[Indications for atypical papillotomy by the method of trans-pancreatic precut of the Vater's papilla in case of inability of the standard cannulation].

The analysis of our own experience of atypical endoscopic sphincterotomy by transpancreatic precut, its effectiveness is evaluated and analyzed the complications and their causes.

[Endoscopic treatment of gastric varices bleeding].

The problem of prevention of variceal bleeding (VB) of esophagus and stomach in patients with portal hypertension has not lost its relevance due to the high mortality rates (reaching 50% at relapse), as a result of the objective difficulties of implementation of efficient primary hemostasis and subsequent control of recurrent bleeding and adequate correction of coagulopathy, and decompensated liver function. Endoscopic ligation of esophageal VB latex rings or plastic endo loop continues to be the standard prevention of bleeding of portal genesis (Baveno IV, V). However, according to several authors, endoscopic ligation by latex rings should not be used in the propagation of VB on the stomach (as well as the presence of VB isolated stomach) because of the danger of destruction latex by gastric juice. At the same time, the latex ligation is much easier technically, faster, and therefore, it is easier tolerated, and most importantly, do not poses a threat to the strain varices difficult to stop the bleeding which in some cases observed at tightening of the plastic endoloop. In this study proved the possibility to reach the comparative safety and efficacy of gastric banding Varices with latex rings.

[Endoscopic treatment at cholangioscopic cholangiolitiasis].

The article shows a retrospective analysis of endoscopic cholangioscopic conducted as an independent intervention after endoscopic retrograde cholangiopancreatography, and as an auxiliary manipulation during open and laparoscopic surgery. Was demonstrated that cholangioscopic manipulation can be an effective tool both in diagnosis and in prevention and treatment of recurrent and residual cholangiolitiasis, particularly in difficult-to-standard endoscopic techniques of cases. Were refined indications for manipulation and evaluated the diagnostic value and therapeutic effectiveness of the cholangioscopic manipulations. Based on our experience, were refined features and advantages of the methodology and limitations were analyzed and the reasons for the failures and suggests ways to overcome them.

[Surgical treatment of neuromuscular diseases of the esophagus].

Surgical treatment of patients with neuromuscular diseases of the esophagus is a separate issue, and the approach to antireflux surgery they differ from fundoplication for gastroesophageal reflux disease. At the Central Research Institute of Gastroenterology in 2010 yr were 17 patients with neuromuscular diseases of the esophagus laparoscopic fundoplication. Analysis of results showed the effectiveness of laparoscopic fundoplication in patients with severe esophageal motility.

[Primary prevention of reflux esophagitis in achalasia of cardia].

Aim of the study was to compare the incidence of reflux esophagitis in patients with achalasia cardia after successful surgical treatment with balloon dilatation and ezofago-cardio-seromyotomy followed by fundoplication according toToupet type. The study included only those patients with eliminated symptoms of dysphagia. All patients were divided into two groups depending on the method of treatment. In the first group (20 patients) performed balloon dilatation, second group (20 patients)--laparoscopic ezofagocardioseromiotomiya followed by fundoplication according type Toupet. Results evaluated one year after the intervention. Revealed that the incidence of reflux esophagitis were significantly higher in group of patients after balloon dilatation, than in the group of operated patients--40 and 15% respectively (p < 0,05). Received results allow to reconsider approaches to the selection of treatment method of achalasia cardia in favor of laparoscopic ezofagocardioseromitomii with the formation of posterior cuff-type Toupet.

[Description of a clinical case of recurrent gastrointestinal bleeding, were caused by arteriovenous malformation of the stomach].

We described a clinical case of recurrent gastrointestinal bleeding caused by arteriovenous malformation of the stomach.

Effects of bupivacaine and ropivacaine on field potential in rat hippocampal slices.

