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PubMed1987

[Study of the hepatobiliary system using 75Se-methionine in chronic hepatitis in remission].

The investigation of 43 patients with diffuse liver diseases in remission has shown that the results of studies on the hepatobiliary system using 75Se-methionine possess the highest informative value. These results were compared with those of a biochemical blood analysis and echolocation. In the absence of evident deviations from the results of biochemical blood tests and suspected diseases of the liver and biliary tracts the authors recommended first an investigation with methionine, and then depending on results, the use of other methods.

Adult↗

PubMed1986

Binaural response organization within a frequency-band representation of the inferior colliculus: implications for sound localization.

The auditory system of the mustache bat (Pteronotus parnellii) contains a disproportionately large representation of a narrow frequency band, corresponding to the dominant, 60 kHz component of its echolocation signal. In the inferior colliculus (IC), the 60 kHz representation comprises an architectonically distinct region called the dorsoposterior division (DPD), which is accessible for detailed physiological study. We examined the topographic distribution of binaural responses within this one frequency-band representation of the inferior colliculus. We describe two primary results. First, neurons with different binaural response properties are spatially segregated into one of four binaural response-specific regions of the DPD: a large region of monaural (EO) responses; two regions containing neurons excited by sound from both ears (EE); and a region containing neurons excited by one ear and inhibited by the other (EI). Regions dominated by 60 kHz EI responses are also found in the lateral extremity of the IC, probably within the external nucleus. These results demonstrate functionally defined subdivisions in a single frequency-band representation of the IC. Moreover, they suggest that brain stem auditory projections to the DPD and/or intrinsic connections within the DPD are highly organized. Second, within the EI region of the DPD, there is a systematic shift in the sensitivity of EI multiunit responses to interaural intensity disparities (IIDs). Dorsally, EI neurons are suppressed only by relatively loud ipsilateral sounds, and there is a systematic decrease in the relative ipsilateral intensity required for suppression at more ventral recording sites. This result demonstrates that neurons sensitive to a sound localization cue are systematically organized within a frequency-band representation of the inferior colliculus. It has implications for the manner in which the location of a sound source is encoded within the primary auditory pathway.

Animals↗

PubMed1985

[Intraoperative ultrasonic diagnosis of choledocholithiasis].

A method of intraductal detection of calculi with the help of ultrasound was used. Ultrasonic probes were employed for the introduction into bile ducts and their sonification from the inside. A comparative analysis of intraoperative methods of detecting biliary calculi was made: the intraoperative cholangiography could reveal the calculi in 86,8% of the observations, the intraductal echolocation--in 94,7% of the observations.

Cholangiography↗

PubMed1985

[Space-occupying masses in the right atrial cavity. Findings in segmental echo scanning].

A total of 1665 patients were examined with the aid of two-dimensional echocardiography scanning. Of these, 3 patients had sizable formations in the right atrium. During scanning, the sizable formations were recorded within the planes of echolocation, whereas the use of one-dimensional echocardiography enabled a sizable formation to be detected but in one patient. In two patients, the sizable formations were mobile and shifted during diastole to the right ventricle. In one patient, the sizable formation was immobile and was detectable only in the right atrium. The mobile formations are likely to be myxomas, whereas the immobile ones are formed by thrombotic masses.

Adult↗

PubMed1979

[Surgical treatment of pancreatic cysts].

The authors observed 103 cases of pancreatic cysts caused by acute pancreatitis, aggravation of chronic pancreatitis (81.0%) and trauma to the pancreas (12.0%). The posttraumatic cysts were more common in children and young adults (86.0%). The use of the complex method of diagnosis (x-ray examination of the gastrointestinal tract, celiacography, and upper mesentericography, endoscopic pancreatography, ultrasound echolocation of the pancreas) allowed to establish the diagnosis in 91.6% of cases. The external drainage of the cysts was carried out in cases of infected cysts with poorly formed walls. In case of a dilated and deformed main pancreatic duct with disorder of its patency (21 cases) the longitudinal cystopancreatojejunostomy was performed. The lethality after internal drainage constituted 2.4%. 80.8% of patients showed good long-term results of the treatment and 14.4%--showed fair results. 2 patients (2.1%) developed the recurrence of the cyst.

Adult↗

PubMed1979

[Polycystosis of the liver].

The authors operated 15 cases with polycystotic liver. The diagnostic value of ultrasound echolocation and hepatoscanning in polycystosis was noted. In authors' opinion the surgical treatment of polycystotic liver should be carried out in due time during the clinical manifestations phase and ought to be radical enough to yield satisfactory results.

Adult↗

PubMed1980

Prospects of regeneration in man.

