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1.
J Anim Ecol ; 91(12): 2358-2369, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36169598

RESUMEN

Background matching is perhaps the most ubiquitous form of defensive camouflage in the animal kingdom, an adaptive strategy that relies on the visual resemblance between a prey organism and its background to promote concealment from predators. The importance of background matching has been acknowledged for over a century, yet despite its renown and apparent pervasiveness, few studies exist that have objectively quantified its occurrence and tested the functional significance of background matching in a specific animal study system. The North Island lichen moth Declana atronivea presents a fascinating system to investigate such anti-predator coloration. This species possesses high contrast black and white forewings that appear to resemble lichen. Here we assessed the contribution of background matching to the antipredator defence of D. atronivea using field predation experiments with realistic models. We found that D. atronivea coloration confers a significant survival advantage against native avian predators when on lichen backgrounds compared to bark backgrounds, with an intermediate level of predation occurring when models were near, but not on lichen. This suggests that D. atronivea wing patterns are an adaptation for background matching. We subsequently used calibrated digital photography, avian vision modelling and image analysis techniques to objectively quantify the degree of background matching exhibited by D. atronivea and assessed the contribution of different visual elements (colour, luminance and pattern) to camouflage in this species. Only the pattern elements of D. atronivea presented a close match to that of the lichen backgrounds, with both chromatic and achromatic cues found to be poor predictors of background matching in this species. This study is one of the first to integrate vision modelling, quantitative image analysis and field predation experiments using realistic models to objectively quantify the level and functional significance of background matching in a real species, and presents an ideal system for further investigating the interrelation between multiple mechanisms of camouflage.


Asunto(s)
Líquenes , Mariposas Nocturnas , Animales
2.
J Card Surg ; 36(3): 1050-1055, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33336415

RESUMEN

BACKGROUND: Subxiphoid incisional hernias are one of the complications following a median sternotomy, a surgical procedure to provide access to the mediastinum. Incidence has been reported between 1% and 4%, although the true incidence is not well known due to its asymptomatic nature. METHOD: A comprehensive search was performed on multiple sites. Keywords included "incisional hernia OR Subxiphoid hernia" AND "Median sternotomy OR Cardiac Surgery OR Coronary artery bypass graft OR Transplant OR Valve replacement". Articles up to August 1, 2020, were included in this study. RESULTS: Eight articles were included in the study, with a total number of 132 patients identified. The incidence ranged from 0.81% to 3.44%. There was a mixture of repair methods and follow-up period reported. Recurrence post repair ranged from 10% to 43%. CONCLUSION: Subxiphoid incisional hernias remain challenging to manage. We have discussed the incidence, risk factors, preventions, and management of subxiphoid incisional hernias including both the open and laparoscopic techniques.


Asunto(s)
Hernia Ventral , Hernia Incisional , Laparoscopía , Hernia Ventral/cirugía , Humanos , Hernia Incisional/epidemiología , Hernia Incisional/cirugía , Complicaciones Posoperatorias/epidemiología , Recurrencia , Esternotomía , Mallas Quirúrgicas
3.
Proc Biol Sci ; 287(1934): 20201016, 2020 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-32873210

RESUMEN

Anti-predator defences are typically regarded as relatively static signals that conceal prey or advertise their unprofitability. However, startle displays are complex performances that deter or confuse predators and can include a spectacular array of movements, colours and sounds. Yet, we do not fully understand the mechanisms by which they function, their evolutionary correlates, or the conditions under which they are performed and evolve. Here, we present, to our knowledge, the first phylogenetically controlled comparative analyses of startle displays including behavioural data, using praying mantises as a model system. We included 58 species that provide a good representation of mantis diversity and estimated the strength of phylogenetic signal in the presence and complexity of displays. We also tested hypotheses on potential evolutionary correlates, including primary defences and body size. We found that startle displays and morphological traits were phylogenetically conserved, whereas behavioural traits were highly labile. Surprisingly, body size was not correlated with display presence or complexity in phylogenetically controlled analyses. Species-rich clades were more likely to exhibit displays, suggesting that startle displays were probably involved in lineage diversification. We suggest that to further elucidate the conditions under which startle displays evolve, future work should include quantitative descriptions of multiple display components, habitat type, and predator communities. Understanding the evolution of startle displays is critical to our overall understanding of the theory behind predator-prey dynamics.


