Histological features of the vomeronasal organ in the giraffe, Giraffa camelopardalis

The vomeronasal organ (VNO) that preferentially detects species-specific substances is diverse among animal species, and its morphological properties seem to reflect the ecological features of animals. This histological study of two female reticulated giraffes (Giraffa camelopardalis reticulata) found that the VNO is developed in giraffes. The lateral and medial regions of the vomeronasal lumen were covered with sensory and nonsensory epithelia, respectively. The vomeronasal glands were positive for periodic acid-Schiff and alcian blue (pH 2.5) stains. The VNO comprises several large veins like others in the order Cetartiodactyla, suggesting that these veins function in a pumping mechanism in this order. In addition, numerous thin-walled vessels located immediately beneath the epithelia covering the lumen entirely surrounded the vomeronasal lumen. This sponge-like structure might function as a specific secondary pump in giraffes.

Localization of α1-2 Fucose Glycan in the Mouse Olfactory Pathway

Glycoconjugates in the olfactory system play critical roles in neuronal formation, and α1-2 fucose (α1-2Fuc) glycan mediates neurite outgrowth and synaptic plasticity. Histochemical findings of α1-2Fuc glycan in the mouse olfactory system detected using Ulex europaeus agglutinin-I (UEA-I) vary. This study histochemically assessed the main olfactory and vomeronasal pathways in male and female ICR and C57BL/6J mice aged 3-4 months using UEA-I. Ulex europaeus agglutinin-I reacted with most receptor cells arranged mainly at the basal region of the olfactory epithelium. The olfactory nerve layer and glomerular layer of the main olfactory bulb were speckled with positive UEA-I staining, and positive fibers were scattered from the glomerular to the internal plexiform layer. The lateral olfactory tract and rostral migratory stream were also positive for UEA-I. We identified superficial short-axon cells, interneurons of the external plexiform layer, external, middle and internal tufted cells, mitral cells and granule cells as the origins of the UEA-I-positive fibers in the main olfactory bulb. The anterior olfactory nucleus, anterior piriform cortex and olfactory tubercle were negative for UEA-I. Most receptor cells in the vomeronasal epithelium and most glomeruli of the accessory olfactory bulb were positive for UEA-I. Our findings indicated that α1-2Fuc glycan is located within the primary and secondary, but not the ternary, pathways of the main olfactory system, in local circuits of the main olfactory bulb and within the primary, but not secondary, pathway of the vomeronasal system.

Higher refractive index and lower wavelength dispersion of SiO2 glass by structural ordering evolution via densification at a higher temperature

Silica glasses permanently densified at high temperatures show unexpected increase of both the refractive index and the Abbe number. Glasses densified at a higher temperature underwent homogeneous evolution of their intermediate structural ordering.

Structure and functions of the placenta in common minke (Balaenoptera acutorostrata), Bryde's (B. brydei) and sei (B. borealis) whales

The structure and functions of placentas were examined in 3 species of rorqual whales, common minke (Balaenoptera acutorostrata), Bryde's (B. brydei) and sei (B. borealis) whales, with the aim of confirming the structural characteristics of the chorion, including the presence of the areolar part, and clarifying steroidogenic activities and fetomaternal interactions in the placentas of these whales. Placentas were collected from the second phase of the Japanese Whale Research Program under Special Permit in the North Pacific (JARPN II). Histological and ultrastructural examinations revealed that these whale placentas were epitheliochorial placentas with the interdigitation of chorionic villi lined by monolayer uninucleate cells (trophoblast cells) and endometrial crypts as well as folded placentation by fold-like chorionic villi. Moreover, well-developed pouch-like areolae were observed in the placentas, and active absorption was suggested in the chorionic epithelial cells of the areolar part (areolar trophoblast cells). Berlin blue staining showed the presence of ferric ions (Fe(3+)) in the uterine glandular epithelial cells and within the stroma of chorionic villi in the areolar part. An immunohistochemical examination revealed tartrate-resistant acid phosphatase (TRAP; known as uteroferrin in uteri) in the cytoplasm of glandular cells and areolar trophoblast cells. This result suggested that, in cetaceans, uteroferrin is used to supply iron to the fetus. Furthermore, immunoreactivity for P450scc and P450arom was detected in trophoblast cells, but not in areolar trophoblast cells, suggesting that trophoblast cells synthesize estrogen in whale placentas. Therefore, we herein immunohistochemically revealed the localization of aromatase and uteroferrin in cetacean placentas during pregnancy for the first time.

