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1.
ACS Appl Mater Interfaces ; 16(1): 594-604, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38114065

ABSTRACT

For stable battery operation of silicon (Si)-based anodes, utilizing cross-linked three-dimensional (3D) network binders has emerged as an effective strategy to mitigate significant volume fluctuations of Si particles. In the design of cross-linked network binders, careful selection of appropriate cross-linking agents is crucial to maintaining a balance between the robustness and functionality of the network. Herein, we strategically design and optimize a 3D cross-linked network binder through a comprehensive analysis of cross-linking agents. The proposed network is composed of poly(vinyl alcohol) grafted poly(acrylic acid) (PVA-g-PAA, PVgA) and aromatic diamines. PVgA is chosen as the polymer backbone owing to its high flexibility and facile synthesis using an ecofriendly water solvent. Subsequently, an aromatic diamine is employed as a cross-linker to construct a robust amide network that features a resonance-stabilized high modulus and enhanced adhesion. Comparative investigations of three cross-linkers, 2,2'-bis(trifluoromethyl)benzidine, 3,3'-oxidianiline, and 4,4'-oxybis[3-(trifluoromethyl)aniline] (TFODA), highlight the roles of the trifluoromethyl group (-CF3) and the ether linkage. Consequently, PVgA cross-linked with TFODA (PVgA-TFODA), featuring both -CF3 and -O-, establishes a well-balanced 3D network characterized by heightened elasticity and improved binding forces. The optimized Si and SiOx/graphite composite electrodes with the PVgA-TFODA binder demonstrate impressive structural stability and stable cycling. This study offers a novel perspective on designing cross-linked network binders, showcasing the benefits of a multidimensional approach considering chemical and physical interactions.

2.
Vaccine ; 41(19): 3106-3110, 2023 05 05.
Article in English | MEDLINE | ID: mdl-37055344

ABSTRACT

A recombinant protective antigen anthrax vaccine (GC1109) is being developed as a new-generation vaccine by the Korea Disease Control and Prevention Agency. In accordance with the ongoing step 2 of phase II clinical trials, the immunogenicity and protective efficacy of the booster dose of GC1109 were evaluated in A/J mice after 3 serial vaccinations at 4-week intervals. The results indicated that the booster dose significantly increased the production of anti-protective antigen (PA) IgG and toxin-neutralizing antibody (TNA) compared with those of the group without booster. An enhanced protective effect of the booster dose was not observed because the TNA titers of the group without booster were high enough to confer protection against spore challenge. Additionally, the correlation between TNA titers and probability of survival was determined for calculating the threshold TNA titer levels associated with protection. The threshold 50 % neutralization factor (NF50) of TNA showing 70 % probability of protection was 0.21 in A/J mice with 1,200 LD50 Sterne spores challenge. These results indicate that GC1109 is a promising candidate as a new-generation anthrax vaccine and that a booster dose might provide enhanced protection by producing toxin-neutralizing antibodies.


Subject(s)
Anthrax Vaccines , Anthrax , Bacillus anthracis , Mice , Animals , Antigens, Bacterial/genetics , Antibodies, Bacterial , Anthrax/prevention & control , Vaccines, Synthetic/genetics , Mice, Inbred Strains , Antibodies, Neutralizing
3.
Int J Mol Sci ; 23(17)2022 Aug 23.
Article in English | MEDLINE | ID: mdl-36076944

ABSTRACT

Alzheimer's disease (AD) is the most common age-related dementia. The alteration in metabolic characteristics determines the prognosis. Patients at risk show reduced glucose uptake in the brain. Additionally, type 2 diabetes mellitus increases the risk of AD with increasing age. Therefore, changes in glucose uptake in the cerebral cortex may predict the histopathological diagnosis of AD. The shifts in glucose uptake and metabolism, insulin resistance, oxidative stress, and abnormal autophagy advance the pathogenesis of AD syndrome. Here, we summarize the role of altered glucose metabolism in type 2 diabetes for AD prognosis. Additionally, we discuss diagnosis and potential pharmacological interventions for glucose metabolism defects in AD to encourage the development of novel therapeutic methods.


