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  1. Content type: Research

    Nitric oxide synthase (NOS) is essential for the synthesis of nitric oxide (NO), a non-conventional neurotransmitter with an important role in synaptic plasticity underlying processes of hippocampus-dependent ...

    Authors: Aline V Machado-Nils, Larissa OM de Faria, André S Vieira, Simone A Teixeira, Marcelo N Muscará and Elenice AM Ferrari

    Citation: Journal of Circadian Rhythms 2013 11:12

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  2. Content type: Research

    Mammals can adapt to changing light/dark conditions by advancing or delaying their circadian clock phase. Light pulses evoke changes in gene expression and neuronal activity in the suprachiasmatic nuclei (SCN)...

    Authors: Marie Aramendy, Sascha Seibert, Philipp Treppmann, Karin Richter, Gudrun Ahnert-Hilger and Urs Albrecht

    Citation: Journal of Circadian Rhythms 2013 11:11

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  3. Content type: Research

    Although out-of-lab investigation of the human circadian clock at the clock gene expression level remains difficult, a recent method using hair follicle cells might be useful. While exercise may function as an...

    Authors: Akihiko Okamoto, Takuro Yamamoto, Ritsuko Matsumura, Koichi Node and Makoto Akashi

    Citation: Journal of Circadian Rhythms 2013 11:10

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  4. Content type: Research

    Our recent studies demonstrate that the murine homolog of the human tumor suppressor promyelocytic leukemia (PML) regulates circadian behavior of mice. To further gather insight into PML’s contribution to circ...

    Authors: Takao Miki, Misty Chen-Goodspeed, Zhaoyang Zhao and Cheng Chi Lee

    Citation: Journal of Circadian Rhythms 2013 11:9

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  5. Content type: Research

    Intracellular calcium is a biochemical messenger that regulates part of the metabolic adaptations in the daily fed-fast cycle. The aim of this study was to characterize the 24-h variations of the liver ryanodi...

    Authors: Adrián Báez-Ruiz, Karina Cázares-Gómez, Olivia Vázquez-Martínez, Raúl Aguilar-Roblero and Mauricio Díaz-Muñoz

    Citation: Journal of Circadian Rhythms 2013 11:8

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  6. Content type: Research

    Epidemiological studies in Japan have documented an association between morning type and a tryptophan-rich breakfast followed by exposure to sunlight in children. The association may be mediated by enhanced me...

    Authors: Kai Wada, Shota Yata, Osami Akimitsu, Milada Krejci, Teruki Noji, Miyo Nakade, Hitomi Takeuchi and Tetsuo Harada

    Citation: Journal of Circadian Rhythms 2013 11:4

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  7. Content type: Research

    There are several indications that malfunctions of the circadian clock contribute to depression. To search for particular circadian gene polymorphisms associated with depression, diverse polymorphisms were gen...

    Authors: Daniel F Kripke, Caroline M Nievergelt, Gregory J Tranah, Sarah S Murray, Katharine M Rex, Alexandra P Grizas, Elizabeth K Hahn, Heon-Jeong Lee, John R Kelsoe and Lawrence E Kline

    Citation: Journal of Circadian Rhythms 2013 11:3

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  8. Content type: Research

    The relation between circadian dysregulation and cancer incidence and progression has become a topic of major interest over the last decade. Also, circadian timing has gained attention regarding the use of chr...

    Authors: Natalia Paladino, José M Duhart, Malena L Mul Fedele and Diego A Golombek

    Citation: Journal of Circadian Rhythms 2013 11:2

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  9. Content type: Research

    A comprehensive understanding of the equine circadian clock involves the evaluation of circadian clock gene expression. A non-invasive and effective method for detecting equine clock gene expression has yet to...

    Authors: Lisa M Watts, John A Browne and Barbara A Murphy

    Citation: Journal of Circadian Rhythms 2012 10:7

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  10. Content type: Research

    An endogenous circadian clock controls locomotor activity in common spiny mice (Acomys cahirinus). However, little is known about the effects of constant light (LL) on this activity or about the existence of a...

    Authors: Christopher C Chabot, Devin M Connolly and Brenda B Waring

    Citation: Journal of Circadian Rhythms 2012 10:6

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  11. Content type: Research

    Metallothionein (MT) is a small, cysteine-rich, metal-binding protein that plays an important role in protecting against toxicity of heavy metal and chemicals. This study was aimed to define diurnal and sex va...

