1.Optogenetic and Chemogenetic Approaches for Studying Astrocytes and Gliotransmitters.
Juwon BANG ; Hak Yeong KIM ; Hyosang LEE
Experimental Neurobiology 2016;25(5):205-221
The brain consists of heterogeneous populations of neuronal and non-neuronal cells. The revelation of their connections and interactions is fundamental to understanding normal brain functions as well as abnormal changes in pathological conditions. Optogenetics and chemogenetics have been developed to allow functional manipulations both in vitro and in vivo to examine causal relationships between cellular changes and functional outcomes. These techniques are based on genetically encoded effector molecules that respond exclusively to exogenous stimuli, such as a certain wavelength of light or a synthetic ligand. Activation of effector molecules provokes diverse intracellular changes, such as an influx or efflux of ions, depolarization or hyperpolarization of membranes, and activation of intracellular signaling cascades. Optogenetics and chemogenetics have been applied mainly to the study of neuronal circuits, but their use in studying non-neuronal cells has been gradually increasing. Here we introduce recent studies that have employed optogenetics and chemogenetics to reveal the function of astrocytes and gliotransmitters.
Astrocytes*
;
Brain
;
In Vitro Techniques
;
Ions
;
Membranes
;
Neurons
;
Optogenetics*
2.Equol Production and Increased Leukocyte Mitochondrial DNA in Postmenopausal Women.
Juwon AHN ; Seungha BAEK ; Kijeong KIM ; Hyowon BANG ; Jaehong KO ; Jung Ha KIM
Korean Journal of Health Promotion 2015;15(3):108-114
BACKGROUND: Equol, a metabolite of diadzein, is produced by some intestinal bacteria. Equol acts as an estrogen receptor agonist and has been reported to have several beneficial health effects. Leukocytes play an important role in the pathogenesis of autoimmune, metabolic, and cardiovascular diseases. Decreased leukocyte mitochondrial DNA (mtDNA) content, as an index of mitochondrial function, is associated with metabolic syndrome, bone mineral density, and aging. The possible association between equol production and leukocyte mitochondrial function has not been studied to date. Therefore, we investigated whether equol production is associated with leukocyte mtDNA copy number in postmenopausal women. METHODS: This observational cross-sectional study included 71 postmenopausal women. They completed a lifestyle questionnaire and medical history. In addition, a dietary assessment using a 24-hour recall method and food frequency questionnaire, anthropometric evaluation, and blood sampling were conducted. Serum equol concentration was measured in the fasting state. Leukocyte mtDNA copy number was measured by real-time polymerase chain reaction. RESULTS: Among older females, 33.8% were equol producers. The leukocyte mtDNA copy number was lower in non-equol producers versus equol producers. Furthermore, the leukocyte mtDNA copy number was positively associated with the serum equol concentration (r=0.42, P<0.01). Stepwise multiple regression analysis showed that equol production (beta=47.864, P<0.01) was an independent factor associated with mtDNA copy number. CONCLUSIONS: Equol production was associated with elevated mtDNA content in the peripheral blood of postmenopausal women. This finding suggests that the beneficial health effects of equol in postmenopausal women may be related to increased mitochondrial function.
Aging
;
Bacteria
;
Bone Density
;
Cardiovascular Diseases
;
Cross-Sectional Studies
;
DNA
;
DNA, Mitochondrial*
;
Equol*
;
Estrogens
;
Fasting
;
Female
;
Humans
;
Leukocytes*
;
Life Style
;
Mitochondria
;
Postmenopause
;
Real-Time Polymerase Chain Reaction
3.Effects of transient threshold shift and ambient noise on sensitivity and specificity of first screening of special health examination for noise.
Jong Uk WON ; Moon Kyoo BANG ; Joong Ho SONG ; Sedn Ah JEONG ; Jae Suk SONG ; Jaehoon ROH
Korean Journal of Occupational and Environmental Medicine 2000;12(2):269-276
OBJECT: This study was performed to increase the sensitivity and specificity for screening the examinee of second hearing test. METHODS: Study subjects were 219 workers who exposed more than average 80dB. They were taken the hearing test two times, before noise exposure and at 1 hour to 4 hours after worksite noise exposure. To investigate the ambient noise workers who were taken the hearing test in the test room which ambient noise was less than 45dB were classified Group I and the others were classified Group E. To calculate the sensitivity and specificity we made it gold standard whether worker had noise induced hearing loss. RESULTS: Difference of hearing loss between before and after noise exposure for left and right ear was 11. 4 dB and 11. 7 dB respectively at 500 Hz, 8. 7 dB and 9. 6 dB at 1, 000 Hz, 6. 3 dB and 6. 9 dB at 2, 000 Hz and 6. 9 dB and 7. 4 dB at 4, 000 Hz in Group I. That for left ear and right ear was 5.8 dB and 4.9 dB at 500 Hz respectively, 5.4 dB and 6.4 dB at 1,000 Hz, 6.3 dB and 5.3 dB at 2,000 Hz, and 5.5 dB and 5.8 dB at 4,000 Hz in Group E. The sensitivity was 100 in both Groups and the specificity was increased to 58. 3 and 71. 8 in Group I and Group 3 respectively until 10 dB was deducted from hearing level at 1, 000 Hz and 4, 000 Hz. CONCLUSION: When the screening hearing test was performed at worksite, we might deduct 10 dB from measured hearing level to increase the specificity without reduction of sensitivity.
Ear
;
Hearing
;
Hearing Loss
;
Hearing Tests
;
Mass Screening*
;
Noise*
;
Sensitivity and Specificity*
;
Workplace