Subject(s)
Alzheimer Disease , Diabetes Mellitus, Type 2 , Insulin Resistance , Alzheimer Disease/metabolism , Brain/metabolism , Diabetes Mellitus, Type 2/metabolism , Glucose/metabolism , Humans
4.
Sensors (Basel) ; 22(4)2022 Feb 10.
Article in English | MEDLINE | ID: mdl-35214273

ABSTRACT

Medical supply chain communication networks engender critical information and data. Notably in the COVID era, inner personal and private information is being shared between healthcare providers regarding the medical supply chain. In recent years, multiple cyber-attacks have targeted medical supply chain communication networks due to their lack of security measures. In the era where cyber-attacks are cheaper and easier due to the computational power and various algorithms available for malicious uses, security, and data privacy requires intensive and higher measures. On the other hand, Information Hiding Techniques (IHT) compromise various advanced methods to hide sensitive information from being disclosed to malicious nodes. Moreover, with the support of Blockchain, IHT can bring higher security and the required privacy levels. In this paper, we propose the implementation of Blockchain and smart contract with the information hiding technique to enhance the security and privacy of data communication in critical systems, such as smart healthcare supply chain communication networks. Results show the feasibility of the framework using Hyperledger smart contract along with the desired security level.


Subject(s)
Blockchain , COVID-19 , Algorithms , Humans , Privacy , SARS-CoV-2
5.
ACS Appl Mater Interfaces ; 13(17): 19983-19991, 2021 May 05.
Article in English | MEDLINE | ID: mdl-33819008

ABSTRACT

Among various energy harvester paradigms, the simple cantilever-structured magneto-mechano-electric (MME) energy generator comprises a piezoelectric material laminated on a magnetostrictive metal plate and permanent magnets as proof mass, exhibiting excellent magnetic energy-harvesting performance. The current challenge in using MME energy harvesters is the mechano-electric coupling at the interface between the piezoelectric material and magnetostrictive metal layer, which depends significantly on the mechanical properties of the interfacial adhesive layer. In this study, the effects of four types of adhesive interfacial layers on the output power and environmental and fatigue resistances of MME harvesters are systematically investigated. An optimized MME energy generator with an adhesive interfacial layer of 18.8 µm thickness and elastic modulus of 3.1 GPa achieves colossal enhancement (∼300%) with a maximum output power density of 0.92 mW/cm2, while a 10 Oe (=10 G = 1 mT in air; 60 Hz) magnetic field is applied. In addition, the generator exhibits a robust endurance of continuous 108 fatigue cycles and excellent temperature stability in the range of -30 to 70 °C. The presented MME generator, which harvests stray magnetic energy reliably, is promising as a low-cost and efficient autonomous power source for Internet of Things devices, wireless sensor networks, and so on.

6.
Acta Radiol ; 62(1): 113-119, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32312101

ABSTRACT

BACKGROUND: Cerebral angiography in a rabbit model is widely used in the field of interventional radiology. Conventionally, the femoral artery is used for cerebral angiography in radiology departments. However, angiographic studies require surgical cutdown of the femoral artery, which is technically difficult. PURPOSE: To evaluate a new cerebral angiography technique involving a transauricular approach in a rabbit model. MATERIAL AND METHODS: In each of 10 rabbits, central auricular arteries were punctured in the right or left ear with a 20-gauge i.v. catheter. A microcatheter (2.0 F) with a 0.016-inch guide wire was introduced through the i.v. catheter and advanced to the aortic arch. The microcatheter and guide wire were advanced selectively into cerebral arteries and angiography was performed. RESULTS: Central auricular arteries were successfully punctured with 20-gauge i.v. catheters. After approaching the aortic arch, microcatheter tips and guide wires were advanced manually to cerebral arteries on both sides. Difficulties in selecting the carotid arteries were resolved by using a looping technique within the cardiac chamber. Microcatheter loops within the cardiac chamber disappeared or remained during artery superselection. CONCLUSION: Transauricular cerebral angiography appears to be a feasible technique for brain or carotid intervention studies in rabbits. In addition, vertebral angiography using a transauricular approach is possible using the looping technique. Selection of carotid or vertebral arteries on each side was not difficult when the microcatheter and guide wire were looped within the cardiac chamber. The ear chosen for the initial puncture does not appear to be important.


