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Sample records for circadian wrist activity

  1. Disturbances in the circadian pattern of activity and sleep after laparoscopic versus open abdominal surgery

    DEFF Research Database (Denmark)

    Gögenur, Ismail; Bisgaard, Thue; Burgdorf, Stefan;

    2008-01-01

    BACKGROUND: Studies on the circadian variation in bodily functions and sleep are important for understanding the pathophysiological processes in the postoperative period. We aimed to investigate changes in the circadian variation in activity after minimally invasive surgery (laparoscopic cholecys......BACKGROUND: Studies on the circadian variation in bodily functions and sleep are important for understanding the pathophysiological processes in the postoperative period. We aimed to investigate changes in the circadian variation in activity after minimally invasive surgery (laparoscopic...... scale (sleep quality, general well-being and pain) and fatigue was measured by a ten-point fatigue scale. The activity levels of the patients were monitored by actigraphy (a wrist-worn device measuring patient activity). Measures of circadian activity level [interday stability (IS), intraday variability...... circadian activity parameters (IS, IV and AMP). CONCLUSION: Severely disturbed circadian activity parameters was found after both LC and MAS with worse changes after MAS. Measures of circadian activity pattern analyses correlated significantly with postoperative subjective recovery parameters....

  2. Mirror therapy in a patient with a fractured wrist and no active wrist extension.

    Science.gov (United States)

    Altschuler, Eric L; Hu, Jeong

    2008-01-01

    We report a patient in whom mirror therapy, training moving both hands while watching the reflection of the present or good hand in a parasaggital mirror - a method used for phantom limb and stroke patients - was extremely useful after a fractured wrist with good passive, but no active, extension. PMID:18335358

  3. Machine learning for activity recognition: hip versus wrist data

    International Nuclear Information System (INIS)

    Problem addressed: Wrist-worn accelerometers are associated with greater compliance. However, validated algorithms for predicting activity type from wrist-worn accelerometer data are lacking. This study compared the activity recognition rates of an activity classifier trained on acceleration signal collected on the wrist and hip. Methodology: 52 children and adolescents (mean age 13.7  ±  3.1 year) completed 12 activity trials that were categorized into 7 activity classes: lying down, sitting, standing, walking, running, basketball, and dancing. During each trial, participants wore an ActiGraph GT3X+ tri-axial accelerometer on the right hip and the non-dominant wrist. Features were extracted from 10-s windows and inputted into a regularized logistic regression model using R (Glmnet + L1). Results: Classification accuracy for the hip and wrist was 91.0% ± 3.1% and 88.4% ± 3.0%, respectively. The hip model exhibited excellent classification accuracy for sitting (91.3%), standing (95.8%), walking (95.8%), and running (96.8%); acceptable classification accuracy for lying down (88.3%) and basketball (81.9%); and modest accuracy for dance (64.1%). The wrist model exhibited excellent classification accuracy for sitting (93.0%), standing (91.7%), and walking (95.8%); acceptable classification accuracy for basketball (86.0%); and modest accuracy for running (78.8%), lying down (74.6%) and dance (69.4%). Potential Impact: Both the hip and wrist algorithms achieved acceptable classification accuracy, allowing researchers to use either placement for activity recognition. (paper)

  4. The circadian rest-activity rhythm, a potential safety pharmacology endpoint of cancer chemotherapy.

    Science.gov (United States)

    Ortiz-Tudela, Elisabet; Iurisci, Ida; Beau, Jacques; Karaboue, Abdoulaye; Moreau, Thierry; Rol, Maria Angeles; Madrid, Juan Antonio; Lévi, Francis; Innominato, Pasquale F

    2014-06-01

    The robustness of the circadian timing system (CTS) was correlated to quality of life and predicted for improved survival in cancer patients. However, chemotherapy disrupted the CTS according to dose and circadian timing in mice. A continuous and repeated measures longitudinal design was implemented here to characterize CTS dynamics in patients receiving a fixed circadian-based chemotherapy protocol. The rest-activity rhythm of 49 patients with advanced cancer was monitored using a wrist actigraph for 13 days split into four consecutive spans of 3-4 days each, i.e., before, during, right after and late after a fixed chronotherapy course. The relative amount of activity in bed vs. out of bed (Ihr amplitude (Amp), interdaily stability (IS) and intradaily variability (IV) were compared according to study span. Circadian disruption (Iimprovement (14.3%); alteration and complete recovery (31%) or sustained deterioration (45%), possibly due to inadequate chronotherapy dosing and/or timing. Improved clinical tolerability could result from the minimization of circadian disruption through the personalization of chronotherapy delivery. PMID:24510611

  5. Marker placement to describe the wrist movements during activities of daily living in cyclical tasks

    NARCIS (Netherlands)

    Murgia, A; Kyberd, PJ; Chappell, PH; Light, CM

    2004-01-01

    Objective. To describe the wrist kinematics during movement through free range of motion and activities of daily living using a cyclical task. Design. The wrist angles were initially calculated in a calibration trial and then in two selected activities of daily living (jar opening and carton pouring

  6. Wrist pain

    Science.gov (United States)

    Pain - wrist; Pain - carpal tunnel; Injury - wrist; Arthritis - wrist; Gout - wrist; Pseudogout - wrist ... Carpal tunnel syndrome: A common cause of wrist pain is carpal tunnel syndrome . You may feel aching, ...

  7. Real-time magnetic resonance imaging (MRI during active wrist motion--initial observations.

    Directory of Open Access Journals (Sweden)

    Robert D Boutin

    Full Text Available BACKGROUND: Non-invasive imaging techniques such as magnetic resonance imaging (MRI provide the ability to evaluate the complex anatomy of bone and soft tissues of the wrist without the use of ionizing radiation. Dynamic instability of wrist--occurring during joint motion--is a complex condition that has assumed increased importance in musculoskeletal medicine. The objective of this study was to develop an MRI protocol for evaluating the wrist during continuous active motion, to show that dynamic imaging of the wrist is realizable, and to demonstrate that the resulting anatomical images enable the measurement of metrics commonly evaluated for dynamic wrist instability. METHODS: A 3-Tesla "active-MRI" protocol was developed using a bSSFP sequence with 475 ms temporal resolution for continuous imaging of the moving wrist. Fifteen wrists of 10 asymptomatic volunteers were scanned during active supination/pronation, radial/ulnar deviation, "clenched-fist", and volarflexion/dorsiflexion maneuvers. Two physicians evaluated distal radioulnar joint (DRUJ congruity, extensor carpi ulnaris (ECU tendon translation, the scapholunate (SL interval, and the SL, radiolunate (RL and capitolunate (CL angles from the resulting images. RESULTS: The mean DRUJ subluxation ratio was 0.04 in supination, 0.10 in neutral, and 0.14 in pronation. The ECU tendon was subluxated or translated out of its groove in 3 wrists in pronation, 9 wrists in neutral, and 11 wrists in supination. The mean SL interval was 1.43 mm for neutral, ulnar deviation, radial deviation positions, and increased to 1.64 mm during the clenched-fist maneuver. Measurement of SL, RL and CL angles in neutral and dorsiflexion was also accomplished. CONCLUSION: This study demonstrates the initial performance of active-MRI, which may be useful in the investigation of dynamic wrist instability in vivo.

  8. 78 FR 36307 - Proposed Information Collection (Wrist Conditions Disability Benefits Questionnaire) Activity...

    Science.gov (United States)

    2013-06-17

    ... AFFAIRS Proposed Information Collection (Wrist Conditions Disability Benefits Questionnaire) Activity... . Please refer to ``OMB Control No. 2900-NEW (Wrist Conditions Disability Benefits Questionnaire)'' in any... Conditions Disability Benefits Questionnaire, VA Form 21-0960M-16. OMB Control Number: 2900-NEW...

  9. 78 FR 36643 - Proposed Information Collection (Wrist Conditions Disability Benefits Questionnaire) Activity...

    Science.gov (United States)

    2013-06-18

    ... AFFAIRS Proposed Information Collection (Wrist Conditions Disability Benefits Questionnaire) Activity... . Please refer to ``OMB Control No. 2900--NEW (Wrist Conditions Disability Benefits Questionnaire)'' in any... Conditions Disability Benefits Questionnaire, VA Form 21-0960M-16. OMB Control Number: 2900-NEW...

  10. The transcription factor DBP affects circadian sleep consolidation and rhythmic EEG activity

    OpenAIRE

    Franken, Paulus; Lopez Molina, Luis; Marcacci, Lysiane; Schibler, Ulrich; Tafti, Mehdi

    2000-01-01

    Albumin D-binding protein (DBP) is a PAR leucine zipper transcription factor that is expressed according to a robust circadian rhythm in the suprachiasmatic nuclei, harboring the circadian master clock, and in most peripheral tissues. Mice lacking DBP display a shorter circadian period in locomotor activity and are less active. Thus, although DBP is not essential for circadian rhythm generation, it does modulate important clock outputs. We studied the role of DBP in the circadian and homeosta...

  11. The calcineurin-NFAT pathway controls activity-dependent circadian gene expression in slow skeletal muscle

    OpenAIRE

    Dyar, Kenneth A.; Stefano Ciciliot; Guidantonio Malagoli Tagliazucchi; Giorgia Pallafacchina; Jana Tothova; Carla Argentini; Lisa Agatea; Reimar Abraham; Miika Ahdesmäki; Mattia Forcato; Silvio Bicciato; Stefano Schiaffino; Bert Blaauw

    2015-01-01

    Objective: Physical activity and circadian rhythms are well-established determinants of human health and disease, but the relationship between muscle activity and the circadian regulation of muscle genes is a relatively new area of research. It is unknown whether muscle activity and muscle clock rhythms are coupled together, nor whether activity rhythms can drive circadian gene expression in skeletal muscle. Methods: We compared the circadian transcriptomes of two mouse hindlimb muscles wi...

  12. Hippocampal activity mediates the relationship between circadian activity rhythms and memory in older adults.

    Science.gov (United States)

    Sherman, Stephanie M; Mumford, Jeanette A; Schnyer, David M

    2015-08-01

    Older adults experience parallel changes in sleep, circadian rhythms, and episodic memory. These processes appear to be linked such that disruptions in sleep contribute to deficits in memory. Although more variability in circadian patterns is a common feature of aging and predicts pathology, little is known about how alterations in circadian activity rhythms within older adults influence new episodic learning. Following 10 days of recording sleep-wake patterns using actigraphy, healthy older adults underwent fMRI while performing an associative memory task. The results revealed better associative memory was related to more consistent circadian activity rhythms, independent of total sleep time, sleep efficiency, and level of physical activity. Moreover, hippocampal activity during successful memory retrieval events was positively correlated with associative memory accuracy and circadian activity rhythm (CAR) consistency. We demonstrated that the link between consistent rhythms and associative memory performance was mediated by hippocampal activity. These findings provide novel insight into how the circadian rhythm of sleep-wake cycles are associated with memory in older adults and encourage further examination of circadian activity rhythms as a biomarker of cognitive functioning. PMID:26205911

  13. Circadian pattern and burstiness in human communication activity

    CERN Document Server

    Jo, Hang-Hyun; Kertész, János; Kaski, Kimmo

    2011-01-01

    The temporal pattern of human communication is inhomogeneous and bursty, as reflected by the heavy tail distribution of the inter-event times. For the origin of this behavior two main mechanisms have been suggested: a) Externally driven inhomogeneities due to the circadian and weekly activity patterns and b) intrinsic correlation based inhomogeneity rooted deeply in the task handling strategies of humans. Here we address this question by providing systematic de-seasoning methods to remove the circadian and weekly patterns from the time series of communication events. We find that the heavy tails of the inter-event time distributions are robust with respect to this procedure indicating that burstiness is mostly caused by the latter mechanism b). Moreover, we find that our de-seasoning procedure improves the scaling behavior of the distribution.

  14. Separating bedtime rest from activity using waist or wrist-worn accelerometers in youth.

    Directory of Open Access Journals (Sweden)

    Dustin J Tracy

    Full Text Available Recent interest in sedentary behavior and technological advances expanded use of watch-size accelerometers for continuous monitoring of physical activity (PA over extended periods (e.g., 24 h/day for 1 week in studies conducted in natural living environment. This approach necessitates the development of new methods separating bedtime rest and activity periods from the accelerometer recordings. The goal of this study was to develop a decision tree with acceptable accuracy for separating bedtime rest from activity in youth using accelerometer placed on waist or wrist. Minute-by-minute accelerometry data were collected from 81 youth (10-18 years old, 47 females during a monitored 24-h stay in a whole-room indirect calorimeter equipped with a force platform covering the floor to detect movement. Receiver Operating Characteristic (ROC curve analysis was used to determine the accelerometer cut points for rest and activity. To examine the classification differences, the accelerometer bedtime rest and activity classified by the algorithm in the development group (n = 41 were compared with actual bedtime rest and activity classification obtained from the room calorimeter-measured metabolic rate and movement data. The selected optimal bedtime rest cut points were 20 and 250 counts/min for the waist- and the wrist-worn accelerometer, respectively. The selected optimal activity cut points were 500 and 3,000 counts/min for waist and wrist-worn accelerometers, respectively. Bedtime rest and activity were correctly classified by the algorithm in the validation group (n = 40 by both waist- (sensitivity: 0.983, specificity: 0.946, area under ROC curve: 0. 872 and wrist-worn (0.999, 0.980 and 0.943 accelerometers. The decision tree classified bedtime rest correctly with higher accuracy than commonly used automated algorithm for both waist- and wrist-warn accelerometer (all p<0.001. We concluded that cut points developed and validated for waist- and wrist

  15. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors.

    Science.gov (United States)

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J M

    2016-01-01

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such as smoking, eating, drinking coffee and giving a talk. To recognize such activities, wrist-worn motion sensors are used. However, these two positions are mainly used in isolation. To use richer context information, we evaluate three motion sensors (accelerometer, gyroscope and linear acceleration sensor) at both wrist and pocket positions. Using three classifiers, we show that the combination of these two positions outperforms the wrist position alone, mainly at smaller segmentation windows. Another problem is that less-repetitive activities, such as smoking, eating, giving a talk and drinking coffee, cannot be recognized easily at smaller segmentation windows unlike repetitive activities, like walking, jogging and biking. For this purpose, we evaluate the effect of seven window sizes (2-30 s) on thirteen activities and show how increasing window size affects these various activities in different ways. We also propose various optimizations to further improve the recognition of these activities. For reproducibility, we make our dataset publicly available. PMID:27023543

  16. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors

    Science.gov (United States)

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J. M.

    2016-01-01

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such as smoking, eating, drinking coffee and giving a talk. To recognize such activities, wrist-worn motion sensors are used. However, these two positions are mainly used in isolation. To use richer context information, we evaluate three motion sensors (accelerometer, gyroscope and linear acceleration sensor) at both wrist and pocket positions. Using three classifiers, we show that the combination of these two positions outperforms the wrist position alone, mainly at smaller segmentation windows. Another problem is that less-repetitive activities, such as smoking, eating, giving a talk and drinking coffee, cannot be recognized easily at smaller segmentation windows unlike repetitive activities, like walking, jogging and biking. For this purpose, we evaluate the effect of seven window sizes (2–30 s) on thirteen activities and show how increasing window size affects these various activities in different ways. We also propose various optimizations to further improve the recognition of these activities. For reproducibility, we make our dataset publicly available. PMID:27023543

  17. A role for Drosophila ATX2 in activation of PER translation and circadian behavior.

    Science.gov (United States)

    Zhang, Yong; Ling, Jinli; Yuan, Chunyan; Dubruille, Raphaëlle; Emery, Patrick

    2013-05-17

    A negative transcriptional feedback loop generates circadian rhythms in Drosophila. PERIOD (PER) is a critical state-variable in this mechanism, and its abundance is tightly regulated. We found that the Drosophila homolog of ATAXIN-2 (ATX2)--an RNA-binding protein implicated in human neurodegenerative diseases--was required for circadian locomotor behavior. ATX2 was necessary for PER accumulation in circadian pacemaker neurons and thus determined period length of circadian behavior. ATX2 was required for the function of TWENTY-FOUR (TYF), a crucial activator of PER translation. ATX2 formed a complex with TYF and promoted its interaction with polyadenylate-binding protein (PABP). Our work uncovers a role for ATX2 in circadian timing and reveals that this protein functions as an activator of PER translation in circadian neurons. PMID:23687048

  18. Scoring of synovial membrane hypertrophy and bone erosions by MR imaging in clinically active and inactive rheumatoid arthritis of the wrist

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Gideon, P; Sørensen, K;

    1995-01-01

    MRI-scores of synovial membrane hypertrophy and bone erosions of the RA-wrist are introduced. Gadolinium-DTPA enhanced magnetic resonance imaging (MRI) and conventional radiography (CR) of the wrist were performed in 16 patients with rheumatoid arthritis (RA) and 3 healthy controls. A MRI-score of...... MRI and CR with respect to bone erosions. Bone erosions were detected by MRI in 14 wrists in contrast to only 6 wrists by CR. In all patients the erosions were more numerous on MRI. The introduced methods may be useful quantitative measures of synovitis and early joint destruction in RA....... synovial membrane hypertrophy was obtained by summation of gradings of synovial hypertrophy in 6 regions of the wrist. The score was significantly higher in wrists with than in wrists without clinical signs of active arthritis. The score was 0 in all healthy controls. Each bone of the wrist was assessed by...

  19. Indirect wrist MR arthrography: the effects of passive motion versus active exercise

    International Nuclear Information System (INIS)

    Purpose. In the wrist, to determine whether passive motion or active exercise yields a better indirect MR arthrographic effect following intravenous gadolinium administration.Design and patients. Twenty-six consecutive patients were studied by indirect wrist MR arthrography. In half active exercise and in half passive motion was performed. Four regions of interest were studied including the distal radioulnar joint, the radiocarpal joint, the midcarpal joint, and the triangular fibrocartilage. Ranges and means of signal intensity were calculated. Surgical follow-up was performed in 22 patients.Results. The joint fluid intensity was greatest in the distal radioulnar joint. Fluid signal intensity was greater and more consistent in the passive motion group although the results did not achieve statistical significance. Imaging accuracy appeared similar in the two groups and was excellent for the triangular fibrocartilage (100%) and scapholunate ligaments (96%).Conclusion. Active exercise and passive motion yield similar degrees of wrist arthrographic effect, but the effect of passive motion is somewhat more consistent. Preliminary data show good accuracy for internal derangements. (orig.)

  20. Wrist pain

    Science.gov (United States)

    ... the wrist that allows feeling and movement to parts of the hand. Swelling can occur if you: Do repetitive movements with your wrist, such as typing on a computer keyboard, using a computer mouse, playing racquetball or ...

  1. Circadian rhythms of temperature and activity in obese and lean Zucker rats

    Science.gov (United States)

    Murakami, D. M.; Horwitz, B. A.; Fuller, C. A.

    1995-01-01

    The circadian timing system is important in the regulation of feeding and metabolism, both of which are aberrant in the obese Zucker rat. This study tested the hypothesis that these abnormalities involve a deficit in circadian regulation by examining the circadian rhythms of body temperature and activity in lean and obese Zucker rats exposed to normal light-dark cycles, constant light, and constant dark. Significant deficits in both daily mean and circadian amplitude of temperature and activity were found in obese Zucker female rats relative to lean controls in all lighting conditions. However, the circadian period of obese Zucker rats did not exhibit differences relative to lean controls in either of the constant lighting conditions. These results indicate that although the circadian regulation of temperature and activity in obese Zucker female rats is in fact depressed, obese rats do exhibit normal entrainment and pacemaker functions in the circadian timing system. The results suggest a deficit in the process that generates the amplitude of the circadian rhythm.

  2. Chronic hyperammonemia alters the circadian rhythms of corticosteroid hormone levels and of motor activity in rats.

    Science.gov (United States)

    Ahabrach, Hanan; Piedrafita, Blanca; Ayad, Abdelmalik; El Mlili, Nisrin; Errami, Mohammed; Felipo, Vicente; Llansola, Marta

    2010-05-15

    Patients with liver cirrhosis may present hepatic encephalopathy with a wide range of neurological disturbances and alterations in sleep quality and in the sleep-wake circadian rhythm. Hyperammonemia is a main contributor to the neurological alterations in hepatic encephalopathy. We have assessed, in an animal model of chronic hyperammonemia without liver failure, the effects of hyperammonemia per se on the circadian rhythms of motor activity, temperature, and plasma levels of adrenal corticosteroid hormones. Chronic hyperammonemia alters the circadian rhythms of locomotor activity and of cortisol and corticosterone levels in blood. Different types of motor activity are affected differentially. Hyperammonemia significantly alters the rhythm of spontaneous ambulatory activity, reducing strongly ambulatory counts and slightly average velocity during the night (the active phase) but not during the day, resulting in altered circadian rhythms. In contrast, hyperammonemia did not affect wheel running at all, indicating that it affects spontaneous but not voluntary activity. Vertical activity was affected only very slightly, indicating that hyperammonemia does not induce anxiety. Hyperammonemia abolished completely the circadian rhythm of corticosteroid hormones in plasma, completely eliminating the peaks of cortisol and corticosterone present in control rats at the start of the dark period. The data reported show that chronic hyperammonemia, similar to that present in patients with liver cirrhosis, alters the circadian rhythms of corticosteroid hormones and of motor activity. This suggests that hyperammonemia would be a relevant contributor to the alterations in corticosteroid hormones and in circadian rhythms in patients with liver cirrhosis. PMID:19998493

  3. A random forest classifier for the prediction of energy expenditure and type of physical activity from wrist and hip accelerometers

    International Nuclear Information System (INIS)

    Wrist accelerometers are being used in population level surveillance of physical activity (PA) but more research is needed to evaluate their validity for correctly classifying types of PA behavior and predicting energy expenditure (EE). In this study we compare accelerometers worn on the wrist and hip, and the added value of heart rate (HR) data, for predicting PA type and EE using machine learning. Forty adults performed locomotion and household activities in a lab setting while wearing three ActiGraph GT3X+ accelerometers (left hip, right hip, non-dominant wrist) and a HR monitor (Polar RS400). Participants also wore a portable indirect calorimeter (COSMED K4b2), from which EE and metabolic equivalents (METs) were computed for each minute. We developed two predictive models: a random forest classifier to predict activity type and a random forest of regression trees to estimate METs. Predictions were evaluated using leave-one-user-out cross-validation. The hip accelerometer obtained an average accuracy of 92.3% in predicting four activity types (household, stairs, walking, running), while the wrist accelerometer obtained an average accuracy of 87.5%. Across all 8 activities combined (laundry, window washing, dusting, dishes, sweeping, stairs, walking, running), the hip and wrist accelerometers obtained average accuracies of 70.2% and 80.2% respectively. Predicting METs using the hip or wrist devices alone obtained root mean square errors (rMSE) of 1.09 and 1.00 METs per 6 min bout, respectively. Including HR data improved MET estimation, but did not significantly improve activity type classification. These results demonstrate the validity of random forest classification and regression forests for PA type and MET prediction using accelerometers. The wrist accelerometer proved more useful in predicting activities with significant arm movement, while the hip accelerometer was superior for predicting locomotion and estimating EE. (paper)

  4. Circadian period integrates network information through activation of the BMP signaling pathway.

    Directory of Open Access Journals (Sweden)

    Esteban J Beckwith

    2013-12-01

    Full Text Available Living organisms use biological clocks to maintain their internal temporal order and anticipate daily environmental changes. In Drosophila, circadian regulation of locomotor behavior is controlled by ∼150 neurons; among them, neurons expressing the PIGMENT DISPERSING FACTOR (PDF set the period of locomotor behavior under free-running conditions. To date, it remains unclear how individual circadian clusters integrate their activity to assemble a distinctive behavioral output. Here we show that the BONE MORPHOGENETIC PROTEIN (BMP signaling pathway plays a crucial role in setting the circadian period in PDF neurons in the adult brain. Acute deregulation of BMP signaling causes period lengthening through regulation of dClock transcription, providing evidence for a novel function of this pathway in the adult brain. We propose that coherence in the circadian network arises from integration in PDF neurons of both the pace of the cell-autonomous molecular clock and information derived from circadian-relevant neurons through release of BMP ligands.

  5. Circadian Period Integrates Network Information Through Activation of the BMP Signaling Pathway

    Science.gov (United States)

    Beckwith, Esteban J.; Gorostiza, E. Axel; Berni, Jimena; Rezával, Carolina; Pérez-Santángelo, Agustín; Nadra, Alejandro D.; Ceriani, María Fernanda

    2013-01-01

    Living organisms use biological clocks to maintain their internal temporal order and anticipate daily environmental changes. In Drosophila, circadian regulation of locomotor behavior is controlled by ∼150 neurons; among them, neurons expressing the PIGMENT DISPERSING FACTOR (PDF) set the period of locomotor behavior under free-running conditions. To date, it remains unclear how individual circadian clusters integrate their activity to assemble a distinctive behavioral output. Here we show that the BONE MORPHOGENETIC PROTEIN (BMP) signaling pathway plays a crucial role in setting the circadian period in PDF neurons in the adult brain. Acute deregulation of BMP signaling causes period lengthening through regulation of dClock transcription, providing evidence for a novel function of this pathway in the adult brain. We propose that coherence in the circadian network arises from integration in PDF neurons of both the pace of the cell-autonomous molecular clock and information derived from circadian-relevant neurons through release of BMP ligands. PMID:24339749

  6. The human endogenous circadian system causes greatest platelet activation during the biological morning independent of behaviors.

    Directory of Open Access Journals (Sweden)

    Frank A J L Scheer

    Full Text Available BACKGROUND: Platelets are involved in the thromboses that are central to myocardial infarctions and ischemic strokes. Such adverse cardiovascular events have day/night patterns with peaks in the morning (~9 AM, potentially related to endogenous circadian clock control of platelet activation. The objective was to test if the human endogenous circadian system influences (1 platelet function and (2 platelet response to standardized behavioral stressors. We also aimed to compare the magnitude of any effects on platelet function caused by the circadian system with that caused by varied standardized behavioral stressors, including mental arithmetic, passive postural tilt and mild cycling exercise. METHODOLOGY/PRINCIPAL FINDINGS: We studied 12 healthy adults (6 female who lived in individual laboratory suites in dim light for 240 h, with all behaviors scheduled on a 20-h recurring cycle to permit assessment of endogenous circadian function independent from environmental and behavioral effects including the sleep/wake cycle. Circadian phase was assessed from core body temperature. There were highly significant endogenous circadian rhythms in platelet surface activated glycoprotein (GP IIb-IIIa, GPIb and P-selectin (6-17% peak-trough amplitudes; p ≤ 0.01. These circadian peaks occurred at a circadian phase corresponding to 8-9 AM. Platelet count, ATP release, aggregability, and plasma epinephrine also had significant circadian rhythms but with later peaks (corresponding to 3-8 PM. The circadian effects on the platelet activation markers were always larger than that of any of the three behavioral stressors. CONCLUSIONS/SIGNIFICANCE: These data demonstrate robust effects of the endogenous circadian system on platelet activation in humans--independent of the sleep/wake cycle, other behavioral influences and the environment. The 9 AM timing of the circadian peaks of the three platelet surface markers, including platelet surface activated GPIIb-IIIa, the

  7. Effects of chronic administration and withdrawal of antidepressant agents on circadian activity rhythms in rats.

    Science.gov (United States)

    Wollnik, F

    1992-10-01

    Experimental and clinical studies indicate that clinical depression may be associated with disturbances of circadian rhythms. To explore the interaction between circadian rhythmicity, behavioral state, and monoaminergic systems, the present study investigated the effects of chronic administration and withdrawal of the following antidepressant agents on circadian wheel-running rhythms of laboratory rats: a) moclobemide, a reversible and selective monoamine oxidase (MAO) type A inhibitor; b) Ro 19-6327, a selective MAO type B inhibitor; c) desipramine, a preferential norepinephrine reuptake inhibitor; d) clomipramine and e) fluoxetine, both serotonin reuptake inhibitors; and f) levoprotiline, an atypical antidepressant whose biochemical mechanism is still unknown. Wheel-running activity rhythms were studied in three inbred strains of laboratory rats (ACI, BH, LEW) under constant darkness (DD). Two of these inbred strains (BH and LEW) show profound abnormalities in their circadian activity rhythms, namely, a reduced overall level of activity and bimodal or multimodal activity patterns. Chronic treatment with moclobemide and desipramine consistently increased the overall level, as well as the circadian amplitude, of the activity rhythm. Furthermore, the abnormal activity pattern of the LEW strain was changed into a unimodal activity pattern like that of other laboratory rats. The free-running period tau was slightly shortened by moclobemide and dramatically shortened by desipramine. Effects of moclobemide and desipramine treatment on overall activity level and duration were reversed shortly after termination of treatment, whereas long aftereffects were observed for the free-running period. All other substances tested had no systematic effects on the activity rhythms of any of the strains. The fact that moclobemide and desipramine altered the period, amplitude, and pattern of circadian activity rhythms is consistent with the hypothesis that monoaminergic transmitters

  8. Wrist actigraphy for scratch detection in the presence of confounding activities.

    Science.gov (United States)

    Feuerstein, Johanna; Austin, Daniel; Sack, Robert; Hayes, Tamara L

    2011-01-01

    Scratching is a symptom of many dermatological disorders, especially atopic dermatitis. For the development of anti-itch medications, there is a need for objective measures of scratching. Wrist actigraphy (monitoring wrist and hand movements with micro-accelerometers) is a promising method for assessing scratching; however, currently available technology has a limited capacity to discriminate scratching from other similar movements. In this study, we investigated methods to improve the specificity of actigraphy for scratch detection on movement data collected from subjects using the PAM-RL actigraph. A k-means cluster analysis was used to differentiate scratching from walking and restless sleep, which are potential confounds for nighttime scratching. Features used in the analysis include variance, peak frequency, autocorrelation value at one lag, and number of counts above 0.01 g's. The k-means cluster analysis exhibited a high sensitivity (0.90 ± 0.10) and specificity for walking (0.98 ± 0.05) and restless sleep (0.88 ± 0.06), respectively, demonstrating the separability of these activities. This work indicates that the features described here can be used to develop a classifier that discriminates scratch from other activities. The described method of scratch detection shows promise as an objective method for assessing scratching movements in clinical trials and longitudinal studies of scratch. PMID:22255131

  9. Individual variation in circadian rhythms of sleep, EEG, temperature, and activity among monkeys - Implications for regulatory mechanisms.

    Science.gov (United States)

    Crowley, T. J.; Halberg, F.; Kripke, D. F.; Pegram, G. V.

    1971-01-01

    Investigation of circadian rhythms in a number of variables related to sleep, EEG, temperature, and motor activity in rhesus monkeys on an LD 12:12 schedule. Circadian rhythms were found to appear in each of 15 variables investigated. Statistical procedures assessed the variables for evidence of common regulation in these aspects of their circadian rhythms: acrophase (timing), amplitude (extent of change), and level (24-hr mean value). Patterns appearing in the data suggested that the circadian rhythms of certain variables are regulated in common. The circadian modulation of activity in the beta and sigma frequency bands of the EEG was correlated with statistical significance in acrophase, level, and amplitude. The delta frequency band appeared to be under circadian rhythm regulation distinct from that of the other bands. The circadian rhythm of REM stage sleep was like that of beta activity in level and amplitude. The data indicate that REM stage may share some common regulation of circadian timing with both stage 3-4 sleep and with temperature. Generally, however, the circadian rhythm of temperature appeared to bear little relation to the circadian rhythms of motor activity, EEG, or sleep.

  10. Intermonitor reliability of the GT3X+ accelerometer at hip, wrist and ankle sites during activities of daily living

    International Nuclear Information System (INIS)

    The triaxial GT3X+ accelerometer can measure activity counts in the vertical, horizontal right to left, horizontal front to back planes, and can generate a summative score of the three axes represented by vector magnitude (VM). Information on the reliability of the GT3X+ at the hip, wrist and ankle sites, over all axes and VM during activities of daily living (ADL) is lacking in the literature. Forty healthy adults (14 men and 26 women) were randomly assigned to perform 10 of 20 ADL (consisting of sedentary, housework, yard work, locomotive and recreational activities) while wearing two monitors on the hip, wrist and ankle. Subjects performed each ADL over 7 min and the mean activity counts during the last 4 min were used for analyses. Average intraclass correlations between monitors were high for the three sites for each axis and VM (hip: 0.943, 0.857, 0.864 and 0.966, respectively; wrist: 0.994, 0.963, 0.961 and 0.989, respectively; ankle: 0.977, 0.979, 0.927 and 0.986, respectively). These data suggest that GT3X+ accelerometers measurements made from the hip, wrist and ankle sites are reliable during ADL across all axes and VM. (paper)

  11. Different effects of age, adiposity and physical activity on the risk of ankle, wrist and hip fractures in postmenopausal women.

    Science.gov (United States)

    Armstrong, Miranda E G; Cairns, Benjamin J; Banks, Emily; Green, Jane; Reeves, Gillian K; Beral, Valerie

    2012-06-01

    While increasing age, decreasing body mass index (BMI), and physical inactivity are known to increase hip fracture risk, whether these factors have similar effects on other common fractures is not well established. We used prospectively-collected data from a large cohort to examine the role of these factors on the risk of incident ankle, wrist and hip fractures in postmenopausal women. 1,155,304 postmenopausal participants in the Million Women Study with a mean age of 56.0 (SD 4.8) years, provided information about lifestyle, anthropometric, and reproductive factors at recruitment in 1996-2001. All participants were linked to National Health Service cause-specific hospital records for day-case or overnight admissions. During follow-up for an average of 8.3 years per woman, 6807 women had an incident ankle fracture, 9733 an incident wrist fracture, and 5267 an incident hip fracture. Adjusted absolute and relative risks (RRs) for incident ankle, wrist, and hip fractures were calculated using Cox regression models. Age-specific rates for wrist and hip fractures increased sharply with age, whereas rates for ankle fracture did not. Cumulative absolute risks from ages 50 to 84 years per 100 women were 2.5 (95%CI 2.2-2.8) for ankle fracture, 5.0 (95%CI 4.4-5.5) for wrist fracture, and 6.2 (95%CI 5.5-7.0) for hip fracture. Compared with lean women (BMI<20 kg/m(2)), obese women (BMI≥30 kg/m(2)) had a three-fold increased risk of ankle fracture (RR=3.07; 95%CI 2.53-3.74), but a substantially reduced risk of wrist fracture and especially of hip fracture (RR=0.57; 0.51-0.64 and 0.23; 0.21-0.27, respectively). Physical activity was associated with a reduced risk of hip fracture but was not associated with ankle or wrist fracture risk. Ankle, wrist and hip fractures are extremely common in postmenopausal women, but the associations with age, adiposity, and physical activity differ substantially between the three fracture sites. PMID:22465850

  12. [Factors Affecting the Dynamics of Circadian Activity of Frit Flies Meromyza saltatrix (L) (Diptera: Chloropidae)].

    Science.gov (United States)

    Safonkin, A F; Triselyova, T A; Yazchuk, A A; Akent'eva, N A

    2015-01-01

    The dynamics of circadian activity in adult frit flies of the Holarctic species Meromyza saltatrix (L) from Mongolian, Moscow, and Polish populations was studied. Synchronous peaks of activity were revealed with the periodicity multiple of three-four hours, which may depend on the level of light. The direct effect of temperature and humidity on the activity of flies outside the optimal values of these factors was found. It was detected that the peak of adult emergence falls on the beginning of a general increase in the abundance of flies, which indicates constant rejuvenation of the population. The sex ratio is close to 1, but the emergence of males and females is in antiphase. The synchronization of peaks of circadian activity in the populations from different regions confirms the presence of a circadian rhythm of activity. The rhythm synchronizing the reproductive activity of adults was found to be modified by the photoperiod under the optimum conditions of temperature and humidity. PMID:26852486

  13. Pharmacological modulation of circadian rhythms by synthetic activators of the deacetylase SIRT1

    Science.gov (United States)

    Bellet, Marina M.; Nakahata, Yasukazu; Boudjelal, Mohamed; Watts, Emma; Mossakowska, Danuta E.; Edwards, Kenneth A.; Cervantes, Marlene; Astarita, Giuseppe; Loh, Christine; Ellis, James L.; Vlasuk, George P.; Sassone-Corsi, Paolo

    2013-01-01

    Circadian rhythms govern a wide variety of physiological and metabolic functions in many organisms, from prokaryotes to humans. We previously reported that silent information regulator 1 (SIRT1), a NAD+-dependent deacetylase, contributes to circadian control. In addition, SIRT1 activity is regulated in a cyclic manner in virtue of the circadian oscillation of the coenzyme NAD+. Here we used specific SIRT1 activator compounds both in vitro and in vivo. We tested a variety of compounds to show that the activation of SIRT1 alters CLOCK:BMAL1-driven transcription in different systems. Activation of SIRT1 induces repression of circadian gene expression and decreases H3 K9/K14 acetylation at corresponding promoters in a time-specific manner. Specific activation of SIRT1 was demonstrated in vivo using liver-specific SIRT1-deficient mice, where the effect of SIRT1 activator compounds was shown to be dependent on SIRT1. Our findings demonstrate that SIRT1 can fine-tune circadian rhythm and pave the way to the development of pharmacological strategies to address a broad range of therapeutic indications. PMID:23341587

  14. Sympathetic Activation Induces Skeletal Fgf23 Expression in a Circadian Rhythm-dependent Manner*

    Science.gov (United States)

    Kawai, Masanobu; Kinoshita, Saori; Shimba, Shigeki; Ozono, Keiichi; Michigami, Toshimi

    2014-01-01

    The circadian clock network is well known to link food intake and metabolic outputs. Phosphorus is a pivotal nutritional factor involved in energy and skeletal metabolisms and possesses a circadian profile in the circulation; however, the precise mechanisms whereby phosphate metabolism is regulated by the circadian clock network remain largely unknown. Because sympathetic tone, which displays a circadian profile, is activated by food intake, we tested the hypothesis that phosphate metabolism was regulated by the circadian clock network through the modification of food intake-associated sympathetic activation. Skeletal Fgf23 expression showed higher expression during the dark phase (DP) associated with elevated circulating FGF23 levels and enhanced phosphate excretion in the urine. The peaks in skeletal Fgf23 expression and urine epinephrine levels, a marker for sympathetic tone, shifted from DP to the light phase (LP) when mice were fed during LP. Interestingly, β-adrenergic agonist, isoproterenol (ISO), induced skeletal Fgf23 expression when administered at ZT12, but this was not observed in Bmal1-deficient mice. In vitro reporter assays revealed that ISO trans-activated Fgf23 promoter through a cAMP responsive element in osteoblastic UMR-106 cells. The mechanism of circadian regulation of Fgf23 induction by ISO in vivo was partly explained by the suppressive effect of Cryptochrome1 (Cry1) on ISO signaling. These results indicate that the regulation of skeletal Fgf23 expression by sympathetic activity is dependent on the circadian clock system and may shed light on new regulatory networks of FGF23 that could be important for understanding the physiology of phosphate metabolism. PMID:24302726

  15. Circadian motor activity affected by stimulant medication in children with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Ironside, Sarah; Davidson, Fiona; Corkum, Penny

    2010-12-01

    Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent disorder occurring in approximately 3-5% of school-aged children. The core symptoms of ADHD are effectively treated with stimulant medications such as methylphenidate; however, there are also negative side effects, including insomnia. It has been suggested that administration of stimulant medication may alter the timing or regularity of circadian motor activity levels. This study aimed to investigate the impact of stimulant medication on the strength and timing of circadian rhythms in 16 stimulant medication-naïve children with ADHD. Participants were monitored for changes in motor activity during a 3-week blinded placebo-controlled medication trial to examine the impact of immediate-release methylphenidate hydrochloride. Motor activity was measured by actigraphy, and 24-h activity profiles were analysed using cosinor analyses to identify measurable changes in circadian rhythms. The children in this sample demonstrated significant increases in motor activity during the sleep-onset latency period. They also showed a significant reduction in relative circadian amplitude and a phase-delay in the timing of the daily rhythm. Clinicians and parents of children being treated with stimulant medication for ADHD should be aware that stimulant medication may cause disruption of sleep/circadian rhythms. Behavioural strategies to improve sleep may be useful for children experiencing these negative effects from medication. PMID:20629940

  16. Impaired release of corticosterone from adrenals contributes to impairment of circadian rhythms of activity in hyperammonemic rats.

    Science.gov (United States)

    Llansola, Marta; Ahabrach, Hanan; Errami, Mohammed; Cabrera-Pastor, Andrea; Addaoudi, Kaoutar; Felipo, Vicente

    2013-08-15

    Patients with liver cirrhosis may present impaired sleep-wake and circadian rhythms, relative adrenal insufficiency and altered hypothalamus-pituitary-adrenal gland (HPA) axis. The underlying mechanisms remain unclear. Circadian rhythms are modulated by corticosteroids which secretion is regulated by HPA axis. Hyperammonemia alters circadian rhythms of activity and corticosterone in rats. The aims were: (1) assessing whether corticosterone alterations are responsible for altered circadian rhythm in hyperammonemia: (2) to shed light on the mechanism by which corticosterone circadian rhythm is altered in hyperammonemia. The effects of daily corticosterone injection at ZT10 on circadian rhythms of activity, plasma corticosterone, adreno-corticotropic hormone (ACTH) and hypothalamic corticotropic releasing hormone (CRH) were assessed in control and hyperammonemic rats. ACTH-induced corticosterone release was analyzed in cultured adrenal cells. Corticosterone injection restores the corticosterone peak in hyperammonemic rats and their activity and circadian rhythm. Plasma ACTH and CRH in hypothalamus are increased in hyperammonemic rats. Corticosterone injection normalizes ACTH. Chronic hyperammonemia impairs adrenal function, reduces corticosterone content and ACTH-induced corticosterone release in adrenals, leading to reduced feedback modulation of HPA axis by corticosterone which contributes to impair circadian rhythms of activity. Impaired circadian rhythms and motor activity may be corrected in hyperammonemia and hepatic encephalopathy by corticosterone treatment. PMID:23376587

  17. Number of Days Required to Estimate Habitual Activity Using Wrist-Worn GENEActiv Accelerometer: A Cross-Sectional Study

    OpenAIRE

    Dillon, Christina B.; Fitzgerald, Anthony P.; Kearney, Patricia M.; Perry, Ivan J; Rennie, Kirsten L.; Kozarski, Robert; Phillips, Catherine M.

    2016-01-01

    Introduction Objective methods like accelerometers are feasible for large studies and may quantify variability in day-to-day physical activity better than self-report. The variability between days suggests that day of the week cannot be ignored in the design and analysis of physical activity studies. The purpose of this paper is to investigate the optimal number of days needed to obtain reliable estimates of weekly habitual physical activity using the wrist-worn GENEActiv accelerometer. Metho...

  18. Physical activity profiling: Activity-specific step counting and energy expenditure models using 3D wrist acceleration.

    Science.gov (United States)

    Delgado-Gonzalo, R; Celka, P; Renevey, Ph; Dasen, S; Sola, J; Bertschi, M; Lemay, M

    2015-08-01

    In this paper, we present the evaluation of a new physical activity profiling system embedded in a wrist-located device. We propose a step counting and an energy expenditure (EE) method, and evaluate their accuracy against gold standard references. To this end, we used an actimetry sensor on the waist and an indirect calorimetry monitoring device on a population of 13 subjects to obtain step count and metabolic equivalent task (kcal/kg/h) referenced values. The subjects followed a protocol that spanned a given set of activities (lying, standing, walking, running) at a wide range of intensities. The performance of the EE model was characterized by a root-mean-square error (RMSE) of 1.22±0.34kcal/min, and step-count model at regular walking/running speeds by 0.71±0.06step/10sec. PMID:26738171

  19. Attenuated food anticipatory activity and abnormal circadian locomotor rhythms in Rgs16 knockdown mice.

    Directory of Open Access Journals (Sweden)

    Naoto Hayasaka

    Full Text Available Regulators of G protein signaling (RGS are a multi-functional protein family, which functions in part as GTPase-activating proteins (GAPs of G protein α-subunits to terminate G protein signaling. Previous studies have demonstrated that the Rgs16 transcripts exhibit robust circadian rhythms both in the suprachiasmatic nucleus (SCN, the master circadian light-entrainable oscillator (LEO of the hypothalamus, and in the liver. To investigate the role of RGS16 in the circadian clock in vivo, we generated two independent transgenic mouse lines using lentiviral vectors expressing short hairpin RNA (shRNA targeting the Rgs16 mRNA. The knockdown mice demonstrated significantly shorter free-running period of locomotor activity rhythms and reduced total activity as compared to the wild-type siblings. In addition, when feeding was restricted during the daytime, food-entrainable oscillator (FEO-driven elevated food-anticipatory activity (FAA observed prior to the scheduled feeding time was significantly attenuated in the knockdown mice. Whereas the restricted feeding phase-advanced the rhythmic expression of the Per2 clock gene in liver and thalamus in the wild-type animals, the above phase shift was not observed in the knockdown mice. This is the first in vivo demonstration that a common regulator of G protein signaling is involved in the two separate, but interactive circadian timing systems, LEO and FEO. The present study also suggests that liver and/or thalamus regulate the food-entrained circadian behavior through G protein-mediated signal transduction pathway(s.

  20. A Simple Complex Case: Restoration of Circadian Cortisol Activity

    Directory of Open Access Journals (Sweden)

    Ragini C Bhake

    2015-08-01

    Full Text Available A 38-year-old librarian with confirmed Carney complex (PRKAR1a mutation was referred for further evaluation of ACTH-independent Cushing's syndrome. Previously, she was known to have schwannoma (excised, adenomyoepithelioma and normal annual echocardiograms. Over three years prior to current presentation, she had become aware of coarse hair on her chin and abdomen, as well as centripetal weight gain. She had noticed subtle but definite reduction in her girdle muscle strength. She had acquired some mood changes atypical of her personality, and had developed an interrupted sleep pattern. To our knowledge, this is the first published report of circadian RU486 therapy for PPNAD in a patient with Carney complex. It may have been possible to restore low levels surrounding the midnight hours using other agents, but the side-effect profile and lack of significantly elevated levels of cortisol made them less favorable options.

  1. Circadian activity rhythm of the house fly continues after optic tract severance and lobectomy

    OpenAIRE

    Helfrich, Charlotte; Cymborowski, Bronislaw; Engelmann, Wolfgang

    1985-01-01

    Under constant conditions, locomotor activity in about 50% of 63 adult Musca domestica continued to be rhythmic after bilateral severance of optic tracts or bilateral lobectomy. Apparently, the optic lobes of Musca do not contain the oscillator for rhythmic control of locomotor activity as has been proposed for other insects. In 20% of the individuals, several circadian components of activity rhythms were found after operation indicating a role of the optic lobes in the coupling of oscillator...

  2. 78 FR 44625 - Proposed Information Collection (Wrist Conditions Disability Benefits Questionnaire) Activity...

    Science.gov (United States)

    2013-07-24

    ... 17, 2013 (78 FR 36307), inviting the public to comment on a proposed information collection titled ``Wrist Conditions Disability Benefits Questionnaire, VA Form 21-0960M-16.'' On June 18, 2013 (78 FR 36643... corrects that error by withdrawing the FR notice that published on June 18, 2013 (FR Doc 2013-14412)....

  3. ATAXIN-2 activates PERIOD translation to sustain circadian rhythms in Drosophila.

    Science.gov (United States)

    Lim, Chunghun; Allada, Ravi

    2013-05-17

    Evidence for transcriptional feedback in circadian timekeeping is abundant, yet little is known about the mechanisms underlying translational control. We found that ATAXIN-2 (ATX2), an RNA-associated protein involved in neurodegenerative disease, is a translational activator of the rate-limiting clock component PERIOD (PER) in Drosophila. ATX2 specifically interacted with TWENTY-FOUR (TYF), an activator of PER translation. RNA interference-mediated depletion of Atx2 or the expression of a mutant ATX2 protein that does not associate with polyadenylate-binding protein (PABP) suppressed behavioral rhythms and decreased abundance of PER. Although ATX2 can repress translation, depletion of Atx2 from Drosophila S2 cells inhibited translational activation by RNA-tethered TYF and disrupted the association between TYF and PABP. Thus, ATX2 coordinates an active translation complex important for PER expression and circadian rhythms. PMID:23687047

  4. Integrating Circadian Activity and Gene Expression Profiles to Predict Chronotoxicity of Drosophila suzukii Response to Insecticides

    OpenAIRE

    Hamby, Kelly A.; Kwok, Rosanna S.; Frank G. Zalom; Chiu, Joanna C.

    2013-01-01

    Native to Southeast Asia, Drosophila suzukii (Matsumura) is a recent invader that infests intact ripe and ripening fruit, leading to significant crop losses in the U.S., Canada, and Europe. Since current D. suzukii management strategies rely heavily on insecticide usage and insecticide detoxification gene expression is under circadian regulation in the closely related Drosophila melanogaster, we set out to determine if integrative analysis of daily activity patterns and detoxification gene ex...

  5. Robust heart rate estimation using wrist-based PPG signals in the presence of intense physical activities.

    Science.gov (United States)

    Chengzhi Zong; Jafari, Roozbeh

    2015-08-01

    Heart rate tracking from a wrist-type photoplethysmogram (PPG) signal during intensive physical activities is a challenge that is attracting more attention thanks to the introduction of wrist-worn wearable computers. Commonly-used motion artifact rejection methods coupled with simple periodicity-based heart rate estimation techniques are incapable of achieving satisfactory heart rate tracking performance during intense activities. In this paper, we propose a two-stage solution. Firstly, we introduce an improved spectral subtraction method to reject the spectral components of motion artifacts. Secondly, instead of using heuristic mechanisms, we formalize the spectral peaks selection process as the shortest path search problem and validate its effectiveness. Analysis on the experimental results based on a published database shows that: (1) Our proposed method outperforms three other comparable methods with regards to heart rate estimation error. (2) The proposed method is a promising candidate for both offline cardiac health analysis and online heart rate tracking in daily life, even during intensive physical motions. PMID:26738168

  6. Positioning Commercial Pedometers to Measure Activity of Older Adults with Slow Gait: At the Wrist or at the Waist?

    Science.gov (United States)

    Ehrler, Frederic; Weber, Chloe; Lovis, Christian

    2016-01-01

    Sedentary behaviour is a major risk factor for chronic disease morbidity and mortality in aging. Measuring people activity through devices such as pedometers is a recognized intervention to motivate them for more physical activity. However, the feedback provided by these devices must be accurate in order to avoid overtraining and keep users' motivation alive. If the accuracy of pedometers has been validated for healthy people, their lack of accuracy for elderly people walking at slower pace has been reported in several studies. The emergence on the consumer's market of new devices that can be worn indifferently at the wrist or at the waist raises once more this concern. In order to evaluate whether pedometers' location influences their accuracy, we have tested three pedometers at different locations, and for several paces in a comparative study. Beyond confirming the decrease of pedometers' accuracy with speed reduction, our study reveals that pedometers should be worn at the waist rather than at the wrist. This leads us to recommend wearing pedometers at the waist when monitoring population with reduced mobility. PMID:27071868

  7. Adaptation of sleep and circadian rhythms to the Antarctic summer - A question of zeitgeber strength

    Science.gov (United States)

    Gander, Philippa H.; Macdonald, John A.; Montgomery, John C.; Paulin, Michael G.

    1991-01-01

    Adaptation of sleep and circadian rhythms was examined in three temperate zone dwellers arriving in Antarctica during summer. Rectal temperature, wrist activity, and heart rate were monitored continuously, sleep timing and quality noted on awakening, and mood and fatigue rated every 2 h while awake. Sleep was poorer in 2/3 subjects in Antarctica, where all subjects reported more difficulty rising. Sleep occurred at the same clock times in New Zealand and Antarctica, however, the rhythms of temperature, activity, and heart rate underwent a delay of about of 2 h. The subject with the most Antarctic experience had the least difficulty adapting to sleeping during constant daylight. The subject with the most delayed circadian rhythms had the most difficulty. The delay in the circadian system with respect to sleep and clock time is hypothesized to be due to differences in zeitgeber strength and/or zeitgeber exposure between Antarctica and New Zealand.

  8. Integrating circadian activity and gene expression profiles to predict chronotoxicity of Drosophila suzukii response to insecticides.

    Science.gov (United States)

    Hamby, Kelly A; Kwok, Rosanna S; Zalom, Frank G; Chiu, Joanna C

    2013-01-01

    Native to Southeast Asia, Drosophila suzukii (Matsumura) is a recent invader that infests intact ripe and ripening fruit, leading to significant crop losses in the U.S., Canada, and Europe. Since current D. suzukii management strategies rely heavily on insecticide usage and insecticide detoxification gene expression is under circadian regulation in the closely related Drosophila melanogaster, we set out to determine if integrative analysis of daily activity patterns and detoxification gene expression can predict chronotoxicity of D. suzukii to insecticides. Locomotor assays were performed under conditions that approximate a typical summer or winter day in Watsonville, California, where D. suzukii was first detected in North America. As expected, daily activity patterns of D. suzukii appeared quite different between 'summer' and 'winter' conditions due to differences in photoperiod and temperature. In the 'summer', D. suzukii assumed a more bimodal activity pattern, with maximum activity occurring at dawn and dusk. In the 'winter', activity was unimodal and restricted to the warmest part of the circadian cycle. Expression analysis of six detoxification genes and acute contact bioassays were performed at multiple circadian times, but only in conditions approximating Watsonville summer, the cropping season, when most insecticide applications occur. Five of the genes tested exhibited rhythmic expression, with the majority showing peak expression at dawn (ZT0, 6am). We observed significant differences in the chronotoxicity of D. suzukii towards malathion, with highest susceptibility at ZT0 (6am), corresponding to peak expression of cytochrome P450s that may be involved in bioactivation of malathion. High activity levels were not found to correlate with high insecticide susceptibility as initially hypothesized. Chronobiology and chronotoxicity of D. suzukii provide valuable insights for monitoring and control efforts, because insect activity as well as insecticide timing

  9. Trends in Wrist Arthroscopy

    Science.gov (United States)

    Obdeijn, Miryam C.; Tuijthof, Gabrielle J. M.; van der Horst, Chantal M. A. M.; Mathoulin, Christophe; Liverneaux, Philippe

    2013-01-01

    Background Wrist arthroscopy plays a role in both the diagnosis and the treatment of wrist pathology. It has evolved in the last three decades. Questions The present status of wrist arthroscopy was investigated by answering the following questions: -What is its current position in the treatment wrist pathologies according to the literature? -What is its current position according to hand surgeons? Methods Analysis of the number of publications on wrist arthroscopy was performed and compared with the number of publications on other arthroscopy topics to assess the current position of wrist arthroscopy. The members of the EWAS (European Wrist Arthroscopy Society) and the members of eight national hand surgery societies were questioned on wrist arthroscopy in daily practice. Results From 1975 till now, 925 papers on wrist arthroscopy were found. The publications on wrist arthroscopy increased from an average of 8/year (1986) to 26/year (2012). More than half (56.9%) of the respondents of the EWAS perform fewer than 5 wrist arthroscopies per month, and only 7 (10.8%) indicate the performance of more than 10 wrist arthroscopies per month. Seventy-four percent of the orthopedic hand surgeons perform wrist arthroscopy (in 48.5% for therapeutic indications) against 36.8% of plastic surgery hand surgeons (in 23.1% for therapeutic indications). Conclusion Wrist arthroscopy has taken up a place in the armamentarium of the hand surgeon. The place of wrist arthroscopy in daily practice is related to the background of the hand surgeon. PMID:24436823

  10. Retinal rhythms in chicks: circadian variation in melantonin and serotonin N-acetyltransferase activity.

    OpenAIRE

    Hamm, H E; Menaker, M

    1980-01-01

    There is a large-amplitude circadian rhythm of indoleamine metabolism in the retina-pigment epithelium of the chicken. N-Acetyltransferase activity (arylamine acetyltransferase; acetyl-CoA:arylamine N-acetyltransferase, EC 2.3.1.5) and melatonin content are 15-fold higher at night than during the day in a cycle of a 4-fold increase during the subjective night. Light at midnight inactivates N-acetyltransferase and lowers melatonin. N-Acetyltransferase activity is found predominantly in the ret...

  11. Ngram time series model to predict activity type and energy cost from wrist, hip and ankle accelerometers: implications of age

    Science.gov (United States)

    Strath, Scott J; Kate, Rohit J; Keenan, Kevin G; Welch, Whitney A; Swartz, Ann M

    2016-01-01

    To develop and test time series single site and multi-site placement models, we used wrist, hip and ankle processed accelerometer data to estimate energy cost and type of physical activity in adults. Ninety-nine subjects in three age groups (18–39, 40–64, 65 + years) performed 11 activities while wearing three triaxial accelereometers: one each on the non-dominant wrist, hip, and ankle. During each activity net oxygen cost (METs) was assessed. The time series of accelerometer signals were represented in terms of uniformly discretized values called bins. Support Vector Machine was used for activity classification with bins and every pair of bins used as features. Bagged decision tree regression was used for net metabolic cost prediction. To evaluate model performance we employed the jackknife leave-one-out cross validation method. Single accelerometer and multi-accelerometer site model estimates across and within age group revealed similar accuracy, with a bias range of −0.03 to 0.01 METs, bias percent of −0.8 to 0.3%, and a rMSE range of 0.81–1.04 METs. Multi-site accelerometer location models improved activity type classification over single site location models from a low of 69.3% to a maximum of 92.8% accuracy. For each accelerometer site location model, or combined site location model, percent accuracy classification decreased as a function of age group, or when young age groups models were generalized to older age groups. Specific age group models on average performed better than when all age groups were combined. A time series computation show promising results for predicting energy cost and activity type. Differences in prediction across age group, a lack of generalizability across age groups, and that age group specific models perform better than when all ages are combined needs to be considered as analytic calibration procedures to detect energy cost and type are further developed. PMID:26449155

  12. Ngram time series model to predict activity type and energy cost from wrist, hip and ankle accelerometers: implications of age.

    Science.gov (United States)

    Strath, Scott J; Kate, Rohit J; Keenan, Kevin G; Welch, Whitney A; Swartz, Ann M

    2015-11-01

    To develop and test time series single site and multi-site placement models, we used wrist, hip and ankle processed accelerometer data to estimate energy cost and type of physical activity in adults. Ninety-nine subjects in three age groups (18-39, 40-64, 65 +  years) performed 11 activities while wearing three triaxial accelereometers: one each on the non-dominant wrist, hip, and ankle. During each activity net oxygen cost (METs) was assessed. The time series of accelerometer signals were represented in terms of uniformly discretized values called bins. Support Vector Machine was used for activity classification with bins and every pair of bins used as features. Bagged decision tree regression was used for net metabolic cost prediction. To evaluate model performance we employed the jackknife leave-one-out cross validation method. Single accelerometer and multi-accelerometer site model estimates across and within age group revealed similar accuracy, with a bias range of -0.03 to 0.01 METs, bias percent of -0.8 to 0.3%, and a rMSE range of 0.81-1.04 METs. Multi-site accelerometer location models improved activity type classification over single site location models from a low of 69.3% to a maximum of 92.8% accuracy. For each accelerometer site location model, or combined site location model, percent accuracy classification decreased as a function of age group, or when young age groups models were generalized to older age groups. Specific age group models on average performed better than when all age groups were combined. A time series computation show promising results for predicting energy cost and activity type. Differences in prediction across age group, a lack of generalizability across age groups, and that age group specific models perform better than when all ages are combined needs to be considered as analytic calibration procedures to detect energy cost and type are further developed. PMID:26449155

  13. Circadian activity rhythm in pre-pubertal and pubertal marmosets (Callithrix jacchus) living in family groups.

    Science.gov (United States)

    Melo, Paula R; Gonçalves, Bruno S B; Menezes, Alexandre A L; Azevedo, Carolina V M

    2016-03-01

    In marmosets, a phase advance was observed in activity onset in pubertal animals living in captivity under semi-natural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂ and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythm in marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm. PMID:26724713

  14. A circadian clock in the olfactory bulb anticipates feeding during food anticipatory activity.

    Directory of Open Access Journals (Sweden)

    Nahum Nolasco

    Full Text Available Rabbit pups ingest food, in this case milk, once a day with circadian periodicity and are a natural model of food anticipatory activity. During nursing, several sensory systems receive information about properties of the food, one of them being the olfactory system, which has received little attention in relation to synchronization by food. In addition, the olfactory bulb has a circadian pacemaker that exhibits rhythms independently of the suprachiasmatic nucleus, but the biological functions of these rhythms are largely unknown. In the present contribution, we hypothesized that circadian suckling of milk synchronizes rhythms in the olfactory bulb. To this aim we explored by immunohistochemistry, rhythms of FOS and PER1 proteins, as indicators of activation and reporter of oscillations, respectively, through a complete 24-h cycle in periglomerular, mitral and granular cell layers of both the main and the accessory olfactory bulb. Subjects were 7-day-old rabbit pups scheduled to nurse during the night (02:00 h or day (10:00 h, and also fasted subjects, to explore the possible persistence of oscillations. In the three layers of the main olfactory bulb, FOS was high at time of nursing, then further increased 1.5 h afterward, and then decreased to increase again in advance of the next nursing bout. This pattern persisted, without the postprandial increase, in fasted subjects with a shift in subjects nursed at 02:00. PER1 was increased 2-8 h after nursing and this increase persisted in most cell layers, with a shift, in fasted subjects. In the accessory olfactory bulb we only observed a consistent pattern of FOS expression in the mitral cell layer of nursed subjects, similar to that of the main olfactory bulb. We conclude that the main olfactory bulb is synchronized during milk ingestion, but during fasting its oscillations perhaps are modulated by the suprachiasmatic nucleus, as proposed for rodents.

  15. Chronotype influences activity circadian rhythm and sleep: differences in sleep quality between weekdays and weekend.

    Science.gov (United States)

    Vitale, Jacopo A; Roveda, Eliana; Montaruli, Angela; Galasso, Letizia; Weydahl, Andi; Caumo, Andrea; Carandente, Franca

    2015-04-01

    Several studies have shown the differences among chronotypes in the circadian rhythm of different physiological variables. Individuals show variation in their preference for the daily timing of activity; additionally, there is an association between chronotype and sleep duration/sleep complaints. Few studies have investigated sleep quality during the week days and weekends in relation to the circadian typology using self-assessment questionnaires or actigraphy. The purpose of this study was to use actigraphy to assess the relationship between the three chronotypes and the circadian rhythm of activity levels and to determine whether sleep parameters respond differently with respect to time (weekdays versus the weekend) in Morning-types (M-types), Neither-types (N-types) and Evening-types (E-types). The morningness-eveningness questionnaire (MEQ) was administered to 502 college students to determine their chronotypes. Fifty subjects (16 M-types, 15 N-types and 19 E-types) were recruited to undergo a 7-days monitoring period with an actigraph (Actiwacth® actometers, CNT, Cambridge, UK) to evaluate their sleep parameters and the circadian rhythm of their activity levels. To compare the amplitude and the acrophase among the three chronotypes, we used a one-way ANOVA followed by the Tukey-Kramer post-hoc test. To compare the Midline Estimating Statistic of Rhythm (MESOR) among the three chronotypes, we used a Kruskal-Wallis non-parametric test followed by pairwise comparisons that were performed using Dunn's procedure with a Bonferroni correction for multiple comparisons. The analysis of each sleep parameter was conducted using the mixed ANOVA procedure. The results showed that the chronotype was influenced by sex (χ(2) with p = 0.011) and the photoperiod at birth (χ(2) with p reduced sleep quality and quantity compared with the M- and N-types during weekdays, whereas the E-types reached the same levels as the other chronotypes during the weekends. These

  16. Peripheral CLOCK regulates target-tissue glucocorticoid receptor transcriptional activity in a circadian fashion in man.

    Directory of Open Access Journals (Sweden)

    Evangelia Charmandari

    Full Text Available CONTEXT AND OBJECTIVE: Circulating cortisol fluctuates diurnally under the control of the "master" circadian CLOCK, while the peripheral "slave" counterpart of the latter regulates the transcriptional activity of the glucocorticoid receptor (GR at local glucocorticoid target tissues through acetylation. In this manuscript, we studied the effect of CLOCK-mediated GR acetylation on the sensitivity of peripheral tissues to glucocorticoids in humans. DESIGN AND PARTICIPANTS: We examined GR acetylation and mRNA expression of GR, CLOCK-related and glucocorticoid-responsive genes in peripheral blood mononuclear cells (PBMCs obtained at 8 am and 8 pm from 10 healthy subjects, as well as in PBMCs obtained in the morning and cultured for 24 hours with exposure to 3-hour hydrocortisone pulses every 6 hours. We used EBV-transformed lymphocytes (EBVLs as non-synchronized controls. RESULTS: GR acetylation was higher in the morning than in the evening in PBMCs, mirroring the fluctuations of circulating cortisol in reverse phase. All known glucocorticoid-responsive genes tested responded as expected to hydrocortisone in non-synchronized EBVLs, however, some of these genes did not show the expected diurnal mRNA fluctuations in PBMCs in vivo. Instead, their mRNA oscillated in a Clock- and a GR acetylation-dependent fashion in naturally synchronized PBMCs cultured ex vivo in the absence of the endogenous glucocorticoid, suggesting that circulating cortisol might prevent circadian GR acetylation-dependent effects in some glucocorticoid-responsive genes in vivo. CONCLUSIONS: Peripheral CLOCK-mediated circadian acetylation of the human GR may function as a target-tissue, gene-specific counter regulatory mechanism to the actions of diurnally fluctuating cortisol, effectively decreasing tissue sensitivity to glucocorticoids in the morning and increasing it at night.

  17. Circadian Rhythms

    Science.gov (United States)

    ... body function and health? Circadian rhythms can influence sleep-wake cycles, hormone release, body temperature and other important bodily functions. They have been linked to various sleep disorders, such as insomnia. Abnormal circadian rhythms have also ...

  18. Wrist pulse (image)

    Science.gov (United States)

    To measure the pulse at the wrist, place the index and middle finger over the underside of the opposite wrist, below the base ... firmly with flat fingers until you feel the pulse in the radial artery.

  19. Arthritis of the Wrist

    Science.gov (United States)

    ... in the hand and wrist. It is symmetrical, meaning that it usually affects the same joint on ... swelling, pain, limited motion, and weakness. However, in contrast to OA, wrist symptoms will usually be accompanied ...

  20. Repeated Episodes of Heroin Cause Enduring Alterations of Circadian Activity in Protracted Abstinence

    Directory of Open Access Journals (Sweden)

    Luis Stinus

    2012-09-01

    Full Text Available Opiate withdrawal is followed by a protracted abstinence syndrome consisting of craving and physiological changes. However, few studies have been dedicated to both the characterization and understanding of these long-term alterations in post-dependent subjects. The aim of the present study was to develop an opiate dependence model, which induces long-lasting behavioral changes in abstinent rats. Here, we first compared the effects of several protocols for the induction of opiate dependence (morphine pellets, repeated morphine or heroin injections on the subsequent response to heroin challenges (0.25 mg/kg at different time points during abstinence (3, 6, 9 and 18 weeks. In a second set of experiments, rats were exposed to increasing doses of heroin and subsequently monitored for general circadian activity up to 20 weeks of abstinence. Results show that heroin injections rather than the other methods of opiate administration have long-term consequences on rats’ sensitivity to heroin with its psychostimulant effects persisting up to 18 weeks of abstinence. Moreover, intermittent episodes of heroin dependence rather than a single exposure produce enduring alteration of the basal circadian activity both upon heroin cessation and protracted abstinence. Altogether, these findings suggest that the induction of heroin dependence through intermittent increasing heroin injections is the optimal method to model long-term behavioral alterations during protracted abstinence in rats. This animal model would be useful in further characterizing long-lasting changes in post-dependent subjects to help understand the prolonged vulnerability to relapse.

