Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BATS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,387 records · Page 77Linked to original sources
PubMed1977

Encephalization and quantitative brain composition in bats in relation to their life-habits.

A quantitative analysis of the brains of 43 bat species is presented. Eleven brain components were studied. The species were arranged according to seven distinct dietary groups and it was found that the relative development of the principal components is related to those groups. The importance of neocorticalization as a reflection of evolution of all the bats in contrast to specialization in some species is stressed. This work gives a clearer view of Chiropteran progressiveness or primitiveness: the insectivorous forms occupy the least advanced, although most specialized, level; the vampires, the carnivorous species and the flying foxes are at the top of the scale. The importance of behaviour and the relative development of the central nervous system in the hierarchial classification of mammals is stressed.

Animals↗
PubMedDate not supplied

[Isolation of the Lagos-bat virus in the Central African Republic].

The second reported isolate of Lagos-bat virus has been obtained from bats Micropterus pusillus caught in 1974 in the Central African Empire, thus extending the geographic area of this virus and adding another species of vertebrate host among its reservoirs.

Animals↗
PubMed1980

Production of primate D-type virus interspecies-specific antigen during cocultivation of human breast fibroadenoma cells with bat lung cells.

Nine human breast fibroadenomas, initially negative for D-type retrovirus interspecies-specific antigen, do not produce that antigen during 6 months of cocultivation with bat lung cells. However, 3 out of 5 human breast fibroadenomas, already positive for D-type virus interspecies-specific antigen before cultivation, are able to induce a transient D-type retrovirus interspecies-specific antigen production after 3 to 4 months of cocultivation with bat lung cells. The antigen is detectable both in cocultivated cells and in pellets sedimented from the coculture fluid. It is concluded that D-type retroviruses are associated with human breast fibroadenomas.

Adenofibroma↗
PubMed1984

[Ultrastructural aspects of testicular interstitial cells in the bat (Vesperugo savi)].

The fine structure of the testicular interstitial cells (Leydig cells) was studied in the bat (Vesperugo savi) during the seasons in connection with his peculiar spermatogenesis activity and biologic cycle. Such cells have ultrastructural aspects similar to those delineated for the other species. Only the smooth endoplasmatic reticulum, mitochondria and lipid droplets changes their morphologic features during the year. In fact in the summer-autumn season there is an intense spermatogenesis. The Leydig cells show more developed smooth endoplasmatic reticulum and lipid droplets of different size of peripheral electron-density. During the winter-spring season there is not spermatogenesis. The testicular interstitial cells have a poor smooth endoplasmatic reticulum and numerous bodies like lipofuscin pigments. When the bat wakes from his lethargic sleep, the ultrastructural aspects of Leydig cells are the prove of a smaller synthesis activity. These results confirm the dependence of testicular interstitial cells from the spermatogenic cycle.

Animals↗
PubMed1978

A collagen and elastic network in the wing of the bat.

Bundles of collagen fibrils, elastic fibres and fibroblasts are organized into a network that lies in the plane of a large portion of the bat wing. By ultrastructural (TEM and SEM) and biochemical analyses it was found that individual bundles of the net are similar to elastic ligaments. Although elastic fibres predominate, they are integrated and aligned in parallel with small bundles of collagen. A reticulum of fibroblasts, joined by focal junctions, forms a cellular framework throughout each bundle. Because of the unique features of the fibre bundles of the bat's wing, in particular their accessibility, and the parallel alignment of the collagen fibrils and elastic fibres in each easily isolatable fibre bundle, they should prove a most valuable model for connective tissue studies, particularly for the study of collagen-elastin interactions.

Amino Acids↗
PubMed1984

Effect of L-dihydroxyphenylalanine (L-dopa) and methionine on tissue S-adenosylmethionine concentrations in cobalamin-inactivated fruit bats.

