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1.
Pesqui. vet. bras ; 39(12): 997-1004, Dec. 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-26431

RESUMO

The nurse shark, Ginglymostoma cirratum (Bonnaterre, 1778) is one of the most studied species of elasmobranchs. However, the knowledge of their reproductive biology is still relatively rare, particularly in the western South Atlantic. This study aimed to describe the morphology of the uterus and the ovary of G. cirratum, based on specimens caught off at the Fortaleza/CE coast, northeast Brazil. Samples were collected from September 2012 to June 2013, from regular landings of artisanal fishing, which commercialize this species freely. A total of ten females were collected. The methodologies followed for analyzing the ovaries and uterus of those females included both macroscopic and histological analysis. G. cirratum has internal type ovary morphology, with invaginations of connective tissue, which defines compartments and separate oocyte groups in ovigerous lots. The epithelium lining the ovary changes from simple columnar ciliated in the area without ovigerous lots, which turns into a simple cubic epithelium in the coating portion of the epigonal organ where ovarian tissue is absent. The uterine mucosa has secretory cells denoted by Alcian Blue staining, indicating the production of mucopolysaccharides, even in immature individuals. This lecithotrophic shark has a uterine vascularized mucosa that is one characteristic of viviparous elasmobranch species.(AU)


O tubarão-lixa, Ginglymostoma cirratum (Bonnaterre, 1778) é uma das espécies mais estudadas de elasmobrânquios. O conhecimento de sua biologia reprodutiva, no entanto, ainda é relativamente raro, particularmente no Oeste do Atlântico Sul. Este estudo objetivou a descrição morfológica do útero e ovário de G. cirratum, baseado em espécimes capturados na costa de Fortaleza/CE, no Nordeste do Brasil. Um total de dez fêmeas foi coletado de setembro de 2012 a junho de 2013, nos desembarques regulares da pesca artesanal, que comercializam essa espécie livremente. A metodologia foi de acordo com as analises macroscópica e histológica dos ovários e útero. G. cirratum tem o tipo de morfologia de ovário interno, com invaginações de tecido conjuntivo, que define compartimentos e separa grupos de oócitos em lotes ovígeros. O epitélio que reveste o ovário varia de epitélio simples colunar ciliado na área que não apresenta lotes ovígeros para epitélio simples cúbico na porção de revestimento do órgão epigonal, onde o tecido ovariano é ausente. A mucosa uterina possui células secretoras, evidenciadas pela coloração em Alcian Blue, indicando a produção de mucopolissacarídeos, mesmo em indivíduos imaturos. Este tubarão lecitotrófico apresenta a mucosa uterina vascularizada, sendo esta uma característica de espécies de elasmobrânquios vivíparos.(AU)


Assuntos
Animais , Feminino , Ovário/anatomia & histologia , Tubarões/anatomia & histologia , Útero/anatomia & histologia
2.
Pesqui. vet. bras ; Pesqui. vet. bras;39(12): 997-1004, Dec. 2019. ilus
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1056922

RESUMO

The nurse shark, Ginglymostoma cirratum (Bonnaterre, 1778) is one of the most studied species of elasmobranchs. However, the knowledge of their reproductive biology is still relatively rare, particularly in the western South Atlantic. This study aimed to describe the morphology of the uterus and the ovary of G. cirratum, based on specimens caught off at the Fortaleza/CE coast, northeast Brazil. Samples were collected from September 2012 to June 2013, from regular landings of artisanal fishing, which commercialize this species freely. A total of ten females were collected. The methodologies followed for analyzing the ovaries and uterus of those females included both macroscopic and histological analysis. G. cirratum has internal type ovary morphology, with invaginations of connective tissue, which defines compartments and separate oocyte groups in ovigerous lots. The epithelium lining the ovary changes from simple columnar ciliated in the area without ovigerous lots, which turns into a simple cubic epithelium in the coating portion of the epigonal organ where ovarian tissue is absent. The uterine mucosa has secretory cells denoted by Alcian Blue staining, indicating the production of mucopolysaccharides, even in immature individuals. This lecithotrophic shark has a uterine vascularized mucosa that is one characteristic of viviparous elasmobranch species.(AU)


