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BACKGROUND: This study aimed to understand the experiences of nurses working in the integrated nursing care service, a relatively recent addition to the Korean hospital infrastructure, to suggest ways in which to address their grievances and needs and improve their job satisfaction, thereby reducing turnover. METHODS: This study adopted a qualitative approach to explore subjects' vivid experiences. Data were collected through in-depth interviews with 17 nurses with over one year of experience working in integrated nursing care wards. The main question asked was "Can you describe your experiences in the integrated nursing care ward?" All interviews were recorded, transcribed, and analyzed using Colaizzi's method for phenomenological research. RESULTS: Six theme clusters were derived from the analysis: "distorted perceptions of the integrated nursing care ward," "challenges owing to distorted perceptions of the integrated nursing care ward," "loneliness and fighting alone," "being ridiculed," "practicing textbook holistic care," and "the satisfaction felt only in the integrated nursing care ward." For the overarching theme, we identified "Satisfaction in providing holistic care despite the challenges." CONCLUSIONS: While working in the integrated nursing care ward, nurses practiced holistic nursing care, which in turn built their self-esteem. However, they experienced greater levels of stress as a result of misinformation. Therefore, dissemination of accurate information is necessary to correct public misunderstandings of the integrated nursing care wards. Further, adequate compensation and support systems are needed to relieve the stress nurses felt because of such misunderstandings. Additionally, nurses should be motivated to continue to provide quality care for the patients and take pride in their work. Future research should explore the physical and mental concerns of nurses working in integrated care wards.
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INTRODUCTION: In South Korea, the number of multicultural families is steadily increasing. The purpose of the study was to examine and identify the process of adaptation of elderly women to foreign daughters-in-law in multicultural families in rural settings. METHOD: This is a qualitative study and applies a grounded theory method. Data were collected through individual in-depth interviews between February and April 2019, involving 15 elderly women with foreign daughters-in-law, and analyzed employing Corbin and Strauss's grounded theory. RESULTS: The results are demonstrated through the "Chaotic," "Resistive," "Exploratory," "Transitional," and "Receptive" periods, based on the flow of time. DISCUSSION: The findings contribute to the practice and intervention of multicultural nursing by examining the adaptation process and providing future direction on the adaptation of elderly women who are part of multicultural families.
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Família , Núcleo Familiar , Humanos , Feminino , Idoso , Teoria Fundamentada , República da Coreia , Pesquisa QualitativaRESUMO
The elderly population in South Korea is rapidly increasing. The elderly living in the community are looking for alternative and complementary methods to improve their healthy longevity and quality of life. This study aimed to examine the effects of Multicomponent Oriental Integrative Intervention on the cognitive function, health status, life satisfaction, and Yangsaeng of the Korean elderly living in the community. A quasi-experimental study design using a pretest-posttest control group was employed. Study participants were a total of 74 elderly (intervention: n = 37, control: n = 37) in Seoul, South Korea. Multicomponent Oriental Integrative Intervention was scheduled to hold two sessions a week, a total of sixteen sessions in 8 weeks, lasting 60 min per session. The measures were the general characteristics of the study participants, the Korean version of the Mini-Mental State Examination (MMSE-K), the Korean health status measure for the elderly, the Korean elderly life satisfaction scale, and the Yangsaeng measurement tool. Data were collected from March 2022 to May 2022. There were statistically significant differences in cognitive function, health status, life satisfaction, and Yangsaeng between the two groups. Multicomponent Oriental Integrative Intervention might be an effective intervention for improving the cognitive function, health status, life satisfaction, and Yangsaeng of the elderly living in the community. Health care providers need to pay attention to Multicomponent Oriental Integrative Intervention for the elderly living in the community.
