1.A case of immune thrombocytopenic purpura with prolonged aPTT time: A clotter hidden in a bleeder?
Lee Mei HAN ; Khoo Pei JIE ; Gew Lai TECK ; Ng Chen FEI
The Medical Journal of Malaysia 2017;72(6):365-366
We report the case of a 23-year-old woman who presentedwith prolonged menstruation and multiple bruises on thelimbs and trunk. Investigations revealed severethrombocytopenia and deranged coagulation profile withmarkedly prolonged activated partial thromboplastin time(aPTT). Lupus anticoagulant, anti-cardiolipin antibody andanti-beta-2-glycoprotein 1 antibody were positive. She wasdiagnosed with Immune Thrombocytopenic Purpura (ITP)with positive antiphospholipid antibody serology and givena course of intravenous methylprednisolone and taperingdoses of oral prednisolone. She was steroid free and had nobleeding or thrombotic event over two years follow up.
2.Urinary trypsin inhibitor attenuates lipopolysaccharide-induced neutrophil activation.
Seong Heon LEE ; Hwi Jin KIM ; Hui Jing HAN ; Mei LI ; Sang Hyun KWAK ; Sanghee PARK
Korean Journal of Anesthesiology 2012;63(6):540-546
BACKGROUND: Urinary trypsin inhibitor (UTI), which is speculated to have anti-inflammatory effects, is one of serine protease inhibitors found in human urine and blood. The present study was conducted to clarify the effect of urinary trypsin inhibitor (UTI) on human neutrophil activation and its intracellular signaling mechanism in vitro. METHODS: To assess the possible interactions between UTI and lipopolysaccharide (LPS) in neutrophil activation, neutrophils from human blood were incubated with varying concentrations of UTI (1, 10, 100, 1,000 and 10,000 U/ml) plus LPS (100 ng/ml) or LPS alone in 24-well plates (5 x 106 cells/well). We measured protein levels for interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-alpha) using enzyme-linked immunosorbent assay (ELISA) kits after 4 hours of incubation period. To elucidate the intracellular signaling pathway, we also measured the levels of phosphorylation of p38, ERK1/2 and JNK via Western blot analysis. Moreover, the nuclear levels of nuclear factor-kappa B (NF-kappaB) were determined with electrophoretic mobility shift assays (EMSA). RESULTS: UTI decreased the expression of inflammatory cytokines, including TNF-alpha and IL-6, and activation of intracellular signaling pathways, such as JNK, but not P38, ERK1/2 and nuclear translocation of NF-kappaB. CONCLUSIONS: UTI can attenuate LPS-induced neutrophil responses and may partially contribute to the treatment of neutrophil-mediated inflammatory diseases.
Blotting, Western
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Cytokines
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Electrophoretic Mobility Shift Assay
;
Enzyme-Linked Immunosorbent Assay
;
Glycoproteins
;
Humans
;
Interleukin-6
;
Interleukins
;
Mitogen-Activated Protein Kinases
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Neutrophil Activation
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Neutrophils
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Phosphorylation
;
Serine Proteinase Inhibitors
;
Trypsin
;
Tumor Necrosis Factor-alpha
3.c-fos Expression in Bladder-Specific Spinal Neurons after Spinal Cord Injury Using Pseudorabies Virus.