O tubarão-lixa, Ginglymostoma cirratum (Bonnaterre, 1778) é uma das espécies mais estudadas de elasmobrânquios. O conhecimento de sua biologia reprodutiva, no entanto, ainda é relativamente raro, particularmente no Oeste do Atlântico Sul. Este estudo objetivou a descrição morfológica do útero e ovário de G. cirratum, baseado em espécimes capturados na costa de Fortaleza/CE, no Nordeste do Brasil. Um total de dez fêmeas foi coletado de setembro de 2012 a junho de 2013, nos desembarques regulares da pesca artesanal, que comercializam essa espécie livremente. A metodologia foi de acordo com as analises macroscópica e histológica dos ovários e útero. G. cirratum tem o tipo de morfologia de ovário interno, com invaginações de tecido conjuntivo, que define compartimentos e separa grupos de oócitos em lotes ovígeros. O epitélio que reveste o ovário varia de epitélio simples colunar ciliado na área que não apresenta lotes ovígeros para epitélio simples cúbico na porção de revestimento do órgão epigonal, onde o tecido ovariano é ausente. A mucosa uterina possui células secretoras, evidenciadas pela coloração em Alcian Blue, indicando a produção de mucopolissacarídeos, mesmo em indivíduos imaturos. Este tubarão lecitotrófico apresenta a mucosa uterina vascularizada, sendo esta uma característica de espécies de elasmobrânquios vivíparos.(AU)


Assuntos
Animais , Feminino , Ovário/anatomia & histologia , Tubarões/anatomia & histologia , Útero/anatomia & histologia
3.
Pesqui. vet. bras ; 39(12)2019.
Artigo em Inglês | VETINDEX | ID: vti-745804

RESUMO

ABSTRACT: The nurse shark, Ginglymostoma cirratum (Bonnaterre, 1778) is one of the most studied species of elasmobranchs. However, the knowledge of their reproductive biology is still relatively rare, particularly in the western South Atlantic. This study aimed to describe the morphology of the uterus and the ovary of G. cirratum, based on specimens caught off at the Fortaleza/CE coast, northeast Brazil. Samples were collected from September 2012 to June 2013, from regular landings of artisanal fishing, which commercialize this species freely. A total of ten females were collected. The methodologies followed for analyzing the ovaries and uterus of those females included both macroscopic and histological analysis. G. cirratum has internal type ovary morphology, with invaginations of connective tissue, which defines compartments and separate oocyte groups in ovigerous lots. The epithelium lining the ovary changes from simple columnar ciliated in the area without ovigerous lots, which turns into a simple cubic epithelium in the coating portion of the epigonal organ where ovarian tissue is absent. The uterine mucosa has secretory cells denoted by Alcian Blue staining, indicating the production of mucopolysaccharides, even in immature individuals. This lecithotrophic shark has a uterine vascularized mucosa that is one characteristic of viviparous elasmobranch species.


RESUMO: O tubarão-lixa, Ginglymostoma cirratum (Bonnaterre, 1778) é uma das espécies mais estudadas de elasmobrânquios. O conhecimento de sua biologia reprodutiva, no entanto, ainda é relativamente raro, particularmente no Oeste do Atlântico Sul. Este estudo objetivou a descrição morfológica do útero e ovário de G. cirratum, baseado em espécimes capturados na costa de Fortaleza/CE, no Nordeste do Brasil. Um total de dez fêmeas foi coletado de setembro de 2012 a junho de 2013, nos desembarques regulares da pesca artesanal, que comercializam essa espécie livremente. A metodologia foi de acordo com as analises macroscópica e histológica dos ovários e útero. G. cirratum tem o tipo de morfologia de ovário interno, com invaginações de tecido conjuntivo, que define compartimentos e separa grupos de oócitos em lotes ovígeros. O epitélio que reveste o ovário varia de epitélio simples colunar ciliado na área que não apresenta lotes ovígeros para epitélio simples cúbico na porção de revestimento do órgão epigonal, onde o tecido ovariano é ausente. A mucosa uterina possui células secretoras, evidenciadas pela coloração em Alcian Blue, indicando a produção de mucopolissacarídeos, mesmo em indivíduos imaturos. Este tubarão lecitotrófico apresenta a mucosa uterina vascularizada, sendo esta uma característica de espécies de elasmobrânquios vivíparos.

