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1.
PLoS One ; 18(7): e0285656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494328

RESUMO

Sexual selection often shapes social behavioural activities, such as movement in the environment to find possible partners, performance of displays to signal dominance and courtship behaviours. Such activities may be negatively influenced by increasing temperatures, especially in ectotherms, because individuals either have to withstand the unfavourable condition or are forced to allocate more time to thermoregulation by increasing shelter seeking behaviour. Thus, they "miss" opportunities for social and reproductive interactions. Moreover, behavioural displays of ectotherms closely depend on temperature; consequently, mate choice behaviours may be disrupted, ultimately modifying sexual selection patterns. Therefore, it would be interesting to elucidate how increasing temperatures associated with global warming may influence activity and social interactions in the species' natural habitat and, specifically how high temperatures may modify intersexual interactions. Consequently, our aim was to explore differences in the daily pattern of social interactions in an ectotherm model, Tropidurus spinulosus, in two thermally different habitats and to determine how high temperatures modify mate choice. High environmental temperatures were found to be associated with a bimodal pattern in daily activity, which was closely linked to the daily variations in the thermal quality of the habitat; whereas the pattern and frequency of social displays showed less plasticity. The time allocated to mate choice generally decreased with increasing temperature since individuals increased the use of thermal refuges; this result supports the hypothesis of "missed opportunities". Moreover, at high temperatures, both sexes showed changes in mate selection dynamics, with females possibly "rushing" mate choice and males showing an increase in intermale variability of reproductive displays. In our ectotherm model, plastic adjustments in the behavioural activity pattern induced by high temperatures, plus the modification of the displays during courtship may ultimately modify mate choice patterns and sexual selection dynamics.


Assuntos
Lagartos , Humanos , Animais , Masculino , Feminino , Temperatura , Temperatura Alta , Regulação da Temperatura Corporal , Corte
2.
Medicina (B.Aires) ; 81(2): 191-197, June 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1287270

RESUMO

Abstract Cardiovascular disorders represent the leading cause of death in dialysis patients. Alterations of bone and mineral metabolism (BMM) and vascular calcifications play a fundamental role in it. The objective of this study was to evaluate the predictive role on cardiovascular mortality of the measurement of biomarkers of BMM and vascular calcifications. A prospective cohort study was performed. All prevalent patients on chronic dialysis in September 2009 at our institution, who completed the total of the complementary stud ies, were studied. BMM biomarkers were measured (FGF 23, fetuin A, PTH, calcium and phosphorus) and the vascular calcifications were evaluated using the Kauppila and Adragao scores. Follow-up was carried out until 1/1/2019, death or transplant. Of the 30 patients included, 7 (23.3%) died due to cardiovascular causes. The follow-up time was 44.1 ± 30.4 (range = 1.4-112) months. The Adragao score was the only predictive variable of long-term cardiovascular mortality (area under the curve = 0.82; 95% CI 0.64-0.94; p < 0.001). The best cut-off point was 5 (sensitivity = 85.7%; specificity = 78.3%). It was also an independent risk factor for cardiovascular mortality adjusted for age, diabetes mellitus, coronary heart disease, aortic calcifications, time spent on dialysis and follow-up time (adjusted OR = 1.77; 95% CI = 1.06-2.96; p = 0.028). The vascular calcifications quantified from the Adragao score were the only independent predictor of long-term cardiovascular mortality. This score represents a simple, useful and superior tool to the biomarkers of BMM.


Resumen Los trastornos cardiovasculares representan la primera causa de muerte en los pacientes en diálisis. Las alteraciones del metabolismo óseo y mineral (MOM) y las calcificaciones vasculares juegan un papel fundamental en la misma. El objetivo de este estudio fue evaluar el rol predictor sobre la mortalidad car diovascular de la medición de los biomarcadores del MOM y las calcificaciones vasculares. Se realizó un estudio de cohorte prospectivo. Se estudiaron todos los pacientes prevalentes en diálisis crónica en septiembre del 2009 en nuestra institución que completaron el total de los estudios complementarios. Se midieron biomarcadores del MOM (FGF 23, fetuína A, PTH, calcio y fósforo) y se evaluaron las calcificaciones vasculares mediante los scores de Kauppila y de Adragao. Se realizó un seguimiento hasta el 1/1/2019, la muerte o el trasplante. De los 30 pacientes incluidos, 7 (23.3%) fallecieron por causa cardiovascular. El tiempo de seguimiento fue de 44.1 ± 30.4 (rango = 1.4-112) meses. El score de Adragao fue la única variable predictiva de muerte cardiovascular a largo plazo (área bajo la curva = 0.82; IC95% = 0.64-0.94; p<0.001). El mejor punto de corte fue de 5 (sensibili dad = 85.7%; especificidad = 78.3%). Además, fue un factor de riesgo independiente de muerte cardiovascular ajustado por edad, diabetes mellitus, enfermedad coronaria, calcificaciones aorticas, tiempo de permanencia en diálisis y tiempo de seguimiento (OR ajustado = 1.77; IC95% = 1.06-2.96; p = 0.028). Las calcificaciones vasculares cuantificadas a partir del score de Adragao fueron el único predictor independiente de mortalidad cardiovascular a largo plazo. Este score representa una herramienta simple, útil y superior a los biomarcadores del MOM.