Young Jae IM ; Chang Hee HONG ; Mei Hua JIN ; Bong Hee LEE ; Sang Won HAN
Yonsei Medical Journal 2008;49(3):479-485
PURPOSE: c-fos expression in spinal neurons that are activated by lower urinary tract stimulation are not organ specific. In this experiment, we demonstrated changes of c-fos expression in bladder-specific preganglionic neurons (PGNs) and interneurons using pseudorabies virus (PRV). MATERIALS AND METHODS: Forty Sprague-Dawley rats were used. We identified the neuronal pathway associated with the bladder by injecting PRV into the detrusor. An immunohistochemical method was used to stain Fos-protein encoded by the c-fos gene. Immunofluorescent staining for PRV was performed to evaluate changes in bladder-specific spinal neurons. RESULTS: Immunofluorescent staining with choline acetyltransferase (ChAT) revealed that the sacral parasympathetic nucleus (SPN) regions contained 9.8 PGNs/ section. In rats with chronic spinal cord injury by intravesical saline instillation, 82.4+/-10.3% of PGNs in SPN exhibited Fos-immunoreactive (IR). Two and a half days after PRV infection, PRV-IR PGNs were observed at 5.4 PGNs/ section, and 2.7+/-1.6% of them exhibited Fos-IR. Unlike ChAT-IR PGNs, PRV-IR PGNs are bladder-specific neurons and PRV-IR and Fos-IR cells found in the back of PRV-IR PGNs are bladder- specific interneurons. Three days after PRV infection, we observed many PRV-IR and Fos-IR cells in the dorsal commissure. These neurons are interneurons distributed in the bladder. CONCLUSION: We confirmed that in chronic spinal cord injury, the patterns of c-fos expression in bladder-specific spinal neurons were similar to those in voiding-reflex related spinal neurons, which had already been demonstrated earlier. We believe that our methodology can be applied to study interactions between voiding and other organs as well, such as the urethra and prostate.
Animals
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Female
;
Herpesvirus 1, Suid/*physiology
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Immunohistochemistry
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Interneurons/cytology/metabolism
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Neurons/cytology/*metabolism
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Proto-Oncogene Proteins c-fos/*metabolism
;
Rats
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Rats, Sprague-Dawley
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Spinal Cord Injuries/*physiopathology
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Urinary Bladder/cytology/*metabolism/virology
4.The maintenance ability and Ca²⁺ availability of skeletal muscle are enhanced by sildenafil.
Mei HUANG ; Keon Jin LEE ; Kyung Jin KIM ; Mi Kyoung AHN ; Chung Hyun CHO ; Do Han KIM ; Eun Hui LEE
Experimental & Molecular Medicine 2016;48(12):e278-
Sildenafil relaxes vascular smooth muscle cells and is used to treat pulmonary artery hypertension as well as erectile dysfunction. However, the effectiveness of sildenafil on skeletal muscle and the benefit of its clinical use have been controversial, and most studies focus primarily on tissues and organs from disease models without cellular examination. Here, the effects of sildenafil on skeletal muscle at the cellular level were examined using mouse primary skeletal myoblasts (the proliferative form of skeletal muscle stem cells) and myotubes, along with single-cell Ca2+ imaging experiments and cellular and biochemical studies. The proliferation of skeletal myoblasts was enhanced by sildenafil in a dose-independent manner. In skeletal myotubes, sildenafil enhanced the activity of ryanodine receptor 1, an internal Ca2+ channel, and Ca2+ movement that promotes skeletal muscle contraction, possibly due to an increase in the resting cytosolic Ca2+ level and a unique microscopic shape in the myotube membranes. Therefore, these results suggest that the maintenance ability of skeletal muscle mass and the contractility of skeletal muscle could be improved by sildenafil by enhancing the proliferation of skeletal myoblasts and increasing the Ca2+ availability of skeletal myotubes, respectively.
Animals
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Cytosol
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Erectile Dysfunction
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Hypertension
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Maintenance*
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Male
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Membranes
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Mice
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Muscle Fibers, Skeletal
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Muscle, Skeletal*
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Muscle, Smooth, Vascular
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Myoblasts, Skeletal
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Pulmonary Artery
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Ryanodine Receptor Calcium Release Channel
;
Sildenafil Citrate*
5.The Effect of Acetylcholine on the Potassium Currents and Length of Outer Hair Cell.
