The Effect of Social Isolation, Loneliness, and Physical Activity on Depressive Symptoms of Older Adults during COVID-19: A Moderated Mediation Analysis

Depressive symptoms have been commonly reported in older adults during the coronavirus disease (COVID-19) pandemic. Social isolation as a result of social distancing to prevent COVID-19 was reported to increase the level of depressive symptoms both directly and indirectly through the mediating effect of loneliness. Depressive symptoms in older adults can be regulated through health behaviors such as physical activity. Therefore, this study used a moderated mediation model to explain depressive symptoms. The English Longitudinal Study of Ageing COVID-19 wave 2 data were used. A total of 296 individuals were excluded due to missing values, leaving a final sample of 6499. Depressive symptoms, social isolation, loneliness, and physical activity were used in the moderated mediation analysis with various demographic and general health variables as covariates. Loneliness was found to significantly mediate the relationship between social isolation and depression. While moderate physical activity significantly moderated the effects of social isolation and loneliness on depressive symptoms, mild physical activity alone significantly moderated the effects of loneliness on depressive symptoms. This study revealed the impact of social isolation on depressive symptoms directly and indirectly mediated by loneliness, with a moderating effect of moderate and mild physical activity in the elderly during COVID-19 in a moderated mediation model.

The Relationship between Smartphone Use Motives, Social Capital, Digital Literacy, and Life Satisfaction in Elderly Koreans

Background

As the elderly population increases, interest in life satisfaction in old age is increasing. We aimed to verify the relationship between social capital, smartphone use motives, and digital literacy and life satisfaction in Koreans aged 50-69 yr.

Methods

The data of 7,521 late-middle-aged and older adults from the 2019 survey on smartphone overdependence conducted by the National Information Society Agency were analyzed by hierarchical multi-regression analysis.

Results

A hierarchical multiple regression analysis indicated that income(β=0.062) and educational background(β=0.054) were positively related to life satisfaction. Among the smartphone use motives, lifestyle motive(β=-0.069) was negatively related to life satisfaction. Digital literacy(β=0.145) and Social capital(β=0.425) were positively related to life satisfaction.

Conclusion

Digital literacy and social capital were positively associated with life satisfaction. In addition, this study considered the effects of lifestyle-based apps, while past studies only focused on communication- and leisure-based smartphone activities as factors influencing life satisfaction in adults in their 50s-60s. This study can provide a theoretical framework for therapeutic interventions to improve life satisfaction in the elderly.

The Association between Adverse Childhood and Adulthood Experiences, Social Isolation, Loneliness, and Depression among Young Adults in South Korea

This study examined the association between social isolation, loneliness, and depressive symptoms among young adults in South Korea after controlling for sociodemographic variables, adverse child and adult experiences, and perceived health status. The researcher analyzed the data of 2014 young adults aged 18-34 years from the Youth Social Economic Survey using hierarchical multiple regression analysis conducted with IBM SPSS Statistics 28.0. Among the sociodemographic variables, sex, education, and household income were significantly related to depressive symptoms. Females reported higher levels of depressive symptoms than males, and those attending college or having a college (or higher) degree reported lower levels of depressive symptoms than those with a high-school diploma or lower. Higher household income was associated with lower levels of depressive symptoms. Perceived health status was negatively associated with depressive symptoms, while adverse childhood and adulthood experiences, social isolation, and loneliness were positively associated with it. Among the major independent variables, loneliness was most strongly related to depressive symptoms, whereas social isolation had the weakest relevance to it. The prediction model proposed explained 32.7% of the variance in depressive symptoms and was considered good. Therefore, focusing on loneliness may be more important than focusing on social isolation to prevent and deal with depressive symptoms among young adults.