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Vida Independente , Qualidade de Vida , Idoso , Cognição , Nível de Saúde , Humanos , Satisfação Pessoal , Qualidade de Vida/psicologia , Inquéritos e QuestionáriosRESUMO
Simulation studies involving mixture models inevitably aggregate parameter estimates and other output across numerous replications. A primary issue that arises in these methodological investigations is label switching. The current study compares several label switching corrections that are commonly used when dealing with mixture models. A growth mixture model is used in this simulation study, and the design crosses three manipulated variables-number of latent classes, latent class probabilities, and class separation, yielding a total of 18 conditions. Within each of these conditions, the accuracy of a priori identifiability constraints, a priori training of the algorithm, and four post hoc algorithms developed by Tueller et al.; Cho; Stephens; and Rodriguez and Walker are tested to determine their classification accuracy. Findings reveal that, of all a priori methods, training of the algorithm leads to the most accurate classification under all conditions. In a case where an a priori algorithm is not selected, Rodriguez and Walker's algorithm is an excellent choice if interested specifically in aggregating class output without consideration as to whether the classes are accurately ordered. Using any of the post hoc algorithms tested yields improvement over baseline accuracy and is most effective under two-class models when class separation is high. This study found that if the class constraint algorithm was used a priori, it should be combined with a post hoc algorithm for accurate classification.
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Concentrations of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), zinc (Zn), calcium (Ca), iron (Fe), nickel (Ni) and copper (Cu) were determined in 310 samples of commonly consumed spices from the market in Korea. The content of metals was assayed by acid wet digestion followed by inductively coupled plasma mass spectrometry (ICP-MS) or ICP. The content of Hg was analysed using a direct mercury analyser (DMA). Leafy spices had a significantly higher content of Pb, Cd, As, Hg, Ca and Ni when compared to those of fruit spices. Principal component analysis/cluster analysis (PCA/CA) analyses showed a high positive correlation and close proximities in the content of Pb and As in all samples, Zn and Ca in leafy spices and Cd and Zn in fruit spices.
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Metais Pesados , Cádmio/análise , Cobre , Contaminação de Alimentos/análise , Metais Pesados/análise , Análise Multivariada , República da Coreia , Especiarias/análiseRESUMO
Shiftwork nurses experience physical and psychological health problems related to shift work. This study aimed to examine the effects of Meridian acupressure on stress, fatigue, anxiety, and self-efficacy of shiftwork nurses in South Korea. A quasi-experimental pretest-posttest control group design was employed. Study participants were a total of 59 shiftwork nurses (intervention group: n = 29, control group: n = 30) in S hospital, Seoul, South Korea. The study was conducted at nurse stations in S hospital. Meridian acupressure as intervention was conducted for a total of 15 min on six Meridian acupressure points (GV 20, GB 12, GB 21, LI 11, SI 3, KI 1), 2 min 30 s (10 times for 15 s at a time) on each Meridian point. Measures were the stress scale, fatigue scale, State Anxiety Inventory, and self-efficacy scale, in Korean. Data were collected from July to August 2018. There were significant differences in the degrees of stress, fatigue, and anxiety of shiftwork nurses between the two groups. Meridian acupressure significantly decreased stress, fatigue, and anxiety of shiftwork nurses. This study provides preliminary evidence that Meridian acupressure was an effective intervention. Meridian acupressure could be applied to shiftwork nurses in various clinical situations.
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Acupressão , Meridianos , Ansiedade/terapia , Fadiga/terapia , Humanos , República da Coreia , Autoeficácia , SeulRESUMO
The number of older adults admitted to nursing homes is steadily increasing, and the health management for them is a very important issue in Korean society. This study aimed to examine the effects of Yangsaeng (health management) therapy on physical health status, depression, life satisfaction, and Yangsaeng (health management) of Korean older adults in nursing homes. A quasi-experimental study design using a pretest-posttest control group was employed. Study participants were a total of 80 older adults (intervention: n = 40, control: n = 40) in a nursing home in Seoul, South Korea. Yangsaeng therapy as an intervention consisted of the Meridian therapy and Qi-gong therapy. Yangsaeng therapy was conducted for 50 min per one time, twice a week, and for 10 weeks. Measures were general characteristics of study participants, Cornell Medical Index, Geriatric Depression Scale, life satisfaction scale, and Yangsaeng scale. Data were collected from April 2018 to March 2019. There were statistically significant differences on physical health status, depression, life satisfaction, and Yangsaeng between the two groups. Yangsaeng therapy was an effective intervention for improving physical health status, life satisfaction, and Yangsaeng, and for decreasing depression of older adults in nursing homes. Health care providers need to pay attention to Yangsaeng therapy as a Korean traditional intervention method for the health management of the older adults residing in nursing homes.