Subject(s)
Cerebral Angiography/methods , Ear/blood supply , Animals , Arteries , Models, Animal , Rabbits
7.
Sci Rep ; 10(1): 9930, 2020 06 18.
Article in English | MEDLINE | ID: mdl-32555285

ABSTRACT

Due to its regulation of CDK1/2 phosphorylation, WEE1 plays essentially roles in the regulations of G2/M checkpoint and DNA damage response (DDR). WEE1 inhibition can increase genomic instability by inducing replication stress and G2/M checkpoint inactivation, which result in increased cellular sensitivity to DNA damaging agents. We considered an increase in genomic instability induced by WEE1 inhibition might be used to augment the effects of drugs targeting DNA repair protein. Typically, PARP inhibitors are effective in germline BRCA 1/2 mutated breast and ovarian cancer, but their applicabilities in triple-negative breast cancer (TNBC) are limited. This study was conducted to investigate the anti-tumor effects of the WEE1 inhibitor, AZD1775, and the mechanism responsible for its potentiation of sensitivity to olaparib (a PARP inhibitor) via the modulation of DDR in TNBC cells. Our results suggest that AZD1775 could be used to broaden the application range of olaparib in TNBC and provide a rationale for a clinical trial of combined olaparib and AZD1775 therapy.


Subject(s)
Cell Cycle Proteins/antagonists & inhibitors , DNA Damage , Drug Resistance, Neoplasm/drug effects , Gene Expression Regulation, Neoplastic , Phthalazines/pharmacology , Piperazines/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Triple Negative Breast Neoplasms/drug therapy , Animals , Apoptosis , Cell Cycle , Cell Proliferation , DNA Repair , Drug Synergism , Enzyme Inhibitors/pharmacology , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Pyrazoles/pharmacology , Pyrimidinones/pharmacology , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
8.
Oxid Med Cell Longev ; 2019: 2860642, 2019.
Article in English | MEDLINE | ID: mdl-31379987

ABSTRACT

Phosphatidylcholine is one of the major phospholipids comprising cellular membrane and is known to have several health-promoting activities, including the improvement of brain function and liver repair. In this paper, we examine the in vivo effect of dietary supplementation with phosphatidylcholine on the response to environmental stressors and aging in C. elegans. Treatment with phosphatidylcholine significantly increased the survival of worms under oxidative stress conditions. However, there was no significant difference in response to stresses caused by heat shock or ultraviolet irradiation. Oxidative stress is believed to be one of the major causal factors of aging. Then, we examined the effect of phosphatidylcholine on lifespan and age-related physiological changes. Phosphatidylcholine showed a lifespan-extending effect and a reduction in fertility, possibly as a tradeoff for long lifespan. Age-related decline of motility was also significantly delayed by supplementation with phosphatidylcholine. Interestingly, the expressions of well-known longevity-assuring genes, hsp-16.2 and sod-3, were significantly upregulated by dietary intervention with phosphatidylcholine. DAF-16, a transcription factor modulating stress response genes, was accumulated in the nucleus by phosphatidylcholine treatment. Increase of the ROS level with phosphatidylcholine suggests that the antioxidant and lifespan-extending effects are due to the hormetic effect of phosphatidylcholine. Phosphatidylcholine also showed a protective effect against amyloid beta-induced toxicity in Alzheimer's disease model animals. Experiments with long-lived mutants revealed that the lifespan-extending effect of phosphatidylcholine specifically overlapped with that of reduced insulin/IGF-1-like signaling and required DAF-16. These findings showed the antioxidant and antiaging activities of phosphatidylcholine for the first time in vivo. Further studies focusing on the identification of underlying cellular mechanisms involved in the antiaging effect will increase the possibility of using phosphatidylcholine for the development of antiaging therapeutics.


