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Chlamyphorus truncatus is the smallest known armadillo, weighing about 100 grams and measuring less than 15 cm from head to tail. It is endemic to central Argentina and the species is named after its unique carapace. This armadillo has almost completely subterranean habits and, unlike all other subterranean mammals, C. truncatus has a carapace composed of osteoderms and cornified scales. Furthermore, the skin and carapace show unique characteristics compared even with other armadillos. Owing to the reduced development of its eyes, it is important to analyse the skin morphology of this species, as well as specialized sensory organs like vibrissae. The aim of this contribution is to describe the histomorphology of the integumentary system of C. truncatus. For this, histological sections of the skin with and without osteoderms were made, and routine histological and immunohistochemical techniques were performed. Furthermore, microCTs were performed on osteoderms to describe their micromorphology. Our results show that the integumentary system presents unique characteristics compared to other armadillos, such as the peculiar skin under the dorsal shield and the flexibility of almost all of its carapace. Furthermore, the modification of the arrangement of hairs in the first pelvic buckler osteoderms may suggest biomechanical adaptations, such as an improvement in the displacement through the tunnels of sandy soils. The skin without osteoderms presents convergent characteristics with that of other subterranean mammals. Furthermore, the vibrissae conserve the structure of the armadillos (the cavernous sinuses extend throughout the follicle‐sinus complex) with a thinning and shortening of the hairs, which are probably linked to passive monitoring of the surrounding environment. Evidently, the adaptations of subterranean mammals to their environment imply structural and functional changes, which are both regressive and progressive in nature. [ABSTRACT FROM AUTHOR]

Contents The lectin-binding pattern was compared in the normal and pathological uterus of sows during the ovarian cycle. The following biotinylated lectins were used: Con A, DBA, SBA, PNA, RCA-I, UEA-I and WGA. Glycoconjugate labelling showed differences between phases of ovarian cycle and presence of morphologic lesions. Cystic endometrial hyperplasia increased the RCA-I reaction in the apical region of the glandular epithelium. There was higher intensity of labelling of WGA in the glandular epithelium in uteri with endometritis. In addition, increased Con A binding in the glandular epithelium and mild reduction of UEA-I reactivity in the glycocalyx of the glandular epithelium were detected in the cases of endometritis. The results of this study show that morphologic alterations modify the sugar pattern in the porcine uterus. These modifications in glycoconjugates may be one of the reasons for decreased fertility in sows. [ABSTRACT FROM AUTHOR]

In a previous paper we reported that the presence of the hepatocellular carcinoma SS1K in host mice resulted in an earlier appearance of the hepatocyte mitotic peak during liver regeneration after a partial hepatectomy as well as in an increase in the amplitude of that mitotic wave. In the present work we analyse the effect of another hepatocellular carcinoma, the ES12a (HCES12a). Adult male mice of the C3H/S strain standardised for circadian-periodicity analysis, were used. One group received a subcutaneous graft of the HCES12a tumor, while another group served as control. Fifteen days later, all animals were submitted to a partial (70%) hepatectomy at 10:00 h and beginning at 16:00 h lots of between 5 and 9 host and control animals each were sacrificed at 4 h intervals until 16:00 h on the third day thereafter. All mice were injected with 2 microg/g colchicine 4 hrs before killing, and samples of livers were processed for hematoxylin-eosin staining. We determined the hepatocyte mitotic index for each animal and the mean value +/- the standard error of the mean for each lot. The peak of mitotic activity in the tumor-bearing animals took place four hours earlier than in control mice but the average values of hepatocytic mitotic activity were similar in both groups