Respecified larval proleg and body wall muscles circulate hemolymph in developing wings of Manduca sexta pupae.
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Most larval external muscles in Manduca sexta degenerate at pupation, with the exception of the accessory planta retractor muscles (APRMs) in proleg-bearing abdominal segment 3 and their homologs in non-proleg-bearing abdominal segment 2. In pupae, these APRMs exhibit a rhythmic 'pupal motor pattern' in which all four muscles contract synchronously at approximately 4 s intervals for long bouts, without externally visible movements. On the basis of indirect evidence, it was proposed previously that APRM contractions during the pupal motor pattern circulate hemolymph in the developing wings and legs. This hypothesis was tested in the present study by making simultaneous electromyographic recordings of APRM activity and contact thermographic recordings of hemolymph flow in pupal wings. APRM contractions and hemolymph flow were strictly correlated during the pupal motor pattern. The proposed circulatory mechanism was further supported by the findings that unilateral ablation of APRMs or mechanical uncoupling of the wings from the abdomen essentially abolished wing hemolymph flow on the manipulated side of the body. Rhythmic contractions of intersegmental muscles, which sometimes accompany the pupal motor pattern, had a negligible effect on hemolymph flow. The conversion of larval proleg and body wall muscles to a circulatory function in pupae represents a particularly dramatic example of functional respecification during metamorphosis. (+info)
Thermal heterogeneity within human atherosclerotic coronary arteries detected in vivo: A new method of detection by application of a special thermography catheter.
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BACKGROUND: Activated macrophages play an important role in the pathogenesis of acute ischemic syndromes. It has been postulated that detection of heat released by activated inflammatory cells of atherosclerotic plaques may predict plaque rupture and thrombosis. Previous ex vivo studies have shown that there is thermal heterogeneity in human carotid atherosclerotic plaques. METHODS AND RESULTS: To measure the temperature of human arteries in vivo, we developed a catheter-based technique. Ninety patients (45 with normal coronary arteries, 15 with stable angina [SA], 15 with unstable angina [UA], and 15 with acute myocardial infarction [AMI]) were studied. The thermistor of the thermography catheter has a temperature accuracy of 0.05 degrees C, a time constant of 300 ms, and a spatial resolution of 0.5 mm. Temperature was constant within the arteries of the control subjects, whereas most atherosclerotic plaques showed higher temperature compared with healthy vessel wall. Temperature differences between atherosclerotic plaque and healthy vessel wall increased progressively from SA to AMI patients (difference of plaque temperature from background temperature, 0. 106+/-0.110 degrees C in SA, 0.683+/-0.347 degrees C in UA, and 1. 472+/-0.691 degrees C in AMI). Heterogeneity within the plaque was shown in 20%, 40%, and 67% of the patients with SA, UA, and AMI, respectively, whereas no heterogeneity was shown in the control subjects. CONCLUSIONS: Thermal heterogeneity within human atherosclerotic coronary arteries was shown in vivo by use of a special thermography catheter. This heterogeneity is larger in UA and AMI, suggesting that it may be related to the pathogenesis. (+info)
Thermal image analysis of electrothermal debonding of ceramic brackets: an in vitro study.
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This study used modern thermal imaging techniques to investigate the temperature rise induced at the pulpal well during thermal debonding of ceramic brackets. Ceramic brackets were debonded from vertically sectioned premolar teeth using an electrothermal debonding unit. Ten teeth were debonded at the end of a single 3-second heating cycle. For a further group of 10 teeth, the bracket and heating element were left in contact with the tooth during the 3-second heating cycle and the 6-second cooling cycle. The average pulpal wall temperature increase for the teeth debonded at the end of the 3-second heating cycle was 16.8 degrees C. When the heating element and bracket remained in contact with the tooth during the 6-second cooling cycle an average temperature increase of 45.6 degrees C was recorded. (+info)
Polyangiitis overlap syndrome with eosinophilia associated with an elevated serum level of major basic protein.
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Polyangiitis overlap syndrome is a new disease entity and the reported cases in the literature are still limited. We describe a female patient presenting with finger ulcers, skin eruptions, pleural effusion, interstitial pneumonia and eosinophilia. Skin biopsy showed systemic small-sized angiitis and thrombosis. She was diagnosed as having polyangiitis overlap syndrome and was successfully then treated with corticosteroid. It is also of interest that the disease activity was correlated with the number of eosinophils in peripheral blood. The measurement of the serum level of major basic protein released from eosinophils functioning as a coagulant indicated the possible association of eosinophilia with thrombosis and polyangiitis. (+info)
Thermatomal changes in cervical disc herniations.
