Association between smartphone overdependence and generalized anxiety disorder among Korean adolescents.

BACKGROUND: This study aimed to investigate the association between smartphone overdependence and generalized anxiety disorder among South Korean adolescents. METHODS: Participants were selected from the Korean Youth Health Behavior Survey 2020. The primary dependent variable was the generalized anxiety disorder that was measured based on seven item instrument (GAD-7). The main exposure of interest was the smartphone overdependence using the integrated scale developed by the National Information Society Agency in Korea. Weighted chi-square test and multiple logistic regression were used to assess the association between smartphone overdependence and generalized anxiety disorder. RESULTS: The final participants comprised of 54,948 middle and high school students. 13,775 students (25.1 %) were classified as the smartphone overdependence group. Of those who reported overly dependent on smartphones, 2803 students (20.3 %) had generalized anxiety disorder. The risk for generalized anxiety disorder were 2.15 folds (95 % CI 2.01-2.30) higher among the overdependence group in compared to their counterparts. Specifically, the risk for generalized anxiety disorder increased when smartphone has negatively affected relationships with friends and colleagues (OR: 2.35, 95 % CI 2.08-2.64). The sensitivity of smartphone overdependence scale was verified and the risk for generalized anxiety disorder increased in magnitude with the severity of smartphone overdependence. CONCLUSION: The findings of the study showed significant association between smartphone overdependence and generalized anxiety disorder among South Korean adolescents. The negative changes in social relationships due to excessive smartphone use and the severity of overdependence accounted for the risk for generalized anxiety disorder.

Association between Nighttime Work and HbA1c Levels in South Korea.

Background: As the world has become a 24 h society, people's demands have generated various work schedules, leading to an increase in workers' health problems. The study aimed to investigate the association between nighttime work and HbA1c levels among South Korean adults over the age of 30. Methods: Participants were selected from the 2016−2019 Korea National Health and Nutrition Survey; those diagnosed with diabetes were excluded. The dependent variable was the HbA1c level reported in the KNHANES health examination report. The main independent variable was the participant's work schedule. Work schedules were classified into three categories based on the participant's report: (1) day; (2) night and overnight, and (3) other. Generalized multiple linear regression was used, and the significance level was defined as p < 0.05. Results: The participants comprised 4773 men and 4818 women. Those engaged in the "day" schedule served as the reference group. Among the male participants, the "night and overnight" group had significantly larger HbA1c (%) levels than the "day" group (ß = 0.061, p = 0.0085). Among these nighttime male workers, HbA1c (%) levels were particularly higher in the people who were physically inactive (ß = 0.094, p = 0.0031), slept less than 7 h (ß = 0.108, p = 0.0009), and skipped meals (ß = 0.064, p = 0.0401). Conclusion: Our results revealed an association of nighttime work with increased HbA1c levels in male participants. High-risk groups for HbA1c levels require careful observation of physical activity, sleeping time, and eating habits.

rdxA, frxA, and efflux pump in metronidazole-resistant Helicobacter pylori: Their relation to clinical outcomes.

BACKGROUND AND AIM: rdxA and frxA mutations and enhancement of efflux pump have been suggested as the cause of metronidazole resistance in Helicobacter pylori. This study was performed to investigate the resistance mechanisms related to clinical eradication outcome, and to examine direct involvement of hefA in metronidazole-resistant isolates with intact rdxA and frxA. METHODS: A total of 53 H. pylori-positive patients who were treated with metronidazole-containing sequential or quadruple therapy from 2011 to 2015 were enrolled. The metronidazole susceptibility of H. pylori isolates was examined by agar dilution test. Mutations in rdxA and frxA, were analyzed with DNA sequencing, and impact of hefA on metronidazole resistance was examined with quantitative real-time reverse transcription polymerase chain reaction, knockout and genetic complementation test for hefA. RESULTS: Seven mutation types of rdxA and/or frxA were found in H. pylori isolated from non-eradicated subjects. rdxA mutation was associated with eradication failure (P = 0.002), and nonsense mutation in rdxA reduced eradication efficacy (P = 0.009). hefA expression was significantly higher in resistant isolates (P < 0.001), especially in rdxA(-)frxA(-) as compared to rdxA(+)frxA(+) (P = 0.027). Resistant isolates with no mutation in rdxA and frxA became susceptible after hefA knockout. Genetic complementation for hefA recovered metronidazole resistance in all of three hefA knockout mutants. CONCLUSIONS: These results suggest that rdxA mutations play a critical role in metronidazole resistance as well as the outcomes of eradication therapy. In addition, hefA seems to be directly involved in metronidazole resistance, which explains the resistance in clinical isolates with intact rdxA and frxA.

Association of polymorphisms in virulence factor of Helicobacter pylori and gastroduodenal diseases in South Korea.

