Glycopatterns of the foregut in the striped dolphin Stenella coeruleoalba, Meyen 1833 from the Mediterranean Sea

AbstractThe glycopatterns of the glycans secreted by the mucosa of stomach and duodenal ampulla of the striped dolphin, Stenella coeruleoalba were studied by histochemical (Periodic acid‐Schiff, Alcian Blue pH 2.5, High Iron Diamine) and lectin‐binding (SBA, DBA, PNA, WGA, MAA‐II, SNA, ConA, UEA‐I, AAA, LTA) techniques. The stomach can be divided into four compartments: main stomach, two connecting chambers and pylorus. The pylorus is followed by the duodenal ampulla. Mucins are secreted by surface cells and intramucosal glands specific for each compartment. In the main stomach glands, neck cells were weakly sulphated, with prevailing glycosaminylated, glycosylated/mannosylated, and fucosylated residuals. Parietal and chief cells in general were scarcely reactive. In the connecting chambers glands, there were high levels of sulphation, glycosaminylation, glycosylation/mannosylation, and fucosylation, the latter with more complex patterns than those observed in the main stomach glands. In the pyloric glands sulphated, glycosaminylated and fucosylated residuals decreased, whereas the opposite was observed for galactosyl/galactosaminylated residuals. Glycosylation patterns in the glands of the duodenal ampulla differed from those of the pyloric ones, with similar levels of sulphation, lower levels of galactosyl/galactosaminylation and glycosaminylation, and higher level of fucosylation. The results are compared with those available in literature