Subject(s)
Amyloid beta-Peptides/toxicity , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/drug effects , Forkhead Transcription Factors/metabolism , Longevity/drug effects , Phosphatidylcholines/pharmacology , Animals , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/radiation effects , Caenorhabditis elegans Proteins/antagonists & inhibitors , Caenorhabditis elegans Proteins/genetics , Cell Nucleus/metabolism , Forkhead Transcription Factors/antagonists & inhibitors , Forkhead Transcription Factors/genetics , Insulin/metabolism , Insulin-Like Growth Factor I/metabolism , Oxidative Stress/drug effects , RNA Interference , RNA, Double-Stranded/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Ultraviolet Rays , Up-Regulation/drug effects
9.
J Chem Neuroanat ; 98: 27-40, 2019 07.
Article in English | MEDLINE | ID: mdl-30951822

ABSTRACT

Recently, there have been reports that chronic insomnia acts as an insult in the brain, causing memory loss through the production of ROS, inflammation, and, Alzheimer's disease if persistent. Insomnia remains the leading cause of sleep disturbance and as such has serious implications for public health. Patients with Alzheimer's disease are also known to suffer from severe sleep disturbance. Meanwhile, vitexin is a key ingredient in Passiflora incarnata L (passion flower, PF) extract, which is known to help with sleep. This medicinal plant has been used as a folk remedy for sedation, anxiety and sleep since centuries ago, but the standardization work has not been done and the extent of the effect has not been clearly demonstrated. For this reason, we tried to test the possibility that repeated administration of PF could improve the memory by promoting hippocampal neurogenesis at the DBA/2 mice known have inherited sleep disorders, as well as preventive effects of Alzheimer's disease. Here, we found that vitexin, which is the main bioactive component of ethanol extracts from leaves and fruits (ratio; 8:2) of PF, confirmed the improvement of neurogenesis (DCX) of DBA/2 mice repeated PF oral administration by immunohistochemistry (IHC) and western blot analysis. PF-treated group showed increased the neurotrophic factor (BDNF) in the hippocampus compared with that of vehicle-treated group, but the inflammation markers Iba-1 (microglial marker) and COX-2 were inconsistent between the groups. However, we found COX-2 signal is essential for hippocampal neurogenesis according to the additional IHC experiments using COX-2 inhibitor and pIkappaB have shown. In addition, although prescription sleeping pills have been reported to show significant changes in appetite and metabolic rate from time to time, no changes in the feeding behavior, body weight, metabolic rate and body composition of the animals were observed by administration of PF. Interestingly, we found that short-term oral administration of PF displayed improved memory according to the water maze test. Quantitative analysis of Tau protein, which is a marker of Alzheimer's disease, was performed in the SD rats and DBA/2 mice by repeated PF oral administration and pTau/Tau values were significantly decreased in PF-treated group than vehicle-treated group. In conclusion, our results suggest that PF lead high hippocampal neurogenesis in the animals even in inherited sleep-disturbed animals. The increased hippocampal neurogenesis functionally enhanced memory and learning functions by repeated PF oral administration. These results identify PF as a potential therapy for enhancing memory functions and prevention of Alzheimer's disease through actions on the hippocampus.


Subject(s)
Memory/drug effects , Neurogenesis/drug effects , Passiflora , Plant Extracts/pharmacology , Sleep Wake Disorders , Animals , Doublecortin Protein , Hippocampus/drug effects , Male , Mice , Mice, Inbred DBA , Mice, Inbred ICR , Rats , Rats, Sprague-Dawley
10.
Anim Cells Syst (Seoul) ; 23(1): 18-25, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30834155

