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PubMed2004

Changing motor patterns of the 3rd axillary muscle activities associated with longitudinal control in freely flying hawkmoths.

The 3rd axillary muscles (3AXMs) in the mesothorax in hawkmoths are direct flight muscles and pull forewings back along to the body axis. The 3AXMs are regarded as steering muscles because of their changeable activities during turning flight under tethered conditions. We investigated activities of the upper unit of the 3AXMs during free flight with a micro-telemetry device and captured body and wing movements by high-speed cameras. The 3AXM was activated with 1 to 3 spikes per each wingbeat cycle but sometimes ceased to fire. The phase of the onset of the activities was, even though it was variable, close to the phase of the elevator muscle activities. Therefore the upper unit of the 3AXM activities would affect upstroke properties phasically including wing retractions. We focused on longitudinal flight control and identified a correlation between the phase of the 3AXM and body pitch angle, which is important kinematical parameter for longitudinal control in insect flight. The phasic changes of the 3AXM activities would support quick changes in longitudinal control.

Animals↗

PubMed2005

Fine-scale tracking of marine turtles using GPS-Argos PTTs.

High-accuracy location data of wildlife telemetry using conventional satellite location systems are difficult to obtain. However, such data are necessary to clarify the nature of movements and home range sizes of animals. In order to measure the high-accuracy location data, we developed new GPS-Argos Platform Terminal Transmitters (PTTs) which transmit both the conventional location and GPS location simultaneously. Two experiments, one in an artificial rearing pond and the other in the open sea, were performed. First, two hawksbill turtles were tracked with the PTTs in a 5 ha breeding pond in Thailand. Their home ranges using both data were calculated and found to be 2.96 ha and 0.93 ha by the GPS data, and 156,740 ha and 184,478 ha by a conventional data. Secondly, a female green turtle attached with the GPS-Argos was released from the coast of Pangnga Province, Thailand. There was a relationship between depth and speed of travel based on the GPS data. The data from the PTT showed that the turtle moved south along the coastline at the depth of less than 20 m for 5 days, and then stayed at a depth of less than 10 m for 4 days. However, we could not find any clear relationship using conventional data. Only a meandering movement at a variety of depths was observed. The results of the two experiments indicated the PTTs have an enormous potential for enhancing our understanding of fine-scale movement patterns and home ranges of marine turtles.

Animals↗

PubMed2006

Pacing and sensing disturbances in patients with DDD pacemakers in the early period after implantation.

OBJECTIVES: We sought to determine the usefulness of ambulatory 24-hour Holter monitoring in detecting asymptomatic pacemaker (PM) malfunction episodes in patients with dual-chamber pacemakers whose pacing and sensing parameters were proper, as seen in routine post-implantation follow-ups. This aspect has not been widely discussed so far. METHODS AND RESULTS: Ambulatory 24-hour Holter recordings [HM] were performed in 100 patients with DDD pacemakers one day after the implantation. Only asymptomatic patients with proper pacing and sensing parameters (assessed on PM telemetry on the first day post-implantation) were enrolled in the study. The following parameters were assessed: failure to pace, failure to sense (both oversensing and undersensing episodes) as well as the percentage of all PM disturbances. Despite proper sensing and pacing parameters, HM revealed PM disturbances in 23% of the patients.Atrial undersensing episodes were found in 12 patients and failure to capture in I patient. T wave oversensing was the most common ventricular channel disorder (9 patients). Malfunction episodes occurred sporadically, leading to pauses of up to 1.6 s or temporary bradycardia, which were, nevertheless, not accompanied by clinical symptoms. No ventricular pacing disturbances were found. CONCLUSION: Asymptomatic pacemaker dysfunction may be observed in nearly 25% of patients with proper DDD parameters after implantation.Thus, ambulatory HM during the early post-implantation period may be a useful tool to detect the need to reprogramme PM parameters.

Aged↗

PubMed1978

pH-tested reflux without hiatus hernia.

Gastroesophageal reflux was tested for with a pH telemetry capsule. In 29 individuals in whom no hiatus hernia was demonstrated on barium esophagram, the transverse diameter of the intrahiatal esophagus was compared to that of the intrathoracic. When the width of the intrahiatal esophagus was two-thirds or less that of the intrathoracic, pH-proven reflux was an infrequent event. When wider, reflux occurred with high frequency.