Hyong Ho CHO ; Joon Kyue LEE ; Jae Hong LEE ; Myung Joo JANG ; Mei HUANG ; Han Seong JEONG ; Yong Bum CHO ; Jong Seong PARK
Korean Journal of Otolaryngology - Head and Neck Surgery 2005;48(2):153-157
BACKGROUND AND OBJECTIVES: Inner hair cells (IHCs) of the organ of Corti change the external sound stimulus into the electrical signal and transmit this signal to the auditory cortex through afferent nerve fibers. Outer hair cells (OHCs) control the sound transmission function of IHC. OHCs respond with a somatic shape change to alterations in their membrane potential and this electromotile response is believed to provide mechanical feedback to the basilar membrane. Efferent nerve fibers which arise from the superior olivary nucleus in the midbrain and transmit to OHCs through medial olivocochlear bundle use acetylcholine (ACh) as a neurotransmitter. The cholinergic response of OHCs' alpha-9 nicotinic ACh receptor increase the Ca2+ influx, which control OHCs' electromotility by changing a membrane potential. In this research, the effect of ACh on the K+ current in OHC of guinea pig was studied, and the change of OHC length by ACh was studied. MATERIALS AND METHODS: Using the extracted OHC from a guinea pig potassium currents induced by ACh were recorded using the whole-cell patch clamp technique. The change of OHC length when ACh was applied was observed. RESULTS: 1) ACh increases voltage-dependent K+ current in OHC. 2) In the condition, which Ca2+-dependent K+ current is blocked by removing Ca2+ from intra-cellular fluid, ACh has no effect on K+ current in OHC. 3) ACh increases OHC length. CONCLUSION: These experimental results show that ACh from the medial olivocochlear efferent system regulates mobility of OHC, increases the Ca2+-dependent K+ currents in OHC.
Acetylcholine*
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Animals
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Auditory Cortex
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Basilar Membrane
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Calcium
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Guinea Pigs
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Hair*
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Membrane Potentials
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Mesencephalon
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Nerve Fibers
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Neurotransmitter Agents
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Olivary Nucleus
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Organ of Corti
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Potassium Channels
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Potassium*
6.Prospective audit of post-chemotherapy febrile neutropenia in patients with solid cancer and lymphoma in two Singaporean cancer centres.
Mabel WONG ; Jing JIN ; Min Han TAN ; Yee Mei LEE ; Ten Eng LEE ; Ying DING ; Hong Chan YONG ; Siew Eng LIM ; Louis Ya CHAI ; Noan Minh CHAU ; Li Yang HSU
Annals of the Academy of Medicine, Singapore 2012;41(7):287-293
INTRODUCTIONFebrile neutropenia (FN) is a significant cause of mortality and morbidity in oncology and haematology units worldwide. The overall mortality in hospital surveys in Singapore surveys on post-chemotherapy FN has ranged between 3.0% and 8.8%. However, recent evidence indicates that outpatient management of patients with low-risk FN is safe and cost-effective.
MATERIALS AND METHODSWe conducted a prospective audit on a cohort of adult patients with post-chemotherapy FN seen at 2 local public sector cancer centres over a 1-year period in order to define their epidemiological characteristics and outcomes, and also to assess the uptake of early discharge/outpatient management strategies for these patients.
RESULTSWe reviewed 306 FN episodes from 248 patients. Patient characteristics and outcomes were similar between both institutions. Eleven (3.7%) FN episodes were managed as outpatient and none developed complications. Overall 30-day mortality was 6.6%, while the median length of stay (LOS) was 7 days (IQR: 4 to 11 days). The only independent risk factor for mortality was severe sepsis (OR:13.19; 95% CI: 1.98 to 87.7; P = 0.008). Factors independently associated with a longer LOS were vancomycin prescription (coefficient: 0.25; 95% CI: 0.08 to 0.41; P = 0.003), longer duration of intravenous antibiotics (coefficient: 0.08; 95% CI: 0.06 to 0.10; P <0.001), and prior review by an infectious diseases physician (coefficient: 0.16; 95% CI: 0.01 to 0.31; P = 0.034).
CONCLUSIONThis audit demonstrated that mortality from FN in our 2 cancer centres is low and comparable to international institutions. It also demonstrates that outpatient management of FN is safe in selected patients, and can be further expanded for right-siting of resources.