Reports of fingertip regrowth in children are interpreted in the perspective of epimorphic regeneration in lower forms and in relation to a few other examples in mammals. The latter include cases of antler replacement in deer as well as ingrowth from the margins of holes cut in bat wing membranes and in the external ears of rabbits, pikas, cats, and echolocating bats. It is suggested that the relative inadequacy of regeneration in warm-blooded vertebrates may be attributed to the precocity with which they tend to form dermal scars in healing wounds, scars that are believed to preclude blastema production. Wound healing around the margins of rabbit ear holes is uniquely characterized by the development of prominent epidermal downgrowths adjacent to the severed sheets of dermis in the integument on either side of the ear. If these downgrowths act as epidermal blockades preventing scar formation in favor of allowing blastema cells to accumulate, a logical approach to the experimental induction of regeneration in normally nonregenerating mammalian appendages would involve manipulation of the mechanisms by which epidermis heals amputation stumps.

Amputation, Traumatic↗

PubMedDate not supplied

[The surgical procedure in nonparasitic liver cysts].

34 patients with middle and big size liver cysts have been undergone surgical treatment. 19 of them underwent treating puncture of the cysts. The character of operations was various and determined by the quality, size topography-anatomic cyst disposition as well as existence of associated diseases in patients. Puncture treatment has been carried out under the control of echolocation. 96% alcohol and 76% solution of verographine were used as sclerosants. The clinic experience has shown that puncture method should be applied more widely and in some cases must introduce the alternative to surgical treatment.

Adult↗

PubMedDate not supplied

[Computerized ultrasound diagnosis of internal brain damages].

The paper covers the main characteristics of a computer complex for diagnosis of cerebral lesions, which is based on ultrasonic one-dimensional echolocation. The application of current computers is shown to expand the potentialities of this well-known method to a greater extent. A simultaneous recording of A-echo with a pulseogram localizes the large vessels of the brain, which is a good supplementary tool for Doppler intracraniography. It is emphasized that the automatic processing of experimental findings substantially accelerates and simplifies an experimental process.

Brain Injuries↗

PubMedDate not supplied

[A comparative morphological analysis of the development of the ear in mammals].

This paper is the first comparative study into prenatal ontogenesis of the peripheral auditory system in mammals. A wide range of ecologically different species was studied, including terrestrial, semi-aquatic and aquatic forms with auditory systems functioning at low, medium, and high frequencies. Structural peculiarities of the development of auditory organ were determined for each studied species in relation to its operation frequency and acoustic properties of the outer medium. The origin and individual stages of morphological adaptations found in semi-aquatic, aquatic, and echolocating species are described. The data obtained allowed to reveal general principles of development of the peripheral auditory system in mammals with different ecological specialization.

Animals↗

PubMed1993

[Effect of C.P.Fëdorov's approach on morphology and function of the anterior abdominal wall according to the findings of ultrasonic examination].

Echolocation was accomplished by means of "Alok-650" echochamber (Japan) and 3.5 and 5 megahertz transducers. Twenty individuals of the control group and 40 patients who underwent operations on the extrahepatic bile ducts and the gallbladder through S. P. Fedorov's approach were examined. Morphometry was conducted of the linea alba, the broad abdominal muscles, and the rectus abdominis muscles on 5 levels in relaxation and tension of the prelum abdominale muscles. The size of the rectus abdominis muscles in the control group was found to be the same on both sides. Atrophy of the right rectus abdominis muscle was revealed in all patients who were operated on. The spread and depth of the atrophic changes varied. In most cases the muscle was atrophied along its whole length distal to the line of division. The atrophic changes were maximum (22%-62% of the thickness of the symmetric area of the left rectus muscle) for a length of 2-3 cm below the operative incision. In the zone with most marked atrophic changes the muscle loses its property of contraction in functional load of the prelum abdominale.

Abdominal Muscles↗

PubMed1999

Interaural intensity difference processing in auditory midbrain neurons: effects of a transient early inhibitory input.

Interaural intensity differences (IIDs) are important cues that animals use to localize high-frequency sounds. Neurons sensitive to IIDs are excited by stimulation of one ear and inhibited by stimulation of the other ear, such that the response magnitude of the cell depends on the relative strengths of the two inputs, which in turn depends on the sound intensities at the ears. In the auditory midbrain nucleus, the inferior colliculus (IC), many IID-sensitive neurons have response functions that decline steeply from maximum to zero spikes as a function of IID. However, there are also many neurons with much more shallow response functions that do not decline to zero spikes. We present evidence from single-unit recordings in the Free-tailed bat's IC that this partially inhibited response pattern is a result of the inhibitory input to these cells being very brief ( approximately 2 msec). Of the cells sampled, 54 of 137 (40%) achieved partial inhibition when tested with 60 msec tones, and the inhibition to these 54 cells occurred primarily during the first few milliseconds of the excitatory response. Consequently, the initial component of the response was highly sensitive to IIDs, whereas the later component was primarily insensitive to IIDs. Each of the 54 "partially inhibited" cells was able to reach complete inhibition with very short stimuli, such as simulated bat echolocation calls that invoked only the initial, IID-sensitive component. Local application of inhibitory transmitter antagonists disabled the short inhibitory input, indicating that this response pattern is created within the IC.

