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PubMed1994

Relationship between patient self-ratings and physician ratings of general health, depression, and anxiety.

OBJECTIVE: To examine the relationship between patient self-ratings and physician ratings of general health, depression, and anxiety and patient and physician ratings in comparison to Diagnostic Interview Schedule (DIS) diagnoses of depression and anxiety. DESIGN: Observational study. SETTING: A general medical outpatient clinic. PATIENTS: Clinic attendees. METHOD: Consecutive clinic attendees on randomly selected days completed a self-reported screening questionnaire for hypochondriasis, composed of the Whiteley Index and the Somatic Symptom Inventory. A random sample of patients (N = 79), 95% of whom had scores below the cutoff for hypochondriasis (n = 75) and 5% of whom had scores at or above the cutoff for hypochondriasis (N = 4), returned at a later date to complete a research battery consisting of self-reported questionnaires, structured and semistructured interviews, and a structured interview for diagnoses of anxiety and depression based on the DIS, which used criteria from the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition. OUTCOME MEASURES: Responses to questionnaires and interviews. RESULTS: Agreement between patients and physicians was statistically significant concerning patients' physical health, depression, and anxiety. Based on one question, both physicians' and patients' ratings of depression and anxiety compared favorably with DIS diagnoses. By means of receiver operating characteristics analysis, values for the areas under the curve and their SEs were as follows: for depression, 0.789 +/- 0.075 for patient self-ratings and 0.825 +/- 0.054 for physician ratings; for anxiety, 0.734 +/- 0.058 for patient self-ratings and 0.667 +/- 0.065 for physician ratings. CONCLUSION: One simple question about a patient's status with respect to depression or anxiety is sufficient to detect these disorders with high sensitivity and specificity, yielding values comparable to those yielded by instruments consisting of many items. Asking patients to rate their own levels of depression and anxiety may constitute one portion of the family physician's diagnostic assessment for these conditions.

Anxiety Disorders↗
PubMedDate not supplied

Tracking of physical fitness components in boys and girls from the second to sixth grades.

The purpose of this study was to examine the tracking of field-assessed fitness components in boys and girls from the second to sixth grades. A total of 857 children (448 boys and 409 girls) from 11 urban schools were tested in grade 2; 565 children (297 boys and 268 girls) were tested again in grade 6. Only subjects who had completed all fitness tests on the two occasions were included in the analysis (n = 319: 203 boys and 116 girls). Fitness tests included a 600-m run, a flying-start sprint, the standing long jump, and a medicine ball throw. Additionally, subjects performed a skill task that involved slalom dribbling of a basketball. Baseline scores in grade 2 were correlated (Spearman Rank Order) with scores attained in grade 6. Boys had significantly (P < 0.05) better scores in all fitness tests compared with girls in both grades. Tracking of fitness components over the 4-year period in both sexes varied between 0.36 and 0.66. Tracking was consistently lower in girls than in boys, perhaps reflecting their earlier maturation.

Bias↗
PubMed2006

Transient versus prolonged hyperlocomotion following lateral fluid percussion injury in mongolian gerbils.

Posttraumatic hyperactivity is a neurobehavioral symptom commonly seen in patients after traumatic brain injury (TBI). No useful animal model has yet been established for evaluation of this important symptom. We induced either mild (MILD, 0.7-0.9 atm) or moderate (MOD, 1.3-1.6 atm) lateral fluid percussion injury (LFPI) in Mongolian gerbils. Open-field and T-maze tests were used during a 7-day period after the trauma. All animals were perfusion fixed for histopathological examinations. Transient locomotor hyperactivity was found with a peak at 6 hr after injury in the MILD animals, whereas MOD animals showed prolonged and severe hyperlocomotion throughout the 7-day posttrauma period (P < 0.0001). Interestingly, the temporal profile of the posttraumatic hyperactivity was similar to that of the working memory deficit in both injury groups. Histological examination revealed significant neural tissue damages, including cortical necrosis, white matter rarefaction, and neuronal loss in the hippocampus in the ipsilateral hemisphere of the MOD animals, vs. only negligible changes in the MILD animals. Correlation analysis revealed that the volume of white matter lesions was significantly correlated with both posttraumatic hyperactivity (r = 0.591, P < 0.01) and working memory deficit (r = -0.859, P < 0.0001). Taken together, our findings confirm the successful reproduction of posttraumatic hyperactivity following experimental TBI. The posttraumatic hyperlocomotion probably shared pathomechanisms common to those of cognitive dysfunction caused by LFPI, supporting the speculation from previous studies that some neurobehavioral abnormities intimately correlate with TBI-induced cognitive dysfunction. Histopathologically, significant involvement of white matter damage in the posttraumatic functional deficits was indicated.

