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PubMed1976

Psychological factors and clinical observations in acupuncture analgesia and pain abatement.

The present study attempted to (a) replicate findings on acupuncture reported in the Chinese literature; (b) investigate the effects of acupuncture in achieving analgesia and pain abatement; and (c) isolate the relevant psychological and/or physiological variables involved. Fifty volunteer men and women between 18 and 30 years of age were administered the acupuncture phase of this study for induction of analgesia and relief of pain in the oral cavity. A comparable group of 30 additional Ss were included in the study for comparison with the acupuncture group on several objective psychological measures. Forty of the acupuncture Ss were classified as totally successful. No significant differences between the acupuncture group and the comparable control group were obtained on the objective psychological measures, including measures of personality, suggestibility, anxiety, and attitudes. The results appear to indicate that psychological factors are minimally involved in obtaining analgesia and pain abatement with acupuncture techniques. Several interesting clinical observations were noted during the acupuncture procedure, including absence of discernable signs of analgesia, consistency of results, contralateral analgesic effect related to the location of acupuncture needles, etc. These results were discussed in terms of the possible role of physiological and psychological factors in acupuncture. Possible areas of future research were also discussed.

Acupuncture Therapy↗

PubMed1994

Influence of alkaloid concentration of tall fescue straw on the nutrition, physiology, and subsequent performance of beef steers.

Two experiments were conducted to evaluate digestion, performance, and physiological responses to Acremonium coenophialum-infected tall fescue straw offered to vary ergovaline concentrations. In Exp. 1, 16 Hereford x Angus ruminally cannulated steers (370 +/- 12 kg BW, mean +/- SE) were blocked by age and BW and, within block, randomly assigned to one of four treatments containing graded concentrations of ergovaline in the diet: 1) 0 ppb, 2) 158 ppb, 3) 317 ppb, and 4) 475 ppb. Alkaloid concentrations were produced using various mixtures of two varieties of tall fescue straw that had similar genetic and phenotypic characteristics but differed in degree of endophyte incidence and associated concentrations of alkaloids. In the 36-d digestion study, feed intake, apparent DMD, and total tract NDF digestion were not influenced by alkaloid concentration (P > .10). Differences were observed with digesta kinetics; specifically indigestible ADF (IADF) fill and outflow decreased linearly with increasing alkaloid concentration (P < .10). These differences, however, may be attributed to differences in IADF concentration of the diets. Physiological variables (heart rates, respiration rates, and rectal, ear, and tailhead skin surface temperatures) were not influenced by alkaloid concentration (P > .10). Concentration of serum prolactin measured weekly tended (P < .10) to decrease with increasing alkaloid concentration of the diet. At the conclusion of the study, each steer was injected with 100 micrograms of thyrotropin-releasing hormone (TRH). All steers responded to the TRH challenge (P < .10); however, responses did not differ (P > .10) between alkaloid concentrations of the basal diet (P > .10).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Nutritional Physiological Phenomena↗

PubMed1990

SCSB method compared to EEG-based polygraphy in sleep state scoring of newborn infants.

Knowledge of the sleep state is important in physiological studies since many physiological variables show different properties in different sleep states. The recently developed static charge sensitive bed (SCSB) method allows long-term recordings of body movements, respiration and ballistocardiogram without electrodes attached to the subject. The recordings are easy to carry out and they do not disturb the subject in any way. The recorded variables are basic characteristics of different sleep states. SCSB-recordings and electroencephalography (EEG) based polygraphy as well as blind sleep state scoring were carried out in 8 newborn infants. The positive correlation between SCSB-scoring and EEG-based polygraphy scored by two clinical neurophysiologists was 68.1 and 64.1%. Only in 2% of all epochs was active sleep scored as quiet sleep or vice versa. The results indicate the usefulness of the SCSB method in sleep state scoring of newborn infants.

Ballistocardiography↗

PubMed1987

Cerebral circulation, metabolism, and blood-brain barrier of rats in hypocapnic hypoxia.

The effects of hypoxic hypoxia on physiological variables, cerebral circulation, cerebral metabolism, and blood-brain barrier were investigated in conscious, spontaneously breathing rats by exposing them to an atmosphere containing 7% O2. Hypoxia affected a marked hypotension, hypocapnia, and alkalosis. Cortical tissue high-energy phosphates and glucose content were not affected by hypoxia, glucose 6-phosphate, lactate, and pyruvate levels were significantly increased. Blood-brain barrier permeability, regional brain glucose content and lumped constant were not changed by hypoxia. Local cerebral glucose utilization (LCGU) rose by 40-70% of control values in gray matter and by 80-90% in white matter. Under hypoxia, columns of increased and decreased LCGU were detectable in cortical gray matter. Local cerebral blood flow (LCBF) increased by 50-90% in gray matter and by up to 180% in white matter. Coupling between LCGU and LCBF in hypoxia remained unchanged. The data suggest a stimulation of glycolysis, increased glucose transport into the cell, and increased hexokinase activity. The physiological response of gray and white matter to hypoxia obviously differs. Uncoupling of the relation between LCGU and LCBF does not occur.