Gastric Acidity Determination↗

PubMed2000

Effects of clomipramine hydrochloride on heart rate and rhythm in healthy dogs.

OBJECTIVE: To determine the effects of clomipramine hydrochloride on heart rate and rhythm in dogs. ANIMALS: 17 healthy Beagles. PROCEDURES: In experiment 1, 8 dogs received placebo or clomipramine (20 mg/kg of body weight, q 24 h, PO) for 7 days in a 2-way crossover design. In experiment 2, 9 dogs were evaluated for 48 hours before and 24 hours after oral administration of clomipramine (4 or 12 mg/kg) in a 2-way crossover design. Electrocardiogram and heart rate were monitored continuously by use of telemetry. RESULTS: A significant diurnal rhythm in heart rate was detected; minimum values were recorded at night. Administration of 20 mg of clomipramine/kg induced a significant reduction in heart rate, with peak effect achieved approximately 12 hours after dosing. Administration of 4 or 12 mg of clomipramine/kg did not result in significant changes in heart rate. Sinoatrial and second-degree atrioventricular block and ventricular escape beats were observed during periods of slow heart rate in more dogs that received clomipramine (3 to 4 of 8 dogs), compared with dogs that received placebo (1 to 2 of 8 dogs), but this difference was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Short-term administration of clomipramine induced benign cardiovascular effects in dogs rather than the potentially dangerous arrhythmias or tachycardia reported following administration of tricyclic antidepressants to humans. Precautions regarding cardiovascular effects may not be needed for the use of clomipramine in healthy dogs.

Animals↗

PubMed2000

Use of an instrument sandwiched between the hoof and shoe to measure vertical ground reaction forces and three-dimensional acceleration at the walk, trot, and canter in horses.

OBJECTIVE: To develop an instrument that could be sandwiched between the hoof and shoe of horses and that would reliably measure vertical ground reaction forces and three-dimensional acceleration at the walk, trot, and canter. ANIMALS: 5 clinically sound Thoroughbreds. PROCEDURES: The recording instrument (weight, 350 g) consisted of 2 metal plates, 2 bolts, 4 load cells, and 3 accelerometers. It was mounted to the hoof with a glue-on shoe and devised to support as much load exerted by a limb as possible. The load cells and accelerometers were wired to a 16-channel transmitter, and transmitted signals were received and amplified with a telemetry receiver. RESULTS: The recording instrument could measure in real time the 4 components of the ground reaction force or their resultant force along with acceleration in 3 dimensions as horses walked, trotted, or cantered on a treadmill. Patterns of force-time curves recorded for consecutive strides were similar to each other and to those previously reported, using a force plate. CONCLUSIONS AND CLINICAL RELEVANCE: The recording instrument developed for use in the present study allowed us to record vertical ground reaction force and acceleration in 3 dimensions in horses at the walk, trot, and canter.

Acceleration↗

PubMed1990

Intensive neurodiagnostic monitoring in psychiatry.

A series of technological advances have made it possible to closely monitor electrophysiological and behavioural manifestations of episodic clinical events over prolonged periods of time, with the ability to review the records at leisure or to submit them to computer analysis. The more promising techniques are time-locked video/EEG monitoring, cable telemetry, radiotelemetry, ambulatory cassette recording, intensive plasma anti-epileptic drug monitoring and continuous neuropsychological monitoring. The greatest promise of these techniques is for the diagnosis, research and management of epilepsy. For psychiatry, they offer additional help in the differential diagnosis of non-epileptic events from epilepsy, the most important of which are psychogenic seizures and episodes of aggression. This paper discusses the potential role of these techniques in the assessment of non-epileptic events and transient cognitive impairment in clinical psychiatry.

Anticonvulsants↗

PubMedDate not supplied

Comparison of speech recognition with different speech coding strategies (SPEAK, CIS, and ACE) and their relationship to telemetric measures of compound action potentials in the nucleus CI 24M cochlear implant system.

