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1.
J Hum Evol ; 181: 103395, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37320961

RESUMEN

The morphological adaptations of euprimates have been linked to their origin and early evolution in an arboreal environment. However, the ancestral and early locomotor repertoire of this group remains contentious. Although some tarsal bones like the astragalus and the calcaneus have been thoroughly studied, the navicular remains poorly studied despite its potential implications for foot mobility. Here, we evaluate early euprimate locomotion by assessing the shape of the navicular-an important component of the midtarsal region of the foot-using three-dimensional geometric morphometrics in relation to quantified locomotor repertoire in a wide data set of extant primates. We also reconstruct the locomotor repertoire of representatives of the major early primate lineages with a novel phylogenetically informed discriminant analysis and characterize the changes that occurred in the navicular during the archaic primate-euprimate transition. To do so, we included in our study an extensive sample of naviculars (36 specimens) belonging to different species of adapiforms, omomyiforms, and plesiadapiforms. Our results indicate that navicular shape embeds a strong functional signal, allowing us to infer the type of locomotion of extinct primates. We demonstrate that early euprimates displayed a diverse locomotor behavior, although they did not reach the level of specialization of some living forms. Finally, we show that the navicular bone experienced substantial reorganization throughout the archaic primate-euprimate transition, supporting the major functional role of the tarsus during early primate evolution. This study demonstrates that navicular shape can be used as a reliable proxy for primate locomotor behavior. In addition, it sheds light on the diverse locomotor behavior of early primates as well as on the archaic primate-euprimate transition, which involved profound morphological changes within the tarsus, including the navicular bone.


Asunto(s)
Evolución Biológica , Astrágalo , Animales , Fósiles , Astrágalo/anatomía & histología , Primates/anatomía & histología , Pie/anatomía & histología , Locomoción
2.
Philos Trans R Soc Lond B Biol Sci ; 378(1880): 20220083, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37183904

RESUMEN

The placental skull has evolved into myriad forms, from longirostrine whales to globular primates, and with a diverse array of appendages from antlers to tusks. This disparity has recently been studied from the perspective of the whole skull, but the skull is composed of numerous elements that have distinct developmental origins and varied functions. Here, we assess the evolution of the skull's major skeletal elements, decomposed into 17 individual regions. Using a high-dimensional morphometric approach for a dataset of 322 living and extinct eutherians (placental mammals and their stem relatives), we quantify patterns of variation and estimate phylogenetic, allometric and ecological signal across the skull. We further compare rates of evolution across ecological categories and ordinal-level clades and reconstruct rates of evolution along lineages and through time to assess whether developmental origin or function discriminate the evolutionary trajectories of individual cranial elements. Our results demonstrate distinct macroevolutionary patterns across cranial elements that reflect the ecological adaptations of major clades. Elements derived from neural crest show the fastest rates of evolution, but ecological signal is equally pronounced in bones derived from neural crest and paraxial mesoderm, suggesting that developmental origin may influence evolutionary tempo, but not capacity for specialisation. This article is part of the theme issue 'The mammalian skull: development, structure and function'.


Asunto(s)
Evolución Biológica , Placenta , Embarazo , Animales , Femenino , Filogenia , Cráneo , Cabeza , Mamíferos/genética , Primates , Cetáceos
3.
Bioessays ; 45(7): e2200243, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37075758

RESUMEN

Lactase persistence/persistent (LP), the ability to express the lactase enzyme in adults, is one of the most strongly selected phenotypes in humans. It is encoded by at least five genetic variants that have rapidly become widespread in various human populations. The underlying selective mechanism is not clear however, because dairy products in general are well tolerated in adults, even by lactase non-persistence/persistent (LNP) individuals. Cultural adaptations to milk consumption, notably fermentation and transformation, which can provide most of the energy (protein, fat) to both LP and LNP individuals without any associated cost seem to have been common in ancient societies. Here, we propose that selection for LP occurred through increased glucose/galactose (energy) from fresh milk intake in early childhood, a crucial period for growth. At the age of weaning indeed, lactase activity has already begun to decline in LNP individuals so the gain in energy from fresh milk by LP children represents a major fitness increase.