Acoustic Stimulation↗

PubMed2003

Expression of the Kv1.1 ion channel subunit in the auditory brainstem of the big brown bat, Eptesicus fuscus.

Voltage-gated potassium channels play an important role in shaping membrane properties that underlie neurons' discharge patterns and the ways in which they transform their input. In the auditory system, low threshold potassium currents such as those created by Kv1.1 subunits contribute to precise phaselocking and to transient onset responses that provide time markers for temporal features of sounds. The purpose of the present study was to compare information about the distribution of neurons expressing the KV 1.1 in the brainstem auditory nuclei with the distribution of neurons with known functional properties in the auditory system of the big brown bat, Eptesicus fuscus. We used immunocytochemistry and light microscopy to look at the distribution of Kv1.1 subunits in the brainstem auditory nuclei. There was prominent expression in cell types known to contain high levels of Kv1.1 in other species and known to respond to auditory signals with high temporal precision. These included octopus cells and spherical bushy cells of the cochlear nucleus and principal neurons of the medial nucleus of the trapezoid body. In addition, we found high levels of Kv1.1 in neurons of the columnar subdivision of the ventral nucleus of the lateral lemniscus and in ventral periolivary cell groups. Neurons with high levels of Kv1.1 were differentially distributed in the intermediate nucleus of the lateral lemniscus and in the inferior colliculus, suggesting that these structures contain functionally distinct cell populations, some of which may be involved in high-precision temporal processing.

Action Potentials↗

PubMed2007

Connections of functional areas in the mustached bat's auditory cortex with the auditory thalamus.

The auditory thalamus is the major target of the inferior colliculus and connects in turn with the auditory cortex. In the mustached bat, biosonar information is represented according to frequency in the central nucleus of the inferior colliculus (ICc) but according to response type in the cortex. In addition, the cortex has multiple areas with neurons of similar response type compared to the single tonotopic representation in the ICc. To investigate whether these transformations occur at the level of the thalamus, we injected anatomical tracers into physiologically defined locations in the mustached bat's auditory cortex. Injections in areas used for target ranging labeled contiguous regions of the auditory thalamus rather than separate patches corresponding to regions that respond to the different harmonic frequencies used for ranging. Injections in the two largest ranging areas produced labeling in separate locations. These results indicate that the thalamus is organized according to response type rather than frequency and that multiple mappings of response types exist. Injections in areas used for target detection labeled thalamic regions that were largely separate from those that interconnect with ranging areas. However, injections in an area used for determining target velocity overlapped with the areas connected to ranging areas and areas involved in target detection. Thus, separation by functional type and multiplication of areas with similar response type occurs by the thalamic level, but connections with the cortex segregate the functional types more completely than occurs in the thalamus.

Acoustic Stimulation↗

PubMed1980

Neuromorphometric features and dimensional analysis of the vestibular end organ in the little brown bat (Myotis lucifugus).

Neuromorphometric parameters of the vestibular system were determined from serial sections of temporal bones from four little brown bats. Well-developed eminentiae cruciatae project from the cristae ampullares of the anterior and posterior membranous ampullae. A total of 4,500 bipolar ganglion cells were enumerated within the vestibular ganglion. The widths of the cell somas varied from 2.5 to 20 micrometers, with 70% of them having widths between 5.0 and 12.5 micrometers. Two maxima were observed in a curve of ganglion cell density as a function of the length of the ganglion. The first maximum indicated a density of 4,800 cells per mm2 at a length 0.20 from the apex of the ganglion (in the pars dorsalis); the second, a density of 4,750 cells per mm2 at 0.38 mm (in the pars ventralis). The morphometric parameters studied were the radii of curvature of the semicircular ducts, the cross-sectional diameters of the semicircular canals and ducts, the dimensions of the cristae ampullares and their membranous ampullae, and dimensions pertaining to the statoconial organs. Surface areas (measured from graphic projections) were determined as 0.098 mm2 and 0.016 mm2 and hair cell count 500 and 1,300 cells for the saccular and utricular maculae, respectively. The radii of curvature of the three semicircular ducts, R, were dissimilar, with the anterior duct having the largest radius (R = 0.91 mm) and the posterior duct the smallest one (R = 0.69 mm). The average cross-sectional diameters of the anterior, lateral, and posterior ducts were measured as 0.11 mm, 0.14 mm, and 0.13 mm, respectively. Some of the morphological parameters were used to ascertain information regarding the dynamics of semicircular--canal function. In particular, the coefficients theta and II in the torsion pendulum model (Steinhausen, '31; Egmond et al., '49), and the time constants xi L congruent to II/delta and xi S congruent to theta/II of the torsion pendulum model were estimated for the little brown bat from these parameters. Where appropriate, comparisons were made to time constants obtained for other species.