Aminoisobutyric Acids↗

PubMed2005

Factors that influence use of a home cardiorespiratory monitor for infants: the collaborative home infant monitoring evaluation.

BACKGROUND: As part of the Collaborative Home Infant Monitoring Evaluation, a home monitor was developed to record breathing, heart rate, other physiologic variables, and the time the monitor was used. OBJECTIVE: To determine the frequency of monitor use, factors that influence use, and validity of a model developed to predict use. DESIGN: We developed a model to predict monitor use using multiple linear regression analysis; we then tested the validity of this model to predict adherence for the first week of monitoring and for the subsequent 4-week period (weeks 2-5). SETTING: Clinical research centers in Chicago, Ill; Cleveland, Ohio; Honolulu, Hawaii; Los Angeles, Calif; and Toledo, Ohio. Patients Preterm infants, infants younger than 1 month with a history of autopsy-confirmed sudden infant death syndrome in a sibling, and infants with an idiopathic apparent life-threatening event were divided into 2 cohorts based on enrollment date. Main Outcome Measure Mean hours of monitor use per week. RESULTS: In cohort 1, the variables available before monitoring were only weakly associated with total hours of monitor use in weeks 2 to 5 (total model r(2) = 0.08). However, when hours of monitor use in week 1 were included as a variable to predict monitor use in weeks 2 to 5, the r(2) increased to 0.64 for hours of monitor use per week. CONCLUSIONS: Our data show that monitor use in the first week was the most important variable for predicting subsequent monitor use. The study suggests that a major focus of home monitoring should be adherence in the first week, although it remains to be tested whether this adherence can be altered.

Adolescent↗

PubMed1989

Identification of high-risk situations in a behavioral weight loss program: application of the relapse prevention model.

The relapse prevention model has recently been applied to the treatment of obesity in order to explain why people stop practising caloric restriction and hence stop losing weight. This study attempted to identify environmental, affective and physiological variables characterizing 'high risk' situations that lead individuals to either overeat or eat unplanned meals, thereby violating the rules of dietary abstinence. Thirty-five individuals (5 male; 30 female) at least 20 percent above ideal body weight were instructed to keep a continuous record of their eating behavior during a 10-week behavioral weight loss program. Each eating episode was entered into the computer as a separate behavioral observation resulting in 3066 usable observations. Log-linear analysis of multidimensional contingency tables was used to fit Markov chains to the data in order to examine whether dietary slips (overeating; unplanned eating) could be predicted from the following antecedents or pairs of antecedents: meal, people, place, mood, and hunger. Antecedents found to be associated with conditional probabilities 25 percent greater than the unconditional probabilities for unplanned meals and overeating (very much; some) are reported. Three basic categories of high-risk situations emerge: positive social interactions, negative emotions, and physiological craving. Individual differences were observed in the unconditional probabilities of the target behaviors, in exposure to high-risk situations, and in impulsive eating in response to meal, people, place, and hunger.

Adult↗

PubMed1982

Drug level monitoring in psychopharmacology: usefulness and clinical problems, with special reference to tricyclic antidepressants.

The gradual onset of action and pronounced pharmacokinetic variability provide a solid rationale for drug plasma level monitoring in psychopharmacology. For tricyclic antidepressants a well-established drug level therapeutic effect relationship is available for a few compounds (imipramine, nortiptyline, amitriptyline); and for these, plasma level monitoring can ensure more efficient and safe treatment. The relationship has been demonstrated only in endogenously depressed patients. Various pharmacokinetic problems such as dose-dependent kinetics (imipramine in elderly patients), autoinduction (chlorpromazine), drug interaction (inhibitory effect of neuroleptics on metabolism of tricyclic antidepressants), and changes in protein binding may be better controlled by monitoring the drug levels. In amitriptyline intoxications, a possible change in the elimination kinetics results in a very slow decline in plasma levels for several days; and plasma level measurements might help to identify those patients at prolonged risk of adverse reactions. Some side effects--in particular, orthostatic hypotension--occur at subtherapeutic drug levels and therefore cannot be prevented by drug level monitoring, and monitoring of other (physiological) variables is more important. Drug level monitoring of tricyclic antidepressants thus can be considered a valuable addition to the treatment program, but it cannot replace proper clinical practice in terms of diagnostic evaluation and control of patients.

