Age and sex effects on histological features and in vitro culturing of Antillean manatee (Trichechus manatus manatus, Linnaeus 1758) dermis.

The biobanks from dermal biopsies represent an interesting strategy for biodiversity conservation. Nevertheless, the morphological and cellular patterns of the dermis can be influenced by the age and sex of the individual. Therefore, evaluating these factors is interesting for forming biobanks of Antillean manatees. These animals, representatives of marine fauna, have had their population reduced, and biobanks are essential for their conservation. Then, we evaluated the effects of age (3.5 years vs. 3.6-16 years vs. 23.6 years) and sex (males vs. females) on morphological and cellular parameters using histological and in vitro culture techniques. Regardless of age, no differences were observed for dermal thickness, collagen fibres, tissue proliferative activity and viable cell recovery. Nonetheless, fibroblast reduction was observed in groups aged 23.6 years compared to other animals (p < 0.05). Additionally, cells from animals aged 3.6-16 years showed more significant mitochondrial damage than the other groups (p < 0.05). Regardless of sex, no differences were observed for dermal thickness, collagen fibres, tissue proliferative activity and viable cell recovery; however, females had fewer fibroblasts than males (p < 0.05). Cells from females showed lower mitochondrial damage when compared to cells from males. In summary, although age and sex do not influence dermal thickness and cell recovery, variations in the number of fibroblasts and mitochondrial characteristics were observed among the groups. These differences may be significant for understanding the dermis aspects to be correlated to biobank systems.

The dermal armor of mylodontid sloths (Mammalia, Xenarthra) from Cueva del Milodón (Última Esperanza, Chile).

Dermal ossifications (osteoderms, dermal ossicles, osteoscutes) appear independently in various tetrapod lineages. In mammals, however, dermal ossifications are only present in some members of Xenarthra. This clade includes Cingulata (armadillos and their relatives), and Pilosa, including Vermilingua (anteaters) and Folivora (sloths). In extant xenarthrans, osteoderms are invariably present in cingulates whereas they are absent in pilosans. Among extinct sloths, however, a limited number of taxa possessed dermal ossifications. Records of mummified skins of ground sloths bearing osteoderms found in Cueva del Milodón (Southern Chile), with a late Pleistocene age, allowed us to analyze their micro- and macroscopic morphology. The main goal of this study is to closely examine a portion of a mylodontid skin portion using radiography. The arrangement, morphology and internal structure of the ossicles are analyzed and the results are discussed in the context of previous research. The results we obtained indicate that ossicles vary in shape and size, and the integument has four different patterns of arrangement of the ossicles: that is, areas without ossicles, disorganized ossicles, rows, and mosaic areas. The latter has two variants, with clusters of ossicles forming rosettes or stars. Thin sections of the ossicles allowed us to recognize and describe anatomical features of the bone and its mode of growth. Finally, paleobiological and functional considerations of the dermal armor are discussed along with its phylogenetic and chronological implications.

Relación entre el patrón dactiloscópico epidérmico y dérmico / Relationship between the epidermal and the dermal dactyloscopic pattern

El método más utilizado en identificación humana es el dactiloscópico, que registra, analiza y coteja los tipos fundamentales y puntos característicos de las figuras presentes en el dactilograma, determinando el grado de coincidencia, entre un patrón de identidad dubitada y uno de identidad indubitada. Debido a los procesos que afectan la piel de cadáveres, como la putrefacción entre otros, se utilizan las técnicas necropapiloscópicas que ocupan los patrones dérmicos para la identificación humana. El objetivo del presente trabajo es comparar registros epidérmicos con dérmicos, y validar científicamente, este método de identificación (epidérmico - dérmico). Para ello se utilizaron 32 dedos de cadáveres de individuos chilenos, de ambos sexos y de entre 40 y 80 años. Para obtener el registro físico artificial epidérmico y dérmico se utilizó la técnica de obtención de impresiones necrodactilares y se comparó a través de la técnica de cotejo dactiloscópico. Estos procedimientos fueron realizados por peritos criminalísticos de Carabineros de Chile. Se logró evidenciar diferencias importantes entre epidermis y dermis en cuanto a cantidad y calidad de puntos característicos y presencia de líneas seniles. En relación a tipos fundamentales, se evidenció que en dermis es difícil la observación de tipos fundamentales (borrosos) pero no se encontró ningún dígito que presentara tipo fundamental diferente entre epidermis y dermis. También se constataron diferencias por sexo y edad. Finalmente se pudo evidenciar, que existe una relación morfológica semejante entre registros físicos artificiales de patrones papiloscópicos epidérmicos con dérmicos provenientes del mismo individuo. Esto permite utilizar los registros dérmicos para la identificación humana positiva. Los resultados de este trabajo son importantes al aportar evidencia científica para la identificación humana en base al patrón dactiloscópico dérmico.

The most used method in human identification is the dactyloscopy, which registers, analyzes and collates the fundamental types and characteristic points of figures present in the dactylogram determining the degree of coincidence, between a pattern of identity that is dubious, and one that is indubious. Due to the processes that affect the skin of corpses, such as putrefaction, the necropapiloscopy techniques that occupy the dermal patterns for human identification are used. The objective of the present work is to compare epidermal with dermal records and validate scientifically, this method of identification (epidermal - dermal). For this purpose, 32 cadaveric fingers of Chilean individuals, of both sexes and between 40 and 80 years were used. In order to obtain the epidermal and dermal artificial physical record, the technique of obtaining necrodactyle impressions was used and compared through of the technique of dactyloscopic comparison. These procedures were carried out by criminalistic experts of Carabineros de Chile. It was possible to show important differences between epidermis and dermis in terms of quantity and quality of characteristic points and presence of senile lines. In relation to fundamental types, it was evidenced that in the dermis it is difficult to observe fundamental types (blurred) but no digit was found that presented a different of fundamental type between epidermis and dermis. There were also differences by sex and age. Finally, it was possible to demonstrate that there is a similar morphological relationship between artificial physical records of epidermal papiloscopic patterns with dermal patterns from the same individual. This allows the use of dermal records for positive human identification. The results of this work are important in providing scientific evidence for human identification based on the dermal fingerprint pattern.