  1. Repeated episodes of heroin cause enduring alterations of circadian activity in protracted abstinence.

    Science.gov (United States)

    Stinus, Luis; Cador, Martine; Caille, Stephanie

    2012-01-01

    Opiate withdrawal is followed by a protracted abstinence syndrome consisting of craving and physiological changes. However, few studies have been dedicated to both the characterization and understanding of these long-term alterations in post-dependent subjects. The aim of the present study was to develop an opiate dependence model, which induces long-lasting behavioral changes in abstinent rats. Here, we first compared the effects of several protocols for the induction of opiate dependence (morphine pellets, repeated morphine or heroin injections) on the subsequent response to heroin challenges (0.25 mg/kg) at different time points during abstinence (3, 6, 9 and 18 weeks). In a second set of experiments, rats were exposed to increasing doses of heroin and subsequently monitored for general circadian activity up to 20 weeks of abstinence. Results show that heroin injections rather than the other methods of opiate administration have long-term consequences on rats' sensitivity to heroin with its psychostimulant effects persisting up to 18 weeks of abstinence. Moreover, intermittent episodes of heroin dependence rather than a single exposure produce enduring alteration of the basal circadian activity both upon heroin cessation and protracted abstinence. Altogether, these findings suggest that the induction of heroin dependence through intermittent increasing heroin injections is the optimal method to model long-term behavioral alterations during protracted abstinence in rats. This animal model would be useful in further characterizing long-lasting changes in post-dependent subjects to help understand the prolonged vulnerability to relapse. PMID:24961201

  2. Neural activity in the suprachiasmatic circadian clock of nocturnal mice anticipating a daytime meal.

    Science.gov (United States)

    Dattolo, T; Coomans, C P; van Diepen, H C; Patton, D F; Power, S; Antle, M C; Meijer, J H; Mistlberger, R E

    2016-02-19

    Circadian rhythms in mammals are regulated by a system of circadian oscillators that includes a light-entrainable pacemaker in the suprachiasmatic nucleus (SCN) and food-entrainable oscillators (FEOs) elsewhere in the brain and body. In nocturnal rodents, the SCN promotes sleep in the day and wake at night, while FEOs promote an active state in anticipation of a predictable daily meal. For nocturnal animals to anticipate a daytime meal, wake-promoting signals from FEOs must compete with sleep-promoting signals from the SCN pacemaker. One hypothesis is that FEOs impose a daily rhythm of inhibition on SCN output that is timed to permit the expression of activity prior to a daytime meal. This hypothesis predicts that SCN activity should decrease prior to the onset of anticipatory activity and remain suppressed through the scheduled mealtime. To assess the hypothesis, neural activity in the SCN of mice anticipating a 4-5-h daily meal in the light period was measured using FOS immunohistochemistry and in vivo multiple unit electrophysiology. SCN FOS, quantified by optical density, was significantly reduced at the expected mealtime in food-anticipating mice with access to a running disk, compared to ad libitum-fed and acutely fasted controls. Group differences were not significant when FOS was quantified by other methods, or in mice without running disks. SCN electrical activity was markedly decreased during locomotion in some mice but increased in others. Changes in either direction were concurrent with locomotion, were not specific to food anticipation, and were not sustained during longer pauses. Reduced FOS indicates a net suppression of SCN activity that may depend on the intensity or duration of locomotion. The timing of changes in SCN activity relative to locomotion suggests that any effect of FEOs on SCN output is mediated indirectly, by feedback from neural or systemic correlates of locomotion. PMID:26701294

  3. Autoreceptor Control of Peptide/Neurotransmitter Corelease from PDF Neurons Determines Allocation of Circadian Activity in Drosophila

    Directory of Open Access Journals (Sweden)

    Charles Choi

    2012-08-01

    Full Text Available Drosophila melanogaster flies concentrate behavioral activity around dawn and dusk. This organization of daily activity is controlled by central circadian clock neurons, including the lateral-ventral pacemaker neurons (LNvs that secrete the neuropeptide PDF (pigment dispersing factor. Previous studies have demonstrated the requirement for PDF signaling to PDF receptor (PDFR-expressing dorsal clock neurons in organizing circadian activity. Although LNvs also express functional PDFR, the role of these autoreceptors has remained enigmatic. Here, we show that (1 PDFR activation in LNvs shifts the balance of circadian activity from evening to morning, similar to behavioral responses to summer-like environmental conditions, and (2 this shift is mediated by stimulation of the Gα,s-cAMP pathway and a consequent change in PDF/neurotransmitter corelease from the LNvs. These results suggest another mechanism for environmental control of the allocation of circadian activity and provide new general insight into the role of neuropeptide autoreceptors in behavioral control circuits.

  4. Effects of chronic administration and withdrawal of antidepressant agents on circadian activity rhythms in rats

    OpenAIRE

    Wollnik, Franziska

    1992-01-01

    Experimental and clinical studies indicate that clinical depression may be associated with disturbances of circadian rhythms. To explore the interaction between circadian rhythmicity, behavioral state, and monoaminergic systems, the present study investigated the effects of chronic administration and withdrawal of the following antidepressant agents on circadian wheel-running rhythms of laboratory rats: a) moclobemide, a reversible and selective monoamine oxidase (MAO) type A inhibitor; b) Ro...

  5. Quantification of colour Doppler activity in the wrist in patients with rheumatoid arthritis - the reliability of different methods for image selection and evaluation

    DEFF Research Database (Denmark)

    Ellegaard, K.; Torp-Pedersen, S.; Lund, H.;

    2008-01-01

    Purpose: The amount Of colour Doppler activity in the inflamed synovium is used to quantity inflammatory activity. The measurements may vary due to image selection, quantification method, and point in cardiac cycle. This study investigated the test-retest reliability Of ultrasound colour Doppler...... measurements in the wrist of patients with rheumatoid arthritis (RA) using different selection and quantification methods. Materials and Methods: 14 patients with RA had their wrist scanned twice by the same investigator with an interval of 30 Minutes, The images for analysis were selected either by the...... anatomical position only or by the anatomical position with maximum colour Doppler activity. Subsequently, the amount of colour Doppler was measured in an area defined by either the synovial tissue or by specific anatomical structures surrounding the synovial tissue. Results: The best test-retest reliability...

  6. Quantification of colour Doppler activity in the wrist in patients with rheumatoid arthritis--the reliability of different methods for image selection and evaluation

    DEFF Research Database (Denmark)

    Ellegaard, K; Torp-Pedersen, S; Lund, Hans;

    2008-01-01

    PURPOSE: The amount of colour Doppler activity in the inflamed synovium is used to quantify inflammatory activity. The measurements may vary due to image selection, quantification method, and point in cardiac cycle. This study investigated the test-retest reliability of ultrasound colour Doppler...... measurements in the wrist of patients with rheumatoid arthritis (RA) using different selection and quantification methods. MATERIALS AND METHODS: 14 patients with RA had their wrist scanned twice by the same investigator with an interval of 30 minutes. The images for analysis were selected either by the...... anatomical position only or by the anatomical position with maximum colour Doppler activity. Subsequently, the amount of colour Doppler was measured in an area defined by either the synovial tissue or by specific anatomical structures surrounding the synovial tissue. RESULTS: The best test-retest reliability...

  7. The CK2 kinase stabilizes CLOCK and represses its activity in the Drosophila circadian oscillator.

    Directory of Open Access Journals (Sweden)

    Aron Szabó

    Full Text Available Phosphorylation is a pivotal regulatory mechanism for protein stability and activity in circadian clocks regardless of their evolutionary origin. It determines the speed and strength of molecular oscillations by acting on transcriptional activators and their repressors, which form negative feedback loops. In Drosophila, the CK2 kinase phosphorylates and destabilizes the PERIOD (PER and TIMELESS (TIM proteins, which inhibit CLOCK (CLK transcriptional activity. Here we show that CK2 also targets the CLK activator directly. Downregulating the activity of the catalytic α subunit of CK2 induces CLK degradation, even in the absence of PER and TIM. Unexpectedly, the regulatory β subunit of the CK2 holoenzyme is not required for the regulation of CLK stability. In addition, downregulation of CK2α activity decreases CLK phosphorylation and increases per and tim transcription. These results indicate that CK2 inhibits CLK degradation while reducing its activity. Since the CK1 kinase promotes CLK degradation, we suggest that CLK stability and transcriptional activity result from counteracting effects of CK1 and CK2.

  8. Nogo-A-deficient transgenic rats show deficits in higher cognitive functions, decreased anxiety and altered circadian activity patterns

    Directory of Open Access Journals (Sweden)

    Tomas Petrasek

    2014-03-01

    Full Text Available Decreased levels of Nogo-A dependent signaling have been shown to affect behavior and cognitive functions. In Nogo-A knockout and knock-down laboratory rodents, behavioral alterations were observed, possibly corresponding with human neuropsychiatric diseases of neurodevelopmental origin, particularly schizophrenia. This study offers further insight into behavioral manifestations of Nogo-A knockdown in laboratory rats, focusing on spatial and non-spatial cognition, anxiety levels, circadian rhythmicity and activity patterns. Demonstrated is an impairment of cognitive functions and behavioral flexibility in a spatial active avoidance task, while non-spatial memory in a step-through avoidance task was spared. No signs of anhedonia, typical for schizophrenic patients, were observed in the animals. Some measures indicated lower anxiety levels in the Nogo-A deficient group. Circadian rhythmicity in locomotor activity was preserved in the Nogo-A-knockout rats and their circadian period (tau did not differ from controls. However, daily activity patterns were slightly altered in the knockdown animals. We conclude that a reduction of Nogo-A levels induces changes in CNS development, manifested as subtle alterations in cognitive functions, emotionality and activity patterns.

  9. Activity/inactivity circadian rhythm shows high similarities between young obesity-induced rats and old rats.

    Science.gov (United States)

    Bravo Santos, R; Delgado, J; Cubero, J; Franco, L; Ruiz-Moyano, S; Mesa, M; Rodríguez, A B; Uguz, C; Barriga, C

    2016-03-01

    The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly. PMID:27030628

  10. PPARα deficiency augments a ketogenic diet-induced circadian PAI-1 expression possibly through PPARγ activation in the liver

    International Nuclear Information System (INIS)

    Research highlights: → PPARα deficiency augments a ketogenic diet-induced circadian PAI-1 expression. → Hepatic expressions of PPARγ and PCG-1α are induced by a ketogenic diet. → PPARγ antagonist attenuates a ketogenic diet-induced PAI-1 expression. → Ketogenic diet advances the phase of circadian clock in a PPARα-independent manner. -- Abstract: An increased level of plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular diseases, and PAI-1 gene expression is under the control of molecular circadian clocks in mammals. We recently showed that PAI-1 expression is augmented in a phase-advanced circadian manner in mice fed with a ketogenic diet (KD). To determine whether peroxisome proliferator-activated receptor α (PPARα) is involved in hypofibrinolytic status induced by a KD, we examined the expression profiles of PAI-1 and circadian clock genes in PPARα-null KD mice. Chronic administration of bezafibrate induced the PAI-1 gene expression in a PPARα-dependent manner. Feeding with a KD augmented the circadian expression of PAI-1 mRNA in the hearts and livers of wild-type (WT) mice as previously described. The KD-induced mRNA expression of typical PPARα target genes such as Cyp4A10 and FGF21 was damped in PPARα-null mice. However, plasma PAI-1 concentrations were significantly more elevated in PPARα-null KD mice in accordance with hepatic mRNA levels. These observations suggest that PPARα activation is dispensable for KD-induced PAI-1 expression. We also found that hyperlipidemia, fatty liver, and the hepatic expressions of PPARγ and its coactivator PCG-1α were more effectively induced in PPARα-null, than in WT mice on a KD. Furthermore, KD-induced hepatic PAI-1 expression was significantly suppressed by supplementation with bisphenol A diglycidyl ether, a PPARγ antagonist, in both WT and PPARα-null mice. PPARγ activation seems to be involved in KD-induced hypofibrinolysis by augmenting PAI-1 gene expression

  11. A baculovirus photolyase with DNA repair activity and circadian clock regulatory function

    NARCIS (Netherlands)

    Biernat, M.A.; Eker, A.P.M.; Oers, van M.M.; Vlak, J.M.; Horst, van der G.T.J.; Chaves, I.

    2012-01-01

    Cryptochromes and photolyases belong to the same family of flavoproteins but, despite being structurally conserved, display distinct functions. Photolyases use visible light to repair ultraviolet-induced DNA damage. Cryptochromes, however, function as blue-light receptors, circadian photoreceptors,

  12. Predicting Energy Expenditure of Physical Activity Using Hip- and Wrist-Worn Accelerometers

    OpenAIRE

    Chen, Kong Y; Acra, Sari A.; Majchrzak, Karen; Donahue, Candice L.; Baker, Lemont; Clemens, Linda; Sun, Ming; Buchowski, Maciej S.

    2003-01-01

    To investigate the association between physical activity and health, we need accurate and detailed free-living physical activity measurements. The determination of energy expenditure of activity (EEACT) may also be useful in the treatment and maintenance of nutritional diseases such as diabetes mellitus. Minute-to-minute energy expenditure during a 24-h period was measured in 60 sedentary normal female volunteers (35.4 ± 9.0 years, body mass index 30.0 ± 5.9 kg/m2), using a state-of-the-art w...

  13. Chronic ethanol attenuates circadian photic phase resetting and alters nocturnal activity patterns in the hamster

    OpenAIRE

    Ruby, Christina L.; Brager, Allison J.; Marc A. DePaul; Prosser, Rebecca A.; Glass, J. David

    2009-01-01

    Acute ethanol (EtOH) administration impairs circadian clock phase resetting, suggesting a mode for the disruptive effect of alcohol abuse on human circadian rhythms. Here, we extend this research by characterizing the chronobiological effects of chronic alcohol consumption. First, daily profiles of EtOH were measured in the suprachiasmatic nucleus (SCN) and subcutaneously using microdialysis in hamsters drinking EtOH. In both cases, EtOH peaked near lights-off and declined throughout the dark...

  14. Adaptation to short photoperiods augments circadian food anticipatory activity in Siberian hamsters

    OpenAIRE

    Bradley, Sean P.; Prendergast, Brian J.

    2014-01-01

    Both the light-dark cycle and the timing of food intake can entrain circadian rhythms. Entrainment to food is mediated by a food entrainable circadian oscillator (FEO) that is formally and mechanistically separable from the hypothalamic light-entrainable oscillator. This experiment examined whether seasonal changes in day length affect the function of the FEO in male Siberian hamsters (Phodopus sungorus). Hamsters housed in long (LD; 15 h light/day) or short (SD; 9 h light/day) photoperiods w...

  15. Rats with minimal hepatic encephalopathy show reduced cGMP-dependent protein kinase activity in hypothalamus correlating with circadian rhythms alterations.

    Science.gov (United States)

    Felipo, Vicente; Piedrafita, Blanca; Barios, Juan A; Agustí, Ana; Ahabrach, Hanan; Romero-Vives, María; Barrio, Luis C; Rey, Beatriz; Gaztelu, Jose M; Llansola, Marta

    2015-01-01

    Patients with liver cirrhosis show disturbances in sleep and in its circadian rhythms which are an early sign of minimal hepatic encephalopathy (MHE). The mechanisms of these disturbances are poorly understood. Rats with porta-caval shunt (PCS), a model of MHE, show sleep disturbances reproducing those of cirrhotic patients. The aims of this work were to characterize the alterations in circadian rhythms in PCS rats and analyze the underlying mechanisms. To reach these aims, we analyzed in control and PCS rats: (a) daily rhythms of spontaneous and rewarding activity and of temperature, (b) timing of the onset of activity following turning-off the light, (c) synchronization to light after a phase advance and (d) the molecular mechanisms contributing to these alterations in circadian rhythms. PCS rats show altered circadian rhythms of spontaneous and rewarding activities (wheel running). PCS rats show more rest bouts during the active phase, more errors in the onset of motor activity and need less time to re-synchronize after a phase advance than control rats. Circadian rhythm of body temperature is also slightly altered in PCS rats. The internal period length (tau) of circadian rhythm of motor activity is longer in PCS rats. We analyzed some mechanisms by which hypothalamus modulate circadian rhythms. PCS rats show increased content of cGMP in hypothalamus while the activity of cGMP-dependent protein kinase was reduced by 41% compared to control rats. Altered cGMP-PKG pathway in hypothalamus would contribute to altered circadian rhythms and synchronization to light. PMID:26203935

  16. The Effects of the Mars Exploration Rovers (MER) Work Schedule Regime on Locomotor Activity Circadian Rhythms, Sleep and Fatigue

    Science.gov (United States)

    DeRoshia, Charles W.; Colletti, Laura C.; Mallis, Melissa M.

    2008-01-01

    This study assessed human adaptation to a Mars sol by evaluating sleep metrics obtained by actigraphy and subjective responses in 22 participants, and circadian rhythmicity in locomotor activity in 9 participants assigned to Mars Exploration Rover (MER) operational work schedules (24.65 hour days) at the Jet Propulsion Laboratory in 2004. During MER operations, increased work shift durations and reduced sleep durations and time in bed were associated with the appearance of pronounced 12-hr (circasemidian) rhythms with reduced activity levels. Sleep duration, workload, and circadian rhythm stability have important implications for adaptability and maintenance of operational performance not only of MER operations personnel but also in space crews exposed to a Mars sol of 24.65 hours during future Mars missions.

  17. Scapholunate kinematics of asymptomatic wrists in comparison with symptomatic contralateral wrists using four-dimensional CT examinations: initial clinical experience

    International Nuclear Information System (INIS)

    Using four-dimensional CT scan (4DCT), we aimed at showing the kinematics of scapholunate (SL) interval in asymptomatic wrists in comparison with symptomatic contralateral wrists with inconclusive radiographic findings. This is an IRB approved, HIPPA compliant, retrospective study. Patients suspected of SL interosseous ligament (SLIL) injuries were referred for further evaluation of chronic wrist pain (>3 months). Twelve wrists (11 subjects) with chronic symptoms and inconclusive plain radiographs and 10 asymptomatic wrists (in 10 different subjects) were scanned using 4DCT. The minimum SL interval was measured during three wrist motions: relaxed-to-clenched fist, flexion-to-extension, and radial-to-ulnar-deviation. Changes were recorded using double-oblique multiplanar reformation technique. We extracted the normal limits of the SL interval as measured by dynamic CT scanning during active motion in asymptomatic wrists. In asymptomatic wrists, the average SL interval was observed to be smaller than 1 mm during all motions. In symptomatic wrists, during exams performed with clenched fist (SL interval (mean ± SD) = 2.53 ± 1.19 mm), extension (2.54 ± 1.48 mm) or ulnar deviation (2.06 ± 1.12 mm), the average SL interval was more than 2 mm. In contrast to symptomatic wrists, no significant change in SL interval measurements was detected during wrist motions in asymptomatic wrists. There was a mild to moderate correlation between SL interval change and presence/absence of symptoms (point-biserial correlation coefficients: 0.29-0.55). In patients with wrist pain suspicious for SLIL injury and inconclusive radiographs, SL interval increase can be detected with 4DCT in the symptomatic wrist compared to the asymptomatic wrist. (orig.)

  18. Scapholunate kinematics of asymptomatic wrists in comparison with symptomatic contralateral wrists using four-dimensional CT examinations: initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Demehri, Shadpour; Hafezi-Nejad, Nima; Morelli, John N.; Thakur, Uma; Eng, John [Johns Hopkins University, Musculoskeletal Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Lifchez, Scott D.; Shores, Jaimie T. [Johns Hopkins University, Department of Plastic and Reconstructive Surgery, Baltimore, MD (United States); Means, Kenneth R. [MedStar Union Memorial Hospital, The Curtis National Hand Center, Baltimore, MD (United States)

    2016-04-15

    Using four-dimensional CT scan (4DCT), we aimed at showing the kinematics of scapholunate (SL) interval in asymptomatic wrists in comparison with symptomatic contralateral wrists with inconclusive radiographic findings. This is an IRB approved, HIPPA compliant, retrospective study. Patients suspected of SL interosseous ligament (SLIL) injuries were referred for further evaluation of chronic wrist pain (>3 months). Twelve wrists (11 subjects) with chronic symptoms and inconclusive plain radiographs and 10 asymptomatic wrists (in 10 different subjects) were scanned using 4DCT. The minimum SL interval was measured during three wrist motions: relaxed-to-clenched fist, flexion-to-extension, and radial-to-ulnar-deviation. Changes were recorded using double-oblique multiplanar reformation technique. We extracted the normal limits of the SL interval as measured by dynamic CT scanning during active motion in asymptomatic wrists. In asymptomatic wrists, the average SL interval was observed to be smaller than 1 mm during all motions. In symptomatic wrists, during exams performed with clenched fist (SL interval (mean ± SD) = 2.53 ± 1.19 mm), extension (2.54 ± 1.48 mm) or ulnar deviation (2.06 ± 1.12 mm), the average SL interval was more than 2 mm. In contrast to symptomatic wrists, no significant change in SL interval measurements was detected during wrist motions in asymptomatic wrists. There was a mild to moderate correlation between SL interval change and presence/absence of symptoms (point-biserial correlation coefficients: 0.29-0.55). In patients with wrist pain suspicious for SLIL injury and inconclusive radiographs, SL interval increase can be detected with 4DCT in the symptomatic wrist compared to the asymptomatic wrist. (orig.)

  19. Selective pharmacological blockade of the 5-HT7 receptor attenuates light and 8-OH-DPAT induced phase shifts of mouse circadian wheel running activity

    Directory of Open Access Journals (Sweden)

    Jonathan eShelton

    2015-01-01

    Full Text Available Recent reports have illustrated a reciprocal relationship between circadian rhythm disruption and mood disorders. The 5-HT7 receptor may provide a crucial link between the two sides of this equation since the receptor plays a critical role in sleep, depression, and circadian rhythm regulation. To further define the role of the 5-HT7 receptor as a potential pharmacotherapy to correct circadian rhythm disruptions, the current study utilized the selective 5-HT7 antagonist JNJ-18038683 (10 mg/kg in three different circadian paradigms. While JNJ-18038683 was ineffective at phase shifting the onset of wheel running activity in mice when administered at different circadian time (CT points across the circadian cycle, pretreatment with JNJ-18038683 blocked non-photic phase advance (CT6 induced by the 5-HT1A/7 receptor agonist 8-OH-DPAT (3 mg/kg. Since light induced phase shifts in mammals are partially mediated via the modulation of the serotonergic system, we determined if JNJ-18038683 altered phase shifts induced by a light pulse at times known to phase delay (CT15 or advance (CT22 wheel running activity in free running mice. Light exposure resulted in a robust shift in the onset of activity in vehicle treated animals at both times tested. Administration of JNJ-18038683 significantly attenuated the light-induced phase delay and completely blocked the phase advance. The current study demonstrates that pharmacological blockade of the 5-HT7 receptor by JNJ-18038683 blunts both non-photic and photic phase shifts of circadian wheel running activity in mice. These findings highlight the importance of the 5-HT7 receptor in modulating circadian rhythms. Due to the opposite modulating effects of light resetting between diurnal and nocturnal species, pharmacotherapy targeting the 5-HT7 receptor in conjunction with bright light therapy may prove therapeutically beneficial by correcting the desynchronization of internal rhythms observed in depressed individuals.

  20. Circadian Rest/Activity Rhythms in Knee Osteoarthritis with Insomnia: A Study of Osteoarthritis Patients and Pain-Free Controls with Insomnia or Normal Sleep

    OpenAIRE

    Spira, Adam P.; Runko, Virginia T.; Finan, Patrick H.; Kaufmann, Christopher N.; Bounds, Sara C; Liu, Lianqi; Buenaver, Luis F.; McCauley, Lea M.; Ancoli-Israel, Sonia; Smith, Michael T

    2014-01-01

    Aberrant circadian rest/activity rhythms (RARs) may promote poor aging-related health outcomes. Osteoarthritis and chronic insomnia are common age-related conditions, but the circadian RARs of each group have not been well characterized or compared. We evaluated actigraphic RARs in individuals with: (1) knee osteoarthritis (KOA) only; (2) chronic insomnia only; (3) KOA + insomnia; and (4) pain-free good sleepers. Compared to participants with KOA only, those with KOA + insomnia had less robus...

  1. The circadian clock regulates rhythmic activation of the NRF2/glutathione-mediated antioxidant defense pathway to modulate pulmonary fibrosis

    Science.gov (United States)

    Pekovic-Vaughan, Vanja; Gibbs, Julie; Yoshitane, Hikari; Yang, Nan; Pathiranage, Dharshika; Guo, Baoqiang; Sagami, Aya; Taguchi, Keiko; Bechtold, David; Loudon, Andrew; Yamamoto, Masayuki; Chan, Jefferson; van der Horst, Gijsbertus T.J.; Fukada, Yoshitaka; Meng, Qing-Jun

    2014-01-01

    The disruption of the NRF2 (nuclear factor erythroid-derived 2-like 2)/glutathione-mediated antioxidant defense pathway is a critical step in the pathogenesis of several chronic pulmonary diseases and cancer. While the mechanism of NRF2 activation upon oxidative stress has been widely investigated, little is known about the endogenous signals that regulate the NRF2 pathway in lung physiology and pathology. Here we show that an E-box-mediated circadian rhythm of NRF2 protein is essential in regulating the rhythmic expression of antioxidant genes involved in glutathione redox homeostasis in the mouse lung. Using an in vivo bleomycin-induced lung fibrosis model, we reveal a clock “gated” pulmonary response to oxidative injury, with a more severe fibrotic effect when bleomycin was applied at a circadian nadir in NRF2 levels. Timed administration of sulforaphane, an NRF2 activator, significantly blocked this phenotype. Moreover, in the lungs of the arrhythmic ClockΔ19 mice, the levels of NRF2 and the reduced glutathione are constitutively low, associated with increased protein oxidative damage and a spontaneous fibrotic-like pulmonary phenotype. Our findings reveal a pivotal role for the circadian control of the NRF2/glutathione pathway in combating oxidative/fibrotic lung damage, which might prompt new chronotherapeutic strategies for the treatment of human lung diseases, including idiopathic pulmonary fibrosis. PMID:24637114

  2. Advances in wrist arthroscopy.

    Science.gov (United States)

    Wolf, Jennifer Moriatis; Dukas, Alex; Pensak, Michael

    2012-11-01

    Since its introduction more than three decades ago, wrist arthroscopy has continually evolved. The procedure has a wide list of indications, including diagnostic and management applications. The scope of practice for the wrist arthroscopic surgeon includes management of triangulofibrocartilage complex pathology, evaluation and management of carpal instability, assistance in fracture reduction of the radius and scaphoid, treatment of trapeziometacarpal synovitis and arthritis, distal ulnar and carpal bone excisions, and salvage procedures. In addition, innovations such as new portals and smaller arthroscopes have expanded the applications of wrist arthroscopy. PMID:23118138

  3. Associations of work activities requiring pinch or hand grip or exposure to hand-arm vibration with finger and wrist osteoarthritis

    DEFF Research Database (Denmark)

    Hammer, Paula E C; Shiri, Rahman; Kryger, Ann I;

    2014-01-01

    the associations of radiographic diagnosed finger and/or wrist joint OA with work activities involving pinch or hand grip or exposure to HAV. We used specific criteria to evaluate completeness of reporting, potential confounding, and bias. Pooled odds ratios (OR) were computed using random......-effects meta-analyses. RESULTS: Of the 19 studies included, 17 were cross-sectional, 1 was a prospective cohort, and 1 a case-control study. The meta-analyses of studies that controlled their estimates for at least age and gender showed the associations of pinch grip work with proximal interphalangeal joint...

  4. The association of quality of life with potentially remediable disruptions of circadian sleep/activity rhythms in patients with advanced lung cancer

    Directory of Open Access Journals (Sweden)

    Braun Donald P

    2011-05-01

    Full Text Available Abstract Background Cancer patients routinely develop symptoms consistent with profound circadian disruption, which causes circadian disruption diminished quality of life. This study was initiated to determine the relationship between the severity of potentially remediable cancer-associated circadian disruption and quality of life among patients with advanced lung cancer. Methods We concurrently investigated the relationship between the circadian rhythms of 84 advanced lung cancer patients and their quality of life outcomes as measured by the EORTC QLQ C30 and Ferrans and Powers QLI. The robustness and stability of activity/sleep circadian daily rhythms were measured by actigraphy. Fifty three of the patients in the study were starting their definitive therapy following diagnosis and thirty one patients were beginning second-line therapy. Among the patients who failed prior therapy, the median time between completing definitive therapy and baseline actigraphy was 4.3 months, (interquartile range 2.1 to 9.8 months. Results We found that circadian disruption is universal and severe among these patients compared to non-cancer-bearing individuals. We found that each of these patient's EORTC QLQ C30 domain scores revealed a compromised capacity to perform the routine activities of daily life. The severity of several, but not all, EORTC QLQ C30 symptom items correlate strongly with the degree of individual circadian disruption. In addition, the scores of all four Ferrans/Powers QLI domains correlate strongly with the degree of circadian disruption. Although Ferrans/Powers QLI domain scores show that cancer and its treatment spared these patients' emotional and psychological health, the QLI Health/Function domain score revealed high levels of patients' dissatisfaction with their health which is much worse when circadian disruption is severe. Circadian disruption selectively affects specific Quality of Life domains, such as the Ferrans/Powers Health

  5. Dexterous Humanoid Robotic Wrist

    Science.gov (United States)

    Ihrke, Chris A. (Inventor); Bridgwater, Lyndon (Inventor); Reich, David M. (Inventor); Wampler, II, Charles W. (Inventor); Askew, Scott R. (Inventor); Diftler, Myron A. (Inventor); Nguyen, Vienny (Inventor)

    2013-01-01

    A humanoid robot includes a torso, a pair of arms, a neck, a head, a wrist joint assembly, and a control system. The arms and the neck movably extend from the torso. Each of the arms includes a lower arm and a hand that is rotatable relative to the lower arm. The wrist joint assembly is operatively defined between the lower arm and the hand. The wrist joint assembly includes a yaw axis and a pitch axis. The pitch axis is disposed in a spaced relationship to the yaw axis such that the axes are generally perpendicular. The pitch axis extends between the yaw axis and the lower arm. The hand is rotatable relative to the lower arm about each of the yaw axis and the pitch axis. The control system is configured for determining a yaw angle and a pitch angle of the wrist joint assembly.

  6. MRI of the wrist

    Energy Technology Data Exchange (ETDEWEB)

    Dick, Elizabeth A. [Department of MRI, St Mary' s Hospital, Praed St, London W2 1NY (United Kingdom)], E-mail: dickelizabeth@hotmail.com; Burnett, Carole; Gedroyc, Wladyslaw M.W. [Department of MRI, St Mary' s Hospital, Praed St, London W2 1NY (United Kingdom)

    2008-08-15

    Magnetic resonance imaging of the wrist is increasingly recognised as the imaging modality of choice in wrist disorders as image resolution improves and clinicians realise its potential. Consequently the ability to confidently interpret such imaging will become more important to both general and musculoskeletal radiologists. This article reviews current optimal imaging protocols and describes common abnormalities with a particular emphasis on less well understood topics such as intercalated segment instability, the triangular fibrocartilage complex and carpal tunnel syndrome.

  7. Linear and nonlinear analyses of multi-channel mechanomyographic recordings reveal heterogeneous activation of wrist extensors in presence of delayed onset muscle soreness.

    Science.gov (United States)

    Madeleine, Pascal; Hansen, Ernst A; Samani, Afshin

    2014-12-01

    In this study, we applied multi-channel mechanomyographic (MMG) recordings in combination with linear and nonlinear analyses to investigate muscular and musculotendinous effects of high intensity eccentric exercise. Twelve accelerometers arranged in a 3 × 4 matrix over the dominant elbow muscles were used to detect MMG activity in 12 healthy participants. Delayed onset muscle soreness was induced by repetitive high intensity eccentric contractions of the wrist extensor muscles. Average rectified values (ARV) as well as percentage of recurrence (%REC) and percentage of determinism (%DET) extracted from recurrence quantification analysis were computed from data obtained during static-dynamic contractions performed before exercise, immediately after exercise, and in presence of muscle soreness. A linear mixed model was used for the statistical analysis. The ARV, %REC, and %DET maps revealed heterogeneous MMG activity over the wrist extensor muscles before, immediately after, and in presence of muscle soreness (Panalysis can be suggested as a tool for detection of MMG changes in presence of muscle soreness. PMID:25277830

  8. Treatment of behavioural, cognitive and circadian rest-activity cycle disturbances in Alzheimer's disease: haloperidol vs. quetiapine

    OpenAIRE

    Savaskan, E; Schnitzler, C; Schröder, C.; Cajochen, C; Müller-Spahn, F; Wirz-Justice, A.

    2006-01-01

    This 5-wk, open-label, comparative study investigated the effects of quetiapine and haloperidol on behavioural, cognitive and circadian rest-activity cycle disturbances in patients with Alzheimer's disease (AD). Out of a total of 30 patients enrolled in the study, there were 22 completers, 11 in the quetiapine group (mean age 81.9+/-1.8 yr, mean baseline MMSE 19.9+/-1.3, mean dose 125 mg) and 11 in the haloperidol group (mean age 82.3+/-2.5 yr, mean baseline MMSE 18.1+/-1.3, mean dose 1.9 mg)...

  9. Monitoring anti-TNF{alpha} treatment in RA: Responsiveness of magnetic resonance imaging and ultrasonography of the dominant wrist compared to conventional measures of disease activity and structural damage

    DEFF Research Database (Denmark)

    Haavardsholm, Espen A; Ostergaard, Mikkel; Hammer, Hilde Berner;

    2008-01-01

    RA patients (N=36, median age 53 years, disease duration 7.6 years and DAS28 5.7) was evaluated by core measures of disease activity, US (one wrist), MRI (one wrist) and conventional radiography (CR, both hands and wrists) at initiation of treatment with anti-TNFalpha agents and after 3, 6 and 12......OBJECTIVES: The objective of this study was to evaluate the responsiveness of magnetic resonance imaging (MRI) and ultrasonography (US) compared to conventional measures of disease activity and structural damage in RA patients during the first year of anti-TNFalpha treatment. METHODS: A cohort of...... months. Responsiveness was assessed by standardized response means (SRM). Accepted thresholds were applied to classify responsiveness as trivial, low, moderate or good. RESULTS: MRI synovitis (SRM between -0.79 and -0.92) and the MRI total inflammation score comprising synovitis, tenosynovitis and bone...

  10. Long term effects of prenatal exposure to low level gamma rays on spontaneous circadian motor activity of male mice

    International Nuclear Information System (INIS)

    The spontaneous circadian motor activity of first generation (F1) hybrid male C57BL/6 x C3H mice irradiated with gamma rays on the 14th day of gestation was studied at the following ages : young (6-7 months), adult (12-13 months), and old (19-20 months). Doses were 0.1, 0.2, 0.5 or 1.0 Gy. A 12-hour day-night cycle was maintained with light on at 6:00 hr. Spontaneous circadian motor activity was recorded with a capacitance-induction motility monitor for 48 consecutive hours. Activity was measured at 2-hour intervals, and the data stored on computer discs. The activity of the 1.0 Gy group recorded at 22:00 and 2:00 hr for young mice and at 2:00 hr for adult ones was significantly higher than that of the age-matched control group. Results suggest that male mice irradiated with 1.0 Gy at gestational day 14 show nocturnal hyperactivity in the young and adult stages. (author)

  11. Magnetic resonance imaging-determined synovial membrane volume as a marker of disease activity and a predictor of progressive joint destruction in the wrists of patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Hansen, M; Stoltenberg, M;

    1999-01-01

    -modifying antirheumatic drug (DMARD) therapy alone (11 patients) or DMARDs in combination with oral prednisolone (15 patients), were followed up for 1 year with contrast-enhanced MRI of the dominant wrist (months 0, 3, 6, and 12), conventional radiography (months 0 and 12), and clinical and biochemical examinations. Bone......, or with prednisolone treatment. In none of 5 wrists with baseline volumes <5 cm3, but in 8 of 10 wrists with baseline volumes > or =10 cm3, erosive progression was found by MRI and/or radiography, indicating a predictive value of synovial membrane volumes. MRI was more sensitive than radiography for......OBJECTIVE: To evaluate the synovial membrane volume, determined by magnetic resonance imaging (MRI), as a marker of joint disease activity and a predictor of progressive joint destruction in rheumatoid arthritis (RA). METHODS: Twenty-six patients with RA, randomized to receive disease...

  12. Destructive wrist arthropathy of pseudogout

    Energy Technology Data Exchange (ETDEWEB)

    Smathers, R.L.; Keats, T.E.; Stelling, C.B.

    1982-01-01

    The wrist is a frequent site of arthropathy in the pseudogout syndrome (calcium pyrophosphate dihydrate crystal deposition disease). Three cases of severe wrist arthropathy are presented to emphasize the destructive changes which may occur, including necrosis or collapse of the lunate and navicular bones. The roentgenographic findings characteristic of pseudogout in the wrist are discussed.

  13. X-Ray Exam: Wrist

    Science.gov (United States)

    ... Tropical Delight: Melon Smoothie Pregnant? Your Baby's Growth X-Ray Exam: Wrist KidsHealth > For Parents > X-Ray Exam: Wrist Print A A A Text Size ... español Radiografía: muñeca What It Is A wrist X-ray is a safe and painless test that uses ...

  14. Circadian clocks, epigenetics, and cancer

    KAUST Repository

    Masri, Selma

    2015-01-01

    The interplay between circadian rhythm and cancer has been suggested for more than a decade based on the observations that shift work and cancer incidence are linked. Accumulating evidence implicates the circadian clock in cancer survival and proliferation pathways. At the molecular level, multiple control mechanisms have been proposed to link circadian transcription and cell-cycle control to tumorigenesis.The circadian gating of the cell cycle and subsequent control of cell proliferation is an area of active investigation. Moreover, the circadian clock is a transcriptional system that is intricately regulated at the epigenetic level. Interestingly, the epigenetic landscape at the level of histone modifications, DNA methylation, and small regulatory RNAs are differentially controlled in cancer cells. This concept raises the possibility that epigenetic control is a common thread linking the clock with cancer, though little scientific evidence is known to date.This review focuses on the link between circadian clock and cancer, and speculates on the possible connections at the epigenetic level that could further link the circadian clock to tumor initiation or progression.

  15. Circadian rhythms of body temperature and locomotor activity in aging BALB/c mice: early and late life span predictors.

    Science.gov (United States)

    Basso, Andrea; Del Bello, Giovanna; Piacenza, Francesco; Giacconi, Robertina; Costarelli, Laura; Malavolta, Marco

    2016-08-01

    Impairment of one or more parameters of circadian rhythms (CR) of body temperature (BT) and locomotor activity (LMA) are considered among the hallmarks of mammalian aging. These alterations are frequently used as markers for imminent death in laboratory mice. However, there are still contradictory data for particular strains and it is also uncertain which changes might predict senescence changes later in life, including the force of mortality. In the present paper we use telemetry to study LMA and CR of BT during aging of BALB/c mice. At our knowledge this is the first time that CR of BT and LMA are investigated in this strain in a range of age covering the whole lifespan, from young adult up to very old age. CR of BT was analyzed with a cosine model using a cross sectional approach and follow-up measurements. The results show that BT, LMA, amplitude, goodness-of-fit (GoF) to circadian cycle of temperature decrease with different shapes during chronological age. Moreover, we found that the % change of amplitude and BT in early life (5-19 months) can predict the remaining lifespan of the mice. Later in life (22-32 months), best predictors are single measurements of LMA and GoF. The results of this study also offer potential measures to rapidly identifying freely unrestrained mice with the worst longitudinal outcome and against which existing or novel biomarkers and treatments may be assessed. PMID:26820297

  16. Effect of a strong, DC-induced magnetic field on circadian singing activity of the house cricket (orthoptera:gryllidae)

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, K.C.; Bitzer, R.J.; Galliart, L. [Iowa State Univ., Ames, IA (United States)] [and others

    1995-05-01

    We investigated the effect of a strong, DC-induced electromagnetic field (EMF) on the circadian singing activity of the house cricket, Acheta domesticus (L.). Groups of 10 crickets were exposed to strong, DC-induced EMFs under two light regimes, 12:12 (L:D) h and 0:24 (L:D) h. Exposure to the strong EMF resulted in an increase in mean time per hour during which one or more crickets were singing and in number of crickets singing per hour. Correcting for phase shift during O:24 (L:D) h, the daily pattern of singing was apparently unaffected by any treatment. The greatest percentage of singing and number of crickets singing per hour occurred during actual or expected scotophase. This is the first report of an increase in insect activity during exposure to a strong DC-induced EMF.

  17. Monitoring circadian rhythms of individual honey bees in a social environment reveals social influences on postembryonic ontogeny of activity rhythms.

    Science.gov (United States)

    Meshi, A; Bloch, G

    2007-08-01

    Social factors constitute an important component of the environment of many animals and have a profound influence on their physiology and behavior. Studies of social influences on circadian rhythms have been hampered by a methodological trade-off: automatic data acquisition systems obtain high-quality data but are effective only for individually isolated animals and therefore compromise by requiring a context that may not be sociobiologically relevant. Human observers can monitor animal activity in complex social environments but are limited in the resolution and quality of data that can be gathered. The authors developed and validated a method for prolonged, automatic, high-quality monitoring of focal honey bees in a relatively complex social environment and with minimal illumination. The method can be adapted for studies on other animals. The authors show that the system provides a reliable estimation of the actual path of a focal bee, only rarely misses its location for > 1 min, and removes most nonspecific signals from the background. Using this system, the authors provide the first evidence of social influence on the ontogeny of activity rhythms. Young bees that were housed with old foragers show ~24-h rhythms in locomotor activity at a younger age and with stronger rhythms than bees housed with a similar number of young bees. By contrast, the maturation of the hypopharyngeal glands was slower in bees housed with foragers, similar to findings in previous studies. The morphology and function of the hypopharyngeal glands vary along with age-based division of labor. Therefore, these findings indicate that social inhibition of task-related maturation was effective in the experimental setup. This study suggests that although the ontogeny of circadian rhythms is typically correlated with the age-based division of labor, their social regulation is different. PMID:17660451

  18. Animation of Phoenix's Wrist Unlatching

    Science.gov (United States)

    2008-01-01

    This animation shows what happened underneath Phoenix's Robotic Arm wrist on Sol 3. The pin that goes through the loop is what holds the wrist in place. The rotation of the wrist pops the pin free. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  19. Sleep and circadian rhythms

    Science.gov (United States)

    Monk, Timothy H.

    1991-01-01

    Three interacting processes are involved in the preservation of circadian rhythms: (1) endogenous rhythm generation mechanisms, (2) entrainment mechanisms to keep these rhythms 'on track', and (3) exogenous masking processes stemming from changes in environment and bahavior. These processes, particularly the latter two, can be dramatically affected in individuals of advanced age and in space travelers, with a consequent disruption in sleep and daytime functioning. This paper presents results of a phase-shift experiment investigating the age-related effects of the exogeneous component of circadian rhythms in various physiological and psychological functions by comparing these functions in middle aged and old subjects. Dramatic differences were found between the two age groups in measures of sleep, mood, activation, and performance efficiency.

  20. Postoperative circadian disturbances

    DEFF Research Database (Denmark)

    Gögenur, Ismail

    2010-01-01

    postoperative recovery parameters, and if pharmacological administration of chronobiotics could improve postoperative recovery. Circadian rhythm disturbances were found in all the examined endogenous rhythms. A delay was found in the endogenous rhythm of plasma melatonin and excretion of the metabolite of...... after major surgery was increased on the fourth day after surgery and the total excretion of AMT6s in urine was correlated to sleep efficiency and wake time after sleep onset, but was not correlated to the occurrence of postoperative cognitive dysfunction. We could only prove an effect of melatonin...... rhythm, autonomic nervous system tone, myocardial ischaemia and activity rhythm after surgery. Correlation exists between circadian rhythm parameters and measures of postoperative sleep quality and recovery. However, oral melatonin treatment in the first three nights after surgery, cannot yet be...

  1. PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression possibly through PPAR{gamma} activation in the liver

    Energy Technology Data Exchange (ETDEWEB)

    Oishi, Katsutaka, E-mail: k-ooishi@aist.go.jp [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Uchida, Daisuke [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki (Japan); Ohkura, Naoki [Department of Clinical Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamihara, Kanagawa (Japan); Horie, Shuichi [Department of Clinical Biochemistry, Kagawa Nutrition University, Sakado, Saitama (Japan)

    2010-10-15

    Research highlights: {yields} PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression. {yields} Hepatic expressions of PPAR{gamma} and PCG-1{alpha} are induced by a ketogenic diet. {yields} PPAR{gamma} antagonist attenuates a ketogenic diet-induced PAI-1 expression. {yields} Ketogenic diet advances the phase of circadian clock in a PPAR{alpha}-independent manner. -- Abstract: An increased level of plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular diseases, and PAI-1 gene expression is under the control of molecular circadian clocks in mammals. We recently showed that PAI-1 expression is augmented in a phase-advanced circadian manner in mice fed with a ketogenic diet (KD). To determine whether peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) is involved in hypofibrinolytic status induced by a KD, we examined the expression profiles of PAI-1 and circadian clock genes in PPAR{alpha}-null KD mice. Chronic administration of bezafibrate induced the PAI-1 gene expression in a PPAR{alpha}-dependent manner. Feeding with a KD augmented the circadian expression of PAI-1 mRNA in the hearts and livers of wild-type (WT) mice as previously described. The KD-induced mRNA expression of typical PPAR{alpha} target genes such as Cyp4A10 and FGF21 was damped in PPAR{alpha}-null mice. However, plasma PAI-1 concentrations were significantly more elevated in PPAR{alpha}-null KD mice in accordance with hepatic mRNA levels. These observations suggest that PPAR{alpha} activation is dispensable for KD-induced PAI-1 expression. We also found that hyperlipidemia, fatty liver, and the hepatic expressions of PPAR{gamma} and its coactivator PCG-1{alpha} were more effectively induced in PPAR{alpha}-null, than in WT mice on a KD. Furthermore, KD-induced hepatic PAI-1 expression was significantly suppressed by supplementation with bisphenol A diglycidyl ether, a PPAR{gamma} antagonist, in both WT and PPAR

  2. Epidemiology of acute wrist trauma

    DEFF Research Database (Denmark)

    Larsen, C F; Lauritsen, Jens

    1993-01-01

    Epidemiological data on wrist injuries in a population can be used for planning by applying them to criteria for care and thus deriving estimates of provisions for care according to currently desirable standards. In a 1-year study all patients > or = 15 years with acute wrist trauma and treated...... in the emergency room were examined according to an algorithm until a diagnosis was established. The overall incidence of wrist trauma was 69 per 10,000 inhabitants per year. Incidence of wrist trauma requiring x-ray examination was 58 per 10,000 per year. The incidence of distal radius fractures was 27 per 10...... using data from a population-based study. A completeness rate of 0.56 (95% confidence interval: 0.31-0.78) was found. An x-ray had been taken for all patients reporting a fracture thus justifying the use of fractures as an incidence measure when comparing groups of patients with wrist trauma....

  3. dTRPA1 in Non-circadian Neurons Modulates Temperature-dependent Rhythmic Activity in Drosophila melanogaster.

    Science.gov (United States)

    Das, Antara; Holmes, Todd C; Sheeba, Vasu

    2016-06-01

    In fruit flies Drosophila melanogaster, environmental cycles of light and temperature are known to influence behavioral rhythms through dedicated sensory receptors. But the thermosensory pathways and molecular receptors by which thermal cycles modulate locomotor activity rhythms remain unclear. Here, we report that neurons expressing warmth-activated ion channel Drosophila Transient Receptor Potential-A1 (dTRPA1) modulate distinct aspects of the rhythmic activity/rest rhythm in a light-dependent manner. Under light/dark (LD) cycles paired with constantly warm ambient conditions, flies deficient in dTRPA1 expression are unable to phase morning and evening activity bouts appropriately. Correspondingly, we show that electrical activity of a few neurons targeted by the dTRPA1(SH)-GAL4 driver modulates temperature-dependent phasing of activity/rest rhythm under LD cycles. The expression of dTRPA1 also affects behavior responses to temperature cycles combined with constant dark (DD) or light (LL) conditions. We demonstrate that the mid-day "siesta" exhibited by flies under temperature cycles in DD is dependent on dTRPA1 expression in a small number of neurons that include thermosensory anterior cell neurons. Although a small subset of circadian pacemaker neurons may express dTRPA1, we show that CRY-negative dTRPA1(SH)-GAL4 driven neurons are critical for the suppression of mid-thermophase activity, thus enabling flies to exhibit siesta. In contrast to temperature cycles in DD, under LL, dTRPA1 is not required for exhibiting siesta but is important for phasing of evening peak. Our studies show that activity/rest rhythms are modulated in a temperature-dependent manner via signals from dTRPA1(SH)-GAL4 driven neurons. Taken together, these results emphasize the differential influence of thermoreceptors on rhythmic behavior in fruit flies in coordination with light inputs. PMID:26868037

  4. The instability of wrist joint and total wrist replacement.

    Science.gov (United States)

    Ma, Jin-Xing; Xu, Yong-Qing

    2016-02-01

    Total wrist arthroplasty are not used as widely as total knee and hip replacement. The functional hands are requiring surgeons to design a durable and functional satisfying prosthesis. This article will list the main reasons that cause the failure of the prosthesis. Some remarkable and representative prostheses are listed to show the devolvement of total wrist prosthesis and their individual special innovations to fix the problems. And the second part we will discuss the part that biomechanical elements act in the total wrist replacement (TWA). Summarize and find out what the real problem is and how we can find a way to fix it. PMID:27033274

  5. Circadian Rhythm Abnormalities

    OpenAIRE

    Zee, Phyllis C.; Attarian, Hrayr; Videnovic, Aleksandar

    2013-01-01

    Purpose: This article reviews the recent advances in understanding of the fundamental properties of circadian rhythms and discusses the clinical features, diagnosis, and treatment of circadian rhythm sleep disorders (CRSDs).

  6. Circadian Rhythm Sleep Disorders

    Science.gov (United States)

    ... psychiatric and other sleep disorders such as sleep apnea and individuals with a strong need for stable ... and circadian rhythm sleep disorder, free-running type. Prevalence • The prevalence of circadian rhythm sleep disorders in ...

  7. Midcarpal Hemiarthroplasty for Wrist Arthritis: Rationale and Early Results

    OpenAIRE

    Vance, Michael C.; Packer, Greg; Tan, David; Crisco, J.J. Trey; Wolfe, Scott W.

    2012-01-01

    Midcarpal hemiarthroplasty is a novel motion-preserving treatment for radiocarpal arthritis and is an alternative to current procedures that provide pain relief at the expense of wrist biomechanics and natural motion. It is indicated primarily in active patients with a well-preserved distal row and debilitating arthritic symptoms. By resurfacing the proximal carpal row, midcarpal arthroplasty relieves pain while preserving the midcarpal articulation and the anatomic center of wrist rotation. ...

  8. The circadian clock coordinates ribosome biogenesis.

    Directory of Open Access Journals (Sweden)

    Céline Jouffe

    Full Text Available Biological rhythms play a fundamental role in the physiology and behavior of most living organisms. Rhythmic circadian expression of clock-controlled genes is orchestrated by a molecular clock that relies on interconnected negative feedback loops of transcription regulators. Here we show that the circadian clock exerts its function also through the regulation of mRNA translation. Namely, the circadian clock influences the temporal translation of a subset of mRNAs involved in ribosome biogenesis by controlling the transcription of translation initiation factors as well as the clock-dependent rhythmic activation of signaling pathways involved in their regulation. Moreover, the circadian oscillator directly regulates the transcription of ribosomal protein mRNAs and ribosomal RNAs. Thus the circadian clock exerts a major role in coordinating transcription and translation steps underlying ribosome biogenesis.

  9. 21 CFR 888.3810 - Wrist joint ulnar (hemi-wrist) polymer prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint ulnar (hemi-wrist) polymer prosthesis. 888.3810 Section 888.3810 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-wrist) polymer prosthesis. (a) Identification. A wrist joint ulnar (hemi-wrist) polymer...

  10. Quantitative EEG Monitoring of Vigilance: Effects of Sleep Deprivation, Circadian Phase and Sympathetic Activation

    Science.gov (United States)

    Dijk, Derk-Jan

    1999-01-01

    Shuttle astronauts typically sleep only 6 to 6.5 hours per day while in orbit. This sleep loss is related to recurrent sleep cycle shifting--due to mission-dependent orbital mechanics and mission duration requirements-- and associated circadian displacement of sleep, the operational demands of space flight, noise and space motion sickness. Such sleep schedules are known to produce poor subjective sleep quality, daytime sleepiness, reduced attention, negative mood, slower reaction times, and impaired daytime alertness. Countermeasures to allow crew members to obtain an adequate amount of sleep and maintain adequate levels of neurobehavioral performance are being developed and investigated. However, it is necessary to develop methods that allow effective and attainable in-flight monitoring of vigilance to evaluate the effectiveness of these countermeasures and to detect and predict online critical decrements in alertness/performance. There is growing evidence to indicate that sleep loss and associated decrements in neurobehavioral function are reflected in the spectral composition of the electroencephalogram (EEG) during wakefulness as well as in the incidence of slow eye movements recorded by the electro-oculogram (EOG). Further-more, our preliminary data indicated that these changes in the EEG during wakefulness are more pronounced when subjects are in a supine posture, which mimics some of the physiologic effects of microgravity. Therefore, we evaluate the following hypotheses: (1) that during a 40-hour period of wakefulness (i.e., one night of total sleep deprivation) neurobehavioral function deteriorates, the incidence of slow eye-movements and EEG power density in the theta frequencies increases especially in frontal areas of the brain; (2) that the sleep deprivation induced deterioration of neurobehavioral function and changes in the incidence of slow eye movements and the spectral composition of the EEG are more pronounced when subjects are in a supine

  11. Wrist display concept demonstration based on 2-in. color AMOLED

    Science.gov (United States)

    Meyer, Frederick M.; Longo, Sam J.; Hopper, Darrel G.

    2004-09-01

    The wrist watch needs an upgrade. Recent advances in optoelectronics, microelectronics, and communication theory have established a technology base that now make the multimedia Dick Tracy watch attainable during the next decade. As a first step towards stuffing the functionality of an entire personnel computer (PC) and television receiver under a watch face, we have set a goal of providing wrist video capability to warfighters. Commercial sector work on the wrist form factor already includes all the functionality of a personal digital assistant (PDA) and full PC operating system. Our strategy is to leverage these commercial developments. In this paper we describe our use of a 2.2 in. diagonal color active matrix light emitting diode (AMOLED) device as a wrist-mounted display (WMD) to present either full motion video or computer generated graphical image formats.

  12. Kinematics of Hooke universal joint robot wrists

    Science.gov (United States)

    Mckinney, William S., Jr.

    1988-01-01

    The singularity problem associated with wrist mechanisms commonly found on industrial manipulators can be alleviated by redesigning the wrist so that it functions as a three-axis gimbal system. This paper discussess the kinematics of gimbal robot wrists made of one and two Hooke universal joints. Derivations of the resolved rate motion control equations for the single and double Hooke universal joint wrists are presented using the three-axis gimbal system as a theoretical wrist model.

  13. Coordination of the maize transcriptome by a conserved circadian clock

    Directory of Open Access Journals (Sweden)

    Harmon Frank G

    2010-06-01

    Full Text Available Abstract Background The plant circadian clock orchestrates 24-hour rhythms in internal physiological processes to coordinate these activities with daily and seasonal changes in the environment. The circadian clock has a profound impact on many aspects of plant growth and development, including biomass accumulation and flowering time. Despite recent advances in understanding the circadian system of the model plant Arabidopsis thaliana, the contribution of the circadian oscillator to important agronomic traits in Zea mays and other cereals remains poorly defined. To address this deficit, this study investigated the transcriptional landscape of the maize circadian system. Results Since transcriptional regulation is a fundamental aspect of circadian systems, genes exhibiting circadian expression were identified in the sequenced maize inbred B73. Of the over 13,000 transcripts examined, approximately 10 percent displayed circadian expression patterns. The majority of cycling genes had peak expression at subjective dawn and dusk, similar to other plant circadian systems. The maize circadian clock organized co-regulation of genes participating in fundamental physiological processes, including photosynthesis, carbohydrate metabolism, cell wall biogenesis, and phytohormone biosynthesis pathways. Conclusions Circadian regulation of the maize genome was widespread and key genes in several major metabolic pathways had circadian expression waveforms. The maize circadian clock coordinated transcription to be coincident with oncoming day or night, which was consistent with the circadian oscillator acting to prepare the plant for these major recurring environmental changes. These findings highlighted the multiple processes in maize plants under circadian regulation and, as a result, provided insight into the important contribution this regulatory system makes to agronomic traits in maize and potentially other C4 plant species.

  14. Ulnar Neuropathy at the Wrist

    OpenAIRE

    Pearce, Carisa; Feinberg, Joseph; Wolfe, Scott W.

    2009-01-01

    A case of ulnar nerve compression at the wrist within Guyon’s canal is reported. The clinical presentation initially appeared consistent with an ulnar nerve entrapment at the elbow. The true diagnosis of an ulnar sensorimotor nerve lesion occurring within the canal of Guyon was made electrophysiologically. Magnetic resonance imaging demonstrated compression of the nerve within the canal by a ganglionic cyst, which was confirmed by surgical intervention. Ulnar nerve entrapment at the wrist is ...

  15. Small Business Innovations (Robotic Wrist)

    Science.gov (United States)

    1991-01-01

    Under a Langley Research Center Small Business Innovation Research (SBIR) contract, Ross-Hime Designs, Inc. Minneapolis, MN, developed the Omni-Wrist actuator, which has a 25-pound capacity, 180 degrees of pitch/yaw, and 360 degrees of roll. Company literature calls it "the first successful singularity-free high-precision (robotic) wrist." Applications include spray painting, sealing, ultrasonic testing, welding and a variety of nuclear industry, aerospace and military uses.

  16. Circadian Clock Regulates Bone Resorption in Mice.

    Science.gov (United States)

    Xu, Cheng; Ochi, Hiroki; Fukuda, Toru; Sato, Shingo; Sunamura, Satoko; Takarada, Takeshi; Hinoi, Eiichi; Okawa, Atsushi; Takeda, Shu

    2016-07-01

    The circadian clock controls many behavioral and physiological processes beyond daily rhythms. Circadian dysfunction increases the risk of cancer, obesity, and cardiovascular and metabolic diseases. Although clinical studies have shown that bone resorption is controlled by circadian rhythm, as indicated by diurnal variations in bone resorption, the molecular mechanism of circadian clock-dependent bone resorption remains unknown. To clarify the role of circadian rhythm in bone resorption, aryl hydrocarbon receptor nuclear translocator-like (Bmal1), a prototype circadian gene, was knocked out specifically in osteoclasts. Osteoclast-specific Bmal1-knockout mice showed a high bone mass phenotype due to reduced osteoclast differentiation. A cell-based assay revealed that BMAL1 upregulated nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1 (Nfatc1) transcription through its binding to an E-box element located on the Nfatc1 promoter in cooperation with circadian locomotor output cycles kaput (CLOCK), a heterodimer partner of BMAL1. Moreover, steroid receptor coactivator (SRC) family members were shown to interact with and upregulate BMAL1:CLOCK transcriptional activity. Collectively, these data suggest that bone resorption is controlled by osteoclastic BMAL1 through interactions with the SRC family and binding to the Nfatc1 promoter. © 2016 American Society for Bone and Mineral Research. PMID:26841172

  17. Consequences of manganese intoxication on the circadian rest-activity rhythms in the rat.

    Science.gov (United States)

    Bouabid, Safa; Fifel, Karim; Benazzouz, Abdelhamid; Lakhdar-Ghazal, Nouria

    2016-09-01

    Manganese (Mn) intoxication is associated with neurological dysfunctions collectively known as Parkinsonism or Manganism. Like in Parkinson's disease, Manganism is associated with motor disturbances, together with non-motor symptoms including cognitive and neuropsychiatric deficits. Although sleep dysfunctions are commonly reported among workers exposed to Mn, their underlying pathophysiology remains unknown. In this study, we investigated the rest-activity rhythms in rats treated daily with MnCl2 (10mg/kg, i.p) for 5weeks. Locomotor activity was assessed under a light-dark (LD) cycle, constant darkness (DD) and during adjustment to 6h shifts of the LD cycle. In LD conditions, Mn-treated rats exhibited a more fragmented and less stable rest-activity rhythm in addition to a reduction in the total 24-h amount of locomotor activity as well as in the activity confined to the active dark phase of the LD. Consequently, a significant decrease in the amplitude of the rest-activity rhythm was observed. These disturbances were displayed during and after Mn treatment. Furthermore, after the 6-h phase advance of the LD cycle, Mn-treated rats failed to re-adjust accurately their behavioral activity to the new shifted LD cycle. Upon release from LD into DD, Mn-treated rats expressed a normal and stable free-running period of their rest-activity rhythm (23.92±0.07h in Mn group vs. 24.01±0.04h in control rats). However, their rest-activity rhythm remained highly fragmented and less stable. Our results provide the first evidence that chronic Mn intoxication leads to impairment of rest-activity rhythms in addition to the motor and non-motor disturbances reported in Manganism. PMID:27316552

  18. Nonphotic entrainment of the human circadian pacemaker

    Science.gov (United States)

    Klerman, E. B.; Rimmer, D. W.; Dijk, D. J.; Kronauer, R. E.; Rizzo, J. F. 3rd; Czeisler, C. A.

    1998-01-01

    In organisms as diverse as single-celled algae and humans, light is the primary stimulus mediating entrainment of the circadian biological clock. Reports that some totally blind individuals appear entrained to the 24-h day have suggested that nonphotic stimuli may also be effective circadian synchronizers in humans, although the nonphotic stimuli are probably comparatively weak synchronizers, because the circadian rhythms of many totally blind individuals "free run" even when they maintain a 24-h activity-rest schedule. To investigate entrainment by nonphotic synchronizers, we studied the endogenous circadian melatonin and core body temperature rhythms of 15 totally blind subjects who lacked conscious light perception and exhibited no suppression of plasma melatonin in response to ocular bright-light exposure. Nine of these fifteen blind individuals were able to maintain synchronization to the 24-h day, albeit often at an atypical phase angle of entrainment. Nonphotic stimuli also synchronized the endogenous circadian rhythms of a totally blind individual to a non-24-h schedule while living in constant near darkness. We conclude that nonphotic stimuli can entrain the human circadian pacemaker in some individuals lacking ocular circadian photoreception.

  19. Circadian influences on myocardial infarction.

    Science.gov (United States)

    Virag, Jitka A I; Lust, Robert M

    2014-01-01

    Components of circadian rhythm maintenance, or "clock genes," are endogenous entrainable oscillations of about 24 h that regulate biological processes and are found in the suprachaismatic nucleus (SCN) and many peripheral tissues, including the heart. They are influenced by external cues, or Zeitgebers, such as light and heat, and can influence such diverse phenomena as cytokine expression immune cells, metabolic activity of cardiac myocytes, and vasodilator regulation by vascular endothelial cells. While it is known that the central master clock in the SCN synchronizes peripheral physiologic rhythms, the mechanisms by which the information is transmitted are complex and may include hormonal, metabolic, and neuronal inputs. Whether circadian patterns are causally related to the observed periodicity of events, or whether they are simply epi-phenomena is not well established, but a few studies suggest that the circadian effects likely are real in their impact on myocardial infarct incidence. Cycle disturbances may be harbingers of predisposition and subsequent response to acute and chronic cardiac injury, and identifying the complex interactions of circadian rhythms and myocardial infarction may provide insights into possible preventative and therapeutic strategies for susceptible populations. PMID:25400588

  20. Circadian rhythms of women with fibromyalgia

    Science.gov (United States)

    Klerman, E. B.; Goldenberg, D. L.; Brown, E. N.; Maliszewski, A. M.; Adler, G. K.

    2001-01-01

    Fibromyalgia syndrome is a chronic and debilitating disorder characterized by widespread nonarticular musculoskeletal pain whose etiology is unknown. Many of the symptoms of this syndrome, including difficulty sleeping, fatigue, malaise, myalgias, gastrointestinal complaints, and decreased cognitive function, are similar to those observed in individuals whose circadian pacemaker is abnormally aligned with their sleep-wake schedule or with local environmental time. Abnormalities in melatonin and cortisol, two hormones whose secretion is strongly influenced by the circadian pacemaker, have been reported in women with fibromyalgia. We studied the circadian rhythms of 10 women with fibromyalgia and 12 control healthy women. The protocol controlled factors known to affect markers of the circadian system, including light levels, posture, sleep-wake state, meals, and activity. The timing of the events in the protocol were calculated relative to the habitual sleep-wake schedule of each individual subject. Under these conditions, we found no significant difference between the women with fibromyalgia and control women in the circadian amplitude or phase of rhythms of melatonin, cortisol, and core body temperature. The average circadian phases expressed in hours posthabitual bedtime for women with and without fibromyalgia were 3:43 +/- 0:19 and 3:46 +/- 0:13, respectively, for melatonin; 10:13 +/- 0:23 and 10:32 +/- 0:20, respectively for cortisol; and 5:19 +/- 0:19 and 4:57 +/- 0:33, respectively, for core body temperature phases. Both groups of women had similar circadian rhythms in self-reported alertness. Although pain and stiffness were significantly increased in women with fibromyalgia compared with healthy women, there were no circadian rhythms in either parameter. We suggest that abnormalities in circadian rhythmicity are not a primary cause of fibromyalgia or its symptoms.

  1. Sleep and circadian rhythm disruption in schizophrenia†

    OpenAIRE

    Wulff, Katharina; Dijk, Derk-Jan; Middleton, Benita; Foster, Russell G.; Joyce, Eileen M.

    2012-01-01

    Background Sleep disturbances comparable with insomnia occur in up to 80% of people with schizophrenia, but very little is known about the contribution of circadian coordination to these prevalent disruptions. Aims A systematic exploration of circadian time patterns in individuals with schizophrenia with recurrent sleep disruption. Method We examined the relationship between sleep-wake activity, recorded actigraphically over 6 weeks, along with ambient light exposure and simultaneous circadia...

  2. Circadian Clock Proteins in Mood Regulation

    OpenAIRE

    Partonen, Timo

    2015-01-01

    Mood regulation is known to be affected by the change of seasons. Recent research findings have suggested that mood regulation may be influenced by the function of circadian clocks. In addition, the activity of brown adipocytes has been hypothesized to contribute to mood regulation. Here, the overarching link to mood disorders might be the circadian clock protein nuclear receptor subfamily 1, group D, member 1.

  3. Circadian Rhythms and Obesity in Mammals

    OpenAIRE

    Oren Froy

    2012-01-01

    Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating the circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabol...