Antidepressive Agents, Tricyclic↗

PubMed1999

Long-term multicenter experience with vagus nerve stimulation for intractable partial seizures: results of the XE5 trial.

OBJECTIVE: Intermittent stimulation of the left cervical vagus nerve trunk (VNS) with the NeuroCybernetic Prosthesis (NCP) is emerging as a novel adjunct in the management of medically refractory epilepsy. We review the safety and efficacy of VNS 1 year after completion of the E05 study, the largest controlled clinical trial of VNS to date. METHODS: One hundred and ninety-nine patients with intractable epilepsy and at least 6 complex partial or secondarily generalized seizures per month enrolled in a randomized, double-blinded, partial crossover trial of high versus low parameters of stimulation (E05). After 3 months, all patients received high stimulation during an open-label, nonblinded extension trial (XE5). Seizure frequency, adverse events and multiple physiologic variables were monitored at regular intervals. RESULTS: At 3 months, the mean reduction in seizure frequency among patients receiving high stimulation during E05 was 28%. Of the 199 subjects participating in this acute-phase trial, 195 continued in the long-term protocol. Among the latter patients, 21 subsequently exited the study due to lack of efficacy, and 2 others died from causes unrelated to VNS. Complete data were obtained for 164 of the remaining subjects. Using a declining N analysis, the mean and median reduction in seizure frequency at 15 months was 37 and 45%, respectively. A last visit carried forward analysis, which controls for dropouts and incomplete follow-up, yielded comparable results (34 and 45%, respectively), indicating little potential for selection bias. At 15 months, 39% of the subjects had a greater than 50% reduction in seizures, including 21% who had a greater than 75% reduction, and 2% have remained seizure free. Few serious adverse events, physiological perturbation or device failures were reported. CONCLUSIONS: The long-term multicenter safety, efficacy, feasibility and tolerability of VNS, as well as the durability of the NCP device have been confirmed. Unlike chronic therapy with antiepileptic medication, the efficacy of VNS is maintained during prolonged stimulation, and overall seizure control continues to improve with time.

Adult↗

PubMed2003

Cerebral fractional oxygen extraction in very low birth weight infants is high when there is low left ventricular output and hypocarbia but is unaffected by hypotension.

This study examined the relationships between cerebral fractional oxygen extraction (FOE), mean arterial blood pressure (MABP), left ventricular output (LVO), blood gases, and other physiologic variables in 36 very-low-birth-weight preterm infants during the first 3 d after birth. There was a decrease in cerebral FOE (p = 0.008), and rises in LVO (p < 0.0001) and MABP (p = 0.02) during the 3 d. Between d 1 and 2, cerebral FOE decreased (p = 0.007) and LVO increased (p < 0.0001). There was no relationship between MABP and cerebral FOE. LVO correlated negatively with cerebral FOE on d 1 (p = 0.01), but not on d 2 (p = 0.07). On d 1, median pressure of arterial CO(2) was lower in infants with low LVO (<5(th) centile) and high cerebral FOE (>95(th) centile) than in infants with low LVO (<5(th) centile) but normal cerebral FOE (5(th)-95(th) centile) (p = 0.03). These findings suggest that cerebral FOE was increased only when LVO was low and there was hypocarbia. MABP had no demonstrable effect. It is likely that increased cerebral FOE is a normal physiologic response to maintain an adequate oxygen supply to the cerebral tissues when LVO is low and hypocarbia has caused vasoconstriction. It is possible that the cerebral hemispheres are low-priority vascular beds in the preterm infant, and that the high cerebral FOE is a result of reduced hemispheric blood flow to maintain MABP in the presence of low LVO.

Humans↗

PubMed2003

An animal model for surgical anesthesia and analgesia: characterization with isoflurane anesthesia and remifentanil analgesia.