Animals↗

PubMed1989

Functional organization of mustached bat inferior colliculus: I. Representation of FM frequency bands important for target ranging revealed by 14C-2-deoxyglucose autoradiography and single unit mapping.

The representation in the inferior colliculus of the frequency modulated (FM) components of the first (25-30 kHz) and second (50-60 kHz) harmonic of the sonar signal of the mustached bat, which may be important for target range processing, was investigated by using the 2-deoxyglucose (2-DG) technique and single-unit mapping. In the 2-DG experiments, bats presented with second harmonic FM stimuli alone showed uptake of label in specific regions of the central nucleus and dorsal cortex of the inferior colliculus, and the nucleus of the brachium. In the central nucleus, a dorsoventrally and mediolaterally elongated slab at the caudal border of the anterolateral division was observed. Labeling in the dorsal cortex was contiguous with this band. Bats stimulated with pairs of first and second harmonic FM stimuli separated by short time delays showed similar patterns of labeling, with the addition of another dorsoventrally elongated region of uptake in the more rostral part of the anterolateral division, associated with label in the dorsal cortex. By comparison to control cases exposed to delayed pairs of first and third harmonic signals, or to a second harmonic constant-frequency tone burst at the bat's reference frequency (ca. 60 kHz), we deduced that this additional region of uptake was attributable to the first harmonic FM component. To elucidate further the details of the tonotopic organization and to correlate the frequency representation with anatomical features of the IC, fine-grained maps of single-unit best frequencies were obtained in the central nucleus. Isofrequency contours were reconstructed by computer from five bats after focal, iontophoretic injection of horseradish peroxidase to locate the penetrations and trace connections of the FM2 area. We found that the tissue volume representing FM2 frequencies (50-60 kHz) showed approximately a sixfold overrepresentation for this frequency band. This region occupied most of the caudal portion of the anterolateral division of the central nucleus. Only a single tonotopic representation was found in the central nucleus, consistent with the pattern seen in other mammals. However, isofrequency contours in the anterolateral division were oriented dorsoventrally, approximately parallel to the coronal plane. The small band of frequencies (ca. 60-62 kHz) associated with the dominant constant-frequency component of the biosonar signal was even more dramatically overrepresented (40x) and was confined to the dorsoposterior division, as previously reported by Zook et al. (1985, 530-456).(ABSTRACT TRUNCATED AT 400 WORDS)

Acoustic Stimulation↗

PubMed1992

Projections to the medial superior olive from the medial and lateral nuclei of the trapezoid body in rodents and bats.

In this study we present direct evidence of axonal projections from both the medial and lateral nuclei of the trapezoid body to the medial superior olive. Projections were traced by intracellularly labeling cells and axons in a tissue slice preparation of two rodent species, Mus musculus and Meriones unguiculatus and two bat species, Eptesicus fuscus and Pteronotus parnellii. The main axon of most principal cells in the medial nucleus of the trapezoid body gives off one or more collateral branches which arborize within the medial superior olive. These collateral axons form small bouton-like swellings which primarily contact somata within the central cell column in the medial superior olive. Likewise, labeled elongate and multipolar cells of the lateral nucleus of the trapezoid body send axons to both the medial and lateral superior olives. These axons also form perisomatic contacts in both target nuclei. These two sets of projections may relay ascending input to the medial superior olive and the lateral superior olive; the medial nucleus of the trapezoid body is known to relay input from the contralateral ventral cochlear nucleus, and the lateral nucleus of the trapezoid body may relay input from the ipsilateral ventral cochlear nucleus. These projections offer two routes for indirect, possibly inhibitory input to reach the medial superior olive from both cochlear nuclei. These indirect, inhibitory pathways may parallel the direct excitatory projections the medial superior olive receives from each cochlear nucleus.

Animals↗

PubMed1975

Experimental studies of the ontogeny of ultrasonic vocalizations in bats.

The ontogeny of FM pulses emitted by bats is a process of maturation that is not easily altered by experimental manipulation during early development. Infants that were hand-raised and infants that were raised by mothers with altered voices (the superior laryngeal nerves were cauterized pre- and postpartum) emitted normal adult calls. Effects of pinching the superior laryngeal nerves of young bats with a cold forcepts on their vocalizations suggest that the development of this nerve and its associated musculature occurs early in the bat's postnatal life.

Animals↗