Asunto(s)
Intolerancia a la Lactosa , Adulto , Niño , Preescolar , Humanos , Lactasa/genética , Intolerancia a la Lactosa/genética , Leche
4.
Elife ; 122023 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-36700542

RESUMEN

Vertebrate limb morphology often reflects the environment due to variation in locomotor requirements. However, proximal and distal limb segments may evolve differently from one another, reflecting an anatomical gradient of functional specialization that has been suggested to be impacted by the timing of development. Here, we explore whether the temporal sequence of bone condensation predicts variation in the capacity of evolution to generate morphological diversity in proximal and distal forelimb segments across more than 600 species of mammals. Distal elements not only exhibit greater shape diversity, but also show stronger within-element integration and, on average, faster evolutionary responses than intermediate and upper limb segments. Results are consistent with the hypothesis that late developing distal bones display greater morphological variation than more proximal limb elements. However, the higher integration observed within the autopod deviates from such developmental predictions, suggesting that functional specialization plays an important role in driving within-element covariation. Proximal and distal limb segments also show different macroevolutionary patterns, albeit not showing a perfect proximo-distal gradient. The high disparity of the mammalian autopod, reported here, is consistent with the higher potential of development to generate variation in more distal limb structures, as well as functional specialization of the distal elements.


Asunto(s)
Evolución Biológica , Mamíferos , Animales , Mamíferos/fisiología , Extremidad Superior , Miembro Anterior/fisiología , Huesos
5.
Science ; 378(6618): 377-383, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36302012

RESUMEN

The Cenozoic diversification of placental mammals is the archetypal adaptive radiation. Yet, discrepancies between molecular divergence estimates and the fossil record fuel ongoing debate around the timing, tempo, and drivers of this radiation. Analysis of a three-dimensional skull dataset for living and extinct placental mammals demonstrates that evolutionary rates peak early and attenuate quickly. This long-term decline in tempo is punctuated by bursts of innovation that decreased in amplitude over the past 66 million years. Social, precocial, aquatic, and herbivorous species evolve fastest, especially whales, elephants, sirenians, and extinct ungulates. Slow rates in rodents and bats indicate dissociation of taxonomic and morphological diversification. Frustratingly, highly similar ancestral shape estimates for placental mammal superorders suggest that their earliest representatives may continue to elude unequivocal identification.


Asunto(s)
Evolución Biológica , Euterios , Cráneo , Animales , Femenino , Euterios/anatomía & histología , Fósiles , Filogenia , Roedores , Cráneo/anatomía & histología
6.
Forensic Sci Int ; 330: 111133, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34891082

RESUMEN

Few countries systematically record and publish detailed information on the types, caliber, and makes of ammunition recovered by law enforcement. This results in a lack of knowledge of the ammunition used in crime, including in the European context. This pilot study examines the utility of ballistic datasets for monitoring illicit ammunition. The ballistic laboratories of four European countries-Denmark, Germany, Sweden, and Switzerland-provided access to non-confidential subsets of their national databases, including the caliber of recovered cartridge cases as well as the year and type of incident in which they were used. The laboratories also shared images of the ammunition headstamp markings, which helped determine each cartridge case's manufacturer and-when known-year of production. The resulting dataset covers 3130 cartridge cases documented by the participating laboratories between 2015 and the first quarter of 2020. Although limited in scope-the research team did not have access to geocoded data so spatial comparisons were limited to the country level-the dataset helps generate a baseline of the main varieties of ammunition used in crime, by country and crime category, and over time. Most of the ammunition (61 per cent) was recovered in the context of violent types of crime-homicides and assaults-for which pistol ammunition calibers were the most prominent. 610 unique headstamps were recorded, but only a small proportion of these varieties of ammunition accounted for most of the cases. All four country datasets included both foreign-made ammunition as well as cartridges produced domestically. The year of manufacture could be identified for 28 per cent of the cartridges, and at least 27 pieces of ammunition were produced in the same year that the criminal incident took place, which suggests recent diversion from licit holdings. The dataset revealed additional trends such as the criminal use of blank ammunition in all four case studies, as well as the relatively new prevalence of the 7,62 × 39 caliber-which is typically used with AK-pattern rifles-in one country. In addition to shedding new light on the types of ammunition used in crime in the European context, monitoring illicit ammunition across space and over time has the potential to support police investigations with intelligence on criminals' sources of supply.

