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Anuran skin is a dynamic organ involved in essential functions that strongly correlate with specific morphological traits. Particularly, gas exchange has been associated with epidermal modifications, such as reduced cell layers and increased vascularization. Here, we describe the epidermal morphology and its association with capillary networks in the dorsal skin of 103 Neotropical anurans (Nobleobatrachia) from different ecomorphs and habitats. Additionally, we examined the lateral and ventral skin for a subset of these species. We report intraepidermal capillaries in (i) dorsal skin of Lepidobatrachus laevis and Lepidobatrachus llanensis (burrowing and semi-aquatic Chacoan species), Hyloscirtus colymba and Hyloscirtus palmeri (arboreal species from humid forests), and Alsodes neuquensis and 15 Telmatobius spp. (aquatic and semi-aquatic species from cold environments); (ii) lateral skin of Boana benitezi and H. colymba (arboreal species from humid forests), and (iii) ventral skin of B. benitezi, H. colymba, Atelognathus patagonicus (aquatic species from cold environments), and four Chacoan species, Chacophrys pierottii, Ceratophrys cranwelli (burrowing/terrestrial species), and Lepidobatrachus asper and L. llanensis (burrowing/semi-aquatic species). Also, verrucae hydrophilicae were observed exclusively in the ventral skin of Leptodactylus fuscus, Leptodactylus laticeps (terrestrial and Chacoan species), and B. benitezi. Regardless of the skin region, the capillaries always penetrate the epidermis from the dermis, while epidermal cell layers are flattened. Our findings support previous hypotheses stating that the environment where species occur influences skin changes related to cutaneous respiration (intraepidermal capillaries in different body regions) and water absorption (intraepidermal capillaries associated with verrucae hydrophilicae within ventral skin). Also, phylogeny might influence the development of these structures, as revealed by the presence of intraepidermal capillaries in almost all analyzed species of Telmatobius. Finally, the co-occurrence of verrucae hydrophilicae in the ventral skin of hylids from humid forests, and leptodactylids from the subhumid Chacoan region suggest an independent origin., (© 2023 Wiley Periodicals LLC.)

The genus Pleurodema comprises 15 species distributed through the Neotropical region, from sea level up to 5000 m.a.s.l. A total-evidence analysis of Pleurodema is provided based on the parsimony criterion. The combined dataset included morphometric, phenotypic, and DNA evidence (34 taxa, 4441 characters). The parsimony analysis yielded one most-parsimonious tree. Pleurodema was recovered as a well-supported clade composed of two major subclades. One subclade has an identical topology to that of previous analyses, the P. brachyops Clade (P. alium, P. borellii, P. brachyops, P. cinereum, P. diplolister, and P. tucumanum). The other subclade includes the remaining nine species of the genus, exhibiting a topology different from that of previous studies. According to the present phylogeny, this second lineage is formed by the P. nebulosum Clade (P. guayapae + P. nebulosum), P. marmoratum, the re-defined P. thaul Clade (P. bufoninum, P. somuncurense, P. thaul) and the P. bibroni Clade (P. bibroni, P. cordobae, P. kriegi). The reproductive modes of Pleurodema represent a unique combination of features within Leiuperinae, including three egg-clutch structures, two types of amplexus, and lack of vocalization. Also, some species of Pleurodema have been considered fossorial, because they are capable of digging with their hind-limbs and remaining in self-made burrows during dry seasons. The evolution of characters associated with reproductive biology and fossoriality is discussed in light of the obtained results., (© 2022 Willi Hennig Society.)