    Authors: Dan Zhang, Tao Jin, Yi-qiao Xu, Yuan-Fu Lu, Qin Wu, Yu-Kun Jennifer Zhang and Jie Liu

    Citation: Journal of Circadian Rhythms 2012 10:5

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  12. Content type: Research

    Recent studies on humans and rodents have suggested that the timing of food intake plays an important role in circadian regulation and metabolic health. Consumption of high-fat foods during the inactive period...

    Authors: Yuta Fuse, Akiko Hirao, Hiroaki Kuroda, Makiko Otsuka, Yu Tahara and Shigenobu Shibata

    Citation: Journal of Circadian Rhythms 2012 10:4

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  13. Content type: Research

    Valproic acid (VPA) is an antiepileptic drug widely used for the treatment of absence seizures and generalized tonic-clonic seizures. The present work aims to study whether VPA-induced toxicity varies accordin...

    Authors: Wafa Ben-Cherif, Ichrak Dridi, Karim Aouam, Mossadok Ben-Attia, Alain Reinberg and Naceur A Boughattas

    Citation: Journal of Circadian Rhythms 2012 10:3

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  14. Content type: Research

    Physical activity as measured by activity counts over short time intervals across a 24 h period are often used to assess circadian variation. We are interested in characterizing circadian patterns in activity ...

    Authors: Semhar Ogbagaber, Paul S Albert, Daniel Lewin and Ronald J Iannotti

    Citation: Journal of Circadian Rhythms 2012 10:2

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  15. Content type: Research

    Menopause-associated thermoregulatory dysfunction can lead to symptoms such as hot flushes severely impairing quality of life of affected women. Treatment effects are often assessed by the ovariectomized rat m...

    Authors: Dorothee Girbig, Karsten Keller, Katja Prelle, Vladimir Patchev, Richardus Vonk and Bernd-Wolfgang Igl

    Citation: Journal of Circadian Rhythms 2012 10:1

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  16. Content type: Research

    The Magel2 gene is most highly expressed in the suprachiasmatic nucleus of the hypothalamus, where its expression cycles in a circadian pattern comparable to that of clock-controlled genes. Mice lacking the Magel...

    Authors: Julia Devos, Sara V Weselake and Rachel Wevrick

    Citation: Journal of Circadian Rhythms 2011 9:12

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  17. Content type: Research

    Actigraphy provides a way to objectively measure activity in human subjects. This paper describes a novel family of statistical methods that can be used to analyze this data in a more comprehensive way.

    Authors: Jia Wang, Hong Xian, Amy Licis, Elena Deych, Jimin Ding, Jennifer McLeland, Cristina Toedebusch, Tao Li, Stephen Duntley and William Shannon

    Citation: Journal of Circadian Rhythms 2011 9:11

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  18. Content type: Research

    Many previous studies have documented seasonal variation in suicides globally. We re-assessed the seasonal variation of suicides in Finland and tried to relate it to the seasonal variation in daylength and amb...

    Authors: Laura Hiltunen, Kirsi Suominen, Jouko Lönnqvist and Timo Partonen

    Citation: Journal of Circadian Rhythms 2011 9:10

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  19. Content type: Research

    In university health care settings, students with psychosomatic complaints often have chronotypic problems. For this reason, we investigated a potential connection between psychosomatic complaints and circadia...

    Authors: Mitsuo Nagane, Rie Suge and Shu-Ichi Watanabe

    Citation: Journal of Circadian Rhythms 2011 9:9

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  20. Content type: Research

    It has been reported that rs4446909, a single nucleotide polymorphism (SNP) in the promoter of acetylserotonin methyltransferase (ASMT), influences the expression of the ASMT enzyme. The common G allele is associ...

    Authors: Daniel F Kripke, Caroline M Nievergelt, Greg J Tranah, Sarah S Murray, Michael J McCarthy, Katharine M Rex, Neeta Parimi and John R Kelsoe

    Citation: Journal of Circadian Rhythms 2011 9:8

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  21. Content type: Research

    Adenosine 5-triphosphate (ATP) and its breakdown products ADP and adenosine can act as extracellular messengers in a range of biological processes. Extracellular adenine nucleotides are metabolized by a number...

    Authors: Andressa Souza, Bernardo C Detanico, Liciane F Medeiros, Joanna R Rozisky, Wolnei Caumo, Maria Paz L Hidalgo, Ana Maria O Battastini and Iraci LS Torres

    Citation: Journal of Circadian Rhythms 2011 9:7

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  22. Content type: Research

    The role played by calcium as a regulator of circadian rhythms is not well understood. The effect of the pharmacological inhibition of the ryanodine receptor (RyR), inositol 1,4,5-trisphosphate receptor (IP3R), a...