7.
Evolution ; 75(11): 2685-2707, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34382693

RESUMEN

Phenotypictraits have been shown to evolve in response to variation in the environment. However, the evolutionary processes underlying the emergence of phenotypic diversity can typically only be understood at the population level. Consequently, how subtle phenotypic differences at the intraspecific level can give rise to larger-scale changes in performance and ecology remains poorly understood. We here tested for the covariation between ecology, bite force, jaw muscle architecture, and the three-dimensional shape of the cranium and mandible in 16 insular populations of the lizards Podarcis melisellensis and P. sicula. We then compared the patterns observed at the among-population level with those observed at the interspecific level. We found that three-dimensional head shape as well as jaw musculature evolve similarly under similar ecological circumstances. Depending on the type of food consumed or on the level of sexual competition, different muscle groups were more developed and appeared to underlie changes in cranium and mandible shape. Our findings show that the local selective regimes are primary drivers of phenotypic variation resulting in predictable patterns of form and function. Moreover, intraspecific patterns of variation were generally consistent with those at the interspecific level, suggesting that microevolutionary variation may translate into macroevolutionary patterns of ecomorphological diversity.


Asunto(s)
Lagartos , Animales , Lagartos/genética
8.
Nat Commun ; 12(1): 2503, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33947859

RESUMEN

Habitat is one of the most important factors shaping organismal morphology, but it may vary across life history stages. Ontogenetic shifts in ecology may introduce antagonistic selection that constrains adult phenotype, particularly with ecologically distinct developmental phases such as the free-living, feeding larval stage of many frogs (Lissamphibia: Anura). We test the relative influences of developmental and ecological factors on the diversification of adult skull morphology with a detailed analysis of 15 individual cranial regions across 173 anuran species, representing every extant family. Skull size, adult microhabitat, larval feeding, and ossification timing are all significant factors shaping aspects of cranial evolution in frogs, with late-ossifying elements showing the greatest disparity and fastest evolutionary rates. Size and microhabitat show the strongest effects on cranial shape, and we identify a "large size-wide skull" pattern of anuran, and possibly amphibian, evolutionary allometry. Fossorial and aquatic microhabitats occupy distinct regions of morphospace and display fast evolution and high disparity. Taxa with and without feeding larvae do not notably differ in cranial morphology. However, loss of an actively feeding larval stage is associated with higher evolutionary rates and disparity, suggesting that functional pressures experienced earlier in ontogeny significantly impact adult morphological evolution.


Asunto(s)
Ecosistema , Conducta Alimentaria , Larva/crecimiento & desarrollo , Cráneo/anatomía & histología , Animales , Anuros , Evolución Biológica , Larva/anatomía & histología , Larva/metabolismo , Osteogénesis/fisiología , Filogenia , Análisis de Componente Principal , Cráneo/crecimiento & desarrollo
9.
Proc Biol Sci ; 288(1949): 20210319, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33906406

RESUMEN

Differences in jaw function experienced through ontogeny can have striking consequences for evolutionary outcomes, as has been suggested for the major clades of mammals. By contrast to placentals, marsupial newborns have an accelerated development of the head and forelimbs, allowing them to crawl to the mother's teats to suckle within just a few weeks of conception. The different functional requirements that marsupial newborns experience in early postnatal development have been hypothesized to have constrained their morphological diversification relative to placentals. Here, we test whether marsupials have a lower ecomorphological diversity and rate of evolution in comparison with placentals, focusing specifically on their jaws. To do so, a geometric morphometric approach was used to characterize jaw shape for 151 living and extinct species of mammals spanning a wide phylogenetic, developmental and functional diversity. Our results demonstrate that jaw shape is significantly influenced by both reproductive mode and diet, with substantial ecomorphological convergence between metatherians and eutherians. However, metatherians have markedly lower disparity and rate of mandible shape evolution than observed for eutherians. Thus, despite their ecomorphological diversity and numerous convergences with eutherians, the evolution of the jaw in metatherians appears to be strongly constrained by their specialized reproductive biology.