Speech understanding and subjective preference for three different speech coding strategies (spectral peak coding [SPEAK], continuous interleaved sampling [CIS], and advanced combination encoders [ACE]) were investigated in 11 post-lingually deaf adult subjects, using the Nucleus CI 24M cochlear implant system. Subjects were randomly assigned to two groups in a balanced crossover study design. The first group was initially fitted with SPEAK and the second group with CIS. The remaining strategies were tested sequentially over 8 to 10 weeks with systematic variations of number of channels and rate of stimulation. Following a further interval of 3 months, during which subjects were allowed to listen with their preferred strategy, they were tested again with all three strategies. Compound action potentials (CAPs) were recorded using neural response telemetry. Input/output functions in relation to increasing stimulus levels and inter-stimulus intervals between masker and probe were established to assess the physiological status of the cochlear nerve. Objective results and subjective rating showed significant differences in favour of the ACE strategy. Ten of the 11 subjects preferred the ACE strategy at the end of the study. The estimate of the refractory period based on the inter-stimulus interval correlated significantly with the overall performance with all three strategies, but CAP measures could not be related to individual preference of strategy or differences in performance between strategies. Based on these results, the ACE strategy can be recommended as an initial choice specifically for the Nucleus CI 24M cochlear implant system. Nevertheless, access to the other strategies may help to increase performance in individual patients.

Acoustic Stimulation↗

PubMed1978

Assessment of orthoses by means of speed and heart rate.

Energy expenditure is an important parameter in the assessment of gait and orthotic treatment of heavily handicapped patients, since any orthosis which increases the effort required is likely to be discarded with consequently disturbing implications. Heart rate has been shown to be a reliable monitor of energy expenditure and is convenient because ECG can be telemetered by a miniature radio transmitter. Using a transmitter causes minimal interference with the patient, but care must be employed to obtain ECG signals free of artefact from subjects who are exercising. Means of reducing artefact are discussed, as are ways in which heart rate monitoring by radio telemetry is being used in the routine assessment of orthotic treatment of paediatric patients and the development of new orthotic devices.

Child↗

PubMed1997

Analysis of telemetric time series data for periodic components using DQ-FIT.

DQ-FIT and CV-SORT have been developed to facilitate the automatic analysis of data sampled by radiotelemetry, but they can also be used with other data sampled in chronobiological settings. After import of data, DQ-FIT performs conventional linear, as well as rhythm analysis according to user-defined specifications. Linear analysis includes calculation of mean values, load values (percentage of values above a defined limit), highest and lowest readings, and areas under the (parameter-time) curve (AUC). All of these parameters are calculated for the total sampling interval and for user-defined day and night periods. Rhythm analysis is performed by fitting of partial Fourier series with up to six harmonics. The contribution of each harmonic to the overall variation of data is tested statistically; only those components are included in the best-fit function that contribute significantly. Parameters calculated in DQ-FIT's rhythm analysis include mesor, amplitudes, and acrophases of all rhythmic components; significance and percentage rhythm of the combined best fit; maximum and minimum of the fitted curve and times of their occurrence. In addition, DQ-FIT uses the first derivative of the fitted curve (i.e., its slope) to determine the time and extent of maximal increases and decreases within the total sampling interval or user-defined intervals of interest, such as the times of lights on or off. CV-SORT can be used to create tables or graphs from groups of data sets analyzed by DQ-FIT. Graphs are created in CV-SORT by calculation of group mean profiles from individual best-fit curves rather than their curve parameters. This approach allows the user to combine data sets that differ in the number and/or period length of harmonics included. In conclusion, DQ-FIT and CV-SORT can be helpful in the analysis of time-dependent data sampled by telemetry or other monitoring systems. The software can be obtained on request by every interested researcher.

Animals↗

PubMed1996

Role of angiotensin II in reflex tachycardia during hypotension caused by a calcium channel blocker.

Blood pressure and heart rate were measured by telemetry in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) to investigate the contribution of angiotensin II to the reflex tachycardia resulting from exaggerated hypotension caused by a high dose of a calcium channel blocker. Pre-treatment with TCV-116, an angiotensin II AT1 receptor antagonist, or enalapril partially attenuated the reflex tachycardia induced by manidipine, but TCV-116 had almost no effect on the sinus tachycardia induced by isoproterenol. The suppressive effects of TCV-116 against the reflex tachycardia tended to be more obvious in WKY than in SHR, though the difference was not statistically significant. Concurrent administration of propranolol almost completely inhibited both the reflex tachycardia and the sinus tachycardia in SHR and WKY, indicating that the sympathetic nervous system contributes to both types of tachycardia. We demonstrated that angiotensin II may be involved in the reflex tachycardia induced by calcium channel blockers probably via activation of some component of the sympathetic nervous system other than postsynaptic factors at the sinus node.