  4. Circadian clock proteins in mood regulation

    Directory of Open Access Journals (Sweden)

    Timo ePartonen

    2015-01-01

    Full Text Available Mood regulation is known to be affected by the change of seasons. Recent research findings have suggested that mood regulation may be influenced by the function of circadian clocks. In addition, the activity of brown adipocytes has been hypothesized to contribute to mood regulation. Here, the overarching link to mood disorders might be the circadian clock protein NR1D1 (nuclear receptor subfamily 1, group D, member 1.

  5. A contribution to the deterministic modelling of circadian rhythms in cell proliferation activity

    OpenAIRE

    Nieto, M; Álvarez Cabal, Ramón; Hacar Benítez, Miguel Ángel; Alarcón Álvarez, Enrique

    1987-01-01

    This paper presents a deterministic continuous model of proliferative cell activity. The classical series of connected compartments is revisited along with a simple mathematical treatment of two hypotheses: constant transit times and harmonic Ts. Several examples are presented to support these ideas, both taken from previous literature and recent experiences with the fish Carassius auratus, developed at the Junta de Energía Nuclear, Madrid, Spain.

  6. Current concepts in wrist arthroscopy.

    Science.gov (United States)

    Chloros, George D; Wiesler, Ethan R; Poehling, Gary G

    2008-03-01

    The purpose of this article is to review the recent literature on arthroscopic treatment of distal radius fractures (DRFs), triangular fibrocartilage complex injuries, intercarpal ligament injuries, and ganglion cysts, including the use of electrothermal devices. A major advantage of arthroscopy in the treatment of DRFs is the accurate assessment of the status of the articular surfaces and the detection of concomitant injuries. Nonrandomized studies of arthroscopically assisted reduction of DRFs show satisfactory results, but there is only 1 prospective randomized study showing the benefits of arthroscopy compared with open reduction-internal fixation. Wrist arthroscopy plays an important role as part of the treatment for DRFs; however, the treatment for each practitioner and each patient needs to be individualized. Wrist arthroscopy is the gold standard in the diagnosis and treatment of triangular fibrocartilage complex injuries. Type 1A injuries may be successfully treated with debridement, whereas the repair of type 1B, 1C, and 1D injuries gives satisfactory results. For type 2 injuries, the arthroscopic wafer procedure is equally effective as ulnar shortening osteotomy but is associated with fewer complications in the ulnar positive wrist. With interosseous ligament injuries, arthroscopic visualization provides critical diagnostic value. Debridement and pinning in the acute setting of complete ligament tears are promising and proven. In the chronic patient, arthroscopy can guide reconstructive options based on cartilage integrity. The preliminary results of wrist arthroscopy using electrothermal devices are encouraging; however, complications have been reported, and therefore, their use is controversial. In dorsal wrist ganglia, arthroscopy has shown excellent results, a lower rate of recurrence, and no incidence of scapholunate interosseous ligament instability compared with open ganglionectomy. Arthroscopy in the treatment of volar wrist ganglia has yielded

  7. Proximal Row Carpectomy Combined with Wrist Hemiarthroplasty

    OpenAIRE

    Culp, Randall W.; Bachoura, Abdo; Gelman, Scott E.; Jacoby, Sidney M.

    2012-01-01

    Proximal row carpectomy (PRC) combined with distal radius hemiarthroplasty is a relatively novel procedure that rivals total wrist arthrodesis and offers a new surgical treatment option for select patients with painful, end-stage wrist disease. We present our early experience with this procedure. A retrospective chart review was conducted for nonrheumatoid patients diagnosed with wrist arthritis and subsequently treated with wrist hemiarthroplasty combined with PRC. The minimum follow-up dura...

  8. The destructive wrist arthropathy of pseudogout

    International Nuclear Information System (INIS)

    The wrist is a frequent site of arthropathy in the pseudogout syndrome (calcium pyrophosphate dihydrate crystal deposition disease). Three cases of severe wrist arthropathy are presented to emphasize the destructive changes which may occur, including necrosis or collapse of the lunate and navicular bones. The roentgenographic findings characteristic of pseudogout in the wrist are discussed. (orig.)

  9. Computational Biomechanics of the Wrist Joint

    CERN Document Server

    Nazri Bajuri, Mohd

    2013-01-01

    This book presents an analysis of the stress distribution and contact stresses in severe rheumatoid wrist after total wrist arthroplasty. It assesses and compares the load transfer throughout the joint and contact pressure at the articulations. The data obtained from this study is of importance as this provide greater evidence to the benefits of total wrist arthroplasty in rheumatoid arthritis patients.

  10. Nogo-A-deficient Transgenic Rats Show Deficits in Higher Cognitive Functions, Decreased Anxiety, and Altered Circadian Activity Patterns

    Czech Academy of Sciences Publication Activity Database

    Petrásek, Tomáš; Prokopová, Iva; Sládek, Martin; Weissová, Kamila; Vojtěchová, Iveta; Bahník, Štěpán; Zemanová, Anna; Schönig, K.; Berger, S.; Tews, B.; Bartsch, D.; Schwab, M. E.; Sumová, Alena; Stuchlík, Aleš

    2014-01-01

    Roč. 8, Mar 18 (2014), s. 90. ISSN 1662-5153 R&D Projects: GA MZd(CZ) NT13386 Grant ostatní: Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M200111204; Univerzita Karlova(CZ) 365911 Institutional support: RVO:67985823 Keywords : behavior * Nogo-A * circadian system * learning * memory Subject RIV: FH - Neurology Impact factor: 3.270, year: 2014

  11. Circadian Clock Genes: Effects on Dopamine, Reward and Addiction

    OpenAIRE

    Parekh, Puja K.; Ozburn, Angela R; McClung, Colleen A.

    2015-01-01

    Addiction is a widespread public health issue with social and economic ramifications. Substance abuse disorders are often accompanied by disruptions in circadian rhythms including sleep/wake cycles, which can exacerbate symptoms of addiction and dependence. Additionally, genetic disturbance of circadian molecular mechanisms can predispose some individuals to substance abuse disorders. In this review, we will discuss how circadian genes can regulate midbrain dopaminergic activity and subsequen...

  12. Prediction of Energy Expenditure from Wrist Accelerometry in People with and without Down Syndrome

    Science.gov (United States)

    Agiovlasitis, Stamatis; Motl, Robert W.; Foley, John T.; Fernhall, Bo

    2012-01-01

    This study examined the relationship between energy expenditure and wrist accelerometer output during walking in persons with and without Down syndrome (DS). Energy expenditure in metabolic equivalent units (METs) and activity-count rate were respectively measured with portable spirometry and a uniaxial wrist accelerometer in 17 persons with DS…

  13. Neuroimaging, cognition, light and circadian rhythms

    Directory of Open Access Journals (Sweden)

    Giulia eGaggioni

    2014-07-01

    Full Text Available In humans, sleep and wakefulness and the associated cognitive processes are regulated through interactions between sleep homeostasis and the circadian system. Chronic disruption of sleep and circadian rhythmicity is common in our society and there is a need for a better understanding of the brain mechanisms regulating sleep, wakefulness and associated cognitive processes. This review summarizes recent investigations which provide first neural correlates of the combined influence of sleep homeostasis and circadian rhythmicity on cognitive brain activity. Markers of interindividual variations in sleep-wake regulation, such as chronotype and polymorphisms in sleep and clock genes, are associated with changes in cognitive brain responses in subcortical and cortical areas in response to manipulations of the sleep-wake cycle. This review also includes recent data showing that cognitive brain activity is regulated by light, which is a powerful modulator of cognition and alertness and also directly impacts sleep and circadian rhythmicity. The effect of light varied with age, psychiatric status, PERIOD3 genotype and changes in sleep homeostasis and circadian phase. These data provide new insights into the contribution of demographic characteristics, the sleep-wake cycle, circadian rhythmicity and light to brain functioning.

  14. New advances in wrist arthroscopy.

    Science.gov (United States)

    Bain, Gregory I; Munt, Justin; Turner, Perry C

    2008-03-01

    Wrist arthroscopy is a commonly used procedure that has undergone many modifications and improvements since it was first described. The advent of new portals (both dorsal and volar) means that the wrist joint can be viewed from virtually any perspective ("box concept"). Indications for wrist arthroscopy have continued to expand and include diagnostic and reparative procedures and, more recently, reconstructive, soft-tissue, and bony procedures. Arthroscopic grading of Kienböck's disease better describes articular damage compared with plain radiographs and can help guide surgical treatment options. Triangular fibrocartilage complex injury diagnosis, classification, and treatment can be performed arthroscopically, including distal ulna resection (wafer procedure). Assessment of fracture reduction of the distal radius and scaphoid is superior to that obtained with fluoroscopy, with the advantage of being able to look for associated soft-tissue and chondral injuries. Arthroscopic assessment of intercarpal ligament injuries and instability is now considered the gold standard by many authors. Arthroscopy can also aid us in the management of post-traumatic capsular contraction, resection of ganglia, and the relatively rare isolated ulna styloid impaction. Complications of wrist arthroscopy are relatively uncommon. With the ever-expanding list of indications and procedures that can be performed with this technique, it exists as an essential diagnostic and therapeutic tool for the orthopaedic surgeon. PMID:18308189

  15. Suprachiasmatic nuclei and Circadian rhythms. The role of suprachiasmatic nuclei on rhythmic activity of neurons in the lateral hypothalamic area, ventromedian nuclei and pineal gland

    Science.gov (United States)

    Nishino, H.

    1977-01-01

    Unit activity of lateral hypothalamic area (LHA) and Ventromedian nuclei (VMN) was recorded in urethane anesthetized male rats. A 5 to 10 sec. a 3-5 min and a circadian rhythmicity were observed. In about 15% of all neurons, spontaneous activity of LHA and VMN showed reciprocal relationships. Subthreshold stimuli applied at a slow rate in the septum and the suprachiasmatic nuclei (SCN) suppressed the rhythms without changing firing rates. On the other hand, stimulation of the optic nerve at a rate of 5 to 10/sec increased firing rates in 1/3 of neurons of SCN. Iontophoretically applied acetylcholine increased 80% of tested neurons of SCN, whereas norepinephrine, dopamine and 5 HT inhibited 64, 60 and 75% of SCN neurons respectively. These inhibitions were much stronger in neurons, the activity of which was increased by optic nerve stimulation. Stimulation of the SCN inhibited the tonic activity in cervical sympathetic nerves.

  16. Circadian Organization of Behavior and Physiology in Drosophila

    Science.gov (United States)

    Allada, Ravi; Chung, Brian Y.

    2010-01-01

    Circadian clocks organize behavior and physiology to adapt to daily environmental cycles. Genetic approaches in the fruit fly, Drosophila melanogaster, have revealed widely conserved molecular gears of these 24-h timers. Yet much less is known about how these cell-autonomous clocks confer temporal information to modulate cellular functions. Here we discuss our current knowledge of circadian clock function in Drosophila, providing an overview of the molecular underpinnings of circadian clocks. We then describe the neural network important for circadian rhythms of locomotor activity, including how these molecular clocks might influence neuronal function. Finally, we address a range of behaviors and physiological systems regulated by circadian clocks, including discussion of specific peripheral oscillators and key molecular effectors where they have been described. These studies reveal a remarkable complexity to circadian pathways in this “simple” model organism. PMID:20148690

  17. Circadian influences on myocardial infarction

    OpenAIRE

    Virag, Jitka A. I.; Lust, Robert M.

    2014-01-01

    Components of circadian rhythm maintenance, or “clock genes,” are endogenous entrainable oscillations of about 24 h that regulate biological processes and are found in the suprachaismatic nucleus (SCN) and many peripheral tissues, including the heart. They are influenced by external cues, or Zeitgebers, such as light and heat, and can influence such diverse phenomena as cytokine expression immune cells, metabolic activity of cardiac myocytes, and vasodilator regulation by vascular endothelial...

  18. Effects of chronic expression of the HIV-induced protein, transactivator of transcription, on circadian activity rhythms in mice, with or without morphine

    OpenAIRE

    Duncan, Marilyn J.; Bruce-Keller, Annadora J.; Conner, Clayton; Knapp, Pamela E.; Xu, Ruquiang; Nath, Avindra; Hauser, Kurt F.

    2008-01-01

    Patients with human immunodeficiency virus (HIV) infection exhibit changes in sleep patterns, motor disorders, and cognitive dysfunction; these symptoms may be secondary to circadian rhythm abnormalities. Studies in mice have shown that intracerebral injection of an HIV protein, transactivator of transcription (Tat), alters the timing of circadian rhythms in a manner similar to light. Therefore, we tested the hypothesis that chronic Tat expression alters circadian rhythms, especially their en...

  19. Profiling molecular and behavioral circadian rhythms in the non-symbiotic sea anemone Nematostella vectensis

    OpenAIRE

    Oren, Matan; Tarrant, Ann M.; Alon, Shahar; Simon-Blecher, Noa; Elbaz, Idan; Appelbaum, Lior; Levy, Oren

    2015-01-01

    Endogenous circadian clocks are poorly understood within early-diverging animal lineages. We have characterized circadian behavioral patterns and identified potential components of the circadian clock in the starlet sea anemone, Nematostella vectensis: a model cnidarian which lacks algal symbionts. Using automatic video tracking we showed that Nematostella exhibits rhythmic circadian locomotor activity, which is persistent in constant dark, shifted or disrupted by external dark/light cues and...

  20. NPAS2 Compensates for Loss of CLOCK in Peripheral Circadian Oscillators

    OpenAIRE

    Landgraf, Dominic; Wang, Lexie L.; Diemer, Tanja; Welsh, David K.

    2016-01-01

    Heterodimers of CLOCK and BMAL1 are the major transcriptional activators of the mammalian circadian clock. Because the paralog NPAS2 can substitute for CLOCK in the suprachiasmatic nucleus (SCN), the master circadian pacemaker, CLOCK-deficient mice maintain circadian rhythms in behavior and in tissues in vivo. However, when isolated from the SCN, CLOCK-deficient peripheral tissues are reportedly arrhythmic, suggesting a fundamental difference in circadian clock function between SCN and periph...

  1. Dissociation of Ultradian and Circadian Phenotypes in Female and Male Siberian Hamsters

    OpenAIRE

    Prendergast, Brian J.; Cisse, Yasmine M.; Cable, Erin J.; Zucker, Irving

    2012-01-01

    Three experiments addressed whether pronounced alterations in the circadian system yielded concomitant changes in ultradian timing. Female Siberian hamsters were housed in a 16L:8D photoperiod after being subjected to a disruptive phase-shifting protocol that produced 3 distinct permanent circadian phenotypes: some hamsters entrained their circadian rhythms (CRs) with predominantly nocturnal locomotor activity (ENTR), others displayed free-running CRs (FR), and a third cohort was circadian ar...

  2. Denervation of the wrist joint.

    Science.gov (United States)

    Buck-Gramcko, D

    1977-01-01

    A collective review was made of the results of denervation of the wrist joint for painful restrictiorn of motion done in 313 patients and follow-up studies on 195 (average 4.1 years, ranging from 9 months to 14 years). Complete denervation was done in only 30, partial denervation in the others being done after testing with local anesthetic blocks. Sixty-nine of the patients retained a moble wrist without pain or with slight pain with heavy work. No evidence of Charcot-like joints was seen. Poorest results followed when the operation was done for sequelae of intra-articular fracture of the radius, fracture dislocations, unstable ligamentous support, joint surface destruction, or for those required to do heavy manual labor. Arthrodesis was done secondarily in nine patients. PMID:839055

  3. Circadian clock genes universally control key agricultural traits

    Science.gov (United States)

    Circadian clocks are endogenous timers that enable plants to synchronize biological processes with daily and seasonal environmental conditions in order to allocate resources during the most beneficial times of day and year. The circadian clock regulates a number of central plant activities, includin...

  4. Bidirectional Interactions between Circadian Entrainment and Cognitive Performance

    Science.gov (United States)

    Gritton, Howard J.; Kantorowski, Ana; Sarter, Martin; Lee, Theresa M.

    2012-01-01

    Circadian rhythms influence a variety of physiological and behavioral processes; however, little is known about how circadian rhythms interact with the organisms' ability to acquire and retain information about their environment. These experiments tested whether rats trained outside their endogenous active period demonstrate the same rate of…

  5. Synergistic interactions between the molecular and neuronal circadian networks drive robust behavioral circadian rhythms in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Ron Weiss

    2014-04-01

    Full Text Available Most organisms use 24-hr circadian clocks to keep temporal order and anticipate daily environmental changes. In Drosophila melanogaster CLOCK (CLK and CYCLE (CYC initiates the circadian system by promoting rhythmic transcription of hundreds of genes. However, it is still not clear whether high amplitude transcriptional oscillations are essential for circadian timekeeping. In order to address this issue, we generated flies in which the amplitude of CLK-driven transcription can be reduced partially (approx. 60% or strongly (90% without affecting the average levels of CLK-target genes. The impaired transcriptional oscillations lead to low amplitude protein oscillations that were not sufficient to drive outputs of peripheral oscillators. However, circadian rhythms in locomotor activity were resistant to partial reduction in transcriptional and protein oscillations. We found that the resilience of the brain oscillator is depending on the neuronal communication among circadian neurons in the brain. Indeed, the capacity of the brain oscillator to overcome low amplitude transcriptional oscillations depends on the action of the neuropeptide PDF and on the pdf-expressing cells having equal or higher amplitude of molecular rhythms than the rest of the circadian neuronal groups in the fly brain. Therefore, our work reveals the importance of high amplitude transcriptional oscillations for cell-autonomous circadian timekeeping. Moreover, we demonstrate that the circadian neuronal network is an essential buffering system that protects against changes in circadian transcription in the brain.

  6. Ganglions of the hand and wrist.

    Science.gov (United States)

    Thornburg, L E

    1999-01-01

    Ganglions of the hand and wrist are common benign lesions. They most frequently arise adjacent to joints and tendons, but may also be intratendinous or intraosseous. Treatment options include observation, aspiration, and surgical excision. Observation is acceptable in most instances. Indications for more aggressive treatment include pain, interference with activity, nerve compression, and imminent ulceration (in the case of some mucous cysts). The recurrence rate after puncture and aspiration is greater than 50% for cysts in most locations, but is less than 30% for cysts in the flexor tendon sheath. Surgical excision is effective, with a recurrence rate of only 5% if care is taken to completely excise the stalk of the cyst along with a small portion of joint capsule. Surgical treatment of occult ganglions is successful with accurate assessment of the source of the pain. Arthroscopic treatment of dorsal wrist ganglions is still experimental, but early results are encouraging. Ganglion surgery requires a formal operative environment and careful technique in order to minimize injury to adjacent structures and minimize the likelihood of recurrence. PMID:10434077

  7. Circadian Misalignment and Health

    OpenAIRE

    Baron, Kelly Glazer; Reid, Kathryn J.

    2014-01-01

    Circadian rhythms are near 24-hour patterns of physiology and behavior that are present independent of external cues including hormones, body temperature, mood, and sleep propensity. The term “circadian misalignment” describes a variety of circumstances, such as inappropriately timed sleep and wake, misalignment of sleep/wake with feeding rhythms, or misaligned central and peripheral rhythms. The predominance of early research focused on misalignment of sleep to the biological night. However,...

  8. The anatomy and pathophysiology of the wrist.

    Science.gov (United States)

    Hooper, Geoffrey

    2006-04-28

    A basic knowledge of the anatomy and the interrelationships of the structures that make up the joint is a prerequisite for understanding the pathomechanics of the wrist. In the paper, the anatomy (especially including carpal ligaments) and the mechanics of wrist movements, also under load, are described. The features of the common wrist disorders that occur as a result of injury are also explained. PMID:17603435

  9. Can total wrist arthroplasty be an option in the treatment of the severely destroyed posttraumatic wrist?

    DEFF Research Database (Denmark)

    Boeckstyns, Michel E H; Herzberg, Guillaume; Sørensen, Allan Ibsen;

    2013-01-01

    Background Severely destroyed posttraumatic wrists are usually treated by partial or total wrist fusion or proximal row carpectomy. The indications for and longevity of total wrist arthroplasty (TWA) are still unclear. Case Description The aim of this study was to analyze a series in which one la...

  10. Circadian rhythms and fractal fluctuations in forearm motion

    Science.gov (United States)

    Hu, Kun; Hilton, Michael F.

    2005-03-01

    Recent studies have shown that the circadian pacemaker --- an internal body clock located in the brain which is normally synchronized with the sleep/wake behavioral cycles --- influences key physiologic functions such as the body temperature, hormone secretion and heart rate. Surprisingly, no previous studies have investigated whether the circadian pacemaker impacts human motor activity --- a fundamental physiologic function. We investigate high-frequency actigraph recordings of forearm motion from a group of young and healthy subjects during a forced desynchrony protocol which allows to decouple the sleep/wake cycles from the endogenous circadian cycle while controlling scheduled behaviors. We investigate both static properties (mean value, standard deviation), dynamical characteristics (long-range correlations), and nonlinear features (magnitude and Fourier-phase correlations) in the fluctuations of forearm acceleration across different circadian phases. We demonstrate that while the static properties exhibit significant circadian rhythms with a broad peak in the afternoon, the dynamical and nonlinear characteristics remain invariant with circadian phase. This finding suggests an intrinsic multi-scale dynamic regulation of forearm motion the mechanism of which is not influenced by the circadian pacemaker, thus suggesting that increased cardiac risk in the early morning hours is not related to circadian-mediated influences on motor activity.

  11. Carpal instability of the wrist.

    Science.gov (United States)

    Caggiano, Nicholas; Matullo, Kristofer S

    2014-01-01

    The scaphoid is stabilized by the scapholunate ligament (directly) and lunotriquetral ligament (indirectly). Disruption of either of these ligaments leads to a pattern of instability that, left untreated, leads to altered mechanics of the wrist and ultimately debilitating arthritis and collapse. Although arthroscopy remains the gold standard for diagnosis of these injuries, plain films and advanced imaging are useful adjuncts. In the acute setting, conservative treatment may be attempted, but recalcitrant cases require surgical stabilization. Salvage procedures are also available for those patients who fail initial stabilization or present with late degeneration. PMID:24267214

  12. Tendon involvement in rheumatoid arthritis of the wrist: MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Valeri, G.; Ferrara, C.; Ercolani, P.; De Nigris, E. [Ancona Univ. (Italy). Dept. of Radiology; Giovagnoni, A. [Modena Univ. (Italy). Dept. of Radiology

    2001-03-01

    Objective. To evaluate the distribution and extent of wrist tendon alterations in patients with active rheumatoid arthritis (RA) using magnetic resonance imaging (MRI). Design and patients. Forty-three clinically active RA patients with an illness duration of less than 4 years and no clinical evidence of tendons tears were enrolled in the study. There were 10 men and 33 women, with an average age of 52 years (range 33-63 years). MRI of both wrists, with one exception, was performed at 1.0 T using T1- and T2-weighted sequences (slice thickness 3 mm). Twelve healthy subjects (8 women, 4 men; mean age 31 years) were also evaluated as a control group. Two radiologists reviewed each of four schematic anatomical regions (volar, dorsal, ulnar, radial) for the degree of tendon and tendon sheath alterations using two progressive scales. Results. In the control group all tendons had homogeneous low signal intensity on all sequences. A small amount of fluid was found in six subjects but the diameter was always less than 1 mm. In the patient group minimal fluid (<2 mm) was found in 35 (41%) wrists, grade 2 fluid (<2>5mm) in 26 (31%) and grade 3 fluid (>5 mm) in 24 (28%). Fiftynine (69%) of the grade 1 changes were in the volar compartment but grade 2 involvement was evenly distributed. Grade 3 changes were most common in the dorsal compartment and combined grade 2 and 3 in the dorsal and ulnar compartments were 32 (38%) and 25 (30%) compared with 16 (18%) and 17 (20%) respectively in the volar and radial compartments. The tendons were normal (grade 0) in 47 (46%) wrists. A maximum tendon signal change (grade 1) was demonstrated in 28 wrists (32%). When associated with other individual tendons grades this grade was demonstrated in the dorsal compartment in 30 (35%) wrists, in the volar compartment in 12 (14%), in the radial compartment in 17 (20%) and in the ulnar compartment in 26 (30%). A partial tear (grade 2) was detected in 7 (8%) wrists, all involving the dorsal and ulnar

  13. Circadian rhythm sleep disorders

    Directory of Open Access Journals (Sweden)

    Morgenthaler TI

    2012-05-01

    Full Text Available Bhanu P Kolla,1,2 R Robert Auger,1,2 Timothy I Morgenthaler11Mayo Center for Sleep Medicine, 2Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USAAbstract: Misalignment between endogenous circadian rhythms and the light/dark cycle can result in pathological disturbances in the form of erratic sleep timing (irregular sleep–wake rhythm, complete dissociation from the light/dark cycle (circadian rhythm sleep disorder, free-running type, delayed sleep timing (delayed sleep phase disorder, or advanced sleep timing (advanced sleep phase disorder. Whereas these four conditions are thought to involve predominantly intrinsic mechanisms, circadian dysrhythmias can also be induced by exogenous challenges, such as those imposed by extreme work schedules or rapid transmeridian travel, which overwhelm the ability of the master clock to entrain with commensurate rapidity, and in turn impair approximation to a desired sleep schedule, as evidenced by the shift work and jet lag sleep disorders. This review will focus on etiological underpinnings, clinical assessments, and evidence-based treatment options for circadian rhythm sleep disorders. Topics are subcategorized when applicable, and if sufficient data exist. The length of text associated with each disorder reflects the abundance of associated literature, complexity of management, overlap of methods for assessment and treatment, and the expected prevalence of each condition within general medical practice.Keywords: circadian rhythm sleep disorders, assessment, treatment

  14. Current innovations in wrist arthroscopy.

    Science.gov (United States)

    Slutsky, David J

    2012-09-01

    It has become clear that the stability of the scapholunate joint does not depend wholly on the scapholunate interosseous ligament, but rather on both primary and secondary stabilizers, which form a scapholunate ligament complex. Each case of scapholunate instability is unique and should be treated with tissue-specific repairs, which may partly explain why one procedure cannot successfully restore joint stability in every case. Wrist arthroscopy has a pivotal role in both the assessment and treatment of the scapholunate ligament complex derangements. Tears of the foveal attachment of the triangular fibrocartilaginous complex can be an underdiagnosed cause of distal radioulnar joint instability, because the foveal fibers cannot be visualized using the standard radiocarpal arthroscopy portals. Distal radioulnar joint arthroscopy allows for direct visualization and assessment of these fibers, which in turn has spawned a number of open and arthroscopic repair methods. Wrist arthroscopy has gained wider acceptance as a method to fine-tune articular reduction during open and percutaneous fixation of distal radius fractures, and simplifies intra-articular osteotomies for malunion. It can facilitate percutaneous bone grafting of scaphoid nonunions and has a role in the diagnosis and treatment of associated soft tissue lesions. These and other recent developments will be discussed in the following article. PMID:22916867

  15. The effect of forearm posture on wrist flexion in computer workers with chronic upper extremity musculoskeletal disorders

    Directory of Open Access Journals (Sweden)

    Thompson R Terry

    2008-04-01

    Full Text Available Abstract Background Occupational computer use has been associated with upper extremity musculoskeletal disorders (UEMSDs, but the etiology and pathophysiology of some of these disorders are poorly understood. Various theories attribute the symptoms to biomechanical and/or psychosocial stressors. The results of several clinical studies suggest that elevated antagonist muscle tension may be a biomechanical stress factor. Affected computer users often exhibit limited wrist range of motion, particularly wrist flexion, which has been attributed to increased extensor muscle tension, rather than to pain symptoms. Recreational or domestic activities requiring extremes of wrist flexion may produce injurious stress on the wrist joint and muscles, the symptoms of which are then exacerbated by computer use. As these activities may involve a variety of forearm postures, we examined whether changes in forearm posture have an effect on pain reports during wrist flexion, or whether pain would have a limiting effect on flexion angle. Methods We measured maximum active wrist flexion using a goniometer with the forearm supported in the prone, neutral, and supine postures. Data was obtained from 5 subjects with UEMSDs attributed to computer use and from 13 control subjects. Results The UEMSD group exhibited significantly restricted wrist flexion compared to the control group in both wrists at all forearm postures with the exception of the non-dominant wrist with the forearm prone. In both groups, maximum active wrist flexion decreased at the supine forearm posture compared to the prone posture. No UEMSD subjects reported an increase in pain symptoms during testing. Conclusion The UEMSD group exhibited reduced wrist flexion compared to controls that did not appear to be pain related. A supine forearm posture reduced wrist flexion in both groups, but the reduction was approximately 100% greater in the UEMSD group. The effect of a supine forearm posture on wrist

  16. Flexible and static wrist units in upper limb prosthesis users : functionality scores, user satisfaction and compensatory movements

    NARCIS (Netherlands)

    Deijs, Marieke; Bongers, R. M.; Ringeling-van Leusen, N. D. M.; van der Sluis, C. K.

    2016-01-01

    Background: The current study examines the relevance of prosthetic wrist movement to facilitate activities of daily living or to prevent overuse complaints. Prosthesis hands with wrist flexion/extension capabilities are commercially available, but research on the users' experiences with flexible wri

  17. Combined pre-injection wrist and ankle MRI protocol and steroid joint injections in juvenile idiopathic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Kan, J.H. [Texas Children' s Hospital, Department of Radiology, Houston, TX (United States); Graham, T.B. [Monroe Carell Jr. Children' s Hospital at Vanderbilt, Department of Pediatric Rheumatology, Nashville, TN (United States)

    2011-10-15

    Precise localization of affected compartments of the wrist and ankle in children with an established diagnosis of juvenile idiopathic arthritis (JIA) is clinically challenging. The purpose of this paper is to describe our experience utilizing a pre-injection MRI protocol of the wrist and ankle for localizing disease activity followed by fluoroscopically guided joint injections in children with JIA. (orig.)

  18. How Temperature Changes Reset a Circadian Oscillator

    NARCIS (Netherlands)

    Merrow, Martha; Loros, Jennifer J.; Dunlap, Jay C.

    1998-01-01

    Circadian rhythms control many physiological activities. The environmental entrainment of rhythms involves the immediate responses of clock components. Levels of the clock protein FRQ were measured in Neurospora at various temperatures; at higher temperatures, the amount of FRQ oscillated around hig

  19. Circadian Clocks, Stress, and Immunity

    Science.gov (United States)

    Dumbell, Rebecca; Matveeva, Olga; Oster, Henrik

    2016-01-01

    In mammals, molecular circadian clocks are present in most cells of the body, and this circadian network plays an important role in synchronizing physiological processes and behaviors to the appropriate time of day. The hypothalamic–pituitary–adrenal endocrine axis regulates the response to acute and chronic stress, acting through its final effectors – glucocorticoids – released from the adrenal cortex. Glucocorticoid secretion, characterized by its circadian rhythm, has an important role in synchronizing peripheral clocks and rhythms downstream of the master circadian pacemaker in the suprachiasmatic nucleus. Finally, glucocorticoids are powerfully anti-inflammatory, and recent work has implicated the circadian clock in various aspects and cells of the immune system, suggesting a tight interplay of stress and circadian systems in the regulation of immunity. This mini-review summarizes our current understanding of the role of the circadian clock network in both the HPA axis and the immune system, and discusses their interactions. PMID:27199894

  20. The promoter activities of sucrose phosphate synthase genes in rice, OsSPS1 and OsSPS11, are controlled by light and circadian clock, but not by sucrose

    Directory of Open Access Journals (Sweden)

    Madoka eYonekura

    2013-03-01

    Full Text Available Although sucrose plays a role in sugar sensing and its signaling pathway, little is known about the regulatory mechanisms of the expressions of plant sucrose-related genes. Our previous study on the expression of the sucrose phosphate synthase gene family in rice (OsSPSs suggested the involvement of sucrose sensing and/or circadian rhythm in the transcriptional regulation of OsSPS. To examine whether the promoters of OsSPSs can be controlled by sugars and circadian clock, we produced transgenic rice plants harboring a promoter–luciferase construct for OsSPS1 or OsSPS11 and analyzed the changes in the promoter activities by monitoring bioluminescence from intact transgenic plants in real time. Transgenic plants fed sucrose, glucose, or mannitol under continuous light conditions showed no changes in bioluminescence intensity; meanwhile, the addition of sucrose increased the concentration of sucrose in the plants, and the mRNA levels of OsSPS remained constant. These results suggest that these OsSPS promoters may not be regulated by sucrose levels in the tissues. Next, we investigated the changes in the promoter activities under 12-h light/12-h dark cycles and continuous light conditions. Under the light–dark cycle, both OsSPS1 and OsSPS11 promoter activities were low in the dark and increased rapidly after the beginning of the light period. When the transgenic rice plants were moved to the continuous light condition, both POsSPS1::LUC and POsSPS11::LUC reporter plants exhibited circadian bioluminescence rhythms; bioluminescence peaked during the subjective day with a 27-h period: in the early morning as for OsSPS1 promoter and midday for OsSPS11 promoter. These results indicate that these OsSPS promoters are controlled by both light illumination and circadian clock and that the regulatory mechanism of promoter activity differs between the 2 OsSPS genes.

  1. Biological Clocks & Circadian Rhythms

    Science.gov (United States)

    Robertson, Laura; Jones, M. Gail

    2009-01-01

    The study of biological clocks and circadian rhythms is an excellent way to address the inquiry strand in the National Science Education Standards (NSES) (NRC 1996). Students can study these everyday phenomena by designing experiments, gathering and analyzing data, and generating new experiments. As students explore biological clocks and circadian…

  2. Hand/Wrist Disorders among Sign Language Communicators.

    Science.gov (United States)

    Smith, Susan M.; Kress, Tyler A.; Hart, William M.

    2000-01-01

    A study assessed the frequency of self-reported hand/wrist problems among 184 sign-language communicators. Fifty-nine percent reported experiencing hand/wrist problems, 26 percent reported experiencing hand/wrist problems severe enough to limit their ability to work, and 18 percent reported a medical diagnosis of wrist tendinitis, carpal tunnel…

  3. Prognosis of wrist ganglion operations.

    Science.gov (United States)

    Gündeş, H; Cirpici, Y; Sarlak, A; Müezzinoglu, S

    2000-10-01

    A retrospective study was conducted to evaluate the results of treatment of 40 wrist ganglia operated under local anesthesia over four years. The mean follow-up period was 27 months (range 6-48 months). There were 24 dorsal and 16 volar ganglia. The mean complication rate was 56% for volar ganglia, 12.5% for dorsal ganglia, and the difference was significant (p dorsal cyst) and to the palmar cutaneous branch of the median nerve in two patients (volar cysts). The mean nerve injury rate was 7.5%. In two patients with volar ganglia, the palmar superficial branch of the radial artery was lace-rated and had to be ligated. The significantly higher complication rate after excision of volar ganglia in contrast to dorsal ones might indicate that the former should be approached more carefully in contrast to dorsal ones and preferably by a senior surgeon. PMID:11103488

  4. Arthroscopic findings in patients with painful wrist ganglia.

    Science.gov (United States)

    Povlsen, B; Peckett, W R

    2001-09-01

    The aetiology of painful dorsal wrist ganglia remains obscure. In a prospective study we investigated the link between a painful dorsal wrist ganglion and wrist joint abnormality with wrist arthroscopy before excision of the ganglion. Of 16 wrists arthroscoped 12 were abnormal, 10 had an abnormal scapholunate joint, and two had abnormal lunatetriquetral joints. We think that painful dorsal wrist ganglia, like popliteal cysts in the knee, are markers of underlying joint abnormalities. Surgeons who treat painful ganglia should be aware of a possible underlying cause so that they can target treatment more accurately, particularly in recurrent cases and those patients with persistent wrist pain after excision of the ganglion. PMID:11680404

  5. Tendon involvement in rheumatoid arthritis of the wrist: MRI findings

    International Nuclear Information System (INIS)

    Objective. To evaluate the distribution and extent of wrist tendon alterations in patients with active rheumatoid arthritis (RA) using magnetic resonance imaging (MRI). Design and patients. Forty-three clinically active RA patients with an illness duration of less than 4 years and no clinical evidence of tendons tears were enrolled in the study. There were 10 men and 33 women, with an average age of 52 years (range 33-63 years). MRI of both wrists, with one exception, was performed at 1.0 T using T1- and T2-weighted sequences (slice thickness 3 mm). Twelve healthy subjects (8 women, 4 men; mean age 31 years) were also evaluated as a control group. Two radiologists reviewed each of four schematic anatomical regions (volar, dorsal, ulnar, radial) for the degree of tendon and tendon sheath alterations using two progressive scales. Results. In the control group all tendons had homogeneous low signal intensity on all sequences. A small amount of fluid was found in six subjects but the diameter was always less than 1 mm. In the patient group minimal fluid (5mm) in 26 (31%) and grade 3 fluid (>5 mm) in 24 (28%). Fiftynine (69%) of the grade 1 changes were in the volar compartment but grade 2 involvement was evenly distributed. Grade 3 changes were most common in the dorsal compartment and combined grade 2 and 3 in the dorsal and ulnar compartments were 32 (38%) and 25 (30%) compared with 16 (18%) and 17 (20%) respectively in the volar and radial compartments. The tendons were normal (grade 0) in 47 (46%) wrists. A maximum tendon signal change (grade 1) was demonstrated in 28 wrists (32%). When associated with other individual tendons grades this grade was demonstrated in the dorsal compartment in 30 (35%) wrists, in the volar compartment in 12 (14%), in the radial compartment in 17 (20%) and in the ulnar compartment in 26 (30%). A partial tear (grade 2) was detected in 7 (8%) wrists, all involving the dorsal and ulnar compartments; five underwent surgical repair and one

  6. Forward and inverse kinematics of double universal joint robot wrists

    Science.gov (United States)

    Williams, Robert L., II

    1991-01-01

    A robot wrist consisting of two universal joints can eliminate the wrist singularity problem found on many individual robots. Forward and inverse position and velocity kinematics are presented for such a wrist having three degrees of freedom. Denavit-Hartenberg parameters are derived to find the transforms required for the kinematic equations. The Omni-Wrist, a commercial double universal joint robot wrist, is studied in detail. There are four levels of kinematic parameters identified for this wrist; three forward and three inverse maps are presented for both position and velocity. These equations relate the hand coordinate frame to the wrist base frame. They are sufficient for control of the wrist standing alone. When the wrist is attached to a manipulator arm; the offset between the two universal joints complicates the solution of the overall kinematics problem. All wrist coordinate frame origins are not coincident, which prevents decoupling of position and orientation for manipulator inverse kinematics.

  7. Circadian profile of cardiac autonomic nervous modulation in healthy subjects

    DEFF Research Database (Denmark)

    Bonnemeier, Hendrik; Richardt, Gert; Potratz, Jürgen;

    2003-01-01

    , awoke around 7 A.M., and had 6 to 8 hours of sleep. Circadian profiles of vagus-associated HRV parameters revealed a marked day-night pattern, with a peak at nighttime and a plateau at daytime. The characteristic nocturnal peak and the day-night amplitude diminished with aging by decade. Estimates of......UNLABELLED: Circadian Profile of Heart Rate Variability. INTRODUCTION: Although heart rate variability (HRV) has been established as a tool to study cardiac autonomic activity, almost no data are available on the circadian patterns of HRV in healthy subjects aged 20 to 70 years. METHODS AND RESULTS...

  8. Osteoarthritis of the Wrist STT Joint and Radiocarpal Joint

    OpenAIRE

    Ronit Wollstein; Julio Clavijo; Gilula, Louis A.

    2012-01-01

    Our understanding of wrist osteoarthritis (OA) lags behind that of other joints, possibly due to the complexity of wrist biomechanics and the importance of ligamentous forces in the function of the wrist. Scaphotrapeziotrapezoidal (STT) OA is common, but its role in wrist clinical pathology and biomechanics is unclear. We identified the prevalence of radiographic STT joint OA in our hand clinic population and defined the relationship between STT and radiocarpal OA in wrist radiographs. One hu...

  9. Flight Schedule and the Circadian Clock Influence on Sleep Loss During Overnight Cargo Operations

    Science.gov (United States)

    Gander, Philippa H.; Gregory, Kevin B.; Rosekind, Mark R.; Shafto, Michael G. (Technical Monitor)

    1995-01-01

    Thirty-four flight crew members were monitored before, during, and after two 8-day overnight cargo duty patterns which involved multiple flights at night crossing no more than one time zone per 24 h. Rectal temperature, heart rate, and wrist activity were recorded every 2 min. Sleep quantity and quality, and nap timing, were noted in a logbook. To reduce the masking effects of physical activity on temperature, 0.28 C was added to each subject's raw temperature data whenever he reported being asleep. For both masked and unmasked data, daily temperature minima were estimated from the multiple complex demodulated waveform. The temperature minima did not show a progressive adaptation to night duty, which was interrupted by a night off after 5 nights on one trip pattern and after 3 nights on the other. On duty days, the average temperature minimum delayed by about 3 h, occurring near the end of the duty period. Daytime sleep episodes averaged 2.9 h shorter than nighttime sleep episodes, and were rated as lighter, less restorative, and poorer overall. Fifty-three percent of subjects slept more than once per 24 h while they were on night duty, compared to 17% when able to sleep at night. The total sleep per 24 h on duty days averaged 1.2 h less than pretrip. Twenty-nine percent of subjects lost more than 2 h of sleep per 24 h across the 8-day duty patterns. After night duty, subjects awoke around 1400 local time, even when they had slept 2-3 h less than a normal nocturnal sleep episode. Consequently, the duration of morning sleep episodes was correlated with the off-duty time (multiple r(sup 2)=0.44, F=37.23, p less than 0.0001). Anecdotally, crew members complained of being unable to sleep longer and not feeling well-rested. These wakeups were clustered 6 h after the temperature minimum, which suggests that they may have been a response to the circadian wakeup signal. Daytime layovers in which crew members were able to sleep again in the evening ended later (0200

  10. Bilateral three-compartment wrist arthrography in patients with unilateral wrist pain: findings and implications for management

    International Nuclear Information System (INIS)

    Bilateral three-compartment wrist arthrography was performed in 30 patients with unilateral post-traumatic wrist pain to assess the incidence of bilateral findings. The mean age of patients was 30 (range 18-55) years. Thirty-three percent of patients were normal bilaterally, 30% had unilateral communication in the symptomatic wrist, 30% had communications in both the symptomatic and asymptomatic wrists and 7% had communication in the asymptomatic wrist only. Unilateral three-compartment wrist arthrography is not recommended in the assessment of unilateral post-traumatic wrist pain; no advantage of three-compartment injection over radiocarpal injection alone was shown. (orig.)

  11. Ganglion Cyst of the Wrist and Hand

    Science.gov (United States)

    .org Ganglion Cyst of the Wrist and Hand Page ( 1 ) Ganglion cysts are the most common mass or lump ... can quickly appear, disappear, and change size. Many ganglion cysts do not require treatment. However, if the ...

  12. Wrist arthroscopy: principles and clinical applications.

    Science.gov (United States)

    Gupta, R; Bozentka, D J; Osterman, A L

    2001-01-01

    With the development of better and smaller equipment, arthroscopy of the wrist offers the same benefits achievable with arthroscopy of the knee, shoulder, or elbow - not only diagnostic information but also a therapeutic option. Standardized techniques of performing wrist arthroscopy have been developed to evaluate the treat various wrist disorders, such as lesions of the triangular fibrocartilage complex, intra-articular distal radius fractures, and scaphoid fractures. Arthroscopy is now performed in the treatment of dorsal-wrist ganglion cysts and interosseous ligament disruptions, as well as for bone incisions, such as radial styloidectomy, distal ulnar excision (wafer procedure), and proximal-row carpectomy. Compared with other techniques, arthroscopic procedures, such as repair of the triangular fibrocartilage complex, demonstrate better results and improved localization of the injury with a low complication rate. In addition, arthroscopic procedures involve lesssurgical dissection, less postoperative pain, a shorter recovery time, and an earlier return to work for the patient. PMID:11421577

  13. Temperature compensation and entrainment in circadian rhythms

    International Nuclear Information System (INIS)

    To anticipate daily variations in the environment and coordinate biological activities into a daily cycle many organisms possess a circadian clock. In the absence of external time cues the circadian rhythm persists with a period of approximately 24 h. The clock phase can be shifted by single pulses of light, darkness, chemicals, or temperature and this allows entrainment of the clock to exactly 24 h by cycles of these zeitgebers. On the other hand, the period of the circadian rhythm is kept relatively constant within a physiological range of constant temperatures, which means that the oscillator is temperature compensated. The mechanisms behind temperature compensation and temperature entrainment are not fully understood, neither biochemically nor mathematically. Here, we theoretically investigate the interplay of temperature compensation and entrainment in general oscillatory systems. We first give an analytical treatment for small temperature shifts and derive that every temperature-compensated oscillator is entrainable to external small-amplitude temperature cycles. Temperature compensation ensures that this entrainment region is always centered at the endogenous period regardless of possible seasonal temperature differences. Moreover, for small temperature cycles the entrainment region of the oscillator is potentially larger for rectangular pulses. For large temperature shifts we numerically analyze different circadian clock models proposed in the literature with respect to these properties. We observe that for such large temperature shifts sinusoidal or gradual temperature cycles allow a larger entrainment region than rectangular cycles. (paper)

  14. Ganglions of the hand and wrist.

    Science.gov (United States)

    Young, L; Bartell, T; Logan, S E

    1988-06-01

    The ganglion is the most common soft tissue tumor of the hand and wrist, originating from the joint capsule or tendon sheath. Accurate diagnosis and proper treatment of these entities require a thorough knowledge of the anatomy of the wrist and hand as well as of the ganglion itself. Definitive therapy is based on total surgical removal of the cyst and its connections to the joint or tendon sheath. PMID:3287641

  15. The Smart Home Controller on Your Wrist

    OpenAIRE

    De Russis, Luigi; Bonino, Dario; Corno, Fulvio

    2013-01-01

    This paper addresses human-home interaction mediated by everyday objects, with a particular focus on wrist watches. Everyday wrist-worn devices are turned into flexible home access points by exploiting a modular architecture independent from the underlying home automation system, and from the specific watch device, provided that the necessary capabilities are available. A first working prototype based on a cost-effective consumer watch is presented, and experimental results confirm the viabil...

  16. Circadian Role in Daily Pattern of Cardiovascular Risk

    Science.gov (United States)

    Ivanov, Plamen Ch.; Hu, Kun; Chen, Zhi; Hilton, Michael F.; Stanley, H. Eugene; Shea, Steven A.

    2004-03-01

    Numerous epidemiological studies demonstrate that sudden cardiac death, pulmonary embolism, myocardial infarction, and stroke have a 24-hour daily pattern with a broad peak between 9-11am. Such a daily pattern in cardiovascular risk could be attributable to external factors, such as the daily behavior patterns, including sleep-wake cycles and activity levels, or internal factors, such as the endogenous circadian pacemaker. Findings of significant alternations in the temporal organization and nonlinear properties of heartbeat fluctuations with disease and with sleep-wake transitions raise the intriguing possibility that changes in the mechanism of control associated with behavioral sleep-wake transition may be responsible for the increased cardiac instability observed in particular circadian phases. Alternatively, we hypothesize that there is a circadian clock, independent of the sleep-wake cycle, which affects the cardiac dynamics leading to increased cardiovascular risk. We analyzed continuous recordings from healthy subjects during 7 cycles of forced desynchrony routine wherein subjects' sleep-wake cycles are adjusted to 28 hours so that their behaviors occur across all circadian phases. Heartbeat data were divided into one-hour segments. For each segment, we estimated the correlations and the nonlinear properties of the heartbeat fluctuations at the corresponding circadian phase. Since the sleep and wake contributions are equally weighted in our experiment, a change of the properties of the heartbeat dynamics with circadian phase suggest a circadian rhythm. We show significant circadian-mediated alterations in the correlation and nonlinear properties of the heartbeat resembling those observed in patients with heart failure. Remarkably, these dynamical alterations are centered at 60 degrees circadian phase, coinciding with the 9-11am window of cardiac risk.

  17. Circadian adaptations to meal timing: Neuroendocrine mechanisms

    Directory of Open Access Journals (Sweden)

    Danica F Patton

    2013-10-01

    Full Text Available Circadian rhythms of behavior and physiology are generated by central and peripheral circadian oscillators entrained by periodic environmental or physiological stimuli. A master circadian pacemaker in the hypothalamic suprachiasmatic nucleus is directly entrained by daily light-dark cycles, and coordinates the timing of other oscillators by direct and indirect neural, hormonal and behavioral outputs. The daily rhythm of food intake provides stimuli that entrain most peripheral and central oscillators, some of which can drive a daily rhythm of food anticipatory activity if food is restricted to one daily mealtime. The location of food-entrainable oscillators (FEOs that drive food anticipatory rhythms, and the food-related stimuli that entrain these oscillators, remain to be clarified. Here, we critically examine the role of peripheral metabolic hormones as potential internal entrainment stimuli or outputs for FEOs controlling food anticipatory rhythms in rats and mice. Hormones for which data are available include corticosterone, ghrelin, leptin, insulin, glucagon, and glucagon-like peptide 1. All of these hormones exhibit daily rhythms of synthesis and secretion that are synchronized by meal timing. There is some evidence that ghrelin and leptin modulate the expression of food anticipatory rhythms, but none of the hormones examined so far are necessary for entrainment. Ghrelin and leptin likely modulate food-entrained rhythms by actions in hypothalamic circuits utilizing melanocortin and orexin signaling, although again food-entrained behavioral rhythms can persist in lesion and gene knockout models in which these systems are disabled. Actions of these hormones on circadian oscillators in central reward circuits remain to be evaluated. Food-entrained activity rhythms are likely mediated by a distributed system of circadian oscillators sensitive to multiple feeding related inputs. Metabolic hormones appear to play a modulatory role within this

  18. Chromatin Dynamics of Circadian Transcription

    OpenAIRE

    Aguilar-Arnal, Lorena; Sassone-Corsi, Paolo

    2015-01-01

    The molecular circadian clock orchestrates the daily cyclical expression of thousands of genes. Disruption of this transcriptional program leads to a variety of pathologies, including insomnia, depression and metabolic disorders. Circadian rhythms in gene expression rely on specific chromatin transitions which are ultimately coordinated by the molecular clock. As a consequence, a highly plastic and dynamic circadian epigenome can be delineated across different tissues and cell types. Intrigui...

  19. MR and CT arthrography of the wrist.

    Science.gov (United States)

    Cerezal, Luis; de Dios Berná-Mestre, Juan; Canga, Ana; Llopis, Eva; Rolon, Alejandro; Martín-Oliva, Xavier; del Piñal, Francisco

    2012-02-01

    The study of the wrist represents a major diagnostic challenge because of its complex anatomy and the small size of individual structures. Recent advances in imaging techniques have increased our diagnostic capabilities. However, 3T magnets, multichannel specific wrist coils, and new MRI sequences have not restricted the indications of arthrographic imaging techniques (CT arthrography and MR arthrography). Distension of the different wrist compartments at CT arthrography and MR arthrography significantly improves the diagnostic accuracy for triangular fibrocartilage (TFC) complex injuries and carpal instability. Dedicated multichannel wrist coils are essential for an adequate study of the wrist, but the placement of these coils and the positioning of the wrist are also important for proper diagnosis. The development of dynamic multislice CT studies allows a diagnostic approach that combines dynamic information and the accurate assessment of ligaments and the TFC complex. New advances in arthroscopy have changed the anatomical description of the TFC with a functional division in the proximal and distal TFC complex, and they have allowed a better characterization of lesions of the TFC complex with subclassification of Palmer 1B and 1D lesions and description of new lesions not included in the Palmer classification, such as capsular injuries. PMID:22447235

  20. CCL2 mediates the circadian response to low dose endotoxin.

    Science.gov (United States)

    Duhart, José M; Brocardo, Lucila; Mul Fedele, Malena L; Guglielmotti, Angelo; Golombek, Diego A

    2016-09-01

    The mammalian circadian system is mainly originated in a master oscillator located in the suprachiasmatic nuclei (SCN) in the hypothalamus. Previous reports from our and other groups have shown that the SCN are sensitive to systemic immune activation during the early night, through a mechanism that relies on the action of proinflammatory factors within this structure. Chemokine (C-C motif) ligand 2 (CCL2) is induced in the brain upon peripheral immune activation, and it has been shown to modulate neuronal physiology. In the present work we tested whether CCL2 might be involved in the response of the circadian clock to peripheral endotoxin administration. The CCL2 receptor, C-C chemokine receptor type 2 (CCR2), was detected in the SCN of mice, with higher levels of expression during the early night, when the clock is sensitive to immune activation. Ccl2 was induced in the SCN upon intraperitoneal lipopolysaccharide (LPS) administration. Furthermore, mice receiving an intracerebroventricular (Icv) administration of a CCL2 synthesis inhibitor (Bindarit), showed a reduction LPS-induced circadian phase changes and Icv delivery of CCL2 led to phase delays in the circadian clock. In addition, we tested the possibility that CCL2 might also be involved in the photic regulation of the clock. Icv administration of Bindarit did not modify the effects of light pulses on the circadian clock. In summary, we found that CCL2, acting at the SCN level is important for the circadian effects of immune activation. PMID:27178133

  1. Automatic Segmentation of Wrist Bones in CT Using a Statistical Wrist Shape + Pose Model.

    Science.gov (United States)

    Anas, Emran Mohammad Abu; Rasoulian, Abtin; Seitel, Alexander; Darras, Kathryn; Wilson, David; John, Paul St; Pichora, David; Mousavi, Parvin; Rohling, Robert; Abolmaesumi, Purang

    2016-08-01

    Segmentation of the wrist bones in CT images has been frequently used in different clinical applications including arthritis evaluation, bone age assessment and image-guided interventions. The major challenges include non-uniformity and spongy textures of the bone tissue as well as narrow inter-bone spaces. In this work, we propose an automatic wrist bone segmentation technique for CT images based on a statistical model that captures the shape and pose variations of the wrist joint across 60 example wrists at nine different wrist positions. To establish the correspondences across the training shapes at neutral positions, the wrist bone surfaces are jointly aligned using a group-wise registration framework based on a Gaussian Mixture Model. Principal component analysis is then used to determine the major modes of shape variations. The variations in poses not only across the population but also across different wrist positions are incorporated in two pose models. An intra-subject pose model is developed by utilizing the similarity transforms at all wrist positions across the population. Further, an inter-subject pose model is used to model the pose variations across different wrist positions. For segmentation of the wrist bones in CT images, the developed model is registered to the edge point cloud extracted from the CT volume through an expectation maximization based probabilistic approach. Residual registration errors are corrected by application of a non-rigid registration technique. We validate the proposed segmentation method by registering the wrist model to a total of 66 unseen CT volumes of average voxel size of 0.38 mm. We report a mean surface distance error of 0.33 mm and a mean Jaccard index of 0.86. PMID:26890640

  2. Ulnar sided wrist pain and distal radioulnar joint osteoarthritis; is surgical arthroplasty enough?

    Directory of Open Access Journals (Sweden)

    Ronit Wollstein

    2012-05-01

    Full Text Available Distal radioulnar joint (DRUJ arthritis is a common cause of ulnar wrist pain in rheumatoid and osteoarthritis. Modified arthroplasty for the DRUJ is a minimally invasive procedure for the treatment of isolated DRUJ osteoarthritis. The purpose of this study was to evaluate the efficacy of the procedure and the incidence of related ulnar wrist pathology as well as the incidence of subsequent ulnar wrist surgeries. All patients having modified arthroplasty for the DRUJ between 1994-2008 were retrospectively reviewed. Measurements included range of motion, grip strength, and subjective status. Data regarding other wrist surgeries was recorded. There were 29 patients, 23 of which had a follow-up of over 8 weeks (average 16 months (SD=24. Fourteen patients had no to minimal pain, 6 had pain with heavier activities (2 severe, and 2 reported constant pain at the surgical site. Of the 4 more painful patients, three had additional surgery after the DRUJ arthroplasty. In all 96% of the patients had another procedure involving the ulnar- wrist complex either prior to surgery, at the time of surgery or following surgery for modified arthroplasty. We suggest that pathology involving the ulnar-wrist complex is often a syndrome consisting of multiple related diagnoses including but not limited to arthritis of the DRUJ. Multiple procedures may be needed, or a more aggressive approach such as ulnar head replacement may be indicated so that pathology at both the distal radioulnar and ulnocarpal joints is addressed concomitantly.

  3. Evaluation of wrist arthroscopy outcomes in patients with chronic wrist pain

    Directory of Open Access Journals (Sweden)

    Reza Shahryar Kamrani

    2015-01-01

    Conclusion: According to our results, wrist arthroscopy have acceptable outcome in TFCC injuries and Kienbock disease. With the ever-expanding list of indications and procedures that can be performed with wrist arthroscopy, it can be considered as an essential diagnostic and therapeutic tool for the orthopedic surgeon.

  4. The effect of lens aging and cataract surgery on circadian rhythm.

    Science.gov (United States)

    Yan, Shen-Shen; Wang, Wei

    2016-01-01

    Many organisms have evolved an approximately 24-hour circadian rhythm that allows them to achieve internal physiological homeostasis with external environment. Suprachiasmatic nucleus (SCN) is the central pacemaker of circadian rhythm, and its activity is entrained to the external light-dark cycle. The SCN controls circadian rhythm through regulating the synthesis of melatonin by pineal gland via a multisynaptic pathway. Light, especially short-wavelength blue light, is the most potent environmental time cue in circadian photoentrainment. Recently, the discovery of a novel type of retinal photoreceptors, intrinsically photosensitive retinal ganglion cells, sheds light on the mechanism of circadian photoentrainment and raises concerns about the effect of ocular diseases on circadian system. With age, light transmittance is significantly decreased due to the aging of crystalline lens, thus possibly resulting in progressive loss of circadian photoreception. In the current review, we summarize the circadian physiology, highlight the important role of light in circadian rhythm regulation, discuss about the correlation between age-related cataract and sleep disorders, and compare the effect of blue light- filtering intraocular lenses (IOLs) and ultraviolet only filtering IOLs on circadian rhythm. PMID:27500118

  5. Novel putative mechanisms to link circadian clocks to healthy aging.

    Science.gov (United States)

    Popa-Wagner, Aurel; Catalin, Bogdan; Buga, Ana-Maria

    2015-08-01

    The circadian clock coordinates the internal physiology to increase the homeostatic capacity thereby providing both a survival advantage to the system and an optimization of energy budgeting. Multiple-oscillator circadian mechanisms are likely to play a role in regulating human health and may contribute to the aging process. Our aim is to give an overview of how the central clock in the hypothalamus and peripheral clocks relate to aging and metabolic disorders, including hyperlipidemia and hyperglycemia. In particular, we unravel novel putative mechanisms to link circadian clocks to healthy aging. This review may lead to the design of large-scale interventions to help people stay healthy as they age by adjusting daily activities, such as feeding behavior, and or adaptation to age-related changes in individual circadian rhythms. PMID:24297467

  6. In vivo length changes of wrist ligaments at full wrist extension.

    Science.gov (United States)

    Tan, J; Chen, J; Tang, J B

    2014-05-01

    The aim of this study was to investigate the length changes of carpal ligaments when loaded in full extension in vivo. We obtained computed tomography scans of the right wrists in three positions for six volunteers: neutral; 75° extension; and 75° extension with a further 10° of radial deviation. Nine ligaments were measured and analysed with computer modelling. The results showed that the radioscaphocapitate, long radiolunate, and ulnolunate ligaments lengthened the most at full wrist extension, suggesting that they were under greatest load. The radioscapholunate, ulnocapitate, and ulnotriquetral ligaments lengthened further with the addition of wrist radial deviation. At full extension, the dorsal intercarpal ligament inserting on the scaphoid was lengthened. The dorsal radiocarpal and dorsal intercarpal ligaments inserting on the trapezoid were shortened, suggesting reduced loading. In conclusion, a number of volar carpal ligaments lengthened significantly in full wrist extension and the ulnar carpal ligaments were further lengthened at wrist radial deviation. PMID:23571488

  7. Circadian Rhythms of Crawling and Swimming in the Nudibranch Mollusc Melibe leonina

    OpenAIRE

    Newcomb, James M; Kirouac, Lauren E.; NAIMIE, AMANDA A.; BIXBY, KIMBERLY A.; Lee, Colin; MALANGA, STEPHANIE; RAUBACH, MAUREEN; Watson, Winsor H.

    2014-01-01

    Daily rhythms of activity driven by circadian clocks are expressed by many organisms, including molluscs. We initiated this study, with the nudibranch Melibe leonina, with four goals in mind: (1) determine which behaviors are expressed with a daily rhythm; (2) investigate which of these rhythmic behaviors are controlled by a circadian clock; (3) determine if a circadian clock is associated with the eyes or optic ganglia of Melibe, as it is in several other gastropods; and (4) test the hypothe...

  8. AMPK regulates circadian rhythms in a tissue- and isoform-specific manner.

    Directory of Open Access Journals (Sweden)

    Jee-Hyun Um

    Full Text Available BACKGROUND: AMP protein kinase (AMPK plays an important role in food intake and energy metabolism, which are synchronized to the light-dark cycle. In vitro, AMPK affects the circadian rhythm by regulating at least two clock components, CKIα and CRY1, via direct phosphorylation. However, it is not known whether the catalytic activity of AMPK actually regulates circadian rhythm in vivo. METHODOLOGY/PRINCIPAL FINDING: THE CATALYTIC SUBUNIT OF AMPK HAS TWO ISOFORMS: α1 and α2. We investigate the circadian rhythm of behavior, physiology and gene expression in AMPKα1-/- and AMPKα2-/- mice. We found that both α1-/- and α2-/- mice are able to maintain a circadian rhythm of activity in dark-dark (DD cycle, but α1-/- mice have a shorter circadian period whereas α2-/- mice showed a tendency toward a slightly longer circadian period. Furthermore, the circadian rhythm of body temperature was dampened in α1-/- mice, but not in α2-/- mice. The circadian pattern of core clock gene expression was severely disrupted in fat in α1-/- mice, but it was severely disrupted in the heart and skeletal muscle of α2-/- mice. Interestingly, other genes that showed circadian pattern of expression were dysreguated in both α1-/- and α2-/- mice. The circadian rhythm of nicotinamide phosphoryl-transferase (NAMPT activity, which converts nicotinamide (NAM to NAD+, is an important regulator of the circadian clock. We found that the NAMPT rhythm was absent in AMPK-deficient tissues and cells. CONCLUSION/SIGNIFICANCE: This study demonstrates that the catalytic activity of AMPK regulates circadian rhythm of behavior, energy metabolism and gene expression in isoform- and tissue-specific manners.

  9. Circadian organization of the mammalian retina: from gene regulation to physiology and diseases.

    Science.gov (United States)

    McMahon, Douglas G; Iuvone, P Michael; Tosini, Gianluca

    2014-03-01

    The retinal circadian system represents a unique structure. It contains a complete circadian system and thus the retina represents an ideal model to study fundamental questions of how neural circadian systems are organized and what signaling pathways are used to maintain synchrony of the different structures in the system. In addition, several studies have shown that multiple sites within the retina are capable of generating circadian oscillations. The strength of circadian clock gene expression and the emphasis of rhythmic expression are divergent across vertebrate retinas, with photoreceptors as the primary locus of rhythm generation in amphibians, while in mammals clock activity is most robust in the inner nuclear layer. Melatonin and dopamine serve as signaling molecules to entrain circadian rhythms in the retina and also in other ocular structures. Recent studies have also suggested GABA as an important component of the system that regulates retinal circadian rhythms. These transmitter-driven influences on clock molecules apparently reinforce the autonomous transcription-translation cycling of clock genes. The molecular organization of the retinal clock is similar to what has been reported for the SCN although inter-neural communication among retinal neurons that form the circadian network is apparently weaker than those present in the SCN, and it is more sensitive to genetic disruption than the central brain clock. The melatonin-dopamine system is the signaling pathway that allows the retinal circadian clock to reconfigure retinal circuits to enhance light-adapted cone-mediated visual function during the day and dark-adapted rod-mediated visual signaling at night. Additionally, the retinal circadian clock also controls circadian rhythms in disk shedding and phagocytosis, and possibly intraocular pressure. Emerging experimental data also indicate that circadian clock is also implicated in the pathogenesis of eye disease and compelling experimental data

  10. Circadian and ultradian influences on dreaming: a dual rhythm model.

    Science.gov (United States)

    Wamsley, Erin J; Hirota, Yasutaka; Tucker, Matthew A; Smith, Mark R; Antrobus, John S

    2007-01-01

    The dual rhythm model of dreaming states that, under high sensory thresholds, heightened general cortical activation common to both REM/NREM and circadian-driven activation cycles sums to produce the main characteristics of dreaming. In addition, the unique pattern of regional brain activation characteristic of REM sleep amplifies the emotional intensity of the dream. Subjects were awakened from REM and NREM sleep once near the nadir of the core body temperature rhythm, where circadian-driven cortical activation was assumed to be low, and again in the late morning, where this activation was presumed to be high. As predicted, changes in the central characteristics of dream reports mirrored REM/NREM and circadian-driven fluctuations in general activation, while at the same time, the regional activation pattern unique to REM sleep amplified dream emotionality selectively in REM reports. PMID:17208651

  11. The mood stabilizer valproic acid opposes the effects of dopamine on circadian rhythms.

    Science.gov (United States)

    Landgraf, Dominic; Joiner, William J; McCarthy, Michael J; Kiessling, Silke; Barandas, Rita; Young, Jared W; Cermakian, Nicolas; Welsh, David K

    2016-08-01

    Endogenous circadian (∼24 h) clocks regulate key physiological and cognitive processes via rhythmic expression of clock genes. The main circadian pacemaker is the hypothalamic suprachiasmatic nucleus (SCN). Mood disorders, including bipolar disorder (BD), are commonly associated with disturbed circadian rhythms. Dopamine (DA) contributes to mania in BD and has direct impact on clock gene expression. Therefore, we hypothesized that high levels of DA during episodes of mania contribute to disturbed circadian rhythms in BD. The mood stabilizer valproic acid (VPA) also affects circadian rhythms. Thus, we further hypothesized that VPA normalizes circadian disturbances caused by elevated levels of DA. To test these hypotheses, we examined locomotor rhythms and circadian gene cycling in mice with reduced expression of the dopamine transporter (DAT-KD mice), which results in elevated DA levels and mania-like behavior. We found that elevated DA signaling lengthened the circadian period of behavioral rhythms in DAT-KD mice and clock gene expression rhythms in SCN explants. In contrast, we found that VPA shortened circadian period of behavioral rhythms in DAT-KD mice and clock gene expression rhythms in SCN explants, hippocampal cell lines, and human fibroblasts from BD patients. Thus, DA and VPA have opposing effects on circadian period. To test whether the impact of VPA on circadian rhythms contributes to its behavioral effects, we fed VPA to DAT-deficient Drosophila with and without functioning circadian clocks. Consistent with our hypothesis, we found that VPA had potent activity-suppressing effects in hyperactive DAT-deficient flies with intact circadian clocks. However, these effects were attenuated in DAT-deficient flies in which circadian clocks were disrupted, suggesting that VPA functions partly through the circadian clock to suppress activity. Here, we provide in vivo and in vitro evidence across species that elevated DA signaling lengthens the circadian

  12. Magnetic resonance imaging of the wrist ligaments

    International Nuclear Information System (INIS)

    The advent of small arthroscopes has enabled the hand surgeon to visualize the ligaments of the wrist directly with resultant increased accuracy in diagnosing and treating pathology. Orthopaedists are now demanding a preoperative assessment and this, in turn, has necessitated that radiologists have a comprehensive understanding of wrist anatomy. High resolution MR imaging can identify the wrist ligaments reliably and provide information concerning their integrity. Interpretation is not straightforward; there is considerable anatomic variation, and there are perforations, defects and degenerative tears that can be troublesome in diagnosing injury. However, with experience and attention to anatomic detail, the radiologist can provide useful information regarding structural abnormalities. When injured, the ligaments of the wrist behave as other joint ligaments do. Findings following injury include discontinuity of normal striated bands, incomplete disruption, irregularities and alteration in normal signal. Fluid pooling around a ligament and concomitant bone injury are other clues to injury. The identification of such structural abnormalities may help to explain altered biomechanics and improve the management of patients following wrist injury. Copyright (2001) Blackwell Science Pty Ltd

  13. Tuberculous Tenosynovitis Presenting as Ganglion of Wrist

    Directory of Open Access Journals (Sweden)

    Shahaji Chavan

    2012-01-01

    Full Text Available Tuberculosis (TB is still endemic in many developed countries. Involvement of the hand and wrist at presentation is extremely rare, and the diagnosis is often missed. A 57 years old male presented with swelling over the left wrist since 3 years Three swellings over dorsal aspect of the left wrist Soft in consistency Non tender Non compressible Mobile at right angles to the plane of the wrist joint. ESR: 45 mm in 1 hr and rest blood investigations were normal. Ultrsonography showed giant cell tumor of Extensor Digitorum sheath. X-ray: soft tissue swelling and MRI was suggestive of extensor tendon sheath extraskeletal synovial Koch’s, or giant cell tumor of tendon sheath. Excision of swelling was planned and intraoperatively, rice bodies were seen inside it. Histopathological examination showed caseous necrosis with granuloma formation. Patient was put on DOT1 therapy. Tuberculous tenosynovitis was first described by Acrel in 1777. Rice bodies occurring in joints affected by tuberculosis were first described in 1895 by Reise. Rice bodies will be diagnosed on plain radiographs when mineralization occurs. More than 50% of cases recur within 1 year of treatment. The currently recommended 6-month course is often adequate with extensive curettage lavage and synovectomy should be performed. Surgery is essential, but the extent of surgical debridement is still debatable. The surgeon has to be aware of the significance of loose bodies when performing routine excision of innocuous looking wrist ganglia.