Asunto(s)
Evolución Biológica , Mantódeos/fisiología , Animales , Tamaño Corporal , Filogenia , Conducta Predatoria
4.
Naturwissenschaften ; 107(4): 34, 2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32737596

RESUMEN

The egg stages of animal life cycles are underappreciated in terms of their capacity for dispersal, protection, and biotic and abiotic interactions. Some of the most intriguing egg morphologies are seen in stick and leaf insects (Phasmatodea). Phasmids are charismatic insects, particularly due to their incredible camouflage, though a lesser-known fact is that their eggs are incredibly diverse in shape and structure, reflecting varying ecological niches. Perhaps most remarkable are those eggs which appear to resemble plant seeds in both their appearance and means of dispersal, such as via water and animal vectors. Numerous hypotheses surrounding the function of these egg morphologies and their apparent convergence with seeds have been proposed; however, empirical evidence remains lacking. Here, we present an initial synthesis of available evidence surrounding the ecology and dispersal strategies of phasmid eggs and weigh up the evidence for convergent evolution between phasmid eggs and seeds. In doing so, we highlight areas where further research is needed and discuss how the ecology of phasmid eggs may interplay with other aspects of phasmid ecology, distribution, and evolution.


Asunto(s)
Evolución Biológica , Neoptera/clasificación , Neoptera/fisiología , Plantas/anatomía & histología , Plantas/clasificación , Semillas/anatomía & histología , Cigoto/citología , Distribución Animal/fisiología , Animales
5.
Naturwissenschaften ; 105(1-2): 3, 2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-29209865

RESUMEN

Male reproductive performance can vary with condition, age and future reproductive opportunities. Web-building spiders are ideal models to examine the effects of senescence on fitness-related behaviours due to strong selection on male courtship to reduce pre-copulatory sexual cannibalism. Argiope keyserlingi spiders generate courtship vibrations, or 'shudders', that reduce female aggression. We found that male A. keyserlingi courtship slowed with chronological age. Older males took longer to travel across the courtship thread, and overall number of shudders increased. Males retained some ability to modulate courtship quality (shudder duration and number of rocks within each shudder) in response to female quality. A change in courtship performance over time, despite strong selection for repeatability, indicates that ageing in male A. keyserlingi may have direct impacts on reproductive performance.


Asunto(s)
Conducta Sexual Animal/fisiología , Arañas/fisiología , Envejecimiento , Animales , Femenino , Masculino , Reproducción/fisiología , Factores de Tiempo , Vibración
6.
J Chem Ecol ; 41(8): 689-95, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26245262

RESUMEN

Numerous tree species' seeds contain an 'elaiosome' that acts as a food reward for ants and thus induces dispersal of the seeds. Many stick and leaf insect species appear to have evolved a convergent adaptation for dispersal whereby the egg 'capitulum' serves to induce ants to pick up and carry their eggs. Here, we investigated whether the capitulum facilitates egg dispersal by ants in the Australian stick insect Eurycnema goliath. The total fatty acid composition of E. goliath egg capsules and egg capitula were characterized to identify potential signaling compounds. Removing capitula from E. goliath eggs significantly reduced the likelihood of eggs being carried into the nests of Rhytidoponera metallica ants. Furthermore, attaching capitula to inert objects (polystyrene balls) resulted in these objects being carried into nests by R. metallica. Several fatty acids were present on the egg capsule surface in only trace amounts, whereas they made up over 10% of the dry weight of egg capitula. The fatty acid composition of egg capitula consisted mostly of palmitic acid (C16:0), linoleic acid (C18: 2n6c), oleic acid (C18:1n9c), linolenic acid (C18:3n3), and stearic acid (C18:0). Previously reported research has found that a diglyceride lipid species of oleic acid induces carrying behavior in R. metallica when added to inert artificial stimuli. Therefore, we propose that the dispersal mechanism of E. goliath eggs has converged upon the same chemical signaling pathway used by plants to exploit ant behavior.


