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PubMed1985

Rotational behaviour elicited by intracerebral injections of apomorphine and pergolide in 6-hydroxy-dopamine-lesioned rats. II: The striatum of the rat is heterogeneously organized for rotational behaviour.

The present study compares the role of the nucleus accumbens and the striatum, as well as various regions of the striatum, in the ability of intracerebral injections of the dopamine agonists apomorphine and pergolide to elicit rotational behaviour in 6-hydroxy-dopamine-lesioned rats. We found that apomorphine and pergolide elicit rotational behaviour when injected into the denervated striatum, but not when injected into the ipsilateral nucleus accumbens. The striatum seems heterogeneously organized as regards rotational behaviour since maximal-apomorphine rotation was elicited from the corpus of the striatum as compared to the effects produced by injections into the head and the tail of the striatum. This topographical distribution is similar to the distribution of dopamine-stimulated cyclic AMP. The pergolide response is more evenly distributed in the striatum. It is suggested that the difference in the topographical distribution of the ability of apomorphine and pergolide to elicit rotational behaviour reflects a regional distribution of dopamine receptors in the striatum of the rat.

Animals↗
PubMed1994

Glycosaminoglycans of human rotator cuff tendons: changes with age and in chronic rotator cuff tendinitis.

OBJECTIVES: To analyse the glycosaminoglycans of the adult human rotator cuff tendon matrix, to characterise changes in the glycosaminoglycan composition with age and in chronic rotator cuff tendinitis. METHODS: Rotator cuff (supraspinatus) tendons (n = 84) and common biceps tendons (n = 26) were obtained from cadavers with no history of tendon pathology (age range 11-95 years). Biopsies of rotator cuff tendons (supraspinatus and subscapularis tendons, n = 53) were obtained during open shoulder surgery to repair shoulder lesions (age range 38-80 years). Glycosaminoglycans were extracted by papain digestion and analysed by cellulose acetate electrophoresis, the carbazole assay for uronic acid and the dimethylmethylene blue dye-binding assay for sulphated glycosaminoglycans. Some digests were analysed for keratan sulphate by 5D4 monoclonal antibody ELISA. Soluble proteoglycans were extracted in 4M guanidine hydrochloride and analysed by 4-15% SDS PAGE. RESULTS: The mean (SD) sulphated glycosaminoglycan (GAG) content of the normal cadaver supraspinatus tendon was 12.3 (4.3) micrograms/mg dry weight, between three and ten times greater than in the common biceps tendon [1.2 (0.6) micrograms/mg dry weight]. The major GAG was chondroitin sulphate [6.9 (2.6) micrograms/mg dry weight], with a smaller proportion of dermatan sulphate [2.5 (1.2) micrograms/mg dry weight]. In contrast, the common biceps tendon contained predominantly dermatan sulphate [0.8 (0.2) microgram/mg dry weight] with less chondroitin sulphate [0.2 (0.2) microgram/mg dry weight]. There was no difference in the concentration of hyaluronan in these tendons [9.3 (2.8) micrograms/mg dry weight and 10.8 (4.3) micrograms/mg dry weight respectively] and there was no significant change of hyaluronan with age. Keratan sulphate was a small but significant component of the supraspinatus tendon [0.43 (0.33) microgram/mg dry weight, n = 25], whereas there was little or none in the common biceps tendon [0.04 (0.05) microgram/mg dry weight, n = 8] and there was no significant change across the age range. In the supraspinatus tendon, there was a significant decrease in total glycosaminoglycan, chondroitin sulphate and dermatan sulphate with age (p < 0.001), whether expressed relative to the tendon dry weight or total collagen content, and no change in the relative proportion of the different GAG types. There was, however, a large degree of variation within the samples. Supraspinatus tendons from patients with chronic tendinitis had a significantly increased concentration of hyaluronan [30.4 (10.1) micrograms/mg dry weight, p < 0.001], chondroitin sulphate [8.4 (1.8) micrograms/mg dry weight, p < 0.05] and dermatan sulphate [3.8 (1.1) micrograms/mg dry weight, p < 0.001] compared with normal cadaver supraspinatus tendons, although the keratan sulphate content was not significantly different [0.18 (0.05) microgram/mg dry weight]. CONCLUSIONS: The normal supraspinatus tendon has the proteoglycan/glycosaminoglycan of tendon fibrocartilage, which it is suggested is an adaptation to mechanical forces (tension, compression and shear) which act on the rotator cuff tendons in the shoulder, although other factors such as reduced vascularity, low oxygen tension and the influence of local growth factors may also be important. This functional adaptation may have important consequences for the structural strength of the supraspinatus tendon and to influence the ability of the tendon to repair after injury. The glycosaminoglycan composition of tendon specimens from patients with chronic tendinitis is consistent with acute inflammation and new matrix proteoglycan synthesis, even in relatively old tendon specimens and after at least one injection of corticosteroid.