BACKGROUND AND AIM: Clinical outcomes of Helicobacter pylori (HP) infection have been shown to be dependent on the variability of virulence factors. The aim of this study was to evaluate the prevalence of each virulence factor and the association between polymorphisms of the virulence factors of HP, and the clinical outcome of gastroduodenal diseases in South Korea. METHODS: Four hundred one HP colonies were analyzed (75 colonies from 45 controls; 71 colonies from 39 benign gastric ulcer [BGU] patients; 102 colonies from 54 duodenal ulcer [DU] patients; 121 colonies from 77 stomach cancer patients; and 32 colonies from 25 dysplasia patients). Polymerase chain reaction amplifications for vacA, cagA, iceA, oipA, and dupA were performed using DNA extract from HP isolates cultured from mucosal biopsy specimens. dupA was regarded as positive when all of jph0718, jph0719, and dupA were positive. RESULTS: Most colonies were composed of vacA s1 (100.0%), i1 (100.0%) and m1 (92.9%), cagA-positive (87.2%), iceA1 (95.8%), oipA-positive (91.2%), and dupA-negative (52.0%) genotypes. dupA was more frequently expressed in BGU (81.3%), DU (74.7%), and dysplasia (41.7%) than control (16.7%) (P < 0.001). Infection by dupA-positive HP showed an increased risk of BGU (odds ratio 33.06, 95% confidence interval 11.91-91.79) and DU (odds ratio 15.60, 95% confidence interval 6.49-37.49). CONCLUSION: HP infection in South Koreans appears to be closely related to highly virulent strains (vacA s1/i1/m1, cagA(+), iceA1(+), and oipA(+)), except dupA. dupA has an intimate association with the development of peptic ulcer diseases.

Fumigant antifungal activity of essential oil components from Acorus gramineus against three phytopathogenic fungi.

Analysis by gas chromatography-mass spectrometry led to the identification of 26 compounds in Acorus gramineus essential oil. The antifungal activity of the identified compounds was tested singularly by using standard compounds. Allyl isothiocyanate and cis-asarone showed inhibition rates of 100% against P. cactorum at 28 mg/l air. In a test with C. parasitica and E. circinatum, allyl isothiocyante and cis-asarone showed moderate activity at 28 mg/l air.

Toxicity of plant essential oils and their components against Lycoriella ingenua (Diptera: Sciaridae).

Plant essential oils from 20 plant species were tested for their insecticidal activity against larvae of Lycoriella ingenua (Dufour) (Diptera: Sciaridae) by using a fumigation bioassay. Good insecticidal activity (>90%) against larvae of L. ingenua was achieved with essential oils of caraway seed Carum carvi (L.)], lemongrass [Cymbopogon citratus (D.C.) Stapf.], mandarine (Citrus reticulate Blanco), nutmeg (Myristica fragrans Houtt), cade (Juniperus oxycedrus L.), spearmint (Mentha spicata L.), cumin (Cuminum cyminum L.), and thyme red [Thymus vulgaris (L.)] oils at 30 X 10-3 mg/1 air. Among them, caraway seed, spearmint, cumin, and thyme red essential oils were highly effective against L. ingenua at 20 x 10(-3) mg/ml air. Analysis by gas chromatography-mass spectrometry led to identification of 4, 9, 8, and 17 compounds from caraway seed, spearmint, cumin, and thyme red oils, respectively. These compounds were tested individually for their insecticidal activities against larvae of L. ingenua, and compared with the toxicity of dichlorvos. Carvacrol, thymol, linalool, cuminaldehyde, p-cymen, terpinen-4-ol, and carvone was effective at 10 x 10(-3) mg/l. The insecticidal activity of dichlorvos was 60% at 10 x 10(-3) mg/ml. Effects of four selected plant essential oils on growth of oyster mushroom, Pleurotus ostreatus, also were investigated.

Fumigant activity of plant essential oils and components from Schizonepeta tenuifolia against Lycoriella ingenua (Diptera: Sciaridae).

Plant essential oils from 21 plant species were tested for their insecticidal activities against larvae of Lycoriella ingenua Dufour (Diptera: Sciaridae) by using a fumigation bioassay. Good insecticidal activity against larvae of L. ingenua was achieved with essential oils of Acorus gramineus Solander, Schizonepeta tenuifolia Briquet, and Zanthoxylum piperitum De Candolle at 25 microg/ml air. S. tenuifolia oil showed the most potent insecticidal activity among the plant essential oils. At 12.5 microg/ml air concentration, S. tenuifolia oil caused 96.6% mortality, but mortality decreased to 60% at 3.125 microg/ml air. Analysis by gas chromatography-mass spectrometry led to identification of three major compounds from S. tenuifolia oil. These three compounds were tested individually for their insecticidal activities against larvae of L. ingenua and compared with the toxicity of dichlorvos. Pulegone was the most toxic, followed by menthone and limonene with LC50 values of 1.21, 6.03, and 15.42 microg/ml, respectively. LC50 of dichlorvos was 8.13 microg/ml. Effects of S. tenuifolia and its components on growth of Pleurotus ostreatus (Jacq. ex Fr.) Kummer also were investigated.