The fruit bat Rousettus aegyptiacus develops cobalamin deficiency when exposed to the gas nitrous oxide (N2O). The effect of dietary methionine (600 mg/kg fruit) or L-3, 4-dihydroxyphenylalanine (L-dopa, 100 mg/kg body weight daily) on brain and liver S-adenosylmethionine (AdoMet) concentrations, and on the neurological impairment was studied. Methionine supplementation significantly delayed the onset of neurological impairment (p less than 0.01) and resulted in a 2.4 fold increase in liver AdoMet levels. Brain AdoMet levels were unchanged. L-dopa, which is methylated by means of AdoMet did not aggravate the N2O-induced neuropathy but did lower, albeit insignificantly, brain AdoMet levels. The results do not support the hypothesis that the neurological impairment and death in cobalamin inactivated bats is a result of a depletion of methionine or AdoMet in the nervous system.

Animals↗
PubMed1982

Encoding of target range and its representation in the auditory cortex of the mustached bat.

The time course of acoustic events is a critical element for the recognition of biologically meaningful sounds. Echolocating bats analyze the time intervals between their emitted biosonar pulses and the echoes returning from objects to assess target distance (range). In this study, we have explored the auditory cortex of the mustached bat, Pteronotus parnellii rubiginosus, using pairs of acoustic stimuli mimicking the multiharmonic biosonar signals (pulses) used by this species and their echoes. A discrete field of auditory cortex dorsorostral to the tonotopically organized primary field contains neurons which are insensitive to pure tone, frequency-modulated (FM), or noise stimuli presented singly. Rather, they respond strongly to pairs of stimuli, specifically, the fundamental FM component of the pulse paired with an FM component of one of the higher harmonics of the echo. We call these neurons FM1-FMn facilitation neurons. There are three separate longitudinal clusters in this cortical area containing FM1-FM2, FM1-FM3, and FM1-FM4 neurons, respectively. Moreover, FM1-FMn neurons are specifically sensitive to the time delay between the two FM components, i.e., the time delay of the echo from the pulse. Thus, they can decode target range. Two types of delay-sensitive neurons were found. Tracking neurons, whose response to echo delay varied according to repetition rate and stimulus duration, were found rarely. Delay-tuned neurons, which were tuned to specific time delays (best delays) of the echo from the pulse, were much more evident. Both types of neurons are organized into columns with similar best delays, and the best delay of delay-tuned neurons was found to increase systematically along the cortical surface in the rostrocaudal direction. This area, therefore, contains a neural representation of target range along this best delay axis. Such an axis exists in each of the clusters of FM1-FM2, FM1-FM3, and FM1-FM4 neurons. This is a new type of cortical organization which is not tonotopic but which represents an important acoustic cue related to the time course of acoustic events.

Animals↗
PubMed1982

Isolation of Blastomyces dermatitidis from the lungs of a bat, Rhinopoma hardwickei hardwickei Gray, in Delhi.

The isolation of Blastomyces dermatitidis is reported from the lungs of one of 155 insectivorous bats, representing Rhinopoma hardwickei hardwickei Gray, inhabiting the abandoned first floor of a school building in Old Dehli. The identity of the fungus was based on its gross and microscopic cultural morphology including demonstration of its dimorphic character. It was further confirmed by determination of the capacity of the isolate to produce the "A" exo-antigen specific for B. dermatitidis and by verification of its pathogenicity for white mice. Heretofore, B. dermatitidis has not been reported from bats. It is also the first occasion that B. dermatitidis has been isolated from animal sources in an Asian country, thereby indicating that this important dimorphic pathogenic fungus is endemic in Asia.

Animals↗
PubMed1982

[Primary structure of the hemoglobins from the Egyptian fruit bat (Rousettus aegyptiacus, Chiroptera)].

The hemoglobin of the egyptian fruit bat (Rousettus aegyptiacus) has only one component. The alpha and beta chains were separated by chromatography on CM-52 cellulose. The complete primary structures of both chains were established by automatic Edman degradation of the chains and the tryptic peptides. The alignment was done by homology with alpha and beta chains of adult human hemoglobin. A comparison of these two hemoglobins shows an exchange of 14 amino acid residues in the alpha chains and of 19 in the beta chains. These numbers are very low, considering the long phylogenetic distance between primates and megachiroptera. In the surroundings of the heme we found one substitution in each chain. In the alpha 1 beta 1-subunit interface one and two residues are exchanged respectively in the alpha and beta chains. The primary structure points to a normal oxygen affinity of the bat hemoglobin which was also found by Jürgens et al.