Angiotensin II↗

PubMed1994

Influence of perflubron emulsion particle size on blood half-life and febrile response in rats.

Perfluorochemical (PFC) emulsions are particulate in nature and, as such, can cause delayed febrile reactions when injected intravenously. This study investigated the influence of emulsion particle size on intravascular retention and on body temperature changes in unrestrained conscious rats. Concentrated (60% to 90% w/v) emulsions based on perflubron (perfluorooctyl bromide [PFOB]) with mean particle sizes ranging from 0.05 microns to 0.63 microns were tested. Rats were fitted with a chronic jugular catheter and an abdominal body temperature telemetry unit. Fully recovered, conscious rats were monitored for 24 hours after infusion (dose = 2.7 g PFC/kg). Emulsion blood half-life (T1/2) was determined from blood perflubron levels measured by gas chromatography. Emulsions with a particle size of 0.2-0.3 microns caused fevers (6 to 8 hour duration) which peaked at 1-1.5 degrees C above normal (approximately 37.5 degrees C). Fevers could be blocked by i.v. treatment with either cyclooxygenase inhibitors (ibuprofen) or corticosteroids (dexamethasone). Both intensity and duration of the temperature response, quantified by area under the temperature curve, was decreased significantly for emulsions with a particle size < or = 0.12 micron. Blood T1/2 varied inversely with particle size, and was 3 to 4 fold longer for emulsions with a mean particle size < or = 0.2 micron. Thus, smaller emulsion particles more effectively evaded the reticuloendothelial system, which resulted in longer intravascular retention, less macrophage activity, and reduced febrile responses.

Animals↗

PubMed1997

Chronic interstitial infusion of protein to primate brain: determination of drug distribution and clearance with single-photon emission computerized tomography imaging.

High-flow interstitial infusion into the brain, which uses bulk fluid flow to achieve a relatively homogeneous drug distribution in the extracellular space of the brain, has the potential to perfuse large volumes of brain. The authors report reproducible long-term delivery of 111In-diethylenetriamine pentaacetic acid-apotransferrin (111In-DTPA-Tf) (molecular mass 81 kD) to Macaca mulatta brain and monitoring with single-photon emission computerized tomography (SPECT). The 111In-DTPA-Tf was infused at 1.9 microl/minute over 87 hours into the frontal portion of the centrum semiovale using a telemetry-controlled, fully implanted pump. On Days 1, 3, 4, 8, 11, and 15 after beginning the infusion, planar and SPECT scans of 111In-DTPA-Tf were obtained. Spread of protein in the brain ranged from 2 to 3 cm and infusion volumes ranged from 3.9 to 6.7 cm3. Perfusion of over one-third of the white matter of the infused hemisphere was achieved. From brain SPECT images of (99m)Tc-hexamethylpropyleneamine oxime, which was administered intravenously before each 111In scan, the authors also found that blood perfusion in the infused region was reduced by less than 5% relative to corresponding noninfused regions. Histological examination at 30 days revealed only mild gliosis limited to the area immediately surrounding the needle tract. These findings indicate that long-term interstitial brain infusion is effective for the delivery of drugs on a multicentimeter scale in the primate brain. The results also indicate that it should be possible to perfuse targeted regions of the brain for extended intervals to investigate the potential utility of neurotrophic factors, antitumor agents, and other materials for the treatment of central nervous system disorders.

Animals↗

PubMed2000

Long-term testing of an intracranial pressure monitoring device.

OBJECT: Long-term monitoring of intracranial pressure (ICP) is limited by the lack of an implantable sensor with low drift. The goal of this study was to demonstrate that a new capacitive transducer system will produce accurate and stable ICP records over extended periods. METHODS: Intracranial pressure sensors were implanted into the frontal white matter of four dogs. In addition, a fluid-filled catheter was placed in the cisterna magna (CM) to measure cerebrospinal fluid (CSF) pressure. The animals were tested using standard physiological maneuvers such as jugular vein compression, head elevation, and CSF withdrawal from and saline injection into the CM to verify that the ICP sensor precisely matched CSF pressure changes. The mean ICP pressure and CM pressure were compared for months to demonstrate that the transducer system produced minimal drift over time. The change in the ICP sensor record closely duplicated that of the CSF waveform in the CM in response to well-known physiological stimuli. More important, mean ICP pressure remained within 3 mm Hg of CM pressure for months, with a mean difference of less than 0.3 mm Hg. Histological examination of the dog brains revealed only minimal tissue reaction to the presence of the sensor. CONCLUSIONS: The authors demonstrate a new implantable solid-state sensor that reliably measures ICP for months, with minimal drift. The clinical application of this sensor and its telemetry is for long-term monitoring of patients with head injury, mass lesions, and hydrocephalus.