4.
Proc Natl Acad Sci U S A ; 115(47): 11982-11987, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30373825

RESUMO

Montane species worldwide are shifting upslope in response to recent temperature increases. These upslope shifts are predicted to lead to mountaintop extinctions of species that live only near mountain summits, but empirical examples of populations that have disappeared are sparse. We show that recent warming constitutes an "escalator to extinction" for birds on a remote Peruvian mountain-high-elevation species have declined in both range size and abundance, and several previously common mountaintop residents have disappeared from the local community. Our findings support projections that warming will likely drive widespread extirpations and extinctions of high-elevation taxa in the tropical Andes. Such climate change-driven mountaintop extirpations may be more likely in the tropics, where temperature seems to exert a stronger control on species' range limits than in the temperate zone. In contrast, we show that lowland bird species at our study site are expanding in range size as they shift their upper limits upslope and may thus benefit from climate change.


Assuntos
Distribuição Animal/fisiologia , Aves/fisiologia , Dinâmica Populacional/tendências , Altitude , Migração Animal/fisiologia , Animais , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Extinção Biológica , Previsões , Comportamento de Retorno ao Território Vital , Peru , Temperatura , Clima Tropical
6.
Mol Ecol ; 26(18): 4631-4643, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28734054

RESUMO

Heterozygosity-fitness correlations (HFCs) have been examined in a wide diversity of contexts, and the results are often used to infer the role of inbreeding in natural populations. Although population demography, reflected in population-level genetic parameters such as allelic diversity or identity disequilibrium, is expected to play a role in the emergence and detectability of HFCs, direct comparisons of variation in HFCs across many populations of the same species, with different genetic histories, are rare. Here, we examined the relationship between individual microsatellite heterozygosity and a range of sexually selected traits in 660 male guppies from 22 natural populations in Trinidad. Similar to previous studies, observed HFCs were weak overall. However, variation in HFCs among populations was high for some traits (although these variances were not statistically different from zero). Population-level genetic parameters, specifically genetic diversity levels (number of alleles, observed/expected heterozygosity) and measures of identity disequilibrium (g2 and heterozygosity-heterozygosity correlations), were not associated with variation in population-level HFCs. This latter result indicates that these metrics do not necessarily provide a reliable predictor of HFC effect sizes across populations. Importantly, diversity and identity disequilibrium statistics were not correlated, providing empirical evidence that these metrics capture different essential characteristics of populations. A complex genetic architecture likely underpins multiple fitness traits, including those associated with male fitness, which may have reduced our ability to detect HFCs in guppy populations. Further advances in this field would benefit from additional research to determine the demographic contexts in which HFCs are most likely to occur.


Assuntos
Aptidão Genética , Genética Populacional , Heterozigoto , Poecilia/genética , Caracteres Sexuais , Animais , Variação Genética , Endogamia , Masculino , Repetições de Microssatélites , Seleção Genética , Trinidad e Tobago
7.
Int. braz. j. urol ; 43(3): 394-406, May.-June 2017. graf
Artigo em Inglês | LILACS | ID: biblio-840842