  14. Circadian timed wakefulness at dawn opposes compensatory sleep responses after sleep deprivation in Octodon degus

    NARCIS (Netherlands)

    Kas, M J; Edgar, D M

    1999-01-01

    The circadian timing system in mammals is thought to promote wakefulness and oppose sleep drive that accumulates across the activity phase in diurnal and nocturnal species. Whether the circadian system actively opposes compensatory sleep responses in mammals with episodes of alertness consolidated a

  15. The circadian activity rhythm of mosquitoes through men-net-bait and CO2 lamp-trapping%入帐诱与CO2灯诱对蚊蚋种群昼夜活动节律的研究

    Institute of Scientific and Technical Information of China (English)

    党荣理; 董言德; 郑重; 郭晓霞; 张映梅; 张桂林; 赵彤言

    2011-01-01

    Objective To understand the circadian activity rhythm of mosquitoes in three environments of Beiwan region through men-net-bait and C02 lamp - trapping. Methods The circadian activity rhythm of mosquitoes through men-net-bait and C02 lamp-trapping were carried out in three different environment. Results The same result were obtained as for the species and population composition between men-net-bait and C02 lamp-trapping, and Si. Mculatum showed a little more harmful than mosquito in three environments. Aedes vexans was predominant species with a proportion of over 95% , both An. Maculatum and Ae. Caspius were very few. The same circadian activity rhythm was obtained for Aedes vexans between two methods, and the circadian activity rhythm for Si. Mculatum with a complicated activity curves were very different in three environments. Conclusion Both men-net-bait and C02 lamp - trapping are available for the research on the circadian activity rhythm of mosquitoes, further studies remain to be done with using C02 lamp-trapping to investigate the circadian activity rhythm and population for blackfly.%目的 研究人帐诱法和CO2灯诱法对北湾地区蚊、蚋种群昼夜活动的变化规律.方法 选取3种不同生境同时采用入帐诱法和CO2灯诱法进行昼夜数量动态的调查.结果 2种方法对于危害种类及组成调查结果一致,在3种生境中班布蚋的危害均大于蚊虫,刺扰伊蚊为当地的优势蚊虫,组成占到95%以上,里海伊蚊和米赛按蚊数量很少;对于种群昼夜活动节律,刺扰伊蚊2种方法结果一致,都具有晨峰和昏峰,昏峰明显,数量多,晨峰数量较少,班布蚋的活动曲线较为复杂,不同生境变化较大,但一般具有4个高峰,两种方法调查结果差异较大.结论 人帐诱和CO2灯诱都可作为蚊虫种群数量及活动节律的调查方法,但对于蚋种群CO2灯诱法是否能作为数量及活动节律的调查方法,还需做进一步的研究.

  16. The circadian clock, reward and memory

    OpenAIRE

    Urs eAlbrecht

    2011-01-01

    During our daily activities, we experience variations in our cognitive performance, which is often accompanied by cravings for small rewards, such as consuming coffee or chocolate. This indicates that the time of day, cognitive performance, and reward may be related to one another. This review will summarize data that describe the influence of the circadian clock on addiction and mood-related behavior and put the data into perspective in relation to memory processes.

  17. Circadian polymorphisms associated with affective disorders

    OpenAIRE

    Kripke, Daniel F; Nievergelt, Caroline M; Joo, EJ; Shekhtman, Tatyana; Kelsoe, John R.

    2009-01-01

    Background: Clinical symptoms of affective disorders, their response to light treatment, and sensitivity to other circadian interventions indicate that the circadian system has a role in mood disorders. Possibly the mechanisms involve circadian seasonal and photoperiodic mechanisms. Since genetic susceptibilities contribute a strong component to affective disorders, we explored whether circadian gene polymorphisms were associated with affective disorders in four complementary studies.Methods:...

  18. Interaction of MAGED1 with nuclear receptors affects circadian clock function

    OpenAIRE

    Wang, Xiaohan; Tang, Jing; Xing, Lijuan; Shi, Guangsen; Ruan, Haibin; Gu, Xiwen; Liu, Zhiwei; Wu, Xi; Gao, Xiang; Xu, Ying

    2010-01-01

    The circadian clock has a central role in physiological adaption and anticipation of day/night changes. In a genetic screen for novel regulators of circadian rhythms, we found that mice lacking MAGED1 (Melanoma Antigen Family D1) exhibit a shortened period and altered rest–activity bouts. These circadian phenotypes are proposed to be caused by a direct effect on the core molecular clock network that reduces the robustness of the circadian clock. We provide in vitro and in vivo evidence indica...

  19. Wear particles and osteolysis in patients with total wrist arthroplasty

    DEFF Research Database (Denmark)

    Boeckstyns, Michel E H; Toxværd, Anders; Bansal, Manjula; Vadstrup, Lars Soelberg

    2014-01-01

    tissue, the level of chrome and cobalt ions in the blood, and the possible role of infectious or rheumatoid activity in the development of PPO. METHODS: Biopsies were taken from the implant-bone interphase in 13 consecutive patients with total wrist arthroplasty and with at least 3 years' follow...... of the radiolucent zone. The blood levels of chrome and cobalt ions were normal. There was no evidence of infectious or rheumatoid activity. CONCLUSIONS: Polyethylene wear has been accepted as a major cause of osteolysis in total hip arthroplasty, and metallic debris has also been cited to be an...

  20. The sublethal effects of endosulfan on the circadian rhythms and locomotor activity of two sympatric parasitoid species.

    Science.gov (United States)

    Delpuech, Jean-Marie; Bussod, Sophie; Amar, Aurelien

    2015-08-01

    The organochlorine insecticide endosulfan is dispersed worldwide and significantly contributes to environmental pollution. It is an antagonist of the neurotransmitter gamma-aminobutyric acid (GABA), which is also indirectly involved in photoperiodic time measurement. In this study, we show that endosulfan at a dose as low as LC 0.1 modified the rhythm of locomotor activity of two sympatric parasitoid species, Leptopilina boulardi and Leptopilina heterotoma. The insecticide strongly increased the nocturnal activity of both species and synchronized their diurnal activity; these activities were not synchronized under control conditions. Parasitoids are important species in ecosystems because they control the populations of other insects. In this paper, we discuss the possible consequences of these sublethal effects and highlight the importance of such effects in evaluating the consequences of environmental pollution due to insecticides. PMID:25898969

  1. [Arthroscopic resection of dorsal wrist ganglia].

    Science.gov (United States)

    Borisch, N

    2014-10-01

    In arthroscopic wrist surgery, the resection of dorsal wrist ganglia has become a well accepted practice. As advantages for the minimally invasive procedure the low complication rate and low postoperative morbidity, less postoperative pain and faster recovery over open techniques are discussed. The possibility to assess accompanying joint pathology is considered as another advantage. The importance of identifying a so-called ganglion cyst stalk seems to have been overstated. Regarding the technique, the main discussion points are the size and localisation of the capsular window and the necessity of additional midcarpal arthroscopy. The possibility and results of treatment of recurrent ganglion cysts are still controversial. Our own experience and that of some authors are positive. Hardly mentioned in the literature is the treatment of occult dorsal wrist ganglia and its results, which is considered as very successful by the authors. PMID:25290273

  2. Ultrasonography of the hand, wrist, and elbow.

    Science.gov (United States)

    Bodor, Marko; Fullerton, Brad

    2010-08-01

    High-frequency diagnostic ultrasonography of the hand, wrist and elbow has significant potential to improve the quality of diagnosis and care provided by neuromuscular and musculoskeletal specialists. In patients referred for weakness, pain and numbness of the hand, wrist or elbow, diagnostic ultrasonography can be an adjunct to electrodiagnosis and help in identifying ruptured tendons and treating conditions such as carpal tunnel syndrome or trigger finger. Use of a small high-frequency (>10-15 MHz) transducer, an instrument with a blunt pointed tip to enhance sonopalpation and a model of the hand, wrist and elbow is advised to enhance visualization of small anatomical structures and complex bony contours. A range of conditions, including tendon and ligament ruptures, trigger finger, de Quervain tenosynovitis, intersection syndrome, lateral epicondylitis, and osteoarthritis, is described along with detailed ultrasonography-guided injection techniques for carpal tunnel syndrome and trigger finger. PMID:20797547

  3. CMYB1 Encoding a MYB Transcriptional Activator Is Involved in Abiotic Stress and Circadian Rhythm in Rice

    Directory of Open Access Journals (Sweden)

    Min Duan

    2014-01-01

    Full Text Available Through analysis of cold-induced transcriptome, a novel gene encoding a putative MYB transcription factor was isolated and designated Cold induced MYB 1 (CMYB1. Tissue-specific gene expression analysis revealed that CMYB1 was highly expressed in rice stems and nodes. qRT-PCR assay indicated that CMYB1 was dramatically induced by cold stress (>100-folds and induced by exogenous ABA and osmotic stress. Interestingly, CMYB1 showed rhythmic expression profile in rice leaves at different developmental stages. Subcellular localization assay suggested that CMYB1-GFP (green fluorescent protein fusion protein was localized in the nuclei. Moreover, CMYB1 exhibited the transcriptional activation activity when transiently expressed in rice protoplast cells. Taken together, CMYB1 probably functions as a transcriptional activator in mediating stress and rhythm responsive gene expression in rice.

  4. Two Case Report on Wrist Ganglion Treated with Scolopendrid Pharmacopuncture

    OpenAIRE

    Min-Seop Shin; Jin-Bok Lee; Beom-yong Song

    2010-01-01

    Object : This study was to investigate the clinical effect of Scolopendrid Pharmacopuncture on two patients suffering from Wrist Ganglion. Methods : We treated two patients suffering from Wrist Ganglion with both acupuncture and injection of Scolopendrid Pharmacopuncture. Then we measured the sizes of Wrist Ganglion and Visual Analogue Scale(VAS). Results and Conclusions : We found that the sizes of Wrist Ganglion of the two patients were significantly reduced. Moreover, the pain and di...

  5. 3D Dynamic Analysis of the Wrist.

    Science.gov (United States)

    Sandow, Michael J

    2015-10-01

    With advances in imaging and computing technology the greater capacity to diagnose, plan and deliver care to patients with hand and wrist disorder is being realised. Work in our laboratory, has been able to identify certain specific rules that control wrist motion, and is a step on the pathway to creating a unified theory of carpal mechanics which will incorporate a kinetic biomechanical model. This will allow more precise anatomically based as well as quantitative diagnoses, but also an ability to test a proposed intervention in a "what if" scenario. PMID:26387995

  6. Dorsal wrist mass: the carpal boss

    OpenAIRE

    Boggess, Blake; Berkoff, David

    2011-01-01

    The carpal boss is an osseous overgrowth that is occasionally mistaken for a ganglion cyst. This report highlights the case a 36-year-old patient who was originally diagnosed by his primary care physician with a ganglion cyst and was sent to an orthopaedist for aspiration. Upon further evaluation with a plain radiograph, the dorsal wrist mass was found to be a carpal boss. The patient was treated with rest and a wrist brace, and was informed that a corticosteroid injection or surgical excisio...

  7. Dorsal wrist ganglion: Current review of literature.

    Science.gov (United States)

    Meena, Sanjay; Gupta, Ajay

    2014-06-01

    Ganglion cyst is the most common soft tissue tumour of hand. Sixty to seventy percent of ganglion cysts are found in the dorsal aspect of the wrist. They may affect any age group; however they are more common in the twenties to forties. Its origin and pathogenesis remains enigmatic. Non-surgical treatment is unreliable with a high recurrence rates. Open surgical excision leads to unsightly scar and poor outcome. Arthroscopy excision has shown very promising result with very low recurrence rate. We reviewed the current literature available on dorsal wrist ganglion. PMID:25983472

  8. Dorsal wrist mass: the carpal boss.

    Science.gov (United States)

    Boggess, Blake; Berkoff, David

    2011-01-01

    The carpal boss is an osseous overgrowth that is occasionally mistaken for a ganglion cyst. This report highlights the case a 36-year-old patient who was originally diagnosed by his primary care physician with a ganglion cyst and was sent to an orthopaedist for aspiration. Upon further evaluation with a plain radiograph, the dorsal wrist mass was found to be a carpal boss. The patient was treated with rest and a wrist brace, and was informed that a corticosteroid injection or surgical excision would be necessary if conservative treatment failed. The patient was asymptomatic on follow-up and invasive procedures were not necessary. PMID:22707539

  9. [Ganglion cysts of the hand and wrist].

    Science.gov (United States)

    Sarig, Oren; Hass, Avraham; Oron, Amir

    2013-10-01

    Ganglion cysts are considered the most common tumor of the wrist and hand. They are most common between the second and fourth decades of life. The most common anatomical location is the dorsal wrist. This article includes a general review of these cysts including symptoms, pathology and methods of diagnosis, as well as a review of these cysts in specific anatomic locations. The article also includes an updated review of the literature comparing open surgery vs. arthroscopic treatment. The authors believe that arthroscopic surgery of ganglion cysts will gain an important role in the treatment of these cysts. PMID:24450035

  10. Circadian clock, cell cycle and cancer

    Directory of Open Access Journals (Sweden)

    Cansu Özbayer

    2011-12-01

    Full Text Available There are a few rhythms of our daily lives that we are under the influence. One of them is characterized by predictable changes over a 24-hour timescale called circadian clock. This cellular clock is coordinated by the suprachiasmatic nucleus in the anterior hypothalamus. The clock consist of an autoregulatory transcription-translation feedback loop compose of four genes/proteins; BMAL1, Clock, Cyrptochrome, and Period. BMAL 1 and Clock are transcriptional factors and Period and Cyrptochrome are their targets. Period and Cyrptochrome dimerize in the cytoplasm to enter the nucleus where they inhibit Clock/BMAL activity.It has been demonstrate that circadian clock plays an important role cellular proliferation, DNA damage and repair mechanisms, checkpoints, apoptosis and cancer.

  11. Robot-Aided Mapping of Wrist Proprioceptive Acuity across a 3D Workspace.

    Science.gov (United States)

    Marini, Francesca; Squeri, Valentina; Morasso, Pietro; Konczak, Jürgen; Masia, Lorenzo

    2016-01-01

    Proprioceptive signals from peripheral mechanoreceptors form the basis for bodily perception and are known to be essential for motor control. However we still have an incomplete understanding of how proprioception differs between joints, whether it differs among the various degrees-of-freedom (DoFs) within a particular joint, and how such differences affect motor control and learning. We here introduce a robot-aided method to objectively measure proprioceptive function: specifically, we systematically mapped wrist proprioceptive acuity across the three DoFs of the wrist/hand complex with the aim to characterize the wrist position sense. Thirty healthy young adults performed an ipsilateral active joint position matching task with their dominant wrist using a haptic robotic exoskeleton. Our results indicate that the active wrist position sense acuity is anisotropic across the joint, with the abduction/adduction DoF having the highest acuity (the error of acuity for flexion/extension is 4.64 ± 0.24°; abduction/adduction: 3.68 ± 0.32°; supination/pronation: 5.15 ± 0.37°) and they also revealed that proprioceptive acuity decreases for smaller joint displacements. We believe this knowledge is imperative in a clinical scenario when assessing proprioceptive deficits and for understanding how such sensory deficits relate to observable motor impairments. PMID:27536882

  12. Deletion of the secretory vesicle proteins IA-2 and IA-2β disrupts circadian rhythms of cardiovascular and physical activity

    OpenAIRE

    Kim, Soo Mi; Power, Andrea; Brown, Timothy M.; Constance, Cara M.; Coon, Steven L.; Nishimura, Takuya; Hirai, Hiroki; Cai, Tao; Eisner, Christoph; David R Weaver; Piggins, Hugh D.; Klein, David C.; Schnermann, Jürgen; Notkins, Abner L.

    2009-01-01

    Targeted deletion of IA-2 and IA-2β, major autoantigens in type 1 diabetes and transmembrane secretory vesicle proteins, results in impaired secretion of hormones and neurotransmitters. In the present study, we evaluated the effect of these deletions on daily rhythms in blood pressure, heart rate, core body temperature, and spontaneous physical and neuronal activity. We found that deletion of both IA-2 and IA-2β profoundly disrupts the usual diurnal variation of each of these parameters, wher...

  13. Glaucoma alters the circadian timing system.

    Science.gov (United States)

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A; Denis, Philippe; Cooper, Howard M

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN). In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (approximately 50-70%) of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD) cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system. PMID:19079596

  14. Glaucoma Alters the Circadian Timing System

    Science.gov (United States)

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Denis, Philippe; Cooper, Howard M.

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN). In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (∼50–70%) of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD) cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system. PMID:19079596

  15. Endocrine Effects of Circadian Disruption.

    Science.gov (United States)

    Bedrosian, Tracy A; Fonken, Laura K; Nelson, Randy J

    2016-01-01

    Disruption of circadian rhythms, provoked by artificial lighting at night, inconsistent sleep-wake schedules, and transmeridian air travel, is increasingly prevalent in modern society. Desynchrony of biological rhythms from environmental light cycles has dramatic consequences for human health. In particular, disrupting homeostatic oscillations in endocrine tissues and the hormones that these tissues regulate can have cascading effects on physiology and behavior. Accumulating evidence suggests that chronic disruption of circadian organization of endocrine function may lead to metabolic, reproductive, sleep, and mood disorders. This review discusses circadian control of endocrine systems and the consequences of distorting rhythmicity of these systems. PMID:26208951

  16. Dissociation of ultradian and circadian phenotypes in female and male Siberian hamsters.

    Science.gov (United States)

    Prendergast, Brian J; Cisse, Yasmine M; Cable, Erin J; Zucker, Irving

    2012-08-01

    Three experiments addressed whether pronounced alterations in the circadian system yielded concomitant changes in ultradian timing. Female Siberian hamsters were housed in a 16L:8D photoperiod after being subjected to a disruptive phase-shifting protocol that produced 3 distinct permanent circadian phenotypes: some hamsters entrained their circadian rhythms (CRs) with predominantly nocturnal locomotor activity (ENTR), others displayed free-running CRs (FR), and a third cohort was circadian arrhythmic (ARR). The period of the ultradian locomotor rhythm (UR) did not differ among the 3 circadian phenotypes; neuroendocrine generation of URs remains viable in the absence of coherent circadian organization and appears to be mediated by substrates functionally and anatomically distinct from those that generate CRs. Pronounced light-dark differences in several UR characteristics in ENTR hamsters were completely absent in circadian arrhythmic hamsters. The disruptive phase-shifting protocol may compromise direct visual input to ultradian oscillators but more likely indirectly affects URs by interrupting visual afference to the circadian system. Additional experiments documented that deuterium oxide and constant light, each of which substantially lengthened the period of free-running CRs, failed to change the period of concurrently monitored URs. The resistance of URs to deuteration contrasts with the slowing of virtually all other biological timing processes, including CRs. Considered together, the present results point to the existence of separable control mechanisms for generation of circadian and ultradian rhythms. PMID:22855573

  17. Diminished vagal activity and blunted circadian heart rate dynamics in posttraumatic stress disorder assessed through 24-h linear and unifractal analysis

    OpenAIRE

    Agorastos Agorastos; Oliver Stiedl; Boel, Judith A.; Heppner, Pia S; Torben Hager; Tobias Moeller-Bertram; Uzair Haji; Arame Motazedi; Baker, Dewleen G

    2012-01-01

    Background : Affected autonomic heart regulation is implicated in the pathophysiology of cardiovascular diseases and is also associated with posttraumatic stress disorder (PTSD). However, although sympathetic hyperactivation has been repeatedly shown in PTSD, research has neglected the parasympathetic branch. The objective of this study is the long-term assessment of heart rate (HR) dynamics and its circadian changes as an index of autonomic imbalance in PTSD. Since tonic parasympathetic acti...

  18. Evaluation of wrist arthroscopy outcomes in patients with chronic wrist pain

    OpenAIRE

    Reza Shahryar Kamrani; Mohammad Hossein Nabian; Leila Oryadi Zanjani

    2015-01-01

    Background: Wrist arthroscopy is an evolving diagnostic and therapeutic modality which is progressively used by Iranian surgeons. Little data is published about the procedure’s indications, outcomes, complications and prognostic factors. In following study we evaluate the outcome and complications of diagnostic and therapeutic arthroscopy in our patients. Methods: In a prospective study from September 2009 to March 2013, 100 patients entered in the study. All the patients had chronic wrist...

  19. Positioning of the wrist for scaphoid radiography

    Energy Technology Data Exchange (ETDEWEB)

    Toth, Ferenc [Department of Traumatology and Hand Surgery, Medical School of Pecs University, PF.: 99, Akac utca 1, H-7601 Pecs (Hungary)], E-mail: tothf2@yahoo.com; Sebestyen, Andor [Baranya County Health Insurance Fund, Nagy Lajos kiraly utja 3, 7623 Pecs (Hungary); Balint, Lehel [Department of Orthopaedic Surgery, Medical School of Pecs University, Ifjusag u. 13, 7643 Pecs (Hungary); Mester, Sandor [Szent Gyorgy County Hospital, Seregelyesi u. 3, 8000 Szekesfehervar (Hungary); Szabo, Gyorgy [Department of Orthopaedic Surgery, Medical School of Pecs University, Ifjusag u. 13, 7643 Pecs (Hungary); Nyarady, Jozsef [Department of Traumatology and Hand Surgery, Medical School of Pecs University, PF.: 99, Akac utca 1, H-7601 Pecs (Hungary); Weninger, Csaba [Department of Radiology, Medical School of Pecs University, Ifjusag u. 13, 7643 Pecs (Hungary); Angyal, Miklos [Department of Forensic Medicine, Medical School of Pecs University, Ifjusag u. 13, 7643 Pecs (Hungary); Lovasz, Gyorgy [Department of Orthopaedic Surgery, Medical School of Pecs University, Ifjusag u. 13, 7643 Pecs (Hungary)

    2007-10-15

    Purpose: The purpose of this cadaver study was to determine the ideal position of the wrist for scaphoid radiography. Materials and methods: Four cadaver wrists were rotated around their longitudinal axis in 15 deg. increments and exposures were taken. Seven postero-anterior images were taken as well. Thus, 18 images of each wrist were available for assessment. Views were determined in which the main anatomic regions of the scaphoid were visualized undistorted. The size and localization of the overlap of other carpal bones were also evaluated. Finally, views with the best visualization of anatomic landmarks were selected. The results of these three investigations were compared to literature data. Results: We consider the following four images the most valuable in the diagnostic imaging of scaphoid bone: (1) Postero-anterior view in ulnar deviation of wrist and fist position of the hand; (2) oblique view in 60 deg. of pronation; (3) oblique view in 60 deg. of supination; (4) lateral view. Conclusion: We concluded that our four views are sufficient for proper radiographic evaluation of the scaphoid.

  20. Periprosthetic osteolysis after total wrist arthroplasty

    DEFF Research Database (Denmark)

    Boeckstyns, Michel E H; Herzberg, Guillaume

    2014-01-01

    Background and Literature Review Periprosthetic osteolysis (PPO) after second- or third-generation total wrist arthroplasty (TWA), with or without evident loosening of the implant components, has previously been reported in the literature, but rarely in a systematic way. Purpose The purpose of th...

  1. Cardiovascular tissues contain independent circadian clocks

    Science.gov (United States)

    Davidson, A. J.; London, B.; Block, G. D.; Menaker, M.

    2005-01-01

    Acute cardiovascular events exhibit a circadian rhythm in the frequency of occurrence. The mechanisms underlying these phenomena are not yet fully understood, but they may be due to rhythmicity inherent in the cardiovascular system. We have begun to characterize rhythmicity of the clock gene mPer1 in the rat cardiovascular system. Luciferase activity driven by the mPer1 gene promoter is rhythmic in vitro in heart tissue explants and a wide variety of veins and arteries cultured from the transgenic Per1-luc rat. The tissues showed between 3 and 12 circadian cycles of gene expression in vitro before damping. Whereas peak per1-driven bioluminescence consistently occurred during the late night in the heart and all arteries sampled, the phases of the rhythms in veins varied significantly by anatomical location. Varying the time of the culture procedure relative to the donor animal's light:dark cycle revealed that, unlike some other rat tissues such as liver, the phases of in vitro rhythms of arteries, veins, and heart explants were affected by culture time. However, phase relationships among tissues were consistent across culture times; this suggests diversity in circadian regulation among components of the cardiovascular system.

  2. Circadian Control of Global Transcription

    Science.gov (United States)

    Li, Shujing; Zhang, Luoying

    2015-01-01

    Circadian rhythms exist in most if not all organisms on the Earth and manifest in various aspects of physiology and behavior. These rhythmic processes are believed to be driven by endogenous molecular clocks that regulate rhythmic expression of clock-controlled genes (CCGs). CCGs consist of a significant portion of the genome and are involved in diverse biological pathways. The transcription of CCGs is tuned by rhythmic actions of transcription factors and circadian alterations in chromatin. Here, we review the circadian control of CCG transcription in five model organisms that are widely used, including cyanobacterium, fungus, plant, fruit fly, and mouse. Comparing the similarity and differences in the five organisms could help us better understand the function of the circadian clock, as well as its output mechanisms adapted to meet the demands of diverse environmental conditions. PMID:26682214

  3. Circadian Control of Global Transcription

    Directory of Open Access Journals (Sweden)

    Shujing Li

    2015-01-01

    Full Text Available Circadian rhythms exist in most if not all organisms on the Earth and manifest in various aspects of physiology and behavior. These rhythmic processes are believed to be driven by endogenous molecular clocks that regulate rhythmic expression of clock-controlled genes (CCGs. CCGs consist of a significant portion of the genome and are involved in diverse biological pathways. The transcription of CCGs is tuned by rhythmic actions of transcription factors and circadian alterations in chromatin. Here, we review the circadian control of CCG transcription in five model organisms that are widely used, including cyanobacterium, fungus, plant, fruit fly, and mouse. Comparing the similarity and differences in the five organisms could help us better understand the function of the circadian clock, as well as its output mechanisms adapted to meet the demands of diverse environmental conditions.

  4. Endocrine regulation of circadian physiology.

    Science.gov (United States)

    Tsang, Anthony H; Astiz, Mariana; Friedrichs, Maureen; Oster, Henrik

    2016-07-01

    Endogenous circadian clocks regulate 24-h rhythms of behavior and physiology to align with external time. The endocrine system serves as a major clock output to regulate various biological processes. Recent findings suggest that some of the rhythmic hormones can also provide feedback to the circadian system at various levels, thus contributing to maintaining the robustness of endogenous rhythmicity. This delicate balance of clock-hormone interaction is vulnerable to modern lifestyle factors such as shiftwork or high-calorie diets, altering physiological set points. In this review, we summarize the current knowledge on the communication between the circadian timing and endocrine systems, with a focus on adrenal glucocorticoids and metabolic peptide hormones. We explore the potential role of hormones as systemic feedback signals to adjust clock function and their relevance for the maintenance of physiological and metabolic circadian homeostasis. PMID:27106109

  5. The circadian clock goes genomic

    OpenAIRE

    Staiger, D; Shin, J; Johansson, M; Davis, S

    2013-01-01

    Large-scale biology among plant species, as well as comparative genomics of circadian clock architecture and clock-regulated output processes, have greatly advanced our understanding of the endogenous timing system in plants.

  6. Circadian Rhythm Management System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The value of measuring sleep-wake cycles is significantly enhanced by measuring other physiological signals that depend on circadian rhythms (such as heart rate and...

  7. Distinct thalamo-cortical controls for shoulder, elbow, and wrist during locomotion

    Directory of Open Access Journals (Sweden)

    Irina N. Beloozerova

    2013-05-01

    Full Text Available Recent data from this laboratory on differential controls for the shoulder, elbow, and wrist exerted by the thalamo-cortical network during locomotion is presented, based on experiments involving chronically instrumented cats walking on a flat surface and along a horizontal ladder. The activity of the following three groups of neurons is characterized: 1 neurons of the motor cortex that project to the pyramidal tract (PTNs, 2 neurons of the ventrolateral thalamus (VL, many identified as projecting to the motor cortex (thalamo-cortical neurons, TCs, and 3 neurons of the reticular nucleus of thalamus (RE, which inhibit TCs. Neurons were grouped according to their receptive field into shoulder-, elbow-, and wrist/paw-related categories. During simple locomotion, shoulder-related PTNs were most active in the late stance and early swing, and on the ladder, often increased activity and step-related modulation while reducing discharge duration. Elbow-related PTNs were most active during late swing/early stance and typically remained similar on the ladder. Wrist-related PTNs were most active during swing, and on the ladder often decreased activity and increased modulation while reducing discharge duration.In the VL, shoulder-related neurons were more active during transition from swing to stance. Elbow-related cells tended to be more active during transition from stance to swing and on the ladder often decreased their activity and increased modulation. Wrist-related neurons were more active throughout the stance phase. In the RE, shoulder-related cells had low discharge rates and depths of modulation and long periods of activity distributed evenly across the cycle. In contrast, wrist/paw-related cells discharged synchronously during end of stance and swing with short periods of high activity, high modulation, and frequent sleep-type bursting. We conclude that thalamo-cortical network processes information related to different segments of the forelimb

  8. Postoperative circadian disturbances

    DEFF Research Database (Denmark)

    Gögenur, Ismail

    2010-01-01

    reduced the first night after minimally invasive surgery. The core body temperature rhythm was disturbed after both major and minor surgery. There was a change in the sleep wake cycle with a significantly increased duration of REM-sleep in the day and evening time after major surgery compared with...... after major surgery was increased on the fourth day after surgery and the total excretion of AMT6s in urine was correlated to sleep efficiency and wake time after sleep onset, but was not correlated to the occurrence of postoperative cognitive dysfunction. We could only prove an effect of melatonin...... substitution in patients with lower than median pain levels for a three days period after laparoscopic cholecystectomy. In the series of studies included in this thesis we have systematically shown that circadian disturbances are found in the secretion of hormones, the sleep-wake cycle, core body temperature...

  9. Application of the Blobo bluetooth ball in wrist rehabilitation training.

    Science.gov (United States)

    Hsieh, Wei-Min; Hwang, Yuh-Shyan; Chen, Shih-Ching; Tan, Sun-Yen; Chen, Chih-Chen; Chen, Yu-Luen

    2016-01-01

    [Purpose] The introduction of emerging technologies such as the wireless Blobo bluetooth ball with multimedia features can enhance wrist physical therapy training, making it more fun and enhancing its effects. [Methods] Wrist injuries caused by fatigue at work, improper exercise, and other conditions are very common. Therefore, the reconstruction of wrist joint function is an important issue. The efficacy of a newly developed integrated wrist joint rehabilitation game using a Blobo bluetooth ball with C# software installed was tested in wrist rehabilitation (Flexion, Extension, Ulnar Deviation, Radial Deviation). [Results] Eight subjects with normal wrist function participated in a test of the system's stability and repeatability. After performing the Blobo bluetooth ball wrist physical therapy training, eight patients with wrist dysfunction experienced approximately 10° improvements in range of motion (ROM) of flexion extension, and ulnar deviation and about 6° ROM improvement in radial deviation. The subjects showed progress in important indicators of wrist function. [Conclusion] This study used the Blobo bluetooth ball in wrist physical therapy training and the preliminary results were encouraging. In the future, more diverse wrist or limb rehabilitation games should be developed to meet the needs of physical therapy training. PMID:26957723

  10. The circadian clock in mammals

    OpenAIRE

    Zordan, Mauro; Kyriacou, Charalambos P

    2000-01-01

    The basic physiological and anatomical basis for circadian rhythms in mammalian behaviour and physiology is introduced. The pathways involved in photic entrainment of the circadian clock are discussed in relation of new findings that identify the molecules that are involved in signalling between the environment and the clock. The molecular basis of endogenous cycles is described in the mouse, and compared to the mechanism that is present in the fly. Finally we speculate on the relationship be...

  11. The circadian clock in mammals

    OpenAIRE

    Zordan, M. A.; Kyriacou, C P

    2005-01-01

    The basic physiological and anatomical basis for circadian rhythms in mammalian behaviour and physiology is introduced. The pathways involved in photic entrainment of the circadian clock are discussed in relation of new findings that identify the molecules that are involved in signalling between the environment and the clock. The molecular basis of endogenous cycles is described in the mouse, and compared to the mechanism that is present in the fly. Finally we speculate on the relationship be...

  12. Circadian Pacemaker – Temperature Compensation

    OpenAIRE

    Gerkema, Menno P.; Binder, Marc D.; Hirokawa, Nobutaka; Windhorst, Uwe

    2009-01-01

    One of the defining characteristics of circadian pacemakers and indicates the independence of the speed of circadian clock processes of environmental temperature. Mechanisms involved, so far not elucidated in full detail, entail at least two processes that are similarly affected by temperature changes, but with an opposing and counterbalancing effect on the periodicity of the clock system. As a result of temperature compensation, the increase in reaction velocity for every 10° rise in tempera...

  13. Die circadiane Uhr im Immunsystem

    OpenAIRE

    Keller, Maren

    2010-01-01

    Daily rhythms of a variety of immunological phenomena and functions are well known, but so far they have largely been neglected. Examples of daily rhythms in the immune system are: circadian differences in susceptibility to bacterial infection and daily variations in the symptoms of diseases such as rheumatoid arthritis or asthma. Therefore, it is very important for clinical diagnosis and pharmacological therapies to elucidate the connections between the circadian clock and the immune system....

  14. Wpływ prądów TENS średniej częstotliwości na czynność bioelektyczną mięśni prostowników nadgarstka = The influence of mid-frequency TENS currents on bioelectrical activity of the wrist extensor muscles.

    OpenAIRE

    Srokowski, Grzegorz; Piekorz, Zuzanna; Siedlaczek, Marcin; Kowalik, Tomasz; Paduch, Daria; Srokowska, Anna; Zukow, Walery

    2015-01-01

    Srokowski Grzegorz, Piekorz Zuzanna, Siedlaczek Marcin, Kowalik Tomasz, Paduch Daria, Srokowska Anna, Zukow Walery. Wpływ prądów TENS średniej częstotliwości na czynność bioelektyczną mięśni prostowników nadgarstka = The influence of mid-frequency TENS currents on bioelectrical activity of the wrist extensor muscles. Journal of Education, Health and Sport. 2015;5(9):768-791. ISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.44371 http://ojs.ukw.edu.pl/index.php/johs/artic...

  15. Natural selection against a circadian clock gene mutation in mice.

    Science.gov (United States)

    Spoelstra, Kamiel; Wikelski, Martin; Daan, Serge; Loudon, Andrew S I; Hau, Michaela

    2016-01-19

    Circadian rhythms with an endogenous period close to or equal to the natural light-dark cycle are considered evolutionarily adaptive ("circadian resonance hypothesis"). Despite remarkable insight into the molecular mechanisms driving circadian cycles, this hypothesis has not been tested under natural conditions for any eukaryotic organism. We tested this hypothesis in mice bearing a short-period mutation in the enzyme casein kinase 1ε (tau mutation), which accelerates free-running circadian cycles. We compared daily activity (feeding) rhythms, survivorship, and reproduction in six replicate populations in outdoor experimental enclosures, established with wild-type, heterozygous, and homozygous mice in a Mendelian ratio. In the release cohort, survival was reduced in the homozygote mutant mice, revealing strong selection against short-period genotypes. Over the course of 14 mo, the relative frequency of the tau allele dropped from initial parity to 20%. Adult survival and recruitment of juveniles into the population contributed approximately equally to the selection for wild-type alleles. The expression of activity during daytime varied throughout the experiment and was significantly increased by the tau mutation. The strong selection against the short-period tau allele observed here contrasts with earlier studies showing absence of selection against a Period 2 (Per2) mutation, which disrupts internal clock function, but does not change period length. These findings are consistent with, and predicted by the theory that resonance of the circadian system plays an important role in individual fitness. PMID:26715747

  16. Effects of afternoon "siesta" naps on sleep, alertness, performance, and circadian rhythms in the elderly

    Science.gov (United States)

    Monk, T. H.; Buysse, D. J.; Carrier, J.; Billy, B. D.; Rose, L. R.

    2001-01-01

    STUDY OBJECTIVES: To determine the effects of a 90-minute afternoon nap regimen on nocturnal sleep, circadian rhythms, and evening alertness and performance levels in the healthy elderly. DESIGN AND SETTING: Nine healthy elderly subjects (4m, 5f, age range 74y-87y) each experienced both nap and no-nap conditions in two studies each lasting 17 days (14 at home, 3 in the laboratory). In the nap condition a 90-minute nap was enforced between 13:30 and 15:00 every day, in the no-nap condition daytime napping was prohibited, and activity encouraged in the 13:30-15:00 interval. The order of the two conditions was counterbalanced. PARTICIPANTS: N/A INTERVENTIONS: N/A MEASUREMENTS: Diary measures, pencil and paper alertness tests, and wrist actigraphy were used at home. In the 72 hour laboratory studies, these measures were augmented by polysomnographic sleep recording, continuous rectal temperature measurement, a daily evening single trial of a Multiple Sleep Latency Test (MSLT), and computerized tests of mood, activation and performance efficiency. RESULTS: By the second week in the "at home" study, an average of 58 minutes of sleep was reported per siesta nap; in the laboratory, polysomnography confirmed an average of 57 minutes of sleep per nap. When nap and no-nap conditions were compared, mixed effects on nocturnal sleep were observed. Diary measures indicated no significant difference in nocturnal sleep duration, but a significant increase (of 38 mins.) in 24-hour Total Sleep Time (TST) when nocturnal sleeps and naps were added together (psleep efficiency in the nap condition (pSleep Time (TST) by 48 mins. in the nap condition (peffects on Wake After Sleep Onset (WASO), delta sleep measures, or percent stages 1 & 2. Unlike the diary study, the laboratory study yielded no overall increase in 24-hour TST consequent upon the siesta nap regimen. The only measure of evening alertness or performance to show an improvement was sleep latency in a single-trial evening MSLT

  17. Gravitational biology and the mammalian circadian timing system

    Science.gov (United States)

    Fuller, Charles A.; Murakami, Dean M.; Sulzman, Frank M.

    1989-01-01

    Using published reports, this paper compares and contrasts results on the effects of altered gravitational fields on the regulation in mammals of several physiological and behavioral variables with the circadian regulation of the same variables. The variables considered include the temperature regulation, heart rate, activity, food intake, and calcium balance. It is shown that, in rats, the homeostatic regulation of the body temperature, heart rate, and activity becomes depressed following exposure to a 2 G hyperdynamic field, and recovers within 6 days of 1 G condition. In addition, the circadian rhythms of these variables exhibit a depression of the rhythm amplitude; a recovery of this condition requires a minimum of 7 days.

  18. Effects of 9-hour time zone changes on fatigue and circadian rhythms of sleep/wake and core temperature

    Science.gov (United States)

    Gander, P. H.; Myhre, G.; Graeber, R. C.; Andersen, H. T.; Lauber, J. K.

    1985-01-01

    Physiological and psychological disruptions caused by transmeridian flights may affect the ability of flight crews to meet operational demands. To study these effects, 9 Royal Norwegian Airforces P3-Orion crewmembers flew from Norway to California (-9 hr), and back (+9 hr). Rectal temperature, heart rate and wrist activity were recorded every 2 min, fatigue and mood were rated every 2 hr during the waking day, and logs were kept of sleep times and ratings. Subjects also completed 4 personality inventories. The time-zone shifts produced negative changes in mood which persisted longer after westward flights. Sleep quality (subjective and objective) and duration were slightly disrupted (more after eastward flights). The circadian rhythms of sleep/wake and temperature both completed the 9-hr delay by day 5 in California, although temperature adjusted more slowly. The size of the delay shift was significantly correlated with scores on extraversion and achievement need personality scales. Response to the 9-hr advance were more variable. One subject exhibited a 15-hr delay in his temperature rhythm, and an atypical sleep/nap pattern. On average, the sleep/wake cycle (but not the temperature rhythm), completed the 9-hr advance by the end of the study. Both rhythms adapted more slowly after the eastward flight.

  19. Plasticity of the intrinsic period of the human circadian timing system.

    Directory of Open Access Journals (Sweden)

    Frank A J L Scheer

    Full Text Available Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol, which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here whether such prior entrainment to non-24-h light-dark cycles would lead to subsequent modification of the intrinsic period of the human circadian timing system. Here we show that exposure to moderately bright light ( approximately 450 lux; approximately 1.2 W/m(2 for the second or first half of the scheduled wake episode is effective for entraining individuals to the 24.65-h Martian sol and a 23.5-h day length, respectively. Estimations of the circadian periods of plasma melatonin, plasma cortisol, and core body temperature rhythms collected under forced desynchrony protocols revealed that the intrinsic circadian period of the human circadian pacemaker was significantly longer following entrainment to the Martian sol as compared to following entrainment to the 23.5-h day. The latter finding of after-effects of entrainment reveals for the first time plasticity of the period of the human circadian timing system. Both findings have important implications for the treatment of circadian rhythm sleep disorders and human space exploration.

  20. Amsterdam wrist rules: A clinical decision aid

    Directory of Open Access Journals (Sweden)

    Bentohami Abdelali

    2011-10-01

    Full Text Available Abstract Background Acute trauma of the wrist is one of the most frequent reasons for visiting the Emergency Department. These patients are routinely referred for radiological examination. Most X-rays however, do not reveal any fractures. A clinical decision rule determining the need for X-rays in patients with acute wrist trauma may help to percolate and select patients with fractures. Methods/Design This study will be a multi-center observational diagnostic study in which the data will be collected cross-sectionally. The study population will consist of all consecutive adult patients (≥18 years presenting with acute wrist trauma at the Emergency Department in the participating hospitals. This research comprises two components: one study will be conducted to determine which clinical parameters are predictive for the presence of a distal radius fracture in adult patients presenting to the Emergency Department following acute wrist trauma. These clinical parameters are defined by trauma-mechanism, physical examination, and functional testing. This data will be collected in two of the three participating hospitals and will be assessed by using logistic regression modelling to estimate the regression coefficients after which a reduced model will be created by means of a log likelihood ratio test. The accuracy of the model will be estimated by a goodness of fit test and an ROC curve. The final model will be validated internally through bootstrapping and by shrinking it, an adjusted model will be generated. In the second component of this study, the developed prediction model will be validated in a new dataset consisting of a population of patients from the third hospital. If necessary, the model will be calibrated using the data from the validation study. Discussion Wrist trauma is frequently encountered at the Emergency Department. However, to this date, no decision rule regarding this type of trauma has been created. Ideally, radiographs are

  1. Drosophila spaghetti and doubletime link the circadian clock and light to caspases, apoptosis and tauopathy.

    Directory of Open Access Journals (Sweden)

    John C Means

    2015-05-01

    Full Text Available While circadian dysfunction and neurodegeneration are correlated, the mechanism for this is not understood. It is not known if age-dependent circadian dysfunction leads to neurodegeneration or vice-versa, and the proteins that mediate the effect remain unidentified. Here, we show that the knock-down of a regulator (spag of the circadian kinase Dbt in circadian cells lowers Dbt levels abnormally, lengthens circadian rhythms and causes expression of activated initiator caspase (Dronc in the optic lobes during the middle of the day or after light pulses at night. Likewise, reduced Dbt activity lengthens circadian period and causes expression of activated Dronc, and a loss-of-function mutation in Clk also leads to expression of activated Dronc in a light-dependent manner. Genetic epistasis experiments place Dbt downstream of Spag in the pathway, and Spag-dependent reductions of Dbt are shown to require the proteasome. Importantly, activated Dronc expression due to reduced Spag or Dbt activity occurs in cells that do not express the spag RNAi or dominant negative Dbt and requires PDF neuropeptide signaling from the same neurons that support behavioral rhythms. Furthermore, reduction of Dbt or Spag activity leads to Dronc-dependent Drosophila Tau cleavage and enhanced neurodegeneration produced by human Tau in a fly eye model for tauopathy. Aging flies with lowered Dbt or Spag function show markers of cell death as well as behavioral deficits and shortened lifespans, and even old wild type flies exhibit Dbt modification and activated caspase at particular times of day. These results suggest that Dbt suppresses expression of activated Dronc to prevent Tau cleavage, and that the circadian clock defects confer sensitivity to expression of activated Dronc in response to prolonged light. They establish a link between the circadian clock factors, light, cell death pathways and Tau toxicity, potentially via dysregulation of circadian neuronal remodeling in

  2. Disrupting circadian homeostasis of sympathetic signaling promotes tumor development in mice.

    Directory of Open Access Journals (Sweden)

    Susie Lee

    Full Text Available BACKGROUND: Cell proliferation in all rapidly renewing mammalian tissues follows a circadian rhythm that is often disrupted in advanced-stage tumors. Epidemiologic studies have revealed a clear link between disruption of circadian rhythms and cancer development in humans. Mice lacking the circadian genes Period1 and 2 (Per or Cryptochrome1 and 2 (Cry are deficient in cell cycle regulation and Per2 mutant mice are cancer-prone. However, it remains unclear how circadian rhythm in cell proliferation is generated in vivo and why disruption of circadian rhythm may lead to tumorigenesis. METHODOLOGY/PRINCIPAL FINDINGS: Mice lacking Per1 and 2, Cry1 and 2, or one copy of Bmal1, all show increased spontaneous and radiation-induced tumor development. The neoplastic growth of Per-mutant somatic cells is not controlled cell-autonomously but is dependent upon extracellular mitogenic signals. Among the circadian output pathways, the rhythmic sympathetic signaling plays a key role in the central-peripheral timing mechanism that simultaneously activates the cell cycle clock via AP1-controlled Myc induction and p53 via peripheral clock-controlled ATM activation. Jet-lag promptly desynchronizes the central clock-SNS-peripheral clock axis, abolishes the peripheral clock-dependent ATM activation, and activates myc oncogenic potential, leading to tumor development in the same organ systems in wild-type and circadian gene-mutant mice. CONCLUSIONS/SIGNIFICANCE: Tumor suppression in vivo is a clock-controlled physiological function. The central circadian clock paces extracellular mitogenic signals that drive peripheral clock-controlled expression of key cell cycle and tumor suppressor genes to generate a circadian rhythm in cell proliferation. Frequent disruption of circadian rhythm is an important tumor promoting factor.

  3. Dysregulation of circadian rhythms following prolactin-secreting pituitary microadenoma.

    Science.gov (United States)

    Borodkin, Katy; Ayalon, Liat; Kanety, Hanna; Dagan, Yaron

    2005-01-01

    A patient who developed an irregular sleep-wake pattern following prolactin-secreting pituitary microadenoma is described. The patient reported difficulties in sleep onset and awakening at the desired time, which caused major dysfunction in his daily life activities. Despite these difficulties, the sleep-related complaints of the patient remained unrecognized for as long as three yrs. Statistical analyses of the patient's rest-activity patterns revealed that the disruption of the sleep-wake circadian rhythm originated from a disharmony between ultradian (semicircadian) and circadian components. The circadian component displayed shorter than 24 h periodicity most of the time, but the semicircadian component fluctuated between longer and shorter than 12 h periods. Additionally, desynchrony in terms of period length was found in the tentative analyses of the rest-activity pattern, salivary melatonin, and oral temperature. While the salivary melatonin time series data could be characterized by a best-fit cosine curve of 24 h, the time series data of oral temperature was more compatible with 28 h best-fit curve. The rest-activity cycle during the simultaneous measurements, however, was best approximated by a best-fit curve of 21 h. The dysregulation of circadian rhythms occurred concomitantly, but not beforehand, with the onset of pituitary disease, thus suggesting an association between the two phenomena. This association may have interesting implications to the modeling of the circadian time-keeping system. This case also highlights the need to raise the awareness to circadian rhythm sleep disorders and to consider disruptions of sleep-wake cycle in patients with pituitary adenoma. PMID:15865328

  4. Efeito do uso de órtese de punho na ativação da musculatura flexora e extensora do punho Effect of the use of wrist orthosis on forearm muscle activation

    Directory of Open Access Journals (Sweden)

    Adriana Maria Valladão Novais Van Petten

    2010-01-01

    Full Text Available OBJETIVO: Analisar o efeito do uso de órtese de imobilização do punho, confeccionada com diferentes materiais, na ativação da musculatura flexora e extensora do antebraço durante a realização de tarefas específicas. MÉTODOS: Vinte e seis adultos, com média de idade de 26,2 anos, foram submetidos aos Testes Funcional da Mão de Jebsen-Taylor e de Força de Preensão (dinamômetro Jamar® em três condições: com a mão livre, com o uso de órtese de compósito e com a órtese de termomoldável. Os testes foram realizados apenas com a mão dominante. Durante a realização dos testes, eletrodos de superfície foram afixados nos grupos musculares flexores e extensores do antebraço para registro da atividade elétrica muscular. Os resultados obtidos nas três condições foram comparados e analisados utilizando o teste estatístico de Wilcoxon. RESULTADOS: Foram encontradas diferenças significativas quando comparadas a ativação muscular na condição livre e com o uso de qualquer das órteses. Não foram encontradas diferenças significativas quando comparada a ativação muscular com o uso dos dois tipos de órtese. Observou-se redução da ativação dos músculos extensores do antebraço durante a realização de todas as tarefas e aumento da ativação dos músculos flexores com o uso das órteses. CONCLUSÃO: Esse é um resultado importante para a definição da indicação, ou não, do uso de órteses no processo de reabilitação de várias desordens - entre outras, a tendinite de flexores e extensores do punho e dos dedos -, bem como para a previsão do tempo de uso desses dispositivos.OBJECTIVE: to investigate the effect of wrist immobilization orthoses, made from different materials, on activation of the flexor and extensor musculature of the forearm while performing specific tasks. METHODS: Twenty-six adults, with an average age of 26.2 years, performed the Jebsen-Taylor functional hand test and the Grip Strength test

  5. Results of wrist extension reconstruction in C5-8 brachial plexus palsy by transferring the pronator quadratus motor branch to the extensor carpi radialis brevis muscle.

    Science.gov (United States)

    Bertelli, Jayme Augusto; Ghizoni, Marcos Flávio; Tacca, Cristiano Paulo

    2016-05-01

    OBJECT The objective of this study was to report the results of pronator quadratus (PQ) motor branch transfers to the extensor carpi radialis brevis (ECRB) motor branch to reconstruct wrist extension in C5-8 root lesions of the brachial plexus. METHODS Twenty-eight patients, averaging 24 years of age, with C5-8 root injuries underwent operations an average of 7 months after their accident. In 19 patients, wrist extension was impossible at baseline, whereas in 9 patients wrist extension was managed by activating thumb and wrist extensors. When these 9 patients grasped an object, their wrist dropped and grasp strength was lost. Wrist extension was reconstructed by transferring the PQ motor to the ECRB motor branch. After surgery, patients were followed for at least 12 months, with final follow-up an average of 22 months after surgery. RESULTS Successful reinnervation of the ECRB was demonstrated in 27 of the 28 patients. In 25 of the patients, wrist extension scored M4, and in 2 it scored M3. CONCLUSIONS In C5-8 root injuries, wrist extension can be predictably reconstructed by transferring the PQ motor branch to reinnervate the ECRB. PMID:26430841

  6. Sleep disturbances and circadian CLOCK genes in borderline personality disorder.

    Science.gov (United States)

    Fleischer, Monika; Schäfer, Michael; Coogan, Andrew; Häßler, Frank; Thome, Johannes

    2012-10-01

    Borderline personality disorder (BPD) is characterised by a deep-reaching pattern of affective instability, incoherent identity, self-injury, suicide attempts, and disturbed interpersonal relations and lifestyle. The daily activities of BPD patients are often chaotic and disorganized, with patients often staying up late while sleeping during the day. These behavioural patterns suggest that altered circadian rhythms may be associated with BPD. Furthermore, BPD patients frequently report suffering from sleep disturbances. In this review, we overview the evidence that circadian rhythms and sleep are disturbed in BPD, and we explore the possibility that personality traits that are pertinent for BPD may be associated with circadian typology, and perhaps to circadian genotypes. With regards to sleep architecture, we review the evidence that BPD patients display altered non-REM and REM sleep. A possible cue to a deeper understanding of this temporal dysregulation might be an analysis of the circadian clock at the molecular and cellular level, as well as behavioural studies using actigraphy and we suggest avenues for further exploration of these factors. PMID:22806005

  7. Temporal Regulation of Cytokines by the Circadian Clock

    Directory of Open Access Journals (Sweden)

    Atsuhito Nakao

    2014-01-01

    Full Text Available Several parameters of the immune system exhibit oscillations with a period of approximately 24 hours that refers to “circadian rhythms.” Such daily variations in host immune system status might evolve to maximize immune reactions at times when encounters with pathogens are most likely to occur. However, the mechanisms behind circadian immunity have not been fully understood. Recent studies reveal that the internal time keeping system “circadian clock” plays a key role in driving the daily rhythms evident in the immune system. Importantly, several studies unveil molecular mechanisms of how certain clock proteins (e.g., BMAL1 and CLOCK temporally regulate expression of cytokines. Since cytokines are crucial mediators for shaping immune responses, this review mainly summarizes the new knowledge that highlights an emerging role of the circadian clock as a novel regulator of cytokines. A greater understanding of circadian regulation of cytokines will be important to exploit new strategies to protect host against infection by efficient cytokine induction or to treat autoimmunity and allergy by ameliorating excessive activity of cytokines.

  8. Dorsal wrist ganglion: Current review of literature

    OpenAIRE

    Meena, Sanjay; Gupta, Ajay

    2014-01-01

    Ganglion cyst is the most common soft tissue tumour of hand. Sixty to seventy percent of ganglion cysts are found in the dorsal aspect of the wrist. They may affect any age group; however they are more common in the twenties to forties. Its origin and pathogenesis remains enigmatic. Non-surgical treatment is unreliable with a high recurrence rates. Open surgical excision leads to unsightly scar and poor outcome. Arthroscopy excision has shown very promising result with very low recurrence rat...

  9. Effects of the circadian rhythm gene period 1 (per1) on psychosocial stress-induced alcohol drinking

    OpenAIRE

    Soyka, Michael; Henriksson, Richard; Albrecht, Urs; Spanagel, Rainer; Michael N Smolka; Rietschel, Marcella; Bilbao, Ainhoa; Treutlein, Jens; Schumann, Gunter; Ridinger, Monika; Wodarz, Norbert; Blomeyer, Dorothea; Witt, Stephanie,; Lathrop, Mark; Dong, Li

    2011-01-01

    Objective: Circadian and stress-response systems mediate environmental changes that affect alcohol drinking. Psychosocial stress is an environmental risk factor for alcohol abuse. Circadian rhythm gene period 1 (Per1) is targeted by stress hormones and is transcriptionally activated in corticotropin releasing factor-expressing cells. The authors hypothesized that Per1 is involved in integrating stress response and circadian rhythmicity and explored its relevance to alcohol drinking.Method: In...

  10. Time for a Nuclear Meeting: Protein Trafficking and Chromatin Dynamics Intersect in the Plant Circadian System

    Institute of Scientific and Technical Information of China (English)

    Eva Herrero; Seth J. Davis

    2012-01-01

    Circadian clocks mediate adaptation to the 24-h world.In Arabidopsis,most circadian-clock components act in the nucleus as transcriptional regulators and generate rhythmic oscillations of transcript accumulation.In this review,we focus on post-transcriptional events that modulate the activity of circadian-clock components,such as phosphorylation,ubiquitination and proteasome-mediated degradation,changes in cellular localization,and protein-protein interactions.These processes have been found to be essential for circadian function,not only in plants,but also in other circadian systems.Moreover,light and clock signaling networks are highly interconnected.In the nucleus,light and clock components work together to generate transcriptional rhythms,leading to a general control of the timing of plant physiological processes.

  11. Interaction of MAGED1 with nuclear receptors affects circadian clock function

    Science.gov (United States)

    Wang, Xiaohan; Tang, Jing; Xing, Lijuan; Shi, Guangsen; Ruan, Haibin; Gu, Xiwen; Liu, Zhiwei; Wu, Xi; Gao, Xiang; Xu, Ying

    2010-01-01

    The circadian clock has a central role in physiological adaption and anticipation of day/night changes. In a genetic screen for novel regulators of circadian rhythms, we found that mice lacking MAGED1 (Melanoma Antigen Family D1) exhibit a shortened period and altered rest–activity bouts. These circadian phenotypes are proposed to be caused by a direct effect on the core molecular clock network that reduces the robustness of the circadian clock. We provide in vitro and in vivo evidence indicating that MAGED1 binds to RORα to bring about positive and negative effects on core clock genes of Bmal1, Rev-erbα and E4bp4 expression through the Rev-Erbα/ROR responsive elements (RORE). Maged1 is a non-rhythmic gene that, by binding RORα in non-circadian way, enhances rhythmic input and buffers the circadian system from irrelevant, perturbing stimuli or noise. We have thus identified and defined a novel circadian regulator, Maged1, which is indispensable for the robustness of the circadian clock to better serve the organism. PMID:20300063

  12. High-energy injuries of the wrist.

    Science.gov (United States)

    Obert, L; Loisel, F; Jardin, E; Gasse, N; Lepage, D

    2016-02-01

    High-energy injuries to the wrist gather complex fractures of the distal radius, radiocarpal dislocations, perilunate dislocations, and other intracarpal dislocations. Depending on the energy of the injury and the position of the wrist at the time of impact, the patient, often a young male with a high functional demand, presents one of these injuries associating fracture(s) and ligament injury. The trauma is often bilateral, with proximal lesions (elbow) very often associated with contusion or compression of the median nerve. Diagnosis is confirmed by wrist X-rays, which are sufficient to determine treatment for radiocarpal and perilunate dislocations. In cases of distal radius fractures or other intracarpal dislocations, a preoperative CT is necessary. Reduction of the dislocation and relief of neurovascular compression are performed immediately. The final treatment of each lesion (bone fixation, ligament repair) can be undertaken simultaneously or delayed, depending on the patient and the lesions. Cartilage lesions, resulting from the high-energy injury, can be estimated using arthroscopy but cannot be repaired and determine the prognosis. The surgeon's objective is to restore joint congruence, which does not prevent stiffness, the main complication of these rare injuries, which the surgeon must know how to recognize and treat. PMID:26782706

  13. A cable-driven wrist robotic rehabilitator using a novel torque-field controller for human motion training

    Science.gov (United States)

    Chen, Weihai; Cui, Xiang; Zhang, Jianbin; Wang, Jianhua

    2015-06-01

    Rehabilitation technologies have great potentials in assisted motion training for stroke patients. Considering that wrist motion plays an important role in arm dexterous manipulation of activities of daily living, this paper focuses on developing a cable-driven wrist robotic rehabilitator (CDWRR) for motion training or assistance to subjects with motor disabilities. The CDWRR utilizes the wrist skeletal joints and arm segments as the supporting structure and takes advantage of cable-driven parallel design to build the system, which brings the properties of flexibility, low-cost, and low-weight. The controller of the CDWRR is designed typically based on a virtual torque-field, which is to plan "assist-as-needed" torques for the spherical motion of wrist responding to the orientation deviation in wrist motion training. The torque-field controller can be customized to different levels of rehabilitation training requirements by tuning the field parameters. Additionally, a rapidly convergent parameter self-identification algorithm is developed to obtain the uncertain parameters automatically for the floating wearable structure of the CDWRR. Finally, experiments on a healthy subject are carried out to demonstrate the performance of the controller and the feasibility of the CDWRR on wrist motion training or assistance.

  14. Analysis of Circadian Leaf Movements.

    Science.gov (United States)

    Müller, Niels A; Jiménez-Gómez, José M

    2016-01-01

    The circadian clock is a molecular timekeeper that controls a wide variety of biological processes. In plants, clock outputs range from the molecular level, with rhythmic gene expression and metabolite content, to physiological processes such as stomatal conductance or leaf movements. Any of these outputs can be used as markers to monitor the state of the circadian clock. In the model plant Arabidopsis thaliana, much of the current knowledge about the clock has been gained from time course experiments profiling expression of endogenous genes or reporter constructs regulated by the circadian clock. Since these methods require labor-intensive sample preparation or transformation, monitoring leaf movements is an interesting alternative, especially in non-model species and for natural variation studies. Technological improvements both in digital photography and image analysis allow cheap and easy monitoring of circadian leaf movements. In this chapter we present a protocol that uses an autonomous point and shoot camera and free software to monitor circadian leaf movements in tomato. PMID:26867616

  15. Nutrition and the circadian system.

    Science.gov (United States)

    Potter, Gregory D M; Cade, Janet E; Grant, Peter J; Hardie, Laura J

    2016-08-01

    The human circadian system anticipates and adapts to daily environmental changes to optimise behaviour according to time of day and temporally partitions incompatible physiological processes. At the helm of this system is a master clock in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. The SCN are primarily synchronised to the 24-h day by the light/dark cycle; however, feeding/fasting cycles are the primary time cues for clocks in peripheral tissues. Aligning feeding/fasting cycles with clock-regulated metabolic changes optimises metabolism, and studies of other animals suggest that feeding at inappropriate times disrupts circadian system organisation, and thereby contributes to adverse metabolic consequences and chronic disease development. 'High-fat diets' (HFD) produce particularly deleterious effects on circadian system organisation in rodents by blunting feeding/fasting cycles. Time-of-day-restricted feeding, where food availability is restricted to a period of several hours, offsets many adverse consequences of HFD in these animals; however, further evidence is required to assess whether the same is true in humans. Several nutritional compounds have robust effects on the circadian system. Caffeine, for example, can speed synchronisation to new time zones after jetlag. An appreciation of the circadian system has many implications for nutritional science and may ultimately help reduce the burden of chronic diseases. PMID:27221157

  16. Molecular bases of circadian rhythmicity in renal physiology and pathology.

    Science.gov (United States)

    Bonny, Olivier; Vinciguerra, Manlio; Gumz, Michelle L; Mazzoccoli, Gianluigi

    2013-10-01

    The physiological processes that maintain body homeostasis oscillate during the day. Diurnal changes characterize kidney functions, comprising regulation of hydro-electrolytic and acid-base balance, reabsorption of small solutes and hormone production. Renal physiology is characterized by 24-h periodicity and contributes to circadian variability of blood pressure levels, related as well to nychthemeral changes of sodium sensitivity, physical activity, vascular tone, autonomic function and neurotransmitter release from sympathetic innervations. The circadian rhythmicity of body physiology is driven by central and peripheral biological clockworks and entrained by the geophysical light/dark cycle. Chronodisruption, defined as the mismatch between environmental-social cues and physiological-behavioral patterns, causes internal desynchronization of periodic functions, leading to pathophysiological mechanisms underlying degenerative, immune related, metabolic and neoplastic diseases. In this review we will address the genetic, molecular and anatomical elements that hardwire circadian rhythmicity in renal physiology and subtend disarray of time-dependent changes in renal pathology. PMID:23901050

  17. Effects of Gravity on Insect Circadian Rhythmicity

    Science.gov (United States)

    Hoban-Higgins, Tana M.

    2000-01-01

    to microgravity was, of necessity, relatively short in duration. In early spaceflight experiments an organism's internal rhythms often expressed periods that were different from each other, even in the presence of a 24.0 hour light-dark cycle, suggesting that the organism was experiencing internal desynchronization (17, 18). In (micro)G, the body temperature rhythm was delayed with respect to other body rhythms and to the light-dark cycle in rhesus macaques (19) and man (20, 21). In the absence of a light-dark cycle, the circadian rhythm of spore formation persisted in Neurospora crassa, however, both the variability and average period of the rhythm increased (22). The beetle Trigonoscelis gigas, exhibited changes in period during and following 11-13 days in (micro)G (23, 24). Resynchronization of the urinary calcium rhythm following a 1800 phase shift of the LID cycle was retarded in rats exposed to (micro)G compared to 1G controls (25). With the development of the Russian Mir Space Station, long-term controlled microgravity exposure became possible. We recorded activity rhythms from black-bodied Tenebrionid beetles, Trigonoscelis gigas, in (micro)G (spaceflight). Each insect was housed individually within an activity monitor (26) and data (activity counts) were collected and stored in five-minute bins. Thirty-two individual activity monitors were housed within each of 2 experimental kits. The beetles within each kit were divided into two groups and the lighting was controlled separately for each group.

  18. Sleep, Circadian Rhythms, and Performance During Space Shuttle Missions

    Science.gov (United States)

    Neri, David F.; Czeisler, Charles A.; Dijk, Derk-Jan; Wyatt, James K.; Ronda, Joseph M.; Hughes, Rod J.

    2003-01-01

    Sleep and circadian rhythms may be disturbed during spaceflight, and these disturbances can affect crewmembers' performance during waking hours. The mechanisms underlying sleep and circadian rhythm disturbances in space are not well understood, and effective countermeasures are not yet available. We investigated sleep, circadian rhythms, cognitive performance, and light-dark cycles in five astronauts prior to, during, and after the 16-day STS-90 mission and the IO-day STS-95 mission. The efficacy of low-dose, alternative-night, oral melatonin administration as a countermeasure for sleep disturbances was evaluated. During these missions, scheduled rest activity cycles were 20-35 minutes shorter than 24 hours. Light levels on the middeck and in the Spacelab were very low; whereas on the flight deck (which has several windows), they were highly variable. Circadian rhythm abnormalities were observed. During the second half of the missions, the rhythm of urinary cortisol appeared to be delayed relative to the sleep-wake schedule. Performance during wakefulness was impaired. Astronauts slept only about 6.5 hours per day, and subjective sleep quality was lower in space. No beneficial effects of melatonin (0.3 mg administered prior to sleep episodes on alternate nights) were observed. A surprising finding was a marked increase in rapid eye movement (REM) sleep upon return to Earth. We conclude that these Space Shuttle missions were associated with circadian rhythm disturbances, sleep loss, decrements in neurobehavioral performance, and alterations in REM sleep homeostasis. Shorter than 24-hour rest-activity schedules and exposure to light-dark cycles inadequate for optimal circadian synchronization may have contributed to these disturbances.