Amino Acid Sequence↗
PubMed1981

Distinguishing common food-contaminating bat hairs from certain feather barbules.

Differences are described between common food-contaminating vespertilionid bat hairs (Chiroptera: Vespertilionidae) and similar-appearing downy feather barbules of passeriform birds, including cuticular scales, pigment distribution, and basal characteristics. Fifteen imported food samples analyzed over a 1 1/2 year period were contaminated with these bat hairs.

Animals↗
PubMed1981

A list of ectoparasites of Colombian bats.

Of 3,860 Colombian bats, belonging to 109 species, 1,235 individuals (32%) of 100 species were infected with ectoparasites. A total of 3,545 ectoparasites pertaining to 88 species were obtained (Mesostigmata: 1 Halarachnidae; 19 Macronyssidae; 4 Spelaeorhynchidae; 104 Spinturnicidae. Ixodides: 449 Argasidae. Trombidiformes: 1 Spelognathidae; 340 Trombiculidae. Sarcoptiformes: 170 Listrophoridae. Hemiptera: 16 Cimidae; 4 Polyctenidae. Diptera: 7 Nycteribiidae; 2405 Streblidae, Siphonaptera: 25 Pulicidae). No ectoparasites were recovered from 9 species of bats.

Acari↗
PubMed1980

Comparative morphology of the accessory olfactory bulb in bats.

Bouin-perfused brains of 148 bats (76 species, 48 genera, 8 families) were examined in serial sections for the presence of an accessory olfactory bulb. A moderate to well developed AOB was identified in 26 species. However, absence of an AOB in a particular species does not preclude its presence in some other species of that genus. Descriptions and measurements of the AOBs of each species are reported. The unmyelinated vomeronasal nerve enters the bulb medially and posteriorly. The glomeruli, variable in diameter, appear better circumscribed than previously described. Mitral cells often form thick layers, up to five cells deep, which sometimes reach the dorsolateral surface of the bulb formation. Both external and internal plexiform layers are thin. The latter, however is seen only in a few species. The internal granular layer, reaching the ventricular ependyma in some species, is a prominent component of the bulb. The pars dorsalis of the lateral olfactory tract usually courses between the mitral and internal granular layers. The chiropteran AOB does not differ in significant detail from that of insectivores, primates and other mammals. The occurrence of a functional vomeronasal system in the frugivorous, nectarivorous, and sanguivorous Phyllosotomatidae points to a primary functional role of this system in feeding strategy, at least in bats.

Animals↗
PubMedDate not supplied

[Features of the reactions of neurons of the cochlear nuclei of the pointed-eared bat Myotis oxygnathus to ultrasonic stimuli].

Studies of the reactions of neurones in the cochlear nuclei in the bat Myotis oxygnathus to ultrasonic stimulation show that 61% of the investigated neurones in a frequency range 20-40 kHz change tonic response for repetitive bursts, this change being dependent on the filling frequency and the intensity of stimulation. It is suggested that peculiarities of the neuronal activity result from the effect of a special inhibitory system presented in bats which uses in echolocation a wide range frequency-modulated impulses.

Animals↗
PubMedDate not supplied

[Considerations on human rabies transmitted by bats].

The purpose of this study is to present a combined analysis of eight outbreaks of human rabies transmitted by bats in Brazil and Peru. Some factors present in many outbreaks were identified, as follows: most of the outbreaks occurred in small villages in the rural Amazonian region; there was a change of local production processes; little or no cattle was present; the houses were vulnerable; access to health services was difficult. Other information was also analyzed, for instance: attack rate; incubation period; site of the attack; occupation, sex and age of the victim. As part of the study of these recent outbreaks, a review of the bibliography on human rabies transmitted by bats was also carried out.

Adolescent↗
PubMed1993

Rabies in bat-eared foxes in South Africa.

