• Title/Summary/Keyword: Hair Cell

Search Result 275, Processing Time 0.025 seconds

Tricho-dento-osseous Syndrome Mutant Dlx3 Shows Lower Transactivation Potential but Has Longer Half-life than Wild-type Dlx3

  • Cha, Ji-Hun;Ryoo, Hyun-Mo;Woo, Kyung-Mi;Kim, Gwan-Shik;Baek, Jeong-Hwa
    • International Journal of Oral Biology
    • /
    • v.32 no.4
    • /
    • pp.119-125
    • /
    • 2007
  • Dlx3 is a homeodomain protein and is known to play a role in development and differentiation of many tissues. Deletion of four base pairs in DLX3 (NT3198) is causally related to tricho-dento-osseous (TDO) syndrome (OMIM #190320), a genetic disorder manifested by taurodontism, hair abnormalities, and increased bone density in the cranium. The molecular mechanisms that explain the phenotypic characteristics of TDO syndrome have not been clearly determined. In this study, we examined phenotypic characteristics of wild type DLX3(wtDlx3) and 4-BP DEL DLX3 (TDO mtDlx3) in C2C12 cells. To investigate how wtDlx3 and TDO mtDlx3 differentially regulate osteoblastic differentiation, reporter assays were performed by using luciferase reporters containing the promoters of alkaline phosphatase, bone sialoprotein or osteocalcin. Both wtDlx3 and TDO mtDlx3 enhanced significantly all the reporter activities but the effect of mtDlx3 was much weaker than that of wtDlx3. In spite of these differences in reporter activity, electrophoretic mobility shift assay showed that both wtDlx3 and TDO mtDlx3 formed similar amounts of DNA binding complexes with Dlx3 binding consensus sequence or with ALP promoter oligonucleotide bearing the Dlx3 binding core sequence. TDO mtDlx3 exhibits a longer half-life than wtDlx3 and it corresponds to PESTfind analysis result showing that potential PEST sequence was missed in carboxy terminal of TDO mtDlx3. In addition, co-immunoprecipitation demonstrated that TDO mtDlx3 binds to Msx2 more strongly than wtDlx3. Taken together, though TDO mtDlx3 acted as a weaker transcriptional activator than wtDlx3 in osteoblastic cells, there is possibility that during in vivo osteoblast differentiation TDO mtDlx3 may antagonize transcriptional repressor activity of Msx2 more effectively and for longer period than wtDlx3, resulting in enhancement of osteoblast differentiation.

A taxonomic study on six section subgenus Vigena Nees of Carex L. (Cyperaceae) in Korea (한국산 괭이사초아속(subgen. Vignea Nees) 6절의 분류 형질에 관한 연구)

  • Oh, Yong Cha;Jo, Mi Jung
    • Korean Journal of Plant Taxonomy
    • /
    • v.33 no.3
    • /
    • pp.227-253
    • /
    • 2003
  • Morphological characters of C. kobomugi, C. gibba, C. echinata. C. remotiuscula. C. maakii. C. curta, and C. loliacea of genus Carex were rexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters. such as length and width of stem and leaf, sheath, bract, spike, scale, perigynium, beak of perigynium, length of spike peduncle, size, and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynium, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns (fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae, prickle present/absent of perigynium and leaf were useful for the identification of observed seven taxa. Examined six taxa of section Macrocephalae, Gibbae, Stellulatae, Elongatae, Ovales, and Heleonates were distint from each other with respect of length and width stem, leaf, bract, perigynium, perigynium beak, lenght of spike peduncle, perigynium, and leaf. A key based on data was presented here.

Primary cilia in energy balance signaling and metabolic disorder

  • Lee, Hankyu;Song, Jieun;Jung, Joo Hyun;Ko, Hyuk Wan
    • BMB Reports
    • /
    • v.48 no.12
    • /
    • pp.647-654
    • /
    • 2015
  • Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organelle, the primary cilium, to metabolic disorder, obesity and type II diabetes. Primary cilia are microtubule based hair-like membranous structures, lacking motility and functions such as sensing the environmental cues, and transducing extracellular signals within the cells. Interestingly, the subclass of ciliopathies, such as Bardet-Biedle and Alström syndrome, manifest obesity and type II diabetes in human and mouse model systems. Moreover, studies on genetic mouse model system indicate that more ciliary genes affect energy homeostasis through multiple regulatory steps such as central and peripheral actions of leptin and insulin. In this review, we discuss the latest findings in primary cilia and metabolic disorders, and propose the possible interaction between primary cilia and the leptin and insulin signal pathways which might enhance our understanding of the unambiguous link of a cell's antenna to obesity and type II diabetes.