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Gerenciamento Clínico , Nível de Saúde , Casas de Saúde , Idoso , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , República da Coreia , Seul , Instituições de Cuidados Especializados de EnfermagemRESUMO
We report thin-film transistors (TFTs) with floating metal using a back-channel-etched (BCE) process. Since the BCE process reduces the active mask step compared to other processes, it has attracted attention as a back-plane process that could be used for mass production. To realize the long channel in the BCE process, a floating metal is required; this acts as a bridge in the middle of the channel. We used TCAD (Technology computer-aided design) simulations (Atlas 3D) to predict the characteristics of a-Si TFTs with various active layer thicknesses and numbers of floating metal components; simulation results were compared with real measurements. We explain why TFTs do not scale ideally when floating metals are used; this is related to the resistance and thickness of the active channel. If a thick and highly resistive active channel is used, a larger number of floating metals will require greater correction for ideal scaling. Additionally, considering the capacitance between the source metal and channel, the channel influence under the floating metal should be about 89%. We also suggest a new SPICE (Simulation Program with Integrated Circuit Emphasis) model for TFTs with floating metal based on TCAD simulations.
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BACKGROUND: Rapid and accurate cardiopulmonary resuscitation (CPR) performed by clinical nurses plays an important role in increasing the survival rate of cardiac arrest patients in the hospital. PURPOSE: This study examined the effects of a simulation-based CPR training program on knowledge, performance, and stress of CPR in clinical nurses. METHOD: A quasi-experimental pretest-posttest control group design was used. Study participants included 60 clinical nurses (experimental group, n = 30, and control group, n = 30) in a general hospital in Seoul, South Korea. A 4-hour simulation-based CPR training program was conducted. Measures included the knowledge scale and performance scale from the Korean Association of Cardiopulmonary Resuscitation and the Post Code Stress Scale in Korean. RESULTS: The simulation-based CPR training program significantly improved CPR knowledge (t = 4.664, p < .001) and performance (t = 4.940, p < .001), and decreased stress (t = -5.832, p < .001) in clinical nurses. CONCLUSION: These findings indicate a simulation-based CPR training program was effective in improving knowledge and performing CPR, as well as in decreasing stress of CPR in clinical nurses. [J Contin Educ Nurs. 2020;51(5):225-232.].
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Reanimação Cardiopulmonar , Enfermeiras e Enfermeiros , Treinamento por Simulação , Humanos , República da CoreiaRESUMO
AIM: Continuous program development and application are necessary in order to manage the health and address the problems of secondary metabolic disorders for people with intellectual disabilities. This study examines the effects of Tai Chi therapy on body mass index (BMI) and physical index among people with intellectual disabilities. METHODS: A quasi-experimental study using a pretest-post-test control group, non-synchronized design was employed. Samples were in total 104 people with intellectual disabilities (experimental: n = 67, control: n = 37) in two facilities in South Korea. They were randomly allocated using a coin toss into the two groups. Tai Chi therapy as an experimental intervention was the Sun style Tai Chi exercise, which consists of the warm-up (5 min), main exercise (45 min), and finishing (meditation, 10 min). Tai Chi therapy was conducted twice a week for a total of 40 sessions for 5 months (1 hour each) by one professional instructor. Measures were general characteristics of study participants, BMI as degree of obesity, and physical index. Data were analyzed using the SPSS 21.0 program (descriptive statistics, χ2 test, independent t test). A P value of less than .05 was considered statistically significant. RESULTS: There were statistically significant differences on fasting blood glucose (t = 4.351, P < .001) and high-density lipoprotein (t = -2.052, P = .043) in the physical index between the two groups. CONCLUSIONS: Tai Chi therapy was an effective intervention for decreasing fasting blood glucose and for increasing high-density lipoprotein in those with intellectual disabilities. Tai Chi therapy can be implied as a nursing intervention for intellectual disabilities in nursing practice.