Adult ; Anti-Bacterial Agents ; therapeutic use ; Antineoplastic Agents ; adverse effects ; Bacterial Infections ; epidemiology ; Cohort Studies ; Female ; Fever ; epidemiology ; etiology ; Humans ; Male ; Middle Aged ; Mycoses ; epidemiology ; Neoplasms ; complications ; drug therapy ; Neutropenia ; epidemiology ; etiology ; Prospective Studies ; Singapore ; epidemiology
7.Function of the Cold Receptor (TRPM8) Associated with Voiding Dysfunction in Bladder Outlet Obstruction in Rats.
Ji Hee JUN ; Hyo Jin KANG ; Mei Hua JIN ; Hye Young LEE ; Young Jae IM ; Hyun Jin JUNG ; Sang Won HAN
International Neurourology Journal 2012;16(2):69-76
PURPOSE: Bladder outlet obstruction (BOO) causes storage and voiding dysfunction in the lower urinary tract. We investigated the expression of transient receptor potential cation channel subfamily M member 8 (TRPM8) to evaluate the relationship between TRPM8 expression and overactive bladder (OAB) in a rat model of BOO. METHODS: Fifty female Sprague-Dawley rats were divided into 4 groups; normal (n=10), normal-menthol (n=10), BOO (n=15), BOO-menthol (n=15). After 3 weeks, cystometry was performed by infusing physiological saline and menthol (3 mM) into the bladder at a slow infusion rate. The histological changes and expression of TRPM8 in the bladder were investigated by Masson's trichrome staining, immunofluorescence and reverse transcription-polymerase chain reaction. RESULTS: Cystometry showed that the intercontraction interval (ICI; 428.2+/-23.4 vs. 880.4+/-51.2, P<0.001), micturition pressure (MP; 25.7+/-1.01 vs. 71.80+/-3.01, P<0.001), and threshold pressure (2.9+/-0.25 vs. 9.2+/-1.58, P<0.01) were significantly increased in BOO rats. The bladder wall was significantly dilated compared with the control. Detrusor muscle hypertrophy and a thick mucosa layer were observed in BOO bladder. After menthol treatment, ICIs were decreased and MPs were increased in the menthol treatment groups. TRPM8-positive cells and mRNA were predominantly increased in the bladder and dorsal root ganglia of all groups compared with the normal group. CONCLUSIONS: Increased bladder wall thickness and proportion of collagen probably affect voiding dysfunction. Furthermore, an increase of TRPM8 expression in BOO may induce entry of Ca2+ from the extracellular space or stores. The increase of Ca2+ probably causes contraction of smooth muscle in BOO. However, OAB symptoms were not observed after menthol treatment although the expression of TRPM8 was abundant in the bladder epithelium after menthol treatment. Although OAB in BOO models may be caused by complex pathways, regulation of TRPM8 presents possibilities for OAB treatment.
Animals
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Cold Temperature
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Collagen
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Contracts
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Epithelium
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Extracellular Space
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Female
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Fluorescent Antibody Technique
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Ganglia, Spinal
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Humans
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Hypertrophy
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Menthol
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Mucous Membrane
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Muscle, Smooth
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Muscles
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Rats
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Rats, Sprague-Dawley
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RNA, Messenger
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Urinary Bladder
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Urinary Bladder Neck Obstruction
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Urinary Bladder, Overactive
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Urinary Tract
;
Urination