BACKGROUND: In spite of more than 20 yr of research, the mechanism whereby local anaesthetics act on the brain to mediate anaesthesia still remains unclear. Furthermore, the effect of local anaesthetics on neuronal excitability and synaptic transmission in the hippocampus has not been reported. Thus, the purpose of the present study was to find out the differences between the local anaesthetics, bupivacaine and ropivacaine, in their actions on synaptic transmission of brain in the context of hippocampal field potential. METHODS: Brains were removed from 3- to 4-week-old rats and transverse slices (300 microm thick) were prepared using a microslicer. A slice was then placed on the centre on a multielectrode dish probe. To record evoked field potentials at 64 sites, a pair of single planar microelectrodes delivering bipolar constant current pulses (45-90 microA, 0.1 ms) was applied. Electrophysiological recordings were measured using the 64-channel multielectrode dish. RESULTS: The amplitude of field potential in the rat CA1 region was inhibited by both bupivacaine and ropivacaine. The inhibitory effects of bupivacaine and ropivacaine on field potential amplitudes in CA1 were similar. For bupivacaine 10 microg ml(-1), inhibited field potentials were incompletely recovered; in contrast, for 10 ropivacaine microg ml(-1), inhibited field potentials were completely recovered after washing out with incubation solution. CONCLUSIONS: Inhibitory effects of bupivacaine and ropivacaine on hippocampal field potential amplitude and recovery rate after washout after bupivacaine or ropivacaine treatment represent the underlying mechanisms of the systemic toxicity of local anaesthetics.

Laryngeal exposure during laryngoscopy is better in the 25 degrees back-up position than in the supine position.

BACKGROUND: Good visualization of the glottis is important for tracheal intubation. This study evaluated whether the 25 degrees back-up position improves the quality of the laryngeal view during laryngoscopy. METHODS: Laryngoscopy with a curved blade was performed on 40 anaesthetized patients. The patients were randomly assigned to two groups. Laryngeal views were captured with a rigid 0 degrees endoscope. Views were recorded for each patient in Group A (n = 20) during laryngoscopies performed with the patient lying first in the supine position and then in the 25 degrees back-up position. Laryngeal views for patients in Group B (n = 20) were first captured while the patient was in the 25 degrees back-up position and then while the patient was in the flat supine position. An anaesthetist blinded to the position graded the quality of the images using the percentage of glottic opening (POGO) score. RESULTS: Comparing the two positions, mean (sd) POGO scores increased significantly from 42.2 (27.4)% in supine position to 66.8 (27.6)% in 25 degrees back-up position (P < 0.0001). CONCLUSIONS: During laryngoscopy, the laryngeal view, as assessed by POGO scores, improves significantly in the 25 degrees back-up position when compared with the flat supine position.

A subpopulation of dorsal raphe nucleus neurons retrogradely labeled with cholera toxin-B injected into the inner ear.

Previous studies have shown that: (1) raphe neurons respond to acoustic and vestibular stimuli, some with a latency of 10-15 ms; (2) alterations of the raphe nuclei alter the acoustic startle reflex; (3) the dorsal raphe nucleus (DRN) is the major source of serotonergic neurons; and (4) approximately 57% of the DRN neurons are nonserotonergic. In the present study, cholera toxin subunit-B (CTB) was injected into cat cochleas, and the brain tissue was examined after a survival period of 5-7 days. Aside from neurons which were known to project to the inner ear, i.e., olivocochlear and vestibular efferent neurons, a surprising new finding was made that somata of a subpopulation of DRN neurons were intensely labeled with CTB. These CTB-labeled neurons were densely distributed in a dorsomedian part of the DRN with some in a surrounding area outside the DRN. The present results suggest that a novel raphe-labyrinthine projection may exist. A future study of anterograde labeling with injections of a tracer in the DRN will be needed to establish the existence of a raphe-labyrinthine projection more thoroughly. A raphe-labyrinthine descending input, together with an ascending input from the inner ear to the DRN through intervening neurons, such as the juxta-acousticofloccular raphe neurons (JAFRNs) described by Ye and Kim, may mediate a brain stem reflex whereby a salient multisensory (including auditory and vestibular) stimulus may alter the sensitivity of the inner ear. As a mammal responds to a biologically important auditory-vestibular multisensory event, the raphe projections to the inner ear and other auditory and vestibular structures may enhance the mammal's ability to localize and recognize the sound and respond properly. The raphe-labyrinthine projection may also modulate the inner ear's sensitivity as a function of the sleep-wake arousal state of an organism on a slower time course.

Organization of olivocochlear neurons in the cat studied with the retrograde tracer cholera toxin-B.