Moderating Effects of Emotional Recognition Competency in Rejective Parenting and Adolescent Depression and Aggression

Rejective parenting is a major antecedent of emotional instability and aggressive behavioral problems. Previous studies have reported that emotional problems, such as depression, anxiety, aggression, and conduct problems in children and adolescents, improve through interventions that enhance emotional recognition competency. In this study, we explored whether the emotional recognition ability levels of individual adolescents moderated the pathway of negative parenting on aggression mediated by depression The moderated mediating effect of emotional recognition competency was investigated through examining 2265 first-year high school students using the 2021 data from the Korean Children and Youth Panel Survey 2018. There was no significant moderating effect on the direct pathway from rejective parenting to aggression. The moderating effect of emotional recognition competency on the indirect pathway leading to aggression through depression in rejective parenting was significant. These results suggest that the ability to correctly understand signals related to the emotions of others can play an important role in reducing depression and aggressive behavior by reducing conflict with people around them and experiencing more support.

A Systematic Review of Location Data for Depression Prediction

Depression contributes to a wide range of maladjustment problems. With the development of technology, objective measurement for behavior and functional indicators of depression has become possible through the passive sensing technology of digital devices. Focusing on location data, we systematically reviewed the relationship between depression and location data. We searched Scopus, PubMed, and Web of Science databases by combining terms related to passive sensing and location data with depression. Thirty-one studies were included in this review. Location data demonstrated promising predictive power for depression. Studies examining the relationship between individual location data variables and depression, homestay, entropy, and the normalized entropy variable of entropy dimension showed the most consistent and significant correlations. Furthermore, variables of distance, irregularity, and location showed significant associations in some studies. However, semantic location showed inconsistent results. This suggests that the process of geographical movement is more related to mood changes than to semantic location. Future research must converge across studies on location-data measurement methods.

Impacts of Perceived Stress, Neglect, Victim and Respect for Human Rights on Depression of Adolescents

The purpose of this study was to identify the impacts of perceived stress, neglect, online and offline violence, and respect for human rights on depression. To fulfill the purpose of the study, the data of 6277 middle and high school students (M = 15.64, SD = 1.69) from the Survey on the Human Rights of Children and Youth (2018) were used. The main results of the hierarchical multiple regression analysis are as follows. First, gender and age had significant impacts on depression. Second, neglect, perceived stress, and online violence were positively related to depression, whereas offline violence showed no relationship with depression. Third, respect for human rights, which is the final stage of the hierarchical multiple regression analysis, was negatively associated with depression. This study contributed to the research by verifying that perceived respect for human rights is a protective factor against depression.

The Relationship Between Parental Neglect, School Adjustment, and Smartphone Dependence in Korean Adolescents: Verification Using Multivariate Latent Growth Modeling

The Social bonding theory assumes that social ties are closely associated with maladaptive behavior, and this theory may be applied to explain the smartphone dependence in adolescence. The purpose of this study was to verify how school adjustment mediated the relationship between the parental neglect and smartphone dependence. The data from Korean Children and Youth Panel Survey were utilized in this study. Participants were 2280 students in the 2nd year of middle school [male 1152, female 1128; 13.89 years (SD = 0.34)] who were followed up for four years. We conducted a Multivariate Latent Growth Modeling (LGM) to verify the relationships between variables. In addition, mediating effect was analyzed using the Bootstrapping Test. Findings indicated that parental neglect was negatively associated with school adjustment in the first wave, and school adjustment showed a greater decrease as parental neglect indicated a greater increase. In addition, school adjustment was negatively associated with smartphone dependence in the first wave, and smartphone dependence showed a greater decrease as school adjustment indicated a greater increase. Mediating effect indicated that parental neglect indirectly influences smartphone dependence fully mediating school adjustment. In conclusion, parental neglect indirectly influences smartphone dependence by interfering with school adjustment. In addition, reducing the negative effects of parental neglect on school adaptation may be an effective strategy to prevent smartphone dependence in adolescence.