Assuntos
Humanos , Calcificação Vascular , Falência Renal Crônica , Biomarcadores , Estudos Prospectivos , Seguimentos , Diálise Renal , alfa-2-Glicoproteína-HS , Minerais
3.
Medicina (B Aires) ; 81(2): 191-197, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33906137

RESUMO

Cardiovascular disorders represent the leading cause of death in dialysis patients. Alterations of bone and mineral metabolism (BMM) and vascular calcifications play a fundamental role in it. The objective of this study was to evaluate the predictive role on cardiovascular mortality of the measurement of biomarkers of BMM and vascular calcifications. A prospective cohort study was performed. All prevalent patients on chronic dialysis in September 2009 at our institution, who completed the total of the complementary studies, were studied. BMM biomarkers were measured (FGF 23, fetuin A, PTH, calcium and phosphorus) and the vascular calcifications were evaluated using the Kauppila and Adragao scores. Follow-up was carried out until 1/1/2019, death or transplant. Of the 30 patients included, 7 (23.3%) died due to cardiovascular causes. The follow-up time was 44.1 ± 30.4 (range = 1.4-112) months. The Adragao score was the only predictive variable of long-term cardiovascular mortality (area under the curve = 0.82; 95% CI 0.64-0.94; p < 0.001). The best cut-off point was 5 (sensitivity = 85.7%; specificity = 78.3%). It was also an independent risk factor for cardiovascular mortality adjusted for age, diabetes mellitus, coronary heart disease, aortic calcifications, time spent on dialysis and follow-up time (adjusted OR = 1.77; 95% CI = 1.06-2.96; p = 0.028). The vascular calcifications quantified from the Adragao score were the only independent predictor of long-term cardiovascular mortality. This score represents a simple, useful and superior tool to the biomarkers of BMM.


Los trastornos cardiovasculares representan la primera causa de muerte en los pacientes en diálisis. Las alteraciones del metabolismo óseo y mineral (MOM) y las calcificaciones vasculares juegan un papel fundamental en la misma. El objetivo de este estudio fue evaluar el rol predictor sobre la mortalidad cardiovascular de la medición de los biomarcadores del MOM y las calcificaciones vasculares. Se realizó un estudio de cohorte prospectivo. Se estudiaron todos los pacientes prevalentes en diálisis crónica en septiembre del 2009 en nuestra institución que completaron el total de los estudios complementarios. Se midieron biomarcadores del MOM (FGF 23, fetuína A, PTH, calcio y fósforo) y se evaluaron las calcificaciones vasculares mediante los scores de Kauppila y de Adragao. Se realizó un seguimiento hasta el 1/1/2019, la muerte o el trasplante. De los 30 pacientes incluidos, 7 (23.3%) fallecieron por causa cardiovascular. El tiempo de seguimiento fue de 44.1 ± 30.4 (rango = 1.4-112) meses. El score de Adragao fue la única variable predictiva de muerte cardiovascular a largo plazo (área bajo la curva = 0.82; IC95% = 0.64-0.94; p < 0.001). El mejor punto de corte fue de 5 (sensibilidad = 85.7%; especificidad = 78.3%). Además, fue un factor de riesgo independiente de muerte cardiovascular ajustado por edad, diabetes mellitus, enfermedad coronaria, calcificaciones aorticas, tiempo de permanencia en diálisis y tiempo de seguimiento (OR ajustado = 1.77; IC95% = 1.06-2.96; p = 0.028). Las calcificaciones vasculares cuantificadas a partir del score de Adragao fueron el único predictor independiente de mortalidad cardiovascular a largo plazo. Este score representa una herramienta simple, útil y superior a los biomarcadores del MOM.