Rabies in bat-eared foxes was first recognized in South Africa in 1955 and is likely to have been derived from canine rabies introduced to South Africa in 1950. Since then it has become established in this species in the drier western half of the country and the south-western Cape so that rabies now occurs in bat-eared foxes adjacent to the peri-urban canine population of Cape Town. Peak incidence was recorded in the early 1980s and the incidence is seasonal with most cases occurring in winter.

Animals↗
PubMed1993

[Structure and seasonal aspects of the bat gallbladder].

The gallbladder of the insectivorous hibernating bats (Pipistrellus pipistrellus et Rhinolophus ferrumequinum) in fullness, shows a fundus, a corpus and a neck. Its wall is formed by three layers: mucous membrane, with simple columnar epithelium on a thin basal lamina, beneath which is a "lamina propria" of connective tissue with blood and lymphatic vessels; lamina muscularis, constituted by three of four parallel bundles of smooth muscle cells, arranged in circular pattern; serous membrane of loose connective tissue, with precollecting lymphatic vessels and covered by mesothelial cells. By SEM the luminal surface of mucous membrane shows more or less prominent folds delimiting irregular areas with hexa-pentagonal outlines of the apical region of epithelial cells. This latter present a convex dome aspect with numerous microvilli, not changed significantly, during the different year periods. In summer and autumn the epithelial cells are characterized by developed organelles in supranuclear cytoplasm. During the prehibernating period, chiefly the cytoplasm shows multivesicular and heterogeneous dense bodies. In summer, autumn and initial hibernating period, epithelial cell cytoplasm presents microvilli with prominent "antennulae microvilares", numerous light micropinocytosis vesicles, little rough vesicles in apical portion. The mitochondria, grouping in supranuclear and basal cytoplasm, in lethargy, are characterized by small matrix osmiophilic granules. The epithelial cells are held together near the apical surface by tight and gap junctions, and some rare desmosomes only in Rhinolophus f.e. The cell membranes are deep pleated or interdigitate with wide intercellular spaces during the prehibernating period and experimental arousing, while in lethargy and summer months these present linear outline with scanty invaginations. The Authors compared these morphological aspects of bat gallbladder with other micromammalia's one, underline particularly the functional role of dense bodies, wide intercellular spaces and apical micropinocytosis vesicles. The different seasonal ultrastructural characteristics of epithelial cells are considered in close relation to an absorbing function connecting with balance of different metabolisms.

Animals↗
PubMedDate not supplied

Isolation of Listeria monocytogenes in slaughter animals and bats of Togo (West Africa).

Listeria monocytogenes was isolated from the intestinal lymph nodes of 8 out of 342 apparently healthy slaughter animals at the municipal abattoir in Lome (Togo) and from the faeces of 3 out of 236 bats. Except two strains of serovar 4b isolated from bats, all the nine others belonged to serovar 1/2a. The positive findings of slaughter animals were made from the carcasses of 2 pigs, 5 little ruminants and 1 cattle. The findings are discussed in the light of present knowledge on the occurrence of L. monocytogenes in some species of animals and its implications for the human being.

Abattoirs↗
PubMed1994

Excess positive associations in communities of intestinal helminths of bats: a refined null hypothesis and a test of the facilitation hypothesis.

The null hypothesis that the number of positive pairwise covariances should equal the number of negative pairwise covariances in samples from communities of randomly associated helminth species was reevaluated. The proportion of positive covariances in a sample from a community of independent species depends upon the proportion of rare species (prevalence less than 10%), the proportion of common species (prevalence greater than 90%), and the size of the sample of hosts. If rare species dominate, then there will be an excess of negative associations; if common species dominate there will be an excess of positive associations. Many helminth communities have more rare than common species, therefore samples from communities that show an equal number of positive and negative covariances have a greater number of positive associations than is expected for randomly associated species. Increased sample size will reduce the sampling bias, but at least 100 hosts are necessary and often 500-7,500 hosts are required. The excess of positive covariances between helminth species in 10 populations of bats disappeared after restricting the analyses to hosts in which both members of a species pair were present. This result suggests that excess positive associations between helminth species in bats are due to joint presences and absences in hosts rather than to interspecific facilitation. Interspecific facilitation would be supported by observed positive correlations between the intensities of individuals of the species pairs.

Analysis of Variance↗