• Title/Summary/Keyword: Rhythmicity

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The Expression of a Cytosolic Fructose-1,6-Bisphosphatase, a Key Enzyme in Sucrose Biosynthesis, Gene was Diurnally Fluctuated and Increased in Cold Acclimated Leaves of Chinese Cabbage

  • Leen, Jeong-Yeo;Song, Ha-Young;Lim, Yong-Pyo;Hur, Yoon-Kang
    • Journal of Plant Biotechnology
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    • v.33 no.2
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    • pp.123-131
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    • 2006
  • Chinese cabbage (Brassica rapa ssp. pekinesis) is one of the most important vegetable crops in korea and other East Asian countries. Cytosolic fructose-1,6-bisphospha-tase (cytFBPase) is a key enzyme in sucrose biosyn-thesis, which controls the sucrose levels as well as the productivity at plants. The Chinese cabbage cytFBPase gene, BrFBPase, encodes the 340 amino acid polypep-tide, giving a theoretical molecular weight of 37.2 kD and a isolectric point of 5.4. BrFBPase showed high sequence identity with Brassica homologs and its functional domains, such as 12,6P$_2$ binding site or active site and F6P binding site, were highly conserved in diverse sources of organisms. Although the genome of Chinese cabbage seemed to be triplicated, BrFBPase appears to be a single copy gene. The expression of BrFBPase was examined at transcript and protein levels under various conditions. BrFBPase expression was observed only in photosynthetic source tissue, not in sink tissue. The expression was slightly higher during the day than at night, and it showed a diurnal cycle with circadian rhythmicity. Short-term exposure to low temperature inhibited the expression of the BrFBPase, while long-term exposure increased the expression, supporting that sugar levels are high in late autumn when temperature are low.

Motility and Absorptive Capacity of the Ileum in Acute Hemorrhage (급성실혈시의 회장운동과 흡수기능)

  • Hwang, Jeong-Woon
    • The Korean Journal of Physiology
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    • v.7 no.2
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    • pp.39-47
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    • 1973
  • The influences of the acute hemorrhage on the intestinal functions were studied in the rabbits subjected to acute bleeding, amounting 1.5-2% of the body weight. The motility and the absorptive capacity of the ileum were compared before and after the bleeding. Transfusion of shed blood was also performed in order to see whether the deteriorations were reversible or not. The tension developed in the direction of the longitudinal axis of the ileum was recorded through an appropriate transducer, and the frequency of the rhythmic contraction was counted throughout the procedure. Test solution, 10ml in amount, was placed in the loop of the ileum, and the samples were drawn at zero time and at 20 minutes. Triplicated procedures were repeated on the same loop;namely, before and after bleeding and after transfusion. The test solution was composed of 200 mg% urea, 218 mEq/l of NaCl and 150 mg% of polyethylene glycol (PEG) No. 4,000 in distilled water. The latter substance was used as a marker substance for the volume change of the loop. The results obtained were as follows; 1. The motility of the ileum suffered little effects by acute hemorrhage. However, minor fluctuations were seen in the frequency of the rhythm, showing a slight tendency of decreasing rhythmicity, and it was reversed by transfusion. 2. Diminution of absorptive capacity of urea was noticed in acute hemorrhage and it was interpreted as the consequence of the secondary effect of the retardation of the active transport mechanism governing the sodium transport 3. Absorption rate of the sodium ion was dropped in the hemorrhage, suggesting the indispensable need of the blood supply. 4. Osmolarity of the luminal fluid remained higher in the case of acute hemorrhage. 5. There was a tendency of retaining more fluid in the intestinal lumen in acute hemorrhage, comparing with that observed prior to the bleeding. 6. The deteriorations in the absorptive capacity were restored by transfusion of shed blood.

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Roles of $Ca^{2+}-Activated\;K^+$ Conductances on Spontaneous Firing Patterns of Isolated Rat Medial Vestibular Nucleus Neurons