  19. Stiffness, not inertial coupling, determines path curvature of wrist motions.

    Science.gov (United States)

    Charles, Steven K; Hogan, Neville

    2012-02-01

    When humans rotate their wrist in flexion-extension, radial-ulnar deviation, and combinations, the resulting paths (like the path of a laser pointer on a screen) exhibit a distinctive pattern of curvature. In this report we show that the passive stiffness of the wrist is sufficient to account for this pattern. Simulating the dynamics of wrist rotations using a demonstrably realistic model under a variety of conditions, we show that wrist stiffness can explain all characteristics of the observed pattern of curvature. We also provide evidence against other possible causes. We further demonstrate that the phenomenon is robust against variations in human wrist parameters (inertia, damping, and stiffness) and choice of model inputs. Our findings explain two previously observed phenomena: why faster wrist rotations exhibit more curvature and why path curvature rotates with pronation-supination of the forearm. Our results imply that, as in reaching, path straightness is a goal in the planning and control of wrist rotations. This requires humans to predict and compensate for wrist dynamics, but, unlike reaching, nonlinear inertial coupling (e.g., Coriolis acceleration) is insignificant. The dominant term to be compensated is wrist stiffness. PMID:22131378

  20. Maximal dynamic grip force and wrist torque: the effects of gender, exertion direction, angular velocity, and wrist angle.

    Science.gov (United States)

    Morse, Jonathan L; Jung, Myung-Chul; Bashford, Gregory R; Hallbeck, M Susan

    2006-11-01

    The objective of this study was to examine the effects of gender, exertion direction, angular velocity and wrist angle on simultaneous grip force and wrist torque under the isokinetic condition. The study used 20 participants (10 males and 10 females) and included 6 angular velocities (15, 30, 45, 60, 75, and 90 degrees /s) and 2 wrist exertion directions (flexion and extension) over the wrist range of motion of 70 degrees flexion to 60 degrees extension in 5 degrees increments. Similar to other studies, males and flexion exertion produced larger forces than females and extension exertion, respectively. However, the largest forces were generated at near extreme flexion of the wrist and the dependent variable of angular velocity was not practically significant. These results can contribute to the evaluation of cumulative trauma syndromes, but there is a need for more research on the dynamic measures of the hand and wrist complex and for standard development for dynamic force measurement. PMID:16442072

  1. Crystal Structure of the Redox-Active Cofactor Dibromothymoquinone Bound to Circadian Clock Protein KaiA and Structural Basis for Dibromothymoquinone's Ability to Prevent Stimulation of KaiC Phosphorylation by KaiA

    Energy Technology Data Exchange (ETDEWEB)

    Pattanayek, Rekha; Sidiqi, Said K.; Egli, Martin [Vanderbilt-MED

    2013-09-19

    KaiA protein that stimulates KaiC phosphorylation in the cyanobacterial circadian clock was recently shown to be destabilized by dibromothymoquinone (DBMIB), thus revealing KaiA as a sensor of the plastoquinone (PQ) redox state and suggesting an indirect control of the clock by light through PQ redox changes. Here we show using X-ray crystallography that several DBMIBs are bound to KaiA dimer. Some binding modes are consistent with oligomerization of N-terminal KaiA pseudoreceiver domains and/or reduced interdomain flexibility. DBMIB bound to the C-terminal KaiA (C-KaiA) domain and limited stimulation of KaiC kinase activity by C-KaiA in the presence of DBMIB demonstrate that the cofactor may weakly inhibit KaiA-KaiC binding.

  2. Sex differences in the circadian regulation of sleep and waking cognition in humans.

    Science.gov (United States)

    Santhi, Nayantara; Lazar, Alpar S; McCabe, Patrick J; Lo, June C; Groeger, John A; Dijk, Derk-Jan

    2016-05-10

    The sleep-wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep-wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging. PMID:27091961

  3. Circadian transcription contributes to core period determination in Drosophila.

    Directory of Open Access Journals (Sweden)

    Sebastian Kadener

    2008-05-01

    Full Text Available The Clock-Cycle (CLK-CYC heterodimer constitutes a key circadian transcription complex in Drosophila. CYC has a DNA-binding domain but lacks an activation domain. Previous experiments also indicate that most of the transcriptional activity of CLK-CYC derives from the glutamine-rich region of its partner CLK. To address the role of transcription in core circadian timekeeping, we have analyzed the effects of a CYC-viral protein 16 (VP16 fusion protein in the Drosophila system. The addition of this potent and well-studied viral transcriptional activator (VP16 to CYC imparts to the CLK-CYC-VP16 complex strongly enhanced transcriptional activity relative to that of CLK-CYC. This increase is manifested in flies expressing CYC-VP16 as well as in S2 cells. These flies also have increased levels of CLK-CYC direct target gene mRNAs as well as a short period, implicating circadian transcription in period determination. A more detailed examination of reporter gene expression in CYC-VP16-expressing flies suggests that the short period is due at least in part to a more rapid transcriptional phase. Importantly, the behavioral effects require a period (per promoter and are therefore unlikely to be merely a consequence of generally higher PER levels. This indicates that the CLK-CYC-VP16 behavioral effects are a consequence of increased per transcription. All of this also suggests that the timing of transcriptional activation and not the activation itself is the key event responsible for the behavioral effects observed in CYC-VP16-expressing flies. The results taken together indicate that circadian transcription contributes to core circadian function in Drosophila.

  4. Dysglycemia induces abnormal circadian blood pressure variability

    Directory of Open Access Journals (Sweden)

    Kumarasamy Sivarajan

    2011-11-01

    Full Text Available Abstract Background Prediabetes (PreDM in asymptomatic adults is associated with abnormal circadian blood pressure variability (abnormal CBPV. Hypothesis Systemic inflammation and glycemia influence circadian blood pressure variability. Methods Dahl salt-sensitive (S rats (n = 19 after weaning were fed either an American (AD or a standard (SD diet. The AD (high-glycemic-index, high-fat simulated customary human diet, provided daily overabundant calories which over time lead to body weight gain. The SD (low-glycemic-index, low-fat mirrored desirable balanced human diet for maintaining body weight. Body weight and serum concentrations for fasting glucose (FG, adipokines (leptin and adiponectin, and proinflammatory cytokines [monocyte chemoattractant protein-1 (MCP-1 and tumor necrosis factor-α (TNF-α] were measured. Rats were surgically implanted with C40 transmitters and blood pressure (BP-both systolic; SBP and diastolic; DBP and heart rate (HR were recorded by telemetry every 5 minutes during both sleep (day and active (night periods. Pulse pressure (PP was calculated (PP = SBP-DBP. Results [mean(SEM]: The AD fed group displayed significant increase in body weight (after 90 days; p Conclusion These data validate our stated hypothesis that systemic inflammation and glycemia influence circadian blood pressure variability. This study, for the first time, demonstrates a cause and effect relationship between caloric excess, enhanced systemic inflammation, dysglycemia, loss of blood pressure control and abnormal CBPV. Our results provide the fundamental basis for examining the relationship between dysglycemia and perturbation of the underlying mechanisms (adipose tissue dysfunction induced local and systemic inflammation, insulin resistance and alteration of adipose tissue precursors for the renin-aldosterone-angiotensin system which generate abnormal CBPV.

  5. Avoiding unplanned resections of wrist sarcomas: an algorithm for evaluating dorsal wrist masses.

    Science.gov (United States)

    Crosby, Samuel N; Alamanda, Vignesh K; Weikert, Douglas R; Holt, Ginger E

    2013-09-01

    Ganglion cysts, soft-tissue masses that commonly occur about the wrist, are often excised without imaging or biopsy. In this article, we report a series of incompletely excised soft-tissue sarcomas about the wrist and offer an algorithm for their evaluation. We describe a series of 4 consecutive patients who each presented after incomplete resection of a soft-tissue sarcoma mistakenly diagnosed as a ganglion cyst. We also retrospectively review the cases of 7 patients with incompletely excised sarcomas of the wrist. Three of the 4 patients with sarcomas mistaken for ganglion cysts did not have prior magnetic resonance imaging (MRI), 3 of the 4 did not have an attempted aspiration, and all 4 did not have transillumination. Common atypical characteristics included ulna-based lesions (3/4), symptoms for less than 6 months (3/4), and no appreciable fluctuation in size (3/4). Functional outcomes for all patients were poor because of multiple surgical procedures, re-excisions requiring flaps, and need for additional adjuvant therapies. Dorsal wrist masses with atypical characteristics should be approached with caution. Transillumination and aspiration are 2 accessible, cost-efficient methods for evaluating these masses. If either test is abnormal, an MRI should be performed. PMID:24078963

  6. The paediatric wrist revisited - findings of bony depressions in healthy children on radiographs compared to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Avenarius, Derk M.F.; Eldevik, Petter [University Hospital North Norway, Department of Radiology, Tromsoe (Norway); Ording Mueller, Lil-Sofie [University Hospital North Norway, Department of Radiology, Tromsoe (Norway); Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Owens, Catherine M. [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom); Rosendahl, Karen [Haukeland University Hospital, Department of Radiology, Bergen (Norway); University of Bergen, Department of Surgical Sciences, Bergen (Norway); Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom)

    2012-07-15

    The presence of erosions is used for diagnosis and monitoring of disease activity in juvenile idiopathic arthritis (JIA). Assessment of carpal bone erosions in children is challenging due to lack of normal references. To define normal appearances of bony depressions in the wrist on radiographs and MRI. MRI and radiography of the wrist were performed in 88 healthy children, 5-15 years of age. We assessed the number of bony depressions within the carpals/proximal metacarpals on both modalities, separately and combined. A total of 75 carpal depressions were identified on radiography compared to 715 on MRI. The number of bony depressions identified radiographically showed no statistically significant difference across age-groups. Within the metacarpals, there was no significant difference between bony depressions identified by MRI or radiography, except at the bases of the second metacarpal. Bony depressions that resemble erosions are normal findings in the wrist in children. MRI identifies more depressions than radiographs in the carpus. Some bony depressions occur at typical locations and should be accounted for when assessing the wrist in JIA to avoid overstaging. (orig.)

  7. Dynamic contrast-enhanced magnetic resonance imaging of the wrist in early arthritis

    Directory of Open Access Journals (Sweden)

    M.A. Cimmino

    2011-09-01

    Full Text Available Objectives: MRI has been proposed as the imaging method of choice to evaluate the long-term outcome in patients with early arthritis. The role of dynamic MRI, performed at presentation, in predicting the outcome of patients with early arthritis has been addressed in the present study. Methods: 39 patients with early arthritis, involving at least one wrist, were studied with clinical visits and laboratory investigations, every 3 months. Dynamic MRI was performed with a low-field (0.2T, extremity-dedicated machine (Artoscan, Esaote, Genova, Italy equipped with a permanent magnet and with a dedicated hand and wrist coil. During the intravenous injection of Gd-DTPA, twenty consecutive fast images of 3 slices of the wrist were acquired. The synovial contrast enhancement ratio was calculated both as rate of early enhancement (REE per second during the first 55” and as relative enhancement (RE at t seconds. Results: In our cohort of patients, REE and RE were significantly lower than those observed in a historical cohort of 36 patients with active rheumatoid arthritis. In univariate analysis, low RE predicted complete remission of arthritis. In multivariate analysis, fulfillment of RA criteria during follow-up was predicted by high RE. The need for immunosuppressive treatment at the end of follow-up was predicted by both low RE and high REE. Conclusions: Dynamic MRI may be used to predict several outcomes of early arthritis involving the wrist

  8. Supinator Extender (SUE): a pneumatically actuated robot for forearm/wrist rehabilitation after stroke.

    Science.gov (United States)

    Allington, James; Spencer, Steven J; Klein, Julius; Buell, Meghan; Reinkensmeyer, David J; Bobrow, James

    2011-01-01

    The robot described in this paper, SUE (Supinator Extender), adds forearm/wrist rehabilitation functionality to the UCI BONES exoskeleton robot and to the ArmeoSpring rehabilitation device. SUE is a 2-DOF serial chain that can measure and assist forearm supination-pronation and wrist flexion-extension. The large power to weight ratio of pneumatic actuators allows SUE to achieve the forces needed for rehabilitation therapy while remaining lightweight enough to be carried by BONES and ArmeoSpring. Each degree of freedom has a range of 90 degrees, and a nominal torque of 2 ft-lbs. The cylinders are mounted away from the patient's body on the lateral aspect of the arm. This is to prevent the danger of a collision and maximize the workspace of the arm robot. The rotation axis used for supination-pronation is a small bearing just below the subject's wrist. The flexion-extension motion is actuated by a cantilevered pneumatic cylinder, which allows the palm of the hand to remain open. Data are presented that demonstrate the ability of SUE to measure and cancel forearm/wrist passive tone, thereby extending the active range of motion for people with stroke. PMID:22254624

  9. The paediatric wrist revisited - findings of bony depressions in healthy children on radiographs compared to MRI

    International Nuclear Information System (INIS)

    The presence of erosions is used for diagnosis and monitoring of disease activity in juvenile idiopathic arthritis (JIA). Assessment of carpal bone erosions in children is challenging due to lack of normal references. To define normal appearances of bony depressions in the wrist on radiographs and MRI. MRI and radiography of the wrist were performed in 88 healthy children, 5-15 years of age. We assessed the number of bony depressions within the carpals/proximal metacarpals on both modalities, separately and combined. A total of 75 carpal depressions were identified on radiography compared to 715 on MRI. The number of bony depressions identified radiographically showed no statistically significant difference across age-groups. Within the metacarpals, there was no significant difference between bony depressions identified by MRI or radiography, except at the bases of the second metacarpal. Bony depressions that resemble erosions are normal findings in the wrist in children. MRI identifies more depressions than radiographs in the carpus. Some bony depressions occur at typical locations and should be accounted for when assessing the wrist in JIA to avoid overstaging. (orig.)

  10. Volar Central Portal in Wrist Arthroscopy.

    Science.gov (United States)

    Corella, F; Ocampos, M; Cerro, M Del; Larrainzar-Garijo, R; Vázquez, T

    2016-03-01

    Background Nowadays, the wrist is not limited to a dorsal visualization; the joint can be thought of as a "box," which can be visualized from almost every perspective. The purpose of this study was to describe a new volar central portal for the wrist, following three principles: a single incision that allows access to both the radiocarpal and midcarpal joints, centered on the lunate, with the volar structures at risk protected not only by retractors, but also by tendons. Description of Technique The incision begins in the distal wrist crease and extended 1.5 cm proximally up to the proximal wrist crease, following the axis of the third intermetacarpal space. The flexor superficialis tendons are identified and retracted toward the radial side. Next, the fourth and fifth flexor digitorum profundus tendons are retracted toward the ulnar side, while the third and second tendons are retracted toward the radial side. The volar central midcarpal portal is performed under direct vision just over the anterior horn of the lunate through the Poirier space. The volar central radiocarpal portal is created under the lunate through the interval between the ulnocarpal ligaments and the short radioulnar ligament. Methods An anatomical study was performed on 14 cadaver specimens. Two data were recorded: iatrogenic injuries of the structures at risk and the distances to the structures at risk. Results The median (interquartile range [IQR]) distances from the volar central radiocarpal portal to the median nerve, palmar cutaneous branch of the median nerve, and ulnar neurovascular bundle were 10.5 (7.8-15.0), 18.5 (15.8-20.3), and 7.0 (5.0-10.5) mm, respectively. The median (IQR) distances from the volar central midcarpal portal to the median nerve, palmar cutaneous branch of the median nerve, and ulnar neurovascular bundle were 7.0 (4.8-10.3), 16.0 (14.8-19.0), and 4.5 (3.8-9.0) mm, respectively. No iatrogenic injuries were observed. Conclusion The volar central portal is

  11. Prosthesis of the wrist-joint

    Energy Technology Data Exchange (ETDEWEB)

    Feldmeier, C.

    1983-02-25

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated.

  12. Prosthesis of the wrist-joint

    International Nuclear Information System (INIS)

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated. (orig.)

  13. Wrist-worn pervasive gaze interaction

    DEFF Research Database (Denmark)

    Hansen, John Paulin; Lund, Haakon; Biermann, Florian; Møllenbach, Emilie; Sztuk, Sebastian; San Augustin, javier

    This paper addresses gaze interaction for smart home control, conducted from a wrist-worn unit. First we asked ten people to enact the gaze movements they would propose for e.g. opening a door or adjusting the room temperature. On basis of their suggestions we built and tested different versions of...... correct selection. Their subjective evaluations were positive with regard to the speed of the interaction. We conclude that gaze gesture input seems feasible for fast and brief remote control of smart home technology provided that robustness of tracking is improved....

  14. Predicted Role of NAD Utilization in the Control of Circadian Rhythms during DNA Damage Response.

    Directory of Open Access Journals (Sweden)

    Augustin Luna

    2015-05-01

    Full Text Available The circadian clock is a set of regulatory steps that oscillate with a period of approximately 24 hours influencing many biological processes. These oscillations are robust to external stresses, and in the case of genotoxic stress (i.e. DNA damage, the circadian clock responds through phase shifting with primarily phase advancements. The effect of DNA damage on the circadian clock and the mechanism through which this effect operates remains to be thoroughly investigated. Here we build an in silico model to examine damage-induced circadian phase shifts by investigating a possible mechanism linking circadian rhythms to metabolism. The proposed model involves two DNA damage response proteins, SIRT1 and PARP1, that are each consumers of nicotinamide adenine dinucleotide (NAD, a metabolite involved in oxidation-reduction reactions and in ATP synthesis. This model builds on two key findings: 1 that SIRT1 (a protein deacetylase is involved in both the positive (i.e. transcriptional activation and negative (i.e. transcriptional repression arms of the circadian regulation and 2 that PARP1 is a major consumer of NAD during the DNA damage response. In our simulations, we observe that increased PARP1 activity may be able to trigger SIRT1-induced circadian phase advancements by decreasing SIRT1 activity through competition for NAD supplies. We show how this competitive inhibition may operate through protein acetylation in conjunction with phosphorylation, consistent with reported observations. These findings suggest a possible mechanism through which multiple perturbations, each dominant during different points of the circadian cycle, may result in the phase advancement of the circadian clock seen during DNA damage.

  15. Interaction of circadian clock proteins PER2 and CRY with BMAL1 and CLOCK

    OpenAIRE

    Bordon Alain; Tallone Tiziano; Langmesser Sonja; Rusconi Sandro; Albrecht Urs

    2008-01-01

    Abstract Background Circadian oscillation of clock-controlled gene expression is mainly regulated at the transcriptional level. Heterodimers of CLOCK and BMAL1 act as activators of target gene transcription; however, interactions of PER and CRY proteins with the heterodimer abolish its transcriptional activation capacity. PER and CRY are therefore referred to as negative regulators of the circadian clock. To further elucidate the mechanism how positive and negative components of the clock int...

  16. Circadian malfunctions in depression - neurobiological and psychosocial approaches.

    Science.gov (United States)

    Nechita, Florina; Pîrlog, Mihail Cristian; ChiriŢă, Anca Livia

    2015-01-01

    Depression leads to disturbances in physiological rhythms, which result in disturbances in circadian sleep-wake cycles, hormonal secretion patterns and fluctuations in mood, all of which can be objectively measured. These disturbances, which are associated with depression, can be also used to define depression. Beyond these "transversal" time-related symptoms, there are the "longitudinal" time-related symptoms, since depression evolves over a long period of time, with a profound impact on a person's life and is often associated with long-term psychosocial consequences (Mendlewicz, 2010). The circadian rhythm reflects an approximate 24-hour cycle in the biochemical, physiological and behavioral processes of living entities, which crucially influences human well-being and health. Increasing evidence from clinical and neurobiological research suggests that disrupted temporal organization impairs behavior, cognition, mood, sleep and social activity and may be implicated in mental disorders. It has been proposed that circadian malfunction is a major core feature of mood disorders, depression in particular. In depressed patients, circadian rhythms and homeostatic processes are disrupted, thereby affecting mood, sleep, activity and a variety of biological functions such as hormone secretion and body temperature (Hajak & Landgrebe, 2010). Sleep difficulties are among the most current symptoms in depressed patients. Insomnia is often the reason why depressed patients seek help and relief of sleep disturbance may encourage compliance with antidepressant treatment. Apart from the discomfort that sleep problems produce, they may lead to exhaustion, poor functioning and they are associated with an increase in suicide risk (Wilson et al., 2013). PMID:26662127

  17. Estimation of Thermal Sensation Based on Wrist Skin Temperatures

    Science.gov (United States)

    Sim, Soo Young; Koh, Myung Jun; Joo, Kwang Min; Noh, Seungwoo; Park, Sangyun; Kim, Youn Ho; Park, Kwang Suk

    2016-01-01

    Thermal comfort is an essential environmental factor related to quality of life and work effectiveness. We assessed the feasibility of wrist skin temperature monitoring for estimating subjective thermal sensation. We invented a wrist band that simultaneously monitors skin temperatures from the wrist (i.e., the radial artery and ulnar artery regions, and upper wrist) and the fingertip. Skin temperatures from eight healthy subjects were acquired while thermal sensation varied. To develop a thermal sensation estimation model, the mean skin temperature, temperature gradient, time differential of the temperatures, and average power of frequency band were calculated. A thermal sensation estimation model using temperatures of the fingertip and wrist showed the highest accuracy (mean root mean square error [RMSE]: 1.26 ± 0.31). An estimation model based on the three wrist skin temperatures showed a slightly better result to the model that used a single fingertip skin temperature (mean RMSE: 1.39 ± 0.18). When a personalized thermal sensation estimation model based on three wrist skin temperatures was used, the mean RMSE was 1.06 ± 0.29, and the correlation coefficient was 0.89. Thermal sensation estimation technology based on wrist skin temperatures, and combined with wearable devices may facilitate intelligent control of one’s thermal environment. PMID:27023538

  18. [A woman with acute pain and swelling of her wrist

    NARCIS (Netherlands)

    Ridder, J.A. de; Koning, G.G.

    2015-01-01

    After hyperextension of both her wrists, a 39-year-old woman, who used coumarin derivatives for a known antiphospholipid syndrome, had acute pain and swelling of the left wrist. She had symptoms of an acute carpal tunnel syndrome. MRI revealed a hematoma compressing the median nerve in the carpal tu

  19. 21 CFR 888.3780 - Wrist joint polymer constrained prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint polymer constrained prosthesis. 888.3780 Section 888.3780 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... constrained prosthesis. (a) Identification. A wrist joint polymer constrained prosthesis is a device made...

  20. A Standardized Protocol for Cone-Beam Computed Tomography of the Hand and Wrist in Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    D.V. Makarova

    2015-12-01

    Full Text Available The aim of the investigation was to develop a standardized protocol for description of the results of cone-beam computed tomography (CBCT of the hand and wrist in rheumatoid arthritis. Materials and Methods. The results of 112 hand and wrist CBCT examinations (n=56 were analyzed in patients aged from 36 to 67 with medium-active seropositive rheumatoid arthritis in anamnesis. The hand and wrist CBCT was carried out using a NewTom 5G cone-beam computed unit (QR s.r.l., Italy having a 200×250 mm flat-panel detector, 180×160 mm field of view (maximum, and a 360° gantry rotation around the region of interest. The hand and wrist scanning was carried out from the distal metaphysis of the forearm bones to the nail ends of the distal phalanges of the fingers. Scan mode — patient scan (exposure time — 3.6 s, X-ray tube boosting voltage — 110 kW, current — 0.6‒0.8 mA, scan pattern — regular scan, scan time — 18 s. The CBCT examinations of the wrists and hands were performed using special-purpose setups allowing complete coverage of the region of interest. Results. A standardized protocol was designed for the description of hand and wrist cone-beam examination that documents all the major changes resulting from rheumatoid arthritis: soft tissue thickening, erosions and cystic-like changes, osteoporosis, narrowing of the joint spaces, incomplete dislocations, bone deformities and areas of osteolysis. Significant changes are recorded in point form, according to the Sharp or SENS methods. Application of the standardized protocol allows unification of the structuring of the examination description, and facilitates X-ray assessment of changes in the hand and wrist during CBCT in patients with rheumatoid arthritis.

  1. Two-degree-of-freedom powered prosthetic wrist

    Directory of Open Access Journals (Sweden)

    Peter J. Kyberd, PhD

    2011-07-01

    Full Text Available Prosthetic wrists need to be compact. By minimizing space requirements, a wrist unit can be made for people with long residual limbs. This prosthetic wrist uses two motors arranged across the arm within the envelope of the hand. The drive is transmitted by a differential so that it produces wrist flexion and extension, pronation and supination, or a combination of both. As a case study, it was controlled by a single-prosthesis user with pattern recognition of the myoelectric signals from the forearm. The result is a compact, two-degree-of-freedom prosthetic wrist that has the potential to improve the functionality of any prosthetic hand by creating a hand orientation that more closely matches grasp requirements.

  2. Radiological diagnosis in lesions of the wrist

    Energy Technology Data Exchange (ETDEWEB)

    Kob, A.; Thelen, R.; Schild, H.; Lang, A.

    1988-05-01

    To visualise the rupture of the scaphoid bone it will be sufficient - as has been proven - to perform two additional projections from the navicular series besides the standard X-rays of the wrist joint, namely, with the hand in writing-pen position and in hyperpronation. With this procedure, almost all (99%) of fractures detected during first examination can be diagnosed. To prove the occurrence of fractures of the wrist besides those of the os naviculare, specific X-rays are employed in accordance with the results of an on-target clinical examination. Such X-rays are, in particular, lateral radioulnar X-ray rotated by 10/sup 0/ in volar direction to assess the os triquetrum, lateral radioulnar X-ray in 10-30/sup 0/ supination to visualise the os pisiforme, carpal tunnel X-ray to assess the entire hollow of the hand, in particular the volar parts of os pisiforme, os hamatum (hamulus) and os trapezium. Although such fractures can partly also be diagnosed by means of a navicular series, as already stated, it is not permissible to exclude the presence of a fracture if there are no abnormal findings in the navicular quartet whereas clinical findings are positive.

  3. Radiological diagnosis in lesions of the wrist

    International Nuclear Information System (INIS)

    To visualise the rupture of the scaphoid bone it will be sufficient - as has been proven - to perform two additional projections from the navicular series besides the standard X-rays of the wrist joint, namely, with the hand in writing-pen position and in hyperpronation. With this procedure, almost all (99%) of fractures detected during first examination can be diagnosed. To prove the occurrence of fractures of the wrist besides those of the os naviculare, specific X-rays are employed in accordance with the results of an on-target clinical examination. Such X-rays are, in particular, lateral radioulnar X-ray rotated by 100 in volar direction to assess the os triquetrum, lateral radioulnar X-ray in 10-300 supination to visualise the os pisiforme, carpal tunnel X-ray to assess the entire hollow of the hand, in particular the volar parts of os pisiforme, os hamatum (hamulus) and os trapezium. Although such fractures can partly also be diagnosed by means of a navicular series, as already stated, it is not permissible to exclude the presence of a fracture if there are no abnormal findings in the navicular quartet whereas clinical findings are positive. (orig.)

  4. Basic pathologic conditions of the wrist

    International Nuclear Information System (INIS)

    Pathologic conditions of the wrist involve both musculoskeletal structure (bones and joints) and soft tissues, of which fat pads are an important diagnostic aid to recognize various disorders. The authors report their 5-year experience with Xeroradiography in the diagnosis of various pathologic conditions (e.g., inflammatory, degenerative, and tumoral conditions) of the wrist. The importance of Xeroradiography was emphatized, in the past, because of its characteristic technical properties, especially in demonstrating lower-density tissues tumors. The main advantage of Xeroradiography is the physical phenomenon known as edge effect, which increases image contrast at the borders. Other differences between xeroradiography and conventional radiography are: broader recording latitude of the former, together with its higher resolution power (100 lines/mm), and high exposition power (which makes repeats useless). Thus, Xeroradiography allows the contemporary depiction of various and different structures and densities- e.g., bones and soft tissues. Unfortunately, radiation dose to the patient is higher during Xeroradiography than during conventional radiography. That is why digital radiography has nowadays replaced Xeroradiography. In fact, the former provides images that are comparable with those obtained by means of conventional radiography and -sometimes- even with xeroradiographic images allows radiation dose to the patient to be markedly reduced, whereas recording latitude remains the same

  5. Partitioning circadian transcription by SIRT6 leads to segregated control of cellular metabolism.

    Science.gov (United States)

    Masri, Selma; Rigor, Paul; Cervantes, Marlene; Ceglia, Nicholas; Sebastian, Carlos; Xiao, Cuiying; Roqueta-Rivera, Manuel; Deng, Chuxia; Osborne, Timothy F; Mostoslavsky, Raul; Baldi, Pierre; Sassone-Corsi, Paolo

    2014-07-31

    Circadian rhythms are intimately linked to cellular metabolism. Specifically, the NAD(+)-dependent deacetylase SIRT1, the founding member of the sirtuin family, contributes to clock function. Whereas SIRT1 exhibits diversity in deacetylation targets and subcellular localization, SIRT6 is the only constitutively chromatin-associated sirtuin and is prominently present at transcriptionally active genomic loci. Comparison of the hepatic circadian transcriptomes reveals that SIRT6 and SIRT1 separately control transcriptional specificity and therefore define distinctly partitioned classes of circadian genes. SIRT6 interacts with CLOCK:BMAL1 and, differently from SIRT1, governs their chromatin recruitment to circadian gene promoters. Moreover, SIRT6 controls circadian chromatin recruitment of SREBP-1, resulting in the cyclic regulation of genes implicated in fatty acid and cholesterol metabolism. This mechanism parallels a phenotypic disruption in fatty acid metabolism in SIRT6 null mice as revealed by circadian metabolome analyses. Thus, genomic partitioning by two independent sirtuins contributes to differential control of circadian metabolism. PMID:25083875

  6. Emergence of noise-induced oscillations in the central circadian pacemaker.

    Directory of Open Access Journals (Sweden)

    Caroline H Ko

    Full Text Available Bmal1 is an essential transcriptional activator within the mammalian circadian clock. We report here that the suprachiasmatic nucleus (SCN of Bmal1-null mutant mice, unexpectedly, generates stochastic oscillations with periods that overlap the circadian range. Dissociated SCN neurons expressed fluctuating levels of PER2 detected by bioluminescence imaging but could not generate circadian oscillations intrinsically. Inhibition of intercellular communication or cyclic-AMP signaling in SCN slices, which provide a positive feed-forward signal to drive the intracellular negative feedback loop, abolished the stochastic oscillations. Propagation of this feed-forward signal between SCN neurons then promotes quasi-circadian oscillations that arise as an emergent property of the SCN network. Experimental analysis and mathematical modeling argue that both intercellular coupling and molecular noise are required for the stochastic rhythms, providing a novel biological example of noise-induced oscillations. The emergence of stochastic circadian oscillations from the SCN network in the absence of cell-autonomous circadian oscillatory function highlights a previously unrecognized level of circadian organization.

  7. NPAS2 Compensates for Loss of CLOCK in Peripheral Circadian Oscillators.

    Directory of Open Access Journals (Sweden)

    Dominic Landgraf

    2016-02-01

    Full Text Available Heterodimers of CLOCK and BMAL1 are the major transcriptional activators of the mammalian circadian clock. Because the paralog NPAS2 can substitute for CLOCK in the suprachiasmatic nucleus (SCN, the master circadian pacemaker, CLOCK-deficient mice maintain circadian rhythms in behavior and in tissues in vivo. However, when isolated from the SCN, CLOCK-deficient peripheral tissues are reportedly arrhythmic, suggesting a fundamental difference in circadian clock function between SCN and peripheral tissues. Surprisingly, however, using luminometry and single-cell bioluminescence imaging of PER2 expression, we now find that CLOCK-deficient dispersed SCN neurons and peripheral cells exhibit similarly stable, autonomous circadian rhythms in vitro. In CLOCK-deficient fibroblasts, knockdown of Npas2 leads to arrhythmicity, suggesting that NPAS2 can compensate for loss of CLOCK in peripheral cells as well as in SCN. Our data overturn the notion of an SCN-specific role for NPAS2 in the molecular circadian clock, and instead indicate that, at the cellular level, the core loops of SCN neuron and peripheral cell circadian clocks are fundamentally similar.

  8. PPARα is a potential therapeutic target of drugs to treat circadian rhythm sleep disorders

    International Nuclear Information System (INIS)

    Recent progress at the molecular level has revealed that nuclear receptors play an important role in the generation of mammalian circadian rhythms. To examine whether peroxisome proliferator-activated receptor alpha (PPARα) is involved in the regulation of circadian behavioral rhythms in mammals, we evaluated the locomotor activity of mice administered with the hypolipidemic PPARα ligand, bezafibrate. Circadian locomotor activity was phase-advanced about 3 h in mice given bezafibrate under light-dark (LD) conditions. Transfer from LD to constant darkness did not change the onset of activity in these mice, suggesting that bezafibrate advanced the phase of the endogenous clock. Surprisingly, bezafibrate also advanced the phase in mice with lesions of the suprachiasmatic nucleus (SCN; the central clock in mammals). The circadian expression of clock genes such as period2, BMAL1, and Rev-erbα was also phase-advanced in various tissues (cortex, liver, and fat) without affecting the SCN. Bezafibrate also phase-advanced the activity phase that is delayed in model mice with delayed sleep phase syndrome (DSPS) due to a Clock gene mutation. Our results indicated that PPARα is involved in circadian clock control independently of the SCN and that PPARα could be a potent target of drugs to treat circadian rhythm sleep disorders including DSPS

  9. Effect of melatonin on endogenous circadian rhythm

    Institute of Scientific and Technical Information of China (English)

    XU Feng; WANG Min; ZANG Ling-he

    2008-01-01

    Objective To further authenticate the role of melatonin on endogenous biologic clock system. Methods Pinealectomized mice were used in the experiments, a series of circadian rhythm of physiology index, such as glucocorticoid, amino acid neurotransmitter, immune function, sensitivity of algesia and body temperature were measured. Results Effects of melatonin on endogenous circadian rhythm roughly appeared four forms: 1) The model of inherent rhythm was invariant, but midvalue was removed. 2) Pacing function: pinealectomy and melatonin administration changed amplitude of the circadian vibration of aspartate, peripheral blood WBC and serum hemolysin. 3) Phase of rhythm changed, such as the effects on percentage of lymphocyte and sensitivity of algesia. 4) No effect, the circadian rhythm of body temperature belong to this form Conclusions Melatonin has effects some circadian rhythm, and it can adjust endogenous inherent rhythm and make the rhythm keep step with environmental cycle. Melatonin may be a kind of Zeitgeber, Pineal gland might being a rhythm bearing organ to some circadian rhythm.

  10. Circadian secretion patterns of ß-endorphin and leucine enkephalin

    Directory of Open Access Journals (Sweden)

    E. H. de Wet

    1992-07-01

    Full Text Available ß-endorphin and leucine enkephalin are neuropeptides with potent opioid activity. In a study to investigate the circadian secretion patterns of the above-mentioned, blood samples were collected hourly from 12 healthy males who were subjected to the experiment for 24 hours. Radioimmunoassays were used in the analysis of plasma samples for ß-endorphin and leucine enkephalin. Peak concentrations of ß-endorphin were demonstrated from 08:00-09:00, while peak concentrations of leucine enkephalin occured from 23:00-07:00. Trough concentrations of ß-endorphin occurred from 24:00-05:00, while trough con­centrations of leucine enkephalin were demonstrated from 09:00-12:00. The illustrated circadian secretion pattern for ß-endorphin simulates the well-known circadian rhythm of cortisol. The answer to this may be in the fact that ß-endorphin and corticotropin stem from the same precursor. The illustrated circadian secretion pattern for leucine enkephalin simulates that of melatonin. The reason for this is unclear.

  11. Stochastic Simulation of Delay-Induced Circadian Rhythms in Drosophila

    Directory of Open Access Journals (Sweden)

    Xu Zhouyi

    2009-01-01

    Full Text Available Circadian rhythms are ubiquitous in all eukaryotes and some prokaryotes. Several computational models with or without time delays have been developed for circadian rhythms. Exact stochastic simulations have been carried out for several models without time delays, but no exact stochastic simulation has been done for models with delays. In this paper, we proposed a detailed and a reduced stochastic model with delays for circadian rhythms in Drosophila based on two deterministic models of Smolen et al. and employed exact stochastic simulation to simulate circadian oscillations. Our simulations showed that both models can produce sustained oscillations and that the oscillation is robust to noise in the sense that there is very little variability in oscillation period although there are significant random fluctuations in oscillation peeks. Moreover, although average time delays are essential to simulation of oscillation, random changes in time delays within certain range around fixed average time delay cause little variability in the oscillation period. Our simulation results also showed that both models are robust to parameter variations and that oscillation can be entrained by light/dark circles. Our simulations further demonstrated that within a reasonable range around the experimental result, the rates that dclock and per promoters switch back and forth between activated and repressed sites have little impact on oscillation period.

  12. Circadian remodeling of neuronal circuits involved in rhythmic behavior.

    Directory of Open Access Journals (Sweden)

    María Paz Fernández

    2008-03-01

    Full Text Available Clock output pathways are central to convey timing information from the circadian clock to a diversity of physiological systems, ranging from cell-autonomous processes to behavior. While the molecular mechanisms that generate and sustain rhythmicity at the cellular level are well understood, it is unclear how this information is further structured to control specific behavioral outputs. Rhythmic release of pigment dispersing factor (PDF has been proposed to propagate the time of day information from core pacemaker cells to downstream targets underlying rhythmic locomotor activity. Indeed, such circadian changes in PDF intensity represent the only known mechanism through which the PDF circuit could communicate with its output. Here we describe a novel circadian phenomenon involving extensive remodeling in the axonal terminals of the PDF circuit, which display higher complexity during the day and significantly lower complexity at nighttime, both under daily cycles and constant conditions. In support to its circadian nature, cycling is lost in bona fide clockless mutants. We propose this clock-controlled structural plasticity as a candidate mechanism contributing to the transmission of the information downstream of pacemaker cells.

  13. The relationship between circadian disruption and the development of metabolic syndrome and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Karatsoreos IN

    2014-12-01

    Full Text Available Ilia N Karatsoreos Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA, USA Abstract: Circadian (daily rhythms are pervasive in nature, and expressed in nearly every behavioral and physiological process. In mammals, circadian rhythms are regulated by the master brain clock in the suprachiasmatic nucleus of the hypothalamus that coordinates the activity of “peripheral” oscillators throughout the brain and body. While much progress has been made in understanding the basic functioning of the circadian clock at the level of genes, molecules, and cells, our understanding of how these clocks interact with complex systems is still in its infancy. Much recent work has focused on the role of circadian clocks in the etiology of disorders as diverse as cancer, diabetes, and obesity. Given the rapid rise in obesity, and the economic costs involved in treating its associated cardiometabolic disorders such as heart disease and diabetes mellitus, understanding the development of obesity and metabolic dysregulation is crucial. Significant epidemiological data indicate a role for circadian rhythms in metabolic disorders. Shift workers have a higher incidence of obesity and diabetes, and laboratory studies in humans show misaligning sleep and the circadian clock leads to hyperinsulinemia. In animal models, body-wide “clock gene” knockout mice are prone to obesity. Further, disrupting the circadian clock by manipulating the light–dark cycle can result in metabolic dysregulation and development of obesity. At the molecular level, elegant studies have shown that targeted disruption of the genetic circadian clock in the pancreas leads to diabetes, highlighting the fact that the circadian clock is directly coupled to metabolism at the cellular level. Keywords: glucose, metabolism, sleep, rhythms, obesity

  14. Metabolic consequences of sleep and circadian disorders

    OpenAIRE

    Depner, Christopher M.; Stothard, Ellen R.; Wright, Kenneth P.

    2014-01-01

    Sleep and circadian rhythms modulate or control daily physiological patterns with importance for normal metabolic health. Sleep deficiencies associated with insufficient sleep schedules, insomnia with short-sleep duration, sleep apnea, narcolepsy, circadian misalignment, shift work, night eating syndrome and sleep-related eating disorder may all contribute to metabolic dysregulation. Sleep deficiencies and circadian disruption associated with metabolic dysregulation may contribute to weight g...

  15. Unraveling the circadian clock in Arabidopsis

    OpenAIRE

    Wang, Xiaoxue; Ma, Ligeng

    2012-01-01

    The circadian clock is an endogenous timing system responsible for coordinating an organism’s biological processes with its environment. Interlocked transcriptional feedback loops constitute the fundamental architecture of the circadian clock. In Arabidopsis, three feedback loops, the core loop, morning loop and evening loop, comprise a network that is the basis of the circadian clock. The components of these three loops are regulated in distinct ways, including transcriptional, post-transcri...

  16. Circadian regulators of intestinal lipid absorption

    OpenAIRE

    Hussain, M. Mahmood; Pan, Xiaoyue

    2015-01-01

    Among all the metabolites present in the plasma, lipids, mainly triacylglycerol and diacylglycerol, show extensive circadian rhythms. These lipids are transported in the plasma as part of lipoproteins. Lipoproteins are synthesized primarily in the liver and intestine and their production exhibits circadian rhythmicity. Studies have shown that various proteins involved in lipid absorption and lipoprotein biosynthesis show circadian expression. Further, intestinal epithelial cells express circa...

  17. Ultrasound Color Doppler Image Segmentation and Feature Extraction in MCP and Wrist Region in Evaluation of Rheumatoid Arthritis.

    Science.gov (United States)

    Snekhalatha, U; Muthubhairavi, V; Anburajan, M; Gupta, Neelkanth

    2016-09-01

    The present study focuses on automatically to segment the blood flow pattern of color Doppler ultrasound in hand region of rheumatoid arthritis patients and to correlate the extracted the statistical features and color Doppler parameters with standard parameters. Thirty patients with rheumatoid arthritis (RA) and their total of 300 joints of both the hands, i.e., 240 MCP and 60 wrists were examined in this study. Ultrasound color Doppler of both the hands of all the patients was obtained. Automated segmentation of color Doppler image was performed using color enhancement scaling based segmentation algorithm. The region of interest is fixed in the MCP joints and wrist of the hand. Features were extracted from the defined ROI of the segmented output image. The color fraction was measured using Mimics software. The standard parameters such as HAQ score, DAS 28 score, and ESR was obtained for all the patients. The color fraction tends to be increased in wrist and MCP3 joints which indicate the increased blood flow pattern and color Doppler activity as part of inflammation in hand joints of RA. The ESR correlated significantly with the feature extracted parameters such as mean, standard deviation and entropy in MCP3, MCP4 joint and the wrist region. The developed automated color image segmentation algorithm provides a quantitative analysis for diagnosis and assessment of RA. The correlation study between the color Doppler parameters with the standard parameters provides moral significance in quantitative analysis of RA in MCP3 joint and the wrist region. PMID:27449351

  18. [Radiometric assessment of wrist angle values, linear parameters of the forearm and wrist ratios].

    Science.gov (United States)

    Baczkowski, Bogusław; Mechlińska-Baczkowska, Janina; Lorczyński, Adam

    2006-01-01

    With the device of our own invention suitable for static X-ray examination of the wrist 12 radiographic parameters were evaluated. 100 radiograms regarded normal were analyzed, obtained as a comparative in unilateral wrist trauma patients group. Age of the patients ranged from 18 to 60 years. No comparative studies in regard to sex were performed. Obtained data were statistically analyzed. Subsequent values of the radiometric parameters were obtained: scaphoid-lunate angle (SL) 48.61 degrees, radio-lunate angle (RL): -0.83 degrees, palmar inclination of the distal radius metaphysis (RI): 25.96. The most significant linear parameters measured: ulnar length 0.18 mm, ulnar transposition (UT): 0.339 mm. PMID:17131729

  19. The Drosophila melanogaster circadian pacemaker circuit

    Indian Academy of Sciences (India)

    Vasu Sheeba

    2008-12-01

    As an experimental model system, the fruit fly Drosophila melanogaster has been seminal in shaping our understanding of the circadian clockwork. The wealth of genetic tools at our disposal over the past four decades has enabled discovery of the genetic and molecular bases of circadian rhythmicity. More recently, detailed investigation leading to the anatomical, neurochemical and electrophysiological characterization of the various neuronal subgroups that comprise the circadian machinery has revealed pathways through which these neurons come together to act as a neuronal circuit. Thus the D. melanogaster circadian pacemaker circuit presents a relatively simple and attractive model for the study of neuronal circuits and their functions.

  20. Circadian clocks are designed optimally

    CERN Document Server

    Hasegawa, Yoshihiko

    2014-01-01

    Circadian rhythms are acquired through evolution to increase the chances for survival by synchronizing to the daylight cycle. Reliable synchronization is realized through two trade-off properties: regularity to keep time precisely, and entrainability to synchronize the internal time with daylight. Since both properties have been tuned through natural selection, their adaptation can be formalized in the framework of mathematical optimization. By using a succinct model, we found that simultaneous optimization of regularity and entrainability entails inherent features of the circadian mechanism irrespective of model details. At the behavioral level we discovered the existence of a dead zone, a time during which light pulses neither advance nor delay the clock. At the molecular level we demonstrate the role-sharing of two light inputs, phase advance and delay, as is well observed in mammals. We also reproduce the results of phase-controlling experiments and predict molecular elements responsible for the clockwork...

  1. Non-Ocular Circadian Oscillators and Photoreceptors Modulate Long Term Memory Formation in Aplysia

    OpenAIRE

    Lyons, Lisa C.; Rawashdeh, Oliver; Eskin, Arnold

    2006-01-01

    In Aplysia californica, memory formation for long-term sensitization (LTS) and for a more complex type of associative learning, learning that food is inedible (LFI), is modulated by a circadian clock. For both types of learning, formation of long-term memory occurs during the day and significantly less during the night. Aplysia eyes contain a well-characterized circadian oscillator that is strongly coupled to the locomotor activity rhythm. Thus, the authors hypothesized that the ocular circad...

  2. The circadian cycle: daily rhythms from behaviour to genes: First in the Cycles Review Series

    OpenAIRE

    Merrow, M; Spoelstra, K; T. Roenneberg

    2005-01-01

    The daily recurrence of activity and rest are so common as to seem trivial. However, they reflect a ubiquitous temporal programme called the circadian clock. In the absence of either anatomical clock structures or clock genes, the timing of sleep and wakefulness is disrupted. The complex nature of circadian behaviour is evident in the fact that phasing of the cycle during the day varies widely for individuals, resulting in extremes colloquially called 'larks' and 'owls'. These behavioural osc...

  3. Pregnancy-induced changes in ultradian rhythms persist in circadian arrhythmic Siberian hamsters

    OpenAIRE

    Wang, Z. Yan; Cable, Erin J.; Zucker, Irving; Prendergast, Brian J.

    2014-01-01

    The impact of pregnancy and lactation on ultradian rhythms (URs) and circadian rhythms (CRs) of locomotor activity was assessed in circadian rhythmic and arrhythmic Siberian hamsters maintained in a long-day photoperiod (16 h light/day). Progressive decrements in CR robustness and amplitude over the course of gestation were accompanied by enhanced URs. Dark-phase UR period and amplitude increased during early gestation and complexity and robustness increased during late gestation. The persist...

  4. Sex difference in the near-24-hour intrinsic period of the human circadian timing system

    OpenAIRE

    Duffy, Jeanne F.; Cain, Sean W.; Chang, Anne-Marie; Phillips, Andrew J. K.; Münch, Mirjam Y.; Gronfier, Claude; Wyatt, James K.; Dijk, Derk-Jan; Wright, Kenneth P.; Czeisler, Charles A.

    2011-01-01

    The circadian rhythms of melatonin and body temperature are set to an earlier hour in women than in men, even when the women and men maintain nearly identical and consistent bedtimes and wake times. Moreover, women tend to wake up earlier than men and exhibit a greater preference for morning activities than men. Although the neurobiological mechanism underlying this sex difference in circadian alignment is unknown, multiple studies in nonhuman animals have demonstrated a sex difference in cir...

  5. Design principles underlying circadian clocks.

    OpenAIRE

    Rand, D.A.; Shulgin, B. V.; D. Salazar; Millar, A. J.

    2004-01-01

    A fundamental problem for regulatory networks is to understand the relation between form and function: to uncover the underlying design principles of the network. Circadian clocks present a particularly interesting instance, as recent work has shown that they have complex structures involving multiple interconnected feedback loops with both positive and negative feedback. While several authors have speculated on the reasons for this, a convincing explanation is still lacking.We analyse both t...

  6. Ganglion cysts in the paediatric wrist: magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    The majority of published literature on ganglion cysts in children has been from a surgical perspective, with no dedicated radiologic study yet performed. Our aim was to assess the magnetic resonance (MR) imaging appearance of ganglion cysts in a series of paediatric MR wrist examinations. Ninety-seven consecutive paediatric MR wrist examinations were retrospectively reviewed for the presence of ganglion cysts. Only those studies with wrist ganglia were included. Cysts were assessed for location, size, internal characteristics and secondary effect(s). Forty-one ganglion cysts (2-32 mm in size) were seen in 35/97 (36%) patients (24 female, 11 male), mean age: 13 years 11 months (range: 6 years 3 months-18 years). The majority were palmar (63.4%) with the remainder dorsal. Of the cysts, 43.9% were related to a wrist ligament(s), 36.6% to a joint and 17.1% to the triangular fibrocartilage complex. Of the patients, 91.4% had wrist symptoms: pain (n=29, 82.9%), swelling (n=7, 20%) and/or palpable mass (n=4, 11.4%); 71.4% patients had significant additional wrist abnormalities. Ganglion cysts were frequently found in children referred for wrist MRI. (orig.)

  7. Ganglion cysts in the paediatric wrist: magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Bracken, Jennifer; Bartlett, Murray [Royal Children' s Hospital, Medical Imaging Department, Melbourne, VIC (Australia)

    2013-12-15

    The majority of published literature on ganglion cysts in children has been from a surgical perspective, with no dedicated radiologic study yet performed. Our aim was to assess the magnetic resonance (MR) imaging appearance of ganglion cysts in a series of paediatric MR wrist examinations. Ninety-seven consecutive paediatric MR wrist examinations were retrospectively reviewed for the presence of ganglion cysts. Only those studies with wrist ganglia were included. Cysts were assessed for location, size, internal characteristics and secondary effect(s). Forty-one ganglion cysts (2-32 mm in size) were seen in 35/97 (36%) patients (24 female, 11 male), mean age: 13 years 11 months (range: 6 years 3 months-18 years). The majority were palmar (63.4%) with the remainder dorsal. Of the cysts, 43.9% were related to a wrist ligament(s), 36.6% to a joint and 17.1% to the triangular fibrocartilage complex. Of the patients, 91.4% had wrist symptoms: pain (n=29, 82.9%), swelling (n=7, 20%) and/or palpable mass (n=4, 11.4%); 71.4% patients had significant additional wrist abnormalities. Ganglion cysts were frequently found in children referred for wrist MRI. (orig.)

  8. Clinical impact of MRI in acute wrist fractures

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the clinical impact of MRI in the early diagnosis of wrist trauma. High-resolution MR imaging was performed on a 1.5-T unit (Symphony Quantum, Siemens, Erlangen, Germany) using coronal and axial T1- and T2-weighted fat-saturated turbo-spin-echo sequence via a dedicated wrist coil within a mean of 6.6 days after initial radiographs in 54 patients (56 wrists) with clinical suspicion of wrist fractures and normal plain or indistinct radiographs. Initial radiographs were evaluated independently by two senior radiologists and the hand surgeon without knowledge of the MRI findings. The initial treatment protocol was based on evaluation of plain films and clinical findings by the hand surgeon. Treatment protocol was changed after MRI examination if necessary. In 31 of 56 wrists MRI findings resulted in a change of diagnosis. There were false-positive diagnoses on plain radiographs in nearly one half (n=25) of the patients. False-negative diagnoses on plain radiographs resulted in 6 cases. Magnetic resonance imaging detected additional injuries of soft tissue in more than one third (n=20). In 22 of 56 wrists the period of immobilization could be shortened or ended, in 12 of 56 it was prolonged, and in 3 of 56 a surgical intervention was necessary. In 19 wrists MRI had no therapeutic consequences. Our data demonstrate the high clinical impact of MRI in the detection of acute wrist fractures. We recommend MRI of the wrist immediately on the day of trauma if there is clinical suspicion and normal plain radiographs. Accurate diagnosis by MRI examination within the first days following trauma may reduce economic costs due to shortened immobilization time in cases with a suspected fracture but plain radiographs. (orig.)

  9. Clinical impact of MRI in acute wrist fractures

    Energy Technology Data Exchange (ETDEWEB)

    Mack, Martin G.; Keim, Sabine; Balzer, Joern O.; Schwarz, Wolfram; Hochmuth, Kathrin; Vogl, Thomas J. [Department of Diagnostic and Interventional Radiology, Universitaetsklinikum Frankfurt/Main, Theodor-Stern-Kai 7, 60590 Frankfurt/Main (Germany); Windolf, Joachim [Department of Traumatology and Reconstructive Surgery, University of Hamburg, Martinistrasse 52, 20246 Hamburg (Germany)

    2003-03-01

    The purpose of this study was to evaluate the clinical impact of MRI in the early diagnosis of wrist trauma. High-resolution MR imaging was performed on a 1.5-T unit (Symphony Quantum, Siemens, Erlangen, Germany) using coronal and axial T1- and T2-weighted fat-saturated turbo-spin-echo sequence via a dedicated wrist coil within a mean of 6.6 days after initial radiographs in 54 patients (56 wrists) with clinical suspicion of wrist fractures and normal plain or indistinct radiographs. Initial radiographs were evaluated independently by two senior radiologists and the hand surgeon without knowledge of the MRI findings. The initial treatment protocol was based on evaluation of plain films and clinical findings by the hand surgeon. Treatment protocol was changed after MRI examination if necessary. In 31 of 56 wrists MRI findings resulted in a change of diagnosis. There were false-positive diagnoses on plain radiographs in nearly one half (n=25) of the patients. False-negative diagnoses on plain radiographs resulted in 6 cases. Magnetic resonance imaging detected additional injuries of soft tissue in more than one third (n=20). In 22 of 56 wrists the period of immobilization could be shortened or ended, in 12 of 56 it was prolonged, and in 3 of 56 a surgical intervention was necessary. In 19 wrists MRI had no therapeutic consequences. Our data demonstrate the high clinical impact of MRI in the detection of acute wrist fractures. We recommend MRI of the wrist immediately on the day of trauma if there is clinical suspicion and normal plain radiographs. Accurate diagnosis by MRI examination within the first days following trauma may reduce economic costs due to shortened immobilization time in cases with a suspected fracture but plain radiographs. (orig.)

  10. Favorable results after total wrist arthroplasty

    DEFF Research Database (Denmark)

    Boeckstyns, Michel E. H.; Herzberg, G.; Merser, Søren

    2013-01-01

    -rheumatoid cases) and short follow-up times. Here we report a multicenter series using a third-generation implant with a minimum follow-up time of 5 years. Methods In 2012, data were retrieved from a registry of consecutive wrist operations at 7 centers with units specialized in hand surgery, between 2003 and 2007...... for the whole group were statistically significantly better at follow-up. There were no statistically significant differences between the rheumatoid and the non-rheumatoid patients except for motion, which was better in the non-rheumatoid group. The motion obtained depended on the preoperative motion. Implant...... survival was 0.9 at 5–9 years. Interpretation The clinical results in terms of pain, motion, strength, and function were similar to those in previous reports. The implant survival was 0.9 at 9 years, both in rheumatoid and non-rheumatoid cases, which is an important improvement compared to the earlier...

  11. [Arthroscopy-assisted management of wrist fractures].

    Science.gov (United States)

    Deiler, S; Häberle, S; Quentmeier, P; Biberthaler, P; Ahrens, P

    2013-04-01

    Distal radius fractures are the most common fractures in humans and early surgical intervention with modern plating systems is becoming increasingly more established to avoid secondary dislocation. Even fractures with slight dislocations are adequately stabilized and the affinity for surgical intervention and plating procedures is applied to secure these simple fractures. In this aspect the surgical indications are significantly dependent on X-ray examination results. Further diagnostics with respect to ligamentous and soft tissue injury are the exception although the impact energy which creates osseus fractures is sufficient by far to destroy functional soft tissue, cartilage and ligaments. The ongoing development of wrist arthroscopy enables new possibilities especially concerning concomitant articular involvement of distal radius fractures. Arthroscopy-assisted reduction and stabilization as well as minimally invasive soft tissue repair and loose body removal seem to be adequate methods to improve the surgical treatment of distal radius fractures. PMID:23515646

  12. Circadian rhythm of lactate dehydrogenase in rat testis.

    Science.gov (United States)

    Vermouth, N T; Ponce, R H; Carriazo, C S; Blanco, A

    1984-01-01

    Activity of total lactate dehydrogenase (LDH) and of the isozyme X (LDH X or C4) have been determined at 2 hr intervals during 24 hr cycles in testis of adult rats maintained since birth in a photoperiod of 14 hr light: 10 hr dark. LDH X activity of epididymal sections (caput, corpus and cauda) from the same animals was also determined. Total LDH and LDH X activities in testis exhibited circadian rhythms with different timing. LDH X in the three portions of epididymis showed diurnal variations similar to those in testis. Rats subjected to constant light or constant dark presented marked modifications of LDH X profiles, indicating that the photoperiod plays a synchronizer role. While total soluble proteins did not show variations in testis of rats exposed to the photoperiod, a circadian rhythm was demonstrated in animals maintained in constant light or dark. PMID:6467917

  13. Alterations in circadian rhythms are associated with increased lipid peroxidation in females with bipolar disorder.

    Science.gov (United States)

    Cudney, Lauren E; Sassi, Roberto B; Behr, Guilherme A; Streiner, David L; Minuzzi, Luciano; Moreira, Jose C F; Frey, Benicio N

    2014-05-01

    Disturbances in both circadian rhythms and oxidative stress systems have been implicated in the pathophysiology of bipolar disorder (BD), yet no studies have investigated the relationship between these systems in BD. We studied the impact of circadian rhythm disruption on lipid damage in 52 depressed or euthymic BD females, while controlling for age, severity of depressive symptoms and number of psychotropic medications, compared to 30 healthy controls. Circadian rhythm disruption was determined by a self-report measure (Biological Rhythm Interview of Assessment in Neuropsychiatry; BRIAN), which measures behaviours such as sleep, eating patterns, social rhythms and general activity. Malondialdehyde (MDA) levels were measured as a proxy of lipid peroxidation. We also measured the activity of total and extracellular superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST). Multiple linear regressions showed that circadian rhythm disturbance was independently associated with increased lipid peroxidation in females with BD (p GST activity between bipolar females and controls. Circadian rhythms were not associated with lipid peroxidation in healthy controls, where aging was the only significant predictor. These results suggest an interaction between the circadian system and redox metabolism, in that greater disruption in daily rhythms was associated with increased lipid peroxidation in BD only. Antioxidant enzymes have been shown to follow a circadian pattern of expression, and it is possible that disturbance of sleep and daily rhythms experienced in BD may result in decreased antioxidant defence and therefore increased lipid peroxidation. This study provides a basis for further investigation of the links between oxidative stress and circadian rhythms in the neurobiology of BD. PMID:24438530

  14. Elbow and wrist/hand symptoms among 6,943 computer operators: a 1-year follow-up study (the NUDATA study)

    DEFF Research Database (Denmark)

    Lassen, C. F.; Mikkelsen, S.; Kryger, Ann Isabel; Brandt, L. P.; Overgaard, E.; Thomsen, J. F.; Vilstrup, Imogen; Andersen, JH

    2004-01-01

    BACKGROUND: The aim of this study was to examine relations between computer work aspects and elbow and wrist/hand pain conditions and disorders. METHODS: In a 1-year follow-up study among 6,943 technical assistants and machine technicians self-reported active mouse and keyboard time, ergonomic...... exposures and associations with elbow and wrist/hand pain were determined. Standardized clinical examinations were performed among symptomatic participants at baseline and at follow-up. RESULTS: For continuous duration of mouse time adjusted linear effects were statistically significant for all investigated......, while keyboard exposure showed a threshold effect with 12-month wrist/hand pain at follow-up. Clinical diagnoses were not associated with exposure. CONCLUSIONS: Detailed examination of self-reported exposures showed that mouse and keyboard time predicted elbow and wrist/hand pain from low exposure...

  15. Molecular Mechanisms of Circadian Regulation During Spaceflight

    Science.gov (United States)

    Zanello, S. B.; Boyle, R.

    2012-01-01

    The physiology of both vertebrates and invertebrates follows internal rhythms coordinated in phase with the 24-hour daily light cycle. This circadian clock is governed by a central pacemaker, the suprachiasmatic nucleus (SCN) in the brain. However, peripheral circadian clocks or oscillators have been identified in most tissues. How the central and peripheral oscillators are synchronized is still being elucidated. Light is the main environmental cue that entrains the circadian clock. Under the absence of a light stimulus, the clock continues its oscillation in a free-running condition. In general, three functional compartments of the circadian clock are defined. The vertebrate retina contains endogenous clocks that control many aspects of retinal physiology, including retinal sensitivity to light, neurohormone synthesis (melatonin and dopamine), rod disk shedding, signalling pathways and gene expression. Neurons with putative local circadian rhythm generation are found among all the major neuron populations in the mammalian retina. In the mouse, clock genes and function are more localized to the inner retinal and ganglion cell layers. The photoreceptor, however, secrete melatonin which may still serve a an important circadian signal. The reception and transmission of the non-visual photic stimulus resides in a small subpopulation (1-3%) or retinal ganglion cells (RGC) that express the pigment melanopsin (Opn4) and are called intrisically photoreceptive RGC (ipRGC). Melanopsin peak absorption is at 420 nm and all the axons of the ipRGC reach the SCN. A common countermeasure for circadian re-entrainment utilizes blue-green light to entrain the circadian clock and mitigate the risk of fatigue and health and performance decrement due to circadian rhythm disruption. However, an effective countermeasure targeting the photoreceptor system requires that the basic circadian molecular machinery remains intact during spaceflight. We hypothesize that spaceflight may affect ip

  16. Circadian and pharmacological regulation of casein kinase I in the hamster suprachiasmatic nucleus

    Indian Academy of Sciences (India)

    Patricia V. Agostino; Santiago A. Plano; Diego A. Golombek

    2008-12-01

    In mammals, the mechanism for the generation of circadian rhythms and entrainment by light–dark (LD) cycles resides in the hypothalamic suprachiasmatic nuclei (SCN), and the principal signal that adjusts this biological clock with environmental timing is the light:dark cycle. Within the SCN, rhythms are generated by a complex of molecular feedback loops that regulate the transcription of clock genes, including per and cry. Posttranslational modification plays an essential role in the regulation of biological rhythms; in particular, clock gene phosphorylation by casein kinase I, both epsilon (CKI) and delta (CKI), regulates key molecular mechanisms in the circadian clock. In this paper, we report for the first time that CKI activity undergoes a significant circadian rhythm in the SCN (peaking at circadian time 12, the start of the subjective night), and its pharmacological inhibition alters photic entrainment of the clock, indicating that CKI may be a key element in this pathway.

  17. White Paper: functionality and efficacy of wrist protectors in snowboarding—towards a harmonized international standard

    OpenAIRE

    Michel, Frank I; Schmitt, Kai-Uwe; Greenwald, Richard M.; Russell, Kelly; Simpson, Frank I; Schulz, David; Langran, Mike

    2013-01-01

    The wrist is the most frequently injured body region among snowboarders. Studies have shown that the risk of sustaining a wrist injury can be reduced by wearing wrist protection. Currently, there are a wide variety of wrist protection products for snowboarding on the market that offer a range of protective features. However, there are no minimum performance standards for snowboarding wrist protectors worldwide. The International Society for Skiing Safety convened a task force to develop a Whi...

  18. Profiling molecular and behavioral circadian rhythms in the non-symbiotic sea anemone Nematostella vectensis.

    Science.gov (United States)

    Oren, Matan; Tarrant, Ann M; Alon, Shahar; Simon-Blecher, Noa; Elbaz, Idan; Appelbaum, Lior; Levy, Oren

    2015-01-01

    Endogenous circadian clocks are poorly understood within early-diverging animal lineages. We have characterized circadian behavioral patterns and identified potential components of the circadian clock in the starlet sea anemone, Nematostella vectensis: a model cnidarian which lacks algal symbionts. Using automatic video tracking we showed that Nematostella exhibits rhythmic circadian locomotor activity, which is persistent in constant dark, shifted or disrupted by external dark/light cues and maintained the same rate at two different temperatures. This activity was inhibited by a casein kinase 1δ/ε inhibitor, suggesting a role for CK1 homologue(s) in Nematostella clock. Using high-throughput sequencing we profiled Nematostella transcriptomes over 48 hours under a light-dark cycle. We identified 180 Nematostella diurnally-oscillated transcripts and compared them with previously established databases of adult and larvae of the symbiotic coral Acropora millepora, revealing both shared homologues and unique rhythmic genes. Taken together, this study further establishes Nematostella as a non-symbiotic model organism to study circadian rhythms and increases our understanding about the fundamental elements of circadian regulation and their evolution within the Metazoa. PMID:26081482

  19. A colorful model of the circadian clock.

    Science.gov (United States)

    Reppert, Steven M

    2006-01-27

    The migration of the colorful monarch butterfly provides biologists with a unique model system with which to study the cellular and molecular mechanisms underlying a sophisticated circadian clock. The monarch circadian clock is involved in the induction of the migratory state and navigation over long distances, using the sun as a compass. PMID:16439193

  20. Pinealectomy abolishes circadian behavior and interferes with circadian clock gene oscillations in brain and liver but not retina in a migratory songbird.