The Mediating Effect of Physical Function Decline on the Association Between Social Activity and Cognitive Function in Middle and Older Korean Adults: Analyzing Ten Years of Data Through Multivariate Latent Growth Modeling

Purpose

This study aimed to examine the long-term association between social activity, physical function decline and cognitive function, as well as verify the long-term mediating effect of physical function decline on the relationship between social activity and cognitive function.

Methods

Data from the Korean Longitudinal Study of Aging (KLoSA) that was collected over 10 years was analyzed. The sample included 10,240 adults aged 45–93 years (Mean age = 61.66 [SD = 11.061]). Multivariate latent growth modeling (LGM) was applied to verify the long-term effect of social activity and physical function on cognitive function.

Results

The results revealed that social activity had a positive impact on cognitive function and negative impact on physical function decline after controlling for age and education level. Additionally, physical function decline negatively influenced cognitive function. Finally, social activity indirectly affected cognitive function through physical function decline.

Conclusion

The contribution of this study was to test the long-term effect social activity on physical and cognitive function.

Long-Term Effect of Adverse Childhood Experiences, School Disengagement, and Reasons for Leaving School on Delinquency in Adolescents Who Dropout

Purpose: The purpose of this study was to verify the long-term effect of adverse childhood experiences (ACEs), school disengagement, and the reasons for leaving school on adolescent delinquency while adjusting for sex.

Methods: Data were collected from 663 teenagers [male 368, female 295; mean age = 16.81 (SD = 1.10); age range = 13–19 years] through a Longitudinal Survey and Support Plan for Dropouts.

Results: Multivariate latent growth modeling (LGM) demonstrated that ACEs and school disengagement are positively associated with delinquency and the mediating effect of school disengagement on association between ACEs and delinquency was verified. Teenagers who quit school for personal reasons reported fewer instances of delinquent behavior than adolescents who left because of school reasons.

Conclusion: This study suggests that researchers and teachers need to consider ACEs and school disengagement as a warning index for delinquency with school dropout. In addition, the reason for leaving school should be considered to clarify the effect of school dropout on delinquency in adolescents who dropout.

ADHD, suicidal ideation, depression, anxiety, self-esteem, and alcohol problem in Korean juvenile delinquency

The purpose of this study is to evaluate the prevalence rates of externalizing symptom, ADHD, as well as internalizing symptoms, depression, anxiety, suicidal ideation, self-esteem, and alcohol problem in Korea juvenile delinquency for the first time in Korea. A case-control study design was used. It also examined the associations with ADHD, suicidal ideation, depression, anxiety, self-esteem, and alcohol problem between the Juvenile Delinquency group and the comparison group in Korea.A series of questionnaires were provided to a total of 251 participants (149 from the juvenile delinquency group and 102 from the comparison group) from October 2015 to December 2015 in Korea. All participants were evaluated using KARS, SSI, BDI, BAI, RSI, and CAGE. This study showed the relationship between ADHD, suicidal ideation, depression, anxiety, self-esteem, and alcohol problem in Korean juvenile delinquency. Also this study showed that ADHD and self-esteem were important factors in predicting juvenile delinquency. Therefore, in order to prevent juvenile delinquency, special attention, and consideration are needed for adolescents with high ADHD or low self-esteem.

The relationship between bicultural identity, acculturative stress, and psychological well-being in multicultural adolescents: Verification using multivariate latent growth modelling

This study aimed to examine causal relationships between bicultural identity, acculturative stress, and subjective well-being among multicultural adolescents. Secondary longitudinal data that were obtained from 1,635 multicultural adolescents were analysed. The results showed that bicultural identity had a positive effect on psychological well-being and a negative impact on acculturative stress; in addition, greater acculturative stress was associated with lower psychological well-being. Finally, bicultural identity indirectly affected psychological well-being by mediating the effects of acculturative stress. These findings underscore the need to facilitate the adaptation of multicultural adolescents by reducing acculturative stress and promoting bicultural acceptance in educational institutions.