Asunto(s)
Marsupiales , Animales , Evolución Biológica , Euterios , Maxilares , Filogenia
10.
Front Med (Lausanne) ; 8: 637987, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33681264

RESUMEN

Introduction: Biliary duct injury (BDI) is a serious complication during cholecystectomy. Perioperative cholangiography (POC) has recently been generating interest in order to prevent BDI. However, the current literature (including randomized controlled trials) cannot conclude whether POC is protective or not against the risk of BDI. The aim of our study was to investigate whether POC could demonstrate earlier BDI and which criteria are required to make that diagnosis. Methods: We performed a retrospective study between 2005 and 2018 in our French tertiary referral center, which included all patients who had presented following BDI during cholecystectomy. Results: Twenty-two patients were included. Nine patients had POC, whereas 13 did not. When executed, POC was interpreted as normal for three patients and abnormal for six. In this latter group, only two cases had a BDI diagnosed intraoperatively. In other cases, the interpretation was not adequate. Conclusion: BDIs are rare but may reduce patients' quality of life. Our study highlights the surgeon's responsibility to learn how to perform and interpret POC in order to diagnose and manage BDIs and potentially avoid catastrophic consequences.

11.
Sci Rep ; 11(1): 4379, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33623063

RESUMEN

The introduction of biological or absorbable synthetic meshes has provided an alternative to conventional repair for incisional hernia. The ability to predict the development of complications after hernia surgery is important, as it guides surgical planning and patient management. This retrospective study assessed whether the postoperative C-reactive protein (CRP) level can predict complications after incisional hernia repair using biological mesh reinforcement. Patients who underwent incisional hernia repair surgery using biological meshes between February 2009 and February 2015 were screened for study inclusion. Patients included in the study were divided into two groups: those with and without postoperative complications. The two groups were analysed based on sex, surgical operation, length of intensive care unit stay (ICU), complications and mortality. Laboratory values, including white blood cell (WBC) count and CRP levels, were determined preoperatively and up to postoperative day (POD) 10. Postoperative complications requiring further management occurred in 32 of the 60 patients (53.3%). Among 47 patients, the mean CRP and WBC levels were 6.6 mg/L and 9.073 G/L in the group without complications vs. 141.0 mg/L, 16.704 G/L in the group with complications (p < 0.001). Patients with complications also had a longer ICU stay (10.1 vs. 0.6 days, p < 0.0001). A cut-off was 101 mg/L and offered 80.00% sensitivity (IC 61.43% to 92.29) and 95.24% specificity (76.18% to 99.88%) for postoperative complication. The rate of postoperative complications before POD10 was 95% in the group with CRP > 100 mg/L vs. 46% in the group with CRP < 100 mg/L (p = 0.000372). A high postoperative CRP level (> 100 mg/L) up to POD10 may serve as a predictor of postoperative complications in patients undergoing incisional hernia using biological meshes.


Asunto(s)
Proteína C-Reactiva/análisis , Herniorrafia/efectos adversos , Complicaciones Posoperatorias/epidemiología , Mallas Quirúrgicas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Herniorrafia/instrumentación , Herniorrafia/métodos , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/sangre
12.
Surg Endosc ; 35(2): 702-709, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32060746

RESUMEN

BACKGROUND: Biological acellular porcine dermis mesh, such as Permacol™, has been used since 2009 to treat abdominal incisional hernias in a septic context. This study investigated the risk factors for incisional hernia recurrence after biological mesh augmentation. RESULTS: Over a period of 6 years from February 2009 to February 2015, 68 patients underwent surgery. The mesh was placed intraperitoneally with closure of the anterior fascia in 27 cases (39.7%). The biological mesh was placed in the retromuscular pre-fascial plane in 1 case (1.5%) and pre-aponeurotic plane in 1 case (1.5%). Closure of the anterior fascia was not achieved in 39 cases, including 20 cases in which the mesh was placed intraperitoneally (intraperitoneal bridging group, 29.4%) and 19 cases in which the mesh was placed between the edges of the fascia (inlay bridging group, 27.9%). There were 37 cases of postoperative surgical site infections (54.4%), and Clavien-Dindo morbidity staging indicated stage I-II and III-IV complications in 19.1% and 44.1% of the cases, respectively. The recurrence rate was 61.8%, and the mortality rate was 0%. The rate of recurrence was significantly lower in the «fascia approximated¼ group (37%), p = 0.001). Univariate analyses of risk factors for procedural failure indicated an increased risk of recurrence in cases of postoperative surgical site infections, complications of Clavien-Dindo grade III or higher, an absent fascial closure in front of the mesh (OR = 8.69), an operating time longer than 180 min, and a VHWG score higher than 2. After logistic regression, the risk factors for recurrence were postoperative infections (OR = 6.2), placement of bridged biological mesh (OR = 22.3), and postoperative morbidity grade III or higher (OR = 16.7). CONCLUSIONS: Patients with postoperative surgical site infections are at an increased risk for recurrence, and bridged mesh placements lack efficacy. Overall, this study challenges the purported advantage of biologics in treating incisional hernia repairs.