Animals↗

PubMed2003

Evaluation of living conditions of free-ranging animals by automated chronobiological analysis of behavior.

A biorhythmical method has been developed to assess behavior patterns and to evaluate the living conditions of animals that can be applied also to humans. All kinds of continuous and equidistant long-term recordings of behavior are suitable for this method. Time functions from an automatic telemetry system (ETHOSYS II) were analyzed macroscopically (comparison of daily levels) and microscopically (autocorrelation function and power spectral analysis). Degrees of functional coupling (DFCs) were calculated to identify and evaluate disturbances in behavior. Hierarchic frequency tuning of complex rhythmic functions of behaviors, leads primarily to period lengths that are synchronized with the 24-h period. DFCs, a measure of harmony between internal rhythms and the external 24-h period, were found to be high in well-adapted, healthy, and undisturbed individuals but were lowered during periods of adaptation, sickness, or social interaction. Specific stress conditions could be identified and evaluated in several species, under various conditions, using these biorhythmic analyses.

Animal Migration↗

PubMed1984

Motivation as a factor of perceived exertion in purposeful versus nonpurposeful activity.

Perceived exertion during the performance of purposeful and nonpurposeful activity was studied in 26 women. The subjects acted as their own controls in the performance of both kinds of exercise. The two exercises were jumping rope, defined as a purposeful activity, and jumping in place without a rope, defined as a nonpurposeful activity. In each activity the subjects exercised to reach the subjective point of "very hard work" on the Borg Scale of Perceived Exertion. Duration and cessation of exercise were entirely controlled by the performers. Heart rate responses during and immediately after cessation of exercise, measured by electrocardiographic telemetry, and duration of exercise in seconds were compared for the two types of exercise. Results showed that heart rate increase at a given rate of perceived exertion was significantly higher (.001) for jumping rope. This raises the possibility that workload was inadvertently perceived by the performers to be greater in nonpurposeful activity and provides support for the hypothesis that purposeful activity serves as an intrinsic motivator to the performer.

Adult↗

PubMed1982

Recent developments in the diagnosis and therapy of epilepsy.

Recent advances in the diagnosis of epilepsy include the development of a clinically useful classification of epileptic seizures and the recognition of specific epileptic disorders. These advances have been aided by the advent of x-ray computed tomography, long-term electroencephalographic telemetry, and video monitoring. Techniques for functional imaging of the human brain promise even greater diagnostic capabilities. New antiepileptic drugs have improved medical management, and technical and theoretical advances in pharmacokinetics have permitted physicians to design balanced dosing for individual patients. Although currently underused, surgical treatment of partial complex epilepsy can be safe and effective when used appropriately. Operant conditioning of electroencephalography may become another practical alternative therapy. Contributions of basic research to understanding the complications of status epilepticus have influenced treatment protocols and greatly improved the prognosis of this potentially lethal condition.

Anticonvulsants↗

PubMed1980

Serologic and hematologic values of wild coyotes in Wisconsin.

Blood samples were obtained from 30 coyotes (Canis latrans) captured in northern Wisconsin in conjunction with radio-telemetry studies. Samples were assayed for seven hematologic values, seven serum chemistries, serum albumin, globulin and total protein. Results are given with respect to sex and age and are compared with available data for captive wild and pen-raised coyotes. Leukocyte counts were greater for males than females and packed cell volumes were greater for adults than young, possibly due to differential response to capture and handling stress. Hemoglobin concentrations and calcium levels suggest differences in nutrition between pen-raised and wild coyotes. Sex and age differences in serum calcium for wild coyotes probably reflect nutritional differences between groups examined. Juvenile coyote serum alkaline phosphatase levels declined curvilinearly with age for coyotes less than one year old, suggesting a possible technique for separating juveniles and yearlings captured in autumn that are released for research purposes. Elevated glucose levels and leukocyte counts in wild coyotes may reflect greater handling stress than for pen-raised and captive coyotes. No significant sex or age effects were found for levels of serum urea nitrogen, total protein, cholesterol, and total bilirubin.

Age Factors↗