Asunto(s)
Distribución Animal , Ácidos Grasos/análisis , Insectos/química , Insectos/fisiología , Óvulo/química , Animales , Hormigas/fisiología , Conducta Apetitiva , Australia , Evolución Biológica , Señales (Psicología) , Magnoliopsida/fisiología , Simbiosis
7.
Am Nat ; 183(1): 126-32, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24334741

RESUMEN

Mimicry has evolved in contexts such as camouflage, predator deterrence, luring of prey, and pollinator attraction. Mimicry of flowers has until now been demonstrated only in angiosperms, yet it has been hypothesized that the Malaysian orchid mantis Hymenopus coronatus mimics a flower to attract pollinators as prey. Despite the popularity of this charismatic insect, this long-discussed hypothesis has never been experimentally investigated. We found that, as predicted for mimicry, the color of H. coronatus is indistinguishable from the color of sympatric flowers for hymenopteran pollinators. Field experiments show that isolated mantises attract wild pollinators at a rate even higher than flowers and capture these pollinators as prey items. After more than a century of conjecture, we provide the first experimental evidence of pollinator deception in the orchid mantis and the first description of a unique predatory strategy that has not been documented in any other animal species.


Asunto(s)
Adaptación Biológica , Insectos/fisiología , Animales , Conducta Animal , Color , Femenino , Flores , Orchidaceae , Polinización
8.
Front Public Health ; 12: 1398104, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39035186

RESUMEN

Background: The application of nanomaterials (NMs) and nano-enabled products (NEPs) across many industries has been extensive and is still expanding decades after first being identified as an emerging technology. Additive manufacturing has been greatly impacted and has seen the benefits of integrating NMs within products. With the expansion of nanotechnology, there has been a need to develop more adaptive and responsive methods to ascertain risks and ensure technology is developed safely. The Safe(r)-by-Design (SbD) concept can be used to establish safe parameters and minimise risks during the materials' lifecycle, including the early stages of the supply chain. Exposure monitoring has advanced in recent years with the creation of standardised protocols for occupational exposure assessment of nano-objects and their aggregates and agglomerates (NOAA). Methods: To aid in the development of an online SbD-supporting platform by the EU-funded project SAbyNA, we adopt a Europe Standard for monitoring release of NOAA to identify if a greater release of NOAA is associated with incorporation of NMs within NEPs compared to a polymer matrix alone. Case studies included filaments of polypropylene (PP) with nano-Ag or polycarbonate (PC) with single-walled carbon nanotubes (SWCNTs). NMs were received in masterbatch, and therefore previously modified to align with SbD interventions. Results were collected in line with European Standard recommendations: monitoring particle concentrations using direct reading instruments (DRI), sampling for offline chemical and morphological analysis, and collecting contextual information. Results and discussion: Based on the criteria described in the European standard (BS EN 17058), data from both case studies identified that inhalation exposure relating to NM was "unlikely". Despite this, during the production of the SWCNT-PC filaments, some noteworthy observations were made, including several DRI activity measurements shown to be higher than background levels, and material morphologically similar to the reference SWCNT/polymeric masterbatch observed in offline analysis. The data collected during this campaign were used to discuss choices available for data interpretation and decision-making in the European Standard for monitoring release of NOAA and also to facilitate the development of SAbyNA's user-friendly industry platform for the SbD of NMs and NEPs.


Asunto(s)
Nanoestructuras , Exposición Profesional , Exposición Profesional/prevención & control , Humanos , Monitoreo del Ambiente , Nanotecnología , Polipropilenos , Europa (Continente) , Cemento de Policarboxilato/química , Plásticos , Nanotubos de Carbono
9.
Curr Biol ; 34(1): 183-189.e4, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38035884