Asunto(s)
Hernia Ventral/cirugía , Herniorrafia/métodos , Mallas Quirúrgicas/normas , Adulto , Anciano , Anciano de 80 o más Años , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Porcinos
13.
Evolution ; 74(12): 2681-2702, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33085081

RESUMEN

The skeleton is a complex arrangement of anatomical structures that covary to various degrees depending on both intrinsic and extrinsic factors. Among the Feliformia, many species are characterized by predator lifestyles providing a unique opportunity to investigate the impact of highly specialized hypercarnivorous diet on phenotypic integration and shape diversity. To do so, we compared the shape of the skull, mandible, humerus, and femur of species in relation to their feeding strategies (hypercarnivorous vs. generalist species) and prey preference (predators of small vs. large prey) using three-dimensional geometric morphometric techniques. Our results highlight different degrees of morphological integration in the Feliformia depending on the functional implication of the anatomical structure, with an overall higher covariation of structures in hypercarnivorous species. The skull and the forelimb are not integrated in generalist species, whereas they are integrated in hypercarnivores. These results can potentially be explained by the different feeding strategies of these species. Contrary to our expectations, hypercarnivores display a higher disparity for the skull than generalist species. This is probably due to the fact that a specialization toward high-meat diet could be achieved through various phenotypes. Finally, humeri and femora display shape variations depending on relative prey size preference. Large species feeding on large prey tend to have robust long bones due to higher biomechanical constraints.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Carnivoría/fisiología , Feliformes/anatomía & histología , Fenotipo , Esqueleto/anatomía & histología , Animales , Dieta
14.
Nat Ecol Evol ; 4(8): 1129-1140, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32572219

RESUMEN

Metamorphosis is widespread across the animal kingdom and induces fundamental changes in the morphology, habitat and resources used by an organism during its lifetime. Metamorphic species are likely to experience more dynamic selective pressures through ontogeny compared with species with single-phase life cycles, which may drive divergent evolutionary dynamics. Here, we reconstruct the cranial evolution of the salamander using geometric morphometric data from 148 species spanning the order's full phylogenetic, developmental and ecological diversity. We demonstrate that life cycle influences cranial shape diversity and rate of evolution. Shifts in the rate of cranial evolution are consistently associated with transitions from biphasic to either direct-developing or paedomorphic life cycle strategies. Direct-developers exhibit the slowest rates of evolution and the lowest disparity, and paedomorphic species the highest. Species undergoing complete metamorphosis (biphasic and direct-developing) exhibit greater cranial modularity (evolutionary independence among regions) than do paedomorphic species, which undergo differential metamorphosis. Biphasic and direct-developing species also display elevated disparity relative to the evolutionary rate for bones associated with feeding, whereas this is not the case for paedomorphic species. Metamorphosis has profoundly influenced salamander cranial evolution, requiring greater autonomy of cranial elements and facilitating the rapid evolution of regions that are remodelled through ontogeny. Rather than compounding functional constraints on variation, metamorphosis seems to have promoted the morphological evolution of salamanders over 180 million years, which may explain the ubiquity of this complex life cycle strategy across disparate organisms.