We employed cholera toxin-B (CTB), an efficient retrograde tracer, to examine olivocochlear (OC) neurons in the cat. Our primary goals were (1). to determine whether the cat has two types of lateral OC (LOC) neurons as is found in certain rodents and (2). to document the morphology, number, and caudorostral distribution of OC neurons, bilaterally. Adult cats received injections of CTB through the round window of the left cochlea, and, after 3-6 days, the brains were sectioned transversely and CTB was revealed immunocytochemically in every section. In three cats, OC neurons were mapped, counted differentially according to cell group, and the numbers of each plotted bilaterally from caudal to rostral. In one cat, measurements were made on labeled LOC and medial OC (MOC) neurons. The results indicate that LOC neurons can be divided into two groups based on their proximity to the lateral superior olive (LSO): a more populous group of small neurons that have intimate contact with the LSO, designated marginal-LOC neurons, and a less populous, morphologically heterogeneous group, lying more distantly from the LSO, designated para-LOC neurons. Para-LOC neurons lying dorsal and rostral to LSO were significantly larger than marginal-LOC. We hypothesize that the cat marginal-LOC neurons and most probably the larger para-LOC neurons correspond to rodent intrinsic and shell LOC neurons, respectively, which have focal versus diffuse projections beneath the inner hair cells. Concerning MOC neurons, we confirm and extend previous observations on the clustering of these neurons near the rostral tip of the medial superior olivary nucleus and also show that MOC neurons differ in size according to cell group. Finally, we compare the present counts of OC neurons (mean total 1607, consisting of 1058 LOC neurons and 549 MOC neurons innervating one cochlea) and their proportional distribution ipsilaterally and contralaterally with those reported previously. Our estimate of the number of LOC neurons is somewhat higher than those previously obtained either by retrograde labeling with horseradish peroxidase or by counting unmyelinated axons in the olivocochlear bundle. In contrast, our estimate of the number of MOC neurons is very similar to those previously reported.

Adaptation of distortion product otoacoustic emission in humans.

Previous studies of animals observed a phenomenon of adaptation of distortion product otoacoustic emission (DPOAE) and found that the phenomenon was mediated to a large extent by the medial olivocochlear (MOC) reflex. The present study investigated DPOAE adaptation in humans. The following stimuli were used: f2/f1 = 1.2; f2 = 2, 4, or 5.65 kHz; L2 = 50-65 dB SPL re 20 microPa rms, L1 - L2 = 0-15 dB, where L1 and L2 represent levels of the f1 and f2 tones, respectively; duration of two-tone burst = 5.5 s; interburst gap = 20 or 30 s; number of repetitions = 40 or 64. We analyzed the 2f1 - f2 DPOAE as a function of time using a method of heterodyne envelope detection. The subjects were 20 humans aged from 15 to 54 years (median = 21 years) with normal hearing. We observed that (1) humans exhibited DPOAE adaptation phenomenon; (2) the time course of DPOAE level was characterized by a 2-exponential function; (3) distributions of the fast and slow time constants were well separated with their median values being 69 ms and 1.51 s, respectively; (4) distributions of the magnitudes of the fast and slow adaptation components were largely overlapped with their median values being 0.65 and 0.40 dB, respectively; and (5) the combined magnitude of the adaptation ranged from 0.4 to 3.0 dB with a median of 1.10 dB. To our knowledge, the present study is the first published article to describe adaptation of DPOAE in humans. These results should help advance the basic knowledge of human cochlear mechanics operating under the control of the MOC feedback system and contribute to the development of practical applications such as identifying people at high risk of acoustical injury and a clinical test of the functional status of the MOC system.

Connections between the dorsal raphe nucleus and a hindbrain region consisting of the cochlear nucleus and neighboring structures.