RESUMEN

To glide in forest canopies, arboreal vertebrates evolved various skin-derived aerodynamic structures, such as patagial membranes or webbing, but no comparable structure has been reported from wingless arboreal arthropods.1,2,3 Orchid mantises (Hymenopus coronatus) have been traditionally considered a textbook example of flower mimicry for ∼200 years due to their highly expanded, petal-shaped femoral lobes. However, the empirical evidence substantiating the petal-mimicry function of the femoral lobes has not been entirely conclusive.4,5,6 Observational and experimental evidence suggests that these lobes do not contribute to flower mimicry for luring pollinators6,7 and likely serve other functions.7,8 After observing their aerial escape initiated with active jumping, we hypothesized that orchid mantises can glide and that their femoral lobes are used for gliding. Through behavioral investigations and morphological analyses, we show that orchid mantis nymphs are excellent gliders, exhibiting the shallowest gliding trajectories observed in terrestrial invertebrates.9,10,11,12,13 The lobe extensions on their femoral segments are cambered airfoils, which increase the mantis projected area by ∼36% and play a vital role in the aerodynamic underpinning of the observed gliding. Despite a 165-fold increase in body mass throughout ontogeny, older female mantis nymphs maintained a persistent gliding capability. We further showed a notable 40%-56% reduction in wing loading attributed to the positive size allometry of these lobes, indicating a clear promotion of gliding throughout ontogeny. This is the first documentation of gliding-adapted "leg wings" in a wingless arthropod. The evolution of such structures is potentially common among arboreal arthropods and demands a systematic re-examination.


Asunto(s)
Vuelo Animal , Mantódeos , Femenino , Animales , Fenómenos Biomecánicos , Bosques , Árboles
10.
Artículo en Inglés | MEDLINE | ID: mdl-36612588

RESUMEN

We provide a narrative review on the published peer-reviewed scientific literature reporting sampler efficiency, performance and comparison studies (where two or more samplers have been assessed) in laboratory settings published between 1994 and 2021 (27 year period). This review is a follow-up to our narrative review on the published peer-reviewed scientific literature reporting sampler comparison in workplace settings. Search terms were developed for Web of Science and PubMed bibliographic databases. The retrieved articles were then screened for relevance, with those studies meeting the inclusion criteria being taken forward to data extraction (25 studies). The most common fraction assessed has been the inhalable fraction, with the IOM sampler being the most studied inhalable sampler and the SKC Aluminium cyclone being the most studied respirable sampler from the identified relevant articles. The most common aerosol used has been aluminium oxide. It was evident that standardisation for these sampler performance experiments is lacking. It was not possible to identify any discernible trends for the performance of samplers when assessed with different aerosols. The need for more detailed and informative data sharing from authors is highlighted. This includes provision of clear identifiable information on the samplers used for testing, sampler flow rates (both manufacturer and those actually used in the study, with an explanation given of any differences), detailed information on the test aerosols used and the sampler substrate materials used. An identified gap in the literature is the potential to perform studies aimed at revaluating the performance of samplers to allow any longer-term temporal changes in performance to be assessed. One approach in advancing the field is to produce an updated protocol for the laboratory testing of samplers. This updated protocol would be beneficial for both the research and occupational hygiene community and would allow harmonised assessment and reporting of sampler comparison studies.


Asunto(s)
Contaminantes Ocupacionales del Aire , Exposición Profesional , Exposición Profesional/análisis , Monitoreo del Ambiente/métodos , Tamaño de la Partícula , Aerosoles/análisis , Lugar de Trabajo , Contaminantes Ocupacionales del Aire/análisis , Exposición por Inhalación/análisis , Polvo/análisis
11.
J Urban Hist ; 37(5): 732-56, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22073437

RESUMEN

In this article, the author uses a slum clearance project in Lexington, Kentucky, as a lens through which to examine the spatial dynamics of racial residential segregation during the first half of the twentieth century. At the time, urban migration and upward socioeconomic mobility on the part of African Americans destabilized extant residential segregation patterns. Amid this instability, various spatial practices were employed in the interest of maintaining white social and economic supremacy. The author argues that such practices were indicative of a thoroughgoing reinvention of urban socio-spatial order that in turn precipitated the vastly expanded scale of residential segregation still found in U.S. cities today. Evidence of this reinvented ordering of urban space lies in the rendering of some long-standing African American neighborhoods as "out of place" within it and the use of slum clearance to remove the "menace" such neighborhoods posed to it.


