Severe hepatitis resulting from toxoplasmosis in a barred owl (Strix varia) from Québec, Canada

A female adult barred owl (Strix varia) had been hurt by a car. Its general status declined gradually within 2 wk with anorexia and inactivity. Necropsy examination revealed marked multifocal pale areas in liver, emaciation, and mild airsacculitis and pericarditis. Histopathologic examination revealed severe acute multifocal hepatic necrosis with numerous protozoal tachyzoites within necrotic foci and in the cytoplasm of hepatocytes and macrophages. These tachyzoites stained with an indirect immunohistochemistry method for Toxoplasma gondii antigens. This is the first reported case of hepatitis resulting from toxoplasmosis in a raptor.     

Tawny owl (Strix aluco) and Hume's Tawny owl (Strix butleri) are distinct species: evidence from nucleotide sequences of the cytochrome b gene

The cytochrome b gene of the Tawny Owl (Strix aluco), Hume's Tawny Owl (Strix butleri) and the African wood owl (Strix woodfordii) was amplified by polymerase chain reaction (PCR) and partially sequenced (300 base pairs). Sequences differ substantially (9 to 12% nucleotide substitutions) between these taxa indicating that they represent distinct species, which is also implicated from morphological and biogeographic differences. Using cytochrome b sequences of S. aluco, S. butleri, S. woodfordii, Athene noctua and Tyto alba phylogenetic relationship were reconstructed using the "maximum parsimony" principal (PAUP 3.1.1) and the neighbour-joining method (MEGA).     

Clor vision in the tawny owl (Strix aluco).

Trained 4 tawny owls to discriminate simultaneously between blue (437 nm) and green (547 nm) lights and between red (672 nm) and green (547 nm) lights. The relative luminances of the stimulus pairs were randomly varied. This procedure, together with the results of test trials, suggests that it is highly unlikely that the discriminations were made using cues based on the luminances of the stimuli. The large number of trials to learn the discrimination and the results of various procedural changes suggest that while the tawny owl does possess color vision, the wavelength of light is not of great importance in controlling its behavior. The wavelength discrimination ability of the tawny owl is compared to that of other species, and it is suggested that color vision in the tawny owl may be mediated by either a dichromatic or an anomalous trichromatic visual system. The evolution of such a system is considered. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enteric coccidia (Apicomplexa) in the small intestine of the northern spotted owl (Strix occidentalis caurina)

Sporulated oocysts (mean dimensions = 13.0 x 10.8 microns) and sporocysts (11.3 x 5.5 microns) of a coccidian resembling Frenkelia sp. or Sarcocystis sp. were present in the lamina propria of the small intestine of a naturally-infected northern spotted owl (Strix occidentalis caurina) collected near Medford, Oregon (USA). Dimensions of these oocytes and sporocysts appear to be considerably smaller than those from other sarcocystid species with avian definitive hosts. Additionally, numerous developmental stages and unsporulated oocysts (mean dimensions 22.8 x 17.8 microns) of a possible species of Isospora also were observed in the intestinal epithelium. This constitutes the first report of enteric coccidia from spotted owls. Neither parasite appeared to cause the death of the bird.     

Electroretinographically determined spectral sensitivity in the tawny owl (Strix aluco).

Obtained the electroretinographic (ERG) responses to single light flashes and to flickering lights in the tawny owl (Strix aluco), using 2 tawny owls from 300 that had been in captivity 6 mo. The waveform of the single-flash responses indicated that the owl possesses a duplex retina. Spectral sensitivity was determined with light flickering at 6 and 25 Hz. The sensitivity curve obtained from the 6-Hz responses had a broad maximum between 500 and 525 nm. The 25-Hz sensitivity curve was narrow with a peak at about 600 nm. The sensitivity curves were compared with behaviorally measured sensitivity curves of the same species and with ERG-measured sensitivity curves of the pigeon. A close agreement was found between 25-Hz curve and the pigeon red modulator. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maturation of the blood-retina barrier in the developing pecten oculi of the chicken

The major interest in the development of the blood-brain barrier and its underlying induction mechanisms is given by the crucial role they play in the maturation of the central nervous system in general. Whilst it is believed that it is the microenvironment in the brain that destines the endothelial cells to become committed to barrier properties, the analysis of the multitude of factors probably responsible for this commitment is extremely difficult. Therefore, in a previous study, we inaugurated the pecten oculi of the avian eye as a relatively simple in vivo model of the blood-brain barrier [Gerhardt, S. et al, Cell Tissue Res., 285 (1996) 91-100]. In the present study, we demonstrate data on the development of the pecten which allow us to understand better the commitment of barrier properties in endothelial cells in an environment which is considerably less complex than that realized in the brain. The pecten is built up by mainly two cell types, the pigmented glial cells and the endothelial cells. The pigmented cells, which are believed to originate from the retinal pigment epithelium, lose their tight junctions in the microenvironment of the vitreous body, whereas the endothelial cells, which originate from the permeable choroidal vessels, gain tight junctions and other barrier properties in the microenvironment of the vitreous body. On embryonic day 7 (E7), tight and gap junctions between epithelial-like glial cells line the vitreal border of the developing pecten. By E16, these junctions disappear, and the endothelial cells gradually acquire barrier characteristics (continuous and P-face associated tight junctions, no extravasation of lanthanum nitrate, and the exclusive expression of the glucose transporter isoform 1 and the barrier specific antigen HT7 in their luminal and abluminal membranes). The results are discussed considering the switch from an epithelial (glial) to an endothelial barrier.     