    Authors: Adrián Báez-Ruiz and Mauricio Díaz-Muñoz

    Citation: Journal of Circadian Rhythms 2011 9:6

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  23. Content type: Research

    Sodium nitroprusside (SNP) is widely used in pharmacological studies as a potent vasodilator or a nitric oxide donor. SNP-induced ataxic effects were assessed in mice by the Joulou-Couvoisier test. Swiss albin...

    Authors: Mamane Sani, Hichem Sebai, Naceur A Boughattas and Mossadok Ben-Attia

    Citation: Journal of Circadian Rhythms 2011 9:5

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  24. Content type: Research

    Many cancer patients report poor sleep quality, despite having adequate time and opportunity for sleep. Satisfying sleep is dependent on a healthy circadian time structure and the circadian patterns among canc...

    Authors: James F Grutsch, Patricia A Wood, Jovelyn Du-Quiton, Justin L Reynolds, Christopher G Lis, Robert D Levin, Mary Ann Daehler, Digant Gupta, Dinah Faith T Quiton and William JM Hrushesky

    Citation: Journal of Circadian Rhythms 2011 9:4

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  25. Content type: Research

    Although most freshwater planarias are well known photonegative organisms, their diel rhythms have never been quantified. Differences in daily activity rhythms may be particularly important for temperate-clima...

    Authors: Paola Lombardo, Marco Giustini, Francesco Paolo Miccoli and Bruno Cicolani

    Citation: Journal of Circadian Rhythms 2011 9:2

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  26. Content type: Short paper

    Although various acceptable and easy-to-use devices have been used for saliva collection, cotton swabs are among the most common ones. Previous studies reported that cotton swabs yield a lower level of melaton...

    Authors: Tomoaki Kozaki, Soomin Lee, Takayuki Nishimura, Tetsuo Katsuura and Akira Yasukouchi

    Citation: Journal of Circadian Rhythms 2011 9:1

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  27. Content type: Research

    Animals, including humans, exhibit a variety of biological rhythms. This article describes a method for the detection and simultaneous comparison of multiple nycthemeral rhythms.

    Authors: Armin M Stroebel, Matthias Bergner, Udo Reulbach, Teresa Biermann, Teja W Groemer, Ingo Klein and Johannes Kornhuber

    Citation: Journal of Circadian Rhythms 2010 8:10

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  28. Content type: Debate

    Examples of circadian rhythms have been described in eukaryotic organisms and in photosynthetic bacteria, but direct proof of their existence in other prokaryotes is limited and has been largely ignored. The a...

    Authors: María I Soriano, Begoña Roibás, Ana B García and Manuel Espinosa-Urgel

    Citation: Journal of Circadian Rhythms 2010 8:8

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  29. Content type: Research

    Studies have shown that insomnia is a common sleep disorder among patients with end-stage renal disease (ESRD). This study aimed to assess the prevalence of insomnia in Saudi patients with ESRD who are on main...

    Authors: Hamdan H Al-Jahdali, Haithm A Khogeer, Waleed A Al-Qadhi, Salim Baharoon, Hani Tamim, Fayez F Al-Hejaili, Saeed M Al-Ghamdi and Abdullah A Al-Sayyari

    Citation: Journal of Circadian Rhythms 2010 8:7

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  30. Content type: Research

    Immunosenescence is a process that affects all cell compartments of the immune system and the contribution of the immune system to healthy aging and longevity is still an open question. Lymphocyte subpopulatio...

    Authors: Gianluigi Mazzoccoli, Angelo De Cata, Antonio Greco, Marcello Damato, Nunzia Marzulli, Mariangela Pia Dagostino, Stefano Carughi, Federico Perfetto and Roberto Tarquini

    Citation: Journal of Circadian Rhythms 2010 8:6

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  31. Content type: Research

    Most mammals are seasonal breeders whose gonads grow to anticipate reproduction in the spring and summer. As day length increases, secretion increases for two gonadotropins, luteinizing hormone (LH) and follic...