ABSTRACT

ß2-Adrenergic receptor (ß2-AR) is implicated in muscle metabolic activities such as glycogen metabolism, glucose uptake, lipolysis and muscle growth. However, the functional role of ß2-AR in the differentiation of skeletal muscle is largely unknown. Here, we examined the functional role of ß2-AR in L6 myoblast differentiation using the long-term-acting ß2-AR-specific agonist formoterol. We observed that formoterol treatment strongly suppressed L6 myoblast differentiation and the expression of myosin heavy chain (MHC) in a dose- and time-dependent manner. Showing that both long-acting agonist (formoterol) and short-acting agonist (terbutaline) inhibited the induction of MHC protein, whereas ß2-AR antagonist (ICI-118,551) upregulated MHC expression, we clearly demonstrated that ß2-AR is involved in L6 myoblast differentiation. Furthermore, our pharmacological inhibition study revealed that the PI3K-AKT pathway is the main signaling pathway for myotube formation. Formoterol inhibited the activation of PI3K-AKT signaling, but not that of ERK signaling. Moreover, formoterol selectively inhibited AKT activation by IGF-I, but not by insulin. Collectively, our findings reveal a previously undocumented role of ß2-AR activation in modulating the differentiation of L6 myoblasts.

11.
Cancer Res Treat ; 51(2): 451-463, 2019 Apr.
Article in English | MEDLINE | ID: mdl-29879757

ABSTRACT

PURPOSE: Pim kinases are highly conserved serine/threonine kinases, and different expression patterns of each isoform (Pim-1, Pim-2, and Pim-3) have been observed in various types of human cancers, including gastric cancer. AZD1208 is a potent and selective inhibitor that affects all three isoforms of Pim. We investigated the effects of AZD1208 as a single agent and in combination with an Akt inhibitor in gastric cancer cells. MATERIALS AND METHODS: The antitumor activity of AZD1208 with/without an Akt inhibitor was evaluated in a large panel of gastric cancer cell lines through growth inhibition assays. The underlying mechanism was also examined by western blotting, immunofluorescence assay, and cell cycle analysis. RESULTS: AZD1208 treatment decreased gastric cancer cell proliferation rates and induced autophagy only in long-term culture systems. Light chain 3B (LC3B), a marker of autophagy, was increased in sensitive cells in a dose-dependent manner with AZD1208 treatment, which suggested that the growth inhibition effect of AZD1208 was achieved through autophagy, not apoptosis. Moreover, we found that cells damaged by Pim inhibition were repaired by activation of the DNA damage repair pathway, which promoted cell survival and led the cells to become resistant to AZD1208. We also confirmed that the combination of an Akt inhibitor with AZD1208 produced a highly synergistic effect in gastric cancer cell lines. CONCLUSION: Treatment with AZD1208 alone induced considerable cell death through autophagy in gastric cancer cells. Moreover, the combination of AZD1208 with an Akt inhibitor showed synergistic antitumor effects through regulation of the DNA damage repair pathway.


Subject(s)
Biphenyl Compounds/pharmacology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , Thiazolidines/pharmacology , Autophagy/drug effects , Biphenyl Compounds/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , DNA Damage/drug effects , Drug Resistance, Neoplasm/drug effects , Drug Synergism , Humans , Isoenzymes/antagonists & inhibitors , Phosphorylation , Protein Kinase Inhibitors/chemistry , Stomach Neoplasms/metabolism , Thiazolidines/chemistry
12.
Mol Med Rep ; 18(6): 5389-5398, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30365103