Previous studies have shown that neurons in the raphe nuclei respond to acoustic stimuli. The present study investigated connections between the dorsal raphe nucleus (DRN) and a hindbrain region consisting of the cochlear nucleus (CN) and neighboring structures. A mixture of one or more tracers (cholera toxin B, biotinylated dextran amine (BDA), and 3H-leucine) was injected into the cat DRN. Retrograde-labeling results are presented whereby a new structure, to be called the juxta-acoustico-floccular fascicle (JAFF), is identified. The JAFF is surrounded by the CN, flocculus, lateral cerebellar nucleus, lateral vestibular nucleus, and restiform body. The JAFF is closely associated with the infracerebellar nucleus (ICN). Labeled neurons projecting to the DRN were concentrated in the JAFF, embedded among axons. Less numerous labeled neurons were in the ICN and CN. Anterograde-labeling results are presented showing fibers labeled with BDA or with BDA and 3H-leucine in the CN, cochlear nerve and vestibular nerve, indicating that the DRN projects to these structures. The ascending and descending connections between the DRN and the above hindbrain region may mediate a reflex that may alter the sensitivity of the auditory system in response to biologically salient (e.g. threatening or attractive) stimuli.

Purkinje cell degeneration and control mice: responses of single units in the dorsal cochlear nucleus and the acoustic startle response.

The cartwheel cell is the most numerous inhibitory interneuron of the dorsal cochlear nucleus (DCN). It is expected to be an important determinant of DCN function. To assess the contribution of the cartwheel cell, we examined the discharge characteristics of DCN neurons and behavioral measures in the Purkinje cell degeneration (pcd) mice, which lack cartwheel cells, and compared them to those of the control mice. Distortion product otoacoustic emissions and auditory brainstem-evoked response thresholds were similar between the two groups. Extracellularly recorded DCN single units in ketamine/xylazine-anesthetized mice were classified according to post-stimulus time histogram (PSTH) and excitatory-inhibitory response area (EI-area) schemes. PSTHs recorded in mouse DCN included chopper, pauser/buildup, onset, inhibited and nondescript types. EI-areas recorded included Types I, II, III, I/III, IV and V. There were no significant differences in the proportions of various unit types between the pcd and control mice. The pcd units had slightly lower thresholds to characteristic frequency tones; however, they had spontaneous rates, thresholds to noise, and maximum driven rates to noise that were similar to those of the control units. Pcd mice had smaller startle amplitudes, but startle latency, prepulse inhibition/augmentation and facilitation by a background tone were comparable between the two groups. From these results, we conclude that DCN function in response to relatively simple acoustic stimuli is minimally affected by the absence of the cartwheel cells. Future studies employing more complex and/or multimodal stimuli should help assess the role of the cartwheel cells.

Virtual anatomy and movement of lower extremities using virtual reality modeling language.

In medical imaging, the use of three-dimensional image is increasing for both educational and diagnostic purposes. With the advent of techniques for browsing a three-dimensional object, it became possible to display three-dimensional images on a personal computer via the Internet. This report describes the construction of a three-dimensional virtual model of human lower extremities that was linked with the data acquired from gait analysis in order to perform three-dimensional gait analysis.

Projection of the marginal shell of the anteroventral cochlear nucleus to olivocochlear neurons in the cat.

The marginal shell of the anteroventral cochlear nucleus is anatomically and physiologically different from its central core. Previous studies suggest that neurons in the marginal shell are well suited to encode the intensity of acoustic stimuli. To investigate the projections of the marginal shell, a focal injection (<100 nl) of a mixture of biotinylated dextran amine (BDA) and (3)H-leucine was made into the marginal shell of the cat combined with injection of cholera toxin subunit-B (CTB) into the cochleas. Following a 7-day survival, the cats were perfused. Axons and swellings labeled with BDA and olivocochlear neurons labeled with CTB were immunocytochemically stained black and brown, respectively. (3)H-leucine labels were visualized by autoradiography. Labeled neural structures were examined via light microscopy. We found that swellings labeled with BDA, sometimes doubly labeled with BDA and (3)H-leucine, were in close apposition with dendrites and/or somata of olivocochlear neurons identified with CTB labeling. Double labeling with BDA and (3)H-leucine signifies that the label was anterogradely transported. The results support the conclusion that the anteroventral cochlear nucleus projects to medial olivocochlear neurons bilaterally and to lateral olivocochlear neurons ipsilaterally. Furthermore, the results are consistent with the interpretation that the marginal shell provides a source of the above-mentioned projections. Together with information in the literature, the present anatomical results support a hypothesis that the marginal shell provides information about stimulus intensity as a part of a reflex (or feedback gain control) system comprising the cochlea, cochlear neurons, cochlear nucleus, medial olivocochlear neurons, and cochlear outer hair cells.