Analysis of Variance↗
PubMed1992

Day-to-day changes in oxygen uptake kinetics at the onset of exercise during strenuous endurance training.

The aim of this study was to assess the effect of strenuous endurance training on day-to-day changes in oxygen uptake (VO2) on-kinetics (time constant) at the onset of exercise. Four healthy men participated in strenuous training for 30 min.day-1, 6 days.week-1 for 3 weeks. The VO2 was measured breath-by-breath every day except Sunday at exercise intensities corresponding to the lactate threshold (LT) and the onset of blood lactate accumulation (OBLA) which were obtained before training. Furthermore, an incremental exercise test was performed to determine LT, OBLA and maximal oxygen uptake (VO2max) before and after the training period and every weekend. The 30-min heavy endurance training was performed on a cycle ergometer 5 days.week-1 for 3 weeks. Another six men served as the control group. After training, significant reductions of the VO2 time constant for exercise at the pretraining LT exercise intensity (P less than 0.05) and at OBLA exercise intensity (P less than 0.01) were observed, whereas the VO2 time constants in the control group did not change significantly. A high correlation between the decrease in the VO2 time constant and training day was observed in exercise at the pretraining LT exercise intensity (r = -0.76; P less than 0.001) as well as in the OBLA exercise intensity (r = -0.91; P less than 0.001). A significant reduction in the blood lactate concentration during submaximal exercise and in the heart rate on-kinetics was observed in the training group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1977

[Experiences with a cardiorecorder system for continuous 24-hour registration of heart rate].

Studies regarding to the continuous registration of the heart frequency by a transportable instrument, which can store the data of the heart frequency per minute up to 24h, are presented. It is a tape recorder the speed of which is geared down. Thus a normal tape cassette C 60 is sufficient for a registration of the heart frequency during 2 X 24h. The R-wave of the ECG is registered on the first channel of the tape as a biological signal. Moreover every minute an impulse of a clock is recorded on the second channel of the tape. With help of a second instrument the play back procedure for the 24-h-recording can be performed in about 15 min. The signals of both channels of the tape are transformed in digital rectangle impulses by an installed impulse-converter. The serial impulses are counted per minute with help of the time-mark by an interface in a counter. These data are at disposal in BCD-code. They can be passed on the following peripherals: digital printer, computer, pen-recorder and so on. A parallel standardized recording of the physical activity observed by the subject or by an experimenter allows a statistical evaluation and comparison of the physical activity with the corresponding heart frequency data. Some examples of the aread of occupational health, epidemiology and exercise physiology are discussed.

Electrocardiography↗
PubMed1984

Ultrastructural aspects of cytoplasmic ribosomes from Histoplasma capsulatum and Blastomyces dermatitidis as revealed by heavy metal staining.

Cytoplasmic ribosomes were isolated and purified from sonicates of the mycelial and yeastlike growth forms of the pathogenic dimorphic fungi, Histoplasma capsulatum and Blastomyces dermatitidis. Similar ribosomal fractions were prepared from Neurospora crassa and Saccharomyces cerevisiae. These latter organisms were selected as typical filamentous and yeastlike monophasic fungi, and their ribosomes were used as reference standards. High resolution electron microscopy permitted a comparison of both positively and negatively-stained ribosomes to those dehydrated without heavy metal salt. Such studies revealed statistically significant differences in physical dimensions. Cautious interpretations of substructural detail of the various ribosomal preparations suggested both interphasic and interspecies differences.

Blastomyces↗
PubMed1984

The effects of a number of short-term exogenous stimuli on pineal serotonin-N-acetyltransferase activity in rats.

The present study deals with the question as to what extent the sympathetically innervated rat pineal gland is affected by a number of short-term exogenous stimuli given during day-time, as assessed by measuring pineal serotonin-N-acetyltransferase activity (NAT) which is directly proportional to melatonin formation. In male Sprague-Dawley rats kept under LD 12:12 pineal NAT was statistically significantly depressed by physical immobilization for 2 hours, swimming for 15 min in water of 10 and 30 degrees C, exposure for 2 hours to cold (5 degrees C) or heat (40 degrees C), noise (90 db) for 2 hours and hunger for 17 hours. An increase in NAT was noted after swimming for 15 min in water of 20 degrees C. No effect was detectable after 17 hours of thirst or hunger combined with thirst and in one of 2 experiments involving exposure to heat (40 degrees C, 2 hours) and insulin-induced hypoglycemia. In animals kept under continuous illumination for 48 hours, immobilization resulted in a slightly smaller decrease than under LD 12:12 and insulin-induced hypoglycemia led to a striking increase of NAT. As the changes in pineal NAT are brought about by rather strong exogenous stimuli it is suspected that the rat pineal gland during day-time is not very susceptible to ambient factors of normal range.