  • Chun, Sang-Woo;Jun, Jae-Woo;Park, Byung-Rim
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.1
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    • pp.1-8
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    • 2000
  • To investigate the contributions of intrinsic membrane properties to the spontaneous activity of medial vestibular nucleus (MVN) neurons, we assessed the effects of blocking large and small calcium-activated potassium channels by means of patch clamp recordings. Almost all the MVN neurons recorded in neonatal $(P13{\sim}P17)$ rat were shown to have either a single deep after-hyperpolarization (AHP; type A cells), or an early fast and a delayed slow AHP (type B cells). Among the recorded MVN cells, immature action potential shapes were found. Immature type A cell showed single uniform AHP and immature B cell showed a lack of the early fast AHP, and the delayed AHP was separated from the repolarization phase of the spike by a period of isopotentiality. Application of apamin and charybdotoxin (CTX), which selectively block the small and large calcium-activated potassium channels, respectively, resulted in significant changes in spontaneous firings. In both type A and type B cells, CTX (20 nM) resulted in a significant increase in spike frequency but did not induce bursting activity. By contrast, apamin (300 nM) selectively abolished the delayed slow AHP and induced bursting activity in type B cells. Apamin had no effect on the spike frequency of type A cells. These data suggest that there are differential roles of apamin and CTX sensitive potassium conductances in spontaneous firing patterns of MVN neurons, and these conductances are important in regulating the intrinsic rhythmicity and excitability.

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Expression types and aesthetic characteristics of modern fashion applying the formativeness of symmography (시모그래피의 조형성을 응용한 현대 패션 디자인의 표현유형과 미적 특성 연구)

  • Kwon, Giyoung
    • The Research Journal of the Costume Culture
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    • v.29 no.3
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    • pp.361-373
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    • 2021
  • The purpose of this study is to contribute to the role of lines in creative design development by analyzing the expression types and aesthetic characteristics of modern fashion using geometric formativeness of symmography. A literature study was conducted of works since 2009 to examine the general consideration of lines together with analysis of the concept and characteristics of symmography in the formative arts field, and to analyze the expression types and aesthetic characteristics of modern fashion design using the formativeness of symmography. The infinite sense of formativeness and original expression of symmography are used in formative arts such as space design, installation art, and industrial design. Expression types of modern fashion design using geometric formativeness of symmography can be classified into the following three types: two-dimensional graphic pattern, relief surface, and three-dimensional spatial. First, the two-dimensional graphic pattern type forms an optical pattern, providing individuality and visual interest to the textile design. Second, the relief surface type expresses the plane in various ways, so that the thickness changes according to how lines overlap. Third, the three-dimensional spatial type expands the boundaries of clothing and creates a fantastic spatial beauty. Next, the aesthetic formativeness of fashion design using symmography can be classified into repetitive rhythmicity, geometric self-similarity, and optical spatiality. Symmography enables a myriad of geometric patterns to be developed depending on material, color, and the designer's imagination, and helps inspire a variety of designs in fashion that sculpt a three-dimensional human body.

[$PGE_2$ Regulates Pacemaker Currents through $EP_2-Receptor$ in Cultured Interstitial Cells of Cajal from Murine Small Intestine

  • Choi, Seok;Cho, Kyung-Won;Reu, Jong-Hyun;Kim, Jun-Soo;Mun, Hyun-Sik;Kim, Myung-Young;Park, Kwang-Chul;Heo, Gwang-Sik;Chang, Sung-Jong;Yeum, Cheol-Ho;Yoon, Pyung-Jin;Jun, Jae-Yeoul
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.3
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    • pp.153-159
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    • 2004
  • The interstitial cells of Cajal (ICCs) are the pacemaker cells in gastrointestinal tract and generate electrical rhythmicity in gastrointestinal muscles. Therefore, ICC may be modulated by endogenous agents such as neurotransmitter, hormones, and prostaglandins (PGs). In the present study, we investigated the effects of prostaglandins, especially $PGE_2$, on pacemaker currents in cultured ICCs from murine small intestine by using whole-cell patch clamp techniques. ICCs generated spontaneous slow waves under voltage-clamp conditions and showed a mean amplitude of $-452{\pm}39\;pA$ and frequency of $18{\pm}2$ cycles/min (n=6). Treatments of the cells with $PGE_2$ $(1\;{\mu}M)$ decreased both the frequency and amplitude of the pacemaker currents and increased the resting currents in the outward direction. $PGE_2$ had only inhibitory effects on pacemaker currents and this inhibitory effect was dose-dependent. For characterization of specific membrane EP receptor subtypes, involved in the effects of $PGE_2$ on pacemaker currents in ICCs, EP receptor agonists were used: Butaprost $(1\;{\mu}M)$, $EP_2$ receptor agonist, reduced the spontaneous inward current frequency and amplitude in cultured ICCs (n=5). However sulprostone $(1\;{\mu}M)$, a mixed $EP_1$ and $EP_3$ agonist, had no effects on the frequency, amplitude and resting currents of pacemaker currents (n=5). SQ-22536 (an inhibitor of adenylate cyclase; $100\;{\mu}M$) and ODQ (an inhibitor of guanylate cyclase; $100\;{\mu}M$) had no effects on $PGE_2$ actions of pacemaker currents. These observations indicate that $PGE_2$ alter directly the pacemaker currents in ICCs, and that the $PGE_2$ receptor subtypes involved are the $EP_2$ receptor, independent of cyclic AMP- and GMP-dependent pathway.