Asunto(s)
Áreas de Pobreza , Prejuicio , Características de la Residencia , Problemas Sociales , Población Urbana , Remodelación Urbana , Historia del Siglo XX , Historia del Siglo XXI , Kentucky/etnología , Dinámica Poblacional/historia , Relaciones Raciales/historia , Relaciones Raciales/legislación & jurisprudencia , Relaciones Raciales/psicología , Características de la Residencia/historia , Aislamiento Social/psicología , Problemas Sociales/economía , Problemas Sociales/etnología , Problemas Sociales/historia , Problemas Sociales/legislación & jurisprudencia , Problemas Sociales/psicología , Factores Socioeconómicos/historia , Población Urbana/historia , Remodelación Urbana/economía , Remodelación Urbana/educación , Remodelación Urbana/historia , Remodelación Urbana/legislación & jurisprudencia
12.
Artículo en Inglés | MEDLINE | ID: mdl-34202035

RESUMEN

We provide a narrative review on published peer-reviewed scientific literature reporting comparisons of personal samplers in workplace settings published between 2004 and 2020. Search terms were developed for Web of Science and PubMed bibliographic databases. The retrieved studies were then screened for relevance, with those studies meeting the inclusion criteria being taken forward to data extraction (22 studies). The inhalable fraction was the most common fraction assessed with the IOM sampler being the most studied sampler. The most common workplace environment where samplers had been compared was that where metals/metalloids were present. The requirements of EN13205 standard (Workplace exposure. Assessment of sampler performance for measurement of airborne particle concentrations) have also been considered, with these requirements not currently being met, or at least referred to, in the included published literature. A number of conclusions have been drawn from this narrative review. For studies that reported correction factors, no discernible trends could be identified. Correction factors also varied between samplers and settings, with correction factors varying from 0.67 for Button/IOM in agriculture settings to a correction factor of 4.2 for the closed face cassette/IOM samplers in aluminium smelters. The need for more detailed and informative data sharing from authors is highlighted, providing more context to both the sampling strategy and methodology, as well as the data analysis. It is recommended that the requirements of EN13205 are taken into account when designing sampler comparison studies at the workplace and that these are also reported. It is also considered that there is a need for a clear standardized workplace sampler comparison protocol to be developed, which can be used by the research and occupational hygiene community to allow more robust and transparent assessment of aerosol samplers and better-quality evidence for use by industrial hygienists, epidemiologists, and occupational safety specialists alike.


Asunto(s)
Contaminantes Ocupacionales del Aire , Exposición Profesional , Aerosoles/análisis , Contaminantes Ocupacionales del Aire/análisis , Polvo , Monitoreo del Ambiente , Exposición por Inhalación/análisis , Exposición Profesional/análisis , Tamaño de la Partícula , Lugar de Trabajo
13.
Org Lett ; 21(18): 7289-7293, 2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31497960

RESUMEN

The preparation of a new series of dihydridoboranes supported by N,N-chelating ligands, [R2NCH2CH2NAr]- (R = alkyl, Ar = aryl), is reported. These new boranes react selectively with carbonyls, imines, and a series of electron-deficient fluoroarenes. The reactivity is complementary to recognized reagents such as pinacolborane, catecholborane, NHC-BH3, and borane (BH3) itself. Selectivities are rationalized by invoking both open- and closed-chain forms of the reagents as part of equilibrium mixtures.

14.
J Biomol Screen ; 11(8): 933-9, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17092919

RESUMEN

Many companies possess a compound collection consisting of purified compounds and of unpurified products from combinatorial libraries. Using commercial and proprietary compounds as examples, this report provides clear examples of the significant impact purification can have on the activity observed for a compound and highlights the need to retest the purified compounds prior to creating structure-activity relationships. Crude mixtures made with commercial compounds led to an increase in the number of false positives in the SXR-GAL4 assay as compared with their pure and purified counterparts. An examination of proprietary compounds in an HIV assay resulted in the purification of 61 active crude synthetic mixtures. Of these 61 compounds, 32 were 5-fold less active and 2 were 5-fold more active after purification. This report details a semiautomated process developed and implemented for cherry-picking, tracking, and selectively purifying compounds found active in high-throughput screening campaigns.