Asunto(s)
Metamorfosis Biológica , Urodelos , Animales , Estadios del Ciclo de Vida , Filogenia , Cráneo , Urodelos/genética
15.
Proc Natl Acad Sci U S A ; 117(19): 10429-10434, 2020 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-32341144

RESUMEN

Extreme climate events such as droughts, cold snaps, and hurricanes can be powerful agents of natural selection, producing acute selective pressures very different from the everyday pressures acting on organisms. However, it remains unknown whether these infrequent but severe disruptions are quickly erased by quotidian selective forces, or whether they have the potential to durably shape biodiversity patterns across regions and clades. Here, we show that hurricanes have enduring evolutionary impacts on the morphology of anoles, a diverse Neotropical lizard clade. We first demonstrate a transgenerational effect of extreme selection on toepad area for two populations struck by hurricanes in 2017. Given this short-term effect of hurricanes, we then asked whether populations and species that more frequently experienced hurricanes have larger toepads. Using 70 y of historical hurricane data, we demonstrate that, indeed, toepad area positively correlates with hurricane activity for both 12 island populations of Anolis sagrei and 188 Anolis species throughout the Neotropics. Extreme climate events are intensifying due to climate change and may represent overlooked drivers of biogeographic and large-scale biodiversity patterns.


Asunto(s)
Lagartos/anatomía & histología , Selección Genética/fisiología , Animales , Biodiversidad , Evolución Biológica , Clima , Cambio Climático/estadística & datos numéricos , Tormentas Ciclónicas/estadística & datos numéricos , Desastres/estadística & datos numéricos , Ecosistema , Islas , Filogenia , Filogeografía , Dinámica Poblacional/estadística & datos numéricos , Dedos del Pie/anatomía & histología
16.
Evolution ; 74(6): 1200-1215, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32346857

RESUMEN

Evolutionary integration (covariation) of traits has long fascinated biologists because of its potential to elucidate factors that have shaped morphological evolution. Studies of tetrapod crania have identified patterns of evolutionary integration that reflect functional or developmental interactions among traits, but no studies to date have sampled widely across the species-rich lissamphibian order Anura (frogs). Frogs exhibit a vast range of cranial morphologies, life history strategies, and ecologies. Here, using high-density morphometrics we capture cranial morphology for 172 anuran species, sampling every extant family. We quantify the pattern of evolutionary modularity in the frog skull and compare patterns in taxa with different life history modes. Evolutionary changes across the anuran cranium are highly modular, with a well-integrated "suspensorium" involved in feeding. This pattern is strikingly similar to that identified for caecilian and salamander crania, suggesting replication of patterns of evolutionary integration across Lissamphibia. Surprisingly, possession of a feeding larval stage has no notable influence on cranial integration across frogs. However, late-ossifying bones exhibit higher integration than early-ossifying bones. Finally, anuran cranial modules show diverse morphological disparities, supporting the hypothesis that modular variation allows mosaic evolution of the cranium, but we find no consistent relationship between degree of within-module integration and disparity.


Asunto(s)
Anuros/anatomía & histología , Evolución Biológica , Cráneo/anatomía & histología , Animales , Biometría , Osteogénesis
17.
Sci Rep ; 10(1): 3643, 2020 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-32107426

RESUMEN

Hartmann's reversal procedures are often fraught with complications or failure to recover. This being a fact, it is often difficult to select patients with the optimal indications for a reversal. The post-recovery morbidity and mortality rates in the literature are heterogeneous between 0.8 and 44%. The identification of predictive risk factors of failure of such interventions would therefore be very useful to help the practitioner in his approach. Given these elements, it was important to us to analyze the practice of two French university hospitals in order to highlight such risk factors and to allow surgeons to select the best therapeutic strategy. We performed a bicentric observational retrospective study between 2010 and 2015 that studied the characteristics of patients who had undergone Hartmann surgery and were subsequently reestablished. The aim of the study was to identify factors influencing morbidity and postoperative mortality of Hartmann's reversal. Primary outcome was complications within the first 90 postoperative days. 240 patients were studied of which 60.4% were men. The mean age was 69.48 years. The median time to reversal was 8 months. 79.17% of patients were operated as emergency cases where the indication was a diverticular complication (39.17%). Seventy patients (29.2%) underwent a reversal and approximately 43% of these had complications within the first 90 postoperative days. The mean age of these seventy patients was 61.3 years old and 65.7% were males. None of them benefited from a reversal in the first three months. We identified some risk factors for morbidity such as pre-operative low albuminemia (p = 0.005) and moderate renal impairment (p = 0.019). However, chronic corticosteroid use (p = 0.004), moderate renal insufficiency (p = 0.014) and coronary artery disease (p = 0.014) seem to favour the development of anastomotic fistula, which is itself, a risk factor for mortality (p = 0.007). Our study highlights an important rate of complications including significant anastomotic fistula after Hartmann's reversal. Precarious nutritional status and cardiovascular comorbidities should clearly lead us to reconsider the surgical indication for continuity restoration.