Assuntos
Falência Renal Crônica , Calcificação Vascular , Biomarcadores , Fator de Crescimento de Fibroblastos 23 , Seguimentos , Humanos , Minerais , Estudos Prospectivos , Diálise Renal , alfa-2-Glicoproteína-HS
4.
J Evol Biol ; 33(9): 1294-1305, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32614995

RESUMO

Males of many species evolved the capability of adjusting their ejaculate phenotype in response to social cues to match the expected mating conditions. When females store sperm for a prolonged time, the expected fitness return of plastic adjustments of ejaculate phenotype may depend on the interval between mating and fertilization. Although prolonged female sperm storage (FSS) increases the opportunity for sperm competition, as a consequence of the longer temporal overlap of ejaculates from several males, it may also create variable selective forces on ejaculate phenotype, for example by exposing trade-offs between sperm velocity and sperm survival. We evaluated the relationship between the plasticity of ejaculate quality and FSS in the guppy, Poecilia reticulata, a polyandrous live-bearing fish in which females store sperm for several months and where stored sperm contribute significantly to a male's lifelong reproductive success. In this species, males respond to the perception of future mating opportunities by increasing the quantity (number) and quality (swimming velocity) of ready-to-use sperm (an anticipatory response called 'sperm priming'). Here we investigated (a) the effect of sperm priming on in vitro sperm viability at stripping and its temporal decline (as an estimate of sperm survival), and (b) the in vivo competitive fertilization success in relation to female sperm storage using artificial insemination. As expected, sperm-primed males produced more numerous and faster sperm, but with a reduced in vitro sperm viability at stripping and after 4 hr, compared with their counterparts. Artificial insemination revealed that the small (nonsignificant) advantage of primed sperm when fertilization immediately follows insemination is reversed when eggs are fertilized by female-stored sperm, weeks after insemination. By suggesting a plastic trade-off between sperm velocity and viability, these results demonstrate that prolonged female sperm storage generates divergent selection pressures on ejaculate phenotype.


Assuntos
Poecilia/fisiologia , Espermatozoides/fisiologia , Animais , Copulação , Feminino , Fertilização , Genitália Masculina/fisiologia , Masculino
5.
BMC Evol Biol ; 18(1): 186, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30526474

RESUMO

BACKGROUND: Comparing sexual size dimorphism (SSD) in the light of the phylogenetic hypothesis may help to understand the phenotypic evolution associated with sexual selection (size of whole body and of reproduction-related body parts). Within a macroevolutionary framework, we evaluated the association between the evolution of SSD and the evolution of reproduction-related phenotypic traits, and whether this association has favored female fecundity, considering also variations according to reproductive modes. We focused on the lizard species that inhabit the Chaco Domain since this is a natural unit with a high diversity of species. RESULTS: The residual SSD was related positively with the residuals of the reproduction-related phenotypic traits that estimate intrasexual selection and with the residuals of inter-limb length and, according to fecundity selection, those residuals were related positively with the residuals of clutch size in oviparous species. Lizards of the Chaco Domain present a high diversity of SSD patterns, probably related to the evolution of reproductive strategies. CONCLUSIONS: Our findings highlight that the sexual selection may have acted on the whole-body size as well as on the size of body parts related to reproduction. Male and female phenotypes evolutionarily respond to variations in SSD, and an understanding of these patterns is essential for elucidating the processes shaping sexual phenotype diversity from a macroevolutionary perspective.


Assuntos
Evolução Biológica , Tamanho Corporal , Lagartos/anatomia & histologia , Caracteres Sexuais , Animais , Brasil , Tamanho da Ninhada , Feminino , Fertilidade , Masculino , Fenótipo , Filogenia , Reprodução
6.
Biol Lett ; 14(5)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29848779

RESUMO

Male and female gametes are often embedded in fluids that are produced by gonads and other reproductive tissues. Female reproductive fluids, usually called ovarian fluid (OF), which often constitute a relevant volumetric component of the egg mass, are rich in ions, sugars and proteins, and are involved in several functions, from protecting gametes to facilitating fertilization, and often act as mediators of post-mating sexual selection. Despite their applied and evolutionary importance, we know virtually nothing about the costs of female reproductive fluid production. We investigated the effect of nutritional condition on OF quality by experimentally manipulating the diet of two groups of female guppies (Poecilia reticulata) which were maintained for 20 days either on a restricted diet or had ad libitum access to food. In this species, OF enhances sperm swimming longevity and velocity (a predictor of sperm competition success) and mediates post-copulatory inbreeding avoidance. We found that sperm velocity was significantly lower in the OF of diet-restricted females, indicating that OF quality is dependent on female nutritional condition. Our results demonstrate that OF represents a non-trivial component of female reproductive investment and provides a tool to investigate which OF constituents are involved in modulating OF-sperm interactions and fertilization.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Ovário/fisiologia , Poecilia/fisiologia , Motilidade dos Espermatozoides/fisiologia , Animais , Líquidos Corporais/fisiologia , Dieta/veterinária , Feminino , Endogamia , Masculino , Preferência de Acasalamento Animal , Estado Nutricional/fisiologia
7.
Theriogenology ; 118: 40-45, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29883843