Asunto(s)
Técnicas Químicas Combinatorias , Evaluación Preclínica de Medicamentos/métodos , Cromatografía Liquida , Diseño de Fármacos , Reacciones Falso Positivas , Espectrometría de Masas , Manejo de Especímenes
15.
Curr Biol ; 26(4): R145-6, 2016 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-26906480

RESUMEN

James O'Hanlon introduces the orchid mantis, a species of preying mantis that resembles flowers.


Asunto(s)
Mimetismo Biológico , Flores , Insectos/anatomía & histología , Insectos/fisiología , Orchidaceae , Distribución Animal , Animales , Asia
16.
Sci Rep ; 6: 37753, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27905469

RESUMEN

Here we reconstruct the evolutionary shift towards floral simulation in orchid mantises and suggest female predatory selection as the likely driving force behind the development of extreme sexual size dimorphism. Through analysis of body size data and phylogenetic modelling of trait evolution, we recovered an ancestral shift towards sexual dimorphisms in both size and appearance in a lineage of flower-associated praying mantises. Sedentary female flower mantises dramatically increased in size prior to a transition from camouflaged, ambush predation to a floral simulation strategy, gaining access to, and visually attracting, a novel resource: large pollinating insects. Male flower mantises, however, remained small and mobile to facilitate mate-finding and reproductive success, consistent with ancestral male life strategy. Although moderate sexual size dimorphisms are common in many arthropod lineages, the predominant explanation is female size increase for increased fecundity. However, sex-dependent selective pressures acting outside of female fecundity have been suggested as mechanisms behind niche dimorphisms. Our hypothesised role of predatory selection acting on females to generate both extreme sexual size dimorphism coupled with niche dimorphism is novel among arthropods.


Asunto(s)
Evolución Biológica , Mantódeos/fisiología , Conducta Predatoria , Selección Genética , Caracteres Sexuales , Animales , Teorema de Bayes , Tamaño Corporal , Femenino , Masculino , Filogenia , Polinización , Análisis de Regresión , Reproducción
17.
Ecol Evol ; 5(4): 914-20, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25750717

RESUMEN

Sexually selected ornaments and signals are costly to maintain if they are maladaptive in nonreproductive contexts. The jumping spider Cosmophasis umbratica exhibits distinct sexual dichromatism with males displaying elaborate UV body markings that signal male quality. Female C. umbratica respond favorably to UV-reflecting males and ignore males that have their UV masked. However, Portia labiata, a UV-sensitive spider-eating specialist and a natural predator of C. umbratica, is known to use UV reflectance as a cue when hunting prey. We investigated the cost of these UV signals in C. umbratica in terms of their predation risk. Under experimental conditions, three choice scenarios were presented to P. labiata individuals. Choices by P. labiata were made between male C. umbratica with and without the UV signal; a UV-reflecting male and non-UV-reflecting female; and a UV-masked male and female. The presence and absence of UV signals was manipulated using an optical filter. Portia labiata exhibited a strong bias toward UV+ individuals. These results suggest the sexually selected trait of UV reflectance increases the visibility of males to UV-sensitive predators. The extent of this male-specific UV signal then is potentially moderated by predation pressure. Interestingly though, P. labiata still preferred males to females irrespective of whether UV reflectance was present or not. This suggests P. labiata can switch cues when conditions to detect UV reflectance are not optimal.

18.
PLoS One ; 10(6): e0128755, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26107629

RESUMEN

Genital asymmetry is relatively common and widespread throughout the animal kingdom. The functional significance of genital asymmetry is however, poorly understood for most species. Male praying mantids of the genus Ciulfina are remarkable in possessing complex and directionally asymmetric genital phallomeres in some species, and chirally dimorphic/antisymmetric genitalia in others. Here we explore the chiral dimorphism in male genitalia of Ciulfina baldersoni which appear to exhibit genital antisymmetry. We test whether genital orientation influences mating success, copulation duration and the attachment duration of spermatophores. Additionally we investigate genital interactions between male and females using x-ray micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). Lastly we assess whether genital asymmetry is associated with non-genital morphological asymmetry of a range of traits. Our results highlight the complex functional morphology of genitalia in this praying mantis species and yet demonstrate no functional difference between dextral and sinistral morphs other than the direction of attachment with both morphs enjoying equal levels of mating success. Chiral morphs also did not strongly associate with any other forms of asymmetry. We therefore conclude that genital chirality in Ciulfina baldersoni is a likely case of antisymmetry with no functional significance to genital orientation, and is likely to be selectively neutral.