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Índice de Massa Corporal , Deficiência Intelectual , Tai Chi Chuan , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Estudos Longitudinais , Masculino , Qualidade de Vida , República da CoreiaRESUMO
This paper provides results on a form of adaptive testing that is used frequently in intelligence testing. In these tests, items are presented in order of increasing difficulty. The presentation of items is adaptive in the sense that a session is discontinued once a test taker produces a certain number of incorrect responses in sequence, with subsequent (not observed) responses commonly scored as wrong. The Stanford-Binet Intelligence Scales (SB5; Riverside Publishing Company, 2003) and the Kaufman Assessment Battery for Children (KABC-II; Kaufman and Kaufman, 2004), the Kaufman Adolescent and Adult Intelligence Test (Kaufman and Kaufman 2014) and the Universal Nonverbal Intelligence Test (2nd ed.) (Bracken and McCallum 2015) are some of the many examples using this rule. He and Wolfe (Educ Psychol Meas 72(5):808-826, 2012. https://doi.org/10.1177/0013164412441937 ) compared different ability estimation methods in a simulation study for this discontinue rule adaptation of test length. However, there has been no study, to our knowledge, of the underlying distributional properties based on analytic arguments drawing on probability theory, of what these authors call stochastic censoring of responses. The study results obtained by He and Wolfe (Educ Psychol Meas 72(5):808-826, 2012. https://doi.org/10.1177/0013164412441937 ) agree with results presented by DeAyala et al. (J Educ Meas 38:213-234, 2001) as well as Rose et al. (Modeling non-ignorable missing data with item response theory (IRT; ETS RR-10-11), Educational Testing Service, Princeton, 2010) and Rose et al. (Psychometrika 82:795-819, 2017. https://doi.org/10.1007/s11336-016-9544-7 ) in that ability estimates are biased most when scoring the not observed responses as wrong. This scoring is used operationally, so more research is needed in order to improve practice in this field. The paper extends existing research on adaptivity by discontinue rules in intelligence tests in multiple ways: First, an analytical study of the distributional properties of discontinue rule scored items is presented. Second, a simulation is presented that includes additional scoring rules and uses ability estimators that may be suitable to reduce bias for discontinue rule scored intelligence tests.
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Psicometria/métodos , Simulação por Computador , Interpretação Estatística de Dados , Humanos , Inteligência , Testes de InteligênciaRESUMO
The interfaces between amorphous organic layers play an important role in the efficiency and lifetime of organic light emitting diodes (OLEDs). However, an atomistic understanding of the interface morphology is still poor. In this study, we theoretically investigate the interfacial structure of amorphous organic films using molecular dynamics simulations that mimic vapor-deposition processes. We find that molecularly sharp interfaces are formed by the vapor-deposition process as the interface thickness spans only a mono- or double-layer in terms of lie-down geometry. Interestingly, the interface is more diffusive into the upper layer due to asymmetric interdiffusion during the vapor-deposition process, which is well described by a simple random-walk model. Additionally, we investigate the change in the molecular orientation of interdiffused molecules, which is crucial for device performance.
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Levels of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) were evaluated in 359 samples of commonly consumed spices (cinnamon, parsley, basil, oregano, coriander seed, nutmeg, cumin, bay leaf, fenugreek, rosemary, thyme, fennel, sage, clove, marjoram, tarragon, caraway, dill seed, pepper, and turmeric) from the market in the Republic of Korea. The content of Pb, Cd, and As was assessed by acid wet digestion using a microwave oven and inductively coupled plasma mass spectrometry (ICP-MS). The content of Hg was analysed using a direct mercury analyzer (DMA). Pb, Cd, As, and Hg mean content in spices ranged from 0.039-0.972 mg kg-1, 0.013-0.315 mg kg-1, 0.121-0.861 mg kg-1, and 0.001-0.025 mg kg-1, respectively.
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Contaminação de Alimentos/análise , Metais Pesados/análise , Especiarias/análise , Arsênio/análise , Cádmio/análise , Lamiaceae/química , Chumbo/análise , Espectrometria de Massas/métodos , Mercúrio/análise , República da CoreiaRESUMO
Angelica gigas (AG) is effective against various medical conditions such as bacterial infection, inflammation, and cancer. It contains a number of coumarin compounds and the group of interest is the pyranocoumarin, which comprises decursin and decursinol angelate. This group has an effect on controlling inflammation, which is caused by excessive nitric oxide (NO) production. Heme oxygenases (HOs), particularly HO-1, play a role in regulating the production of NO. Thus, this study aimed to investigate the anti-inflammatory effects of AG by measuring HO-1 expression. Treatments with CH2Cl2 layer and Angelica gigas extract (AGE) showed the highest NO inhibition effects. Decursin, decursinol angelate, and nodakenin were isolated from the CH2Cl2 layer of AGE. Decursin also demonstrated the highest anti-oxidative effect among the coumarins. Although decursin had the best NO inhibition and anti-oxidative effects, the effects of AGE treatment far surpassed that of decursin. This is owing to the combination effect of the coumarins present within AGE, which is a solvent extract of AG. The expression of HO-1 is an effective indicator of the anti-inflammatory effects of AG. Based on the results of the coumarin compounds, HO-1 expression was found to be dose dependent and specific to decursin.
