A comparative study on eating habits and mental health of Korean middle school students according to their bedtime across regions: using data from the 2020-2022 Korea Youth Risk Behavior Survey.

BACKGROUND/OBJECTIVES: The objective of this study was to compare dietary habits and mental health among middle school students in urban and rural areas based on bedtime, and to provide evidence supporting appropriate bedtime for Korean middle school students in relation to their healthy dietary habits and mental well-being. SUBJECTS/METHODS: The study population consisted of 25,681 second-year middle school students who participated in the Korea Youth Risk Behavior Survey in 2020-2022. Participants were asked about their bedtime and wake-up time during the past 7 days and were classified into five categories. The study compared the general characteristics, academic factors, dietary habits, and mental health of urban and rural students based on their bedtime. RESULTS: Bedtime was found to be later in the following order: urban female students, rural female students, urban male students, and rural male students. As bedtime got later, the rates of smoking and alcohol consumption increased. Students who went to bed before 11 p.m. had lower academic performance, while rural male students who went to bed after 2 a.m. had lower academic performance. Later bedtime was associated with increased smartphone usage, skipping breakfast, consuming fast food, and drinking carbonated beverages. Later bedtime was also associated with higher perceived stress levels, particularly among students who went to bed after 2 a.m., higher rates of suicidal ideation, experiencing sadness and despair, as well as the prevalence of clinically significant anxiety disorders. CONCLUSION: These results suggest that middle school students who go to bed too late have higher rates of smoking and alcohol drinking, as well as unhealthy eating habits, stress, suicidal ideation, sadness, and anxiety. Therefore, it is necessary to provide educational and social institutional support to promote adequate sleep for the health of adolescents.

Phloretin Inhibits the Proliferation of Breast Cancer Cells Through the Down-regulation of Estrogen Receptor α.

BACKGROUND/AIM: Phloretin is a natural flavonoid compound found in some plants, such as apples and pears, as well as in the bark of apple trees. Phloretin has been shown to have inhibitory effects on glucose transporters in cells and can potentially inhibit the growth of cancer cells. However, the mechanism by which phloretin regulates the expression of estrogen receptor alpha (ERα), a key transcription factor in breast cancer, is still unclear. This study investigated how phloretin affects the growth of ERα positive human breast cancer cells. MATERIALS AND METHODS: The growth of breast cancer cell lines, including MCF7 and T47D, was examined using cell proliferation and colony formation assays. Western blotting and semi-quantitative RT-PCR were used to examine protein and mRNA levels, respectively. Localization of cellular proteins was analyzed using subcellular fractionation. Transient transfection and reported gene assays were used to elucidate the impact of phloretin on cell proliferation and ERα transactivation. RESULTS: Phloretin decreased ERα expression at the mRNA and protein levels in MCF7 and T47D cells. It also inhibited the binding of ERα to the estrogen response element present in the promoter of target genes. Moreover, treatment with phloretin inhibited the expression of cyclin D1 and breast cancer marker gene pS2, which are known ERα target genes. Consequently, it inhibited the growth of ERα-positive human breast cancer cells. Furthermore, inhibition of breast cancer growth by phloretin was found to be mediated through both the ERα and ERK1/ERK2 pathways. CONCLUSION: Phloretin, a dihydrochalcone extracted from natural sources, exhibits the ability to regulate ERα function and suppress breast cancer cell proliferation.

Interaction of genetic and environmental factors for body fat mass control: observational study for lifestyle modification and genotyping.

Previous studies suggested that genetic, environmental factors and their interactions could affect body fat mass (BFM). However, studies describing these effects were performed at a single time point in a population. In this study, we investigated the interaction between genetic and environmental factors in affecting BFM and implicate the healthcare utilization of lifestyle modifications from a personalized and genomic perspective. We examined how nutritional intake or physical activity changes in the individuals affect BFM concerning the genetic composition. We conducted an observational study including 259 adult participants with single nucleotide polymorphism (SNP) genotyping and longitudinal lifestyle monitoring, including food consumption and physical activities, by following lifestyle modification guidance. The participants' lifelog data on exercise and diet were collected through a wearable device for 3 months. Moreover, we measured anthropometric and serologic markers to monitor their potential changes through lifestyle modification. We examined the influence of genetic composition on body fat reduction induced by lifestyle changes using genetic risk scores (GRSs) of three phenotypes: GRS-carbohydrate (GRS-C), GRS-fat (GRS-F), and GRS-exercise (GRS-E). Our results showed that lifestyle modifications affected BFM more significantly in the high GRS class compared to the low GRS class, indicating the role of genetic factors affecting the efficiency of the lifestyle modification-induced BFM changes. Interestingly, the influence of exercise modification in the low GRS class with active lifestyle change was lower than that in the high GRS class with inactive lifestyle change (P = 0.022), suggesting the implication of genetic factors for efficient body fat control.