    Science.gov (United States)

    Trivedi, Amit Kumar; Malik, Shalie; Rani, Sangeeta; Kumar, Vinod

    2016-03-15

    In songbirds, the pineal gland is part of the multi-oscillatory circadian timing system, with participating component oscillators in the eyes and hypothalamus. This study investigated the role of the pineal gland in development of the nighttime migratory restlessness (Zugunruhe) and generation of circadian gene oscillations in the retina, brain and liver tissues in migratory redheaded buntings (Emberiza bruniceps). Pinealectomized (pinx) and sham-operated buntings entrained to short days (8h light: 16h darkness, 8L:16D) were sequentially exposed for 10days each to stimulatory long days (13L: 11D) and constant dim light (LLdim; a condition that tested circadian rhythm persistence). Whereas activity-rest pattern was monitored continuously, the mRNA expressions of clock genes (bmal1, clock, npas2, per2, cry1, rorα, reverα) were measured in the retina, hypothalamus, telencephalon, optic tectum and liver tissues at circadian times, CT, 1, 6, 13, 17 and 21 (CT 0, activity onset) on day 11 of the LLdim. The absence of the pineal gland did not affect the development of long-day induced Zugunruhe but caused decay of the circadian rhythm in Zugunruhe as well as the clock gene oscillations in the hypothalamus, but not in the retina. Further, there were variable effects of pinealectomy in the peripheral brain and liver tissue circadian gene oscillations, notably the persistence of per 2 and cry1 (optic tectum), rorα (telencephalon) and npas2 (liver) mRNA oscillations in pinx birds. We suggest the pineal gland dependence of the generation of circadian gene oscillations in the hypothalamus, not retina, and peripheral brain and liver tissues in migratory redheaded buntings. PMID:26801391

  1. The post-arthro-CT of the wrist clinical evaluation

    CERN Document Server

    Scheurecker, G

    2001-01-01

    To compare the diagnostic effectiveness of post-arthro-CT (PACT) and 3-compartment wrist arthrography (AG) both separate and combined versus wrist arthroscopy for scapho-lunate ligament (SLL), luno-triquetral ligament (LTL) and triangular fibrocartilage (TFC) defects and chondromalacia of the carpal bones. Material and methods: in 58 patients (16-69 years) the affected wrist was examined initially by conventional 3-compartment wrist arthrography with digital subtraction technique during injection followed by digital stress images. Afterwards spiral arthro-CT was performed in the semi-coronal and axial plane with 1 mm slice thickness and secondary true-coronal and sagittal reconstructions. Within 1 month arthroscopy was performed in general anesthesia utilizing standard joint entry points combined with routine digital picture archiving. All examinations were evaluated for SLL, LTL and TFC defects, PACT and AS for ChM too. Results: AG versus AS: the following detection rates were observed (AG and AS positive/AG...

  2. Wrist Energy Fuzzy Assist Cancer Engine – WE-FACE

    Directory of Open Access Journals (Sweden)

    Sharmila Begum M

    2013-04-01

    Full Text Available Promotion and propagation of Ancient Indian Medical System has been our aim, as we foresee the usefulness and cost effectiveness of traditional medical system. Even though there has been a tremendousadvancement in medical technology, the prediction or diagnosis of diseases are costlier than the treatment.Intelligence can be spotted out in each and every cell in an human body and this intelligence gets communicated throughout the body in the form of vibration which can be examined through Wrist Pulse Examination. Since this wrist pulse signals contains vital information which explicitly points out the pathologic changes in a human body. Here, we propose a new methodology named “Wrist Energy Fuzzy Assist Cancer Engine – WE-FACE”for prediction and diagnosis of diseases using fuzzy logic. We mainly focus on the prediction and diagnosis of cancer through wrist pulse signals with the use of appropriate sensors.

  3. Hand and wrist arthritis of Behcet disease: Imaging features

    International Nuclear Information System (INIS)

    Background: Reports on arthritis in Behcet disease are relatively scarce, and imaging features vary. Purpose: To document the various imaging features of articular disorders of the hand and wrist in Behcet disease. Material and Methods: Four patients, four women aged 26 to 65 years, fulfilling the diagnostic criteria of Behcet disease, with imaging findings of hand and wrist arthritis, were seen in two institutions. Radiography and magnetic resonance (MR) imaging were studied to elucidate the pattern and distribution. Results: Both non-erosive arthritis and erosive arthritis of different features were noted: one with non-erosive synovitis of the wrist, one with wrist synovitis with minimal erosion, and two with erosive arthritis of the distal interphalangeal joint. Conclusion: Imaging manifestations of arthritis of Behcet disease vary, and may be similar to other seronegative arthritides

  4. Risk factors for hand-wrist disorders in repetitive work

    DEFF Research Database (Denmark)

    Thomsen, J. F.; Mikkelsen, S.; Andersen, JH;

    2007-01-01

    (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders......-response pattern. Odds ratios for the risk of hand pain was 1.7 (95% CI 1.3 to 2.2) and for possible tendonitis 1.9 (95% CI 1.1 to 3.3). There was no significant interaction between the ergonomic factors. In the follow-up analyses force remained a risk factor for hand pain (OR 1.4, 95% CI 1.1 to 1.8) and for...

  5. Pseudotumoral form of soft-tissue tuberculosis of the wrist.

    Science.gov (United States)

    Sbai, Mohamed Ali; Benzarti, Sofien; Msek, Hichem; Boussen, Monia; Khorbi, Adel

    2016-03-01

    Tuberculosis is a major public health problem in developing countries. Hand and wrist is a rare localization for extra-pulmonary tuberculosis, a pseudotumoral form of soft tissue tuberculosis of the wrist is exceptional. We report the case of a 45-year-old male presenting with a painful swelling of the dorsal aspect of the right wrist evolving for six months. Clinical study was evoking a ganglion cyst of the wrist. Intraoperatively a pseudotumoral mass with rice bodies was found, suggesting tuberculous tenosynovitis. The histopathological study revealed caseating giant cell granulomas with epithelioid cells. Cultures on Löwenstein-Jensen medium detected Mycobacterium tuberculosis. Synovectomy with removal of all the rice bodies followed by anti-tuberculous chemotherapy provided uneventful recovery. PMID:26927998

  6. Longitudinal observation of pediatric hand and wrist ganglia.

    Science.gov (United States)

    Wang, A A; Hutchinson, D T

    2001-07-01

    The purpose of this study was to examine the behavior of ganglia of the hand and wrist in young children treated without surgery. Fourteen consecutive children, less than 10 years of age, who presented with cysts of the hand and wrist were followed up by a single surgeon. The average age of the patient at the time of diagnosis was 38 months (range, 2 months to 9 years 3 months). The masses included 7 retinacular cysts, 5 volar wrist ganglia, and 2 dorsal wrist ganglia. These cysts had been present for an average of 3.3 months (range, 1-12 months) before medical advice was sought. None of the cysts were painful. Follow-up averaged 33 months (range, 9-112 months), with 79% of all cysts spontaneously resolving, the majority within a year. We believe that a child presenting with a benign hand lesion characteristic of a ganglion cyst should initially be treated by observation. PMID:11466631

  7. Kinematics and Dynamics of an Asymmetrical Parallel Robotic Wrist

    DEFF Research Database (Denmark)

    Wu, Guanglei

    2014-01-01

    This paper introduces an asymmetrical parallel robotic wrist, which can generate a decoupled unlimited-torsion motion and achieve high positioning accuracy. The kinematics, dexterity, and singularities of the manipulator are investigated to visualize the performance contours of the manipulator...

  8. MRI-identified abnormalities and wrist range of motion in asymptomatic versus symptomatic computer users

    Directory of Open Access Journals (Sweden)

    Pavlosky William F

    2010-11-01

    Full Text Available Abstract Background Previous work has shown an association between restricted wrist range of motion (ROM and upper extremity musculoskeletal disorders in computer users. We compared the prevalence of MRI-identified wrist abnormalities and wrist ROM between asymptomatic and symptomatic computer users. Methods MR images at 1.5 T of both wrists were obtained from 10 asymptomatic controls (8 F, 2 M and 14 computer users (10 F, 4 M with chronic wrist pain (10 bilateral; 4 right-side. Maximum wrist range of motion in flexion and radioulnar deviation was measured with an electrogoniometer. Results Extraosseous ganglia were identified in 66.6% of asymptomatic wrists and in 75% of symptomatic wrists. Intraosseous ganglia were identified in 45.8% of asymptomatic wrists and in 75% of symptomatic wrists, and were significantly (p p Conclusions This appears to be the first MRI study of wrist abnormalities in computer users. This study demonstrates that a variety of wrist abnormalities are common in computer users and that only intraosseous ganglia prevalence and size differed between asymptomatic and symptomatic wrists. Flexion was restricted in the dominant wrist of the symptomatic group, but the correlation between wrist flexion and intraosseous ganglion burden did not reach significance. Flexion restriction may be an indicator of increased joint loading, and identifying the cause may help to guide preventive and therapeutic interventions.

  9. Methylphenidate modifies the motion of the circadian clock.

    Science.gov (United States)

    Antle, Michael C; van Diepen, Hester C; Deboer, Tom; Pedram, Pardis; Pereira, Rob Rodrigues; Meijer, Johanna H

    2012-10-01

    People with attention-deficit/hyperactivity disorder (ADHD) often experience sleep problems, and these are frequently exacerbated by the methylphenidate they take to manage their ADHD symptoms. Many of the changes to sleep are consistent with a change in the underlying circadian clock. The present study was designed to determine if methylphenidate alone could alter properties of the circadian clock. Young male mice were examined in light-dark cycles and in constant darkness and recordings were performed on behavioral activity, sleep, and electrical activity in the suprachiasmatic nucleus (SCN) of freely moving mice. Methylphenidate in the drinking water (0.08%) significantly increased activity in the mid-to-late night, and led to a delay in the onset of activity and sleep relative to the light-dark cycle. While locomotor levels returned to baseline after treatment ended, the phase angle of entrainment required at least a week to return to baseline levels. In constant darkness, the free-running period of both wheel-running and general locomotor rhythms was lengthened by methylphenidate. When the treatment ended, the free-running period either remained stable or only partially reverted to baseline levels. Methylphenidate also altered the electrical firing rate rhythms in the SCN. It induced a delay in the trough of the rhythm, an increment in rhythm amplitude, and a reduction in rhythm variability. These observations suggest that methylphenidate alters the underlying circadian clock. The observed changes are consistent with clock alterations that would promote sleep-onset insomnia. PMID:22763623

  10. Circadian regulation of human cortical excitability.

    Science.gov (United States)

    Ly, Julien Q M; Gaggioni, Giulia; Chellappa, Sarah L; Papachilleos, Soterios; Brzozowski, Alexandre; Borsu, Chloé; Rosanova, Mario; Sarasso, Simone; Middleton, Benita; Luxen, André; Archer, Simon N; Phillips, Christophe; Dijk, Derk-Jan; Maquet, Pierre; Massimini, Marcello; Vandewalle, Gilles

    2016-01-01

    Prolonged wakefulness alters cortical excitability, which is essential for proper brain function and cognition. However, besides prior wakefulness, brain function and cognition are also affected by circadian rhythmicity. Whether the regulation of cognition involves a circadian impact on cortical excitability is unknown. Here, we assessed cortical excitability from scalp electroencephalography (EEG) responses to transcranial magnetic stimulation in 22 participants during 29 h of wakefulness under constant conditions. Data reveal robust circadian dynamics of cortical excitability that are strongest in those individuals with highest endocrine markers of circadian amplitude. In addition, the time course of cortical excitability correlates with changes in EEG synchronization and cognitive performance. These results demonstrate that the crucial factor for cortical excitability, and basic brain function in general, is the balance between circadian rhythmicity and sleep need, rather than sleep homoeostasis alone. These findings have implications for clinical applications such as non-invasive brain stimulation in neurorehabilitation. PMID:27339884

  11. Potential wrist ligament injury in rescuers performing cardiopulmonary resuscitation

    OpenAIRE

    Robert Curran; Sasha Sorr; Eva Aquino

    2013-01-01

    Wrist pain in rescuers performing chest compressions as part of cardiopulmonary resuscitation has been reported anecdotally and recently in the literature. Studies have indicated that rescuers apply as much as 644 N of force to the victim′s chest with each compression, while standards require one hundred compressions per minute. Recent research suggests that forces transmitted through the rescuers′ wrists of less than 10% of those seen during the performance of chest compressions significantl...

  12. Diagnostic and therapeutic arthroscopy of the wrist: clinical experience

    OpenAIRE

    Tuzuner, Serdar; Ozdemir, Hakan; Gur, Semih

    2004-01-01

    Wrist arthroscopy can facilitate early definitive diagnosis of soft tissue, carpal bone cartilage, the triangular fibrocartilage complex and carpal ligaments injuries. Many such injuries can be treated successfully with minimally invasive arthroscopic techniques, reducing the morbidity associated with surgical exposure and permitting earlier return to work. Between November 1991 and May 1996 19 wrist arthroscopies were performed in the Department of Orthopedics and Trauma Surgery, University ...

  13. Therapeutic Approach of Wrist Ganglion Using Electroacupuncture: Two Case Reports

    OpenAIRE

    Kim, Kyoung Min; Kang, Eun Young; Lee, Sung Hoon; Jung, A Young; Nam, Doo Hyoun; Cheon, Ji Hwan

    2014-01-01

    A ganglion cyst is a relatively common benign tumor on the wrist. Conservative and surgical approaches have been used for its treatment. Various conservative treatment methods have been suggested such as reassurance, aspiration, sclerosant injection, and direct compression. But, there is no acceptable treatment of choice yet because each suggested method has a relatively high recurrence rate. We want to report two cases in which the size of the wrist ganglion was decreased by using electroacu...

  14. Clinical significance of dynamic magnetic resonance imaging in the evaluation of wrist joint in Rheumatoid arthritis

    International Nuclear Information System (INIS)

    To assess the role of contrast-enhanced dynamic Magnetic Resonance Imaging in evaluation disease activity of rheumatoid arthritis. Forty-seven wrist joints with rheumatoid arthritis were examined prospectively. Coronal images of the wrist were obtained using fat-suppression Fast multi-planar spoiled gradient recalled (FMPSPGR) acquisition in the steady state ; TR/TE 102/6.4 msec, flip angle = 60, 4 slices per sequence, FOV = 8 cm, matrix 256 X 192 at 1.5 Tesla. Scans were carried out once before and five to eight times after an intravenous Gd-DPTA injection, at 30-second-intervals. The enhancement of synovium were measured, the enhancement ratio was calculated(postcontrast SNR/precontrast SNR) and time-enhancement ratio curves were plotted. Patients were divided into three groups according to the ratio of initial to peak enhancement : less than 30% ; 30-80% more than 80%. Differences among the three groups were statistically tested using clinical indices and laboratory data as variable. Comparing one group with another, there were no significant differences in clinical indices and laboratory data except for the parameter of grip strength. Enhancement pattern measured in a single wrist joint was not comparable to a clinical index in predicting disease activity in rheumatoid arthritis

  15. Capitolunate Arthrodesis for Treatment of Scaphoid Nonunion Advanced Collapse (SNAC) Wrist Arthritis.

    Science.gov (United States)

    Hegazy, Galal

    2015-06-01

    The aim of the study was to evaluate results of capitolunate arthrodesis for the treatment of post traumatic degenerative SNAC wrist disorders. A capitolunate arthrodesis was performed on 12 patients, three women and nine men, of 44 years in average (28-66 years). Ten patients were manual workers; dominant side was involved in seven cases with no history of previous operation. Fixation of the arthrodesis was performed with headless compression screws. Patients were reviewed at 37.4 months of average follow up (range; 12-47 months). Mayo score equal to 82.8 points. Radiolunate and capitolunate angles were decreased of 6 and 8° respectively at the final follow up radiograph compared to preoperative values. The Ten manual worker patients were able to return to their previous professional activities and the other two patients were retired but they resume their sports and recreational activities. With the advent of headless compression screws the capitolunate arthrodesis gained a higher union rate, short operative time and short rehabilitation period. In the present study the capitolunate arthrodesis allowed restoring a stable functional wrist in the 12 patients reviewed. It is a satisfactory therapeutic alternative to four corners fusion for SNAC wrist with osteoarthritis. PMID:26078508

  16. Sleep disturbances and circadian CLOCK genes in borderline personality disorder

    OpenAIRE

    Fleischer, Monika; Schafer, Michael; Coogan, Andrew; Hassler, Frank; Thome, Johannes

    2012-01-01

    Borderline personality disorder (BPD) is characterised by a deep-reaching pattern of affective instability, incoherent identity, self-injury, suicide attempts, and disturbed interpersonal relations and lifestyle. The daily activities of BPD patients are often chaotic and disorganized, with patients often staying up late while sleeping during the day. These behavioural patterns suggest that altered circadian rhythms may be associated with BPD. Furthermore, BPD patients ...

  17. When the circadian clock meets the melanin pigmentary system.

    Science.gov (United States)

    Slominski, Andrzej T; Hardeland, Rüdiger; Reiter, Russel J

    2015-04-01

    Silencing of BMAL1 and PER1 stimulates melanogenic activity of follicular and epidermal melanocytes, indicating a novel role for peripheral circadian clock processes in the regulation of melanin pigmentation. Linking the expression levels of BMAL1/PER1 with changes in melanogenesis opens exciting opportunities to study the role of the local molecular clock in modulation of melanocyte functions in the hair follicle and the epidermis with attendant effects on epidermal barrier functions in general. PMID:25785947

  18. Molecular bases of circadian rhythmicity in renal physiology and pathology

    OpenAIRE

    Bonny, Olivier; Vinciguerra, Manlio; Gumz, Michelle L.; Mazzoccoli, Gianluigi

    2013-01-01

    The physiological processes that maintain body homeostasis oscillate during the day. Diurnal changes characterize kidney functions, comprising regulation of hydro-electrolytic and acid-base balance, reabsorption of small solutes and hormone production. Renal physiology is characterized by 24-h periodicity and contributes to circadian variability of blood pressure levels, related as well to nychthemeral changes of sodium sensitivity, physical activity, vascular tone, autonomic function and neu...

  19. Ultrasonographic Diagnosis of the Hand and Wrist Joint

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ik; Choi, Sang Hee [Kangnnam Sacredheart Hospital, Hallym University Medical Center, Seoul (Korea, Republic of)

    2006-12-15

    Ultrasonographic examination of the hand and wrist is simple and easy due to their superficial anatomy, and easy accessibility. Ultrasound is indicated to evaluate persistent pain and swelling when the radiographic examination is normal. Although their anatomy is simple, the pathologic conditions of the hand and wrist are quite diverse. Although plain radiographs, CT, arthrography, and MRI have traditionally been used to evaluate the hand and wrist, nowadays, ultrasound is now being ordered with increasing frequency to scan the hand and wrist as it is a cost-effective and accurate modality for the diagnosis of focal pathology in those areas. A high-frequency linear array transducer should be used to scan the upper extremity. Available transducers up to 12 MHz provide excellent resolution. Color and power Doppler images are useful in hyperemic changes and tumor vascularity. Sonographic panorama imaging also has the advantage of demonstrating the whole extension of the lesion and of enabling a dynamic study of the hand and wrist. This action during sonographic examination not only help to diagnosis to examiner to the anatomic structures, but also localize the pathologic process to a target organ. This chapter will describe the sonographic findings associated with the most common hand and wrist pathologic conditions

  20. Circadian clock manipulation for cancer prevention and control and the relief of cancer symptoms.

    Science.gov (United States)

    Hrushesky, William J M; Grutsch, James; Wood, Patricia; Yang, Xiaoming; Oh, Eun-Young; Ansell, Christine; Kidder, Stephanie; Ferrans, Carol; Quiton, Dinah Faith T; Reynolds, Justin; Du-Quiton, Jovelyn; Levin, Robert; Lis, Christopher; Braun, Donald

    2009-12-01

    Life has evolved on this planet with regular daily spans of direct solar energy availability alternating with nocturnal spans of dark. Virtually every earth-borne life form has factored this circadian pattern into its biology to ensure the temporal coordination with its resonating environment, a task essential for its individual survival and that of its species. The first whole genome inspections of mutations in human colon and breast cancer have observed specific retained clock gene mutations. Single nucleotide polymorphisms within the genes of clock, clock-controlled, and melatonin pathways have been found to confer excess cancer risk or protection from cancer. Experimental studies have shown that specific core clock genes (Per2 and Per1) are tumor suppressors because their genetic absence doubles tumor numbers, and decreasing their expression in cancer cells doubles cancer growth rate, whereas their overexpression decreases cancer growth rate and diminishes tumor numbers. Experimental interference with circadian clock function increases cancer growth rate, and clinical circadian disruption is associated with higher cancer incidence, faster cancer progression, and shorter cancer patient survival. Patients with advanced lung cancer suffering greater circadian activity/sleep cycle disruption suffer greater interference with function, greater anxiety and depression, poorer nighttime sleep, greater daytime fatigue, and poorer quality of life than comparable patients who maintain good circadian integration. We must now determine whether strategies known to help synchronize the circadian clocks of normal individuals can do so in advanced cancer patients and whether doing so allows cancer patients to feel better and/or live longer. Several academic laboratories and at least 2 large pharmaceutical firms are screening for small molecules targeting the circadian clock to stabilize its phase and enhance its amplitude and thereby consolidate and coordinate circadian

  1. Circadian Clock Genes Are Essential for Normal Adult Neurogenesis, Differentiation, and Fate Determination.

    Directory of Open Access Journals (Sweden)

    Astha Malik

    Full Text Available Adult neurogenesis creates new neurons and glia from stem cells in the human brain throughout life. It is best understood in the dentate gyrus (DG of the hippocampus and the subventricular zone (SVZ. Circadian rhythms have been identified in the hippocampus, but the role of any endogenous circadian oscillator cells in hippocampal neurogenesis and their importance in learning or memory remains unclear. Any study of stem cell regulation by intrinsic circadian timing within the DG is complicated by modulation from circadian clocks elsewhere in the brain. To examine circadian oscillators in greater isolation, neurosphere cultures were prepared from the DG of two knockout mouse lines that lack a functional circadian clock and from mPer1::luc mice to identify circadian oscillations in gene expression. Circadian mPer1 gene activity rhythms were recorded in neurospheres maintained in a culture medium that induces neurogenesis but not in one that maintains the stem cell state. Although the differentiating neural stem progenitor cells of spheres were rhythmic, evidence of any mature neurons was extremely sparse. The circadian timing signal originated in undifferentiated cells within the neurosphere. This conclusion was supported by immunocytochemistry for mPER1 protein that was localized to the inner, more stem cell-like neurosphere core. To test for effects of the circadian clock on neurogenesis, media conditions were altered to induce neurospheres from BMAL1 knockout mice to differentiate. These cultures displayed unusually high differentiation into glia rather than neurons according to GFAP and NeuN expression, respectively, and very few BetaIII tubulin-positive, immature neurons were observed. The knockout neurospheres also displayed areas visibly devoid of cells and had overall higher cell death. Neurospheres from arrhythmic mice lacking two other core clock genes, Cry1 and Cry2, showed significantly reduced growth and increased astrocyte

  2. Reduced anxiety and depression-like behaviours in the circadian period mutant mouse afterhours.

    Directory of Open Access Journals (Sweden)

    Robert Keers

    Full Text Available BACKGROUND: Disruption of the circadian rhythm is a key feature of bipolar disorder. Variation in genes encoding components of the molecular circadian clock has been associated with increased risk of the disorder in clinical populations. Similarly in animal models, disruption of the circadian clock can result in altered mood and anxiety which resemble features of human mania; including hyperactivity, reduced anxiety and reduced depression-like behaviour. One such mutant, after hours (Afh, an ENU-derived mutant with a mutation in a recently identified circadian clock gene Fbxl3, results in a disturbed (long circadian rhythm of approximately 27 hours. METHODOLOGY: Anxiety, exploratory and depression-like behaviours were evaluated in Afh mice using the open-field, elevated plus maze, light-dark box, holeboard and forced swim test. To further validate findings for human mania, polymorphisms in the human homologue of FBXL3, genotyped by three genome wide case control studies, were tested for association with bipolar disorder. PRINCIPAL FINDINGS: Afh mice showed reduced anxiety- and depression-like behaviour in all of the behavioural tests employed, and some evidence of increased locomotor activity in some tests. An analysis of three separate human data sets revealed a gene wide association between variation in FBXL3 and bipolar disorder (P = 0.009. CONCLUSIONS: Our results are consistent with previous studies of mutants with extended circadian periods and suggest that disruption of FBXL3 is associated with mania-like behaviours in both mice and humans.

  3. Distinct roles for GABA across multiple timescales in mammalian circadian timekeeping.

    Science.gov (United States)

    DeWoskin, Daniel; Myung, Jihwan; Belle, Mino D C; Piggins, Hugh D; Takumi, Toru; Forger, Daniel B

    2015-07-21

    The suprachiasmatic nuclei (SCN), the central circadian pacemakers in mammals, comprise a multiscale neuronal system that times daily events. We use recent advances in graphics processing unit computing to generate a multiscale model for the SCN that resolves cellular electrical activity down to the timescale of individual action potentials and the intracellular molecular events that generate circadian rhythms. We use the model to study the role of the neurotransmitter GABA in synchronizing circadian rhythms among individual SCN neurons, a topic of much debate in the circadian community. The model predicts that GABA signaling has two components: phasic (fast) and tonic (slow). Phasic GABA postsynaptic currents are released after action potentials, and can both increase or decrease firing rate, depending on their timing in the interspike interval, a modeling hypothesis we experimentally validate; this allows flexibility in the timing of circadian output signals. Phasic GABA, however, does not significantly affect molecular timekeeping. The tonic GABA signal is released when cells become very excited and depolarized; it changes the excitability of neurons in the network, can shift molecular rhythms, and affects SCN synchrony. We measure which neurons are excited or inhibited by GABA across the day and find GABA-excited neurons are synchronized by-and GABA-inhibited neurons repelled from-this tonic GABA signal, which modulates the synchrony in the SCN provided by other signaling molecules. Our mathematical model also provides an important tool for circadian research, and a model computational system for the many multiscale projects currently studying brain function. PMID:26130805

  4. Circadian control sheds light on fungal bioluminescence.

    Science.gov (United States)

    Oliveira, Anderson G; Stevani, Cassius V; Waldenmaier, Hans E; Viviani, Vadim; Emerson, Jillian M; Loros, Jennifer J; Dunlap, Jay C

    2015-03-30

    Bioluminescence, the creation and emission of light by organisms, affords insight into the lives of organisms doing it. Luminous living things are widespread and access diverse mechanisms to generate and control luminescence [1-5]. Among the least studied bioluminescent organisms are phylogenetically rare fungi-only 71 species, all within the ∼ 9,000 fungi of the temperate and tropical Agaricales order-are reported from among ∼ 100,000 described fungal species [6, 7]. All require oxygen [8] and energy (NADH or NADPH) for bioluminescence and are reported to emit green light (λmax 530 nm) continuously, implying a metabolic function for bioluminescence, perhaps as a byproduct of oxidative metabolism in lignin degradation. Here, however, we report that bioluminescence from the mycelium of Neonothopanus gardneri is controlled by a temperature-compensated circadian clock, the result of cycles in content/activity of the luciferase, reductase, and luciferin that comprise the luminescent system. Because regulation implies an adaptive function for bioluminescence, a controversial question for more than two millennia [8-15], we examined interactions between luminescent fungi and insects [16]. Prosthetic acrylic resin "mushrooms," internally illuminated by a green LED emitting light similar to the bioluminescence, attract staphilinid rove beetles (coleopterans), as well as hemipterans (true bugs), dipterans (flies), and hymenopterans (wasps and ants), at numbers far greater than dark control traps. Thus, circadian control may optimize energy use for when bioluminescence is most visible, attracting insects that can in turn help in spore dispersal, thereby benefitting fungi growing under the forest canopy, where wind flow is greatly reduced. PMID:25802150

  5. Circadian- and Light-Dependent Regulation of Resting Membrane Potential and Spontaneous Action Potential Firing of Drosophila Circadian Pacemaker Neurons

    OpenAIRE

    Sheeba, Vasu; Gu, Huaiyu; Sharma, Vijay K.; O'Dowd, Diane K.; Holmes, Todd C.

    2007-01-01

    The ventral lateral neurons (LNvs) of adult Drosophila brain express oscillating clock proteins and regulate circadian behavior. Whole cell current-clamp recordings of large LNvs in freshly dissected Drosophila whole brain preparations reveal two spontaneous activity patterns that correlate with two underlying patterns of oscillating membrane potential: tonic and burst firing of sodium-dependent action potentials. Resting membrane potential and spontaneous action potential firing are rapidly ...

  6. Impairment of gradual muscle adjustment during wrist circumduction in Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Carolien M Toxopeus

    Full Text Available Purposeful movements are attained by gradually adjusted activity of opposite muscles, or synergists. This requires a motor system that adequately modulates initiation and inhibition of movement and selectively activates the appropriate muscles. In patients with Parkinson's disease (PD initiation and inhibition of movements are impaired which may manifest itself in e.g. difficulty to start and stop walking. At single-joint level, impaired movement initiation is further accompanied by insufficient inhibition of antagonist muscle activity. As the motor symptoms in PD primarily result from cerebral dysfunction, quantitative investigation of gradually adjusted muscle activity during execution of purposeful movement is a first step to gain more insight in the link between impaired modulation of initiation and inhibition at the levels of (i cerebrally coded task performance and (ii final execution by the musculoskeletal system. To that end, the present study investigated changes in gradual adjustment of muscle synergists using a manipulandum that enabled standardized smooth movement by continuous wrist circumduction. Differences between PD patients (N = 15, off-medication and healthy subjects (N = 16 concerning the relation between muscle activity and movement performance in these groups were assessed using kinematic and electromyographic (EMG recordings. The variability in the extent to which a particular muscle was active during wrist circumduction--defined as muscle activity differentiation--was quantified by EMG. We demonstrated that more differentiated muscle activity indeed correlated positively with improved movement performance, i.e. higher movement speed and increased smoothness of movement. Additionally, patients employed a less differentiated muscle activity pattern than healthy subjects. These specific changes during wrist circumduction imply that patients have a decreased ability to gradually adjust muscles causing a decline in

  7. Gravitational biology and the mammalian circadian timing system.

    Science.gov (United States)

    Fuller, C A; Murakami, D M; Sulzman, F M

    1989-01-01

    Mammals have evolved under the influence of many selective pressures. Two of these pressures have been the static force of gravity and the daily variations in the environment due to the rotation of the earth. It is now clear that each of these pressures has led to specific adaptations which influence how organisms respond to changes in either gravity or daily time cues. However, several unpredicted responses to altered gravitational environments occur within the homeostatic and circadian control systems. These results may be particularly relevant to biological and medical issues related to spaceflight. This paper demonstrates that the homeostatic regulation of rat body temperature, heart rate, and activity become depressed following exposure to a 2 G hyperdynamic field, and recovers within 5-6 days. In addition, the circadian rhythms of these same variables exhibit a depression of rhythm amplitude; however, recovery required a minimum of 7 days. PMID:11537343

  8. Panic disorder and locomotor activity

    Directory of Open Access Journals (Sweden)

    Kumano Hiroaki

    2008-11-01

    Full Text Available Abstract Background Panic disorder is one of the anxiety disorders, and anxiety is associated with some locomotor activity changes such as "restlessness". However, there have been few studies on locomotor activity in panic disorder using actigraphy, although many studies on other psychiatric disorders have been reported using actigraphy. Therefore, the aim of the present study was to investigate the relationship between panic disorder and locomotor activity pattern using a wrist-worn activity monitor. In addition, an ecological momentary assessment technique was used to record panic attacks in natural settings. Methods Sixteen patients with panic disorder were asked to wear a watch-type computer as an electronic diary for recording panic attacks for two weeks. In addition, locomotor activity was measured and recorded continuously in an accelerometer equipped in the watch-type computer. Locomotor activity data were analyzed using double cosinor analysis to calculate mesor and the amplitude and acrophase of each of the circadian rhythm and 12-hour harmonic component. Correlations between panic disorder symptoms and locomotor activity were investigated. Results There were significant positive correlations between the frequency of panic attacks and mesor calculated from double cosinor analysis of locomotor activity (r = 0.55 and between HAM-A scores and mesor calculated from double cosinor analysis of locomotor activity (r = 0.62. Conclusion Panic disorder patients with more panic attacks and more anxiety have greater objectively assessed locomotor activity, which may reflect the "restlessness" of anxiety disorders.

  9. Wrist ultrasound analysis of patients with early rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    J.A. Mendonça

    2011-01-01

    Full Text Available In the present study, we evaluated 42 wrists using the semi-quantitative scales power Doppler ultrasound (PDUS and gray scale ultrasound (GSUS with scores ranging from 0 to 3 and correlated the results with clinical, laboratory and radiographic data. Twenty-one patients (17 women and 4 men with rheumatoid arthritis according to criteria of the American College of Rheumatology were enrolled in the study from September 2008 to July 2009 at Universidade Estadual de Campinas (UNICAMP. The average disease duration was 14 months. The patients were 66.6% Caucasians and 33.3% non-Caucasians, with a mean age of 42 and 41 years, respectively. A dorsal longitudinal scan was performed by ultrasound on the radiocarpal and midcarpal joints using GE LOGIQ XP-linear ultrasound and a high frequency (8-10 MHz transducer. All patients were X-rayed, and the Larsen score was determined for the joints, with grades ranging from 0 to V. This study showed significant correlations between clinical, sonographic and laboratory data: GSUS and swollen right wrist (r = 0.546, GSUS of right wrist and swelling of left wrist (r = 0.511, PDUS of right wrist and pain in left wrist (r = 0.436, PDUS of right wrist and C-reactive protein (r = 0.466. Ultrasound can be considered a useful tool in the diagnosis of synovitis in early rheumatoid arthritis mainly when the anti-cyclic citrullinated peptide and rheumatoid factor are negative, and can lead to an early change in the therapeutic decision.

  10. Circadian Rhythms in Anesthesia and Critical Care Medicine: Potential importance of circadian disruptions

    OpenAIRE

    Brainard, Jason; Gobel, Merit; Bartels, Karsten; Scott, Benjamin; Koeppen, Michael; Eckle, Tobias

    2014-01-01

    The rotation of the earth and associated alternating cycles of light and dark–the basis of our circadian rhythms–are fundamental to human biology and culture. However, it was not until 1971 that researchers first began to describe the molecular mechanisms for the circadian system. During the last few years, groundbreaking research has revealed a multitude of circadian genes affecting a variety of clinical diseases, including diabetes, obesity, sepsis, cardiac ischemia, and sudden cardiac deat...

  11. The circadian clock protein timeless regulates phagocytosis of bacteria in Drosophila.

    Directory of Open Access Journals (Sweden)

    Elizabeth F Stone

    2012-01-01

    Full Text Available Survival of bacterial infection is the result of complex host-pathogen interactions. An often-overlooked aspect of these interactions is the circadian state of the host. Previously, we demonstrated that Drosophila mutants lacking the circadian regulatory proteins Timeless (Tim and Period (Per are sensitive to infection by S. pneumoniae. Sensitivity to infection can be mediated either by changes in resistance (control of microbial load or tolerance (endurance of the pathogenic effects of infection. Here we show that Tim regulates resistance against both S. pneumoniae and S. marcescens. We set out to characterize and identify the underlying mechanism of resistance that is circadian-regulated. Using S. pneumoniae, we found that resistance oscillates daily in adult wild-type flies and that these oscillations are absent in Tim mutants. Drosophila have at least three main resistance mechanisms to kill high levels of bacteria in their hemolymph: melanization, antimicrobial peptides, and phagocytosis. We found that melanization is not circadian-regulated. We further found that basal levels of AMP gene expression exhibit time-of-day oscillations but that these are Tim-independent; moreover, infection-induced AMP gene expression is not circadian-regulated. We then show that phagocytosis is circadian-regulated. Wild-type flies exhibit up-regulated phagocytic activity at night; Tim mutants have normal phagocytic activity during the day but lack this night-time peak. Tim appears to regulate an upstream event in phagocytosis, such as bacterial recognition or activation of phagocytic hemocytes. Interestingly, inhibition of phagocytosis in wild type flies results in survival kinetics similar to Tim mutants after infection with S. pneumoniae. Taken together, these results suggest that loss of circadian oscillation of a specific immune function (phagocytosis can have significant effects on long-term survival of infection.

  12. Smooth-muscle BMAL1 participates in blood pressure circadian rhythm regulation.

    Science.gov (United States)

    Xie, Zhongwen; Su, Wen; Liu, Shu; Zhao, Guogang; Esser, Karyn; Schroder, Elizabeth A; Lefta, Mellani; Stauss, Harald M; Guo, Zhenheng; Gong, Ming Cui

    2015-01-01

    As the central pacemaker, the suprachiasmatic nucleus (SCN) has long been considered the primary regulator of blood pressure circadian rhythm; however, this dogma has been challenged by the discovery that each of the clock genes present in the SCN is also expressed and functions in peripheral tissues. The involvement and contribution of these peripheral clock genes in the circadian rhythm of blood pressure remains uncertain. Here, we demonstrate that selective deletion of the circadian clock transcriptional activator aryl hydrocarbon receptor nuclear translocator-like (Bmal1) from smooth muscle, but not from cardiomyocytes, compromised blood pressure circadian rhythm and decreased blood pressure without affecting SCN-controlled locomotor activity in murine models. In mesenteric arteries, BMAL1 bound to the promoter of and activated the transcription of Rho-kinase 2 (Rock2), and Bmal1 deletion abolished the time-of-day variations in response to agonist-induced vasoconstriction, myosin phosphorylation, and ROCK2 activation. Together, these data indicate that peripheral inputs contribute to the daily control of vasoconstriction and blood pressure and suggest that clock gene expression outside of the SCN should be further evaluated to elucidate pathogenic mechanisms of diseases involving blood pressure circadian rhythm disruption. PMID:25485682

  13. Effects of Exposure to Intermittent versus Continuous Red Light on Human Circadian Rhythms, Melatonin Suppression, and Pupillary Constriction

    OpenAIRE

    Ho Mien, Ivan; Chua, Eric Chern-Pin; Lau, Pauline; Tan, Luuan-Chin; Lee, Ivan Tian-Guang; Yeo, Sing-Chen; Tan, Sara Shuhui; Gooley, Joshua J.

    2014-01-01

    Exposure to light is a major determinant of sleep timing and hormonal rhythms. The role of retinal cones in regulating circadian physiology remains unclear, however, as most studies have used light exposures that also activate the photopigment melanopsin. Here, we tested the hypothesis that exposure to alternating red light and darkness can enhance circadian resetting responses in humans by repeatedly activating cone photoreceptors. In a between-subjects study, healthy volunteers (n = 24, 21–...

  14. Effects of Exposure to Intermittent versus Continuous Red Light on Human Circadian Rhythms, Melatonin Suppression, and Pupillary Constriction

    OpenAIRE

    Ho Mien, Ivan; Chua, Eric Chern-Pin; Lau, Pauline; Tan, Luuan-Chin; Lee, Ivan Tian-Guang; Yeo, Sing-Chen; Tan, Sara Shuhui; Gooley, Joshua J.

    2014-01-01

    Exposure to light is a major determinant of sleep timing and hormonal rhythms. The role of retinal cones in regulating circadian physiology remains unclear, however, as most studies have used light exposures that also activate the photopigment melanopsin. Here, we tested the hypothesis that exposure to alternating red light and darkness can enhance circadian resetting responses in humans by repeatedly activating cone photoreceptors. In a between-subjects study, healthy volunteers (n = 24, 21–...

  15. Solar powered wrist worn acquisition system for continuous photoplethysmogram monitoring.

    Science.gov (United States)

    Dieffenderfer, James P; Beppler, Eric; Novak, Tristan; Whitmire, Eric; Jayakumar, Rochana; Randall, Clive; Qu, Weiguo; Rajagopalan, Ramakrishnan; Bozkurt, Alper

    2014-01-01

    We present a solar-powered, wireless, wrist-worn platform for continuous monitoring of physiological and environmental parameters during the activities of daily life. In this study, we demonstrate the capability to produce photoplethysmogram (PPG) signals using this platform. To adhere to a low power budget for solar-powering, a 574 nm green light source is used where the PPG from the radial artery would be obtained with minimal signal conditioning. The system incorporates two monocrystalline solar cells to charge the onboard 20 mAh lithium polymer battery. Bluetooth Low Energy (BLE) is used to tether the device to a smartphone that makes the phone an access point to a dedicated server for long term continuous storage of data. Two power management schemes have been proposed depending on the availability of solar energy. In low light situations, if the battery is low, the device obtains a 5-second PPG waveform every minute to consume an average power of 0.57 mW. In scenarios where the battery is at a sustainable voltage, the device is set to enter its normal 30 Hz acquisition mode, consuming around 13.7 mW. We also present our efforts towards improving the charge storage capacity of our on-board super-capacitor. PMID:25570657

  16. Performance adaptive training control strategy for recovering wrist movements in stroke patients: a preliminary, feasibility study

    Directory of Open Access Journals (Sweden)

    Sandini Giulio

    2009-12-01

    Full Text Available Abstract Background In the last two decades robot training in neuromotor rehabilitation was mainly focused on shoulder-elbow movements. Few devices were designed and clinically tested for training coordinated movements of the wrist, which are crucial for achieving even the basic level of motor competence that is necessary for carrying out ADLs (activities of daily life. Moreover, most systems of robot therapy use point-to-point reaching movements which tend to emphasize the pathological tendency of stroke patients to break down goal-directed movements into a number of jerky sub-movements. For this reason we designed a wrist robot with a range of motion comparable to that of normal subjects and implemented a self-adapting training protocol for tracking smoothly moving targets in order to facilitate the emergence of smoothness in the motor control patterns and maximize the recovery of the normal RoM (range of motion of the different DoFs (degrees of Freedom. Methods The IIT-wrist robot is a 3 DoFs light exoskeleton device, with direct-drive of each DoF and a human-like range of motion for Flexion/Extension (FE, Abduction/Adduction (AA and Pronation/Supination (PS. Subjects were asked to track a variable-frequency oscillating target using only one wrist DoF at time, in such a way to carry out a progressive splinting therapy. The RoM of each DoF was angularly scanned in a staircase-like fashion, from the "easier" to the "more difficult" angular position. An Adaptive Controller evaluated online performance parameters and modulated both the assistance and the difficulty of the task in order to facilitate smoother and more precise motor command patterns. Results Three stroke subjects volunteered to participate in a preliminary test session aimed at verify the acceptability of the device and the feasibility of the designed protocol. All of them were able to perform the required task. The wrist active RoM of motion was evaluated for each patient at the

  17. SCRIPT passive orthosis: design and technical evaluation of the wrist and hand orthosis for rehabilitation training at home.

    Science.gov (United States)

    Ates, Serdar; Lobo-Prat, Joan; Lammertse, Piet; van der Kooij, Herman; Stienen, Arno H A

    2013-06-01

    In this paper, a new hand and wrist exoskeleton design, the SCRIPT Passive Orthosis (SPO), for the rehabilitation after stroke is presented. The SPO is a wrist, hand, and finger orthosis that assists individuals after stroke that suffer from impairments caused by spasticity and abnormal synergies. These impairments are characterized in the wrist and hand by excessive involuntary flexion torques that make the hand unable to be used for many activities in daily life. The SPO can passively offset these undesired torques, but it cannot actively generate or control movements. The user needs to use voluntary muscle activation to perform movements and thus needs to have some residual muscle control to successfully use the SPO. The SPO offsets the excessive internal flexion by applying external extension torques to the joints of the wrist and fingers. The SPO physically interacts with the users using the forearm shell, the hand plate and the digit caps from the Saebo Flex, but is otherwise a completely novel design. It applies the external extension torques via passive leaf springs and elastic tension cords. The amount of this support can be adjusted to provide more or less offset force to wrist, finger, or thumb extension, manually. The SPO is equipped with sensors that can give a rough estimate of the joint rotations and applied torques, sufficient to make the orthosis interact with our interactive gaming environment. Integrated inertial and gyroscopic sensors provide limited information on the user's forearm posture. The first home-based patient experiences have already let to several issues being resolved, but have also made it clear that many improvement are still to be made. PMID:24187220

  18. MDCT arthrography of the wrist: Diagnostic accuracy and indications

    Energy Technology Data Exchange (ETDEWEB)

    De Filippo, Massimo [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy)], E-mail: massimo.defilippo@unipr.it; Pogliacomi, Francesco [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Bertellini, Annalisa [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Araoz, Philip A. [Department of Radiology, Division of Biostatistics, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (United States); Averna, Raffaele; Sverzellati, Nicola; Ingegnoli, Anna [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Corradi, Maurizio; Costantino, Cosimo [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Zompatori, Maurizio [Department of Radiological and Histopathological Sciences, Policlinic S.Orsola-Malpighi, University of Bologna, Via Massarenti 9, 40138 Bologna (Italy)

    2010-04-15

    Purpose: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k = 0.96) and statistically significant (p < 0.05). Conclusions: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.

  19. MDCT arthrography of the wrist: Diagnostic accuracy and indications

    International Nuclear Information System (INIS)

    Purpose: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k = 0.96) and statistically significant (p < 0.05). Conclusions: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.

  20. Circadian Oscillations within the Hippocampus Support Hippocampus-dependent Memory Processing

    Directory of Open Access Journals (Sweden)

    Kristin Lynn Eckel-Mahan

    2012-04-01

    Full Text Available The ability to sustain memories over long periods of time, sometimes even a lifetime, is one of the most remarkable properties of the brain. Much knowledge has been gained over the past few decades regarding the molecular correlates of memory formation. Once a memory is forged, however, the molecular events that provide permanence are as of yet unclear. Studies in multiple organisms have revealed that circadian rhythmicity is important for the formation, stability, and recall of memories [1]. The neuronal events that provide this link need to be explored further. This article will discuss the findings related to the circadian regulation of memory-dependent processes in the hippocampus. Specifically, the circadian-controlled MAP kinase and cAMP signal transduction pathway plays critical roles in the consolidation of hippocampus-dependent memory. A series of studies have revealed the circadian oscillation of this pathway within the hippocampus, an activity that is absent in memory-deficient, transgenic mice lacking Ca2+-stimulated adenylyl cyclases. Interference with these oscillations proceeding the cellular memory consolidation period impairs the persistence of hippocampus-dependent memory. These data suggest that the persistence of long-term memories may depend upon reactivation of this signal transduction pathway in the hippocampus during the circadian cycle. New data reveals the dependence of hippocampal oscillation in MAPK activity on the SCN, again underscoring the importance of this region in maintaining the circadian physiology of memory. Finally, the downstream ramification of these oscillations in terms of gene expression and epigenetics should be considered, as emerging evidence is pointing strongly to a circadian link between epigenetics and long term synaptic plasticity.

  1. Light and Gravity Effects on Circadian Rhythms of Rhesus Macaques

    Science.gov (United States)

    Fuller, Charles

    1997-01-01

    Temporal integration of a biological organism's physiological, behavioral and biochemical systems depends upon its circadian timing system. The endogenous period of this timing system is typically synchronized to the 24- hour day by environmental cues. The daily alternation of light and dark has long been known as one of the most potent environmental synchronizers influencing the circadian timing system. Alterations in the lighting environment (length or intensity of light exposure) can also affect the homeostatic state of the organism. A series of experiments was performed using rhesus monkeys with the objective of defining the fundamental properties of the circadian rhythm of body temperature. Three major experiments were performed in addition to several preliminary studies. These experiments explored 1.) the response of the rhesus body temperature rhythm to varying day length and light intensity; 2.) the response of the body temperature rhythm to light exposure as a function of time of day; and 3.) the characteristics of the metabolic heat production rhythm which is responsible for the daily cycle in body temperature. Results of these three completed experiments will be reported here. In addition, preliminary experiments were also performed in social entrainment of rhesus circadian rhythms and the properties of rhesus body temperature rhythms in constant conditions, where no external time cues were provided. Four adult male rhesus monkeys served as subjects in all experiments. All experiments were performed at the California Regional Primate Research Center. Each animal was implanted with a biotelemetry unit that measured deep body temperature. All surgeries were performed by a board certified veterinary surgeon under sterile conditions. The biotelemetry implants also provided an index of activity level in each animal. For metabolic heat production measurements, oxygen consumption and carbon dioxide production were measured and the caloric equivalent of these

  2. Systemic PPARγ deletion impairs circadian rhythms of behavior and metabolism.

    Science.gov (United States)

    Yang, Guangrui; Jia, Zhanjun; Aoyagi, Toshinori; McClain, Donald; Mortensen, Richard M; Yang, Tianxin

    2012-01-01

    Compelling evidence from both human and animal studies suggests a physiological link between the circadian rhythm and metabolism but the underlying mechanism is still incompletely understood. We examined the role of PPARγ, a key regulator of energy metabolism, in the control of physiological and behavioral rhythms by analyzing two strains of whole-body PPARγ null mouse models. Systemic inactivation of PPARγ was generated constitutively by using Mox2-Cre mice (MoxCre/flox) or inducibly by using the tamoxifen system (EsrCre/flox/TM). Circadian variations in oxygen consumption, CO(2) production, food and water intake, locomotor activity, and cardiovascular parameters were all remarkably suppressed in MoxCre/flox mice. A similar phenotype was observed in EsrCre/flox/TM mice, accompanied by impaired rhythmicity of the canonical clock genes in adipose tissues and liver but not skeletal muscles or the kidney. PPARγ inactivation in isolated preadipocytes following exposure to tamoxifen led to a similar blockade of the rhythmicity of the clock gene expression. Together, these results support an essential role of PPARγ in the coordinated control of circadian clocks and metabolic pathways. PMID:22899986

  3. Effect of Chinese traditional treatment to abate the wrist joint's rigidity after Colles fracture%中医手法改善Colles骨折后腕关节僵硬的疗效观察

    Institute of Scientific and Technical Information of China (English)

    胡晓芳; 孟冬娅

    2001-01-01

    @@ Background:The wrist joint's rigidity is commonly seen in the following conditions: absence of early correct dirigation after reposition and fixation or fixation for too long time, caused patients' functional activities to be limited.

  4. Dissection of the couplings between cellular messengers and the circadian clock

    International Nuclear Information System (INIS)

    It has been known in recent years that living cells can exhibit circadian rhythms in totally different physiological processes. Intracellular messengers were demonstrated to mediate the entrained pathways linking rhythmic components between circadian clock and its output signalling. Levels of cyclic AMP and cyclic GMP in synchronized cells, and activities of the two key enzymes (AC and PDE) responsible for the cyclic AMP metabolism were measured by applying the isotopic techniques. Bimodal circadian oscillations of the messenger levels and the enzyme activities were disclosed in LD: 12, 12 cycle and constant darkness, as well as in the dividing and non-dividing cultures of the Euglena ZC mutant. Interference experiments with the enzyme activator and inhibitor such as forskolin, 8-Br-cGMP and LY 83583, and analysis of the cell division cycle (CDC) and coupling messengers suggested that the peak pulse of cyclic AMP, circadian oscillation of the AC-cAMP-PDE system and phase-dependent regulation by cyclic GMP might be important coupling factors in downstream mediation between the circadian clock and the CDC. (7 figs.)

  5. Entrainment of the Neurospora circadian clock

    NARCIS (Netherlands)

    Merrow, M; Boesl, C; Ricken, J; Messerschmitt, M; Goedel, M; Roenneberg, T

    2006-01-01

    Neurospora crassa has been systematically investigated for circadian entrainment behavior. Many aspects of synchronization can be investigated in this simple, cellular system, ranging from systematic entrainment and drivenness to masking. Clock gene expression during entrainment and entrainment with

  6. Neuroimaging, cognition, light and circadian rhythms

    OpenAIRE

    Gaggioni, Giulia; Maquet, Pierre; Schmidt, Christina, 1984-; Dijk, Derk-Jan; Vandewalle, Gilles

    2014-01-01

    In humans, sleep and wakefulness and the associated cognitive processes are regulated through interactions between sleep homeostasis and the circadian system. Chronic disruption of sleep and circadian rhythmicity is common in our society and there is a need for a better understanding of the brain mechanisms regulating sleep, wakefulness and associated cognitive processes. This review summarizes recent investigations which provide first neural correlates of the combined influence of sleep home...

  7. Neuroanatomy of the Extended Circadian Rhythm System

    OpenAIRE

    Morin, Lawrence P

    2012-01-01

    The suprachiasmatic nucleus (SCN), site of the primary clock in the circadian rhythm system, has three major afferent connections. The most important consists of a retinohypothalamic projection through which photic information, received by classical rod/cone photoreceptors and intrinsically photoreceptive retinal ganglion cells, gains access to the clock. This information influences phase and period of circadian rhythms. The two other robust afferent projections are the median raphe serotoner...

  8. Glaucoma Alters the Circadian Timing System

    OpenAIRE

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Denis, Philippe; Cooper, Howard M.

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photi...

  9. Visual impairment and circadian rhythm disorders.

    OpenAIRE

    Lockley, SW; Arendt, J; Skene, DJ

    2007-01-01

    Many aspects of human physiology and behavior are dominated by 24-hour circadian rhythms that have a major impact on our health and well-being, including the sleep-wake cycle, alertness and performance patterns, and many daily hormone profiles. These rhythms are spontaneously generated by an internal "pacemaker" in the hypothalamus, and daily light exposure to the eyes is required to keep these circadian rhythms synchronized both internally and with the external environment. Sighted individua...

  10. Circadian Gene Networks In Bone Regeneration

    OpenAIRE

    Hassan, Nathaniel

    2012-01-01

    BACKGROUND: Previous studies suggested that vitamin D played a significant role in bone regeneration, facilitating the establishment of implant osseointegration. A whole genome microarray study further suggested that the vitamin D axis might involve circadian rhythm gene expression in the bone peripheral tissue.OBJECTIVES: To identify key gene networks involved with vitamin D receptor in the bone regeneration process and to explore any correlation with circadian rhythm gene expression in bone...

  11. Evolution of circadian organization in vertebrates

    Directory of Open Access Journals (Sweden)

    M. Menaker

    1997-03-01

    Full Text Available Circadian organization means the way in which the entire circadian system above the cellular level is put together physically and the principles and rules that determine the interactions among its component parts which produce overt rhythms of physiology and behavior. Understanding this organization and its evolution is of practical importance as well as of basic interest. The first major problem that we face is the difficulty of making sense of the apparently great diversity that we observe in circadian organization of diverse vertebrates. Some of this diversity falls neatly into place along phylogenetic lines leading to firm generalizations: i in all vertebrates there is a "circadian axis" consisting of the retinas, the pineal gland and the suprachiasmatic nucleus (SCN, ii in many non-mammalian vertebrates of all classes (but not in any mammals the pineal gland is both a photoreceptor and a circadian oscillator, and iii in all non-mammalian vertebrates (but not in any mammals there are extraretinal (and extrapineal circadian photoreceptors. An interesting explanation of some of these facts, especially the differences between mammals and other vertebrates, can be constructed on the assumption that early in their evolution mammals passed through a "nocturnal bottleneck". On the other hand, a good deal of the diversity among the circadian systems of vertebrates does not fall neatly into place along phylogenetic lines. In the present review we will consider how we might better understand such "phylogenetically incoherent" diversity and what sorts of new information may help to further our understanding of the evolution of circadian organization in vertebrates

  12. Brain photoreceptor pathways contributing to circadian rhythmicity in crayfish.

    Science.gov (United States)

    Sullivan, Jeremy M; Genco, Maria C; Marlow, Elizabeth D; Benton, Jeanne L; Beltz, Barbara S; Sandeman, David C

    2009-08-01

    Freshwater crayfish have three known photoreceptive systems: the compound eyes, extraretinal brain photoreceptors, and caudal photoreceptors. The primary goal of the work described here was to explore the contribution of the brain photoreceptors to circadian locomotory activity and define some of the underlying neural pathways. Immunocytochemical studies of the brain photoreceptors in the parastacid (southern hemisphere) crayfish Cherax destructor reveal their expression of the blue light-sensitive photopigment cryptochrome and the neurotransmitter histamine. The brain photoreceptors project to two small protocerebral neuropils, the brain photoreceptor neuropils (BPNs), where they terminate among fibers expressing the neuropeptide pigment-dispersing hormone (PDH), a signaling molecule in arthropod circadian systems. Comparable pathways are also described in the astacid (northern hemisphere) crayfish Procambarus clarkii. Despite exhibiting markedly different diurnal locomotor activity rhythms, removal of the compound eyes and caudal photoreceptors in both C. destructor and P. clarkii (leaving the brain photoreceptors intact) does not abolish the normal light/dark activity cycle in either species, nor prevent the entrainment of their activity cycles to phase shifts of the light/dark period. These results suggest, therefore, that crayfish brain photoreceptors are sufficient for the entrainment of locomotor activity rhythms to photic stimuli, and that they can act in the absence of the compound eyes and caudal photoreceptors. We also demonstrate that the intensity of PDH expression in the BPNs varies in phase with the locomotor activity rhythm of both crayfish species. Together, these findings suggest that the brain photoreceptor cells can function as extraretinal circadian photoreceptors and that the BPN represents part of an entrainment pathway synchronizing locomotor activity to environmental light/dark cycles, and implicating the neuropeptide PDH in these functions

  13. Soft-tissue approach to hand and wrist trauma

    International Nuclear Information System (INIS)

    This paper provides information that will help minimize nondiagnosis of significant injuries to the hand and wrist, currently the most common cause of litigation in radiology. Soft-tissue swelling accompanies all significant injuries. The soft-tissue anatomy determines the patterns of swelling seen in acute injuries to the hand and wrist. Knowledge of the detectable patterns of swelling logically directs attention to the region of greatest trauma, minimizing the possibility that subtle sprains, fractures, and dislocations will be overlooked. Principles of joint space evaluation, alignment assessment, and additional evaluation techniques are other tools that will minimize nondiagnosis. Common examples of trauma to the hand and wrist in all age groups have been selected to illustrate the usefulness of this technique. Subtleties are stressed and unusual injuries illustrated

  14. Circadian Clock Control of Liver Metabolic Functions.

    Science.gov (United States)

    Reinke, Hans; Asher, Gad

    2016-03-01

    The circadian clock is an endogenous biological timekeeping system that synchronizes physiology and behavior to day/night cycles. A wide variety of processes throughout the entire gastrointestinal tract and notably the liver appear to be under circadian control. These include various metabolic functions such as nutrient uptake, processing, and detoxification, which align organ function to cycle with nutrient supply and demand. Remarkably, genetic or environmental disruption of the circadian clock can cause metabolic diseases or exacerbate pathological states. In addition, modern lifestyles force more and more people worldwide into asynchrony between the external time and their circadian clock, resulting in a constant state of social jetlag. Recent evidence indicates that interactions between altered energy metabolism and disruptions in the circadian clock create a downward spiral that can lead to diabetes and other metabolic diseases. In this review, we provide an overview of rhythmic processes in the liver and highlight the functions of circadian clock genes under physiological and pathological conditions; we focus on their roles in regulation of hepatic glucose as well as lipid and bile acid metabolism and detoxification and their potential effects on the development of fatty liver and nonalcoholic steatohepatitis. PMID:26657326

  15. 78 FR 68905 - Agency Information Collection (Wrist Conditions Disability Benefits Questionnaire) Under OMB Review

    Science.gov (United States)

    2013-11-15

    ... AFFAIRS Agency Information Collection (Wrist Conditions Disability Benefits Questionnaire) Under OMB... Questionnaire)'' in any correspondence. FOR FURTHER INFORMATION CONTACT: Crystal Rennie, Enterprise Records... Disability Benefits Questionnaire)''. SUPPLEMENTARY INFORMATION: Title: Wrist Conditions Disability...

  16. Circadian variation of EEG power spectra in NREM and REM sleep in humans: dissociation from body temperature

    Science.gov (United States)

    Dijk, D. J.

    1999-01-01

    In humans, EEG power spectra in REM and NREM sleep, as well as characteristics of sleep spindles such as their duration, amplitude, frequency and incidence, vary with circadian phase. Recently it has been hypothesized that circadian variations in EEG spectra in humans are caused by variations in brain or body temperature and may not represent phenomena relevant to sleep regulatory processes. To test this directly, a further analysis of EEG power spectra - collected in a forced desynchrony protocol in which sleep episodes were scheduled to a 28-h period while the rhythms of body temperature and plasma melatonin were oscillating at their near 24-h period - was carried out. EEG power spectra were computed for NREM and REM sleep occurring between 90-120 and 270-300 degrees of the circadian melatonin rhythm, i.e. just after the clearance of melatonin from plasma in the 'morning' and just after the 'evening' increase in melatonin secretion. Average body temperatures during scheduled sleep at these two circadian phases were identical (36.72 degrees C). Despite identical body temperatures, the power spectra in NREM sleep were very different at these two circadian phases. EEG activity in the low frequency spindle range was significantly and markedly enhanced after the evening increase in plasma melatonin as compared to the morning phase. For REM sleep, significant differences in power spectra during these two circadian phases, in particular in the alpha range, were also observed. The results confirm that EEG power spectra in NREM and REM sleep vary with circadian phase, suggesting that the direct contribution of temperature to the circadian variation in EEG power spectra is absent or only minor, and are at variance with the hypothesis that circadian variations in EEG power spectra are caused by variations in temperature.

  17. Qualifying CT for wrist arthroplasty: extending techniques for total hip arthroplasty to total wrist arthroplasty

    Science.gov (United States)

    Alcala, Yvonne; Olivecrona, Henrik; Olivecrona, Lotta; Noz, Marilyn E.; Maguire, Gerald Q., Jr.; Zeleznik, Michael P.; Sollerman, Christer

    2005-04-01

    The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, 1 mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

  18. Rapid Adjustment of Circadian Clocks to Simulated Travel to Time Zones across the Globe.

    Science.gov (United States)

    Harrison, Elizabeth M; Gorman, Michael R

    2015-12-01

    Daily rhythms in mammalian physiology and behavior are generated by a central pacemaker located in the hypothalamic suprachiasmatic nuclei (SCN), the timing of which is set by light from the environment. When the ambient light-dark cycle is shifted, as occurs with travel across time zones, the SCN and its output rhythms must reset or re-entrain their phases to match the new schedule-a sluggish process requiring about 1 day per hour shift. Using a global assay of circadian resetting to 6 equidistant time-zone meridians, we document this characteristically slow and distance-dependent resetting of Syrian hamsters under typical laboratory lighting conditions, which mimic summer day lengths. The circadian pacemaker, however, is additionally entrainable with respect to its waveform (i.e., the shape of the 24-h oscillation) allowing for tracking of seasonally varying day lengths. We here demonstrate an unprecedented, light exposure-based acceleration in phase resetting following 2 manipulations of circadian waveform. Adaptation of circadian waveforms to long winter nights (8 h light, 16 h dark) doubled the shift response in the first 3 days after the shift. Moreover, a bifurcated waveform induced by exposure to a novel 24-h light-dark-light-dark cycle permitted nearly instant resetting to phase shifts from 4 to 12 h in magnitude, representing a 71% reduction in the mismatch between the activity rhythm and the new photocycle. Thus, a marked enhancement of phase shifting can be induced via nonpharmacological, noninvasive manipulation of the circadian pacemaker waveform in a model species for mammalian circadian rhythmicity. Given the evidence of conserved flexibility in the human pacemaker waveform, these findings raise the promise of flexible resetting applicable to circadian disruption in shift workers, frequent time-zone travelers, and any individual forced to adjust to challenging schedules. PMID:26275871

  19. The output signal of Purkinje cells of the cerebellum and circadian rhythmicity.

    Directory of Open Access Journals (Sweden)

    Jérôme Mordel

    Full Text Available Measurement of clock gene expression has recently provided evidence that the cerebellum, like the master clock in the SCN, contains a circadian oscillator. The cerebellar oscillator is involved in anticipation of mealtime and possibly resides in Purkinje cells. However, the rhythmic gene expression is likely transduced into a circadian cerebellar output signal to exert an effective control of neuronal brain circuits that are responsible for feeding behavior. Using electrophysiological recordings from acute and organotypic cerebellar slices, we tested the hypothesis whether Purkinje cells transmit a circadian modulated signal to their targets in the brain. Extracellular recordings from brain slices revealed the typical discharge pattern previously described in vivo in single cell recordings showing basically a tonic or a trimodal-like firing pattern. However, in acute sagittal cerebellar slices the average spike rate of randomly selected Purkinje cells did not exhibit significant circadian variations, irrespective of their specific firing pattern. Also, frequency and amplitude of spontaneous inhibitory postsynaptic currents and the amplitude of GABA- and glutamate-evoked currents did not vary with circadian time. Long-term recordings using multielectrode arrays (MEA allowed to monitor neuronal activity at multiple sites in organotypic cerebellar slices for several days to weeks. With this recording technique we observed oscillations of the firing rate of cerebellar neurons, presumably of Purkinje cells, with a period of about 24 hours which were stable for periods up to three days. The daily renewal of culture medium could induce circadian oscillations of the firing rate of Purkinje cells, a feature that is compatible with the behavior of slave oscillators. However, from the present results it appears that the circadian expression of cerebellar clock genes exerts only a weak influence on the electrical output of cerebellar neurons.

  20. A novel protein, CHRONO, functions as a core component of the mammalian circadian clock.

    Directory of Open Access Journals (Sweden)

    Akihiro Goriki

    2014-04-01

    Full Text Available Circadian rhythms are controlled by a system of negative and positive genetic feedback loops composed of clock genes. Although many genes have been implicated in these feedback loops, it is unclear whether our current list of clock genes is exhaustive. We have recently identified Chrono as a robustly cycling transcript through genome-wide profiling of BMAL1 binding on the E-box. Here, we explore the role of Chrono in cellular timekeeping. Remarkably, endogenous CHRONO occupancy around E-boxes shows a circadian oscillation antiphasic to BMAL1. Overexpression of Chrono leads to suppression of BMAL1-CLOCK activity in a histone deacetylase (HDAC -dependent manner. In vivo loss-of-function studies of Chrono including Avp neuron-specific knockout (KO mice display a longer circadian period of locomotor activity. Chrono KO also alters the expression of core clock genes and impairs the response of the circadian clock to stress. CHRONO forms a complex with the glucocorticoid receptor and mediates glucocorticoid response. Our comprehensive study spotlights a previously unrecognized clock component of an unsuspected negative circadian feedback loop that is independent of another negative regulator, Cry2, and that integrates behavioral stress and epigenetic control for efficient metabolic integration of the clock.

  1. Lithium impacts on the amplitude and period of the molecular circadian clockwork.

    Directory of Open Access Journals (Sweden)

    Jian Li

    Full Text Available Lithium salt has been widely used in treatment of Bipolar Disorder, a mental disturbance associated with circadian rhythm disruptions. Lithium mildly but consistently lengthens circadian period of behavioural rhythms in multiple organisms. To systematically address the impacts of lithium on circadian pacemaking and the underlying mechanisms, we measured locomotor activity in mice in vivo following chronic lithium treatment, and also tracked clock protein dynamics (PER2::Luciferase in vitro in lithium-treated tissue slices/cells. Lithium lengthens period of both the locomotor activity rhythms, as well as the molecular oscillations in the suprachiasmatic nucleus, lung tissues and fibroblast cells. In addition, we also identified significantly elevated PER2::LUC expression and oscillation amplitude in both central and peripheral pacemakers. Elevation of PER2::LUC by lithium was not associated with changes in protein stabilities of PER2, but instead with increased transcription of Per2 gene. Although lithium and GSK3 inhibition showed opposing effects on clock period, they acted in a similar fashion to up-regulate PER2 expression and oscillation amplitude. Collectively, our data have identified a novel amplitude-enhancing effect of lithium on the PER2 protein rhythms in the central and peripheral circadian clockwork, which may involve a GSK3-mediated signalling pathway. These findings may advance our understanding of the therapeutic actions of lithium in Bipolar Disorder or other psychiatric diseases that involve circadian rhythm disruptions.

  2. Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome

    OpenAIRE

    Lisa A. Zukowski, MA; Jaimie A. Roper, MS; Orit Shechtman, PhD, OTR/L; Dana M. Otzel, PhD; Patty W. Hovis, MSESS; Mark D. Tillman, PhD

    2014-01-01

    Among conventional manual wheelchair (CMW) users, 49% to 63% experience carpal tunnel syndrome (CTS) that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM) tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury part...