Distortion product otoacoustic emissions in the CBA/J mouse model of presbycusis.

CBA mice do not exhibit age-related loss of auditory sensitivity or cochlear pathology until relatively late in life. Therefore, this strain is believed to be an excellent animal model for the examination of the effects of age on the cochlea. To evaluate the effects of age on outer hair cell function, 2f1-f2 distortion product otoacoustic emissions (DPOAEs) were measured for f2 between 8 and 16 kHz in CBA/J mice between 1 and 25 months of age. CBA mice exhibited mild age-related changes in DPOAE level and detection threshold at 17 months of age, and changes of 20-40 dB by 25 months of age. The DPOAE level decreased and detection threshold increased with age in a frequency-dependent manner, starting at high frequencies and eventually extending to low frequencies. The range of frequencies in which notches were observed in the DPOAE input/output (I/O) functions extended toward lower frequencies by 17 months of age. Notches were absent in the I/O functions of 25-month-old mice. The present results for a frequency range of 8-16 kHz suggest that age has modest effects on outer hair cell function in CBA mice.

Adaptation of 2f1-2f2 distortion product otoacoustic emission in young-adult and old CBA and C57 mice.

The phenomenon of efferent-mediated adaptation of 2f1-f2 distortion product otoacoustic emission (DPOAE) was investigated in two strains (CBA/JNia and C57BL/6JNia) of mice of various ages using stimuli presented monaurally or binaurally. The present study demonstrated the existence of the DPOAE adaptation phenomenon in mice analogous to that previously reported in cats. The present data were fitted with one- or two-exponential functions. With a one-exponential fit in 2-month old mice, the adaptation magnitude ranged from 0 to 4 dB with the average value of 0.5 to 1.6 dB and the average time constant was 0.5 to 2.3 s. With a two-exponential fit, the shorter time constant was 0.3 to 1.7 s. The adaptation magnitude and time constant were similar between the monaural and binaural stimulations. We observed that there was a statistically significant decrease of adaptation magnitude in older CBA mice with age-related hearing loss when compared with young adult mice. The results from the young adult mice should be useful in future studies, e.g., a study of developmental changes in post-natal mice, or changes accompanying an alteration in the central auditory system arising from any etiology. We suggest that this phenomenon can be used as a tool for advancing basic knowledge of the auditory system and for assessing an impairment of the olivocochlear system, e.g., in aging.

Responses of neurons to click-pairs as simulated echoes: auditory nerve to auditory cortex.

When two identical sounds are presented from different locations with a short interval between them, the perception is of a single sound source at the location of the leading sound. This "precedence effect" is an important behavioral phenomenon whose neural basis is being increasingly studied. For this report, neural responses were recorded to paired clicks with varying interstimulus intervals, from several structures of the ascending auditory system in unanesthetized animals. The structures tested were the auditory nerve, anteroventral cochlear nucleus, superior olivary complex, inferior colliculus, and primary auditory cortex. The main finding is a progressive increase in the duration of the suppressive effect of the leading sound (the conditioner) on the response to the lagging sound (the probe). The first major increase occurred between the lower brainstem and inferior colliculus, and the second between the inferior colliculus and auditory cortex. In neurons from the auditory nerve, cochlear nucleus, and superior olivary complex, 50% recovery of the response to the probe occurred, on average, for conditioner and probe intervals of approximately 2 ms. In the inferior colliculus, 50% recovery occurred at an average separation of approximately 7 ms, and in the auditory cortex at approximately 20 ms. Despite these increases in average recovery times, some neurons in every structure showed large responses to the probe within the time window for precedence (approximately 1-4 ms for clicks). This indicates that during the period of the precedence effect, some information about echoes is retained. At the other extreme, for some cortical neurons the conditioner suppressed the probe response for intervals of up to 300 ms. This is in accord with behavioral results that show dominance of the leading sound for an extended period beyond that of the precedence effect. Other transformations as information ascended included an increased variety in the shapes of the recovery functions in structures subsequent to the nerve, and neurons "tuned" to particular conditioner-probe intervals in the auditory cortex. These latter are reminiscent of neurons tuned to echo delay in bats, and may contribute to the perception of the size of the acoustic space.

Responses of anteroventral cochlear nucleus neurons of the unanesthetized decerebrate cat to click pairs as simulated echoes.