Adolescent↗
PubMed1991

Effect of arm rotation on MR imaging of the rotator cuff.

The effect of humeral rotation on the appearance of the rotator cuff tendon in oblique coronal magnetic resonance images was evaluated in 70 such images. Internal rotation produced overlap of the supraspinatus and infraspinatus tendons with soft-tissue interposition or apparent discontinuity of the tendon in 22 cases, including 14 of 15 shoulders positioned in the first 30 degrees between extreme internal and external rotation. Imaging in internal rotation makes assessment of the tendon difficult and should be avoided.

Humans↗
PubMed1977

Maxillary rotation during human growth: annual variation and correlations with mandibular rotation. A metal implant study.

For a longitudinal study of the maxillary rotation, based on lateral headplates, a material of 22 patients with metallic implants in both jaws has been used. It has been established that the degree of maxillary rotation shows variations in direction and in intensity each year. It is smaller, in absolute value, than the degree of mandibular rotation. Due to the fact the direction of the maxillary and mandibular rotations are not always the same, it appears that the interaction between the maxillary and mandibular rotations plays an important role in the vertical and sagittal relationships of both jaws.

Adolescent↗
PubMed1977

Induction of illusory self-rotation and nystagmus by a rotating sound-field.

Subjects seated in darkness often experience illusory self-rotation when exposed to a rotating sound field. Compelling illusions of self-rotation are generally accompanied by nystagmoid movements of the eyes with the slow phase in the direction opposite that of the experienced self-rotation. These phenomena are related to the functioning of a spatial constancy mechanism by which a stable distinction is normally maintained between movements of self and movements of the environment. The appearance of nystagmus during illusory self-rotation indicates that apparent body orientation can influence oculomotor control.

Acoustic Stimulation↗
PubMed1998

Vibration-Internal Rotation-Overall Rotation Interactions in CH3OH

The zeroth order kinetic energy is developed for the vibrating-internally rotating-rotating CH3OH molecule using the general theory of Guan and Quade for large amplitude internal motion-vibration-rotation interactions in molecules. The R and T transformations are applied, respectively, to separate internal rotation from the other vibrations and overall rotation from the other vibrations in zeroth order. All zeroth order kinetic energy coefficients are calculated from the geometry and atomic masses of the CH3OH molecule. The physical significance of the two transformations is discussed in detail. This paper reports the results of the first segment of the many segments necessary in the calculations for full solution of the problem. Copyright 1998 Academic Press.

Journal Article↗
PubMedDate not supplied

Can rotational atherectomy cause thermal tissue damage? A study of the potential heating and thermal tissue effects of a rotational atherectomy device.

PURPOSE: Thermal tissue damage (TTD) is customarily associated with some lasers. The thermal potential of rotational atherectomy (RA) devices is unknown. We investigated the temperature profile and potential TTD as well as the value of fluid flushing of an RA device. METHODS: We used a high-resolution infrared imaging system that can detect changes as small as 0.1 degree C to measure the temperature changes at the tip of a fast RA device with and without fluid flushing. To assess TTD, segments of porcine aorta were subjected to the rotating tip under controlled conditions, stained by a special histochemical stain (picrisirius red) and examined under normal and polarized light microscopy. RESULTS: There was significant heating of the rotating cam. The mean "peak" temperature rise was 52.8 +/- 16.9 degrees C. This was related to rotational speed; thus the "peak" temperature rise was 88.3 +/- 12.6 degrees C at 80,000 rpm and 17.3 +/- 3.8 degrees C at 20,000 rpm (p < 0.001, t-test). Fluid flushing at 18 ml/min reduced, but did not abolish, heating of the device (11.8 +/- 2.9 degrees C). A crater was observed in all segments exposed to the rotating tip. The following features were most notable: (i) A zone of "thermal" tissue damage extended radially from the crater reaching adventitia in some sections, especially at high speeds. This zone showed markedly reduced or absent birefringence. (ii) Fluid flushing of the catheter reduced the above changes but increased the incidence and extent of dissections in the media, especially when combined with high atherectomy speeds. (iii) These changes were observed in five of six specimens exposed to RA without flushing, but in only one of six with flushing (p < 0.05). (iv) None of the above changes was seen in control segments. CONCLUSION: RA is capable of generating significant heat and potential TTD. Fluid flushing reduced heating and TTD. These findings warrant further studies in vivo, and may influence the design of atherectomy devices.