Safety Evaluation of Topical Valproate Application

  • Choi, Sun Young;Seop, Song Yi;Hyun, Moo Yeol;Yoo, Kwang Ho;Kim, Beom Joon;Kim, Myeung Nam;Cho, Jae-We
    • Toxicological Research
    • /
    • v.29 no.2
    • /
    • pp.87-90
    • /
    • 2013
  • The potential role of topical valproate (VPA) in hair regrowth has been recently suggested. However, safety reports of VPA as a topical formulation are lacking. Therefore, in the present study, we investigated whether VPA causes skin irritation in humans. We first performed a cell viability test and showed that VPA did not exhibit toxicity toward HaCaT keratinocytes, fibroblasts, and RBL-3H mast cells. We then performed clinical patch test and skin irritation test through transdermal drug delivery with the help of microneedle rollers. No significant findings were obtained in the clinical patch test. In the skin irritation test, only 1 patient showed erythema at 1 hr, but the irritation reaction faded away within a few hours. Erythema and edema were not observed at 24 hr. We concluded that VPA has minimal potential to elicit skin irritation. Therefore, we consider that VPA can safely be applied to human skin.

Topical Application of 0.1% Tacrolimus Ointment for Treatment of Sinus Refractory Pododermatitis Secondary to Atopy in a Dog

  • Kim, Ha-Jung;Yoo, Jong-Hyun;Park, Chul;Park, Hee-Myung
    • Journal of Veterinary Clinics
    • /
    • v.25 no.3
    • /
    • pp.202-206
    • /
    • 2008
  • An 8-year-old, castrated male Shih-tzu was referred due to relapsing pododermatitis and generalized pruritus. On physical examination, right forepaw showed swelling and serosanguinous exudates from sinus tract on dorsal paw. There were no remarkable findings on complete blood count (CBC), serum chemistry, and radiologic examination. On cytological examination of exudates from sinus tract, phagocyted bacteria and numerous degenerative neutrophils were noted. Results of deep skin scraping and plucking hair examination were unremarkable. Skin biopsy was performed and ruled out other skin diseases. Histopathology showed epidermal hyperplasia and diffuse mononuclear cell inflammation in dermal layer. Moreover, pyogranulomatous inflammation was demonstrated in subcutaneous layer. This case was clinically diagnosed as pododermatitis secondary to atopic dermatitis (AD). Clinical signs of pododermatitis were gradually improved following topical application of tacrolimus 0.1% ointment. This case report describes that tacrolimus ointment can be applicable for the treatment of refractory pododermatitis.

Idescarpin Isolated from the Fruits of Idesia polycarpa Inhibits Melanin Biosynthesis

  • Baek Seung-Hwa;Kim Dong-Hyun;Lee Chan-Yong;Kho Yung-Hee;Lee Choong-Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.5
    • /
    • pp.667-672
    • /
    • 2006
  • Tyrosinase is an enzyme that catalyzes the biosynthetic pathway of melanin pigments participating in the coloring of skin, hair, and eyes, and is widely distributed in nature. The inhibitory compounds of tyrosinase have been extensively used as a cosmetic agent with a skin-whitening effect. In this paper, several plant extracts were screened using Melan-a cells for the melanin biosynthesis inhibition activity, and Idesia polycarpa was selected. A melanin biosynthesis inhibitor was isolated from I. polycarpa fruits by activity-guided fractionation, and the inhibitor was identified as 6-hydroxy-2-[[[(1-hydroxy-6-oxo-2-cyclohexenl-yl)carbonyl]oxy]methyl]phenyl$\beta$-D-glucopyranoside (idescrapin) by comparing it with reported spectral data. Idescarpin $(IC_{50}=8{\mu}g/ml)$ reduced melanin content compared with the vehicle. In addition, the inhibitory activity of idescarpin for melanin synthesis is mediated by decreasing tyrosinase protein rather than directly inhibiting the tyrosinase activity. These results suggest that idescarpin isolated from I. polycarpa fruits may be used as a skin-whitening agent.