TEMPERAMENTAL CHARACTERISTICS OF ATTENTION DEFICIT HYPERACTIVITY DISORDER (주의력결핍 ${\cdot}$ 과잉운동장애아의 기질적 특성)

  • Cho, Soo-Churl;Kim, Dong-Hyun;Kim, Ja-Sung
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.4 no.1
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    • pp.114-123
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    • 1993
  • The authors applied Toddler Temperament Scale(TTS) to ADHD patient group, other disease group and normal control group to elucidate temperamental characteristics of ADHD patients in their toddler stage. 1) ADHD group showed significant difference from the control group in 'activity', 'rhythmicity', 'approach', 'adaptability', 'intensity', 'persistence' and 'threshold' categories. 2) ADHD group and other disease showed significant difference from the control group in 'adaptability' and 'persistence' categories. 3) ADHD group was significantly different from other disease group or control group in 'activity' and 'approach' categories. 4) In total scores of TTS, ADHD group and other diease group showed significant difference from control group. 5) Classification ratio of TTS for ADHD by discriminant analysis was 84.3%. Above results suggest that the ADHD patients may reveal characteristic traits in their toddler stage Further research should be focused on the development and refinement of assessment tools for the early detection and prevention for ADHD.

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Changes in Serum Cortisol Concentration Due to Boarding Stress in Dogs (위탁견에서 스트레스에 의한 혈중 Cortisol의 농도 변화)

  • Lee, Sang-Kil;Song, In-Soo;Park, Soo-Kyoung;Hong, Yong-Geun;Kang, Chung-Boo
    • Journal of Veterinary Clinics
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    • v.27 no.1
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    • pp.35-41
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    • 2010
  • Among the dogs boarding at an animal hospital, 10 dogs each were selected as a free boarding group and a kennel boarding group. Each group was further divided into 5 puppies and 5 mature dogs to examine the changes in their serum cortisol concentrations during boarding (5 days). We collected blood at day 8 and then analyzed the blood corpuscles, ran a biochemical serum test, and an additional urine test before boarding to check their health status. After collecting the dog's blood at 9:00 am, 3:00 pm, and 9:00 pm, we analyzed the cortisol concentration by the radioimmunoassay (RIA) method. The daily serum cortisol concentration at 9:00 am, 3:00 pm, and 9:00 pm, had a circadian rhythm during both the free and kennel boarding periods in both puppies and adults. Furthermore, the average daily serum cortisol concentration was significantly increased during the 1st, 2nd, and 3rd day after free boarding in the puppy group (P < 0.01). In adults from the free boarding group, the serum cortisol concentration dramatically increased on the 1st day (P < 0.01), as well as on the 2nd and 3rd day (P < 0.05). Interestingly, the average daily serum cortisol concentration was significantly increased on the 1st day after kennel boarding as well as during the entire period of kennel boarding in the puppy group (P < 0.05). In the adult kennel boarding group, serum cortisol concentration was significantly increased during the whole kennel boarding period (P < 0.01). An interesting result was that circadian rhythmicity in the sum of the daily serum cortisol concentrations was present in the free boarding group, but not in the kennel boarding group in both puppies and adults. In summary, cortisol was released depending on the degree of stress in free and kennel boarded dogs. Taken together, these results suggest that cortisol, a stress hormone, should be maintained at physiological concentrations in a circadian rhythm when the animals are hospitalized.

Effects of Temperature and Photoperiod on Male Activity in Laspeyresia pomonella (L.) in New York (온도와 광주기 조건이 코드링나방 수컷의 활동력에 마치는 영향)