Analysis of Variance↗
PubMed1999

Macular rotation with and without counter-rotation of the globe in patients with age-related macular degeneration.

BACKGROUND: Macular rotation to treat exudative age-related macular degeneration (AMD) involves translocation of the fovea to a site with intact retinal pigment epithelium. To avoid the inevitable postoperative cyclotropia we combined this procedure with torsional muscle surgery. PATIENTS AND METHODS: In 30 eyes the macula was rotated upward by 30-50 degrees following complete artificial retinal detachment and a 360 degrees retinotomy. Simultaneous torsional muscle surgery was not carried out in the first 8 eyes; in the remaining 22 eyes surgery of the oblique muscles was performed alone or in combination with surgery of two or four rectus muscles. Simultaneously or later, muscle surgery was performed on the fellow eye in 17 of these patients. Three of the eight patients who had no primary muscle surgery were operated on later. They had muscle surgery on the macular-rotated eye and on the fellow eye. RESULTS: Postoperatively, the silicone oil was removed from all but one eye and an intraocular lens implanted in all but two eyes. Five eyes developed a postoperative retinal detachment, three of them with proliferative vitreoretinopathy. Three other eyes developed a recurrence of the choroidal neovascularization. At last examination, 18 of the 30 eyes (60%) had a near vision of 0.4 or better, sufficient for the reading of normal newsprint. Six of the eight patients who did not undergo muscle surgery reported considerable disorientation caused by the postoperative diplopia and cyclotropia. The muscle operation, which has been performed in a total of 25 patients, conferred complete freedom from complaints in all but one patient. CONCLUSION: Macular rotation succeeded in restoring reading vision in about half of cases of exudative AMD, at least in the short term. The most serious complication was the development of a retinal detachment. The extremely disorienting side effects of diplopia and tilted image could be prevented or effectively treated by muscle surgery for counter-rotation of the globe, if need be also in the fellow eye.

Aged↗
PubMed1989

Mental rotation: an event-related potential study with a validated mental rotation task.

Event-related potentials (ERPs) were recorded while subjects performed a validated mental rotation task, taken from the cognitive psychology literature. These ERPs show a late posterior negativity relative to a baseline condition requiring all of the same perceptual and cognitive processes except for the mental rotation itself. Our tentative identification of this posterior negativity with mental rotation is further supported by the finding that it varies systematically with the amount of mental rotation required on a trial by trial basis in the experimental task. We conclude that this late negativity is an ERP marker of the mental rotation process, and that this process engages primarily posterior brain regions.

Arousal↗
PubMed2004

Sex differences in mental rotation and spatial rotation in a virtual environment.

The visuospatial ability referred to as mental rotation has been shown to produce one of the largest and most consistent sex differences, in favor of males, in the cognitive literature. The current study utilizes both a paper-and-pencil version of the mental rotations test (MRT) and a virtual environment for investigating rotational ability among 44 adult subjects. Results replicate sex differences traditionally seen on paper-and-pencil measures, while no sex effects were observed in the virtual environment. These findings are discussed in terms of task demands and motor involvement. Sex differences were also seen in the patterns of correlations between rotation tasks and other neuropsychological measures. Current results suggest men may rely more on left hemisphere processing than women when engaged in rotational tasks.

Adult↗
PubMed2003

Rotation planar extraction and rotation planar chromatography of oak (Quercus robur L.) bark.

The versatile novel instrument for rotation planar extraction and rotation planar chromatography was exploited for the investigation of oak bark (Quercus robur L.). The same instrument enabled extraction of the bark, analytical proof of (+)-catechin directly in the crude extract and also its fractionation. Additionally, epimeric flavan-3-ols, (+)-catechin and (-)-epicatechin were separated by analytical ultra-micro rotation planar chromatography on cellulose plates with pure water as developing solvent. A comparison of the extraction of oak bark with 80% aqueous methanol by rotation planar extraction and medium pressure solid-liquid extraction was carried out and both techniques were shown to be suitable for the efficient extraction of oak bark. The raw extracts and fractions on thin-layer chromatography showed many compounds that possessed antioxidant activity after spraying with 1,1-diphenyl-2-picrylhydrazyl. Rotation planar fractionation of 840 mg of crude oak bark extract on silica gel gave 6.7 mg of pure (+)-catechin in one run.

Chromatography, Liquid↗
PubMed1993

13C nuclear magnetic resonance relaxation-derived psi, phi bond rotational energy barriers and rotational restrictions for glycine 13C alpha-methylenes in a GXX-repeat hexadecapeptide.