INVESTIGATION OF PREFRONTAL AREAS IN VARIOUS ANIMAL TAXA USING DIFFUSION WEIGHTED IMAGING

The Prefrontal Cortex (PFC) has attracted a particular interest since it is the latest developed cortical area which reached its apparent maximum development in the human. Although its name came from mammalian topography, being the cortex of the anterior pole of the brain, it has been shown that even other animals, such as birds, possessed an equivalent region called Nidopallium Caudolaterale (NCL) which is involved in the same functions. These multimodal associative areas have been widely studied in humans, other primates, rodents and pigeons through several techniques. Nevertheless, neuroanatomy data of other species, in particular on fiber connections, are scarce and would deserve a deeper attention, especially for those ones largely used for meat products (like sheep, cows and pigs) whose brains are wasted and poorly investigated. Even though tracing is considered the gold standard for studying fiber connections in the brain, it is mostly used in lab animals due to ethical and practical reasons. Despite this, a relatively recent MRI technique called Diffusion Weighted Imaging (DWI) has been proven to give similar results to tracing and it is applicable not only in in-vivo specimens but also in fixed ex-vivo brains. We therefore started examining the Orbitofrontal Cortex (OFC) of the sheep (Ovis aries) and compared it with that of the human and the chimpanzee. While histology and immunocytochemistry revealed a different cytoarchitectonic and neurochemical structure, DWI showed a similarity of the areas connected to the OFC, implying that although these animals do not show the same subtlety in their complex behaviours and are commonly not revered as “smart” like primates, they still possessed the basic structures for complex abstract thought. Farm animals have undoubtedly been insufficiently examined in terms of neuroanatomy, but marine mammals certainly share this neglect, mostly due to difficulty in data collection and conservation, and ethics. In these animals the cortical map is not complete, only the visual (V1/V2), auditory (A1/A2), motor (MC) and somatosensory (SSC) cortices have been localized on the telencephalon leaving the rest of the cortical surface unassigned. To overcome this problem, we applied a new DWI technique able to detect crossing fibers within a voxel even with clinical MRI parameters, the so called constrained spherical deconvolution (CSD). This new mathematical algorithm was applied to three formalin-fixed brains of adult bottlenose dolphin (Tursiops truncatus). We first performed global tractography through several steps and then qualitatively analysed few regions. Our results confirmed the feasibility, considering the long fixation time and the clinical MRI parameters, of the CSD in ex-vivo brains. Afterwards, we sought for a putative PFC in these animals, relying in the general concept that in all mammals the PFC is the major receiver of thalamic inputs from the mediodorsal thalamic nucleus (MD). Therefore, we used the CSD to detect the fiber pathways from the MD and we proved the accuracy of our results by seeding also the lateral and medial geniculate nuclei (LGN and MGN). The reverse approach was then applied, seeding first the cortices and look for their related tracts. CSD, in accordance with the previous evoked-potential and tracing studies, confirmed the location of A1/A2 and V1/V2, together with an involvement of the LGN on A1/A2 and MGN on V1/V2. The tracts related to MD detected the possible PFC location on the orbital and cranial temporal lobes. The neocortical pattern thus suggested not only a more complex thalamic integration arrangement among different areas but also a rostrolateral rotation of the areas which probably followed the so called telescoping process which occurred to the brain case of these animals during evolution.The Prefrontal Cortex (PFC) has attracted a particular interest since it is the latest developed cortical area which reached its apparent maximum development in the human. Although its name came from mammalian topography, being the cortex of the anterior pole of the brain, it has been shown that even other animals, such as birds, possessed an equivalent region called Nidopallium Caudolaterale (NCL) which is involved in the same functions. These multimodal associative areas have been widely studied in humans, other primates, rodents and pigeons through several techniques. Nevertheless, neuroanatomy data of other species, in particular on fiber connections, are scarce and would deserve a deeper attention, especially for those ones largely used for meat products (like sheep, cows and pigs) whose brains are wasted and poorly investigated. Even though tracing is considered the gold standard for studying fiber connections in the brain, it is mostly used in lab animals due to ethical and practical reasons. Despite this, a relatively recent MRI technique called Diffusion Weighted Imaging (DWI) has been proven to give similar results to tracing and it is applicable not only in in-vivo specimens but also in fixed ex-vivo brains. We therefore started examining the Orbitofrontal Cortex (OFC) of the sheep (Ovis aries) and compared it with that of the human and the chimpanzee. While histology and immunocytochemistry revealed a different cytoarchitectonic and neurochemical structure, DWI showed a similarity of the areas connected to the OFC, implying that although these animals do not show the same subtlety in their complex behaviours and are commonly not revered as “smart” like primates, they still possessed the basic structures for complex abstract thought. Farm animals have undoubtedly been insufficiently examined in terms of neuroanatomy, but marine mammals certainly share this neglect, mostly due to difficulty in data collection and conservation, and ethics. In these animals the cortical map is not complete, only the visual (V1/V2), auditory (A1/A2), motor (MC) and somatosensory (SSC) cortices have been localized on the telencephalon leaving the rest of the cortical surface unassigned. To overcome this problem, we applied a new DWI technique able to detect crossing fibers within a voxel even with clinical MRI parameters, the so called constrained spherical deconvolution (CSD). This new mathematical algorithm was applied to three formalin-fixed brains of adult bottlenose dolphin (Tursiops truncatus). We first performed global tractography through several steps and then qualitatively analysed few regions. Our results confirmed the feasibility, considering the long fixation time and the clinical MRI parameters, of the CSD in ex-vivo brains. Afterwards, we sought for a putative PFC in these animals, relying in the general concept that in all mammals the PFC is the major receiver of thalamic inputs from the mediodorsal thalamic nucleus (MD). Therefore, we used the CSD to detect the fiber pathways from the MD and we proved the accuracy of our results by seeding also the lateral and medial geniculate nuclei (LGN and MGN). The reverse approach was then applied, seeding first the cortices and look for their related tracts. CSD, in accordance with the previous evoked-potential and tracing studies, confirmed the location of A1/A2 and V1/V2, together with an involvement of the LGN on A1/A2 and MGN on V1/V2. The tracts related to MD detected the possible PFC location on the orbital and cranial temporal lobes. The neocortical pattern thus suggested not only a more complex thalamic integration arrangement among different areas but also a rostrolateral rotation of the areas which probably followed the so called telescoping process which occurred to the brain case of these animals during evolution

The orbitofrontal cortex of the sheep. Topography, organization, neurochemistry, digital tensor imaging and comparison with the chimpanzee and human