ABSTRACT

Selenocysteine, a sulfur­containing amino acid, can modulate cellular oxidative stress defense systems by incorporating into anti­oxidant enzymes such as glutathione peroxidase and thioredoxin reductase. Selenocysteine can also prevent cancer, neurodegenerative diseases and cardiovascular diseases. A recent study revealed that dietary supplementation with selenocysteine can increase the resistance of Caenorhabditis elegans to environmental stressors and its lifespan. The objective of the present study was to identify the underlying mechanism involved in the lifespan­extending effect of selenocysteine and the effect of selenocysteine on age­associated pathophysiological changes. Lifespan assays with known long­lived mutants of age­1 (the ortholog of the phosphoinositide 3-kinase), clk­1 (the ortholog of demethoxyubiquinone hydroxylase) and eat­2 (a ligand-gated ion channel subunit) revealed that the effect of selenocysteine on lifespan specifically overlapped with that of the eat­2 mutation, a genetic model of dietary restriction (DR). Selenocysteine mimicked the effect of DR on the bacterial dilution method. It required SKN-1 (the ortholog of mammalian nuclear factor-erythroid-related factor) for lifespan extension. In addition, selenocysteine significantly delayed the paralysis induced by human amyloid­ß gene, positively correlated with the incidence of Alzheimer's disease. The effect of selenocysteine on amyloid­ß­induced toxicity was dependent on the nuclear localization of DAF­16. Reduced survival caused by high­glucose­diet was recovered by selenocysteine. Selenocysteine also reduced the cellular level of reactive oxygen species known to be increased by high­glucose­diet. The results of the present study suggested that selenocysteine can mimic the effect of DR on lifespan and age­associated pathophysiological alterations, providing scientific evidence for the development of DR mimetics using selenocysteine.


Subject(s)
Aging , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/physiology , Caloric Restriction , Longevity/drug effects , Selenocysteine/pharmacology , Aging/drug effects , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/metabolism , Animals , Biomarkers , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Dose-Response Relationship, Drug , Glucose/metabolism , Humans , Mutation , Oxidative Stress/drug effects , Protein Transport , Reactive Oxygen Species/metabolism
13.
Clinics (Sao Paulo) ; 72(8): 491-498, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28954009

ABSTRACT

OBJECTIVE:: The free radical theory of aging suggests that cellular oxidative damage caused by free radicals is a leading cause of aging. In the present study, we examined the effects of a well-known anti-oxidant amino acid derivative, selenocysteine, in response to environmental stress and aging using Caenorhabditis elegans as a model system. METHOD:: The response to oxidative stress induced by H2O2 or ultraviolet irradiation was compared between the untreated control and selenocysteine-treated groups. The effect of selenocysteine on lifespan and fertility was then determined. To examine the effect of selenocysteine on muscle aging, we monitored the change in motility with aging in both the untreated control and selenocysteine-treated groups. RESULTS:: Dietary supplementation with selenocysteine significantly increased resistance to oxidative stress. Survival after ultraviolet irradiation was also increased by supplementation with selenocysteine. Treatment with selenocysteine confers a longevity phenotype without an accompanying reduction in fertility, which is frequently observed in lifespan-extending interventions as a trade-off in C. elegans. In addition, the age-related decline in motility was significantly delayed by supplementation of selenocysteine. CONCLUSION:: These findings suggest that dietary supplementation of selenocysteine can modulate response to stressors and lead to lifespan extension, thus supporting the free radical theory of aging.


Subject(s)
Aging/drug effects , Antioxidants/pharmacology , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/physiology , Oxidative Stress/drug effects , Selenocysteine/pharmacology , Age Factors , Animals , Caenorhabditis elegans/radiation effects , Fertility/drug effects , Locomotion/drug effects , Longevity/drug effects , Reproducibility of Results , Reproduction/drug effects , Stress, Physiological/drug effects , Time Factors
14.
Clinics ; 72(8): 491-498, Aug. 2017. tab, graf
Article in English | LILACS | ID: biblio-890723

ABSTRACT

OBJECTIVE: The free radical theory of aging suggests that cellular oxidative damage caused by free radicals is a leading cause of aging. In the present study, we examined the effects of a well-known anti-oxidant amino acid derivative, selenocysteine, in response to environmental stress and aging using Caenorhabditis elegans as a model system. METHOD: The response to oxidative stress induced by H2O2 or ultraviolet irradiation was compared between the untreated control and selenocysteine-treated groups. The effect of selenocysteine on lifespan and fertility was then determined. To examine the effect of selenocysteine on muscle aging, we monitored the change in motility with aging in both the untreated control and selenocysteine-treated groups. RESULTS: Dietary supplementation with selenocysteine significantly increased resistance to oxidative stress. Survival after ultraviolet irradiation was also increased by supplementation with selenocysteine. Treatment with selenocysteine confers a longevity phenotype without an accompanying reduction in fertility, which is frequently observed in lifespan-extending interventions as a trade-off in C. elegans. In addition, the age-related decline in motility was significantly delayed by supplementation of selenocysteine. CONCLUSION: These findings suggest that dietary supplementation of selenocysteine can modulate response to stressors and lead to lifespan extension, thus supporting the free radical theory of aging.