Spin-lattice relaxation of 13C multiplet spectra and [1H]-13C nuclear Overhauser enhancement (NOE) coefficients of selectively 13C-enriched glycines in a collagen GXX-repeat motif hexadecapeptide, G1VKG4DKG7NPG10WPG13APY, has been investigated. Data have been collected at two 13C Larmor frequencies (90 and 150 MHz) over the temperature range from 5 to 70 degrees C. Relaxation data indicate that the most restricted internal rotations are at G7 and G10. Mobility of other glycine residues can be arranged in the order G4, G13, and G1. G1 glycine shows that least change in motional anisotropy with temperature. Several motional models have been used to explain the experimental data. While any one model is not completely satisfactory in describing all experimental parameters, only the model of restricted internal diffusion yields the observed positive sign for the cross-correlated spectral densities. Energetic and angular limits of psi, phi bond rotational motions derived from relaxation data and the restricted diffusion model are in good agreement with those calculated as Ramachandran potentional energy profiles. G1 rotational energy barriers for overall tumbling and internal rotation are approximately equal, suggesting strong interaction between the N-terminus and water. Internal rotational parameters for GV and GG dipeptides confirm this view. Nonterminal glycine internal motions are apparently less dependent on water-peptide interactions.

Amino Acid Sequence↗
PubMed2006

Rotationally resolved optical rotation and circular dichroism effects for symmetric top molecules induced by a resonant circularly polarized pumping optical field.

The rotationally resolved laser-induced optical activity including the laser-induced optical rotation (LIOR) and laser-induced circular dichroism (LICD) effects of an IR probing light pumped by a collinear intense resonant circularly polarized light dependent on the third-order susceptibility due to the pure electric dipole interaction for achiral symmetric top molecules in the gas phase is discussed theoretically. The laser-induced optical activity contains four distinct contributions named A, B, C, and D terms: the B term of the LIOR and LICD arising from the rotational wave function perturbed by the pumping light is deduced using the semiclassical perturbation theory, and the expressions for A, C, and D terms, respectively, due to the ac Stark effect, the Boltzmann statistical redistribution, and the alteration of occupation polability, are obtained from previous results [Zheng, R.-H.; Chen, D.-M.; Wei, W.-M.; He, T.-J.; Liu, F.-C. J. Chem. Phys. 2004, 121, 6835]. The microwave-IR double resonant spectrum is proposed to detect the LIOR and LICD effects. As an example, the LIOR and LICD for the HCF(3) molecules in the conditions of 298.15 K and 0.3 Torr when the IR probing light sweeps over the rotational-vibrational transition of the v(5) and v(1) modes and the right circularly polarized microwave pumping light with the intensity of 1 kW cm(-2) at the resonant frequency 40.84 GHz are calculated on the basis of the B3LYP/6-311++G* computations. The theoretical results indicate that the B term can be of the same order of magnitude as the A and D terms, and the LIOR and LICD can be measurable in comparison to the rotationally resolved MVCD. The laser-induced optical activity may provide useful new information and form a basis for a different kind of optical activity spectroscopy.

Circular Dichroism↗
PubMed2006

Efficacy of extracorporeal shockwave lithotripsy with patients rotated supine or rotated prone for treating ureteral stones: a case-control study.

PURPOSE: To improve the therapeutic efficacy of extracorporeal shockwave lithotripsy (SWL) for ureteral stones by attempting semilateral/rotated approaches. There has been no study that shows the advantage of rotated positions. PATIENTS AND METHODS: Two hundred forty-eight (group 1) and 156 (group 1R) patients with proximal-ureteral stones were treated by the Dornier Lithotriptor U15/50 in the supine and rotated-supine position, respectively. When residual calculi remained in the middle-distal ureter, group 1 subjects underwent subsequent sessions in the ordinary prone position, and Group 1R patients were treated in the rotated-prone position. Sixty-two (group 2) and 60 (group 2R) patients with primary middle-ureteral stones were treated in the prone and rotated- prone position, respectively, while 110 (group 3) and 98 (group 3R) patients with distal-ureteral stones were treated in the prone and rotated-prone position, respectively. RESULTS: Although the stone-free rate was not different in group 1 (94.8%) and 1R (97.4%), the number of sessions required for Group 1R patients to be stonefree (mean 1.49) was less than for Group 1 patients (mean 1.74; p=0.023). Group 1R patients tolerated a higher shockwave intensity than group 1 patients for sessions in the proximal ureter (p=0.042). The stone-free rate for Groups 1 and 1R for booster sessions in the middle- distal ureter was 85.4% and 100%, respectively (p=0.059). The stone-free rate for groups 2R (95.0%) and 3R (98.0%) was higher than that for groups 2 (83.9%) and 3 (89.1%) (p=0.046; p=0.011). CONCLUSION: These effortless modifications bring about a superior outcome when treating ureteral calculi with SWL.