RESUMO

The development of safe and consistent semen collection protocols should be ensured to understand basic sperm parameters of a species. Electroejaculation has been hypothesized and tested to be a safe method to evaluate male reproductive potential in wild animals. However, little is known about semen collection protocols in lizards. Adjusting stimulation to species and body mass is important for efficient semen collection as well as for animal welfare. Tropidurus spinulosus is a good model to adapt electrostimulation; it is a medium-sized lizard species, males have semen during a long period and operative sex ratio is male-biased. We aimed to provide a thorough and safe method for collecting semen samples from this animal model by means of electrostimulation and characterize basic sperm parameters. Mature males of T. spinulosus were captured and their testicular volume was evaluated via portable ultrasound scanning. The lizards were electrostimulated by performing standardized series of stimuli. Semen was obtained successfully in 94% of the males. Samples were contamination-free. Mean sperm number of ejaculates was 2.1 ±â€¯1.8 × 106 spermatozoids. The percentage of motile spermatozoa was 78% and sperm dynamic parameters were: VSL 37.26 ±â€¯7.72 µ/s and VCL 84.26 ±â€¯16.27 µ/s. We observed high variability in testicular volume among males; however, almost all the individuals had sperm. Electrostimulation using protocols adjusted to a medium-sized lizard was an effective semen collection method that allowed us to obtain semen samples with high motility (percentage of motile spermatozoa and sperm velocity).


Assuntos
Estimulação Elétrica , Lagartos , Sêmen , Coleta de Tecidos e Órgãos/veterinária , Animais , Ejaculação , Estimulação Elétrica/efeitos adversos , Masculino , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Testículo/anatomia & histologia , Testículo/diagnóstico por imagem , Coleta de Tecidos e Órgãos/métodos , Ultrassonografia/veterinária
8.
J Therm Biol ; 71: 202-208, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29301691

RESUMO

Reproduction is an energetically costly activity that can alter thermal requirements in Squamata. This phenomenon has been largely studied in many viviparous species; however, little is known about the role of oviparous females in controlling temperature during vitellogenesis and embryo development before oviposition. Diversity of female phenotypes could be associated with diversity of thermoregulatory performance, since thermal requirements are frequently influenced by body shape. Furthermore, studying the thermoregulatory behaviour is fundamental to understand how females regulate their body temperature. Here, we aimed to determine whether reproduction alters thermal requirements in an oviparous model, Tropidurus spinulosus, and if the preferred body temperature and thermoregulatory behaviour vary among reproductive stages and in relation to the female phenotype. We characterized the female phenotypes according to multiple morphological traits (snout-vent length, inter-axillar length, abdominal perimeter, body condition and head width). Reproductive structures were diagnosed by portable ultrasound scanning. To determine body temperatures, the lizards were placed in an open-top terrarium, where a thermal gradient ranging from 18 to 50°C was set up; we also recorded the permanence of individuals in cold, temperate and warm zones during each experiment. Reproductive females preferred higher temperatures and presented lower amplitude in thermal variability than non-reproductive females. Moreover, within reproductive females, females with wide abdominal perimeter and high body condition showed thermal stability. Females with oviductal eggs tended to select higher temperature and also show more thermal stability than females with vitellogenic follicles. The latter females used the temperate zone most frequently and to a lesser degree the warm one, whereas females with oviductal eggs used the temperate and warm zones with similarly high frequency. We conclude that reproductive stage and phenotypic traits influence the selection of preferred body temperatures and thermoregulatory behaviour in T. spinulosus females.