This study describes the spermatozoa of 10 of the 15 species of the Neotropical frog genus Pleurodema through transmission electron microscopy. The diversity of oviposition modes coupled with a recent phylogenetic hypothesis of Pleurodema makes it an interesting group for the study of ultrastructural sperm evolution in relation to fertilization environment and egg-clutch structure. We found that Pleurodema has an unusual variability in sperm morphology. The more variable structures were the acrosomal complex, the midpiece, and the tail. The acrosomal complex has all the structures commonly reported in hyloid frogs but with different degree of development of the subacrosomal cone. Regarding the midpiece, the variability is given by the presence or absence of the mitochondrial collar. Finally, the tail is the most variable structure, ranging from single (only axoneme) to more complex (presence of paraxonemal rod, cytoplasmic sheath, and undulating membrane), with the absence of the typical axial fiber present in hyloid frogs, also shared with some other genera of Leiuperinae. J. Morphol. 277:957-977, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Rana lutea is one of the two anuran species described in 1782 by the Chilean born priest and naturalist Juan Ignacio Molina, and its nomenclatural history is confusing. After a detailed revision of the pertinent literature, we demonstrate that Bufo thaul Schneider, 1799, is a junior objective synonym of Rana lutea Molina, 1782, but based on the usage of both nomina, we revert the precedence and consider Rana lutea Molina, 1782 as a nomen oblitum whereas Bufo thaul Schneider, 1799 is a nomen protectum. Thus, the authorship of the species currently known as Pleurodema thaul (Lesson, 1826) changes to Pleurodema thaul (Schneider, 1799).

Species of the genus Pleurodema are relatively small, plump frogs that mostly occur in strong-seasonal and dry environments. The genus currently comprises 14 species distributed from Panama to southern Patagonia. Here we present a phylogenetic analysis of Pleurodema, including all described species and several outgroups. Our goals include testing its monophyly and the monophyly of the species groups that were historically proposed, and studying the evolution of some character systems, particularly macroglands and egg-clutch structure; this last point also provided the chance for a discussion of foam nest evolution in anurans. Our dataset includes portions of the mitochondrial genes cytochromeb, 12S, 16S, and the intervening tRNA Val ; the nuclear gene sequences include portions of rhodopsin exon 1 and seven in absentia homolog I. Our results support a clade composed of Pleurodema and including the monotypic SomuncuriaLynch, 1978 nested within it. The latter genus is therefore considered a junior synonym of Pleurodema and its sole species is added to this genus. Furthermore, our results indicate the non-monophyly of several species groups proposed previously. We recognize four clades in Pleurodema: the P. bibroni clade (P. bibroni, P. cordobae and P. kriegi), the P. thaul clade (P. bufoninum, P. marmoratum, P. somuncurensis and P. thaul), the P. brachyops clade (P. alium, P. borellii, P. brachyops, P. cinereum, P. diplolister and P. tucumanum) and the P. nebulosum clade (P. guayapae and P. nebulosum). Our results further indicate the need for a taxonomic reassessment of P. borellii and P. cinereum (as did previous studies), P. guayapae and P. nebulosum, and the three species in the P. bibroni clade. Pleurodema shows a striking pattern of variation in presence/absence of lumbar glands. Our results indicate multiple losses or independent gains of this character associated with defensive displays. The reproductive modes of Pleurodema include four different egg-clutch structures. The optimization of these indicates that there are at least two independent transformations from the plesiomorphic mode of foam nests to egg-clutch structures involving gelatinous masses of different sorts (ovoid plates, masses, or strings). We hypothesize that these independent transformations could involve changes at the behavioural (the loss of foam beating behaviour by the parent) and/or structural level (transformations involving the pars convoluta dilata, the section of the oviduct where the foam-making substance is secreted). Finally, our study of foam nest evolution in Pleurodema is extended to the other groups of anurans where foam-nesting occurs, on the basis of available data and recent phylogenetic hypotheses. In the different hyloid groups where it occurs, foam-nesting evolved from clutches laid in water. However, in all ranoids in which foam-nesting occurs, it evolved from terrestrial clutches, with eggs laid hanging in vegetation, or, if the clutches are laid on a restricted volume of water, involving endotrophic development. © The Willi Hennig Society 2012., (© The Willi Hennig Society 2012.)

Background: Perinatal psychiatric disturbances afflict a significant number of women sometimes with tragic consequence. Yet, the range and characteristics of these disturbances are poorly understood. The goals of this research were to characterize a broader range of postpartum psychiatric symptoms and to identify their inherent structure using exploratory factor analysis (EFA)., Methods: An Internet-based survey with 142 Likert-type questions, covering nine dimensions of postpartum mental health was constructed and posted on women's health websites. Data collected from 215 respondents was analyzed in three steps: (1) inter-item correlations were used to reduce the total number of variables by eliminating items that provided redundant information; (2) an EFA using a principal components extraction and VARIMAX rotation was performed and factors loading with Eigenvalues >1.0 were retained; (3) internal consistency was measured with Cronbach's alpha., Results: The 10 factors retained accounted for 58% of the variance and included: mental status (28%), psychoticism/morbid thoughts (6%), generalized anxiety (6%), panic (3%), guilt/self-criticism (3%), compulsive behavior (3%), hyper-vigilance (2%), contentment (2%), negative body-image (2%), and manic behavior (2%). There was strong (>0.8) internal consistency in all but the mania factor (0.6)., Limitations: The study was retrospective and respondent demographics were homogeneous., Conclusion: Postpartum psychiatric disturbances are not limited to depressive symptoms. In the current study, cognitive difficulties, psychotic-morbid thoughts and anxiety symptoms accounted for the preponderance of variance while depressive symptoms did not form a cohesive factor and accounted for minimal variance. These results suggest postpartum screening tools should assess a broader array of symptoms.