Areas dedicated to higher brain functions such as the orbitofrontal cortex (OFC) are thought to be unique to hominidae. The OFC is involved in social behavior, reward and punishment encoding and emotional control. Here, we focused on the putative corresponding area in the sheep to assess its homology to the OFC in humans. We used classical histology in five sheep (Ovis aries) and four chimpanzees (Pan troglodytes) as a six-layered-cortex primate, and Diffusion Tensor Imaging (DTI) in three sheep and five human brains. Nissl's staining exhibited a certain alteration in cortical lamination since no layer IV was found in the sheep. A reduction of the total cortical thickness was also evident together with a reduction of the prevalence of layer one and an increased layer two on the total thickness. Tractography of the sheep OFC, on the other hand, revealed similarities both with human tracts and those described in the literature, as well as a higher number of cortico-cortical fibers connecting the OFC with the visual areas in the right hemisphere. Our results evidenced the presence of the basic components necessary for complex abstract thought in the sheep and a pronounced laterality, often associated with greater efficiency of a certain function, suggested an evolutionary adaptation of this prey species

The follicle‐sinus complex of the bottlenose dolphin (Tursiops truncatus). Functional anatomy and possible evolutional significance of its somato‐sensory innervation

Vibrissae are tactile hairs found mainly on the rostrum of most mammals. The follicle, which is surrounded by a large venous sinus, is called "follicle-sinus complex" (FSC). This complex is highly innervated by somatosensitive fibers and reached by visceromotor fibers that innervate the surrounding vessels. The surrounding striated muscles receive somatomotor fibers from the facial nerve. The bottlenose dolphin (Tursiops truncatus), a frequently described member of the delphinid family, possesses this organ only in the postnatal period. However, information on the function of the vibrissal complex in this latter species is scarce. Recently, psychophysical experiments on the river-living Guiana dolphin (Sotalia guianensis) revealed that the FSC could work as an electroreceptor in murky waters. In the present study, we analyzed the morphology and innervation of the FSC of newborn (n = 8) and adult (n = 3) bottlenose dolphins. We used Masson's trichrome stain and antibodies against neurofilament 200 kDa (NF 200), protein gene product (PGP 9.5), substance P (SP), calcitonin gene-related peptide, and tyrosine hydroxylase (TH) to characterize the FSC of the two age classes. Masson's trichrome staining revealed a structure almost identical to that of terrestrial mammals except for the fact that the FSC was occupied only by a venous sinus and that the vibrissal shaft lied within the follicle. Immunostaining for PGP 9.5 and NF 200 showed somatosensory fibers finishing high along the follicle with Merkel nerve endings and free nerve endings. We also found SP-positive fibers mostly in the surrounding blood vessels and TH both in the vessels and in the mesenchymal sheath. The FSC of the bottlenose dolphin, therefore, possesses a rich somatomotor innervation and a set of peptidergic visceromotor fibers. This anatomical disposition suggests a mechanoreceptor function in the newborns, possibly finalized to search for the opening of the mother's nipples. In the adult, however, this structure could change into a proprioceptive function in which the vibrissal shaft could provide information on the degree of rotation of the head. In the absence of psychophysical experiments in this species, the hypothesis of electroreception cannot be rejected

Antitumor Activity of a Novel Fibroblast Growth Factor Receptor Inhibitor for Intrahepatic Cholangiocarcinoma

Fibroblast growth factor receptor 2 (FGFR2) might have an important role in the pathogenesis and biology of cholangiocarcinoma (CCA). We examined FGFR expression in CCA tumor specimens obtained from patients and CCA cell lines, and then determined the effects of the novel FGFR inhibitor, derazantinib (DZB; formally, ARQ 087), which is currently in clinical phase 2 trials for intrahepatic CCA. DZB inhibited the growth of CCA cell lines in a dose-dependent manner, and extracellular signal-regulated kinase 1/2 and AKT. It also activated apoptotic and cell growth arrest signaling. DZB reduced the in vitro invasiveness and the expression of key epithelial-mesenchymal transition genes. The in vitro data correlated with the expression of FGFRs in human CCA specimens by immunohistochemistry (FGFR1, 30% positive; and FGFR2, 65% positive) and the CCA cell lines assayed by Western blot analysis. These correlated in vitro studies suggest that FGFR may play an important role in the pathogenesis and biology of CCA. Our findings support the notion that FGFR inhibitors, like DZB, should be further evaluated at the clinical stage as targeted therapy for CCA treatment