1.Time Perception and Memory in Mild Cognitive Impairment and Alzheimer’s Disease: A Preliminary Study
Sung-Ho WOO ; Jarang HAHM ; Jeong-Sug KYONG ; Hang-Rai KIM ; Kwang Ki KIM
Dementia and Neurocognitive Disorders 2023;22(4):148-157
Background:
and Purpose: Episodic memory is a system that receives and stores information about temporally dated episodes and their interrelations. Our study aimed to investigate the relevance of episodic memory to time perception, with a specific focus on simultaneity/ order judgment.
Methods:
Experiment 1 employed the simultaneity judgment task to discern differences in time perception between patients with mild cognitive impairment or dementia, and agematched normals. A mathematical analysis capable of estimating subjects’ time processing was utilized to identify the sensory and decisional components of temporal order and simultaneity judgment. Experiment 2 examined how differences in temporal perception relate to performance in temporal order memory, in which time delays play a critical role.
Results:
The temporal decision windows for both temporal order and simultaneity judgments exhibited marginal differences between patients with episodic memory impairment, and their healthy counterparts (p = 0.15, t(22) = 1.34). These temporal decision windows may be linked to the temporal separation of events in episodic memory (Pearson’s ρ = −0.53, p = 0.05).
Conclusions
Based on our findings, the frequency of visual events accumulated and encoded in the working memory system in the patients’ and normal group appears to be approximately (5.7 and 11.2) Hz, respectively. According to the internal clock model, a lower frequency of event pulses tends to result in underestimation of event duration, which phenomenon might be linked to the observed time distortions in patients with dementia.
2.The Bone Response to Hormone Replacement Therapy according to Basal Bone Mineral Density in Postmenopausal Women.
Jung Gu KIM ; Kwang Rai KIM ; Byung Chul GEE ; Seok Hyun KIM ; Young Min CHOI ; Shin Yong MOON ; Jin Yong LEE
Korean Journal of Obstetrics and Gynecology 2001;44(8):1450-1454
OBJECTIVE: To investigate the incidence of non-responder to hormone replacement therapy (HRT) and to evaluate the bone response to HRT according to basal bone mineral density(BMD) in postmenopausal women. METHODS: A total of 211 postmenopausal women received either continuous combined estrogen-progestogen replacement (n=112) or estrogen replacement (n=99) for 1 years. BMD at the lumbar spine and femoral neck was measured by dual energy X-ray absorptiometry (DEXA) before and 1 year after HRT. RESULTS: The incidence of non-responder (women with > 3% bone loss per year) to HRT was 9.2% in the lumbar spine, and 23.8% in femoral neck. Estrogen replacement group had a higher incidence of non-responder than combined replacement group. Non-responder group had a higher basal BMD at the lumbar spine than responder group, and showed bone loss rate of 7.6% per year. After 1 year of HRT, postmenopausal women with osteoporosis showed a higher rate of increase in BMD at the lumbar sine and femoral neck than women with normal BMD or osteopenia. CONCLUSION: The non-responders to HRT have a higher basal lumbar BMD, compared with responders. The higher basal BMD at the lumbar spine is, the less bone conservation effect of HRT is.
Absorptiometry, Photon
;
Bone Density*
;
Bone Diseases, Metabolic
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Estrogen Replacement Therapy
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Female
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Femur Neck
;
Hormone Replacement Therapy*
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Humans
;
Incidence
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Osteoporosis
;
Spine
3.Pituitary oncocytoma.
Eun Jig LEE ; Kyung Rai KIM ; Hyun Chul LEE ; Kwang Jin AHN ; Yoon Sok CHUNG ; Sung Kil LIM ; Kap Bum HUH ; Woo Ick YANG ; Woo Hee CHUNG ; Tae Seung KIM ; Do Heum YOON ; Sang Seop CHUNG
Journal of Korean Society of Endocrinology 1992;7(1):16-23
No abstract available.
Adenoma, Oxyphilic*
4.Effect of Leaf-Extract from Camellia sinensis and Seed-Extract from Casia tora on Viability of Mutans Streptococci isolated from the interface between orthodontic brackets and tooth surfaces.
Sung Hoon LIM ; Jeong Soon SEO ; Young Jooh YOON ; Kwang Won KIM ; So Young YOO ; Hwa Sook KIM ; Joong Ki KOOK ; Byoung Rai LEE ; Jong Hee CHA ; Jae Yoon PARK
Korean Journal of Orthodontics 2003;33(5):381-389
Mutans streptococci is the major causative factor in dental caries. Especially, orthodontic patients with fixed appliance are a risk group for dental caries. Because fixed appliances attached on teeth may change the environment of dental plaque, the enamel decalcification or dental caries around the bracket and band is a major side effect of orthodontic treatment. The aim of this study was to search plant extracts that have antimicrobial effect on mutans streptococci. Seed-extract of Casia tora were prepared with ethanol and CHMC-2032, the leaf-extracts from Camellia sinensis extract, was obtained extract, 2 type strains and 20 clinical isolates of mutans streptococci isolated from the interface between orthodontic brackets and tooth surfaces in the orthodontic patients were used in this study. The minimal inhibitory concentration of CHMC-2032 was 5 mg/ml on the S. mutans KCTC 3065, S. sobrinus KCTC 3088, and 8 clinical isolates of S. sobrinus. However, there was no antibacterial effect of seed-extract of C. tora on mutans streptococci. These data suggest that green tea may be more effective than the tea prepared from C. tora in the prevention of enamel decalcification or dental caries around brackets.
Camellia sinensis*
;
Camellia*
;
Dental Caries
;
Dental Enamel
;
Dental Plaque
;
Ethanol
;
Humans
;
Orthodontic Brackets*
;
Plant Extracts
;
Tea
;
Tooth*
5.Dural Arteriovenous Fistula Manifested as Transient Global Amnesia
Seulgi CHOI ; Soo Ji YOON ; Soo Im JANG ; Saenal LEE ; Ji Yoon ANN ; Eun Ja LEE ; Sung-Ho WOO ; Kwang Ki KIM ; Hang-Rai KIM
Journal of the Korean Neurological Association 2024;42(2):179-182
Unruptured dural arteriovenous fistula (dAVF) manifests various symptoms including exophthalmos, headache, tinnitus, and retro-orbital pain. Transient global amnesia (TGA) is a clinical syndrome of reversible anterograde amnesia. Here, we report a 62-year-old woman with dAVF, manifested as TGA. This case emphasized that the clinicians should stay vigilance to the organic cause of TGA, especially in those complaining other symptoms besides amnesia such as pulsatile tinnitus and headache. Furthermore, our case supports a hypothetical patho-mechanism of venous congestion for TGA.