Acetyltransferases↗
PubMed1996

Computational sequence analysis of matrix metalloproteinases.

Matrix metalloproteinases (MMP) play a cardinal role in the breakdown of extracellular matrix involved in a variety of biological and pathological processes. Research on MMPs has classified and characterized these enzymes according to their matrix substrate specificity, gene and protein domain structure, and regulation of activity and expression. However, the discovery of new MMPs has introduced a need for a more comprehensive and systematic method of classification and quantitative comparison of known and newly discovered members. This study compiles a sequence alignment, constructs a dendrogram, and calculates physical data and homology percentage assignments in order to obtain further insight into MMP structure-function relationships. Thorough analysis of MMP primary sequence domains, physical data patterns, and statistical analysis of sequence homology yields higher resolution in the similarities and differences that group MMP members.

Algorithms↗
PubMed2000

New, simple approach for maximal pudendal nerve exposure: anomalies and prospects for functional reconstruction.

PURPOSE: Functional neosphincters after pudendal nerve anastomosis proved possible in animal models and may be applicable in humans, but access is a recognized problem. We report the occurrence of pudendal nerve anomalies, its implications for reconstruction, and describe a new approach for maximal exposure. METHODS: Adult human cadavers were positioned prone and dissected via a gluteal approach. Pudendal nerve variations and physical measurements were analyzed statistically. RESULTS: A new, simple, four-step approach (surface landmarks and exposure of gluteus maximus muscle, sacrotuberous ligament, and pudendal neurovascular bundle) permitted optimal pudendal nerve exposure in all 14 human cadavers (28 limbs). Six were males and had a mean age of 82 (range, 58-102) years. Two anomalies, Type 1 (2-trunked) and Type 2 (3-trunked), of the pudendal nerve were recognized in 30 percent of cadavers, with a left-to-right ratio of 2.5:1. Mean pudendal nerve length over the ischial spine was 23.9 (range, 19-28) mm right, 24.2 (range, 19-28) mm left (P = 0.54), but its diameter measured 5.2 mm (right) and 4.9 mm (left; P = 0.04). Mean length of pudendal nerve trunk exposed after reflection of the sacrotuberous ligament was 55 (range, 44-75) mm on either side before division into terminal branches. The number and percent frequency of inferior rectal nerve on both sides were 1 (13 percent), 2 (76 percent), and 3 (11 percent), respectively, with a mean length of 27.1 (range, 21-34) mm right and 27.9 (range, 20-33) mm left (P = 0.31). CONCLUSION: A simple four-step approach to the pudendal nerve contributes to improved access in all cases. It facilitates reconstruction because it allows accurate nerve selection and recognition of potential anomalies that might influence functional outcome.

Aged↗
PubMed2004

EEG coherence changes between right and left motor cortical areas during voluntary muscular contraction.

It is known that movements of the right side of the body are controlled by the left motor cortex of the brain. The aim of this study is to evaluate the contribution of right motor cortex of the brain in the central motor control of right-sided muscle contraction. EEG/EEG coherence analysis has been used to determine the functional coupling between the right and left motor cortical areas in twenty normal volunteers, during maximum voluntary contraction (MVC) and 50% MVC of right Adductor Pollicis muscle (APM). It shows that the maximum mean coherence values were: 0.751 during MVC at 10 and 12 Hz, and 0.274 during 50% of MVC at 22 Hz. The minimum mean coherence values were: 0.716 during MVC at 48 and 50 Hz, and 0.242 during 50% MVC at 34 Hz. The high coherence values obtained during MVC, and to a lesser extent during 50% of MVC, could be attributed to the need of recruitment of both motor cortical areas during the decision phase of central motor control of voluntary muscular contraction. The "will" to perform maximum voluntary contraction could be a major factor, which contribute to the higher coherence values obtained during MVC than these associated with 50% of MVC.

Adult↗
PubMed2006

Evaluation of lower leg function in patients with Achilles tendinopathy.