To elucidate the contribution of the anteroventral cochlear nucleus (AVCN) to 'echo' processing, this study documents the responses of AVCN neurons to simulated echoes and compares them to those of auditory nerve (AN) fibers. Single unit discharges were recorded from 121 units in the AVCN of 21 unanesthetized decerebrate cats in response to click pairs with inter-click intervals ranging from 1 to 32 ms between 45 and 105 dB SPL re 20 microPa. Units were classified according to the post-stimulus time histogram (PSTH) and excitatory-inhibitory response area (EI-area) schemes. Based on their spontaneous rates (SR), units were subdivided into low- ( < 20 spikes/s) and high- ( > 20 spikes/s) SR groups. A majority of the units exhibited second-click responses whose recovery time courses were similar to those of AN fibers. These units included primary-like, chopper and onset units in the PSTH scheme and Types I, I/III and III units in the EI-area scheme. A minority of the units exhibited responses that were distinct from those of AN fibers, in that they had second-click response recovery times that were either markedly reduced or prolonged. This group of units included those with primary-like, chopper and onset PSTHs and Type I/III and III EI-areas. No significant difference was found in the second-click response among various PSTH or EI-area types. High-SR AVCN units exhibited a decrease in the second-click response with increasing level. In contrast, low-SR AVCN units showed little level-dependent change in the second-click responses. This SR-based difference was similar to that previously found among AN fibers. The present results suggest that, although a majority of AVCN units exhibit similar time courses of second-click response recovery to those of AN fibers, there do exist mechanisms in the cochlear nucleus that can substantially alter this representation. Furthermore, the difference between the second-click response recovery functions of low- and high-SR AVCN units and the consistency of this finding between AVCN and AN suggest that SR represents an important dimension for signal representation in the AVCN neurons.

A new method of measuring distortion product otoacoustic emissions using multiple tone pairs: study of human adults.

OBJECTIVE: To increase the speed of a distortion product otoacoustic emissions (DPOE) test of cochlear function by employing a new multiple-tone-pair method and to validate the method. DESIGN: We used a new method of employing multiple tone pairs in measuring DPOEs proposed by Zurek and Rabinowitz and implemented in a modified Grason-Stadler Model GSI-60. We investigated the applicability of the multiple-pair method by comparing the 2f1-f2 DPOEs obtained with a 3-pair method with the conventional 1-pair results in human adults; f1 and f2 represent two frequencies of each tone pair, f1 < f2, f2/f1 = 1.2. We used two sets of 3-pair stimuli: 1) f2 at 1.5, 3, and 6 kHz; and 2) f2 at 2, 4, and 8 kHz. The 1-pair stimuli had f2 at each of the above six frequencies. The primary tone levels were L1 = 65 and L2 = 50 dB SPL re 20 microPa. RESULTS: We obtained DPOEs from 98 ears with normal hearing and 94 ears with sensorineural hearing loss in 103 human adults. We found: 1) that the DPOE levels obtained with the 3-pair method were strongly correlated with those of the 1-pair method, with correlation coefficients of 0.83 to 0.96; 2) that the mean DPOE level versus frequency functions for the normal ears were similar between the 3-pair and 1-pair methods; a 2-way analysis of variance indicated no significant difference between the two methods; 3) that the mean difference between DPOE levels obtained with the 3-pair and 1-pair methods was small (less than 1.3 dB in 11 of the 12 conditions examined, i.e., six frequencies each for normal ears and hearing-impaired ears) although the differences were significant in 6 of the 12 conditions as determined by the paired t-test; and 4) that the DPOE test performances of distinguishing normal from impaired ears were similar between the 3-pair and 1-pair tests; areas under the receiver operating characteristic curves were not significantly different between the two tests for four of the six frequencies tested as determined by a statistical procedure of Hanley and McNeil; for the remaining two frequencies where the differences were significant, each of the two tests was better than the other at one frequency. CONCLUSIONS: The 3-pair DPOE method yielded results generally in good agreement with those of the conventional 1-pair DPOE method. To our knowledge, this is the first systematic study of a multiple-pair DPOE method. Because a 3-pair method can be conducted approximately two to three times as fast as a 1-pair method, the former is advantageous, particularly for an auditory screening test.