Asunto(s)
Colostomía/efectos adversos , Complicaciones Posoperatorias/mortalidad , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Femenino , Francia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
18.
PeerJ ; 7: e7932, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31799066

RESUMEN

Vertebrate osteological collections provide comparative material for morphological analysis. Before being stored in the collection and studied by researchers, specimens are treated by preparators or curators and are cleaned. The preparation protocol employed ideally should not damage the material. Here, we explore the potential deformation of bones due to preparation using geometric morphometric methods. We focus both on intraspecific and interspecific variability. Our data on the scapular girdle of birds show that, at an intraspecific level, the effect of preparation on bone shape cannot be neglected. Paired and unpaired bones did not respond to the preparation process in the same way, possibly due to differences in function and their anatomical characteristics. Moreover, deformations due to preparation can be estimated by looking at the texture of the bone. At the interspecific level, we found no significant differences as the deformations induced by preparation are relatively small compared to differences among species. This study highlights the importance of carefully selecting preparation methods in order to avoid physical damage that could impact the shape of bones, especially for studies at the intraspecific level.

19.
Ecol Evol ; 9(22): 12408-12420, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31788186

RESUMEN

Access to resources is a dynamic and multicausal process that determines the success and survival of a population. It is therefore often challenging to disentangle the factors affecting ecological traits like diet. Insular habitats provide a good opportunity to study how variation in diet originates, in particular in populations of mesopredators such as lizards. Indeed, high levels of population density associated with low food abundance and low predation are selection pressures typically observed on islands. In the present study, the diet of eighteen insular populations of two closely related species of lacertid lizards (Podarcis sicula and Podarcis melisellensis) was assessed. Our results reveal that despite dietary variability among populations, diet taxonomic diversity is not impacted by island area. In contrast, however, diet disparity metrics, based on the variability in the physical (hardness) and behavioral (evasiveness) properties of ingested food items, are correlated with island size. These findings suggest that an increase in intraspecific competition for access to resources may induce shifts in functional components of the diet. Additionally, the two species differed in the relation between diet disparity and island area suggesting that different strategies exist to deal with low food abundance in these two species. Finally, sexual dimorphism in diet and head dimensions is not greater on smaller islands, in contrast to our predictions.

20.
J Exp Biol ; 222(Pt 20)2019 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-31558589

RESUMEN

Manual grasping is widespread among tetrapods but is more prominent and dexterous in primates. Whether the selective pressures that drove the evolution of dexterous hand grasping involved the collection of fruit or predation on mobile insects remains an area of debate. One way to explore this question is to examine preferences for manual versus oral grasping of a moving object. Previous studies on strepsirrhines have shown a preference for oral grasping when grasping static food items and a preference for manual grasping when grasping mobile prey such as insects, but little is known about the factors at play. Using a controlled experiment with a simple and predictable motion of a food item, we tested and compared the grasping behaviours of 53 captive individuals belonging to 17 species of strepsirrhines while grasping swinging food items and static food items. The swinging motion increased the frequency of hand-use for all individuals. Our results provide evidence that the swinging motion of the food is a sufficient parameter to increase hand grasping in a wide variety of strepsirrhine primates. From an evolutionary perspective, this result gives some support to the idea that hand-grasping abilities evolved under selective pressure associated with the predation of food items in motion. Looking at a common grasping pattern across a large set of species, this study provides important insight into comparative approaches to understanding the evolution of the hand grasping of food in primates and potentially other tetrapod taxa.


Asunto(s)
Evolución Biológica , Alimentos , Fuerza de la Mano/fisiología , Primates/fisiología , Animales , Bases de Datos como Asunto , Femenino , Masculino , Modelos Biológicos , Movimiento
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