The cannabinoids produce a variety of effects on unlearned behavior in different animal species. The voluminous literature pertaining to cannabis and unlearned behavior has been reviewed in the five previous Marihuana and Health Reports (1971 through 1975). The present chapter relies heavily on these previous reports for background and focuses primarily on the relevant literature which has appeared during the past two years, although a continuing attempt is made to consider the more recent literature in the context of previous findings. As in the 1975 Marihuana and Health Report, the present chapter is organized for expository purposes around four categories of unlearned behavior: gross behavior; activity and exploration; consummatory behavior; and aggressive behavior.

Although covert sensitization is a widely and diversely employed clinical technique, there is no generally accepted conceptual guideline for its implementation. Consequently, there is considerable variability in the way covert sensitization procedures are employed, which may account for the reported inconsistency in its clinical effectiveness. The present study is an analogue experimental test of a conceptual account of covert sensitization that is based upon classical conditioning. The classical conditioning procedure is viewed as affecting operant target behaviors by altering the reinforcer effectiveness of target stimuli. This was explicitly tested by examining the effects of covert sensitization on subjects' preference for sexual stimuli in an operant choice paradigm. The results support the conceptual account.

Two Macaca mulatta and one macaca java monkey were trained to press a key for food pellets on a differential reinforcement of low rate (DRL) schedule which required consecutive key-press responses to be spaced at least 20 sec apart in order to produce reinforcement. When behavior had stabilized, the monkeys were administered either 0.0,0.05,0.10,0.25, or 0.50 mg/kg of cocaine i.v. during daily sessions. Cocaine produced a bi-component, dose-dependent effect. Immediately following cocaine infusion there was a dose-related complete cessation of responding which began and ended abruptly. Following this postinfusion pause, a dose-related behavioral disruption in the form of shortened inter-response times was observed.

A review of the previous Marihuana and Health Reports (1971-1975) reveals that an extensive array of experimental procedures and contexts have been used to study the effects of cannabinoids on the performance of learned behavior in animals. These preclinical behavioral experiments have provided a framework for, and guided the design of, subsequent human experimentation. Compared to previous years, only a few experiments pertaining to cannabinoids and learned behavior have appeared during the past two years. By and large these more recent experiments confirm previous findings; no particularly novel procedures have been explored nor have there been dramatically unpredictable results. In part, the decrease in activity in cannabinoid preclinical animal research on learned behavior indicates an increase in human cannabinoid-learning investigations. Several detailed taxonomies of learned behavior are possible. However, for the purposes of the present report, learned behaviors will be categorized into those involving: avoidance learning and aversive control; reinforcement schedules and maze learning; and discrimination learning.

Sequential IRT data were obtained for three rats on a DRL 60-sec reinforcement schedule. It was found that first-order sequential dependencies exist under this schedule, including the partial dependence of the length of any given IRT on the length of the preceding IRT. The sequential analysis also served to extend the finding in the literature, based on frequency distributions, that the likelihood of a reinforced IRT is greater after a reinforced IRT than a non-reinforced IRT. Rapid extinction and reconditioning were obtained.

Five chimpanzees were given Delta(9)-tetrahydrocannabinol (Delta(9)THC): 1.0 milligram per kilogram of body weight for 21 days and 4.0 milligrams per kilogram of body weight for 42 days. Although accuracy and speed of performance on a delayed matching-to-sample task were significantly affected by both doses, tolerance to Delta(9)THC did not develop. No long-term behavioral effects of Delta(9)THC were observed after termination of the drug regimens.