Antiangiogenic Therapy Impedes Infiltration by CD4+ and CD8+ Cells Into an Early Colon Tumor.

BACKGROUND: While the majority of angiogenesis studies have focused on the late stages of cancer, the emergence of neovascularization in colon tumorigenesis has been observed an earlier stage than expected. Recent reports implied that early angiogenesis might be a defense mechanism to stimulate the natural clearance of microadenomas during colon tumorigenesis. However, little is known about how early angiogenesis affects the natural clearance of tumors. METHODS: Spontaneous colon tumors were developed in adenomatous polyposis coli conditional knockout mice with Cre recombinase adenovirus administration. Vascular endothelial growth factor (VEGF) antagonist, DC101, was administrated to determine the effect of early angiogenesis and then infiltration of immune cells into tumor and concentration of cytokines were evaluated. RESULTS: The continuous administration of the VEGF receptor 2 antagonist DC101 in the mouse models impeded the infiltration by CD4+ and CD8+ cells into the tumor region. Furthermore, the administration of the VEGF antagonist decreased the amounts of anti-tumoral cytokines such as interleukin (IL)-6 and IL-10. CONCLUSIONS: We revealed that newly formed vessels during tumorigenesis can be channels for particular anti-tumoral immune cells. Our results may confer insight for the clinical development of an efficient antiangiogenic therapeutic manual and a timely chemoprevention to suppress tumor growth.

Synthesis of norlignans and in vitro inhibitory activity of antigen-induced degranulation.

The synthesis and biological evaluation of a series of novel norlignans are described. Norlignans were evaluated for their inhibitory activity on the release of ß-hexosaminidase, a marker of degranulation, from RBL-2H3 cells induced by the IgE-antigen complex. The results showed that norlignans 4c and 4e potently inhibited degranulation, with IC(50) values of 18.3 and 17.9 µM, respectively.

Self-assembly of Cationic, Hetero- or Homo-nuclear Ru(II) Macrocyclic Rectangles and their Photophysical, Electrochemical and Biological Studies.

A series of supramolecular rectangles, including two mixed-metal Ru/Pt complexes, have been formed by the coordination-driven self-assembly of a range of arene-Ru "molecular clip" acceptors (1a-1d) with rigid dipyridyl-based ligands (2a-2d) over the course of 10 hours in solution. The isolated products were characterized by multinuclear NMR ((1)H and (13)C or (31)P), HR-ESI-MS and an X-ray diffraction study to support the ascribed two-component rectangular structures. The rectangles were further characterized by UV-Vis and fluorescence studies. The redox behaviors of rectangles 3ca and 3da were also determined using cyclic voltammetry. Additionally, the antitumor activities of the suite of rectangles were determined against various human cancer cell lines and significant activity was shown by complexes 3ca, 3da, 3cb, 3cc and 3cd, with IC(50) values as low as 2.65 µM.

Coordination Driven Self-Assembly and Anticancer Activity of Molecular Rectangles Containing Octahedral Ruthenium Metal Centers.

The synthesis of new 2+2 metalla-rectangles via coordination driven self-assembly of octahedral Ru(II) based acceptors and amide donors is described. To evaluate their in vitro cytotoxic properties, preliminary biological assays were carried out for various human cancer cell lines, and our results show that the cytotoxicity level of 3 is comparable or even greater in the cases of SK-hep-1 and HCT-15 than that of the reference drug cisplatin.

Hexanuclear self-assembled arene-ruthenium nano-prismatic cages: potential anticancer agents.

Two novel nano-cage compounds, 8 and 9, were prepared by self-assembly of the ruthenium complexes 4 and 5, and the tripodal donor 1. The cytotoxicity of 8 was found to be considerably stronger than that of cisplatin. The complex 8 inhibited tumor cell proliferation by interfering into regulatory pathways of the cell cycle via apoptosis.

Dietary intake of nitrate relative to antioxidant vitamin in relation to breast cancer risk: a case-control study.