UNLABELLED: With a traditional clamp test alone, quantitative evaluation of the level of surgical anesthesia/analgesia is not easy. We have developed a rabbit model that allows for repeated quantification of the varying level of surgical anesthesia/analgesia using both mechanical and electrical stimulation as simulated surgical stimuli. After tracheostomy and intravascular cannulations under isoflurane anesthesia, eight rabbits were placed on a sling that allowed for free movement of the head and extremities. The inspired isoflurane concentration was reduced from 3% to 1.5% and then to 0%. Remifentanil was then infused at 4 graded infusion rates (0.1-0.8 microg. kg(-1) x min(-1)). At each drug dose, analgesic variables were determined including the number of animals behaviorally unresponsive to clamping the forepaw (nonresponders) and threshold voltage of subcutaneous electrical stimulation (2 Hz, 5 Hz, and 50 Hz) required to evoke the head lift (HLT, pain detection/arousal threshold) and escape movement responses (EMT, pain tolerance threshold). With increasing drug doses, HLTs and EMTs at 5 Hz increased dose-dependently and most proportionately to increases in the number of nonresponders, a standard indicator of the anesthetic/analgesic level. Therefore, using the HLT and EMT at 5 Hz combined with a clamp test, this rabbit model allows for quantitative evaluation of the varying level of surgical anesthesia/analgesia. IMPLICATIONS: We have developed a rabbit model of surgical anesthesia and analgesia using both mechanical and electrical stimulation as simulated surgical stimuli, which allows for repeated, quantitative, and qualitative evaluation of the varying level of surgical anesthesia and analgesia, differentiation between sedative/hypnotic and analgesic components of drug actions, and simultaneous monitoring of all the clinically relevant physiological variables including cardiovascular and respiratory variables.

Analgesia↗

PubMed2006

Psychophysiological effects of human-animal interaction: theoretical issues and long-term interaction effects.

This paper reviews literature published on the psychophysiological effects of long-term human-animal interaction (i.e., pet ownership, pet adoption). A literature search was conducted using PsycInfo and Medline databases. Although the available evidence is far from being consistent, it can be concluded that, in some cases, long-term relationships with animals may moderate baseline physiological variables, particularly blood pressure. Results proved more coherent in studies where animals were adopted by owners as part of the procedure. This paper examines existing hypotheses seeking to account for these effects and the supporting evidence. Two major hypotheses have been suggested to explain the psychophysiological effects of long-term interaction, namely (1) stress-buffering effects of noncritical social support provided by pets; and (2) classical conditioning of relaxation. These mechanisms may partially account for the long-term health outcomes observed in a number of human-animal interaction studies.

Adaptation, Psychological↗

PubMed1982

Modern patient care using biotelemetry: its potential and technical realization at present and in the future.

Incorporation of biotelemetry has a number of advantages, such as reduction of the impediment of the information source (patient, subject or animal) reduction of the psychological effects on the information source, reduction of measuring artifacts, reduction of the risk for electroshock, reduction of the complexity of monitoring of physiological variables, as well as a potential reduction of the total cost of patient care. Therefore, biotelemetry may be incorporated advantageously not only in areas where this technique is absolutely needed (sport, work, function control during realistic circumstances of activity), but also in other areas such as patient monitoring during intensive care and in the operating room. There have been a number of drawbacks in biotelemetry for application in patient monitoring in the past mainly due to the problem of frequency allocations and regulations, but with the newly developed infrared systems future applications of biotelemetry in clinical monitoring seems promising.

Ambulatory Care↗

PubMed2001

Activation of Gi-coupled receptors releases a tonic state of inhibited platelet aggregation.

Single-receptor pharmacology does not satisfactorily explain the physiology of the ADP-induced platelet aggregation response. It has been shown that, in addition to Gq-coupled receptor activation, one Gi-coupled receptor, either the ADP P2T or the alpha2-adrenoceptor, is required for elicitation of aggregation. The underlying mechanism of this action, however, has not been elucidated. By systematically assaying the entire time course of the aggregation and its fade using two methods of aggregometry, we have investigated the role of graded activation of these two Gi-coupled receptors. We demonstrate that constant activation of either of two Gq-coupled receptors, the ADP P2Y1 or the 5-HT2A, and incremental activation of either of the two Gi-coupled receptors, tightly regulates the aggregation response in vitro, through the apparent release of a tonic inhibition of platelet aggregation. This tightly regulated release of inhibition, which appears analogous to the phenomena of disinhibition observed in the central nervous system, may be instrumental for the continuous adaptation of the aggregation response to variable physiological conditions.

Adaptation, Physiological↗

PubMed2003

[Vital signs of hemodynamic monitoring].

The aim of hemodynamic monitoring in intensive care is to recognize derangements in physiologic variables, which herald the progression toward organ failure. Traditionally the term "vital signs" refers to heart rate, arterial pressure, respiratory rate and body temperature monitoring. Continuous monitoring of vital signs, is advocated, since trends are more significant than single measurements, and is still a cornerstone, in the hemodynamic evaluation of a critically ill patient. Nevertheless, the spectrum of hemodynamic derangements that can arise during intensive care unit stay is very large and often additional information, beside the vital signs, are needed to evaluate correctly the individual patient.

Blood Pressure↗

PubMed1991

Circadian variation in blood pressure: considerations for therapy.