Asunto(s)
Copulación/fisiología , Aptitud Genética/fisiología , Mantódeos/fisiología , Espermatogonias/fisiología , Animales , Femenino , Masculino , Mantódeos/ultraestructura , Reproducción/fisiología , Caracteres Sexuales , Espermatogonias/ultraestructura
19.
J Psychopharmacol ; 16(1): 57-64, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11949773

RESUMEN

Emedastine is registered in its country of origin (Japan) as an antihistamine for the indication of seasonal allergic rhinitis. Further research on the drug's sedating properties was needed to secure its registration elsewhere. The present study was designed to compare the effects of emedastine 2 mg and 4 mg twice daily after single and repeated doses, on actual driving performance versus those of cetirizine 10 mg once daily and placebo; and to determine how repeated doses of each drug interact with alcohol to affect driving. Each treatment was administered for 5 days to 19 healthy volunteers (nine men and ten women, aged 21-45 years) according to a four-period double-blind cross-over design. Driving performance was measured in a standardized test between 3 and 4 h after administration of the morning dose on days 1, 4 and 5. Alcohol, sufficient for achieving a blood alcohol concentration of 0.05 g/dl was given before driving on day 5 of each period. Both emedastine doses similarly and significantly impaired driving in every test. The effects of cetirizine were less. They were significant over days 1, 4 and 5 combined, although not separately. Women were more impaired by both drugs. Alcohol increased driving impairment similarly in every condition. Subjects were only able to discriminate the sedating and impairing effects of the first dose of emedastine 4 mg from placebo. Emedastine, in oral doses of 2 mg and 4 mg twice daily, is sedating and impairs driving. The drug could therefore constitute a traffic hazard and its users should be warned accordingly.


Asunto(s)
Conducción de Automóvil , Bencimidazoles/efectos adversos , Depresores del Sistema Nervioso Central/efectos adversos , Cetirizina/efectos adversos , Etanol/efectos adversos , Antagonistas de los Receptores Histamínicos H1/efectos adversos , Adulto , Afecto/efectos de los fármacos , Atención/efectos de los fármacos , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Interacciones Farmacológicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/efectos de los fármacos , Fases del Sueño/efectos de los fármacos
20.
Int Clin Psychopharmacol ; 18(2): 117-9, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12598825

RESUMEN

We report the case of a 23-year-old woman with velocardiofacial syndrome (VCFS) and a history of psychosis and seizures. She had been treated with conventional antipsychotic and antiepileptic drugs for 10 and 3 years, respectively. However, she continued to experience occasional hallucinations and paroxysmal jerking of the extremities. L-alpha-methyldopa 500 mg b.i.d. (later reduced to 250 mg t.i.d.) was added to her regimen. Hallucinations and seizures stopped shortly. Over the course of approximately 1 year, the previous medications were discontinued without recurrence of psychotic and epileptic symptoms. Eventually, improved mental functions and behaviour enabled her transition from living in a licensed residential facility to sharing a private residence with a partner. VCFS is associated with haploinsufficiency of catecholamine-methyltransferase, leading to excessive extraneuronal catecholamine concentrations. Alpha-Methyldopa inhibits catecholamine neurotransmission in a variety of ways. It is possible that the drug compensated for genetically disturbed catecholamine transmission thus achieving beneficial effects in this case.


Asunto(s)
Anomalías Múltiples/genética , Agonistas alfa-Adrenérgicos/uso terapéutico , Anticonvulsivantes/uso terapéutico , Antipsicóticos/uso terapéutico , Anomalías Craneofaciales/genética , Metildopa/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Adulto , Femenino , Humanos , Fenotipo , Trastornos Psicóticos/genética , Convulsiones/tratamiento farmacológico , Convulsiones/genética , Síndrome
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