Nitrate is a precursor in the endogenous formation of N-nitroso compounds, which are potent animal carcinogens, whereas antioxidant vitamins have been suggested to protect against carcinogenesis. Interestingly, nitrate and antioxidant vitamins stem from the same dietary sources. We investigated whether the intake of nitrate relative to antioxidant vitamins is associated with the risk of breast cancer. A total of 362 breast cancer cases were matched to the 362 controls by age and menopausal status. Dietary intake was assessed using a quantitative food frequency questionnaire with 121 food items by trained interviewers. The nitrate to antioxidant vitamin consumption ratio was then calculated. Conditional logistic regression analysis was used to obtain odds ratios (ORs) and corresponding 95% confidence intervals (CI). Mean intakes of nitrate for cases and controls were 421 mg/day and 424 mg/day, respectively. Intakes of nitrate, nitrate/beta-carotene, nitrate/vitamin C, and nitrate/vitamin E were not associated with breast cancer risk. However, higher breast cancer risk was observed with higher intake of nitrate/folate (OR = 2.03, 95% CI = 1.16-3.54, P for trend = 0.052). Our results suggest that lowering the ratio of nitrate to folate intake may be effective in reducing breast cancer risk.

A case-control study on seaweed consumption and the risk of breast cancer.

Gim (Porphyra sp.) and miyeok (Undaria pinnatifida) are the seaweeds most consumed by Koreans. We investigated the association between the intake of gim and miyeok and the risk of breast cancer in a case-control study. Cases were 362 women aged 30-65 years old, who were histologically confirmed to have breast cancer. Controls visiting the same hospital were matched to cases according to their age (sd 2 years) and menopausal status. Food intake was estimated by the quantitative FFQ with 121 items, including gim and miyeok. Conditional logistic regression analysis was used to obtain the OR and corresponding 95 % CI. The average intake and consumption frequency of gim in cases were lower than in controls. The daily intake of gim was inversely associated with the risk of breast cancer (5th v. 1st quintile, OR, 0.48; 95 % CI, 0.27, 0.86; P for trend, 0.026) after adjustment for potential confounders. After stratification analysis was performed according to menopausal status, premenopausal women (5th v. 1st quintile, OR, 0.44; 95 % CI, 0.24, 0.80; P for trend, 0.007) and postmenopausal women (5th v. 1st quintile, OR, 0.32; 95 % CI, 0.13, 0.80; P for trend, 0.06) showed similar inverse associations between gim intake and the risk of breast cancer after an adjustment for potential confounders except dietary factors. Miyeok consumption did not have any significant associations with breast cancer. These results suggest that high intake of gim may decrease the risk of breast cancer.

Altered urinary profiles of polyamines and endogenous steroids in patients with benign cervical disease and cervical cancer.

The risk of cancer of the cervix is linked with sexual behavior. Although infectious agents, such as human papillomaviruses (HPVs) are implicated, these alone may be insufficient to induce the disease. We investigated the potential role of estrogen, androgen, and polyamine metabolism as co-factors in the development of cervical cancer. We obtained urine samples from patients with benign cervical disease (n=18) and cervical cancer (n=18) and from age-matched normal female subjects (n=25). For 11 polyamine determination, an improved and sensitive gas-chromatographic with nitrogen/phosphorus-detection (GC/NPD) procedure was used. The urinary levels of 25 androgens and corticoids and 16 estrogens were quantitatively determined by gas chromatography-mass spectrometry-selected ion-monitoring (GC/MS/SIM). In the patients with cervical cancer, the ratio of 16alpha-hydroxy estrone (16alpha-OH E1)/2-hydroxy estrone (2-OH E1), putrescine (Put)/N(1)-acetylspermidine (N(1)-acSpd) and 5beta-tetrahydrocortisol (THF)/5alpha-tetrahydrocortisol (5alpha-THF) were significantly increased in comparison to the values of the normal controls. These data suggest: (1) an increase of 16alpha-hydroxylation in estrogen metabolism; (2) the high activity of polyamine oxidase (PAO) in polyamine metabolism; and (3) the low activity of 5alpha-reductase in androgen metabolism may play a significant role in the development of cervical cancer. Although additional research is necessary, the combination of 16alpha-OH E1/2-OH E1 and THF/5alpha-THF may provide a dual marker for the discrimination of benign cervical disease and cervical cancer.