Genes associated with the progression of neurofibrillary tangles in Alzheimer's disease

The spreading of neurofibrillary tangles (NFTs), intraneuronal aggregates of highly phosphorylated microtubule-associated protein tau, across the human brain is correlated with the cognitive severity of Alzheimer's disease (AD). To identify genes relevant to NFT expansion defined by the Braak stage, we conducted whole-genome exon array analysis with an exploratory sample set consisting of 213 human post-mortem brain tissue specimens from the entorinal, temporal and frontal cortices of 71 brain-donor subjects: Braak NFT stages 0 (N=13), I-II (N=20), III-IV (N=19) and V-VI (N=19). We identified eight genes, RELN, PTGS2, MYO5C, TRIL, DCHS2, GRB14, NPAS4 and PHYHD1, associated with the Braak stage. The expression levels of three genes, PHYHD1, MYO5C and GRB14, exhibited reproducible association on real-time quantitative PCR analysis. In another sample set, including control subjects (N=30), and in patients with late-onset AD (N=37), dementia with Lewy bodies (N=17) and Parkinson disease (N=36), the expression levels of two genes, PHYHD1 and MYO5C, were obviously associated with late-onset AD. Protein-protein interaction network analysis with a public database revealed that PHYHD1 interacts with MYO5C via POT1, and PHYHD1 directly interacts with amyloid beta-peptide 42. It is thus likely that functional failure of PHYHD1 and MYO5C could lead to AD development.

Accumulation of eosinophils in the infundibulum of the bovine oviduct just after ovulation

This study was to investigate the localization and distribution of eosinophils (EOS) in the bovine oviduct throughout the estrous cycle. Histological studies revealed more abundant EOS in the infundibula of the oviducts ipsilateral to the preovulatory dominant follicle and the ovulated ovary. The number of EOS was higher in the infundibula of the oviducts ipsilateral to the ovulated ovary than those of the oviducts contralateral to the ovulated ovary. The infundibula of the oviducts ipsilateral to the preovulatory dominant follicle had higher number of EOS than those of the oviducts ipsilateral to the mid-cycle corpus luteum. The number of EOS in the isthmus, but not in the ampulla, was higher in the outer layers (tunica muscularis and tunica serosa) than in the inner layers (tunica mucosa and tunica submucosa) during the estrous cycle. Thus, the EOS number varied with the region of the bovine oviduct, with greater number in the infundibula of the oviduct ipsilateral to the ovulated ovary, suggesting the impact of ovulation.

Areolae of the placenta in the Antarctic minke whale (Balaenoptera bonaerensis)

In this study, we examined the existence and structure of areolae and the steroidogenesis of areolar trophoblast cells in the Antarctic minke whale placenta morphologically and immunohistochemically. Placentas were collected from the 15th, 16th and 18th Japanese Whale Research Program under Special Permit in the Antarctic (JARPA) and 1st JARPA II organized by the Institute of Cetacean Research in Tokyo, Japan. The opening and cavity of fetal areolae formed by taller columnar trophoblast cells (areolar trophoblast cells) with long microvilli and a bright cytoplasm, as compared with the trophoblast cells of the chorionic villi interdigitating with the endometrial crypts, were recognized in observations of serial sections. The opening of the areolar cavity was hidden by chorionic villi with areolar trophoblast cells. Furthermore, a closed pouch-like structure lined by tall columnar cells similar to areolar trophoblast cells within the stroma of chorionic villi was noticed and continued to the areolar cavity, with the opening seen on serial sections. In a surface investigation of the chorion and endometrium by SEM, maternal (endometrial) areolae irregularly surrounded by endometrial folds were obvious. Moreover, we distinguished areolar trophoblast cells with long microvilli attached with many blebs from trophoblast cells. In our immunohistochemical observations, a steroidogenic enzyme, cytochrome P450 side chain cleavage enzyme (P450scc), was detected with strong immunoreactivity in trophoblast cells. However, areolar trophoblast cells showed weak or no immunoreactivity for P450scc.

Effects of acute and chronic psychological stress on platelet aggregation in mice

Although psychological stress has long been known to alter cardiovascular function, there have been few studies on the effect of psychological stress on platelets, which play a pivotal role in cardiovascular disease. In the present study, we investigated the effects of acute and chronic psychological stress on the aggregation of platelets and platelet cytosolic free calcium concentration ([Ca(2+)]i). Mice were subjected to both transportation stress (exposure to novel environment, psychological stress) and restraint stress (psychological stress) for 2 h (acute stress) or 3 weeks (2 h/day) (chronic stress). In addition, adrenalectomized mice were subjected to similar chronic stress (both transportation and restraint stress for 3 weeks). The aggregation of platelets from mice and [Ca(2+)]i was determined by light transmission assay and fura-2 fluorescence assay, respectively. Although acute stress had no effect on agonist-induced platelet aggregation, chronic stress enhanced the ability of the platelet agonists thrombin and ADP to stimulate platelet aggregation. However, chronic stress failed to enhance agonist-induced increase in [Ca(2+)]i. Adrenalectomy blocked chronic stress-induced enhancement of platelet aggregation. These results suggest that chronic, but not acute, psychological stress enhances agonist-stimulated platelet aggregation independently of [Ca(2+)]i increase, and the enhancement may be mediated by stress hormones secreted from the adrenal glands.

A highly emissive inorganic hexamolybdenum cluster complex as a handy precursor for the preparation of new luminescent materials

The synthesis of a new octahedral molybdenum cluster and a cluster–polymer hybrid is described, both materials possess excellent photoluminescent properties.