The Relationships between Addiction to Highly Caffeinated Drinks, Burnout, and Attention-Deficit/ Hyperactivity Disorder

Objectives:

This study aimed to evaluate the addiction to highly caffeinated drinks among university students, and we investigated the relationships between smartphone addiction, depression, anxiety, attention-deficit/hyperactivity disorder (ADHD), burnout, self-esteem, impulsiveness in high caffeine drink addiction risk group (high caffeine group). We also compared these mental health factors differences between the high caffeine group and the control group; and, investigated the relative risk between the independent variables of the high caffeine group.

Methods:

This study was conducted in Korea, from June 2015 to July 2016. A set of questionnaires was administered on 511 college students.

Results:

The participants who belonged to the high caffeine group were more likely to demonstrate the symptoms of ADHD and higher levels of burnout and impulsiveness. Further, the results of logistic regression analysis confirmed the association between the high caffeine group and burnout.

Conclusion:

These behaviors among university students addicted to highly caffeinated drinks suggests the need for timely and effective interventions for those at risk of addiction.

Individual and social stress, social capital, and depressive symptoms as predictors of adolescent suicide in South Korea: A mediated moderation model

This study examined the interactive effects of strain induced by individual and social stress and social capital on suicide, highlighting depressive symptoms as mediator in these relationships. This study used data from 5000 adolescents aged 14-18 years. Strain due to individual stress was found to have a direct effect on suicide, but strain due to social stress did not have a direct effect on suicide. The interactive effect of strain and social capital significantly predicted depressive symptoms and suicide. In the relationship between strain and suicide, the interactive effect of strain and social capital was mediated by depressive symptoms.

The influence of emotional difficulty, parent-child relationship, peer relationships, materially-oriented and appearance-oriented attitudes on adolescent problem behavior

This study explored predictors of adolescent problem behavior utilizing panel data from the National Youth Policy Institute. Data were collected from June 2013 to August 2013 from 3195 middle school students living in 15 cities of South Korea. Data were analysed using hierarchical regression in two steps. The first step included gender and school record; the second step added emotional difficulty, parent-child relationship, peer relationships, self-esteem, materially oriented attitude, and appearance-oriented attitude. Results showed that male students had greater problem behaviors than female students. Greater emotional difficulties were associated with greater problem behaviors. On the other hand, a better parent-child relationship and better peer relationships were related to fewer problem behaviors. Notably, greater materially and appearance-oriented attitudes were related to greater problem behaviors. This study implies that excessively extrinsic values or attitudes should be discouraged to prevent teenager problem behavior.

The relationships between perceived parenting style, learning motivation, friendship satisfaction, and the addictive use of smartphones with elementary school students of South Korea: Using multivariate latent growth modeling

We examined how perceived parenting style, friendship satisfaction, and academic motivation influence the addictive use of smartphones longitudinally. We utilized the panel data (from 2010–2012) of Korean children and youth panel survey of the National Youth Policy Institute. Data were collected from 2,376 individuals in the first year (boys: 1,241, girls: 1,135), 2264 individuals in the second year (boys: 1,180, girls: 1,084), and 2,218 individuals in the third year (boys: 1,167, girls: 1,051). Results of the multivariate latent growth modeling indicated that higher democratic parenting (warmth, supervisory, and rational explanation) was related to lower addictive use of smartphones. And, the more perceived democratic parenting was high, the more academic motivation and friendship satisfaction were high. Also, friendship satisfaction and academic motivation negatively influenced the addictive use of smartphones; the more friendship satisfaction and academic motivation increased rapidly over time, the more the addictive use of smartphones decreased over time. These results imply that affective and supervisory parenting can positively impact peer relationship and learning motivation, and the satisfaction of peer relationship and academic motivation can be protective factors for the addictive use of smartphones.

Prediction by data mining, of suicide attempts in Korean adolescents: a national study

OBJECTIVE

This study aimed to develop a prediction model for suicide attempts in Korean adolescents.