Achilles tendinopathy is considered to be one of the most common overuse injuries in elite and recreational athletes. However, the effect that the Achilles tendinopathy has on patients' physical performance is still unclear. The purpose of this study was to evaluate if Achilles tendinopathy caused functional deficits on the injured side compared with the non-injured side in patients. A test battery comprised of tests for different aspects of muscle-tendon function of the gastrocnemius, soleus and Achilles tendon complex was developed to evaluate lower leg function. The test battery's test-retest reliability and sensitivity (the percent probability that the tests would demonstrate abnormal lower limb symmetry index in patients) were also evaluated. The test battery consisted of three jump tests, a counter movements jump (CMJ), a drop counter movement jump (drop CMJ) and hopping, and two strength tests, concentric toe-raises, eccentric-concentric toe-raises and toe-raises for endurance. The reliability was evaluated through a test-retest design on 15 healthy subjects. The test battery's sensitivity and possible functional deficits in patients with Achilles tendinopathy were evaluated on 42 patients (19 women and 23 men). An excellent reliability was found between test days 1-2 and 2-3 for all tests (ICC = 0.76-0.94) except for concentric toe-raise, test 2-3, which had fair reliability (ICC = 0.73). The methodological error ranged from 8 to 17%. There were significant differences (P = 0.001-0.049) between the non-injured (or least symptomatic) side and injured (most symptomatic) side for hopping, drop CMJ, concentric and eccentric-concentric toe-raises, and significant differences (P = 0.000-0.012) in the level of pain during CMJ, hopping, and drop CMJ. The sensitivity of the test battery at a 90% capacity was 88. Achilles tendinopathy causes not only pain and symptoms in patients but also apparent impairments in various aspects of lower leg muscle-tendon function as measured with the test battery. This test battery is reliable and able to detect differences in lower leg function between the injured or "most symptomatic" and non-injured or "least symptomatic" side in patients with Achilles tendinopathy. The test battery has higher demand on patients' function compared with each individual test.

Achilles Tendon↗
PubMed2003

Oxygen uptake kinetics during moderate, heavy and severe intensity "submaximal" exercise in humans: the influence of muscle fibre type and capillarisation.

The purpose of the present study was to test the hypothesis that muscle fibre type influences the oxygen uptake (.VO(2)) on-kinetic response (primary time constant; primary and slow component amplitudes) during moderate, heavy and severe intensity sub-maximal cycle exercise. Fourteen subjects [10 males, mean (SD) age 25 (4) years; mass 72.6 (3.9) kg; .VO(2peak) 47.9 (2.3) ml kg(-1) min(-1)] volunteered to participate in this study. The subjects underwent a muscle biopsy of the vastus lateralis for histochemical determination of muscle fibre type, and completed repeat "square-wave" transitions from unloaded cycling to power outputs corresponding to 80% of the ventilatory threshold (VT; moderate exercise), 50% (heavy exercise) and 70% (severe exercise) of the difference between the VT and .VO(2peak). Pulmonary .VO(2) was measured breath-by-breath. The percentage of type I fibres was significantly correlated with the time constant of the primary .VO(2) response for heavy exercise (r=-0.68). Furthermore, the percentage of type I muscle fibres was significantly correlated with the gain of the .VO(2) primary component for moderate (r=0.65), heavy (r=0.57) and severe (r=0.57) exercise, and with the relative amplitude of the .VO(2) slow component for heavy (r=-0.74) and severe (r=-0.64) exercise. The influence of muscle fibre type on the .VO(2) on-kinetic response persisted when differences in aerobic fitness and muscle capillarity were accounted for. This study demonstrates that muscle fibre type is significantly related to both the speed and the amplitudes of the .VO(2) response at the onset of constant-load sub-maximal exercise. Differences in contraction efficiency and oxidative enzyme activity between type I and type II muscle fibres may be responsible for the differences observed.

Adaptation, Physiological↗
PubMed2003

Relationship between shot put performance and triceps brachii fiber type composition and power production.