Fine structure of the spermatozoa of Crassostrea gigas (Mollusca, Bivalvia)

STUDY OBJECTIVES: To compare the effectiveness of intramuscular meperidine (2 mg/kg) and promethazine (1 mg/kg) with chlorpromazine (MPC) or without chlorpromazine (MP) (1 mg/kg) for sedation of children undergoing emergency department procedures. DESIGN: Randomized, double-blind trial. SETTING: A community and university hospital ED. TYPE OF PARTICIPANTS: Eighty-seven hemodynamically and neurologically stable children less than 16 years old. INTERVENTIONS: IM sedation followed by intended procedure. MEASUREMENTS AND MAIN RESULTS: Children receiving either combination were not significantly different with regard to age, sex, weight, chronic illness, and indications. Procedures included laceration repair (46), fracture reduction (25), and others (16). Mean onset of action was similar (16 +/- 12 minutes), whereas the duration of action was significantly longer after MPC (63 +/- 57 minutes [mean +/- SD] compared with MP 29 +/- 36 minutes; P < .05, Student's t-test). Paradoxical hyperactivity occurred only after MP (three of 43 cases; P = NS, Fisher's exact test), whereas transient oxygen desaturation occurred only after MPC (one of 44 cases; P = NS). No other serious complications were observed. Three observers rated the effectiveness of sedation and analgesia on separate 10.2-cm visual-analog scales. Overall, MPC received significantly better ratings (7.4 +/- 2.1 cm) than MP (5.7 +/- 3.0 cm; P < .05, Mann-Whitney U test). Parents believed sedation worked well in 90% of cases. Their children had bad memories of the procedure in only 9% of cases. CONCLUSION: Elimination of chlorpromazine from the IM combination of meperidine and promethazine for pediatric sedation during ED procedures results in a significant reduction in efficacy.     

Fine structure of the ocellus of the cabbage looper moth (Trichoplusia ni)

The dorsal ocelli of adult cabbage looper moths were studied by light microscopy, and scanning and transmission electron microscopy. Each ocellus has a cuticular lens located on the distal end of a cuticular cone which encapsulates the receptor cells. There are two distinct types of receptor cells in the ocellus. Seventy large receptor cells from plate-like rhabdoms with several adjacent cells to produce a rhabdom network in the ocellus. Proximally ninety small receptor cells which have a disorganized microvillar rhabdomere are located at the base of the rhabdoms formed by the large cells. Extensive areas of gap junctions which occur between the rhabdoms and the membranes of large and small cells suggest that the cells may be electrically coupled to one another. Axons from both large and small receptor cells leave the base of the ocellus and extend to the protocerebrum to synapse with second order neurons.     

Fine structure of the first optic ganglion (lamina) of the cockroach, Periplaneta americana

The stuctural organization of the first optic ganglion (lamina) of the cockroach (Periplaneta americana) was investigated by the use of light and electron microscopy. Each compound eye of the cockroach is composed of up to 2000 visual units (ommatidia) of the fused rhabdom type. The ommatidia themselves consist of eight receptor cells which terminate as axons in either the first or second optic ganglion. Three different short visual fibre types end in two separate strata in the lamina, and one long fibre type ends in the second optic ganglion. Monopolar second-order neurons with wide field branching patterns in the middle stratum of the first synaptic region have postsynaptic contacts with sort visual fibres. Horizontal fibre elements with branching patterns at different levels of the lamina apparently from three horizontal plexuses with presynaptic and/or postsynaptic connections to first-and second-order neurons. The lack of well-organized fibre cartridges containing a constant number of first and second order neurons in each fascicle and the presence of only unistratified wide field monopolar cells could represent, as compared to other insect orders, a primitive stage in the development of the first optic ganglion.     

Fine structure of postgonopodial glands of a myriapod Glomeris marginata (Villers)

The postgonopodial gland of the myriapod Glomeris marginata (Villers), which produces a pheromone, is an integumentary gland comprising numerous functional secretory units. Each secretory unit consists of two proximal secretory cells, an intermediary cells lacking secretory characteristics and a canal cell surrounding the canal, which is secretory in nature. Secretory proximal cells exhibit a zone of small channels originating from invaginations of the plasma membrane and through which secreted material is released. Apposing each invagination of these cells is a corresponding invagination of the intermediary cell: the two units in the centre of the intermediary cell join another which communicates with the canal. Secretion produced by the latter passes through the canal wall and bends with secretion of the two proximal cells. The most striking feature of all these cells is the abundance of tubules and fibrils in the small canal zone in the proximal cells, which also exhibits a centriole; in the intermediary cell around cytoplasmic membrane invaginations where a diplosome is present, and in almost the entire canal cell.     

