilização , Fertilizantes , Placenta/fisiologia , Interações Espermatozoide-Óvulo , Animais , Feminino , Masculino , Modelos Biológicos , Mytilus , Gravidez , Reprodução , Espermatozoides
15.
Proc Biol Sci ; 287(1938): 20202147, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33171088

RESUMO

Sperm cells experience considerable post-ejaculation environmental variation. However, little is known about whether this affects their molecular composition, probably owing to the assumption that sperm are transcriptionally quiescent. Nevertheless, recent evidence shows sperm have distinct RNA profiles that affect fertilization and embryo viability. Moreover, RNAs are expected to be highly sensitive to extracellular changes. One such group of RNAs are heat shock protein (hsp) transcripts, which function in stress responses and are enriched in sperm. Here, we exploit the experimental tractability of the mussel Mytilus galloprovincialis by exposing paired samples of ejaculated sperm to ambient (19°C) and increased (25°C) temperatures, then measure (i) sperm motility phenotypes, and (ii) messenger RNA (mRNA) levels of two target genes (hsp70 and hsp90) and several putative reference genes. We find no phenotypic changes in motility, but reduced mRNA levels for hsp90 and the putative reference gene gapdh at 25°C. This could reflect either decay of specific RNAs, or changes in translation and degradation rates of transcripts to maintain sperm function under stress. These findings represent, to our knowledge, the first evidence for changes in sperm RNA profiles owing to post-ejaculation environments, and suggest that sperm may be more vulnerable to stress from rising temperatures than currently thought.


Assuntos
Ejaculação/fisiologia , Mytilus/fisiologia , RNA , Espermatozoides/fisiologia , Animais , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico/fisiologia , Humanos , Masculino , RNA Mensageiro/metabolismo , Motilidade dos Espermatozoides , Temperatura
16.
Reproduction ; 160(2): R13-R23, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32442963

RESUMO

Environmental pollution is an increasing problem for wildlife globally. Animals are confronted with many different forms of pollution, including chemicals, light, noise, and heat, and these can disrupt critical biological processes such as reproduction. Impacts on reproductive processes can dramatically reduce the number and quality of offspring produced by exposed individuals, and this can have further repercussions on the ecology and evolution of affected populations. Here, we illustrate how environmental pollutants can affect various components of reproduction in wildlife, including direct impacts on reproductive physiology and development, consequences for gamete quality and function, as well as effects on sexual communication, sexual selection, and parental care. We follow with a discussion of the broader ecological and evolutionary consequences of these effects on reproduction and suggest future directions that may enable us to better understand and address the effects of environmental pollution.


Assuntos
Comunicação Animal , Poluentes Ambientais/toxicidade , Preferência de Acasalamento Animal , Reprodução , Animais , Animais Selvagens
17.
J Evol Biol ; 33(6): 797-807, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32125748

RESUMO

Sperm cells exhibit extraordinary phenotypic diversity and rapid rates of evolution, yet the adaptive value of most sperm traits remains equivocal. Recent findings suggest that to understand how selection targets ejaculates, we must recognize that female-imposed physiological conditions often alter sperm phenotypes. These phenotypic changes may influence the relationships among sperm traits and their association with fitness. Here, we show that chemical substances released by eggs (known to modify sperm physiology and behaviour) alter patterns of selection on a suite of sperm traits in the mussel Mytilus galloprovincialis. We use multivariate selection analyses to characterize linear and nonlinear selection acting on sperm traits in (a) seawater alone and (b) seawater containing egg-derived chemicals (egg water). Our analyses revealed that nonlinear selection on canonical axes of multiple traits (notably sperm velocity, sperm linearity and percentage of motile sperm) was the most important form of selection overall, but importantly these patterns were only evident when sperm phenotypes were measured in egg water. These findings reveal the subtle way that females can alter patterns of selection, with the implication that overlooking environmentally moderated changes to sperm, may result in erroneous interpretations of how selection targets phenotypic (co)variation in sperm traits.