METHODS

We conducted a decision tree analysis of 2,754 middle and high school students nationwide. We fixed suicide attempt as the dependent variable and eleven sociodemographic, intrapersonal, and extrapersonal variables as independent variables.

RESULTS

The rate of suicide attempts of the total sample was 9.5%, and severity of depression was the strongest variable to predict suicide attempt. The rates of suicide attempts in the depression and potential depression groups were 5.4 and 2.8 times higher than that of the non-depression group. In the depression group, the most powerful factor to predict a suicide attempt was delinquency, and the rate of suicide attempts in those in the depression group with higher delinquency was two times higher than in those in the depression group with lower delinquency. Of special note, the rate of suicide attempts in the depressed females with higher delinquency was the highest. Interestingly, in the potential depression group, the most impactful factor to predict a suicide attempt was intimacy with family, and the rate of suicide attempts of those in the potential depression group with lower intimacy with family was 2.4 times higher than that of those in the potential depression group with higher intimacy with family. And, among the potential depression group, middle school students with lower intimacy with family had a 2.5-times higher rate of suicide attempts than high school students with lower intimacy with family. Finally, in the non-depression group, stress level was the most powerful factor to predict a suicide attempt. Among the non-depression group, students who reported high levels of stress showed an 8.3-times higher rate of suicide attempts than students who reported average levels of stress.

DISCUSSION

Based on the results, we especially need to pay attention to depressed females with higher delinquency and those with potential depression with lower intimacy with family to prevent suicide attempts in teenagers.

The mediating effects of attribution styles on the relationship between overt-covert narcissism and forgiveness

The aim in the current study was to investigate the causal relationships among the variables of covert-overt narcissism, causal attribution, responsibility attribution, and forgiveness based on the entailment model. Our aim was to differentiate between overt and covert narcissism in terms of their relationship with forgiveness. First, our findings in this study demonstrated that only covert narcissism was associated with forgiveness, whereas there was no association between overt narcissism and forgiveness. Second, path analysis revealed that both causal attribution and responsibility attribution mediated the relationship between covert narcissism and forgiveness, but this was not the case for overt narcissism. In addition, responsibility attributions mediated the relationship between causal attributions and forgiveness. Study implications are discussed.

Clarithromycin and amikacin vs. clarithromycin and moxifloxacin for the treatment of post-acupuncture cutaneous infections due to Mycobacterium abscessus: a prospective observational study

An outbreak of post-acupuncture cutaneous infections due to Mycobacterium abscessus occurred in Ansan, Korea, from November 2007 through to May 2008. During this time a prospective, observational, non-randomized study was conducted involving 52 patients that were diagnosed with cutaneous M. abscessus infection. We compared the clinical response between patients treated with clarithromycin plus amikacin regimen and those treated with clarithromycin plus moxifloxacin regimens with regard to time to resolution of the cutaneous lesions. Among the 52 study patients, 33 were treated with clarithromycin plus amikacin, and 19 were treated with clarithromycin plus moxifloxacin. The baseline characteristics for the treatment groups were not significantly different, except for initial surgical excision (n = 27 vs. 6, respectively, p = 0.001). The median time (weeks) to resolution of the lesions in the clarithromycin plus moxifloxacin-treated subjects was significantly shorter than that in the clarithromycin plus amikacin-treated subjects (17 ± 1.1 vs. 20 ± 0.9, respectively, p = 0.017). With adjustments for age, location of lesions, prior incision and drainage, and excision during medical therapy, clarithromycin plus moxifloxacin-treated subjects were more likely to have resolved lesions (hazard ratio, 0.387; 95% confidence interval, 0.165-0.907; p = 0.029). The frequency of drug-related adverse events in the two treatment groups was not significantly different (n = 18 vs. 14, respectively; p = 0.240). The most common adverse event was gastrointestinal discomfort. The results of our study showed that the combination regimen of clarithromycin and moxifloxacin resulted in a better clinical response than a regimen of clarithromycin plus amikacin when used for treatment of cutaneous M. abscessus infection.