Fine structure of the retinal pigment epithelium in the Port Jackson shark (Heterodontus phillipi)

The structure of the retinal epithelium (RPE), choriocapillaris and Bruch's membrane (complexus basalis) has been studied by light and electron microscopy in the Port Jackson shark (Heterodontus phillipi). In this elasmobranch the RPE consists of a single layer of low cuboidal cells which show basal (scleral) infolding and apical (vitreal) processes that enclose photoreceptor outer segments. Laterally these epithelial cells are joined by a series of apically located tight junctions. The RPE cells display a large vesicular nucleus, abundant smooth endoplasmic reticulum as well as numerous polysomes and mitochondria. Phagosomes are present, rough endoplasmic reticulum is scarce and myeloid bodies were not observed. Melanosomes are absent over the choroidally located tapetum lucidum, but are not abundant even in extratapetal areas. This paucity of melanosomes probably makes retinomotor movements unimportant. Bruch's membrane or complexus basalis is a pentalaminate structure. The endothelium of the choriocapillaris is thin but minimally fenestrated.     

Fine structure of a freshwater teleost (Pimelodus maculatus) intrahepatic biliary pathways

The intrahepatic biliary passages of a teleost liver composed by a muralium duplex was studied by electron microscopy. The bile canaliculus was commonly formed by 2 or more hepatic cells. In the transition zone between the intercellular bile canaliculus and the bile ductule, this duct was formed in part by hepatic cells and in part by duct cells. While the number of duct cells increased, the number of hepatocytes decreased until the entire ductule was formed by 2 or 3 duct cells. Bile duct was formed only by pyramidal duct cells. These cells are readily distinguished from the hepatocytes by its irregular shape, by a paucity of organelles and by the abundance of microfilaments.     

Significance of the pecten band in anorectal surgery

Constricting fibrous tissue in the subepithelial tissue of the terminal anus found at operation should be partially resected. Postoperative anal stenosis is prevented thereby, and superior functional and anatomic end results are attained.     

Fine structure of the olfactory organ of elasmobranchs (Elasmobranchii)]

The study acetylene amines were capable of inhibiting the processes of lipids peroxidation both in the enzymatic and non-enzymatic peroxidation system. The inhibitory effect of the study compounds depended upon the degree of the compound unsaturation. An elevation of the unsaturation degree to a definite extent is attended also by an increased inhibitory action on the processes of the lipids peroxidation.     

Fine structure of the human ceruloplasmin gene

We characterized the genomic region corresponding to the human ceruloplasmin cDNA previously reported. Using PCR-direct sequencing methods, we determined precise intron/exon boundaries and intron-exon composition of the gene in the region. The gene region spanned about 50 kb and was composed of 19 exons and 18 introns. The lengths of exons and introns range from 107 to over 267 bp and from 0.44 to 10.0 kb, respectively. The translation initiation codon and the termination codon were located in exons 1 and 19, respectively. The nucleotide sequences of the introns were also determined in the region around the intron/exon boundaries for 24-220 bp. All the sequences around the intron/exon boundaries were consistent with the 5' and 3' consensus sequences for splice junctions of transcribed genes. Putative lariat sequences were identified between -17 and -42 nucleotides from the 3' splice junction for all 18 introns.     

Fine structure and distribution of antennal sensilla of the desert locust, Schistocerca gregaria (Orthoptera: Acrididae)

The basic science immunology community is quite accepting of the phenomenon of oral tolerance induction in animals; however, in contradistinction, the clinical community is somewhat agnostic regarding oral tolerance. Progress in multiple sclerosis has not been definitive and outcomes in RA have been modest at best. Recent reports in animal models have suggested that oral ingestion of autoantigen can have deleterious effects on the host. Although those experiments have had a highly artificial framework, they are consistent with the possibility that oral antigen therapy in human disease may be: (1) beneficial; (2) of no consequence; or (3) detrimental. An extremely open mind will hopefully be applied to future research efforts.     

Hearing in the owl monkey (Aotus trivirgatus): I. Auditory sensitivity.

Determined pure-tone absolute thresholds for 2 male owl monkeys using a tracking procedure. The owl monkey audibility curve obtained had best sensitivity at 8-10 kHz and +40-db sound pressure level (SPL) cutoffs at 125 Hz and 42 kHz. The high-frequency slope was very sharp, the +70-db SPL cutoff occurring at 46 kHz. A comparison of the nocturnal owl monkey with the closely related but diurnal squirrel monkey revealed that their audibility functions are remarkably similar. Comparison of audibility functions of nocturnal and diurnal primates suggests that there is no inevitable specialization of auditory sensitivity in nocturnal species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)