Assuntos
Mytilus/genética , Óvulo/fisiologia , Seleção Genética , Espermatozoides , Animais , Feminino , Masculino , Fenótipo
18.
J Evol Biol ; 33(4): 449-459, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31860764

RESUMO

In species with limited opportunities for pre-ejaculatory sexual selection (behavioural components), post-ejaculatory mechanisms may provide opportunities for mate choice after gametes have been released. Recent evidence from a range of taxa has revealed that cryptic female choice (i.e., female-mediated differential fertilization bias), through chemical cues released with or from eggs, can differentially regulate the swimming characteristics of sperm from various males and ultimately determine male fertilization success under sperm competition. We assessed the potential role that such female-modulated chemical cues play in influencing sperm swimming characteristics in beach-spawning capelin (Mallotus villosus), an externally fertilizing fish that mates as couples (one male and one female) or threesomes (two males and one female) with presumably limited opportunities for pre-ejaculatory sexual selection. We assayed sperm swimming characteristics under varying doses and donor origins of egg cues and also examined the possibility of assortative mating based on body size. We found mating groups were not associated by size, larger males did not produce better quality ejaculates, and egg cues (regardless of dosage or donor identity) did not influence sperm swimming characteristics. Our findings suggest that intersexual pre-ejaculatory sexual selection and cryptic female choice mediated by female chemical cues are poorly developed in capelin, possibly due to unique natural selection constraints on reproduction.


Assuntos
Preferência de Acasalamento Animal , Osmeriformes/fisiologia , Animais , Tamanho Corporal , Feminino , Fertilização , Masculino
19.
Biol Lett ; 16(9): 20200411, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32991823

RESUMO

Ejaculate traits vary extensively among individuals and species, but little is known about their variation among populations of the same species. Here, we investigated patterns of intraspecific variation in male reproductive investment in the terrestrial-breeding frog Pseudophryne guentheri. Like most anurans, breeding activity in P. guentheri is cued by precipitation, and therefore the timing and duration of breeding seasons differ among geographically separated populations, potentially leading to differences in the level of sperm competition. We, therefore, anticipated local adaptation in sperm traits that reflect these phenological differences among populations. Our analysis of six natural populations across a rainfall gradient revealed significant divergence in testes and ejaculate traits that correspond with annual rainfall and rainfall seasonality; males from the northern and drier edge of the species range had significantly smaller testes containing fewer, smaller and less motile sperm compared with those from mesic central populations. These findings may reflect spatial variation in the strength of postcopulatory sexual selection, likely driven by local patterns of precipitation.


Assuntos
Anuros , Testículo , Adaptação Fisiológica , Animais , Anuros/genética , Cruzamento , Humanos , Masculino , Espermatozoides
20.
BMC Musculoskelet Disord ; 21(1): 447, 2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32646395

RESUMO

BACKGROUND: The impact of comorbidity on the risk of revision in patients undergoing Total Knee arthroplasty (TKA) and Total Hip Arthroplasty (THA) is not currently well known. The aim of this study was to analyze the impact of comorbidity on the risk of revision in TKA and THA. METHODS: Patients recorded in the Catalan Arthroplasty Register (RACat) between 01/01/2005 and 31/12/2016 undergoing TKA (n = 49,701) and THA (n = 17,923) caused by osteoarthritis were included. As main explanatory factors, comorbidity burden was assessed by the Elixhauser index, categorized, and specific comorbidities from the index were taken into account. Descriptive analyses for comorbidity burden and specific conditions were done. Additionally, incidence at 1 and 5 years' follow-up was calculated, and adjusted Competing Risks models were fitted. RESULTS: A higher incidence of revision was observed when the number of comorbidities was high, both at 1 and 5 years for THA, but only at 1 year for TKA. Of the specific conditions, only obesity was related to the incidence of revision at 1 year in both joints, and at 5 years in TKA. The risk of revision was related to deficiency anemia and liver diseases in TKA, while in THA, it was related to peripheral vascular disorders, metastatic cancer and psychoses. CONCLUSIONS: Different conditions, depending on the joint, might be related to higher revision rates. This information could be relevant for clinical decision-making, patient-specific information and improving the results of both TKA and THA.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Comorbidade , Humanos , Obesidade , Reoperação , Estudos Retrospectivos
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