Accurate measurement of blood pressure is a primary requirement of studies in hypertension and its treatment. However, this is not an easy objective to achieve with sphygmomanometric methods of measurement. Intra-arterial monitoring is an objective method of blood pressure measurement that has become popular in studies of hypertension since its introduction in the 1960s. Since that time the technique has been used to characterize the now well-accepted physiological variability in blood pressure. The clinical significance of such observations is still the subject of active debate. However, it seems clear that, as blood pressure rises sharply in the morning and this occurs at around the same time as the peak incidence of serious cardiovascular events, antihypertensive therapy should control blood pressure effectively at this time. This article summarizes results from some studies, using intra-arterial blood pressure monitoring to indicate the importance of blood pressure variation, 24-h blood pressure control and experience with antihypertensive drugs of various pharmacological classes.

Amlodipine↗

PubMed1984

[Histologic thyroid gland findings in the newborn infant and infant, with special reference to sudden infant death].

The morphological picture of the thyroid gland, the only endocrine organ with a follicle structure, allows a limited conclusion to be drawn with respect to the functional state in spite of any physiological variability. The thyroid of the newborn shows total colloid release and collapse of the follicles. The regular structure of the thyroid will be rebuilt within several weeks after birth. Total colloid absorption can be found in cases of stress-activated thyroids as well as in cases of death due to freezing. A histological examination was done on 88 thyroids of fetuses, newborns and infants. About 70% of the results on 27 cases of sudden infant death syndrome (SIDS) may be interpreted as a morphological correlate of a premortal chronic or recurrent stress reaction. The value of these results is discussed.

Child, Preschool↗

PubMed2000

Beneficial physiological and performance responses to a month of restricted energy intake in healthy overweight women.

Changes in mood, performance, cortisol, and physiological variables with a month-long energy restricting diet (3.347 MJ/day) were studied in nine overweight (mean mass 71.2 +/- 8 kg; body mass index 26.1 +/- 2.8 kg/m(2)), healthy premenopausal (age 20-36 years) women. Measurements were taken in the 2 weeks before the diet (baseline) and again in the final 2 weeks of the diet to attenuate menstrual cycle differences. A reduction in energy intake and concomitant weight loss (5.80 +/- 1.65 kg) were accompanied by a significant decline in systolic blood pressure (5.4%), heart rate (7.6%), and cortisol concentration (13.6%). Fatigue and vigour on the Profile of Mood States (POMS) questionnaire were adversely affected; however, subjective assessments of mood, concentration, temperature sensitivity, appetite, and sleep quality using visual analogue scales, were not significantly altered during the month-long period of energy restriction. Motor performance, as assessed by hand-eye coordination, improved with both a reduction in mean reaction time and improved accuracy in response to visual stimuli. The very low-energy diet appeared to be neither physiologically nor psychologically stressful. Beneficial effects were evident with a reduction in BMI, reduced risk of cardiovascular stress, improved motor performance, and a decline in physiological stress with dieting success.

Adult↗

PubMed2003

Physiological responses to multiple speed treadmill walking for Syme vs. transtibial amputation--a case report.

PURPOSE: To date, there have been no longitudinal studies comparing walking at different levels of amputation. The objective of this study was to compare the self-selected walking velocity (SSWV) and selected physiologic variables during walking between a Syme and a later transtibial level of amputation for a single subject. Additional comparison was made between the SACH foot prosthesis and a dynamic response foot prosthesis. METHOD: A 35-year-old male with a traumatic Syme amputation later underwent elective transtibial amputation. SSWV and multiple speed treadmill walking tests (53.64, 67.05, 80.46, 93.87 and 107.28 m/min) were evaluated under three conditions (Syme prosthesis with SACH foot, transtibial prosthesis with SACH foot, and transtibial prosthesis with Flex-Foot). RESULTS: Walking with transtibial prosthesis showed minimal differences in oxygen consumption (0 - 5% reduction), heart rate response (0 - 1% reduction), or gait efficiency (0 - 5% improvement) across all speeds when compared with Syme prosthesis (both with SACH foot). However, the SSWV was 6 - 8% faster for the transtibial SACH foot. Walking with transtibial Flex-Foot required less cardiovascular demand than with transtibial SACH foot at higher speeds. CONCLUSIONS: In this case report, it seemed that transtibial amputation did not have adverse effects on selected physiological responses at a variety of walking speeds when compared to Syme amputation, and that the use of a dynamic response foot enhanced his gait performance. Further experimental studies involving more subjects with traumatic Syme and transtibial amputations are required to better understand the effect of these two levels of amputation on energy cost of walking.

Adult↗