RESUMO

ABSTRACT Background Shock wave lithotripsy (SWL) is the first line treatment modality for a significant proportion of patients with upper urinary tracts stones. Simple analgesics, opioids and non-steroidal anti-inflammatory drugs (NSAIDs) are all suitable agents but the relative efficacy and tolerability of these agents is uncertain. Objectives To determine the efficacy of the different types of analgesics used for the control of pain during SWL for urinary stones. Materials and Methods We searched the Cochrane Renal Group’s Specialised Register, MEDLINE, EMBASE and also hand-searched reference lists of relevant articles (Figure-1). Randomised controlled trials (RCT’s) comparing the use of any opioid, simple analgesic or NSAID during SWL were included. These were compared with themselves, each-other or placebo. We included any route or form of administration (bolus, PCA). We excluded agents that were used for their sedative qualities. Data were extracted and assessed for quality independently by three reviewers. Meta-analyses have been performed where possible. When not possible, descriptive analyses of variables were performed. Dichotomous outcomes are reported as relative risk (RR) and measurements on continuous scales are reported as weighted mean differences (WMD) with 95% confidence intervals. Results Overall, we included 9 RCTs (539 participants from 6 countries). Trial agents included 7 types of NSAIDs, 1 simple analgesic and 4 types of opioids. There were no significant differences in clinical efficacy or tolerability between a simple analgesic (paracetamol) and an NSAID (lornoxicam). When comparing the same simple analgesic with an opioid (tramadol), both agents provided safe and effective analgesia for the purpose of SWL with no significant differences. There were no significant differences in pain scores between NSAIDs or opioids in three studies. Adequate analgesia could be achieved more often for opioids than for NSAIDs (RR 0.358; 95% CI 043 to 0.77, P=0.0002) but consumed doses of rescue analgesia were similar between NSAIDs and opioids in two studies (P=0.58, >0.05). In terms of tolerability, there is no difference in post-operative nausea and vomiting (PONV) between the groups (RR 0.72, 95% CI 0.24 to 2.17, P=0.55). One study compared outcomes between two types of NSAIDs (diclofenac versus dexketoprofen). There were no significant differences in any of our pre-defined outcomes measures. Conclusion Simple analgesics, NSAIDs and opioids can all reduce the pain associated with shock wave lithotripsy to a level where the procedure is tolerated. Whilst there are no compelling differences in safety or efficacy of simple analgesics and NSAIDs, analgesia is described as adequate more often for opioids than NSAIDs.


Assuntos
Humanos , Litotripsia/efeitos adversos , Cálculos Urinários/cirurgia , Analgesia/métodos , Analgésicos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Analgésicos/classificação
8.
Int Braz J Urol ; 43(3): 394-406, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28338301

RESUMO

BACKGROUND: Shock wave lithotripsy (SWL) is the first line treatment modality for a significant proportion of patients with upper urinary tracts stones. Simple analgesics, opioids and non-steroidal anti-inflammatory drugs (NSAIDs) are all suitable agents but the relative efficacy and tolerability of these agents is uncertain. OBJECTIVES: To determine the efficacy of the different types of analgesics used for the control of pain during SWL for urinary stones. MATERIALS AND METHODS: We searched the Cochrane Renal Group's Specialised Register, MEDLINE, EMBASE and also hand-searched reference lists of relevant articles (Figure-1). Randomised controlled trials (RCT's) comparing the use of any opioid, simple analgesic or NSAID during SWL were included. These were compared with themselves, each-other or placebo. We included any route or form of administration (bolus, PCA). We excluded agents that were used for their sedative qualities. Data were extracted and assessed for quality independently by three reviewers. Meta-analyses have been performed where possible. When not possible, descriptive analyses of variables were performed. Dichotomous outcomes are reported as relative risk (RR) and measurements on continuous scales are reported as weighted mean differences (WMD) with 95% confidence intervals. RESULTS: Overall, we included 9 RCTs (539 participants from 6 countries). Trial agents included 7 types of NSAIDs, 1 simple analgesic and 4 types of opioids. There were no significant differences in clinical efficacy or tolerability between a simple analgesic (paracetamol) and an NSAID (lornoxicam). When comparing the same simple analgesic with an opioid (tramadol), both agents provided safe and effective analgesia for the purpose of SWL with no significant differences. There were no significant differences in pain scores between NSAIDs or opioids in three studies. Adequate analgesia could be achieved more often for opioids than for NSAIDs (RR 0.358; 95% CI 043 to 0.77, P=0.0002) but consumed doses of rescue analgesia were similar between NSAIDs and opioids in two studies (P=0.58, >0.05). In terms of tolerability, there is no difference in post-operative nausea and vomiting (PONV) between the groups (RR 0.72, 95% CI 0.24 to 2.17, P=0.55). One study compared outcomes between two types of NSAIDs (diclofenac versus dexketoprofen). There were no significant differences in any of our pre-defined outcomes measures. CONCLUSION: Simple analgesics, NSAIDs and opioids can all reduce the pain associated with shock wave lithotripsy to a level where the procedure is tolerated. Whilst there are no compelling differences in safety or efficacy of simple analgesics and NSAIDs, analgesia is described as adequate more often for opioids than NSAIDs.