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Angelica/química , Anti-Inflamatórios/farmacologia , Regulação da Expressão Gênica , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Extratos Vegetais/farmacologia , Animais , Antioxidantes/farmacologia , Benzopiranos/farmacologia , Butiratos/farmacologia , Cumarínicos/farmacologia , Relação Dose-Resposta a Droga , Glucosídeos/farmacologia , Heme Oxigenase-1/genética , Proteínas de Membrana/genética , Camundongos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Óxido Nítrico/metabolismo , Células RAW 264.7RESUMO
An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%-20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks.
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Surtos de Doenças , Virus da Influenza A Subtipo H5N1/classificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Vírus Reordenados , Animais , Patos/virologia , Feminino , Genótipo , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/transmissão , Masculino , Mortalidade , República da Coreia/epidemiologia , Replicação ViralRESUMO
A 52-year-old man was presented with a huge left testicular mass and palpable cervical lymphadenopathy with retroperitoneal lymph node enlargement on an abdominal computed tomography. A left radical orchiectomy and an ultrasound-guided neck node biopsy were performed. A pathological examination revealed spermatocytic seminoma with extensive rhabdomyosarcomatous transformation, a condition known to be highly resistant to platinum-based chemotherapy. The patient received four cycles of etoposide, ifosfamide and cisplatin (VIP) chemotherapy. A repeat computed tomography revealed a substantial regression consistent with a partial response. Retroperitoneal lymph node dissection was attempted, which revealed rhabdomyosarcoma; however, complete microscopic resection was not achieved. After surgery, the residual abdominal lymph node progressed and salvage paclitaxel, ifosfamide and cisplatin (TIP) chemotherapy was employed, which again achieved a partial response. Here, we present a first case report of a spermatocytic seminoma with extensive rhabdomyosarcomatous transformation and multiple metastatic lymphadenopathies that showed a favorable response to platinum-based systemic chemotherapy.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Etoposídeo/uso terapêutico , Ifosfamida/uso terapêutico , Seminoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Cisplatino/administração & dosagem , Etoposídeo/administração & dosagem , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-IdadeRESUMO
DNA methylation and histone acetylation contribute to the transcriptional regulation of genes involved in apoptosis. We have demonstrated that docosahexaenoic acid (DHA, 22:6 n-3) and butyrate enhance colonocyte apoptosis. To determine if DHA and/or butyrate elevate apoptosis through epigenetic mechanisms thereby restoring the transcription of apoptosis-related genes, we examined global methylation; gene-specific promoter methylation of 24 apoptosis-related genes; transcription levels of Cideb, Dapk1, and Tnfrsf25; and global histone acetylation in the HCT-116 colon cancer cell line. Cells were treated with combinations of (50 µM) DHA or linoleic acid (18:2 n-6), (5 mM) butyrate or an inhibitor of DNA methyltransferases, and 5-aza-2'-deoxycytidine (5-Aza-dC, 2 µM). Among highly methylated genes, the combination of DHA and butyrate significantly reduced methylation of the proapoptotic Bcl2l11, Cideb, Dapk1, Ltbr, and Tnfrsf25 genes compared to untreated control cells. DHA treatment reduced the methylation of Cideb, Dapk1, and Tnfrsf25. These data suggest that the induction of apoptosis by DHA and butyrate is mediated, in part, through changes in the methylation state of apoptosis-related genes.