8.Virtual Screening and Testing of GSK-3 Inhibitors Using Human SH-SY5Y Cells Expressing Tau Folding Reporter and Mouse Hippocampal Primary Culture under Tau Cytotoxicity
Chih-Hsin LIN ; Yu-Shao HSIEH ; Ying-Chieh SUN ; Wun-Han HUANG ; Shu-Ling CHEN ; Zheng-Kui WENG ; Te-Hsien LIN ; Yih-Ru WU ; Kuo-Hsuan CHANG ; Hei-Jen HUANG ; Guan-Chiun LEE ; Hsiu Mei HSIEH-LI ; Guey-Jen LEE-CHEN
Biomolecules & Therapeutics 2023;31(1):127-138
Glycogen synthase kinase-3β (GSK-3β) is an important serine/threonine kinase that implicates in multiple cellular processes and links with the neurodegenerative diseases including Alzheimer’s disease (AD). In this study, structure-based virtual screening was performed to search database for compounds targeting GSK-3β from Enamine’s screening collection. Of the top-ranked compounds, 7 primary hits underwent a luminescent kinase assay and a cell assay using human neuroblastoma SH-SY5Y cells expressing Tau repeat domain (TauRD) with pro-aggregant mutation ΔK280. In the kinase assay for these 7 compounds, residual GSK-3β activities ranged from 36.1% to 90.0% were detected at the IC50 of SB-216763. In the cell assay, only compounds VB-030 and VB-037 reduced Tau aggregation in SH-SY5Y cells expressing ΔK280 TauRD-DsRed folding reporter. In SH-SY5Y cells expressing ΔK280 TauRD, neither VB-030 nor VB-037 increased expression of GSK-3α Ser21 or GSK-3β Ser9. Among extracellular signal-regulated kinase (ERK), AKT serine/threonine kinase 1 (AKT), mitogen-activated protein kinase 14 (P38) and mitogenactivated protein kinase 8 (JNK) which modulate Tau phosphorylation, VB-037 attenuated active phosphorylation of P38 Thr180/ Tyr182, whereas VB-030 had no effect on the phosphorylation status of ERK, AKT, P38 or JNK. However, both VB-030 and VB-037 reduced endogenous Tau phosphorylation at Ser202, Thr231, Ser396 and Ser404 in neuronally differentiated SH-SY5Y expressing ΔK280 TauRD. In addition, VB-030 and VB-037 further improved neuronal survival and/or neurite length and branch in mouse hippocampal primary culture under Tau cytotoxicity. Overall, through inhibiting GSK-3β kinase activity and/or p-P38 (Thr180/Tyr182), both compounds may serve as promising candidates to reduce Tau aggregation/cytotoxicity for AD treatment.
9.Fucodiphlorethol G Purified from Ecklonia cava Suppresses Ultraviolet B Radiation-Induced Oxidative Stress and Cellular Damage.
Ki Cheon KIM ; Mei Jing PIAO ; Jian ZHENG ; Cheng Wen YAO ; Ji Won CHA ; Madduma Hewage Susara Ruwan KUMARA ; Xia HAN ; Hee Kyoung KANG ; Nam Ho LEE ; Jin Won HYUN
Biomolecules & Therapeutics 2014;22(4):301-307
Fucodiphlorethol G (6'-[2,4-dihydroxy-6-(2,4,6-trihydroxyphenoxy)phenoxy]biphenyl-2,2',4,4',6-pentol) is a compound purified from Ecklonia cava, a brown alga that is widely distributed offshore of Jeju Island. This study investigated the protective effects of fucodiphlorethol G against oxidative damage-mediated apoptosis induced by ultraviolet B (UVB) irradiation. Fucodiphlorethol G attenuated the generation of 2, 2-diphenyl-1-picrylhydrazyl radicals and intracellular reactive oxygen species in response to UVB irradiation. Fucodiphlorethol G suppressed the inhibition of human keratinocyte growth by UVB irradiation. Additionally, the wavelength of light absorbed by fucodiphlorethol G was close to the UVB spectrum. Fucodiphlorethol G reduced UVB radiation-induced 8-isoprostane generation and DNA fragmentation in human keratinocytes. Moreover, fucodiphlorethol G reduced UVB radiation-induced loss of mitochondrial membrane potential, generation of apoptotic cells, and active caspase-9 expression. Taken together, fucodiphlorethol G protected human keratinocytes against UVB radiation-induced cell damage and apoptosis by absorbing UVB radiation and scavenging reactive oxygen species.
Apoptosis
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Caspase 9
;
DNA Fragmentation
;
Humans
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Keratinocytes
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Membrane Potential, Mitochondrial
;
Oxidative Stress*
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Reactive Oxygen Species