Assuntos
Analgesia/métodos , Analgésicos Opioides/administração & dosagem , Analgésicos/administração & dosagem , Litotripsia/efeitos adversos , Cálculos Urinários/cirurgia , Analgésicos/classificação , Humanos , Dor Pós-Operatória/tratamento farmacológico
9.
Anat Rec (Hoboken) ; 299(6): 759-68, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26864330

RESUMO

Characterization of the reproductive anatomy of elasmobranchs (sharks, skates, rays, and sawfish) offers unique insights into the evolution of reproductive traits in animals due to their phylogenetic position at the base of the vertebrate tree of life. Yet, despite advances in our understanding of male elasmobranch reproductive physiology and testes histology, very little is known about how testes histomorphometrics varies with male maturation. In this study, we characterize and contrast testes morphology and histomorphology of males at different maturation stages in three shark species with diametric testes development: Prionaceglauca, Rhizoprionodon lalandii, and Mustelus canis. All stages of spermatogenesis were observed in P. glauca and R. lalandii, while for M. canis, only males at early stages of maturation were examined and therefore all the spermatogenesis cells lineage were not present. The number of Sertoli cells increased with cell development by six times in R. lalandii and roughly four times in P. glauca, and were statistically different among stages of spermatogenesis cysts in both species. Statistical differences in cyst diameter and Sertoli cell numbers were observed between P. glauca and R. lalandii. The increase of spermatocyte II cell diameter described for R. Lalandii in this study was not usual to elasmobranch species as compared, for example, to P. glauca. This information proves the importance of studying the testicular development and the process of spermatogenesis is necessary for understanding the reproductive biology of the species, including life cycles and history, variation of reproductive morphology. Anat Rec, 299:759-768, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Células de Sertoli/citologia , Tubarões/anatomia & histologia , Espermatogênese/fisiologia , Espermatozoides/citologia , Testículo/anatomia & histologia , Animais , Masculino , Tubarões/fisiologia , Testículo/fisiologia
10.
PLoS One ; 8(3): e58519, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23472203

RESUMO

One of the most common visual adaptations seen in the mesopelagic zone (200-1000 m), where the amount of light diminishes exponentially with depth and where bioluminescent organisms predominate, is the enlargement of the eye and pupil area. However, it remains unclear how eye size is influenced by depth, other environmental conditions and phylogeny. In this study, we determine the factors influencing variability in eye size and assess whether this variability is explained by ecological differences in habitat and lifestyle within a family of mesopelagic fishes characterized by broad intra- and interspecific variance in depth range and luminous patterns. We focus our study on the lanternfish family (Myctophidae) and hypothesise that lanternfishes with a deeper distribution and/or a reduction of bioluminescent emissions have smaller eyes and that ecological factors rather than phylogenetic relationships will drive the evolution of the visual system. Eye diameter and standard length were measured in 237 individuals from 61 species of lanternfishes representing all the recognised tribes within the family in addition to compiling an ecological dataset including depth distribution during night and day and the location and sexual dimorphism of luminous organs. Hypotheses were tested by investigating the relationship between the relative size of the eye (corrected for body size) and variations in depth and/or patterns of luminous-organs using phylogenetic comparative analyses. Results show a great variability in relative eye size within the Myctophidae at all taxonomic levels (from subfamily to genus), suggesting that this character may have evolved several times. However, variability in eye size within the family could not be explained by any of our ecological variables (bioluminescence and depth patterns), and appears to be driven solely by phylogenetic relationships.


Assuntos
Olho/anatomia & histologia , Peixes/anatomia & histologia , Peixes/fisiologia , Animais , Austrália , Tamanho Corporal , Chile , Ecossistema , Luz , Modelos Lineares , Fenômenos Fisiológicos Oculares , Tamanho do Órgão , Peru , Filogenia , Especificidade da Espécie
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