Association between LEPR Genotype and Gut Microbiome in Healthy Non-Obese Korean Adults.

The LEPR (leptin receptor) genotype is associated with obesity. Gut microbiome composition differs between obese and non-obese adults. However, the impact of LEPR genotype on gut microbiome composition in humans has not yet been studied. In this study, the association between LEPR single nucleotide polymorphism (rs1173100, rs1137101, and rs790419) and the gut microbiome composition in 65 non-obese Korean adults was investigated. Leptin, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were also measured in all participants. Mean ± SD (standard deviation) of age, body mass index, and leptin hormone levels of participants was 35.2 ± 8.1 years, 21.4 ± 1.8 kg/m2, and 7989.1 ± 6687.4 pg/mL, respectively. Gut microbiome analysis was performed at the phylum level by 16S rRNA sequencing. Among the 11 phyla detected, only one showed significantly different relative abundances between LEPR genotypes. The relative abundance of Candidatus Saccharibacteria was higher in the G/A genotype group than in the G/G genotype group for the rs1137101 single nucleotide polymorphism (p=0.0322). Participant characteristics, including body mass index, leptin levels, and other lipid levels, were similar between the rs1137101 G/G and G/A genotypes. In addition, the relative abundances of Fusobacteria and Tenericutes showed significant positive relationship with plasma leptin concentrations (p=0.0036 and p=0.0000, respectively). In conclusion, LEPR genotype and gut microbiome may be associated even in normal-weight Korean adults. However, further studies with a greater number of obese adults are needed to confirm whether LEPR genotype is related to gut microbiome composition.

Effect of Job Stress on Burnout among Nurses Responding to COVID-19: The Mediating Effect of Resilience.

Background: This study was conducted to evaluate the relationship of job stress, burnout, and resilience of 271 nurses who worked alternately at a university hospital in South Korea Province and a state-designated inpatient ward for COVID-19 in Korea. Methods: The study sample included nurses who worked at a university hospital in South Korea, during the period between February 2020 and May 2021. The participants (n = 271) responded to an online survey between April 2021 and 12 May 2021. The questionnaire included information related to job stress, burn out, and resilience. Results: In phase 1 of regression, job stress had a significant negative effect on resilience of recovery (ß = −0.397, p < 0.001). In phase 2, job stress had a significant positive effect on burnout (ß = 0.513, p < 0.001). In phase 3, resilience had a significant negative effect on burnout (ß = −0.459, p < 0.001). Seventy-five percent of burnout was directly associated with job stress, while 25% of burnout was indirectly associated through mediated effects, through resilience. Conclusions: The promotion of resilience would not only serve as the basis for active coping in situations where burnout and stress are severe, but also serve as a basic driving force for actively overcoming them. Further study to cope with stress and reduce burnout at the organizational level should be conducted.

Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines: less involvement of metallothionein.

BACKGROUND: Heptaplatin is a new platinum derivative with anticancer activity against various cancer cell lines, including cisplatin-resistant cancer cell lines (Cancer Chemother Pharmacol 1995; 35: 441). METHODS: Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines has been investigated in connection with metallothionein (MT). Cytotoxicity was determined by an MTT assay. MT mRNA, was determined by RT-PCR assay. Transfection study was carried out to examine the function of MT. RESULTS: Of various gastric cancer cell lines, SNU-638 and SNU-601 showed the highest and lowest levels of MT mRNA, respectively, showing 80-fold difference. The IC50 values of SNU-638 to cisplatin, carboplatin and heptaplatin were 11.2-fold, 5.1-fold and 2.0-fold greater than those of SNU-601, respectively. Heptaplatin was more effective against cisplatin-resistant and MT-transfected gastric cancer sublines than cisplatin or carboplatin was. In addition, heptaplatin attenuated cadmium, but not zinc, induction of MT. CONCLUSION: These results indicate that molecular mechanisms of heptaplatin effective against cisplatin-resistant gastric cancer sublines is at least in part due to the less involvement of MT in heptaplatin resistance as well as its attenuation of MT induction.