It is commonly accepted that shot put performance is mainly determined by the ability of the lower body to produce power. The purpose of the present study was to investigate the relationship between shot put performance and triceps brachii muscle fiber type composition and strength capacity. Thirteen male physical education students were selected to participate in the study based upon their shot put performance after 5 weeks of shot put technique instruction. At the completion of this technique-instruction period, they performed the following tests: shot put with a 6-kg shot, isokinetic torque measurements of the elbow extensors at 0, 0.52, 1.04, 1.57, 2.09, 3.14, and 4.19 rad.s(-1), maximal strength (1 RM) and explosive-throwing bench-press tests, one-arm seated shot put with 1-, 2-, 3-, 4-, 5- and 6-kg shot. Whole-body and dominant upper-arm bioimpedance measurements were used to estimate whole-body and upper-arm muscle mass. Muscle biopsy samples from the long head of the dominant triceps brachii were obtained and analyzed for fiber type composition with ATPase histochemistry. Shot put performance was significantly correlated with type II fiber area ( r=0.70, P<0.01), one-arm seated shot put (range r=0.60 to r=0.79, P<0.05), elbow extensors' isokinetic torque (range r=0.65 to r=0.78, P<0.05), bench-press tests ( r>0.86, P<0.01) and estimated arm muscle cross-sectional area ( r=0.68, P<0.05). These results suggest that fiber type composition and the functional capacity of triceps brachii muscle (e.g., isokinetic torque) explain a part of shot put performance. The magnitude of the correlation coefficients between shot put and the upper-body power tests suggests that other body parts (e.g., lower extremities) may play a significant role in this event.

Adult↗
PubMed2003

Reduced oxygen uptake increase to work rate increment (DeltaVO2/DeltaWR) is predictable by VO2 response to constant work rate exercise in patients with chronic heart failure.

Patients with reduced peak oxygen uptake (VO2) due to chronic heart failure (CHF) exhibit abnormal VO2 kinetics even during mild to moderate exercise. This is characterized by a reduced ratio of the VO2 increase to the work rate increment (DeltaVO2/DeltaWR) during ramp exercise, and by a slow increase in VO2 during constant work rate exercise. Because the slow kinetics alone is unlikely to explain the reduced DeltaVO2/DeltaWR on theoretical grounds, we can postulate that the linearity between work rate and VO2 may be impaired when exercise is imposed in a ramp fashion. The present study was designed to address this issue. In 21 CHF patients and 17 normal controls, we performed both symptom-limited exercise testing (15 W. min(-1) ramp) and a constant work rate exercise test (0 W followed by 50-W step). The VO2 step response was used to mathematically derive the hypothetical VO2 ramp response by time integration. Although peak VO2 and work rate were both significantly lower in patients, the attenuation in peak VO2 was more prominent ( p<0.05), which could be explained by a lower DeltaVO2/DeltaWR in patients compared with controls [8.1 (SD 1.0) and 9.8 (0.5) ml. min(-1). W(-1), p<0.01]. The hypothetical DeltaVO2/DeltaWR derived from the VO2 step response was also significantly lower in patients [8.7 (1.0) and 10.0 (0.7) ml. min(-1). W(-1), p<0.01]. The hypothetical and measured DeltaVO2/DeltaWR were highly correlated ( r=0.78, p<0.001). Thus, we can reasonably predict the VO2 ramp response from the VO2 response to a step increase in work rate, indicating that linearity between VO2 and work rate is held constant irrespective of loading patterns. Additional studies, such as those including evaluation of anaerobic bioenergetics, are needed to further elucidate the precise mechanism(s) of this phenomenon.

Chronic Disease↗
PubMed2003

Peak exercise oxygen uptake and left ventricular systolic and diastolic function and arterial mechanics in healthy young men.

Echocardiography can be used to estimate myocardial contractility by the assessment of the circumferential end-systolic stress-corrected left ventricular (LV) fractional shortening measured at midwall level (stress-corrected MWS). Whether stress-corrected MWS at rest predicts exercise peak oxygen uptake (peak VO(2)) is unknown. Also, it is not known whether the propagation rate of the early LV filling wave (E wave propagation rate, V(p)), a new pre-load insensitive index of LV diastolic function, and echocardiographically assessed indices of arterial stiffness correlate to peak VO(2). Accordingly, we performed echocardiographic studies and exercise tests with respiratory gas analysis in 15 young healthy male subjects (mean age 27 years, range 18-36). Neither stress-corrected-MWS ( r=0.20, P=NS) nor ejection fraction ( r=-0.05, P=NS) correlated significantly with peak VO(2). Adjustment for age and resting heart rate had no effect on the results. In separate multiple regression models adjusting for standard covariates (age, LV size and heart rate), peak VO(2) correlated with V(p) (beta=0.98, P<0.01), as well as with E/A (beta=0.85, P<0.01), and with the isovolumic relaxation time (indicator of LV relaxation) (beta=-0.59, P<0.05). Arterial stiffness indices showed no significant relation to peak VO(2). We conclude that in young healthy male subjects, resting myocardial contractility and arterial stiffness are not significant correlates of peak VO(2), whereas LV diastolic function, and in particular V(p), influences the variability of peak VO(2).

Adolescent↗