Subject(s)
Animals , Aging/drug effects , Selenocysteine/pharmacology , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/physiology , Oxidative Stress/drug effects , Antioxidants/pharmacology , Reproduction/drug effects , Stress, Physiological/drug effects , Time Factors , Reproducibility of Results , Age Factors , Caenorhabditis elegans/radiation effects , Fertility/drug effects , Locomotion/drug effects , Longevity/drug effects
15.
Osong Public Health Res Perspect ; 2(2): 115-26, 2011 Sep.
Article in English | MEDLINE | ID: mdl-24159461

ABSTRACT

OBJECTIVES: To confirm genotype diversities of clinical isolates of Bordetella pertussis and to evaluate the risk of pertussis outbreak in Korea. METHODS: Seven housekeeping genes and 10 antigenic determinant genes from clinical B. pertussis isolates were analyzed by Multilocus sequence typing (MLST). RESULTS: More variant pattern was observed in antigenic determinant genes. Especially, PtxS1 gene was the most variant gene; five genotypes were observed from eight global genotypes. In the bacterial type, the number of observed sequence types in the isolates was seven and the most frequent form was type 1 (79.6%). This major sequence type also showed a time-dependent transition pattern. Older isolates (1968 and 1975) showed type 1 and 6 in housekeeping genes and antigenic determinant genes, respectively. However, these were changed to type 2 and 1 in isolates 1999-2008. This transition was mainly attributed to genotype change of PtxS1 and Fim3 gene; the tendency of genotype change was to avoid vaccine-derived genotype. In addition, there was second transition in 2009. In this period, only the sequence type of antigenic determinant genes was changed to type 2. Based Upon Related Sequence Types (BURST) analysis confirmed that there were two clonal complexes (ACCI and ACCII) in the Korean isolates. Moreover, the recently increased sequence type was revealed as AST2 derived from AST 3 in ACCI. CONCLUSIONS: Genotype changes in Korean distributing strains are still progressing and there was a specific driving force in antigenic determinant genes. Therefore continuous surveillance of genotype change of the distributing strains should be performed to confirm interrelationship of genotype change with vaccine immunity.

16.
Bioprocess Biosyst Eng ; 29(3): 163-8, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16802121

ABSTRACT

In plant cell culture, the delivery of nutrition and gas (mainly oxygen) to the cells is the most important factor for viability. In this paper, we propose a polydimethylsiloxane (PDMS)-based microculture system that is designed to have good aeration. PDMS is known to have excellent air permeability, and through the experimental method, we investigated the relation between the degree of air delivery and the thickness of the PDMS sheet covering the culture chamber. We determined the proper thickness of the cover sheet, and cultured protoplasts of Nicotiana tabacum in a culture chamber covered with a PDMS sheet having thickness of 400 microm. The cells were successfully divided, and lived well inside the culture chamber for 10 days. In addition, protoplasts were cultured inside the culture chambers covered with the cover glass and the PDMS sheet, respectively, and the microcolonies were formed well inside the PDMS covered chamber after 10 days.


Subject(s)
Air , Cell Culture Techniques/instrumentation , Dimethylpolysiloxanes/chemistry , Microfluidics/instrumentation , Nicotiana/growth & development , Protoplasts/physiology , Silicones/chemistry , Ultrafiltration/instrumentation , Cell Culture Techniques/methods , Cells, Cultured , Elasticity , Equipment Design , Equipment Failure Analysis , Materials Testing , Membranes, Artificial , Microfluidics/methods , Permeability , Protoplasts/cytology , Nicotiana/cytology , Ultrafiltration/methods
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