    Authors: Daniel F Kripke, Jeffrey A Elliott, Shawn D Youngstedt, Barbara L Parry, Richard L Hauger and Katharine M Rex

    Citation: Journal of Circadian Rhythms 2010 8:5

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  32. Content type: Research

    Recent evidence suggests a two-way interaction between the immune and circadian systems. Circadian control of immune factors, as well as the effect of immunological variables on circadian rhythms, might be key...

    Authors: Leandro P Casiraghi, Diego O Croci, Francoise Poirier, Gabriel A Rabinovich and Diego A Golombek

    Citation: Journal of Circadian Rhythms 2010 8:4

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  33. Content type: Review

    Circadian rhythms are daily oscillations of multiple biological processes directed by endogenous clocks. The circadian timing system comprises peripheral oscillators located in most tissues of the body and a c...

    Authors: Sobia Rana and Saqib Mahmood

    Citation: Journal of Circadian Rhythms 2010 8:3

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  34. Content type: Review

    The present paper reflects a work in progress toward a definition of circadian light, one that should be informed by the thoughtful, century-old evolution of our present definition of light as a stimulus for t...

    Authors: Mark S Rea, Mariana G Figueiro, Andrew Bierman and John D Bullough

    Citation: Journal of Circadian Rhythms 2010 8:2

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  35. Content type: Research

    Depression and alcohol abuse or dependence (AUD) co-occur in the general population more frequently than expected by chance. Alcohol use influences the circadian rhythms generated by the central pacemaker in t...

    Authors: Louise K Sjöholm, Leena Kovanen, Sirkku T Saarikoski, Martin Schalling, Catharina Lavebratt and Timo Partonen

    Citation: Journal of Circadian Rhythms 2010 8:1

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  36. Content type: Research

    In the eye, melatonin plays a role in promoting light sensitivity at night and modulating many aspects of circadian retinal physiology. It is also an inhibitor of retinal dopamine, which is a promoter of day v...

    Authors: Anne-Marie Gagné, Konstantin V Danilenko, Serge G Rosolen and Marc Hébert

    Citation: Journal of Circadian Rhythms 2009 7:14

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  37. Content type: Research

    Restless Legs Syndrome (RLS) is a common neurological movement disorder characterized by symptoms that follow a circadian pattern. Night and rotating shift work schedules exert adverse effects on functions of ...

    Authors: Akbar Sharifian, Marjan Firoozeh, Gholamreza Pouryaghoub, Mehran Shahryari, Mohsen Rahimi, Mohammad Hesamian and Ali Fardi

    Citation: Journal of Circadian Rhythms 2009 7:12

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  38. Content type: Review

    Evidence that circadian food-anticipatory activity and temperature rhythms are absent in Bmal1 knockout mice and rescued by restoration of Bmal1 expression selectively in the dorsomedial hypothalamus was publishe...

    Authors: Ralph E Mistlberger, Ruud M Buijs, Etienne Challet, Carolina Escobar, Glenn J Landry, Andries Kalsbeek, Paul Pevet and Shigenobu Shibata

    Citation: Journal of Circadian Rhythms 2009 7:11

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  39. Content type: Research

    Students suffering from psychosomatic symptoms, including drowsiness and feelings of melancholy, often have basic lifestyle problems. The aim of this study was to investigate whether psychosomatic complaints m...

    Authors: Mitsuo Nagane, Kazunori Yoshimura, Shu-Ichi Watanabe and Masahiko Nomura

    Citation: Journal of Circadian Rhythms 2009 7:10

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  40. Content type: Review

    A number of recent studies have debated the existence and nature of clocks outside the suprachiasmatic nucleus that may underlie circadian rhythms in conditions of food entrainment or methamphetamine administr...

    Authors: Patrick M Fuller, Jun Lu and Clifford B Saper

    Citation: Journal of Circadian Rhythms 2009 7:9

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  41. Content type: Research

    Light exposure in the late evening and nighttime and a delay of the sleep/dark episode can phase delay the circadian clock. This study assessed the size of the phase delay produced by a single light pulse comb...

    Authors: Jillian L Canton, Mark R Smith, Ho-Sun Choi and Charmane I Eastman

    Citation: Journal of Circadian Rhythms 2009 7:8

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  42. Content type: Research

    Numerous processes in the living body exhibit daily rhythmicity. In this study, we characterized a daily rhythm of blood fluidity and identified its determinants.

    Authors: Tatsushi Kimura, Tsutomu Inamizu, Kiyokazu Sekikawa, Masayuki Kakehashi and Kiyoshi Onari

    Citation: Journal of Circadian Rhythms 2009 7:7

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