BACKGROUNDMitochondrial DNA (mtDNA) is the only hereditary substance besides nucleus, which is composed of a code region and a non-code D-loop region. The aim of this study is to investigate the hypervariable region II (HVRII) mutation of mtDNA in peripheral blood leucocyte, pericancerous tissues and cancer tissues of lung squamous cell carcinoma patients, and to explore its significance.

METHODSWhite blood cells, pericancerous tissues and cancer tissues were obtained from 15 cases of lung squamous cell carcinoma patients and mtDNA were extracted by one step method. HVRII fragments were amplified by PCR. Mutations were determined by DNA sequencing and the mutations of HVRII were analysed.

RESULTSIn 15 lung squamous cell carcinoma patients, 14 patients showed mutation in HVRII(93.33%), 88 mutations were found totally. Eighty-seven mutations located in H-strand origin region, especially in the conserved sequence blocks and the mtTF1, 2 binding site (TFX and TFY).

CONCLUSIONSThe results suggest that the mutation frequency of HVRII in cancer tissues of lung squamous cell carcinoma patients is very high and it might play an important role in carcinogenesis of the lung.

Objective To analyze the relationship between the expression of hsa_circ_401724 and the in-flammatory response in type 2 diabetes mellitus(T2DM)patients and pancreatic islet cell function.Methods A total of 102 patients with T2DM treated in Linfen Central Hospital from April 2017 to December 2022 were selected as the observation group,and 100 healthy subjects with normal glucose tolerance were se-lected as the control group during the same period.The levels of tumor necrosis factor α(TNF-α),interleukin-6(IL-6)and intercellular adhesion molecule-1(ICAM-1)in the blood of the subjects were detected by en-zyme-linked immunosorbent assay to evaluate the levels of inflammatory factors in the subjects.The relative expression level of hsa_circ_401724/U6 was calculated according to the dissolution curve,and the pancreatic islet cell function of the subjects was assessed,including homeostasis model assessment of insulin resistance(HOMA-IR)and homeostatic model assessment beta cell function(HOMA-β)as assessed by homeostasis model.Pearson correlation was used to analyze the correlation between hsa_circ_401724 expression level and inflammation and pancreatic islet cell function,and Logistics regression model was used to analyze the rela-tionship between hsa_circ_401724 expression level and inflammation and pancreatic islet cell function.Results The levels of HOMA-IR,TNF-α,IL-6 and ICAM-1 in observation group were significantly higher than those in control group,while the levels of HOMA-β in observation group were significantly lower than those in control group,with statistical significance(P＜0.05).The relative expression level of hsa_circ_401724 in observation group(0.75±0.13)was significantly higher than that in control group(0.24±0.06),and the difference was statistically significant(P＜0.05).The levels of HOMA-IR,TNF-α,IL-6 and ICAM-1 in hsa_circ_401724 high expression group were significantly higher than those in hsa_circ_401724 low expres-sion group,and the levels of HOMA-β were significantly lower than those in hsa_circ_401724 low expression group.The difference was statistically significant(P＜0.05).The relative expression level of hsa_circ_401724 was positively correlated with the levels of HOMA-IR,TNF-α,IL-6 and ICAM-1(r=0.657,0.671,0.703,0.698,P＜0.05).hsa_circ_401724 expression level was negatively correlated with HOMA-β level(r=-0.611,P＜0.05).The high expression of hsa_circ_401724 was an independent risk factor affecting the levels of HOMA-IR,HOMA-β,TNF-α,IL-6 and ICAM-1 in T2DM patients(P＜0.05).Conclusion The high ex-pression of hsa_circ_401724 is related to the inflammatory response and the decline of pancreatic islet cell function in T2DM patients.

Background The mental health status of prison officers is crucial to the efficiency, security, and stability of a prison, and it is essential to pay attention to the factors that influence their mental health. Objective To understand the mental health status of prison officers, and analyze how nature exposure affects their mental health problems and a potential mediating role of mental fatigue. Methods A cross-sectional survey was carried out from May to June 2022 among 1392 prison officers from eight prisons in a province, and a total of 1284 valid questionnaires were recovered. The Nature Exposure Scale, Mental Fatigue Scale, and Depression-Anxiety-Stress Scale were used to assess nature exposure, mental fatigue, and mental health indicators among prison officers, and to explore the effect of nature exposure on mental health problems and a potential mediating role of mental fatigue. Results The recruited prison officers showed high levels of depression, anxiety, and stress. The prevalence rates of depression, anxiety, and stress were 59.11% (759/1284), 60.67% (779/1284),and 43.93% (564/1284), respectively. The results of correlation analysis revealed that nature exposure was negatively related with mental fatigue and mental health indicators (depression, anxiety, and stress) (r_s=−0.242, −0.308, −0.235, −0.254, P<0.01), while mental fatigue was positively correlated with mental health indicators (depression, anxiety, and stress) (r_s=0.546, 0.533, 0.536, P<0.01). The PROCESS macro results showed that the level of nature exposure among prison officers negatively associated with depression, anxiety, and stress (β=−0.180, −0.104, −0.123), and mental fatigue played a mediating role, with indirect effects of −0.200, −0.192, and −0.199, respectively. Conclusion The levels of depression, anxiety, and stress of prison officers are higher than those of other occupations. Nature exposure negatively associates with depression, anxiety, and stress, that is, it may directly alleviate the mental health problems of prison officers; and it may also alleviate mental health problems by relieving mental fatigue.

Gap junctions mediate direct communication between cells; however, toxicological cascade triggered by nonessential metals can abrogate cellular signaling mediated by gap junctions. Although cadmium (Cd) is known to induce apoptosis in organs and tissues, the mechanisms that underlie gap junction activity in Cd-induced apoptosis in BRL 3A rat liver cells has yet to be established. In this study, we showed that Cd treatment decreased the cell index (a measure of cellular electrical impedance) in BRL 3A cells. Mechanistically, we found that Cd exposure decreased expression of connexin 43 (Cx43), increased expression of p-Cx43 and elevated intracellular free Ca2+ concentration, corresponding to a decrease in gap junctional intercellular communication. Gap junction blockage pretreatment with 18β-glycyrrhizic acid (GA) promoted Cd-induced apoptosis, involving changes in expression of Bax, Bcl-2, caspase-3 and the mitochondrial transmembrane electrical potential (Δψm). Additionally, GA was found to enhance ERK and p38 activation during Cd-induced activation of mitogen-activated protein kinases, but had no significant effect on JNK activation. Our results indicated the apoptosis-related proteins and the ERK and p38 signaling pathways may participate in gap junction blockage promoting Cd-induced apoptosis in BRL 3A cells.
Animals ; Apoptosis/*drug effects ; Cadmium/*toxicity ; Calcium/metabolism ; Cell Communication/drug effects ; Connexin 43/genetics ; Enzyme Activation/drug effects ; Gap Junctions/*drug effects ; Gene Expression Regulation/drug effects ; Hepatocytes/cytology/*drug effects ; Rats ; Signal Transduction/drug effects