Caloric Restriction Promotes Structural and Metabolic Changes in the Skin.

Caloric restriction (CR) is the most effective intervention known to enhance lifespan, but its effect on the skin is poorly understood. Here, we show that CR mice display fur coat remodeling associated with an expansion of the hair follicle stem cell (HFSC) pool. We also find that the dermal adipocyte depot (dWAT) is underdeveloped in CR animals. The dermal/vennule annulus vasculature is enlarged, and a vascular endothelial growth factor (VEGF) switch and metabolic reprogramming in both the dermis and the epidermis are observed. When the fur coat is removed, CR mice display increased energy expenditure associated with lean weight loss and locomotion impairment. Our findings indicate that CR promotes extensive skin and fur remodeling. These changes are necessary for thermal homeostasis and metabolic fitness under conditions of limited energy intake, suggesting a potential adaptive mechanism.

Dermal type I collagen assessment by digital image analysis.

Type I collagen is the main dermal component, and its evaluation is relevant to quantitative studies in dermatopathology. However, visual gradation (0 to 4+) has low precision and high subjectivity levels. This study aimed to develop and validate a digital morphometric analysis technique to estimate type I collagen levels in the papillary dermis. Four evaluators visually quantified (0 to 4+) the density of type I collagen in 63 images of forearm skin biopsies marked by immunohistochemistry and two evaluators analyzed the same images using digital morphometric techniques (RGB split colors (I) and color deconvolution (II)). Automated type I collagen density estimation in the papillary dermis (two techniques) were correlated with visual evaluations (Spearman's rho coefficients of 0.48 and 0.62 (p<0.01)). With regard to the inter-observer repeatability, the four evaluators who used visual classification had an intraclass correlation coefficient (for absolute agreement) of 0.53, while the other two evaluators who used digital analysis (algorithm II) had an intraclass correlation coefficient of 0.97.

Does osteoderm growth follow energy minimization principles?

Although the growth and development of tissues and organs of extinct species cannot be directly observed, their fossils can record and preserve evidence of these mechanisms. It is generally accepted that bone architecture is the result of genetically based biomechanical constraints, but what about osteoderms? In this article, the influence of physical constraints on cranial osteoderms growth is assessed. Comparisons among lepidosaurs, synapsids, and archosaurs are performed; according to these analyses, lepidosaur osteoderms growth is predicted to be less energy demanding than that of synapsids and archosaurs. Obtained results also show that, from an energetic viewpoint, ankylosaurid osteoderms growth resembles more that of mammals than the one of reptilians, adding evidence to debate whether dinosaurs were hot or cold blooded.

Morphological characters of the thickbody skate Amblyraja frerichsi (Krefft 1968) (Rajiformes: Rajidae), with notes on its biology.

Detailed descriptions of morphological features, morphometrics, neurocranium anatomy, clasper structure and egg case descriptions are provided for the thickbody skate Amblyraja frerichsi; a rare, deep-water species from Chile, Argentina and Falkland Islands. The species diagnosis is complemented from new observations and aspects such as colour, size and distribution are described. Geographic and bathymetric distributional ranges are discussed as relevant features of this taxons biology. Additionally, the conservation status is assessed including bycatch records from Chilean fisheries.

Manejo de lesiones vasculares benignas

Las lesiones vasculares benignas son básicamente hemangiomas y malformaciones vasculares. El diagnóstico preciso permite el tratamiento más adecuado a cada paciente. El conocimiento de las diferentes formas de presentación es importante para el éxito en el manejo de estas lesiones vasculares

Benign vascular lesions are mainly hemangiomas and vascular malformations. Knowing the different clinical presentations is extremely important and will allow making the right diagnosis and, in consequence, applying the proper treatment

Morphological characterization of the anuran integument of the Proceratophrys and Odontophrynus genera (Amphibia, Anuran, Leptodactylidae).

The morphological characteristics of the leptodactylid integument of Proceratophrys and Odontophrynus genera were investigated by means of stereoscopic, low vacuum scanning electron and light microscopy. The integument surface of Proceratophrys boiei, Proceratophrys laticeps and Proceratophrys appendiculata exhibited several projections, while the integument of Odontophrynus americanus had rounded elevations with smooth profile. Light microscopic observations showed the basic integument morphology for all anurans, i.e., an epidermis and a dermis, which is subdivided into a spongious layer and a compact layer. The epidermis is formed by basal, intermediary and cornified layers. However, in Proceratophrys genus the cornified layer had an irregular outline, while in O. americanus the external surface was smooth. In the spongious dermis, mucous and venom exocrine glands were observed, but in O. americanus an exclusive glandular type with apocrine secretory pattern was identified. The integument morphology showed peculiar characteristics that may be helpful for genus distinction. Thus, morphological methods may be considered as an efficient means to characterize and to differentiate anuran genera.

Patología del pie en la lepra

La apetencia de la lepra por afectar la piel y el sistema nervioso pariférico de las partes más acras, conduce a que el pie sea, frecuentemente, afectado, tanto de lesiones cutáneas como neurales. Se exponen las diferentes lesiones, siendo las más importantes las neurotróficas como úlceras plantares, tarso disociado y lesiones osteo-articulares, que son causa de discapacidad y necesidad de hospitalización e importantes escollos para la reinserción social.