Performance Evaluation of Speech Onset Representation Characteristic of Cochlear Implants Speech Processor using Spike Train Decoding (Spike Train Decoding에 기반한 인공와우 어음처리기의 음성시작점 정보 전달특성 평가)

  • Kim, Doo-Hee;Kim, Jin-Ho;Kim, Kyung-Hwan
    • Journal of Biomedical Engineering Research
    • /
    • v.28 no.5
    • /
    • pp.694-702
    • /
    • 2007
  • The adaptation effect originating from the chemical synapse between auditory nerve and inner hair cell gives advantage in accurate representation of temporal cues of incoming speech such as speech onset. Thus it is expected that the modification of conventional speech processing strategies of cochlear implant(CI) by incorporating the adaptation effect will result in considerable improvement of speech perception performance such as consonant perception score. Our purpose in this paper was to evaluate our new CI speech processing strategy incorporating the adaptation effect by the observation of auditory nerve responses. By classifying the presence or absence of speech from the auditory nerve responses, i. e. spike trains, we could quantitatively compare speech onset detection performances of conventional and improved strategies. We could verify the effectiveness of the adaptation effect in improving the speech onset representation characteristics.

A Case of Pilomatricoma with Extensive Ossification Arising the Posterior Neck (후경부에 발생한 광범위 골화를 동반한 모기질종 1예)

  • Baek, Hun Hee;Hong, Seok Jung;Lee, Mi Ji;Kim, Seung Woo
    • Korean Journal of Head & Neck Oncology
    • /
    • v.32 no.1
    • /
    • pp.37-40
    • /
    • 2016
  • The pilomatricoma is a benign skin neoplasm arising from hair follicle matrix cells, and it comprises approximately 0.12% of all benign skin tumors. It occurs most commonly in head and neck. It usually tends to occur in childhood or school-age. Mainly, it exists in single subcutaneous or intradermal nodule and grows very slowly. The diagnosis is confirmed by histopathologic examination. Histopathologically, it is characterized by basaloid cells, enucleated shadow cells and calcifications in the shadow cell. However, it is rare to present extensive ossification in pilomatricoma. The treatment of choice is wide local excision. A 66-year-old man came to our clinic and he complained of two masses on right parotid tail and posterior neck. We performed excisional biopsy on posterior neck and partial parotidectomy. The pathology of former was pilomatricoma with extensive ossification. We report a rare unique case of pilomatricoma with brief review of literature.

Biomonitoring the Genotoxicity of Environmental Pollutants Using the Tradescantia Bioassay (환경 중 유전독성물질 검색을 위한 자주달개비 생물검정 기법의 적용연구)

  • 신해식
    • Proceedings of the Korea Society of Environmental Toocicology Conference
    • /
    • 2004.05a
    • /
    • pp.47-60
    • /
    • 2004
  • Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public from agents that can cause mutation and/or cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

  • PDF

Ultrastructural Study of Induced Otic Vesicle from Isolated Xenopus Presumptive Ectoderm (Xenopus 초기배의 이낭과 동물극분리배양에서 유도된 이낭간의 형태비교)

  • Yoon, Chun-Sik;Kim, Hong-Duck;Cheong, Seon-Woo
    • Applied Microscopy
    • /
    • v.27 no.2
    • /
    • pp.189-196
    • /
    • 1997
  • The ultrastrucures of Xenopus otic vesicle from normal embryo (st. 43) and induced otic vesicle from animal cap assay with Activin A were compared. Activin A was applied to the presumptive ectoderm at various concentrations for three days at $20^{\circ}C$. The results were almost identical to the reference studies, but it was found that the otic vesicle was induced at the concentration of 10 ng/ml in to)v rate. This otic vesicle may be secondarily induced by the neural tissue showed commonly at the concentration of 10 ng/ml. Otoliths were observed as three or four-axis crystaline bodies in the lumen of otic vesicle. In electron micrograph of the normal embryo, two kinds of microvilli were observed on the apical position of hair cells. One was small and common, the other was large-sized and sparsely distributed. In both cell of otic vesicle, mitochondria, golgi apparatus and multivesicular body were rich, so, they showed a lot of similarities in ultrastructure. However, the otolith was not found and microvilli were overexpressed in the otic vesicle induced by Activin A.

  • PDF