  3. Quantifying forearm and wrist joint power during unconstrained movements in healthy individuals

    OpenAIRE

    Flores, Diana Castillo; Laurendeau, Simon; Teasdale, Normand; Simoneau, Martin

    2014-01-01

    Background Wrist movement-related injuries account for a large number of repetitive motion injuries. Remarkably little, if any, empirical data exist to quantify the impact of neuromuscular disorders affecting the wrist or to validate the effectiveness of rehabilitation training programs on wrist functions. The aim of this project was to develop a biomechanical model for quantifying wrist and forearm kinetics during unconstrained movements, to assess its reliability and to determine its sensit...

  4. Imaging of radial wrist pain. I. Imaging modalities and anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan Ka Lok; Griffith, James F.; Ng, Alex Wing Hung [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Hong Kong, Shatin (China); Wong, Clara Wing Yee [The Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Shatin (China)

    2014-06-15

    Radial wrist pain is a common clinical complaint. The relatively complex anatomy in this region, combined with the small size of the anatomical structures and occasionally subtle imaging findings, can pose problems when trying to localize the exact cause of pain. To fully comprehend the underlying pathology, one needs a good understanding of both radial-sided wrist anatomy and the relative merits of the different imaging techniques used to assess these structures. In part I of this review, these aspects will be discussed. (orig.)

  5. Ulnar-sided wrist pain. II. Clinical imaging and treatment

    International Nuclear Information System (INIS)

    Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed. (orig.)

  6. Ulnar-sided wrist pain. II. Clinical imaging and treatment

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Atsuya; Souza, Felipe [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Vezeridis, Peter S.; Blazar, Philip [Brigham and Women' s Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Yoshioka, Hiroshi [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); University of California-Irvine, Department of Radiological Sciences, Irvine, CA (United States); UC Irvine Medical Center, Department of Radiological Sciences, Orange, CA (United States)

    2010-09-15

    Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed. (orig.)

  7. Anthropometric characteristics of wrists joint surfaces depending on lunate types.

    Science.gov (United States)

    Dyankova, S

    2007-10-01

    It is well known that the lunate presents with two main types: lunate type I has one facet of its distal surface only for capitates, whereas lunate type II has two facets of the same surface for capitate and for hamate. Our previous anthropometric studies showed that the lunate type II wrists are of greater size than the lunate type I wrists. The aim of the present study was to determine whether the lunate types and the presence or absence of hamato-lunate joint correlate with anthropometric characteristics of the joint surfaces of other wrists. Sixteen sets of macerated wrists with the lunate type I and 21 with the lunate type II were studied. Two-thousand-four-hundred-and-forty-eight anthropometric measurements were done (for 68 anthropometric indicators) and 864 anthropometric indices were calculated (for 24 anthropometric indices) separately for the wrist joint surfaces. The absolute value of the anthropometric indicators of the joint surfaces of the separated wrists were greater in the wrists with the lunate type II, except for the indicators "Greatest length of the dorsal joint surface of pisiform", "Width of the proximal joint surface, measured in the middle" and "Greatest width of the proximal joint surface" for the trapezoid and "Greatest height of the ulnar joint surface" for the capitate. The enlargement of the joint surfaces for the scaphoid was mainly in proximo-distal direction. The enlargement for the triquetrum and pisiform was mainly in radio-ulnar direction. The enlargement for trapezium, trapezoid and capitate was mainly in dorso-volar direction (except for the ulnar joint surface of capitate). The enlargement for hamate was mainly in radio-ulnar and dorso-volar directions (except for the joint surfaces for capitate and triquetrum). The calculated indices illustrate the quantitative proportions of the variations mentioned above. The anthropometric differences are a good reason to make a clear distinction between both types of wrist joint

  8. Potential wrist ligament injury in rescuers performing cardiopulmonary resuscitation

    Directory of Open Access Journals (Sweden)

    Robert Curran

    2013-01-01

    Full Text Available Wrist pain in rescuers performing chest compressions as part of cardiopulmonary resuscitation has been reported anecdotally and recently in the literature. Studies have indicated that rescuers apply as much as 644 N of force to the victim′s chest with each compression, while standards require one hundred compressions per minute. Recent research suggests that forces transmitted through the rescuers′ wrists of less than 10% of those seen during the performance of chest compressions significantly strain the scapholunate ligament. Biomechanical research should be performed to further evaluate this possible correlation. Compensation for worker injury maybe involved.

  9. Imaging of radial wrist pain. I. Imaging modalities and anatomy

    International Nuclear Information System (INIS)

    Radial wrist pain is a common clinical complaint. The relatively complex anatomy in this region, combined with the small size of the anatomical structures and occasionally subtle imaging findings, can pose problems when trying to localize the exact cause of pain. To fully comprehend the underlying pathology, one needs a good understanding of both radial-sided wrist anatomy and the relative merits of the different imaging techniques used to assess these structures. In part I of this review, these aspects will be discussed. (orig.)

  10. Radiographic findings in wrists and hands of patients with leprosy

    International Nuclear Information System (INIS)

    Leprosy, like other neuropathic disorders, can involve the skeleton, affecting both bone and joints, especially those segments that have to withstand weight. To asses the osteoarticular involvement of the wrist and hand in 58 patients with leprosy. The radiographic images of wrist and hand of 58 patients with Hansen's disease were reviewed. The entire spectrum of specific and nonspecific bone lesions described in the literature is presented. Despite the fact that the upper limbs do not have to withstand the weight that the feet and ankles do, radiographic images show that gripping and other common motions can also produce lesions compatible with those of neuropathic arthropathy. (Author) 20 refs

  11. Circadian rhythm in plasma concentrations of gamma-hydroxybutyric acid in alcoholics.

    Science.gov (United States)

    Hoes, M J; Vree, T B; Guelen, P J

    1981-08-01

    Gamma-hydroxybutyric acid (GHB) was orally administered to six alcoholics at 09.00 and 23.00 h. The plasma concentrations of GHB show a clear circadian pattern, the area under the curve in the daytime experiments being 61% of that in the night experiments. The significance of alcohol dehydrogenase, the catabolic enzyme of GHB, for the difference is discussed. It is concluded that, although the activity of alcohol dehydrogenase in alcoholics is quantitatively disturbed, it remains subject to physiologic circadian activation. PMID:7341501

  12. 21 CFR 888.3800 - Wrist joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3800 Section 888.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Wrist joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A wrist joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a wrist...

  13. Synchronization of circadian Per2 rhythms and HSF1-BMAL1:CLOCK interaction in mouse fibroblasts after short-term heat shock pulse.

    Directory of Open Access Journals (Sweden)

    Teruya Tamaru

    Full Text Available Circadian rhythms are the general physiological processes of adaptation to daily environmental changes, such as the temperature cycle. A change in temperature is a resetting cue for mammalian circadian oscillators, which are possibly regulated by the heat shock (HS pathway. The HS response (HSR is a universal process that provides protection against stressful conditions, which promote protein-denaturation. Heat shock factor 1 (HSF1 is essential for HSR. In the study presented here, we investigated whether a short-term HS pulse can reset circadian rhythms. Circadian Per2 rhythm and HSF1-mediated gene expression were monitored by a real-time bioluminescence assay for mPer2 promoter-driven luciferase and HS element (HSE; HSF1-binding site-driven luciferase activity, respectively. By an optimal duration HS pulse (43°C for approximately 30 minutes, circadian Per2 rhythm was observed in the whole mouse fibroblast culture, probably indicating the synchronization of the phases of each cell. This rhythm was preceded by an acute elevation in mPer2 and HSF1-mediated gene expression. Mutations in the two predicted HSE sites adjacent (one of them proximally to the E-box in the mPer2 promoter dramatically abolished circadian mPer2 rhythm. Circadian Per2 gene/protein expression was not observed in HSF1-deficient cells. These findings demonstrate that HSF1 is essential to the synchronization of circadian rhythms by the HS pulse. Importantly, the interaction between HSF1 and BMAL1:CLOCK heterodimer, a central circadian transcription factor, was observed after the HS pulse. These findings reveal that even a short-term HS pulse can reset circadian rhythms and cause the HSF1-BMAL1:CLOCK interaction, suggesting the pivotal role of crosstalk between the mammalian circadian and HSR systems.

  14. Intra-articular distribution pattern after ultrasound-guided injections in wrist joints of patients with rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Boesen, Mikael [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)], E-mail: parker@frh.regioh.dk; Jensen, Karl Erik [State Hospital, Department of Radiology, MRI Division, Copenhagen (Denmark)], E-mail: karl.erik.Jensen@rh.regionh.dk; Torp-Pedersen, Soren [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark); Cimmino, Marco A. [Rheumatologic Clinic, Department of Internal Medicine, University of Genoa (Italy)], E-mail: cimmino@unige.it; Danneskiold-Samsoe, Bente; Bliddal, Henning [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)

    2009-02-15

    Objective: To investigate the distribution of an ultrasound-guided intra-articular (IA) injection in the wrist joint of patients with rheumatoid arthritis (RA). Methods: An ultrasound-guided IA drug injection into the wrist joint was performed in 17 patients with 1 ml methylprednisolone (40 mg/ml), 0.5 ml Lidocaine (5 mg/ml) and 0.15 ml gadolinium (Omniscan 0.5 mmol/ml). The drug solution was placed in the central proximal part of the wrist between the distal radius and the lunate bone. Coronal and axial MRI sequences were performed after the injection to visualize the distribution. Carpal distribution (radio-carpal, inter-carpal, and carpo-metacarpal) as well as radio-ulnar distribution was recorded. Full distribution in one compartment was given the value 1, partial distribution 0.5 and no distribution 0. A sum of the total distribution for all four compartments was calculated and correlated to the clinical parameters and the MRI OMERACT scores. Results: No uniform pattern was seen in the distribution of the contrast. Only two patients had full contrast distribution to all four compartments, and the mean distribution count for all patients was 2.4 (range 0.5-4). The distribution count correlated with the MRI OMERACT synovitis score (r = 0.60, p = 0.014), but not with the erosions, bonemarrow oedema scores or any clinical parameters. Conclusion: The distribution of contrast on MRI showed patient specific and random patterns after IA injections in active RA wrist joints. The degree of distribution increased with the MRI synovitis score, while no association was found with the erosion- and bonemarrow oedema score. These results indicate that a single injection into a standard injection site in the proximal part of the wrist cannot be assumed to distribute - and treat - the whole joint.

  15. Using Actiwatch to monitor circadian rhythm disturbance in Huntington' disease: A cautionary note.

    Science.gov (United States)

    Townhill, Jenny; Hughes, Alis C; Thomas, Benny; Busse, Monica E; Price, Kathy; Dunnett, Stephen B; Hastings, Michael H; Rosser, Anne E

    2016-05-30

    Huntington's disease (HD) is an inherited neurodegenerative disorder that is well recognised as producing progressive deterioration of motor function, including dyskinetic movements, as well as deterioration of cognition and ability to carry out activities of daily living. However, individuals with HD commonly suffer from a wide range of additional symptoms, including weight loss and sleep disturbance, possibly due to disruption of circadian rhythmicity. Disrupted circadian rhythms have been reported in mice models of HD and in humans with HD. One way of assessing an individual's circadian rhythmicity in a community setting is to monitor their sleep/wake cycles, and a convenient method for recording periods of wakefulness and sleep is to use accelerometers to discriminate between varied activity levels (including sleep) during daily life. Here we used Actiwatch(®) Activity monitors alongside ambulatory EEG and sleep diaries to record wake/sleep patterns in people with HD and normal volunteers. We report that periods of wakefulness during the night, as detected by activity monitors, agreed poorly with EEG recordings in HD subjects, and unsurprisingly sleep diary findings showed poor agreement with both EEG recordings and activity monitor derived sleep periods. One explanation for this is the occurrence of 'break through' involuntary movements during sleep in the HD patients, which are incorrectly assessed as wakeful periods by the activity monitor algorithms. Thus, care needs to be taken when using activity monitors to assess circadian activity in individuals with movement disorders. PMID:26774754

  16. Circadian rhythmicity of synapses in mouse somatosensory cortex.

    Science.gov (United States)

    Jasinska, Malgorzata; Grzegorczyk, Anna; Woznicka, Olga; Jasek, Ewa; Kossut, Malgorzata; Barbacka-Surowiak, Grazyna; Litwin, Jan A; Pyza, Elzbieta

    2015-10-01

    The circadian rhythmicity displayed by motor behavior of mice: activity at night and rest during the day; and the associated changes in the sensory input are reflected by cyclic synaptic plasticity in the whisker representations located in the somatosensory (barrel) cortex. It was not clear whether diurnal rhythmic changes in synapse density previously observed in the barrel cortex resulted from changes in the activity of the animals, from daily light/dark (LD) rhythm or are driven by an endogenous clock. These changes were investigated in the barrel cortex of C57BL/6 mouse strain kept under LD 12 : 12 h conditions and in constant darkness (DD). Stereological analysis of serial electron microscopic sections was used to assess numerical density of synapses. In mice kept under LD conditions, the total density of synapses and the density of excitatory synapses located on dendritic spines was higher during the light period (rest phase). In contrast, the density of inhibitory synapses located on dendritic spines increased during the dark period (activity phase). Under DD conditions, the upregulation of the inhibitory synapses during the activity phase was retained, but the cyclic changes in the density of excitatory synapses were not observed. The results show that the circadian plasticity concerns only synapses located on spines (and not those on dendritic shafts), and that excitatory and inhibitory synapses are differently regulated during the 24 h cycle: the excitatory synapses are influenced by light, whilst the inhibitory synapses are driven by the endogenous circadian clock. PMID:26274013

  17. Effects of (± 3,4-Methylenedioxymethamphetamine (MDMA on Sleep and Circadian Rhythms

    Directory of Open Access Journals (Sweden)

    Una D. McCann

    2007-01-01

    Full Text Available Abuse of stimulant drugs invariably leads to a disruption in sleep-wake patterns by virtue of the arousing and sleep-preventing effects of these drugs. Certain stimulants, such as 3,4-methylenedioxymethamphetamine (MDMA, may also have the potential to produce persistent alterations in circadian regulation and sleep because they can be neurotoxic toward brain monoaminergic neurons involved in normal sleep regulation. In particular, MDMA has been found to damage brain serotonin (5-HT neurons in a variety of animal species, including nonhuman primates, with growing evidence that humans are also susceptible to MDMA-induced brain 5-HT neurotoxicity. 5-HT is an important modulator of sleep and circadian rhythms and, therefore, individuals who sustain MDMA-induced 5-HT neurotoxicity may be at risk for developing chronic abnormalities in sleep and circadian patterns. In turn, such abnormalities could play a significant role in other alterations reported in abstinent in MDMA users (e.g., memory disturbance. This paper will review preclinical and clinical studies that have explored the effects of prior MDMA exposure on sleep, circadian activity, and the circadian pacemaker, and will highlight current gaps in knowledge and suggest areas for future research.

  18. Ketamine influences CLOCK:BMAL1 function leading to altered circadian gene expression.

    Directory of Open Access Journals (Sweden)

    Marina M Bellet

    Full Text Available Major mood disorders have been linked to abnormalities in circadian rhythms, leading to disturbances in sleep, mood, temperature, and hormonal levels. We provide evidence that ketamine, a drug with rapid antidepressant effects, influences the function of the circadian molecular machinery. Ketamine modulates CLOCK:BMAL1-mediated transcriptional activation when these regulators are ectopically expressed in NG108-15 neuronal cells. Inhibition occurs in a dose-dependent manner and is attenuated after treatment with the GSK3β antagonist SB21673. We analyzed the effect of ketamine on circadian gene expression and observed a dose-dependent reduction in the amplitude of circadian transcription of the Bmal1, Per2, and Cry1 genes. Finally, chromatin-immunoprecipitation analyses revealed that ketamine altered the recruitment of the CLOCK:BMAL1 complex on circadian promoters in a time-dependent manner. Our results reveal a yet unsuspected molecular mode of action of ketamine and thereby may suggest possible pharmacological antidepressant strategies.

  19. Acidic digestion in a teleost: postprandial and circadian pattern of gastric pH, pepsin activity, and pepsinogen and proton pump mRNAs expression.

    Directory of Open Access Journals (Sweden)

    Manuel Yúfera

    Full Text Available Two different modes for regulation of stomach acid secretion have been described in vertebrates. Some species exhibit a continuous acid secretion maintaining a low gastric pH during fasting. Others, as some teleosts, maintain a neutral gastric pH during fasting while the hydrochloric acid is released only after the ingestion of a meal. Those different patterns seem to be closely related to specific feeding habits. However, our recent observations suggest that this acidification pattern could be modified by changes in daily feeding frequency and time schedule. The aim of this study was to advance in understanding the regulation mechanisms of stomach digestion and pattern of acid secretion in teleost fish. We have examined the postprandial pattern of gastric pH, pepsin activity, and mRNA expression for pepsinogen and proton pump in white seabream juveniles maintained under a light/dark 12/12 hours cycle and receiving only one morning meal. The pepsin activity was analyzed according to the standard protocol buffering at pH 2 and using the actual pH measured in the stomach. The results show how the enzyme precursor is permanently available while the hydrochloric acid, which activates the zymogen fraction, is secreted just after the ingestion of food. Results also reveal that analytical protocol at pH 2 notably overestimates true pepsin activity in fish stomach. The expression of the mRNA encoding pepsinogen and proton pump exhibited almost parallel patterns, with notable increases during the darkness period and sharp decreases just before the morning meal. These results indicate that white seabream uses the resting hours for recovering the mRNA stock that will be quickly used during the feeding process. Our data clearly shows that both daily illumination pattern and feeding time are involved at different level in the regulation of the secretion of digestive juices.

  20. Timed food availability affects circadian behavior but not the neuropeptide Y expression in Indian weaverbirds exposed to atypical light environment.

    Science.gov (United States)

    Singh, Devraj; Trivedi, Neerja; Malik, Shalie; Rani, Sangeeta; Kumar, Vinod

    2016-07-01

    We tested the hypothesis whether daily food availability period would restore rhythmicity in individuals with disrupted circadian behavior with no effect on appetite regulation. Particularly, we investigated the effects of timed food availability on activity behavior, and Fos and neuropeptide Y expressions in Indian weaverbirds (Ploceus philippinus) under atypical light conditions. Initially, weaverbirds in 3 groups of 7-8 each were entrained to 7L:17D (25: hypothalamus and infundibular nuclear complex. Another identical experiment examined after-effects of the 3 light conditions on persistence of the circadian rhythms. Weaverbirds exposed for 4weeks to identical food but different light conditions, as above, were released into the free-running condition of food ad libitum and LLdim. Circadian rhythms were decayed in birds previously exposed to T7 LD cycle. Overall, these results show that timed meal restores rhythmicity in individuals with circadian rhythm disruptions without involving neuropeptide Y, the key appetite regulatory molecule. PMID:27085910

  1. Statistical Modeling of Shape and Motion of the Wrist Bones

    NARCIS (Netherlands)

    Van de Giessen, M.

    2011-01-01

    Carpal instability occurs when the wrist bones assume a pathological posture, e.g. due to ligament rupture as a result of trauma. Ligament rupture cannot be diagnosed reliably directly, as current medical imaging modalities do not provide sufficient soft-tissue contrast (X-ray, CT) or lack a suffici

  2. Melanopsin resets circadian rhythms in cells by inducing clock gene Period1

    Science.gov (United States)

    Yamashita, Shuhei; Uehara, Tomoe; Matsuo, Minako; Kikuchi, Yo; Numano, Rika

    2014-02-01

    The biochemical, physiological and behavioral processes are under the control of internal clocks with the period of approximately 24 hr, circadian rhythms. The expression of clock gene Period1 (Per1) oscillates autonomously in cells and is induced immediately after a light pulse. Per1 is an indispensable member of the central clock system to maintain the autonomous oscillator and synchronize environmental light cycle. Per1 expression could be detected by Per1∷luc and Per1∷GFP plasmid DNA in which firefly luciferase and Green Fluorescence Protein were rhythmically expressed under the control of the mouse Per1 promoter in order to monitor mammalian circadian rhythms. Membrane protein, MELANOPSIN is activated by blue light in the morning on the retina and lead to signals transduction to induce Per1 expression and to reset the phase of circadian rhythms. In this report Per1 induction was measured by reporter signal assay in Per1∷luc and Per1∷GFP fibroblast cell at the input process of circadian rhythms. To the result all process to reset the rhythms by Melanopsin is completed in single cell like in the retina projected to the central clock in the brain. Moreover, the phase of circadian rhythm in Per1∷luc cells is synchronized by photo-activated Melanopsin, because the definite peak of luciferase activity in one dish was found one day after light illumination. That is an available means that physiological circadian rhythms could be real-time monitor as calculable reporter (bioluminescent and fluorescent) chronological signal in both single and groups of cells.

  3. Simplified approach to MR image quantification of the rheumatoid wrist: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Kamishima, Tamotsu; Terae, Satoshi; Shirato, Hiroki [Hokkaido University Hospital, Department of Radiology, Sapporo City (Japan); Tanimura, Kazuhide; Aoki, Yuko; Shimizu, Masato; Matsuhashi, Megumi; Fukae, Jun [Hokkaido Medical Center for Rheumatic Diseases, Sapporo City, Hokkaido (Japan); Kosaka, Naoki [Tokeidai Memorial Hospital, Sapporo City, Hokkaido (Japan); Kon, Yujiro [St. Thomas' Hospital, Lupus Research Unit, The Rayne Institute, London (United Kingdom)

    2011-01-15

    To determine an optimal threshold in a simplified 3D-based volumetry of abnormal signals in rheumatoid wrists utilizing contrast and non-contrast MR data, and investigate the feasibility and reliability of this method. MR images of bilateral hands of 15 active rheumatoid patients were assessed before and 5 months after the initiation of tocilizumab infusion protocol. The volumes of abnormal signals were measured on STIR and post-contrast fat-suppressed T1-weighted images. Three-dimensional volume rendering of the images was used for segmentation of the wrist by an MR technologist and a radiologist. Volumetric data were obtained with variable thresholding (1, 1.25, 1.5, 1.75, and 2 times the muscle signal), and were compared to clinical data and semiquantitative MR scoring (RAMRIS) of the wrist. Intra- and interobserver variability and time needed for volumetry measurements were assessed. The volumetric data correlated favorably with clinical parameters almost throughout the pre-determined thresholds. Interval differences in volumetric data correlated favorably with those of RAMRIS when the threshold was set at more than 1.5 times the muscle signal. The repeatability index was lower than the average of the interval differences in volumetric data when the threshold was set at 1.5-1.75 for STIR data. Intra- and interobserver variability for volumetry was 0.79-0.84. The time required for volumetry was shorter than that for RAMRIS. These results suggest that a simplified MR volumetric data acquisition may provide gross estimates of disease activity when the threshold is set properly. Such estimation can be achieved quickly by non-imaging specialists and without contrast administration. (orig.)

  4. Management of the spastic wrist and hand in cerebral palsy.

    Science.gov (United States)

    Leafblad, Nels D; Van Heest, Ann E

    2015-05-01

    Research from the last 5 years on the pathophysiology and treatment of upper extremity sequelae of cerebral palsy (CP) is presented. The development of new treatments of CP-affected limbs, utilizing the brain's inherent neuroplasticity, remains an area of promising and active research. Functional magnetic resonance imaging scans have evaluated the role of neuroplasticity in adapting to the initial central nervous system insult. Children with CP appear to have greater recruitment of the ipsilateral brain for motor and sensory functions of the affected upper limb. Studies have also shown that constraint-induced movement therapy results in localized increase in gray matter volume of the sensorimotor cortex contralateral to the affected arm targeted during rehabilitation. Recent therapy interventions have emphasized the role of home therapy programs, the transient effects of splinting, and the promise of constraint-induced movement therapy and bimanual hand training. The use of motion laboratory analysis to characterize the movement pattern disturbances in children with CP continues to expand. Classification systems for CP upper limb continue to expand and improve their reliability, including use of the House Classification, the Manual Ability Classification System, and the Shriner's Hospital Upper Extremity Evaluation. Surgical outcomes have greater patients' satisfaction when they address functional limitations, also in addition to aesthetics, which may improve patients' self-esteem. Surgical techniques for elbow, wrist, fingers, and thumb continue to be refined. Research into each of these areas continues to expand our understanding of the nervous system insults that cause CP, how they may be modified, and how hand surgeons can continue to serve patients by improving their upper limb function and aesthetics. PMID:25841769

  5. Comparison between circadian motor activity in pony and horse Comparación de la actividad motora circadiano en ponis y caballos

    Directory of Open Access Journals (Sweden)

    GIUSEPPE PICCIONE

    2011-06-01

    Full Text Available In this study we investigated the influence of body mass on the daily rhythm of total motor activity in ponies and horses. Six clinically healthy Shetland pony breed with a body mass of 180 ± 30 kg and six healthy horses Sella Italiana breed with a body mass of 530 ± 20 kg were used. Animals were equipped with actigraphy-based data loggers, Actiwatch-Mini® to record total activity. The application of two-way ANOVA showed a highly significant effect of time of day and body mass on motor activity. Cosinor analysis identified the periodic parameters and their acrophases during the two days of monitoring. Mesor and amplitude were statistically higher in horses than in ponies and no statistically significant differences was found about acrophases and robustness. In conclusion we suppose that the difference in the amount of total motor activity, in animals that differ in breed, as pony and horse, may lie in physical differences.En este estudio hemos investigado la influencia de la masa corporal con respecto al ritmo circadiano de toda la actividad motora en los ponis y los caballos. Han sido utilizados seis sanos Shetland poni con una masa corporal de 180 ± 30 kg y seis sanos caballos biotipo Sella Italiana con una masa corporal de 530 ± 20 kg clínicamente sanos. Los animales han sido equipados con registrador de datos Actiwatch-Mini® para grabar toda la actividad motora. La aplicación de ANOVA dos vías mostró un efecto altamente significante de la hora del día y de la masa corporal sobre la actividad motora. El análisis del Cosinor ha identificado los parámetros periódicos y ellos acrofases en los dos días de seguimiento. Mesor y amplitud fueron estadísticamente más alto en los caballos que en los ponis y ninguna significativa diferencia estadística se encontró sobre las acrofases y robustez. En conclusión suponemos que las diferencias sobre la cantidad de toda la actividad motora en animales de diferente biotipo, como poni y

  6. Molecular Mechanisms of Circadian Regulation During Spaceflight

    Science.gov (United States)

    Zanello, Susana; Boyle, Richard

    2011-01-01

    Disruption of the regular environmental circadian cues in addition to stringent and demanding operational schedules are two main factors that undoubtedly impact sleep patterns and vigilant performance in the astronaut crews during spaceflight. Most research is focused on the behavioral aspects of the risk of circadian desynchronization, characterized by fatigue and health and performance decrement. A common countermeasure for circadian re-entrainment utilizes blue-green light to entrain the circadian clock and mitigate this risk. However, an effective countermeasure targeting the photoreceptor system requires that the basic circadian molecular machinery remains intact during spaceflight. The molecular clock consists of sets of proteins that perform different functions within the clock machinery: circadian oscillators (genes whose expression levels cycle during the day, keep the pass of cellular time and regulate downstream effector genes), the effector or output genes (those which impact the physiology of the tissue or organism), and the input genes (responsible for sensing the environmental cues that allow circadian entrainment). The main environmental cue is light. As opposed to the known photoreceptors (rods and cones), the non-visual light stimulus is received by a subset of the population of retinal ganglion cells called intrinsically photosensitive retinal ganglion cells (ipRGC) that express melanopsin (opsin 4 -Opn4-) as the photoreceptor. We hypothesize that spaceflight may affect ipRGC and melanopsin expression, which may be a contributing cause of circadian disruption during spaceflight. To answer this question, eyes from albino Balb/cJ mice aboard STS-133 were collected for histological analysis and gene expression profiling of the retina at 1 and 7 days after landing. Both vivarium and AEM (animal enclosure module) mice were used as ground controls. Opn4 expression was analyzed by real time RT/qPCR and retinal sections were stained for Opn4

  7. Natural selection against a circadian clock gene mutation in mice

    NARCIS (Netherlands)

    Spoelstra, K.; Wikelski, Martin; Daan, Serge; Loudon, Andrew; Hau, Michaela

    2015-01-01

    Circadian rhythms with an endogenous period close or equal to the natural light-dark cycle are considered evolutionarily adaptive (‘circadian resonance hypothesis’). Despite remarkable insight into the molecular mechanisms driving circadian cycles, this hypothesis has not been tested under natural c

  8. Circadian rhythms and addiction: Mechanistic insights and future directions

    OpenAIRE

    Logan, Ryan W.; Williams, Wilbur P.; McClung, Colleen A.

    2014-01-01

    Circadian rhythms are prominent in many physiological and behavioral functions. Circadian disruptions either by environmental or molecular perturbation can have profound health consequences, including the development and progression of addiction. Both animal and humans studies indicate extensive bidirectional relationships between the circadian system and drugs of abuse. Addicted individuals display disrupted rhythms, and chronic disruption or particular chronotypes, may increase the risk for...

  9. The circadian clock in cancer development and therapy

    Science.gov (United States)

    Most aspects of mammalian function display circadian rhythms driven by an endogenous clock. The circadian clock is operated by genes and comprises a central clock in the brain that responds to environmental cues and controls subordinate clocks in peripheral tissues via circadian output pathways. The...

  10. Phase resetting of the mammalian circadian clock by DNA damage

    NARCIS (Netherlands)

    Oklejewicz, Malgorzata; Destici, Eugin; Tamanini, Filippo; Hut, Roelof A.; Janssens, Roel; van der Horst, Gijsbertus T. J.

    2008-01-01

    To anticipate the momentum of the day, most organisms have developed an internal clock that drives circadian rhythms in metabolism, physiology, and behavior [1]. Recent studies indicate that cell-cycle progression and DNA-damage-response pathways are under circadian control [2-4]. Because circadian

  11. Circadian and wakefulness-sleep modulation of cognition in humans.

    Science.gov (United States)

    Wright, Kenneth P; Lowry, Christopher A; Lebourgeois, Monique K

    2012-01-01

    Cognitive and affective processes vary over the course of the 24 h day. Time of day dependent changes in human cognition are modulated by an internal circadian timekeeping system with a near-24 h period. The human circadian timekeeping system interacts with sleep-wakefulness regulatory processes to modulate brain arousal, neurocognitive and affective function. Brain arousal is regulated by ascending brain stem, basal forebrain (BF) and hypothalamic arousal systems and inhibition or disruption of these systems reduces brain arousal, impairs cognition, and promotes sleep. The internal circadian timekeeping system modulates cognition and affective function by projections from the master circadian clock, located in the hypothalamic suprachiasmatic nuclei (SCN), to arousal and sleep systems and via clock gene oscillations in brain tissues. Understanding the basic principles of circadian and wakefulness-sleep physiology can help to recognize how the circadian system modulates human cognition and influences learning, memory and emotion. Developmental changes in sleep and circadian processes and circadian misalignment in circadian rhythm sleep disorders have important implications for learning, memory and emotion. Overall, when wakefulness occurs at appropriate internal biological times, circadian clockwork benefits human cognitive and emotion function throughout the lifespan. Yet, when wakefulness occurs at inappropriate biological times because of environmental pressures (e.g., early school start times, long work hours that include work at night, shift work, jet lag) or because of circadian rhythm sleep disorders, the resulting misalignment between circadian and wakefulness-sleep physiology leads to impaired cognitive performance, learning, emotion, and safety. PMID:22529774

  12. Circadian and Wakefulness-Sleep Modulation of Cognition in Humans

    Directory of Open Access Journals (Sweden)

    Kenneth P Wright

    2012-04-01

    Full Text Available Cognitive and affective processes vary over the course of the 24 hour day. Time of day dependent changes in human cognition are modulated by an internal circadian timekeeping system with a near-24-hour period. The human circadian timekeeping system interacts with sleep-wakefulness regulatory processes to modulate brain arousal, neurocognitive and affective function. Brain arousal is regulated by ascending brain stem, basal forebrain and hypothalamic arousal systems and inhibition or disruption of these systems reduces brain arousal, impairs cognition, and promotes sleep. The internal circadian timekeeping system modulates cognition and affective function by projections from the master circadian clock, located in the hypothalamic suprachiasmatic nuclei, to arousal and sleep systems and via clock gene oscillations in brain tissues. Understanding the basic principles of circadian and wakefulness-sleep physiology can help to recognize how the circadian system modulates human cognition and influences learning, memory and emotion. Developmental changes in sleep and circadian processes and circadian misalignment in circadian rhythm sleep disorders have important implications for learning, memory and emotion. Overall, when wakefulness occurs at appropriate internal biological times, circadian clockwork benefits human cognitive and emotion function throughout the lifespan. Yet, when wakefulness occurs at inappropriate biological times because of environmental pressures (e.g., early school start times, long work hours that include work at night, shift work, jet lag or because of circadian rhythm sleep disorders, the resulting misalignment between circadian and wakefulness-sleep physiology leads to impaired cognitive performance, learning, emotion, and safety.

  13. A circadian clock in Antarctic krill: an endogenous timing system governs metabolic output rhythms in the euphausid species Euphausia superba.

    Directory of Open Access Journals (Sweden)

    Mathias Teschke

    Full Text Available Antarctic krill, Euphausia superba, shapes the structure of the Southern Ocean ecosystem. Its central position in the food web, the ongoing environmental changes due to climatic warming, and increasing commercial interest on this species emphasize the urgency of understanding the adaptability of krill to its environment. Krill has evolved rhythmic physiological and behavioral functions which are synchronized with the daily and seasonal cycles of the complex Southern Ocean ecosystem. The mechanisms, however, leading to these rhythms are essentially unknown. Here, we show that krill possesses an endogenous circadian clock that governs metabolic and physiological output rhythms. We found that expression of the canonical clock gene cry2 was highly rhythmic both in a light-dark cycle and in constant darkness. We detected a remarkable short circadian period, which we interpret as a special feature of the krill's circadian clock that helps to entrain the circadian system to the extreme range of photoperiods krill is exposed to throughout the year. Furthermore, we found that important key metabolic enzymes of krill showed bimodal circadian oscillations (∼9-12 h period in transcript abundance and enzymatic activity. Oxygen consumption of krill showed ∼9-12 h oscillations that correlated with the temporal activity profile of key enzymes of aerobic energy metabolism. Our results demonstrate the first report of an endogenous circadian timing system in Antarctic krill and its likely link to metabolic key processes. Krill's circadian clock may not only be critical for synchronization to the solar day but also for the control of seasonal events. This study provides a powerful basis for the investigation into the mechanisms of temporal synchronization in this marine key species and will also lead to the first comprehensive analyses of the circadian clock of a polar marine organism through the entire photoperiodic cycle.

  14. [Circadian rhythms and temperature homeostasis in monkeys during a flight on the Kosmos 1514 biosatellite

    Science.gov (United States)

    Klimovitskui, V. Ia; Alpatov, A. M.; Salzman, F. M.; Fuller, C. A.; Moore-Ede, M. S.

    1987-01-01

    In the course of a 5-day space flight of two rhesus-monkeys the following parameters were recorded at an interval of 16 min: core body temperature (Tc), skin temperature (Ts), and motor activity (MA). The telemetric Tc sensor was implanted subcutaneously in the right axilla, Ts thermistor was attached to the right ankle, and the MA piezotape was fixed to the inner side of the vest. Circadian rhythms of Tc varied with a period of 24 hours in one monkey and 25 hours in the other. The daily Tc decreased on the average by 0.5 degrees C, Ts fell immediately after launch and remained close to the lower limit throughout the flight. The Ts amplitude decreased 5-fold. Phases of the circadian rhythms of Ts changed and circadian rhythms of MA remained unchanged and equal to 24 hours.

  15. The Use of Routine Wrist Radiography is Not Useful in the Evaluation of Patients with a Ganglion Cyst of the Wrist

    OpenAIRE

    Andrew S. Wong; Jebson, Peter J.L.; Murray, Peter M.; Trigg, Stephen D.

    2007-01-01

    The purpose of this study was to evaluate the cost-effectiveness of routine wrist radiography in the evaluation of patients with a wrist ganglion. In the setting of a University-based hand surgery practice, 103 consecutive patients with a dorsal or volar wrist ganglion underwent posteroanterior, lateral, and oblique radiographs of the involved wrist. There were 24 men and 79 women with an average age of 34 years (range 4–67 years). A retrospective review of the medical records was performed. ...

  16. Circadian glomerular function: from physiology to molecular and therapeutical aspects.

    Science.gov (United States)

    Wuerzner, Grégoire; Firsov, Dmitri; Bonny, Olivier

    2014-08-01

    Life on earth is rhythmic by essence due to day/night alternation, and many biological processes are also cyclic. The kidney has a special role in the organism, controlling electrolytes and water balance, blood pressure, elimination of metabolic waste and xenobiotics and the production of several hormones. The kidney is submitted to changes throughout 24 h with periods of intense activity followed by calmer periods. Filtration, reabsorption and secretion are the three components determining renal function. Here, we review circadian changes related to glomerular function and proteinuria and emphasize the role of the clock in these processes. PMID:24516223

  17. Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome.

    Science.gov (United States)

    Zukowski, Lisa A; Roper, Jaimie A; Shechtman, Orit; Otzel, Dana M; Hovis, Patty W; Tillman, Mark D

    2014-01-01

    Among conventional manual wheelchair (CMW) users, 49% to 63% experience carpal tunnel syndrome (CTS) that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM) tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury participated. Motion data were captured as participants propelled across a flat surface, completing five trials in a CMW and five trials in the same CMW fitted with the EHDM. Average angular wrist orientations were compared between the two propulsion styles. Use of the EHDM resulted in reduced wrist extension and ulnar deviation. The shift to more neutral wrist orientations observed with EHDM use may reduce median nerve compression. PMID:25856042

  18. Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome

    Directory of Open Access Journals (Sweden)

    Lisa A. Zukowski, MA

    2015-03-01

    Full Text Available Among conventional manual wheelchair (CMW users, 49% to 63% experience carpal tunnel syndrome (CTS that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury participated. Motion data were captured as participants propelled across a flat surface, completing five trials in a CMW and five trials in the same CMW fitted with the EHDM. Average angular wrist orientations were compared between the two propulsion styles. Use of the EHDM resulted in reduced wrist extension and ulnar deviation. The shift to more neutral wrist orientations observed with EHDM use may reduce median nerve compression.

  19. [Circadian clock and non-visual functions: the role of light in humans].

    Science.gov (United States)

    Gronfier, Claude

    2014-01-01

    Hormonal secretion, cognitive performance, motor activity, metabolic processes, the sleep wake cycle and, most recently shown, cell division and ADN repair show a 24 h rhythmicity that is driven by the circadian timing system (the biological clock). Their appropriate activity over the 24 h requires appropriate entrainment of the circadian clock, which is achieved through the synchronizing effects of ocular light exposure. The activation of melanopsin-expressing ganglion cells in the retina depends on timing, quality, intensity, and history of light exposure. Inappropriate lighting leads to inappropriate synchronization of the clock, and activation of non-visual functions (mood, wakefulness, cognition, etc.). In turn, a deficit of circadian entrainment to the 24 h is responsible for alterations of a large number of functions, and leads to altered sleep, wake, mood, neurobehavioral processes and cell division, but also to pathologies. The crucial role of the circadian clock and the nature of the non-visual functions activated by light give rise to the concept that light is a biological need fundamental to health. Without an appropriate light hygiene, the clock receives an odd tempo, and it is cacophony! PMID:25840452

  20. Optimal implementations for reliable circadian clocks.

    Science.gov (United States)

    Hasegawa, Yoshihiko; Arita, Masanori

    2014-09-01

    Circadian rhythms are acquired through evolution to increase the chances for survival through synchronizing with the daylight cycle. Reliable synchronization is realized through two trade-off properties: regularity to keep time precisely, and entrainability to synchronize the internal time with daylight. We find by using a phase model with multiple inputs that achieving the maximal limit of regularity and entrainability entails many inherent features of the circadian mechanism. At the molecular level, we demonstrate the role sharing of two light inputs, phase advance and delay, as is well observed in mammals. At the behavioral level, the optimal phase-response curve inevitably contains a dead zone, a time during which light pulses neither advance nor delay the clock. We reproduce the results of phase-controlling experiments entrained by two types of periodic light pulses. Our results indicate that circadian clocks are designed optimally for reliable clockwork through evolution. PMID:25238386

  1. Circadian pattern in cerebro vascular disorders.

    Directory of Open Access Journals (Sweden)

    Bhalla A

    2002-10-01

    Full Text Available Over the last decade, various studies have been reported to evaluate the circadian pattern of cardiovascular and cerebro-vascular diseases. The data from Indian population is lacking. We undertook this prospective observational study to evaluate the circadian variation in disorders like cerebro-vascular accidents and transient ischemic attacks. Total of 146 patients (events were studied. Only 10 patients had TIA′s. 55% had hemorrhage and 45% had infarction. The 24 hours period was divided into 6 equal portions of 4 hours each. The maximum events were seen between 4 am to 8 am and 12 noon to 4 pm (23.28% each. Minimum events were seen between 12 midnight to 4 am 14/146 - 9.58%. The circadian variation in occurrence of cerebro-vascular disorders was present with two equal peaks.

  2. Circadian oscillators in the mouse brain

    DEFF Research Database (Denmark)

    Rath, Martin F; Rovsing, Louise; Møller, Morten

    2014-01-01

    The circadian timekeeper of the mammalian brain resides in the suprachiasmatic nucleus of the hypothalamus (SCN), and is characterized by rhythmic expression of a set of clock genes with specific 24-h daily profiles. An increasing amount of data suggests that additional circadian oscillators...... residing outside the SCN have the capacity to generate peripheral circadian rhythms. We have recently shown the presence of SCN-controlled oscillators in the neocortex and cerebellum of the rat. The function of these peripheral brain clocks is unknown, and elucidating this could involve mice with...... conditional cell-specific clock gene deletions. This prompted us to analyze the molecular clockwork of the mouse neocortex and cerebellum in detail. Here, by use of in situ hybridization and quantitative RT-PCR, we show that clock genes are expressed in all six layers of the neocortex and the Purkinje and...

  3. Quantification of circadian rhythms in single cells.

    Directory of Open Access Journals (Sweden)

    Pål O Westermark

    2009-11-01

    Full Text Available Bioluminescence techniques allow accurate monitoring of the circadian clock in single cells. We have analyzed bioluminescence data of Per gene expression in mouse SCN neurons and fibroblasts. From these data, we extracted parameters such as damping rate and noise intensity using two simple mathematical models, one describing a damped oscillator driven by noise, and one describing a self-sustained noisy oscillator. Both models describe the data well and enabled us to quantitatively characterize both wild-type cells and several mutants. It has been suggested that the circadian clock is self-sustained at the single cell level, but we conclude that present data are not sufficient to determine whether the circadian clock of single SCN neurons and fibroblasts is a damped or a self-sustained oscillator. We show how to settle this question, however, by testing the models' predictions of different phases and amplitudes in response to a periodic entrainment signal (zeitgeber.

  4. Musculoskeletal integration at the wrist underlies the modular development of limb tendons.

    Science.gov (United States)

    Huang, Alice H; Riordan, Timothy J; Pryce, Brian; Weibel, Jennifer L; Watson, Spencer S; Long, Fanxin; Lefebvre, Veronique; Harfe, Brian D; Stadler, H Scott; Akiyama, Haruhiko; Tufa, Sara F; Keene, Douglas R; Schweitzer, Ronen

    2015-07-15

    The long tendons of the limb extend from muscles that reside in the zeugopod (arm/leg) to their skeletal insertions in the autopod (paw). How these connections are established along the length of the limb remains unknown. Here, we show that mouse limb tendons are formed in modular units that combine to form a functional contiguous structure; in muscle-less limbs, tendons develop in the autopod but do not extend into the zeugopod, and in the absence of limb cartilage the zeugopod segments of tendons develop despite the absence of tendons in the autopod. Analyses of cell lineage and proliferation indicate that distinct mechanisms govern the growth of autopod and zeugopod tendon segments. To elucidate the integration of these autopod and zeugopod developmental programs, we re-examined early tendon development. At E12.5, muscles extend across the full length of a very short zeugopod and connect through short anlagen of tendon progenitors at the presumptive wrist to their respective autopod tendon segment, thereby initiating musculoskeletal integration. Zeugopod tendon segments are subsequently generated by proximal elongation of the wrist tendon anlagen, in parallel with skeletal growth, underscoring the dependence of zeugopod tendon development on muscles for tendon anchoring. Moreover, a subset of extensor tendons initially form as fused structures due to initial attachment of their respective wrist tendon anlage to multiple muscles. Subsequent individuation of these tendons depends on muscle activity. These results establish an integrated model for limb tendon development that provides a framework for future analyses of tendon and musculoskeletal phenotypes. PMID:26062940

  5. Modelling of intercellular synchronization in the Drosophila circadian clock

    Institute of Scientific and Technical Information of China (English)

    Wang Jun-Wei; Chen Ai-Min; Zhang Jia-Jun; Yuan Zhan-Jiang; Zhou Tian-Shou

    2009-01-01

    In circadian rhythm generation, intercellular signaling factors are shown to play a crucial role in both sustaining intrinsic cellular rhythmicity and acquiring collective behaviours across a population of circadian neurons. However, the physical mechanism behind their role remains to be fully understood. In this paper, we propose an indirectly coupled multicellular model for the synchronization of Drosophila circadian oscillators combining both intracellular and intercellular dynamics. By simulating different experimental conditions, we find that such an indirect coupling way can synchronize both heterogeneous self-sustained circadian neurons and heterogeneous mutational damped circadian neurons. Moreover, they can also be entrained to ambient light-dark (LD) cycles depending on intercellular signaling.

  6. Neural and Nonneural Contributions to Wrist Rigidity in Parkinson’s Disease: An Explorative Study Using the NeuroFlexor

    Directory of Open Access Journals (Sweden)

    H. Zetterberg

    2015-01-01

    Full Text Available Objective. The NeuroFlexor is a novel method incorporating a biomechanical model for the measurement of neural and nonneural contributions to resistance induced by passive stretch. In this study, we used the NeuroFlexor method to explore components of passive movement resistance in the wrist and finger muscles in subjects with Parkinson’s disease (PD. Methods. A cross-sectional comparison was performed in twenty-five subjects with PD with clinically identified rigidity and 14 controls. Neural (NC, elastic (EC, and viscous (VC components of the resistance to passive extension of the wrist were calculated using the NeuroFlexor. Measurements were repeated during a contralateral activation maneuver. Results. PD subjects showed greater total resistance (P<0.001 and NC (P=0.002 compared to controls. EC and VC did not differ significantly between groups. Contralateral activation maneuver resulted in increased NC in the PD group but this increase was due to increased resting tension. Total resistance and NC correlated with clinical ratings of rigidity and with bradykinesia. Conclusions. The findings suggest that stretch induced reflex activity, but not nonneural resistance, is the major contributor to rigidity in wrist muscles in PD. The NeuroFlexor is a potentially valuable clinical and research tool for quantification of rigidity.

  7. EEG and ocular correlates of circadian melatonin phase and human performance decrements during sleep loss

    Science.gov (United States)

    Cajochen, C.; Khalsa, S. B.; Wyatt, J. K.; Czeisler, C. A.; Dijk, D. J.

    1999-01-01

    The aim of this study was to quantify the associations between slow eye movements (SEMs), eye blink rate, waking electroencephalogram (EEG) power density, neurobehavioral performance, and the circadian rhythm of plasma melatonin in a cohort of 10 healthy men during up to 32 h of sustained wakefulness. The time course of neurobehavioral performance was characterized by fairly stable levels throughout the first 16 h of wakefulness followed by deterioration during the phase of melatonin secretion. This deterioration was closely associated with an increase in SEMs. Frontal low-frequency EEG activity (1-7 Hz) exhibited a prominent increase with time awake and little circadian modulation. EEG alpha activity exhibited circadian modulation. The dynamics of SEMs and EEG activity were phase locked to changes in neurobehavioral performance and lagged the plasma melatonin rhythm. The data indicate that frontal areas of the brain are more susceptible to sleep loss than occipital areas. Frontal EEG activity and ocular parameters may be used to monitor and predict changes in neurobehavioral performance associated with sleep loss and circadian misalignment.

  8. Circadian temperature and melatonin rhythms, sleep, and neurobehavioral function in humans living on a 20-h day

    Science.gov (United States)

    Wyatt, J. K.; Ritz-De Cecco, A.; Czeisler, C. A.; Dijk, D. J.

    1999-01-01

    The interaction of homeostatic and circadian processes in the regulation of waking neurobehavioral functions and sleep was studied in six healthy young subjects. Subjects were scheduled to 15-24 repetitions of a 20-h rest/activity cycle, resulting in desynchrony between the sleep-wake cycle and the circadian rhythms of body temperature and melatonin. The circadian components of cognitive throughput, short-term memory, alertness, psychomotor vigilance, and sleep disruption were at peak levels near the temperature maximum, shortly before melatonin secretion onset. These measures exhibited their circadian nadir at or shortly after the temperature minimum, which in turn was shortly after the melatonin maximum. Neurobehavioral measures showed impairment toward the end of the 13-h 20-min scheduled wake episodes. This wake-dependent deterioration of neurobehavioral functions can be offset by the circadian drive for wakefulness, which peaks in the latter half of the habitual waking day during entrainment. The data demonstrate the exquisite sensitivity of many neurobehavioral functions to circadian phase and the accumulation of homeostatic drive for sleep.

  9. Wrist range of motion and motion frequency during toy and game play with a joint-specific controller specially designed to provide neuromuscular therapy: A proof of concept study in typically developing children.

    Science.gov (United States)

    Crisco, Joseph J; Schwartz, Joel B; Wilcox, Bethany; Brideau, Holly; Basseches, Benjamin; Kerman, Karen

    2015-08-20

    Upper extremities affected by hemiplegic cerebral palsy (CP) and other neuromuscular disorders have been demonstrated to benefit from therapy, and the greater the duration of the therapy, the greater the benefit. A great motivator for participating in and extending the duration of therapy with children is play. Our focus is on active motion therapy of the wrist and forearm. In this study we examine the wrist motions associated with playing with two toys and three computer games controlled by a specially-designed play controller. Twenty children (ages 5-11) with no diagnosis of a muscular disorder were recruited. The play controller was fitted to the wrist and forearm of each child and used to measure and log wrist flexion and extension. Play activity and enjoyment were quantified by average wrist range of motion (ROM), motion frequency measures, and a discrete visual scale. We found significant differences in the average wrist ROM and motion frequency among the toys and games, yet there were no differences in the level of enjoyment across all toys and games, which was high. These findings indicate which toys and games may elicit the greater number of goal-directed movements, and lay the foundation for our long-term goal to develop and evaluate innovative motion-specific play controllers that are engaging rehabilitative devices for enhancing therapy and promoting neural plasticity and functional recovery in children with CP. PMID:25935686

  10. Development of circadian oscillators in neurosphere cultures during adult neurogenesis.

    Directory of Open Access Journals (Sweden)

    Astha Malik

    Full Text Available Circadian rhythms are common in many cell types but are reported to be lacking in embryonic stem cells. Recent studies have described possible interactions between the molecular mechanism of circadian clocks and the signaling pathways that regulate stem cell differentiation. Circadian rhythms have not been examined well in neural stem cells and progenitor cells that produce new neurons and glial cells during adult neurogenesis. To evaluate circadian timing abilities of cells undergoing neural differentiation, neurospheres were prepared from the mouse subventricular zone (SVZ, a rich source of adult neural stem cells. Circadian rhythms in mPer1 gene expression were recorded in individual spheres, and cell types were characterized by confocal immunofluorescence microscopy at early and late developmental stages in vitro. Circadian rhythms were observed in neurospheres induced to differentiate into neurons or glia, and rhythms emerged within 3-4 days as differentiation proceeded, suggesting that the neural stem cell state suppresses the functioning of the circadian clock. Evidence was also provided that neural stem progenitor cells derived from the SVZ of adult mice are self-sufficient clock cells capable of producing a circadian rhythm without input from known circadian pacemakers of the organism. Expression of mPer1 occurred in high frequency oscillations before circadian rhythms were detected, which may represent a role for this circadian clock gene in the fast cycling of gene expression responsible for early cell differentiation.

  11. Cognitive dysfunction, elevated anxiety and reduced cocaine response in circadian clock-deficient cryptochrome knockout mice

    Directory of Open Access Journals (Sweden)

    Emmanuel Valjent

    2013-10-01

    Full Text Available The circadian clock comprises a set of genes involved in cell-autonomous transcriptional feedback loops that orchestrate the expression of a range of downstream genes, driving circadian patterns of behavior. Cognitive dysfunction, mood disorders, anxiety disorders and substance abuse disorders have been associated with disruptions in circadian rhythm and circadian clock genes, but the causal relationship of these associations is still poorly understood. In the present study, we investigate the effect of genetic disruption of the circadian clock, through deletion of both paralogs of the core gene cryptochrome (Cry1 and Cry2. Mice lacking Cry1 and Cry2 (Cry1-/-Cry2-/- displayed attenuated dark phase and novelty-induced locomotor activity. Moreover, they showed impaired recognition memory but intact fear memory. Depression-related behaviors in the forced swim test or sucrose preference tests were unaffected but Cry1-/-Cry2-/- mice displayed increased anxiety in the open field and elevated plus maze tests. Finally, hyperlocomotion and striatal phosphorylation of extracellular signal-regulated kinase (ERK induced by a single cocaine administration are strongly reduced in Cry1-/-Cry2-/- mice. Interestingly, only some behavioral measures were affected in mice lacking either Cry1 or Cry2. Notably, recognition memory was impaired in both Cry1-/-Cry2+/+ and Cry1+/+Cry2-/- mice. Moreover, we further observed elevated anxiety in Cry1-/-Cry2+/+ and Cry1+/+Cry2-/- mice. Our data indicate that beyond their role in the control of circadian rhythm, cryptochrome genes have a direct influence in cognitive function, anxiety-related behaviors and sensitivity to psychostimulant drugs.

  12. Cognitive dysfunction, elevated anxiety, and reduced cocaine response in circadian clock-deficient cryptochrome knockout mice.

    Science.gov (United States)

    De Bundel, Dimitri; Gangarossa, Giuseppe; Biever, Anne; Bonnefont, Xavier; Valjent, Emmanuel

    2013-01-01

    The circadian clock comprises a set of genes involved in cell-autonomous transcriptional feedback loops that orchestrate the expression of a range of downstream genes, driving circadian patterns of behavior. Cognitive dysfunction, mood disorders, anxiety disorders, and substance abuse disorders have been associated with disruptions in circadian rhythm and circadian clock genes, but the causal relationship of these associations is still poorly understood. In the present study, we investigate the effect of genetic disruption of the circadian clock, through deletion of both paralogs of the core gene cryptochrome (Cry1 and Cry2). Mice lacking Cry1 and Cry2 (Cry1(-/-)Cry2(-/-) ) displayed attenuated dark phase and novelty-induced locomotor activity. Moreover, they showed impaired recognition memory but intact fear memory. Depression-related behaviors in the forced swim test or sucrose preference tests were unaffected but Cry1(-/-)Cry2(-/-) mice displayed increased anxiety in the open field and elevated plus maze tests. Finally, hyperlocomotion and striatal phosphorylation of extracellular signal-regulated kinase (ERK) induced by a single cocaine administration are strongly reduced in Cry1(-/-)Cry2(-/-) mice. Interestingly, only some behavioral measures were affected in mice lacking either Cry1 or Cry2. Notably, recognition memory was impaired in both Cry1(-/-)Cry2(+/+) and Cry1(+/+)Cry2(-/-) mice. Moreover, we further observed elevated anxiety in Cry1(-/-)Cry2(+/+) and Cry1(+/+)Cry2(-/-) mice. Our data indicate that beyond their role in the control of circadian rhythm, cryptochrome genes have a direct influence in cognitive function, anxiety-related behaviors and sensitivity to psychostimulant drugs. PMID:24187535

  13. Detailed analysis of contrast-enhanced MRI of hands and wrists in patients with psoriatic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Tehranzadeh, Jamshid [University of California, Department of Radiological Sciences, Irvine (United States); University of California Medical Center, Department of Radiological Sciences R-140, Orange, CA (United States); Ashikyan, Oganes; Anavim, Arash; Shin, John [University of California, Department of Radiological Sciences, Irvine (United States)

    2008-05-15

    The objective was to perform detailed analysis of the involved soft tissues, tendons, joints, and bones in the hands and wrists of patients with psoriatic arthritis (PsA). We reviewed 23 contrast-enhanced MR imaging studies (13 hands and 10 wrists) in 10 patients with the clinical diagnosis of PsA. We obtained clinical information from medical records and evaluated images for the presence of erosions, bone marrow edema, joint synovitis, tenosynovitis, carpal tunnel, and soft tissue involvement. Two board-certified musculoskeletal radiologists reviewed all images independently. Differences were resolved during a subsequent joint session. The average duration of disease was 71.3 months, ranging from 1 month to 25 years. Eight of the 10 wrists (80%) and 6 of the 13 hands demonstrated bone erosions. Bone marrow abnormalities were shown in 5 of the 10 wrists (50%) and 4 of the 14 hands (31%). Triangular fibrocartilage tears were seen in 6 of the 10 wrists (60%). Wrist and hand joint synovitis were present in all studies (67 wrist joints and 101 hand joints). Wrist soft tissue involvement was detected in 9 of the 10 wrists (90%) and hand soft tissue involvement was present in 12 of the 13 wrists (92%). Findings adjacent to the region of soft tissue involvement included synovitis (4 wrists) and tenosynovitis (3 wrists). Bone marrow edema adjacent to the region of soft tissue involvement was seen in one wrist. Bulge of the flexor retinaculum was seen in 4 of the 10 wrists (40%) and median nerve enhancement was seen in 8 of the 10 wrists (80%). Tenosynovitis was seen in all studies (all 10 of the hands and all 13 of the wrists). The 'rheumatoid' type of distribution of bony lesions was common in our study. Interobserver agreement for various findings ranged from 83% to 100%. Contrast-enhanced MRI unequivocally demonstrated bone marrow edema, erosions, tendon and soft-tissue disease, and median nerve involvement, with good interobserver reliability in patients with

  14. Intra-articular distribution pattern after ultrasound-guided injections in wrist joints of patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Boesen, Mikael; Jensen, Karl Erik; Torp-Pedersen, Søren;

    2007-01-01

    /ml), 0.5 ml Lidocaine (5mg/ml) and 0.15 ml gadolinium (Omniscan 0.5 mmol/ml). The drug solution was placed in the central proximal part of the wrist between the distal radius and the lunate bone. Coronal and axial MRI sequences were performed after the injection to visualize the distribution. Carpal...... to the clinical parameters and the MRI OMERACT scores. RESULTS: No uniform pattern was seen in the distribution of the contrast. Only two patients had full contrast distribution to all four compartments, and the mean distribution count for all patients was 2.4 (range 0.5-4). The distribution count...... correlated with the MRI OMERACT synovitis score (r=0.60, p=0.014), but not with the erosions, bonemarrow oedema scores or any clinical parameters. CONCLUSION: The distribution of contrast on MRI showed patient specific and random patterns after IA injections in active RA wrist joints. The degree of...

  15. Restoring ADL function after wrist surgery in children with cerebral palsy: a novel Bilateral robot system design.

    Science.gov (United States)

    Holley, D; Theriault, A; Kamara, S; Anewenter, V; Hughes, D; Johnson, M J

    2013-06-01

    Cerebral palsy is a leading cause of disability in children and reducing its effects on arm function will improve quality of life. Our goal is to train children with CP after wrist tendon transfer surgery using a robotic therapy system consisting of two robot arms and wrist robots. The therapeutic goal is to determine if the robot training combined with surgery intervention improved functional outcomes significantly more than surgery alone. To accomplish this long-term goal we have developed a Bilateral ADL Exercise Robot, BiADLER aimed at training children with CP in reach to grasp coordination on ADLs. Specifically, the robot will provide active training using an assist-as-needed. This paper presents the design concepts. PMID:24187280

  16. Retinal circadian clocks and non-visual photoreceptors: light input to the circadian system.

    OpenAIRE

    Ouria Dkhissi-Benyahya

    2013-01-01

    The mammalian retina contains an endogenous pacemaker that regulates retinal physiology and adjusts daily the temporal phase of the central circadian timing system with environmental time. This entrainment process involves rods, cones and melanopsin-expressing retinal ganglion cells. In contrast with non mammalian retinas, in which the clock has been identified in photoreceptors, the location of the retinal circadian clock in mammals is still controversial. In addition, the impact of specific...

  17. CULLIN-3 controls TIMELESS oscillations in the Drosophila circadian clock.

    Directory of Open Access Journals (Sweden)

    Brigitte Grima

    Full Text Available Eukaryotic circadian clocks rely on transcriptional feedback loops. In Drosophila, the PERIOD (PER and TIMELESS (TIM proteins accumulate during the night, inhibit the activity of the CLOCK (CLK/CYCLE (CYC transcriptional complex, and are degraded in the early morning. The control of PER and TIM oscillations largely depends on post-translational mechanisms. They involve both light-dependent and light-independent pathways that rely on the phosphorylation, ubiquitination, and proteasomal degradation of the clock proteins. SLMB, which is part of a CULLIN-1-based E3 ubiquitin ligase complex, is required for the circadian degradation of phosphorylated PER. We show here that CULLIN-3 (CUL-3 is required for the circadian control of PER and TIM oscillations. Expression of either Cul-3 RNAi or dominant negative forms of CUL-3 in the clock neurons alters locomotor behavior and dampens PER and TIM oscillations in light-dark cycles. In constant conditions, CUL-3 deregulation induces behavioral arrhythmicity and rapidly abolishes TIM cycling, with slower effects on PER. CUL-3 affects TIM accumulation more strongly in the absence of PER and forms protein complexes with hypo-phosphorylated TIM. In contrast, SLMB affects TIM more strongly in the presence of PER and preferentially associates with phosphorylated TIM. CUL-3 and SLMB show additive effects on TIM and PER, suggesting different roles for the two ubiquitination complexes on PER and TIM cycling. This work thus shows that CUL-3 is a new component of the Drosophila clock, which plays an important role in the control of TIM oscillations.

  18. Modeling an evolutionary conserved circadian cis-element.

    Directory of Open Access Journals (Sweden)

    Eric R Paquet

    2008-02-01

    Full Text Available Circadian oscillator networks rely on a transcriptional activator called CLOCK/CYCLE (CLK/CYC in insects and CLOCK/BMAL1 or NPAS2/BMAL1 in mammals. Identifying the targets of this heterodimeric basic-helix-loop-helix (bHLH transcription factor poses challenges and it has been difficult to decipher its specific sequence affinity beyond a canonical E-box motif, except perhaps for some flanking bases contributing weakly to the binding energy. Thus, no good computational model presently exists for predicting CLK/CYC, CLOCK/BMAL1, or NPAS2/BMAL1 targets. Here, we use a comparative genomics approach and first study the conservation properties of the best-known circadian enhancer: a 69-bp element upstream of the Drosophila melanogaster period gene. This fragment shows a signal involving the presence of two closely spaced E-box-like motifs, a configuration that we can also detect in the other four prominent CLK/CYC target genes in flies: timeless, vrille, Pdp1, and cwo. This allows for the training of a probabilistic sequence model that we test using functional genomics datasets. We find that the predicted sequences are overrepresented in promoters of genes induced in a recent study by a glucocorticoid receptor-CLK fusion protein. We then scanned the mouse genome with the fly model and found that many known CLOCK/BMAL1 targets harbor sequences matching our consensus. Moreover, the phase of predicted cyclers in liver agreed with known CLOCK/BMAL1 regulation. Taken together, we built a predictive model for CLK/CYC or CLOCK/BMAL1-bound cis-enhancers through the integration of comparative and functional genomics data. Finally, a deeper phylogenetic analysis reveals that the link between the CLOCK/BMAL1 complex and the circadian cis-element dates back to before insects and vertebrates diverged.

  19. Magnetic resonance imaging-determined synovial membrane volume as a marker of disease activity and a predictor of progressive joint destruction in the wrists of patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Hansen, M; Stoltenberg, M;

    1999-01-01

    OBJECTIVE: To evaluate the synovial membrane volume, determined by magnetic resonance imaging (MRI), as a marker of joint disease activity and a predictor of progressive joint destruction in rheumatoid arthritis (RA). METHODS: Twenty-six patients with RA, randomized to receive disease-modifying a......OBJECTIVE: To evaluate the synovial membrane volume, determined by magnetic resonance imaging (MRI), as a marker of joint disease activity and a predictor of progressive joint destruction in rheumatoid arthritis (RA). METHODS: Twenty-six patients with RA, randomized to receive disease......-Pratt analysis). The rate of erosive progression on MRI was highly correlated with baseline scores and, particularly, with area under the curve (AUC) values of synovial membrane volume (Spearman's sigma = 0.69, P < 0.001), but not with baseline or AUC values of local or global clinical or biochemical parameters...

  20. The value of quantitative evaluation of inlfammatory activity by using wrist dynamic contrast-enhanced MRI in rheumatoid arthritis%动态增强MRI定量评价类风湿性关节炎腕关节炎症活动度的价值

    Institute of Scientific and Technical Information of China (English)

    曾伟科; 莫颖倩; 张翔; 段小慧; 陈乐锋; 马剑达; 戴冽; 沈君

    2015-01-01

    目的:探讨动态增强MRI(DCE-MRI)定量评价类风湿性关节炎(RA)炎症活动度的价值。材料与方法20例经临床病理确诊的RA患者行双手腕关节DCE-MRI检查,滑膜病理Krenn评分、临床DAS28评分及血清学检查,运用动态增强专用血流动力学软件测量双腕关节滑膜病变区定量参数:容积转移常数(Ktrans)、速率常数(Kep)、血管外细胞外容积分数(Ve)、血浆容积(Vp)及半定量参数:达峰时间(TTP)、最大浓度(Cmax)、浓度-时间曲线下面积(AUC)、最大斜率(Slopemax),分析DCE-MRI定量及半定量参数与滑膜病理Krenn评分、临床DAS28评分及血清学检查各指标之间的相关性,采用t检验比较分析滑膜炎症不同活动度组间Ktrans值的差异。结果20例RA腕关节滑膜病变Ktrans值为(1.27±0.59) ml/min, Krenn评分为3.38±1.53,DAS28评分为4.80±0.94。6例滑膜炎症为重度,11例滑膜炎症为轻度。Ktrans与Krenn评分、DAS28具有正相关(r=0.698,P<0.01;r=0.510, P<0.05),Kep、Ve、Vp及TTP、Cmax、AUC、Slopemax与Krenn评分、DAS28及血清学检查各指标之间无相关性(P>0.05)。滑膜炎症重度组Ktrans值明显高于轻度组(t=4.05,P<0.01)。结论 DCE-MRI的Ktrans值可用于反映RA患者临床及滑膜病变的炎症活动程度。%Objective: To investigate the value of quantitative evaluation of inflammatory activity by using wrist dynamic contrast-enhanced MRI (DCE-MRI) in rheumatoid arthritis (RA) patients.Materials and Methods: Twenty patients with clinically and pathologically proved RA underwent wrist DCE-MRI examination, Krenn scoring of synovial inflammatory, clinical scoring of DAS28 and serological examination. Quantitative parameters including the volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular volume fraction (Ve), plasma volume (Vp) and semi-quantitative parameters including the time to peak (TTP), maximum concentration(Cmax), the

  1. Rheumatoid wrist deformity and risk of extensor tendon rupture evaluated by 3DCT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Hajime; Abe, Asami; Murasawa, Akira; Nakazono, Kiyoshi; Horizono, Hidehiro; Ishii, Katsushi; Seki, Eiko [Niigata Rheumatic Center, Department of Rheumatology, Shibata city, Niigata (Japan)

    2010-05-15

    Extensor tendon rupture on the dorsum of the wrist is commonly seen in patients with rheumatoid arthritis (RA). It causes immediate dysfunction of the hand and surgical reconstruction is usually required. The purpose of this study was to clarify the risk of extensor tendon rupture by quantifying wrist deformity on three-dimensional computed tomography (3DCT) images. Three-dimensional CT images of 108 wrists in 102 patients with RA and 38 wrists in 38 healthy volunteers were analyzed retrospectively. All of the rheumatoid wrists had caused persistent pain for more than 6 months despite ongoing medical treatment. Extensor tendon rupture was noted in 49 wrists in 47 patients, and no rupture was noted in 59 wrists in 56 patients. The dorsal subluxation ratio (DSR) of the ulnar head and the carpal supination angle (CSA) were measured utilizing a new technique. The average DSR and CSA in the rupture group (n = 49), the non-rupture group (n = 59), and the normal wrist group (n = 38) were 37%, 19%, and 26%, and 15 , 11 , and 6 respectively. The cut-off values for extensor tendon rupture in the wrists of patients with RA were 32% (sensitivity; 70%, specificity; 75%) in the DSR, and 14 (71%, 68%) in the CSA. By utilizing 3DCT imaging of the rheumatoid wrist, these parameters can help improve our ability to predict extensor tendon rupture. (orig.)