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Subjective symptoms of a cool or warm sensation in the arm could be shown objectively by using of thermography with the detection of thermal change in the case of radiculopathy, including cervical disc herniation (CDH). However, the precise location of each thermal change at CDH has not been established in humans. This study used digital infrared thermographic imaging (DITI) for 50 controls and 115 CDH patients, analyzed the data statistically with t-test, and defined the areas of thermatomal change in CDH C3/4, C4/5, C5/6, C6/7 and C7/T1. The temperature of the upper trunk and upper extremities of the control group ranged from 29.8 degrees C to 32.8 degrees C. The minimal abnormal thermal difference in the right and left upper extremities ranged from 0.1 degree C to 0.3 degree C in 99% confidence interval. If delta T was more than 0.1 degree C, the anterior middle shoulder sector was considered abnormal (p < 0.01). If delta T was more than 0.3 degree C, the medial upper aspect of the forearm and dorsal aspect of the arm, some areas of the palm and anterior part of the fourth finger, and their opposite side sectors and all dorsal aspects of fingers were considered abnormal (p < 0.01). Other areas except those mentioned above were considered abnormal if delta T was more than 0.2 degree C (p < 0.01). In p < 0.05, thermal change in CDH C3/4 included the posterior upper back and shoulder and the anterior shoulder. Thermal change in CDH C4/5 included the middle and lateral aspect of the triceps muscle, proximal radial region, the posterior medial aspect of the forearm and distal lateral forearm. Thermal change in CDH C5/6 included the anterior aspects of the thenar, thumb and second finger and the anterior aspects of the radial region and posterior aspects of the pararadial region. Thermal change in CDH C6/7 included the posterior aspect of the ulnar and palmar region and the anterior aspects of the ulnar region and some fingers. Thermal change in CDH C7/T1 included the scapula and posterior medial aspect of the arm and the anterior medial aspect of the arm. The areas of thermal change in each CDH included wider sensory dermatome and sympathetic dermatome. There was a statistically significant change of temperature in the areas of thermal change in all CDH patients. In conclusion, the areas of thermal change in CDH can be helpful in diagnosing the level of disc protrusion and in detecting the symptomatic level in multiple CDH patients. (+info)
Use of infrared thermographic calorimetry to determine energy expenditure in preterm infants.
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BACKGROUND: Measurement of infant energy expenditure in the clinical setting is difficult and is rarely done. Both indirect and direct calorimetry require long measurement periods and frequent calibration. OBJECTIVE: The objective of this study was to validate in infants a newly developed method of determining energy expenditure, infrared thermographic calorimetry (ITC), against an established method, respiratory indirect calorimetry (IC). ITC measures mean infant body surface temperature. ITC was used in conjunction with heat loss theory to calculate radiant, convective, evaporative, and conductive heat losses and thereby determine total energy expenditure. DESIGN: Ten healthy preterm infants were studied by obtaining concurrent ITC and IC measurements over a 3.5-5.5-h study period. Continuous IC measurements were compared with ITC measurements taken every 10 min during study periods. IC values were summed over 10-min intervals covering the 5 min before and 5 min after each ITC measurement, to allow comparisons between the 2 methods. RESULTS: Comparison of paired ITC and IC mean measurements for all 10 infants over the entire study period showed no significant difference between the 2 methods. However, individual paired IC and ITC values were significantly different for 7 of 10 infants. The overall mean difference between the 2 methods was 1.3%. CONCLUSIONS: ITC is an accurate, noninvasive method for measurement of heat loss and energy expenditure in healthy preterm infants, and therefore it may be a useful clinical and research tool. (+info)
Selective heating of vibrissal follicles in seals (Phoca vitulina) and dolphins (Sotalia fluviatilis guianensis).
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The thermal characteristics of the mystacial vibrissae of harbour seals (Phoca vitulina) and of the follicle crypts on the rostrum of the dolphin Sotalia fluviatilis guianensis were measured using an infrared imaging system. Thermograms demonstrate that, in both species, single vibrissal follicles are clearly defined units of high thermal radiation, indicating a separate blood supply to these cutaneous structures. It is suggested that the high surface temperatures measured in the area of the mouth of the follicles is a function of the sinus system. In seals and dolphins, surface temperature gradually decreased with increasing distance from the centre of a follicle, indicating heat conduction from the sinus system via the follicle capsule to adjacent tissues. It is suggested that the follicular sinus system is a thermoregulatory structure responsible for the maintenance of high tactile sensitivity at the extremely low ambient temperatures demonstrated for the vibrissal system of seals. The vibrissal follicles of odontocetes have been described as vestigial structures, but the thermograms obtained in the present study provide the first evidence that, in Sotalia fluviatilis, the follicles possess a well-developed sinus system, suggesting that they are part of a functional mechanosensory system. (+info)
Assessment of testicular core temperatures using microwave thermography.
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A new method for the reliable assessment of testicular core temperature using microwave technology is presented. This study was designed to assess whether alterations in testicular thermoregulation could be reliably demonstrated in patients with clinically apparent varicoceles (n = 36), in those with idiopathic male infertility (n = 52) and in fertile donors (n = 20) using this new microwave thermographic technique. The measurements obtained were found to be reliable and reproducible. Testicular core temperature measurements were significantly different between the groups (P < 0.001). Furthermore, there was a temperature gradient between the scrotal neck and the testicular core in all groups; testicular core temperatures were lower than scrotal neck temperatures. The magnitude of this temperature difference was also significantly different (P < 0.001) between the groups. Microwave testicular thermography is a new technique that is safe and accurate. Preliminary results suggest altered testicular thermoregulation in a group of patients with impaired spermatogenesis with and without varicocele. Testicular temperature profiles obtained by microwave thermography may be of value in the assessment of infertile men with or without a varicocele. (+info)