Gene expression profiles in squamous cell cervical carcinoma using array-based comparative genomic hybridization analysis

Our aim was to identify novel genomic regions of interest and provide highly dynamic range information on correlation between squamous cell cervical carcinoma and its related gene expression patterns by a genome-wide array-based comparative genomic hybridization (array-CGH). We analyzed 15 cases of cervical cancer from KangNam St Mary's Hospital of the Catholic University of Korea. Microdissection assay was performed to obtain DNA samples from paraffin-embedded cervical tissues of cancer as well as of the adjacent normal tissues. The bacterial artificial chromosome (BAC) array used in this study consisted of 1440 human BACs and the space among the clones was 2.08 Mb. All the 15 cases of cervical cancer showed the differential changes of the cervical cancer-associated genetic alterations. The analysis limit of average gains and losses was 53%. A significant positive correlation was found in 8q24.3, 1p36.32, 3q27.1, 7p21.1, 11q13.1, and 3p14.2 changes through the cervical carcinogenesis. The regions of high level of gain were 1p36.33-1p36.32, 8q24.3, 16p13.3, 1p36.33, 3q27.1, and 7p21.1. And the regions of homozygous loss were 2q12.1, 22q11.21, 3p14.2, 6q24.3, 7p15.2, and 11q25. In the high level of gain regions, GSDMDC1, RECQL4, TP73, ABCF3, ALG3, HDAC9, ESRRA, and RPS6KA4 were significantly correlated with cervical cancer. The genes encoded by frequently lost clones were PTPRG, GRM7, ZDHHC3, EXOSC7, LRP1B, and NR3C2. Therefore, array-CGH analyses showed that specific genomic alterations were maintained in cervical cancer that were critical to the malignant phenotype and may give a chance to find out possible target genes present in the gained or lost clones.

Anatomical and radiological study of the superior and inferior gluteal arteries in the gluteus maximus muscle for musculocutaneous flap in Koreans

The position, distribution pattern, and perforating branch of the superior gluteal artery (SGA) and the inferior gluteal artery (IGA) in the gluteus maximus muscle (GMM) were investigated through fine dissection and the radiological method. The SGA was located at about the upper one-third of the posterior superior iliac spine (PSIS)-greater trochanter of the femur (GT) line and medially at about 1cm from the line. The IGA was located at around the middle point of the PSIS-ischial tuberosity (IT) line. The perforating branches passed through the muscle to the subcutaneous tissue and were distributed to the GMM that divided the upper and lower parts; the SGA supplied to the upper two-fifths of the GMM; and the IGA supplied to the rest of the muscle. The course of the SGA and the IGA in the GMM were classified into four types according to their distribution patterns, and the most common type was the typical type whereby the IGA supplied an area larger than the SGA. These results were somewhat different from previous studies, but these differences must be considered for a safe and effective flap procedure.

Development of anticancer gene vaccine interact with human papillomavirus oncoprotein inhibition

Adeno-associated virus (AAV) Rep 78 protein is known to inhibit the promoter site of several oncogenes and viral genes, including the human papillomavirus (HPV) type 16 E6 transforming genes. The biochemical studies of Rep 78 have been reported, but the effects of Rep 78 gene-mediated inhibition of HPV 16 E6 promoter activity on the various human cervical carcinoma cells have not been characterized. pEGFP-N1 vector, cloned by AAV-mediated Rep 78, is transfected into cervical carcinoma cells. Transfection efficiency of Rep 78 was approximately 30-60% different. Messenger RNA (mRNA) and protein expression of Rep 78 gene was significantly higher on day 1 of the transfection of Rep 78 DNA in CaSki cells, and DNA level of HPV 16 E6 was decreased on day 1 of the transfection. The growth of CaSki cervical cancer cells was only 10-15% inhibited by Rep 78, and the other cervical cells, HeLa, HeLaS3, HT3, and QGU, were unaffected by Rep 78 transfection. In spite of the high efficiency of Rep 78 gene transformation and expression rate, we could not show the significant growth inhibition in various cervical cancer cell lines. Taken together, long-term expression of Rep 78 strategy might be needed for cervical carcinoma gene therapy using AAV vector.