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Apoptose/efeitos dos fármacos , Butiratos/farmacologia , Neoplasias do Colo/metabolismo , Metilação de DNA/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Regiões Promotoras Genéticas/genética , Acetilação/efeitos dos fármacos , Antimetabólitos Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/genética , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Metilases de Modificação do DNA/antagonistas & inibidores , Proteínas Quinases Associadas com Morte Celular/genética , Decitabina , Células HCT116 , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Ácido Linoleico/farmacologia , Receptor beta de Linfotoxina/genética , Proteínas de Membrana/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Transcrição Gênica/efeitos dos fármacosRESUMO
The number of death due to cancer has been increasing in Korea. Chemotherapy is known to cause side effects because it damages not only cancerous cells but healthy cells. Recently, attention has focused on food-derived chemopreventive and anti-tumor agents or formulations with fewer side effects. Kimchi, most popular and widely consumed in Korea, contains high levels of lactic acid bacteria and has been shown to possess chemopreventive effects. This review focuses on Weissella cibaria and Lactobacillus plantarum, the representatives of kimchi lactic acid bacteria, in terms of their abilities to prevent cancer. Further studies are needed to understand the mechanisms by which lactic acid bacteria in kimchi prevent carcinogenic processes and improve immune functions.
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We have demonstrated that diets containing fish oil and pectin (FO/P) reduce colon tumor incidence relative to control (corn oil and cellulose [CO/C]) in part by inducing apoptosis of DNA-damaged colon cells. Relative to FO/P, CO/C promotes colonocyte expression of the antiapoptotic modulator, Bcl-2, and Bcl-2 promoter methylation is altered in colon cancer. To determine if FO/P, compared with CO/C, limits Bcl-2 expression by enhancing promoter methylation in colon tumors, we examined Bcl-2 promoter methylation, mRNA levels, colonocyte apoptosis and colon tumor incidence in azoxymethane (AOM)-injected rats. Rats were provided diets containing FO/P or CO/C, and were terminated 16 and 34 weeks after AOM injection. DNA isolated from paraformaldehyde-fixed colon tumors and uninvolved tissue was bisulfite modified and amplified by quantitative reverese transcriptase-polymerase chain reaction to assess DNA methylation in Bcl-2 cytosine-guanosine islands. FO/P increased Bcl-2 promoter methylation (P = 0.009) in tumor tissues and colonocyte apoptosis (P = 0.020) relative to CO/C. An inverse correlation between Bcl-2 DNA methylation and Bcl-2 mRNA levels was observed in the tumors. We conclude that dietary FO/P promotes apoptosis in part by enhancing Bcl-2 promoter methylation. These Bcl-2 promoter methylation responses, measured in vivo, contribute to our understanding of the mechanisms involved in chemoprevention of colon cancer by diets containing FO/P.
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Compostos Azo/toxicidade , Neoplasias do Colo , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Dieta , Óleos de Peixe/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Experimentais , Pectinas/farmacologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Animais , Apoptose/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/prevenção & controle , Masculino , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/prevenção & controle , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Ratos , Ratos Sprague-DawleyRESUMO
We have demonstrated that fish oil- and pectin-containing (FO/P) diets protect against colon cancer compared with corn oil and cellulose (CO/C) by upregulating apoptosis and suppressing proliferation. To elucidate the mechanisms whereby FO/P diets induce apoptosis and suppress proliferation during the tumorigenic process, we analyzed the temporal gene expression profiles from exfoliated rat colonocytes. Rats consumed diets containing FO/P or CO/C and were injected with azoxymethane (AOM; 2 times, 15 mg/kg body weight, subcutaneously). Feces collected at initiation (24 h after AOM injection) and at aberrant crypt foci (ACF) (7 wk postinjection) and tumor (28 wk postinjection) stages of colon cancer were used for poly (A)+ RNA extraction. Gene expression signatures were determined using Codelink arrays. Changes in phenotypes (ACF, apoptosis, proliferation, and tumor incidence) were measured to establish the regulatory controls contributing to the chemoprotective effects of FO/P. At initiation, FO/P downregulated the expression of 3 genes involved with cell adhesion and enhanced apoptosis compared with CO/C. At the ACF stage, the expression of genes involved in cell cycle regulation was modulated by FO/P and the zone of proliferation was reduced in FO/P rats compared with CO/C rats. FO/P also increased apoptosis and the expression of genes that promote apoptosis at the tumor endpoint compared with CO/C. We conclude that the effects of chemotherapeutic diets on epithelial cell gene expression can be monitored noninvasively throughout the tumorigenic process and that a FO/P diet is chemoprotective in part due to its ability to affect expression of genes involved in apoptosis and cell cycle regulation throughout all stages of tumorigenesis.