  • SONG, YOO HAN;Ridel, Helmut
    • Korean journal of applied entomology
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    • v.24 no.2 s.63
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    • pp.71-77
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    • 1985
  • The male activity in Laspeyresia pomonella (L.) measured by an activity recording device in New York had two distinct peaks, the first peak at lights-off and the second one at ligts-on signal, under the defined conditions of temperature above $23^{\circ}C$ and light:dark (LD) 16:8 regime. The activity initiation of the first activity was observed four to six hours prior to the onset of scotophase and seened to be entraind by lights-off cue. Under the continuous photophase (LL) the activity period freeran with a period slightly greater than 24 hours, indicating that the rhythmicity is circadian The activity pattern was measured in eight different temperature conditions ranging from $11.3^{\circ}\;to\;30^{\circ}C$ under LD 16:8 regime. No activity was observed at $11.3^{\circ}C$ which seems to be temperature threshold for activity. The second peak of activity at lights-on signal disappeared at the temperature below $20^{\circ}C$ and the activity in scotophase was also suppressed at the temperature lower than $18^{\circ}C$. At the temperature range from $20^{\circ}\;to\;30^{\circ}C$, as temperature increased the second peak in the morning became larger and the activty in the scotophase was also increased. Because of the activity increase in the scotophase with rising temperature, the mean time of activity shifted towards the scotophase. The shift of the moth male activity period with the change of ambient temperature appears to be due to the suppression of activity under cool temperature (below $20^{\circ}C$) in scotophase.

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Effects of Systemic and Focal Hypoxia on the Activities of Rostral Ventrolateral Medullary Neurons in Cats

  • Yan, Hai-Dun;Kim, Charn;Kim, Ji-Mok;Lim, Won-Il;Kim, Sang-Jeong;Kim, Jun
    • The Korean Journal of Physiology
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    • v.30 no.1
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    • pp.105-116
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    • 1996
  • Rendering the brain ischemic would evoke the cerebral ischemic reflex which is characterized by an arterial pressor response, apnea and bradycardia. Since the rostral ventrolateral medulla (RVLM) is known to play a key role in the maintenance of normal cardiopulmonary activity, during the cerebral ischemic reflex some cardiac related cells should be excited and respiration related cells inhibited. In this context, the responses of RVLM neurons to systemie and focal hypoxia were analyzed in the present study. Twenty-five adult cats of either sex were anesthetized with ${\alpha}-chloralose$ and the single neuronal activities were identified from RVLM area. For the induction of focal hypoxia in the recording site, sodium cyanide was applied iontophoretically and for systemic hypoxia the animal was ventilated with nitrogen gas for a twenty-second period. Cellular activities were analyzed in terms of their discharge pattern and responses to the hypoxia by using post-stimulus time and single-pass time histograms. Of eighteen cardiac related cells recorded from the RVLM area, twelve cells were excited by iontophoresed sodium cyanide and of twenty-five respiration related cells, fourteen cells were excited by iontophoresed sodium cyanide. Remaining cells were either inhibited or unaffected. Eight of fifteen cells tested with iontophoresed sodium lactate were excited and remaining seven cells were inhibited. Systemic hypoxia induced by nitrogen gas inhalation elevated the arterial blood pressure, but excited, inhibited or unaffected the single neuronal activities. Some cells showed initial excitation followed by inhibition during the systemic hypoxia. Bilateral vagotomy resulted in a decrease of arterial pressor response to the systemic hypoxia, and a slight decrease in the rhythmicity related to cardiac and/or respiratory rhythms. The single neuronal responses to either systemic or focal hypoxia were not affected qualitatively by vagotomy. From the above results, it was concluded that the majority of the cardiac- and respiration- related neurons in the rostral ventrolateral medulla be excited by hypoxia, not through the mediation of peripheral chemoreceptors, and along with the remaining inhibited cells, all these cells be involved in the mediation of cerebral ischemic reflex.

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Neuronal Mechanisms that Regulate Vitellogenesis in the Fruit Fly (노랑초파리 난황형성과정 제어 신경 메커니즘)

  • Kim, Young-Joon;Zhang, Chen
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.109-115
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    • 2022
  • Vitellogenesis is the process by which yolk accumulates in developing oocytes. The initiation of vitellogenesis represents an important control point in oogenesis. When females of the model insect Drosophila melanogaster molt to become adults, their ovaries lack mature vitellogenic oocytes, only producing them after reproductive maturation. After maturation, vitellogenesis stops until a mating signal re-activates it. Juvenile hormone (JH) from the endocrine organ known as the corpora allata (CA) is the major insect gonadotropin that stimulates vitellogenesis, and the seminal protein sex peptide (SP) has long been implicated as a mating signal that stimulates JH biosynthesis. In this review, we discuss our new findings that explain how the nervous system gates JH biosynthesis and vitellogenesis associated with reproductive maturation and the SP-induced post-mating response. Mated females exhibit diurnal rhythmicity in oogenesis. A subset of brain circadian pacemaker neurons produce Allatostatin C (AstC) to generate a circadian oogenesis rhythm by indirectly regulating JH and vitellogenesis through the brain insulin-producing cells. We also discuss genetic evidence that supports this model and future research directions.