Cellular process classification of human papillomavirus-16-positive SiHa cervical carcinoma cell using Gene Ontology

This study utilized mRNA differential display and the Gene Ontology (GO) analysis to characterize the multiple interactions of a number of genes involved in human papillomavirus (HPV)-16-induced cervical carcinogenesis. We used HPV-16-positive cervical cancer cell line (SiHa) and normal human keratinocyte cell line (HaCaT) as a control. Each gene has several biological functions in the GO, and hence, we chosen the several functions for each gene. and then, the specific functions were correlated with gene expression patterns. The results showed that 157 genes were up- or down-regulated above two-fold and organized into mutually dependent subfunction sets depending on the cervical cancer pathway, suggesting the potentially significant genes of unknown function. The GO analysis suggested that cervical cancer cells underwent repression of cancer-specific cell-adhesive properties. Also, genes belonging to DNA metabolism such as DNA repair and replication were strongly down-regulated, whereas significant increases were shown in protein degradation and in protein synthesis. The GO analysis can overcome the complexity of the gene expression profile of the HPV-16-associated pathway and identify several cancer-specific cellular processes as well as genes of unknown function. Also, it can become a major competing platform for the genome-wide characterization of carcinogenesis.

Anti-cancer effect of adenovirus p53 on human cervical cancer cell growth in vitro and in vivo

To evaluate anti-tumor effects of recombinant adenovirus p53, time-course p53, E6 expression, and cell growth inhibition were investigated in vitro and in vivo using cervical cancer cell lines such as CaSki, SiHa, HeLa, HeLaS3, C33A, and HT3. The cell growth inhibition was studied via cell count assay, MTT assay and neutral red assay. After transfecting AdCMVp53 into SiHa cells-xenografted nude mice, the transduction efficiency and anti-tumor effect were investigated for a month. The results showed that adenoviral p53 expression induced significant growth suppression on the cancer cells, in which E6 transcript was strongly repressed, and that the expression of p53 and E6 were remarkably dependent on each cell type. The transduction efficiency was highly maintained in vivo as well as in vitro, and the size of tumor was remarkably decreased in comparison with AdCMVLacZ control. The results suggest that the adenovirus-mediated p53 gene transfection was done very effectively in vitro and in vivo experiment, and the cell growth was suppressed via p53-dependent apoptotic cell death, and that the anti-tumor effect could be related to E6 and p53 expression pattern.

Necrosis-like death with plasma membrane damage against cervical cancer cells by photodynamic therapy

In order to elucidate the antitumor effect of photodynamic therapy (PDT) using the photosensitizing agent hematoporphyrin derivative (Photogem) and a diode laser, we evaluated the cell death of uterine cancer cell lines (CaSki, HT3, HeLa, and SKOV-3) and mice transplanted with TC-1 lung cancer cells. Morphological changes, MTT assay, flow cytometry, cytotoxicity, and tumor growth-inhibition study were evaluated at various time intervals after PDT. The results showed that the survival rates of each cell line decreased with time and dose-response after performing PDT. Also, PDT-induced damage of cancer cells was almost entirely confined to necrosis of the tumor cells in the early time courses. The irradiation of CaSki cells in the presence of Photogem induced plasma membrane disruption and cell shrinkage, indicating the plasma membrane as the main target for Photogem. In the experiment in vivo, the time courses of Photogem with irradiation showed significantly longer survival and a significantly smaller tumor size compared to those in the untreated control groups, and resorption of the tumor after PDT treatment was observed. Collectively, our results indicated that Photogem possesses tumor-specific affinity, and necrosis-like death with plasma membrane damage was postulated to be the principal mechanism of the antitumor effect of PDT using Photogem.