Adult↗
PubMed2005

3D rotational angiography: use of propeller rotation for the evaluation of intracranial aneurysms.

We compared two methods of 3D digital subtraction angiography (DSA)--propeller and standard rotation--for the assessment of aneurysmal morphology and its relation to neighboring vessels. Aneurysms were correctly visualized and localized with both techniques. 3D DSA with propeller rotation technique seems to be effective and allows us to reduce the amount of contrast material related to a shortened acquisition time. Technical progress including propeller rotation allows a larger range of rotation and faster rotational speeds.

Adolescent↗
PubMed1996

MR imaging of rotator cuff impingement: correlation with full-thickness rotator cuff tear.

BACKGROUND: Rotator cuff tears usually derive from shoulder impingement, and need surgical treatment. This study is to verify the Magnetic Resonance Image (MRI) findings of rotator cuff impingement which are related to full-thickness rotate cuff tear (FTRCT). METHODS: Totally 68 patients with shoulder impingement syndrome were studied, including 39 shoulders with surgically-proven FTRCT, and 29 shoulders without FTRCT. MRI findings of shoulder impingement were evaluated for peribursal fat plane, subacromial distance, acromion shape, subacromioclavicular space, irregularity of coracoacromial ligament and presence of subacromial spurs. The correlation with FTRCT was also determined. RESULTS: Peribursal fat plane obliteration (p = 0.0001), hook-shaped acromion (p = 0.0148), subacromioclavicular indentation (p = 0.0004), and decreased subacromial distance (p = 0.0005) showed significant correlation with FTRCT; however, subacromial spurs (p = 0.6238) and thickened irregular coracoacromial ligament (p = 0.1611) showed poor correlation. CONCLUSIONS: Specific MRI findings of rotator cuff impingement are fairly reliable and helpful for discrimination of FTRCT from non-FTRCT cases, and can be used preoperatively and noninvasively to determine the necessity of surgical repair of rotator cuff.

Adult↗
PubMed1998

Change from slowly rotating 8-hour shifts to rapidly rotating 8-hour and 12-hour shifts using participative shift roster design.

OBJECTIVES: The study examined the impact of change, from slowly rotating continuous 8-hour shifts to more rapidly rotating continuous 8-hour and 12-hour shifts, on the health and quality of life of shift workers. METHODS: Self-report survey data were collected from 72 shift workers at 3 sewage treatment plants before and several months after roster change. After the change 1 plant first worked a rapidly rotating, 8-hour shift roster and then worked a 12-hour shift roster, and the other 2 plants worked continuous 12-hour shift rosters. RESULTS: After the change the shift workers at each plant reported increased satisfaction with roster design, a decrease in physical and psychological circadian malaise associated with shift work, improved day sleep quality, less tiredness, and improvements in the quality of home, social and work life. A between-plant comparison of the rapidly rotating 8-hour and 12-hour shift rosters showed greater improvements had been obtained with the 12-hour shift roster, and no significant differences in tiredness or sleep quality between the redesigned 8- and 12-hour shift rosters. However, a within-plant matched-pairs comparison at the 1st plant of the rapidly rotating 8-hour shift roster and the 12-hour shift roster showed no significant differences. CONCLUSIONS: The results show that the prior level of support for change may best explain the impact of roster redesign on individual well-being. They lend further support to shift worker participation in roster design.

Adult↗
PubMed1994

MR arthrographic depiction of tears of the rotator cuff: benefit of abduction and external rotation of the arm.

PURPOSE: To show the effectiveness of positioning the arm in abduction and external rotation (ABER) during magnetic resonance (MR) arthrography for depiction of tears of the rotator cuff. MATERIALS AND METHODS: Five throwing athletes with shoulder pain were prospectively imaged with standard MR imaging, MR arthrography, and ABER MR arthrography. The status of the rotator cuff was recorded; arthroscopic correlation was obtained. RESULTS: One partial tear of the distal infraspinatus tendon was detected with ABER MR arthrography only. One full-thickness tear was detected with both MR arthrography and ABER MR arthrography, but the component of the tear that extended into the infraspinatus tendon was depicted with ABER MR arthrography only. One partial tear was detected with both MR arthrography and ABER MR arthrography; no additional information was provided by either technique alone. CONCLUSION: The ABER position may be useful in detection and characterization of tears of the rotator cuff, especially partial tears of the undersurface. This information would be useful in selection of patients for conservative therapy, arthroscopy, or arthrotomy.

Adult↗