  2. A clinical decision rule for the use of plain radiography in children after acute wrist injury: development and external validation of the Amsterdam Pediatric Wrist Rules

    NARCIS (Netherlands)

    A. Slaar (Annelie); M.M.J. Walenkamp (Monique); A. Bentohami (Abdelali); M. Maas (Mario); R.R. van Rijn (Rick); E.W. Steyerberg (Ewout); L.C. Jager (L. Cara); N.L. Sosef (Nico L.); R. van Velde (Romuald); J.M. Ultee (Jan); J.C. Goslings (Carel); N.W.L. Schep (Niels)

    2016-01-01

    textabstractBackground: In most hospitals, children with acute wrist trauma are routinely referred for radiography. Objective: To develop and validate a clinical decision rule to decide whether radiography in children with wrist trauma is required. Materials and methods: We prospectively developed a

  3. Insights into the role of the habenular circadian clock in addiction

    Directory of Open Access Journals (Sweden)

    Nora L Salaberry

    2016-01-01

    Full Text Available Drug addiction is a brain disease involving alterations in anatomy and functional neural communication. Drug intake and toxicity show daily rhythms in both humans and rodents. Evidence concerning the role of clock genes in drug intake has been previously reported. However, the implication of a timekeeping brain locus is much less known. The epithalamic lateral habenula (LHb is now emerging as a key nucleus in drug intake and addiction. This brain structure modulates the activity of dopaminergic neurons from the ventral tegmental area, a central part of the reward system. Moreover, the LHb has circadian properties: LHb cellular activity (i.e., firing rate and clock genes expression oscillates in a 24h range, and the nucleus is affected by photic stimulation and has anatomical connections with the main circadian pacemaker, the suprachiasmatic nucleus. Here, we describe the current insights on the role of the LHb as a circadian oscillator and its possible implications on the rhythmic regulation of the dopaminergic activity and drug intake. This data could inspire new strategies to treat drug addiction, considering circadian timing as a principal factor.

  4. MR imaging in suspected acute trauma of wrist bones

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the findings of MR imaging compared to plain radiography in acute wrist trauma. Radiography and MR imaging (obtained at 1.5 T) of 67 patients (38 female, 29 male, aged 15-80 years) were analysed by three senior radiologists in a blinded random fashion. One-third (n= 13) of the 37 fractures observed on MR images were missed on the radiographs. The McNemar test indicated significant differences in diagnoses between radiography and MR. We recommend that MR imaging should be considered in the diagnosis of acute wrist trauma when: 1) There is a clear discrepancy between the clinical status and a negative radiography and when splint treatment would increase cost by causing occupational restrictions; and 2) Healing of trauma diagnosed as contusion or distension does not occur within the expected time

  5. Pose Tracking Algorithm of an Endoscopic Surgery Robot Wrist

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Yin, H L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Meng, Q [Shanghai University of Electric Power (China)

    2006-10-15

    In recent two decades, more and more research on the endoscopic surgery has been carried out [2]. Most of the work focuses on the development of the robot in the field of robotics and the navigation of the surgery tools based on computer graphics. But the tracking and locating of the EndoWrist is also a very important aspect. This paper deals with the the tracking algorithm of the EndoWrist's pose (position and orientation). The linear tracking of the position is handled by the Kalman Filter. The quaternion-based nonlinear orientation tracking is implemented with the Extended Kalman Filter. The most innovative point of this paper is the parameterization of the motion model of the Extended Kalman Filter.

  6. Circadian clock and the onset of cardiovascular events.

    Science.gov (United States)

    Takeda, Norihiko; Maemura, Koji

    2016-06-01

    The onset of cardiovascular diseases often shows time-of-day variation. Acute myocardial infarction or ventricular arrhythmia such as ventricular tachycardia occurs mainly in the early morning. Multiple biochemical and physiological parameters show circadian rhythm, which may account for the diurnal variation of cardiovascular events. These include the variations in blood pressure, activity of the autonomic nervous system and renin-angiotensin axis, coagulation cascade, vascular tone and the intracellular metabolism of cardiomyocytes. Importantly, the molecular clock system seems to underlie the circadian variation of these parameters. The center of the biological clock, also known as the central clock, exists in the suprachiasmatic nucleus. In contrast, the molecular clock system is also activated in each cell of the peripheral organs and constitute the peripheral clock. The biological clock system is currently considered to have a beneficial role in maintaining the homeostasis of each organ. Discoordination, however, between the peripheral clock and external environment could potentially underlie the development of cardiovascular events. Therefore, understanding the molecular and cellular pathways by which cardiovascular events occur in a diurnal oscillatory pattern will help the establishment of a novel therapeutic approach to the management of cardiovascular disorders. PMID:26888119

  7. WRIST ARTHRODESIS WITH MINIMAL FIXATION PRESERVING THE CARPOMETACARPAL JOINTS

    Science.gov (United States)

    Pardini, Arlindo Gomes; Pádua Gonçalves, Rodolfo Fonseca; Freitas, Afrânio Donato; Chaves, Antonio Barbosa

    2015-01-01

    Objective: Wrist arthrodesis is a surgical procedure that should always be considered in cases of pathological conditions in which anatomical and functional structures are altered. In general, the results are very satisfactory, particularly for pain relief, and in the majority of cases, there is considerable functional improvement. Various techniques have been described, with different methods of internal fixation, most of which include the carpometacarpal joints in the fusion. The objective of this study was to evaluate the results from wrist arthrodesis using a technique that is simpler, more biological, less expensive, and does not involve the carpometacarpal joints. Methods: Fifteen patients with wrist arthrodesis were evaluated (six with sequelae from trauma, four with rheumatoid arthritis, three with Kienbock grade IV, one with Preiser and one with panarthrosis). The technique consisted of using an iliac bone plate and internal fixation with Kirschner wires, avoiding the carpometacarpal joints. Results: The evaluation was based on consolidation time (93% in seven weeks); movements of the fingers and pronosupination; pinch and grasp strength; functional evaluation through the DASH, pain and patient satisfaction questionnaires. In general, the results were similar to those of other, more aggressive techniques, and the non-inclusion of the carpometacarpal joints did not affect the final result. Conclusion: Wrist arthrodesis with fixation using Kirschner wires and an iliac bone plate, preserving the carpometacarpal joints, gives good or excellent results that are not inferior to those of other techniques that have been described. However, it presents major advantages over other methods: it is less aggressive and cheaper, and does not have the inconvenience and complications associated with the use of plates and screws. PMID:27022522

  8. Association between wrist angle and carpal tunnel syndrome among workers

    OpenAIRE

    You, Doohee

    2013-01-01

    Abstract Association between wrist angle and carpal tunnel syndrome among workersbyDoohee YouDoctor of Philosophy in Environmental Health Science University of California, Berkeley Professor David Rempel, Chair IntroductionCarpal Tunnel Syndrome (CTS) is the most common work-related peripheral neuropathy among workers who perform hand-intensive tasks. It has a greater impact on time away from work and disability than almost all other workplace injuries. For prevention, the National Institute ...

  9. Circadian metabolism in the light of evolution.

    Science.gov (United States)

    Gerhart-Hines, Zachary; Lazar, Mitchell A

    2015-06-01

    Circadian rhythm, or daily oscillation, of behaviors and biological processes is a fundamental feature of mammalian physiology that has developed over hundreds of thousands of years under the continuous evolutionary pressure of energy conservation and efficiency. Evolution has fine-tuned the body's clock to anticipate and respond to numerous environmental cues in order to maintain homeostatic balance and promote survival. However, we now live in a society in which these classic circadian entrainment stimuli have been dramatically altered from the conditions under which the clock machinery was originally set. A bombardment of artificial lighting, heating, and cooling systems that maintain constant ambient temperature; sedentary lifestyle; and the availability of inexpensive, high-calorie foods has threatened even the most powerful and ancient circadian programming mechanisms. Such environmental changes have contributed to the recent staggering elevation in lifestyle-influenced pathologies, including cancer, cardiovascular disease, depression, obesity, and diabetes. This review scrutinizes the role of the body's internal clocks in the hard-wiring of circadian networks that have evolved to achieve energetic balance and adaptability, and it discusses potential therapeutic strategies to reset clock metabolic control to modern time for the benefit of human health. PMID:25927923

  10. Circadian systems biology: When time matters

    Directory of Open Access Journals (Sweden)

    Luise Fuhr

    2015-01-01

    In this manuscript we review the combination of experimental methodologies, bioinformatics and theoretical models that have been essential to explore this remarkable timing-system. Such an integrative and interdisciplinary approach may provide new strategies with regard to chronotherapeutic treatment and new insights concerning the restoration of the circadian timing in clock-associated diseases.

  11. Circadian clockwork and entrainment during development

    Czech Academy of Sciences Publication Activity Database

    Sumová, Alena; Sládek, Martin; Kováčiková, Zuzana; El-Hennamy, Rehab; Laurinová, Kristýna; Bendová, Zdena; Illnerová, Helena

    Frankfurt/Main : J.W. Goethe- University, 2005. s. 55-55. [Congress of the EPBRS /10./. 01.09.2005-05.09.2005, Frankfurt/Main] Institutional research plan: CEZ:AV0Z50110509 Keywords : circadian clockwork * development Subject RIV: FH - Neurology

  12. Adaptation to experimental jet-lag in R6/2 mice despite circadian dysrhythmia.

    Directory of Open Access Journals (Sweden)

    Nigel I Wood

    Full Text Available The R6/2 transgenic mouse model of Huntington's disease (HD shows a disintegration of circadian rhythms that can be delayed by pharmacological and non-pharmacological means. Since the molecular machinery underlying the circadian clocks is intact, albeit progressively dysfunctional, we wondered if light phase shifts could modulate the deterioration in daily rhythms in R6/2 mice. Mice were subjected to four x 4 hour advances in light onset. R6/2 mice adapted to phase advances, although angles of entrainment increased with age. A second cohort was subjected to a jet-lag paradigm (6 hour delay or advance in light onset, then reversal after 2 weeks. R6/2 mice adapted to the original shift, but could not adjust accurately to the reversal. Interestingly, phase shifts ameliorated the circadian rhythm breakdown seen in R6/2 mice under normal LD conditions. Our previous finding that the circadian period (tau of 16 week old R6/2 mice shortens to approximately 23 hours may explain how they adapt to phase advances and maintain regular circadian rhythms. We tested this using a 23 hour period light/dark cycle. R6/2 mice entrained to this cycle, but onsets of activity continued to advance, and circadian rhythms still disintegrated. Therefore, the beneficial effects of phase-shifting are not due solely to the light cycle being closer to the tau of the mice. Our data show that R6/2 mice can adapt to changes in the LD schedule, even beyond the age when their circadian rhythms would normally disintegrate. Nevertheless, they show abnormal responses to changes in light cycles. These might be caused by a shortened tau, impaired photic re-synchronization, impaired light detection and/or reduced masking by evening light. If similar abnormalities are present in HD patients, they may suffer exaggerated jet-lag. Since the underlying molecular clock mechanism remains intact, light may be a useful treatment for circadian dysfunction in HD.

  13. The Effects of Spaceflight on the Rat Circadian Timing System

    Science.gov (United States)

    Fuller, Charles A.; Murakami, Dean M.; Hoban-Higgins, Tana M.; Fuller, Patrick M.; Robinson, Edward L.; Tang, I.-Hsiung

    2003-01-01

    Two fundamental environmental influences that have shaped the evolution of life on Earth are gravity and the cyclic changes occurring over the 24-hour day. Light levels, temperature, and humidity fluctuate over the course of a day, and organisms have adapted to cope with these variations. The primary adaptation has been the evolution of a biological timing system. Previous studies have suggested that this system, named the circadian (circa - about; dies - a day) timing system (CTS), may be sensitive to changes in gravity. The NASA Neurolab spaceflight provided a unique opportunity to evaluate the effects of microgravity on the mammalian CTS. Our experiment tested the hypotheses that microgravity would affect the period, phasing, and light sensitivity of the CTS. Twenty-four Fisher 344 rats were exposed to 16 days of microgravity on the Neurolab STS-90 mission, and 24 Fisher 344 rats were also studied on Earth as one-G controls. Rats were equipped with biotelemetry transmitters to record body temperature (T(sub b)) and heart rate (HR) continuously while the rats moved freely. In each group, 18 rats were exposed to a 24-hour light-dark (LD 12:12) cycle, and six rats were exposed to constant dim red-light (LL). The ability of light to induce a neuronal activity marker (c-fos) in the circadian pacemaker of the brain, the suprachiasmatic nucleus (SCN), was examined in rats studied on flight days two (FD2) and 14 (FD14), and postflight days two (R+1) and 14 (R+13). The flight rats in LD remained synchronized with the LD cycle. However, their T(sub b), rhythm was markedly phase-delayed relative to the LD cycle. The LD flight rats also had a decreased T(sub b) and a change in the waveform of the T(sub b) rhythm compared to controls. Rats in LL exhibited free-running rhythms of T(sub b), and HR; however, the periods were longer in microgravity. Circadian period returned to preflight values after landing. The internal phase angle between rhythms was different in flight than

  14. Role of MR imaging in chronic wrist pain

    International Nuclear Information System (INIS)

    Magnetic resonance (MR) imaging for chronic wrist pain is challenging. Correct assessment of the triangular fibrocartilage, hyaline cartilage, ligaments, and tendons has become mandatory for comprehensive decision making in wrist surgery. The MR technique, potential and limits of MR imaging in patients with chronic wrist pain will be discussed. MR arthrography with injection of gadolinium-containing contrast material into the distal radioulnar joint is suggested for evaluation of the triangular fibrocartilage. The clinically meaningful ulnar-sided peripheral tears are otherwise hard to diagnose. The diagnostic performance of MR imaging for interosseous ligament tears varies considerably. The sensitivity for scapholunate ligament tears is consistently better than for lunotriquetral ligament tears. Gadolinium-enhanced MR imaging is considered to be the best technique for detecting established avascularity of bone, but the assessment of the MR results remains challenging. Most cases of ulnar impaction syndrome have characteristic focal signal intensity changes in the ulnar aspect of the lunate. Avascular necrosis of the lunate (Kienboeck's disease) is characterized by signal changes starting in the proximal radial aspect of the lunate. MR imaging is extremely sensitive for occult fractures. Questions arise if occult posttraumatic bone lesions seen on MR images only necessarily require the same treatment as fractures evident on plain films or computed tomography (CT) images. MR imaging and ultrasound are equally effective for detecting occult carpal ganglia. Carpe bossu (carpal boss) is a bony protuberance of a carpometacarpal joint II and III which may be associated with pain. (orig.)

  15. Role of MR imaging in chronic wrist pain

    Energy Technology Data Exchange (ETDEWEB)

    Zanetti, Marco; Saupe, Nadja [University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); Nagy, Ladislav [University Hospital Balgrist, Department of Orthopedic Surgery, Zurich (Switzerland)

    2007-04-15

    Magnetic resonance (MR) imaging for chronic wrist pain is challenging. Correct assessment of the triangular fibrocartilage, hyaline cartilage, ligaments, and tendons has become mandatory for comprehensive decision making in wrist surgery. The MR technique, potential and limits of MR imaging in patients with chronic wrist pain will be discussed. MR arthrography with injection of gadolinium-containing contrast material into the distal radioulnar joint is suggested for evaluation of the triangular fibrocartilage. The clinically meaningful ulnar-sided peripheral tears are otherwise hard to diagnose. The diagnostic performance of MR imaging for interosseous ligament tears varies considerably. The sensitivity for scapholunate ligament tears is consistently better than for lunotriquetral ligament tears. Gadolinium-enhanced MR imaging is considered to be the best technique for detecting established avascularity of bone, but the assessment of the MR results remains challenging. Most cases of ulnar impaction syndrome have characteristic focal signal intensity changes in the ulnar aspect of the lunate. Avascular necrosis of the lunate (Kienboeck's disease) is characterized by signal changes starting in the proximal radial aspect of the lunate. MR imaging is extremely sensitive for occult fractures. Questions arise if occult posttraumatic bone lesions seen on MR images only necessarily require the same treatment as fractures evident on plain films or computed tomography (CT) images. MR imaging and ultrasound are equally effective for detecting occult carpal ganglia. Carpe bossu (carpal boss) is a bony protuberance of a carpometacarpal joint II and III which may be associated with pain. (orig.)

  16. The management of wrist injuries: an international perspective.

    Science.gov (United States)

    Garcia-Elias, Marc; Folgar, Miguel Angel Vidal

    2006-11-01

    Wrist injury is common and may significantly impair the overall function of the upper extremity unless properly managed. Fractures of the distal radius are particularly common among the aging population, accounting for nearly 1/6 of all fractures, often as a result of increased longevity with the subsequent underlying osteoporosis. New diagnostic tools, including wrist arthroscopy, magnetic resonance imaging, or computed tomography, are increasingly available in developed countries allowing accurate recognition and more effective resolution of lesions which would be otherwise missed using conventional methods. First world treatment standards, however, can scarcely be introduced in developing countries owing to, among other factors, different prevalence of problems, and the lack of resource to implement most modern technologies. If any program needs to be introduced that meets the demands of wrist injury management in the third world, aside from a better regionalisation of trauma care, it should emphasise adequate training of professionals in the use of more cost effective techniques of fracture reduction and stabilisation, applicable everywhere, with the minimum possible morbidity. PMID:17049527

  17. Methylene blue-enhanced arthroscopic resection of dorsal wrist ganglions.

    Science.gov (United States)

    Lee, Byung Joo; Sawyer, Gregory A; Dasilva, Manuel F

    2011-12-01

    The ganglion is the most common soft tissue mass of the hand and wrist. Over the past 10 to 15 years, there has been a growing interest in arthroscopic treatment of dorsal wrist ganglions. Proposed advantages of arthroscopy include greater motion (particularly wrist flexion), improved cosmesis, and potential to identify/treat other intra-articular pathology. Despite the documented clinical success of arthroscopic ganglion excision, limitations include inconsistent identification of the ganglion stalk. Our described technique offers a means by which to improve visualization of the ganglion stalk intra-articularly to produce a more effective and efficient arthroscopic ganglion excision. During the procedure, a small volume of methylene blue solution is injected into the cyst. Its communication with the joint is apparent arthroscopically, thus identifying the location of the stalk. With the ability to precisely identify the ganglion stalk using an injection of methylene blue, the surgeon can direct the arthroscopic debridement toward the appropriate pathologic tissue. Unnecessary debridement of uninvolved tissue can be avoided with the technique. This also allows for optimal portal placement and, in particular, indicates whether a midcarpal portal should be employed. This should result in fewer recurrences, decreased operative time, and less iatrogenic injury. PMID:22105637

  18. Prospective outcomes of arthroscopic treatment of dorsal wrist ganglia.

    Science.gov (United States)

    Aslani, Hamidreza; Najafi, Arvin; Zaaferani, Zohre

    2012-03-01

    The purpose of this study was to assess the results of arthroscopic resection of dorsal wrist ganglia. Between November 2002 and September 2007, all patients with dorsal wrist ganglia underwent arthroscopic resection in our institution. Average follow-up was 39.2 months (range, 24-71 months). Fifty-two patients (40 women and 12 men; mean age, 29.8 years) were treated with our operative technique. Symptoms at presentation were unpleasant appearance in 15 patients (28.8 %), pain in 30 (57.6%), and unpleasant appearance and pain in 7 (13.5%). The ganglion cyst site was in front of the midcarpal joint in 41 patients (78.8%), in front of the radiocarpal joint in 6 patients (11.5%), and in front of the radiocarpal and midcarpal joints in 5 patients (9.6%). Our surgical technique resulted in a significant improvement in flexion, extension, and grip strength (P≤.005). In patients with painful ganglia, treatment also had a significant effect. Nine (17.3%) recurrences were observed. Mean time off work was 14 days, but 19 patients returned to work immediately. According to the results of this study, we recommend the use of arthroscopy as the primary treatment method for dorsal wrist ganglion excision. PMID:22385448

  19. Occult scapholunate ganglion: a cause of dorsal radial wrist pain.

    Science.gov (United States)

    Steinberg, B D; Kleinman, W B

    1999-03-01

    There are multiple causes for chronic dorsal wrist pain over the scapholunate ligament, including occult dorsal carpal ganglion cyst, scaphoid impaction syndrome, dorsal carpal capsulitis, distal posterior interosseous nerve syndrome, and dynamic scapholunate ligament instability. Patients with such pain often have normal x-rays. A retrospective study of 21 patients undergoing surgical exploration for chronic dorsal radial wrist pain who had no palpable cyst and normal x-rays revealed that 18 of the patients had occult scapholunate ganglion cysts or myxomatous degeneration within the scapholunate ligament. All had failed long-term conservative management. Surgery involved an approach through Langer's lines, resection of a large triangular portion of the capsule between the dorsal intercarpal and radiotriquetral ligaments, and tangential debridement of the area of myxoid degeneration proximal to the distal 2 to 3 mm of dorsal scapholunate interosseous ligament. None of the patients had scapholunate instability or scaphoid impacting syndrome. Of the 18 patients with histologically confirmed myxomatous changes in the scapholunate ligament, 16 had an excellent outcome as defined by rigorous criteria; 1 had a good outcome. There was 1 patient with a poor result. A compelling argument is made for surgical exploration of the scapholunate joint in patients with persistent dorsal radial wrist pain and scapholunate point tenderness. PMID:10194003

  20. Maximum acceptable forces for repetitive ulnar deviation of the wrist.

    Science.gov (United States)

    Snook, S H; Vaillancourt, D R; Ciriello, V M; Webster, B S

    1997-07-01

    The purpose of this experiment was to quantify maximum acceptable forces for ulnar deviation motions of the wrist at various repetition rates. Subjects grasped a handle with a power grip and moved it through a 1.40 rad (80 degrees) ulnar deviation wrist motion (similar to a knife cutting task). A psychophysical methodology was used in which the subject adjusted the resistance on the handle and the experiment manipulated or controlled all other variables. Two series of experiments were conducted. Thirteen subjects completed the first series, which investigated repetition rates of 15 and 20 motions per minute. Eleven subjects completed the second series, which investigated 15, 20, and 25 motions per minute. Subjects performed for 7 hours per day, 5 days per week, for 4 weeks in the first series and 5 weeks in the second series. The subjects were instructed to work as if they were on an incentive basis, getting paid for the amount of work they performed. Symptoms were recorded by the subjects during the last 5 minutes of each hour. The results are presented and compared with maximum acceptable forces for wrist flexion and extension. PMID:9208467

  1. Magnetic resonance imaging of the wrist: Diagnostic performance statistics

    International Nuclear Information System (INIS)

    AIM: To review the published diagnostic performance statistics for magnetic resonance imaging (MRI) of the wrist for tears of the triangular fibrocartilage complex, the intrinsic carpal ligaments, and for osteonecrosis of the carpal bones. MATERIALS AND METHODS: We used Medline and Embase to search the English language literature. Studies evaluating the diagnostic performance of MRI of the wrist in living patients with surgical confirmation of MR findings were identified. RESULTS: We identified 11 studies reporting the diagnostic performance of MRI for tears of the triangular fibrocartilage complex for a total of 410 patients, six studies for the scapho-lunate ligament (159 patients), six studies for the luno-triquetral ligament (142 patients) and four studies (56 patients) for osteonecrosis of the carpal bones. CONCLUSIONS: Magnetic resonance imaging is an accurate means of diagnosing tears of the triangular fibrocartilage and carpal osteonecrosis. Although MRI is highly specific for tears of the intrinsic carpal ligaments, its sensitivity is low. The diagnostic performance of MRI in the wrist is improved by using high-resolution T2* weighted 3D gradient echo sequences. Using current imaging techniques without intra-articular contrast medium, magnetic resonance imaging cannot reliably exclude tears of the intrinsic carpal ligaments. Hobby, J.L. (2001)

  2. Functional outcome of patients undergoing replantation of hand at wrist level-7 year experience

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Mahajan

    2013-01-01

    Full Text Available Background: Replantation is defined as reattachment of amputated limb using neurovascular and musculoskeletal structures in order to obtain recovery of limb. Re-vascularisation involves all the above steps in case of limb injuries that result in a near total amputation. Aim and Objective : To study the functional outcome of patients undergoing replantation of hand at wrist level. Material and Methods: This is a retrospective study of patients who underwent replantation of total amputation of hand at wrist level within a period of Jan 2003-June 2010. We evaluated post operative functional outcome compared to uninjured hand taking into consideration: 1. The patient′s overall satisfaction with the hand. 2. Recovery of flexor and extensor function of thumb and fingers. 3. Recovery of thumb opposition. 4. Recovery of sensations in the median and ulnar nerve distribution. 5. Ability of surviving hand to perform daily tasks. Results: There were total seventeen patients and age range was two years to 55 years. Out of 17 patients,16 were males. All the replantations were successful except for one. Summary: The results showed that, although the replanted hands were never functionally as good as the contralateral hand the patients were able to perform most of the daily activities.

  3. Neurospora wc-1 and wc-2: transcription, photoresponses, and the origins of circadian rhythmicity.

    Science.gov (United States)

    Crosthwaite, S K; Dunlap, J C; Loros, J J

    1997-05-01

    Circadian rhythmicity is universally associated with the ability to perceive light, and the oscillators ("clocks") giving rise to these rhythms, which are feedback loops based on transcription and translation, are reset by light. Although such loops must contain elements of positive and negative regulation, the clock genes analyzed to date-frq in Neurospora and per and tim in Drosophila-are associated only with negative feedback and their biochemical functions are largely inferred. The white collar-1 and white collar-2 genes, both global regulators of photoresponses in Neurospora, encode DNA binding proteins that contain PAS domains and are believed to act as transcriptional activators. Data shown here suggest that wc-1 is a clock-associated gene and wc-2 is a clock component; both play essential roles in the assembly or operation of the Neurospora circadian oscillator. Thus DNA binding and transcriptional activation can now be associated with a clock gene that may provide a positive element in the feedback loop. In addition, similarities between the PAS-domain regions of molecules involved in light perception and circadian rhythmicity in several organisms suggest an evolutionary link between ancient photoreceptor proteins and more modern proteins required for circadian oscillation. PMID:9115195

  4. Interactions of polymorphisms in different clock genes associated with circadian phenotypes in humans

    Directory of Open Access Journals (Sweden)

    Mario Pedrazzoli

    2010-01-01

    Full Text Available Several studies have shown that mutations and polymorphisms in clock genes are associated with abnormal circadian parameters in humans and also with more subtle non-pathological phenotypes like chronotypes. However, there have been conflicting results, and none of these studies analyzed the combined effects of more than one clock gene. Up to date, association studies in humans have focused on the analysis of only one clock gene per study. Since these genes encode proteins that physically interact with each other, combinations of polymorphisms in different clock genes could have a synergistic or an inhibitory effect upon circadian phenotypes. In the present study, we analyzed the combined effects of four polymorphisms in four clock genes (Per2, Per3, Clock and Bmal1 in people with extreme diurnal preferences (morning or evening. We found that a specific combination of polymorphisms in these genes is more frequent in people who have a morning preference for activity and there is a different combination in individuals with an evening preference for activity. Taken together, these results show that it is possible to detect clock gene interactions associated with human circadian phenotypes and bring an innovative idea of building a clock gene variation map that may be applied to human circadian biology.

  5. Differential effect of lithium on the circadian oscillator in young and old hamsters

    International Nuclear Information System (INIS)

    Lithium is one of the most commonly used drugs in the prophylaxis and treatment of bipolar disorder. It is also known to lengthen circadian period in several organisms. Previously, we reported that there was the association between lengthening circadian period by lithium and GSK-3 protein and its enzyme activity in the mouse suprachiasmatic nucleus (SCN). In this study, we show that lithium affects the circadian oscillator in young and old hamster SCN, in an age-dependent manner. We found that basal levels of phosphorylated GSK-3 (pGSK-3) protein expression in old hamsters are much lower than that in young hamsters. Furthermore, in the old hamsters, lithium did not affect the period of the locomotor activity rhythm or pGSK-3 expression, while changing period and pGSK-3 in the younger animals. These results indicate that the content of pGSK-3 in the SCN has an important role in age-dependent effects of lithium on the circadian oscillator

  6. Effects of exposure to intermittent versus continuous red light on human circadian rhythms, melatonin suppression, and pupillary constriction.

    Science.gov (United States)

    Ho Mien, Ivan; Chua, Eric Chern-Pin; Lau, Pauline; Tan, Luuan-Chin; Lee, Ivan Tian-Guang; Yeo, Sing-Chen; Tan, Sara Shuhui; Gooley, Joshua J

    2014-01-01

    Exposure to light is a major determinant of sleep timing and hormonal rhythms. The role of retinal cones in regulating circadian physiology remains unclear, however, as most studies have used light exposures that also activate the photopigment melanopsin. Here, we tested the hypothesis that exposure to alternating red light and darkness can enhance circadian resetting responses in humans by repeatedly activating cone photoreceptors. In a between-subjects study, healthy volunteers (n = 24, 21-28 yr) lived individually in a laboratory for 6 consecutive days. Circadian rhythms of melatonin, cortisol, body temperature, and heart rate were assessed before and after exposure to 6 h of continuous red light (631 nm, 13 log photons cm(-2) s(-1)), intermittent red light (1 min on/off), or bright white light (2,500 lux) near the onset of nocturnal melatonin secretion (n = 8 in each group). Melatonin suppression and pupillary constriction were also assessed during light exposure. We found that circadian resetting responses were similar for exposure to continuous versus intermittent red light (P = 0.69), with an average phase delay shift of almost an hour. Surprisingly, 2 subjects who were exposed to red light exhibited circadian responses similar in magnitude to those who were exposed to bright white light. Red light also elicited prolonged pupillary constriction, but did not suppress melatonin levels. These findings suggest that, for red light stimuli outside the range of sensitivity for melanopsin, cone photoreceptors can mediate circadian phase resetting of physiologic rhythms in some individuals. Our results also show that sensitivity thresholds differ across non-visual light responses, suggesting that cones may contribute differentially to circadian resetting, melatonin suppression, and the pupillary light reflex during exposure to continuous light. PMID:24797245

  7. Validation of the IOF quality of life questionnaire for patients with wrist fracture

    OpenAIRE

    Lips, P.T.A.M.; Jameson, K; Bianchi, M. L.; Goemaere, S.; Boonen, S; Reeve, J.; Stepan, J.; Johnell, O.; Schoor, van der, R.; Dennison, E.; Kanis, J A; Cooper, C.

    2009-01-01

    INTRODUCTION: Wrist fracture causes pain and decreased physical, social and emotional function. The International Osteoporosis Foundation has developed a specific questionnaire to assess quality of life in patients with wrist fracture. This questionnaire, including 12 questions, was validated in a multicentre study and compared with an osteoporosis-specific questionnaire (Qualeffo-41) and a generic questionnaire (EQ-5D). METHODS: The study included 105 patients with a recent wrist fracture an...

  8. Joint Preservation of the Wrist Using Articulated Distraction Arthroplasty: A Case Report of a Novel Technique

    OpenAIRE

    Fletcher, Matt D.A.

    2015-01-01

    Distraction arthroplasty of the ankle, elbow, and hip has become widely accepted and used within the orthopaedic community with excellent initial results which appear sustained. To date it has not been applied to the wrist in the same manner. A novel technique, drawn upon past success of articulated ankle distraction and static wrist distraction, was devised and evaluated by application of articulated wrist distraction performed over a 12-week period in a patient with poor functional outcome ...

  9. Lightweight wrist photoplethysmography for heavy exercise: motion robust heart rate monitoring algorithm

    OpenAIRE

    Lai, Po-Hsiang; Kim, Insoo

    2015-01-01

    The challenge of heart rate monitoring based on wrist photoplethysmography (PPG) during heavy exercise is addressed. PPG is susceptible to motion artefacts, which have to be mitigated for accurate heart rate estimation. Motion artefacts are particularly apparent for wrist devices, for example, a smart watch, because of the high mobility of the arms. Proposed is a low complexity highly accurate heart rate estimation method for continuous heart rate monitoring using wrist PPG. The proposed meth...

  10. Ulnar-sided wrist pain. Part I: anatomy and physical examination

    International Nuclear Information System (INIS)

    Ulnar-sided wrist pain is a common complaint, and it presents a diagnostic challenge for hand surgeons and radiologists. The complex anatomy of this region, combined with the small size of structures and subtle imaging findings, compound this problem. A thorough understanding of ulnar-sided wrist anatomy and a systematic clinical examination of this region are essential in arriving at an accurate diagnosis. In part I of this review, ulnar-sided wrist anatomy and clinical examination are discussed for a more comprehensive understanding of ulnar-sided wrist pain. (orig.)

  11. Ulnar-sided wrist pain. Part I: anatomy and physical examination

    Energy Technology Data Exchange (ETDEWEB)

    Vezeridis, Peter S.; Blazar, Philip [Brigham and Women' s Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Yoshioka, Hiroshi [University of California, Irvine, Department of Radiological Sciences, Orange, CA (United States); Han, Roger [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States)

    2010-08-15

    Ulnar-sided wrist pain is a common complaint, and it presents a diagnostic challenge for hand surgeons and radiologists. The complex anatomy of this region, combined with the small size of structures and subtle imaging findings, compound this problem. A thorough understanding of ulnar-sided wrist anatomy and a systematic clinical examination of this region are essential in arriving at an accurate diagnosis. In part I of this review, ulnar-sided wrist anatomy and clinical examination are discussed for a more comprehensive understanding of ulnar-sided wrist pain. (orig.)

  12. A study comparing MRI with clinical examinations on wrists with rheumatoid arthritis

    International Nuclear Information System (INIS)

    Objective: To study the appearances of rheumatoid arthritis (RA) on MRI, and compare MRI with clinical examinations on wrists with RA. Methods: Fifty patients, fulfilled 1987 American Rheumatism Association (ARA) revised criteria, and 10 age-matched healthy controls entered the study. T1-weighted spin echo, short time inversion recovery (STIR) of both wrists, gadolinium contrast material-enhanced sequences of dominant wrists were performed in the coronal planes. MRl, plain wrist radiographs, clinical date, including swollen joint, patient global assessment (AIMS), and laboratory examinations including ESR, RF, APF, and AKA were obtained at the same time. Functional disability was assessed using the Health Assessment Questionnaire Disability Score. Results: In 50 patients, all had pannus on MRI of wrists, 38 patients had enhanced signal intensity for pannus, 21 patients had bone marrow edema, 37 patients had joint effusion, and 37 patients had bone erosions. There were significant difference in the ESR, HAQ, AIMS as well as swollen joint count between patients with bone marrow edema and patients without bone marrow edema (P2=5.06, P=0.025; χ2=5.59, P=0.018). Number of patients with MRI erosion of wrists was associated with the number of patients without MRI bone marrow edema of wrists (χ2=5.11, P=0.024). Conclusion: MRI can find the appearances of wrists with RA. Comparing MRI with clinical examinations on wrists with RA, authors can assess and evaluate the role of MRI on RA

  13. The use of routine wrist radiography is not useful in the evaluation of patients with a ganglion cyst of the wrist.

    Science.gov (United States)

    Wong, Andrew S; Jebson, Peter J L; Murray, Peter M; Trigg, Stephen D

    2007-09-01

    The purpose of this study was to evaluate the cost-effectiveness of routine wrist radiography in the evaluation of patients with a wrist ganglion. In the setting of a University-based hand surgery practice, 103 consecutive patients with a dorsal or volar wrist ganglion underwent posteroanterior, lateral, and oblique radiographs of the involved wrist. There were 24 men and 79 women with an average age of 34 years (range 4-67 years). A retrospective review of the medical records was performed. Abnormalities on plain radiographs were noted in only 13 patients (13%). Findings included six cases of thumb carpometacarpal joint arthritis and one case each of an enchondroma, congenital distal radioulnar joint (DRUJ) anomaly, DRUJ degenerative changes, intraosseous ganglion, carpal boss, radiocarpal arthritis, and thumb metacarpophalangeal joint osteoarthritis. In only one case (1%) did the findings alter the management. At our institution, the professional and technical charge for three views of the wrist is $172. This confers a cost of $17,716 per therapeutically significant finding in our series. We conclude that routinely performing wrist radiography is not cost-effective in the evaluation and treatment decision-making process in patients with a wrist ganglion. PMID:18780070

  14. The role of circadian rhythm in breast cancer

    Science.gov (United States)

    Li, Shujing; Ao, Xiang

    2013-01-01

    The circadian rhythm is an endogenous time keeping system shared by most organisms. The circadian clock is comprised of both peripheral oscillators in most organ tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN) of the central nervous system. The circadian rhythm is crucial in maintaining the normal physiology of the organism including, but not limited to, cell proliferation, cell cycle progression, and cellular metabolism; whereas disruption of the circadian rhythm is closely related to multi-tumorigenesis. In the past several years, studies from different fields have revealed that the genetic or functional disruption of the molecular circadian rhythm has been found in various cancers, such as breast, prostate, and ovarian. In this review, we will investigate and present an overview of the current research on the influence of circadian rhythm regulating proteins on breast cancer. PMID:23997531

  15. Mechanisms by which circadian rhythm disruption may lead to cancer

    Directory of Open Access Journals (Sweden)

    L. C. Roden

    2010-02-01

    Full Text Available Humans have evolved in a rhythmic environment and display daily (circadian rhythms in physiology, metabolism and behaviour that are in synchrony with the solar day. Modern lifestyles have compromised the exposure to bright light during the day and dark nights, resulting in the desynchronisation of endogenously generated circadian rhythms from the external environment and loss of coordination between rhythms within the body. This has detrimental effects on physical and mental health, due to the misregulation and uncoupling of important cellular and physiological processes. Long-term shift workers who are exposed to bright light at night experience the greatest disruption of their circadian rhythms. Studies have shown an association between exposure to light at night, circadian rhythm disruption and an increased risk of cancer. Previous reviews have explored the relevance of light and melatonin in cancer, but here we explore the correlation of circadian rhythm disruption and cancer in terms of molecular mechanisms affecting circadian gene expression and melatonin secretion.

  16. Proteomics of the photoneuroendocrine circadian system of the brain

    DEFF Research Database (Denmark)

    Møller, Morten; Lund-Andersen, Casper; Rovsing, Louise;

    2010-01-01

    The photoneuroendocrine circadian system of the brain consists of (a) specialized photoreceptors in the retina, (b) a circadian generator located in the forebrain that contains "clock genes," (c) specialized nuclei in the forebrain involved in neuroendocrine secretion, and (d) the pineal gland. The...... circadian generator is a nucleus, called the suprachiasmatic nucleus (SCN). The neurons of this nucleus contain "clock genes," the transcription of which exhibits a circadian rhythm. Most circadian rhythms are generated by the neurons of this nucleus and, via neuronal and humoral connections, the SCN......-generating system in mammals is described, and recent proteomic studies that investigate day/night changes in the retina, SCN, and pineal gland are reviewed. Further circadian changes controlled by the SCN in gene and protein expression in the liver are discussed....

  17. The harmala alkaloid harmine is a modulator of circadian Bmal1 transcription.

    Science.gov (United States)

    Onishi, Yoshiaki; Oishi, Katsutaka; Kawano, Yasuhiro; Yamazaki, Yoshimitsu

    2012-02-01

    Biological rhythms are orchestrated by a cell-autonomous clock system that drives the rhythmic cascade of clock genes. We established an assay system using NIH 3T3 cells stably expressing the Bmal1 promoter-driven luciferase reporter gene and used it to analyse circadian oscillation of the gene. Modulators of PKC (protein kinase C) revealed that an activator and an inhibitor represented short- and long-period phenotypes respectively which were consistent with reported effects of PKC on the circadian clock and validated the assay system. We examined the effects of the alkaloid harmine, contained in Hoasca, which has a wide spectrum of pharmacological actions, on circadian rhythms using the validated assay system. Harmine dose dependently elongated the period. Furthermore, EMSA (electrophoretic mobility-shift assay) and Western-blot analysis showed that harmine enhanced the transactivating function of RORα (retinoid-related orphan receptor α), probably by increasing its nuclear translocation. Exogenous expression of RORα also caused a long period, confirming the phenotype indicated by harmine. These results suggest that harmine extends the circadian period by enhancing RORα function and that harmine is a new candidate that contributes to the control of period length in mammalian cells. PMID:21401525

  18. PI3K regulates BMAL1/CLOCK-mediated circadian transcription from the Dbp promoter.

    Science.gov (United States)

    Morishita, Yoshikazu; Miura, Daiki; Kida, Satoshi

    2016-06-01

    The circadian rhythm generated by circadian clock underlies a molecular mechanism of rhythmic transcriptional regulation by transcription factor BMAL1/CLOCK. Importantly, the circadian clock is coordinated by exogenous cues to accommodate to changes in the external environment. However, the molecular mechanisms by which intracellular-signaling pathways mediate the adjustments of the circadian transcriptional rhythms remain unclear. In this study, we found that pharmacological inhibition or shRNA-mediated knockdown of phosphatidylinositol 3-kinase (PI3K) blocked upregulation of Dbp mRNA induced by serum shock in NIH 3T3 cells. Moreover, the inhibition of PI3K significantly reduced the promoter activity of the Dbp gene, as well as decreased the recruitment of BMAL1/CLOCK to the E-box in the Dbp promoter. Interestingly, the inhibition of PI3K blocked heterodimerization of BMAL1 and CLOCK. Our findings suggest that PI3K signaling plays a modulatory role in the regulation of the transcriptional rhythm of the Dbp gene by targeting BMAL1 and CLOCK. PMID:27022680

  19. Circadian desynchrony promotes metabolic disruption in a mouse model of shiftwork.

    Directory of Open Access Journals (Sweden)

    Johanna L Barclay

    Full Text Available Shiftwork is associated with adverse metabolic pathophysiology, and the rising incidence of shiftwork in modern societies is thought to contribute to the worldwide increase in obesity and metabolic syndrome. The underlying mechanisms are largely unknown, but may involve direct physiological effects of nocturnal light exposure, or indirect consequences of perturbed endogenous circadian clocks. This study employs a two-week paradigm in mice to model the early molecular and physiological effects of shiftwork. Two weeks of timed sleep restriction has moderate effects on diurnal activity patterns, feeding behavior, and clock gene regulation in the circadian pacemaker of the suprachiasmatic nucleus. In contrast, microarray analyses reveal global disruption of diurnal liver transcriptome rhythms, enriched for pathways involved in glucose and lipid metabolism and correlating with first indications of altered metabolism. Although altered food timing itself is not sufficient to provoke these effects, stabilizing peripheral clocks by timed food access can restore molecular rhythms and metabolic function under sleep restriction conditions. This study suggests that peripheral circadian desynchrony marks an early event in the metabolic disruption associated with chronic shiftwork. Thus, strengthening the peripheral circadian system by minimizing food intake during night shifts may counteract the adverse physiological consequences frequently observed in human shift workers.

  20. Newly Described Components and Regulatory Mechanisms of Circadian Clock Function in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Manuel Adrián Troncoso-Ponce; Paloma Mas

    2012-01-01

    The circadian clock temporally coordinates plant growth and metabolism in close synchronization with the diurnal and seasonal environmental changes.Research over the last decade has identified a number of clock components and a variety of regulatory mechanisms responsible for the rhythmic oscillations in metabolic and physiological activities.At the core of the clock,transcriptional/translational feedback loops modulate the expression of a significant proportion of the genome.In this article,we briefly describe some of the very recent advances that have improved our understanding of clock organization and function in Arabidopsis thaliana.The new studies illustrate the role of clock protein complex formation on circadian gating of plant growth and identify alternative splicing as a new regulatory mechanism for clock function.Examination of key clock properties such as temperature compensation has also opened new avenues for functional research within the plant clockwork.The emerging connections between the circadian clock and metabolism,hormone signaling and response to biotic and abiotic stress also add new layers of complexity to the clock network and underscore the significance of the circadian clock regulating the daily life of plants.

  1. Functional analysis of Casein Kinase 1 in a minimal circadian system.

    Directory of Open Access Journals (Sweden)

    Gerben van Ooijen

    Full Text Available The Earth's rotation has driven the evolution of cellular circadian clocks to facilitate anticipation of the solar cycle. Some evidence for timekeeping mechanism conserved from early unicellular life through to modern organisms was recently identified, but the components of this oscillator are currently unknown. Although very few clock components appear to be shared across higher species, Casein Kinase 1 (CK1 is known to affect timekeeping across metazoans and fungi, but has not previously been implicated in the circadian clock in the plant kingdom. We now show that modulation of CK1 function lengthens circadian rhythms in Ostreococcustauri, a unicellular marine algal species at the base of the green lineage, separated from humans by ~1.5 billion years of evolution. CK1 contributes to timekeeping in a phase-dependent manner, indicating clock-mediated gating of CK1 activity. Label-free proteomic analyses upon overexpression as well as inhibition revealed CK1-responsive phosphorylation events on a set of target proteins, including highly conserved potentially clock-relevant cellular regulator proteins. These results have major implications for our understanding of cellular timekeeping and can inform future studies in any circadian organism.

  2. Disrupted Circadian Rhythm as a Common Player in Developmental Models of Neuropsychiatric Disorders.

    Science.gov (United States)

    Marco, Eva M; Velarde, Elena; Llorente, Ricardo; Laviola, Giovanni

    2016-01-01

    The environment in which individuals develop and mature is critical for their physiological and psychological outcome; in particular, the intrauterine environment has reached far more clinical relevance given its potential influence on shaping brain function and thus mental health. Gestational stress and/or maternal infection during pregnancy has been related with an increased incidence of neuropsychiatric disorders, including depression and schizophrenia. In this framework, the use of animal models has allowed a formal and deep investigation of causal determinants. Despite disruption of circadian clocks often represents a hallmark of several neuropsychiatric disorders, the relationship between disruption of brain development and the circadian system has been scarcely investigated. Nowadays, there is an increasing amount of studies suggesting a link between circadian system malfunction, early-life insults and the appearance of neuropsychiatric diseases at adulthood. Here, we briefly review evidence from clinical literature and animal models suggesting that the exposure to prenatal insults, i.e. severe gestational stress or maternal immune activation, changes the foetal hormonal milieu increasing the circulating levels of both glucocorticoids and pro-inflammatory cytokines. These two biological events have been reported to affect genes expression in experimental models and critically interfere with brain development triggering and/or exacerbating behavioural anomalies in the offspring. Herein, we highlight the importance to unravel the individual components of the body circadian system that might also be altered by prenatal insults and that may be causally associated with the disruption of neural and endocrine developmental programming. PMID:26728169

  3. CT-based three-dimensional kinematic comparison of dart-throwing motion between wrists with malunited distal radius and contralateral normal wrists

    International Nuclear Information System (INIS)

    Aim: To compare motion of the capitate, scaphoid, and lunate in wrists with a malunited distal radius and contralateral normal wrists during dart-throwing motion (DTM) by three-dimensional kinematic studies using computed tomography (CT) images. Materials and methods: CT was performed simultaneously on both wrists in six patients with a unilateral distal radius malunion at three stepwise positions simulating DTM. Using volume registration technique, the kinematic variables of helical axis motion of the capitate, scaphoid, and lunate were calculated and compared between both wrists. The helical motion of the capitate was also evaluated in a scaphoid- and lunate-based coordinate system. Results: Among the average rotation and translation of the scaphoid, lunate, and capitate during DTM, only the average rotation of the capitate was significantly different between the uninjured (88.9°) and the injured (70°) wrist (p = 0.0075). Rotation of the capitate relative to the scaphoid (26.3° versus 37.8°, p = 0.029) or lunate (39.2° versus 59.3°, p = 0.028) was smaller in the malunited wrist. The centres of helical axis motion of the three carpal bones were located more dorsally and radially in the injured wrist. Conclusions: The present study showed that decreased DTM in wrists with a distal radius malunion resulted from decreased midcarpal motion. The present study of the capitate, scaphoid, and lunate in wrists with distal radius malunion might be the first to present a 3D kinematic analysis of the effect of distal radius malunion on the carpal bones

  4. Postnatal constant light compensates Cryptochrome1 and 2 double deficiency for disruption of circadian behavioral rhythms in mice under constant dark.

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    Daisuke Ono

    Full Text Available Clock genes Cryptochrome (Cry1 and Cry2 are essential for expression of circadian rhythms in mice under constant darkness (DD. However, circadian rhythms in clock gene Per1 expression or clock protein PER2 are detected in the cultured suprachiasmatic nucleus (SCN of neonatal Cry1 and Cry2 double deficient (Cry1 (-/-/Cry2 (-/- mice. A lack of circadian rhythms in adult Cry1 (-/-/Cry2 (-/- mice is most likely due to developmentally disorganized cellular coupling of oscillating neurons in the SCN. On the other hand, neonatal rats exposed to constant light (LL developed a tenable circadian system under prolonged LL which was known to fragment circadian behavioral rhythms. In the present study, Cry1 (-/-/Cry2 (-/- mice were raised under LL from postnatal day 1 for 7 weeks and subsequently exposed to DD for 3 weeks. Spontaneous movement was monitored continuously after weaning and PER2::LUC was measured in the cultured SCN obtained from mice under prolonged DD. Surprisingly, Chi square periodogram analysis revealed significant circadian rhythms of spontaneous movement in the LL-raised Cry1 (-/-/Cry2 (-/- mice, but failed to detect the rhythms in Cry1 (-/-/Cry2 (-/- mice raised under light-dark cycles (LD. By contrast, prolonged LL in adulthood did not rescue the circadian behavioral rhythms in the LD raised Cry1 (-/-/Cry2 (-/- mice. Visual inspection disclosed two distinct activity components with different periods in behavioral rhythms of the LL-raised Cry1(-/-/Cry2(-/- mice under DD: one was shorter and the other was longer than 24 hours. The two components repeatedly merged and separated. The patterns resembled the split behavioral rhythms of wild type mice under prolonged LL. In addition, circadian rhythms in PER2::LUC were detected in some of the LL-raised Cry1(-/-/Cry2(-/- mice under DD. These results indicate that neonatal exposure to LL compensates the CRY double deficiency for the disruption of circadian behavioral rhythms under DD in

  5. Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age

    International Nuclear Information System (INIS)

    Highlights: • 24 month old rats were supplemented with 0.2% lipoic acid in the diet for 2 weeks. • Lipoic acid shifts phase of core circadian clock proteins. • Lipoic acid corrects age-induced desynchronized lipid metabolism rhythms. - Abstract: It is well established that lipid metabolism is controlled, in part, by circadian clocks. However, circadian clocks lose temporal precision with age and correlates with elevated incidence in dyslipidemia and metabolic syndrome in older adults. Because our lab has shown that lipoic acid (LA) improves lipid homeostasis in aged animals, we hypothesized that LA affects the circadian clock to achieve these results. We fed 24 month old male F344 rats a diet supplemented with 0.2% (w/w) LA for 2 weeks prior to sacrifice and quantified hepatic circadian clock protein levels and clock-controlled lipid metabolic enzymes. LA treatment caused a significant phase-shift in the expression patterns of the circadian clock proteins Period (Per) 2, Brain and Muscle Arnt-Like1 (BMAL1), and Reverse Erythroblastosis virus (Rev-erb) β without altering the amplitude of protein levels during the light phase of the day. LA also significantly altered the oscillatory patterns of clock-controlled proteins associated with lipid metabolism. The level of peroxisome proliferator-activated receptor (PPAR) α was significantly increased and acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) were both significantly reduced, suggesting that the LA-supplemented aged animals are in a catabolic state. We conclude that LA remediates some of the dyslipidemic processes associated with advanced age, and this mechanism may be at least partially through entrainment of circadian clocks

  6. Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Dove; Finlay, Liam; Butler, Judy [Linus Pauling Institute, Oregon State University (United States); Gómez, Luis; Smith, Eric [Linus Pauling Institute, Oregon State University (United States); Biochemistry Biophysics Department, Oregon State University (United States); Moreau, Régis [Linus Pauling Institute, Oregon State University (United States); Hagen, Tory, E-mail: Tory.Hagen@oregonstate.edu [Linus Pauling Institute, Oregon State University (United States); Biochemistry Biophysics Department, Oregon State University (United States)

    2014-07-18

    Highlights: • 24 month old rats were supplemented with 0.2% lipoic acid in the diet for 2 weeks. • Lipoic acid shifts phase of core circadian clock proteins. • Lipoic acid corrects age-induced desynchronized lipid metabolism rhythms. - Abstract: It is well established that lipid metabolism is controlled, in part, by circadian clocks. However, circadian clocks lose temporal precision with age and correlates with elevated incidence in dyslipidemia and metabolic syndrome in older adults. Because our lab has shown that lipoic acid (LA) improves lipid homeostasis in aged animals, we hypothesized that LA affects the circadian clock to achieve these results. We fed 24 month old male F344 rats a diet supplemented with 0.2% (w/w) LA for 2 weeks prior to sacrifice and quantified hepatic circadian clock protein levels and clock-controlled lipid metabolic enzymes. LA treatment caused a significant phase-shift in the expression patterns of the circadian clock proteins Period (Per) 2, Brain and Muscle Arnt-Like1 (BMAL1), and Reverse Erythroblastosis virus (Rev-erb) β without altering the amplitude of protein levels during the light phase of the day. LA also significantly altered the oscillatory patterns of clock-controlled proteins associated with lipid metabolism. The level of peroxisome proliferator-activated receptor (PPAR) α was significantly increased and acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) were both significantly reduced, suggesting that the LA-supplemented aged animals are in a catabolic state. We conclude that LA remediates some of the dyslipidemic processes associated with advanced age, and this mechanism may be at least partially through entrainment of circadian clocks.

  7. A Novel Bmal1 Mutant Mouse Reveals Essential Roles of the C-Terminal Domain on Circadian Rhythms.

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    Noheon Park

    Full Text Available The mammalian circadian clock is an endogenous biological timer comprised of transcriptional/translational feedback loops of clock genes. Bmal1 encodes an indispensable transcription factor for the generation of circadian rhythms. Here, we report a new circadian mutant mouse from gene-trapped embryonic stem cells harboring a C-terminus truncated Bmal1 (Bmal1GTΔC allele. The homozygous mutant (Bmal1GTΔC/GTΔC mice immediately lost circadian behavioral rhythms under constant darkness. The heterozygous (Bmal1+/GTΔC mice displayed a gradual loss of rhythms, in contrast to Bmal1+/- mice where rhythms were sustained. Bmal1GTΔC/GTΔC mice also showed arrhythmic mRNA and protein expression in the SCN and liver. Lack of circadian reporter oscillation was also observed in cultured fibroblast cells, indicating that the arrhythmicity of Bmal1GTΔC/GTΔC mice resulted from impaired molecular clock machinery. Expression of clock genes exhibited distinct responses to the mutant allele in Bmal1+/GTΔC and Bmal1GTΔC/GTΔC mice. Despite normal cellular localization and heterodimerization with CLOCK, overexpressed BMAL1GTΔC was unable to activate transcription of Per1 promoter and BMAL1-dependent CLOCK degradation. These results indicate that the C-terminal region of Bmal1 has pivotal roles in the regulation of circadian rhythms and the Bmal1GTΔC mice constitute a novel model system to evaluate circadian functional mechanism of BMAL1.

  8. Circadian genes differentially affect tolerance to ethanol in Drosophila

    Science.gov (United States)

    Pohl, Jascha B.; Ghezzi, Alfredo; Lew, Linda K.; Robles, Roseanna B.; Cormack, Lawrence; Atkinson, Nigel S.

    2016-01-01

    Background There is a strong relationship between circadian rhythms and ethanol responses. Ethanol consumption has been shown to disrupt physiological and behavioral circadian rhythms in mammals (Spanagel et al., 2005b). The Drosophila central circadian pacemaker is composed of proteins encoded by the per, tim, cyc, and Clk genes. Using Drosophila mutant analysis we asked whether these central components of the circadian clock make the equivalent contribution towards ethanol tolerance and whether rhythmicity itself is necessary for tolerance. Methods We tested flies carrying mutations in core clock genes for the capacity to acquire ethanol tolerance. Tolerance was assayed by comparing the sedation curves of populations during their first and second sedation. Animals that had acquired tolerance sedated more slowly. Movement was also monitored as the flies breathe the ethanol vapor to determine if other facets of the ethanol response were affected by the mutations. Gas chromatography was used to measure internal ethanol concentration. Constant light was used to non-genetically destabilize the PER and TIM proteins. Results A group of circadian mutations, all of which eliminate circadian rhythms, do not disrupt tolerance identically. Mutations in per, tim, and cyc completely block tolerance. However, a mutation in Clk does not interfere with tolerance. Constant light also disrupts the capacity to acquire tolerance. These lines did not differ in ethanol absorption. Conclusions Mutations affecting different parts of the intracellular circadian clock can block the capacity to acquire rapid ethanol tolerance. However, the role of circadian genes in ethanol tolerance is independent of their role in producing circadian rhythmicity. The interference in the capacity to acquire ethanol tolerance by some circadian mutations is not merely a downstream effect of a nonfunctional circadian clock, instead these circadian genes play an independent role in ethanol tolerance. PMID

  9. Circadian Rhythms, the Molecular Clock, and Skeletal Muscle

    OpenAIRE

    Lefta, Mellani; Wolff, Gretchen; Esser, Karyn A

    2011-01-01

    Almost all organisms ranging from single cell bacteria to humans exhibit a variety of behavioral, physiological, and biochemical rhythms. In mammals, circadian rhythms control the timing of many physiological processes over a 24-h period, including sleep-wake cycles, body temperature, feeding, and hormone production. This body of research has led to defined characteristics of circadian rhythms based on period length, phase, and amplitude. Underlying circadian behaviors is a molecular clock me...

  10. Circadian Organization of Behavior and Physiology in Drosophila

    OpenAIRE

    Allada, Ravi; Chung, Brian Y.

    2010-01-01

    Circadian clocks organize behavior and physiology to adapt to daily environmental cycles. Genetic approaches in the fruit fly, Drosophila melanogaster, have revealed widely conserved molecular gears of these 24-h timers. Yet much less is known about how these cell-autonomous clocks confer temporal information to modulate cellular functions. Here we discuss our current knowledge of circadian clock function in Drosophila, providing an overview of the molecular underpinnings of circadian clocks....

  11. A role for the circadian genes in drug addiction

    OpenAIRE

    Falcón, Edgardo; McClung, Colleen A.

    2008-01-01

    Diurnal and circadian rhythms are prominent in nearly all bodily functions. Chronic disruptions in normal sleep wake and social schedules can lead to serious health problems such as those seen in shift worker’s syndrome. Moreover, genetic disruptions in normal circadian gene functions have recently been linked to a variety of psychiatric conditions including depression, bipolar disorder, seasonal affective disorder and alcoholism. Recent studies are beginning to determine how these circadian ...

  12. A Clinical Approach to Circadian Rhythm Sleep Disorders

    OpenAIRE

    Barion, Ana; Zee, Phyllis C.

    2007-01-01

    Circadian rhythm sleep disorders are characterized by complaints of insomnia and excessive sleepiness that are primarily due to alterations in the internal circadian timing system or a misalignment between the timing of sleep and the 24-hour social and physical environment. In addition to physiological and environmental factors, maladaptive behaviors often play an important role in the development of many of the circadian rhythm sleep disorders. This review will focus on the clinical approach...

  13. AMPK at the crossroads of circadian clocks and metabolism

    OpenAIRE

    Jordan, Sabine D.; Lamia, Katja A.

    2012-01-01

    Circadian clocks coordinate behavior and physiology with daily environmental cycles and thereby optimize the timing of metabolic processes such as glucose production and insulin secretion. Such circadian regulation of metabolism provides an adaptive advantage in diverse organisms. Mammalian clocks are primarily based on a transcription and translation feedback loop in which a heterodimeric complex of the transcription factors CLOCK (circadian locomotor output cycles kaput) and BMAL1 (brain an...

  14. Anatomical peculiarities of sensory tracts of the wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect

    Institute of Scientific and Technical Information of China (English)

    Sixin Ouyang; Zhenshan Peng; Jianguo Tan; Tianhong Peng; Jianzhong Xiao

    2006-01-01

    BACKGROUND: Translocation or transplantation of nerve stem has good effect;however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator.OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility.DESIGN: Duplicated and measured design.SETTING: Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris longus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve.MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect.RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non

  15. Pathophysiology and pathogenesis of circadian rhythm sleep disorders

    Directory of Open Access Journals (Sweden)

    Hida Akiko

    2012-03-01

    Full Text Available Abstract Metabolic, physiological and behavioral processes exhibit 24-hour rhythms in most organisms, including humans. These rhythms are driven by a system of self-sustained clocks and are entrained by environmental cues such as light-dark cycles as well as food intake. In mammals, the circadian clock system is hierarchically organized such that the master clock in the suprachiasmatic nuclei of the hypothalamus integrates environmental information and synchronizes the phase of oscillators in peripheral tissues. The transcription and translation feedback loops of multiple clock genes are involved in the molecular mechanism of the circadian system. Disturbed circadian rhythms are known to be closely related to many diseases, including sleep disorders. Advanced sleep phase type, delayed sleep phase type and nonentrained type of circadian rhythm sleep disorders (CRSDs are thought to result from disorganization of the circadian system. Evaluation of circadian phenotypes is indispensable to understanding the pathophysiology of CRSD. It is laborious and costly to assess an individual's circadian properties precisely, however, because the subject is usually required to stay in a laboratory environment free from external cues and masking effects for a minimum of several weeks. More convenient measurements of circadian rhythms are therefore needed to reduce patients' burden. In this review, we discuss the pathophysiology and pathogenesis of CRSD as well as surrogate measurements for assessing an individual's circadian phenotype.

  16. Circadian rhythms and addiction: mechanistic insights and future directions.

    Science.gov (United States)

    Logan, Ryan W; Williams, Wilbur P; McClung, Colleen A

    2014-06-01

    Circadian rhythms are prominent in many physiological and behavioral functions. Circadian disruptions either by environmental or molecular perturbation can have profound health consequences, including the development and progression of addiction. Both animal and humans studies indicate extensive bidirectional relationships between the circadian system and drugs of abuse. Addicted individuals display disrupted rhythms, and chronic disruption or particular chronotypes may increase the risk for substance abuse and relapse. Moreover, polymorphisms in circadian genes and an evening chronotype have been linked to mood and addiction disorders, and recent efforts suggest an association with the function of reward neurocircuitry. Animal studies are beginning to determine how altered circadian gene function results in drug-induced neuroplasticity and behaviors. Many studies suggest a critical role for circadian rhythms in reward-related pathways in the brain and indicate that drugs of abuse directly affect the central circadian pacemaker. In this review, we highlight key findings demonstrating the importance of circadian rhythms in addiction and how future studies will reveal important mechanistic insights into the involvement of circadian rhythms in drug addiction. PMID:24731209

  17. Circadian Clocks as Modulators of Metabolic Comorbidity in Psychiatric Disorders.

    Science.gov (United States)

    Barandas, Rita; Landgraf, Dominic; McCarthy, Michael J; Welsh, David K

    2015-12-01

    Psychiatric disorders such as schizophrenia, bipolar disorder, and major depressive disorder are often accompanied by metabolic dysfunction symptoms, including obesity and diabetes. Since the circadian system controls important brain systems that regulate affective, cognitive, and metabolic functions, and neuropsychiatric and metabolic diseases are often correlated with disturbances of circadian rhythms, we hypothesize that dysregulation of circadian clocks plays a central role in metabolic comorbidity in psychiatric disorders. In this review paper, we highlight the role of circadian clocks in glucocorticoid, dopamine, and orexin/melanin-concentrating hormone systems and describe how a dysfunction of these clocks may contribute to the simultaneous development of psychiatric and metabolic symptoms. PMID:26483181

  18. Circadian variation in the pharmacokinetics of verapamil

    DEFF Research Database (Denmark)

    Jespersen, C M; Frederiksen, M; Hansen, J F;

    1989-01-01

    Circadian variation in the metabolism of verapamil was investigated in 10 patients with stable angina pectoris during treatment with sustained-release verapamil 360 mg at 08.00 h or 22.0 h. No major difference in exercise parameters was found. During the evening dosage schedule a significantly...... greater bioavailability (AUC) and a prolonged time to peak concentration was found. During the night (24.00 h-06.00 h) the half-life of verapamil was significantly longer than during the day (16.00 h-22.00 h). These differences in pharmacokinetics may be due to reduced hepatic blood flow at night...... or to circadian variation in hepatic microsomal metabolism....

  19. Central Circadian Control of Female Reproductive Function

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    BrookeHMiller

    2014-01-01

    Full Text Available Over the past two decades, it has become clear just how much of our physiology is under the control of the suprachiasmatic nucleus (SCN and the cell-intrinsic molecular clock that ticks with a periodicity of approximately 24 hours. The SCN prepares our digestive system for meals, our adrenal axis for the stress of waking up in the morning, and the genes expressed in our muscles when we prepare to exercise, Long before molecular studies of genes such as Clock, Bmal1, and the Per homologs were possible, it was obvious that female reproductive function was under strict circadian control at every level of the hypothalamic-pituitary-gonadal (HPG axis, and in the establishment and successful maintenance of pregnancy. This review highlights our current understanding of the role that the SCN plays in regulating female reproductive physiology, with a special emphasis on the advances made possible through the use of circadian mutant mice.

  20. Circadian rhythm and cell population growth

    CERN Document Server

    Clairambault, Jean; Lepoutre, Thomas

    2010-01-01

    Molecular circadian clocks, that are found in all nucleated cells of mammals, are known to dictate rhythms of approximately 24 hours (circa diem) to many physiological processes. This includes metabolism (e.g., temperature, hormonal blood levels) and cell proliferation. It has been observed in tumor-bearing laboratory rodents that a severe disruption of these physiological rhythms results in accelerated tumor growth. The question of accurately representing the control exerted by circadian clocks on healthy and tumour tissue proliferation to explain this phenomenon has given rise to mathematical developments, which we review. The main goal of these previous works was to examine the influence of a periodic control on the cell division cycle in physiologically structured cell populations, comparing the effects of periodic control with no control, and of different periodic controls between them. We state here a general convexity result that may give a theoretical justification to the concept of cancer chronothera...