Assuntos
Temperatura Corporal , Lagartos/fisiologia , Oviparidade , Fenótipo , Reprodução , Aclimatação , Animais , Feminino , Masculino , Fatores Sexuais
9.
Scientifica (Cairo) ; 2016: 8176267, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110428

RESUMO

The reproductive traits of males are under influence of sexual pressures before and after copulation. The strength of sexual selection varies across populations because they undergo varying competition for mating opportunities. Besides intraspecific pressures, individuals seem to be subjected to pressures driven by interspecific interactions in sympatry. Lizards may vary their reproductive strategies through varying sexual characters, body size, gonadal investment, and sperm traits. We evaluated the reproductive traits, involved in pre- and postcopulatory competition, in allopatric and sympatric populations of Salvator lizards. We observed a spatial gradient of male competition among populations, with the following order: allopatric zone of S. rufescens; sympatric zone; and allopatric zone of S. merianae. Accordingly, variation in secondary sexual character, the relative testis mass, and the length of sperm component was observed between allopatry and sympatry in each species, suggesting differences in the investment of reproductive traits. However, we found that these two Salvator species did not differ in secondary sexual characters in sympatry. Interestingly, the trade-off between testes and muscle varied differently from allopatry to sympatry between these Salvator species, suggesting that the influence of social context on reproductive traits investment would affect lizard species differently.

10.
Rev. Nac. (Itauguá) ; 6(2): 63-68, dic 2014.
Artigo em Espanhol | LILACS | ID: biblio-884824

RESUMO

RESUMEN Se reporta cuatro casos: tres con dermatomiositis y uno con poliomiositis con compromiso pulmonar, tratados con pulsos de metilprednisolona asociado con azatioprina en tres casos y uno con ciclofosfamida, tres de ellos fallecieron, dos por complicaciones infecciosas pulmonares, el tercero por insuficiencia respiratoria aguda, Uno solo presento buena evolución bajo tratamiento con inmunoglobulina .En los cuatro pacientes el anticuerpo anti Jo fueron negativos.


ABSTRACT We report four cases, three with dermatomyositis and polymyositis one with pulmonary involvement treated with pulse methylprednisolone associated with azathioprine in three cases and one cyclophosphamide, three of them died, two infectious pulmonary complications, the third for acute respiratory failure, one presented good performance under treatment with immunoglobulin .In the four patients were negative anti Jo

11.
Int J Nephrol ; 2011: 246734, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21716690

RESUMO

We evaluated the efficacy of percutaneous ethanol injection therapy (PEIT) as a therapeutic option for recurrence of secondary hyperparathyroidism after subtotal parathyroidectomy in ESRD patients. Six patients underwent PEIT. A mean of 1.3 ± 0.8 ethanol injections was performed. Nodular volume was 1.5 ± 1.7 cm(3), and 2.8 ± 2.8 cm(3) of ethanol was injected per patient. After ethanol injection PTH decreased significantly (1897 ± 754 to 549 ± 863 pg/mL (P < .01)). There was also a reduction in serum calcium, phosphorus and calcium-phosphorus product. A positive and significant correlation was found between nodular volume with ethanol injected and time from parathyroidectomy. Only one patient required hospitalization due to severe hypocalcaemia. In other two cases, local discomfort and temporary mild dysphonia were registered. PEIT is an effective treatment to control recurrences of secondary hyperparathyroidism postsubtotal parathyroidectomy.

12.
Transpl Int ; 20(12): 1031-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17883371

RESUMO

Persistent hyperparathyroidism is frequent in postrenal transplant patients. Percutaneous ethanol injection therapy (PEIT) is an alternative for treatment of patients with secondary hyperparathyroidism but it was not described in postrenal transplant patients. We report our experience with PEIT to control hyperparathyroidism in the post-transplant period. We performed PEIT under ultrasonographic guidance and local anesthesia in eight patients because of persistent secondary hyperparathyroidism after renal transplantation. Indications for PEIT were: high intact parathyroid hormone (iPTH) levels with hypercalcemia, hypophosphatemia, osteopenia and/or bone pain. All patients had at least one visible parathyroid nodule by ultrasonography. Biochemical assays were performed immediately before PEIT, between 1 and 7 days after last PEIT, and a mean of 8.0 +/- 2.8 months after PEIT. Serum iPTH and calcium levels decreased significantly after treatment and remained unchanged until final control. Serum iPTH decreased from 286.9 +/- 107.2 to 154.6 +/- 42.2 pg/ml (P < 0.01) after PEIT (percentual reduction 36.5 +/- 9.5%). This response was significantly correlated to total ethanol volume used (r: 0.94, P < 0.0001). Hypercalcemia disappeared in six of eight patients treated. Only minor complications were registered. There were no changes in renal function related to the treatment. Our findings show that PEIT is a useful and safe alternative for patients with persistent post-transplant secondary hyperparathyroidism.


Assuntos
Etanol/administração & dosagem , Hiperparatireoidismo Secundário/tratamento farmacológico , Transplante de Rim , Complicações Pós-Operatórias/tratamento farmacológico , Adulto , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade
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