METTL3 Promotes OSCC Progression by Down-Regulating WEE1 in a m6A-YTHDF2-Dependent Manner.

Oral squamous cell carcinoma (OSCC) is a common and highly lethal epithelial cancer. This study aimed to confirm the role of METTL3 in promoting OSCC and investigate its specific underlying mechanisms. Expression of the METTL3, YTH domain-containing family 2 (YTHDF2), and WEE1 were examined in normal oral epithelial cells and OSCC cells. Cell functions were examined after overexpressing WEE1 in OSCC cells. MeRIP-qPCR analysis was used to detect WEE1 m6A levels in HOK, SCC25, and CAL27 cells. WEE1 and its m6A levels were evaluated in OSCC cells by knocking down METTL3/YTHDF2, assessing the interaction between METTL3/YTHDF2 and WEE1. The impact of METTL3 and YTHDF2 downregulation on WEE1 mRNA stability was also investigated. The tumor weight and volume in a nude mouse model of OSCC after overexpression of WEE1 and YTHDF2 were measured. Expression of Ki-67 and WEE1 in OSCC tissue was detected using immunohistochemistry. Compared to normal oral epithelial cells, METTL3 and YTHDF2 were upregulated in OSCC cells, while WEE1 was downregulated, and there was a negative correlation between WEE1 and METTL3/YTHDF2 expression. WEE1 overexpression inhibited proliferation, invasion, and migration while promoting apoptosis in OSCC cells. METTL3 and YTHDF2 bound to WEE1 mRNA. METTL3/YTHDF2 knockdown increased WEE1 levels and WEE1 mRNA stability. METTL3 inhibition reduced WEE1 m6A levels. Inhibition of METTL3 weakened the interaction between YTHDF2 and WEE1 mRNA. In vivo, overexpression of WEE1 suppressed OSCC development, which was reversed by overexpression of YTHDF2. METTL3 facilitates the progression of OSCC through m6A-YTHDF2-dependent downregulation of WEE1.

Sleep Deprivation and Heart Rate Variability in Healthy Volunteers: Effects of REM and SWS Sleep Deprivation.

Objective: Using PSG-guided acute selective REM/SWS sleep deprivation in volunteers, this study examined the effects of sleep deprivation on the cardiovascular and autonomic nervous systems, as well as the relationship between cardiac neuromodulation homeostasis and cardiovascular disease. Methods: An experiment was conducted using 30 healthy volunteers (male : female = 1 : 1, aged 26.33 ± 4.5 years) divided into groups for sleep deprivation of SWS and REM sleep, and then, each group was crossed over for normal sleep (2 days) and repeated sleep deprivation (1 day, 3 times). During the study period, PSG and ELECTRO ECG monitoring were conducted, and five-minute frequency domain parameters and blood pressure values were measured before and after sleep deprivation. Results: Changes in VLF, LFnu, LF/HF, HF, and HFnu after SWS sleep deprivation were statistically significant (P < 0.05), but not LF (P = 0.063). Changes in VLF, LF, HF, LF/HF, LFnu, and HFnu after REM sleep deprivation were not statistically significant (P > 0.05). Conclusions: An increase in sympathetic nerve activity results from sleep deprivation and sudden awakening from SWS sleep is associated with a greater risk of cardiovascular disease.

Adult intracranial infection caused by an extended-spectrum-beta-lactamase-producing strain of hypervirulent Klebsiella pneumoniae: a case report.

Background: Klebsiella pneumoniae is a conditional pathogen related to several infectious diseases. Few studies reported Klebsiella pneumoniae meningitis in the Chinese population, guidelines on diagnosis and treatment of Klebsiella pneumoniae meningitis should be considered due to its high lethality. Here, we report a case of adult intracranial infection caused by extended-spectrum-beta-lactamase (ESBL)-producing hypervirulent Klebsiella pneumoniae (hvKP) in a 65-year-old female, providing new insight for clinical awareness and epidemiological surveillance for ESBL-producing hvKP infection. Case Description: A 65-year-old female who had a recurrent fever for more than 1 month, and vomiting for 1 week was admitted to our hospital. The computed tomography (CT) results and laboratory results indicated systematic infection, and the blood culture confirmed the infection of Klebsiella pneumoniae. A combination of antibiotics including vancomycin, caspofungin, dexamethasone, and posaconazole oral suspension was given to the patient. Further, she exhibited a convulsion with unconsciousness, the CT revealed lacunar infarction and encephalomalacia. The following physical examination showed slight neck resistance, a weak light response of the eye, low muscle tension, suspicious left Babinski sign (+), and right Babinski sign (-). The CT and cerebrospinal fluid (CSF) analyses confirmed the diagnosis of intracranial infection caused by Klebsiella pneumoniae. We employed CSF microbial metagenomic next-generation sequencing (mNGS) was employed and the results suggested the high sequence of Klebsiella pneumoniae with drug-resistant gene SHV-type beta-lactamases (blaSHV). Subsequently, 2 g meropenem every 8 hours (q8h) prolonged for 3 hours was applied to treat intracranial infection, and her body temperature and infectious manifestations were gradually relieved. The CT results represented that pulmonary edema and pleural effusion were gradually dissipated and absorbed. Based on the improvement of clinical manifestations, the patient was discharged from the hospital and a close follow-up was conducted. Conclusions: An ESBL-producing strain of hvKP could lead to invasive infection such as severe intracranial infection, with a relatively favorable prognosis. The outcome of the disease caused by Klebsiella pneumoniae infection is firmly related to the phenotypic features, for instance, virulence factors and antibiotic susceptibility. Due to its high lethality, timely empiric anti-infection therapy and close surveillance are necessary for patients with Klebsiella pneumoniae infection in the clinic.

Effect of selective sleep deprivation on heart rate variability in post-90s healthy volunteers.

The 5-minute frequency domain method was used to examine the effects of polysomnography (PSG)-guided acute selective sleep deprivation (REM/SWS) on the cardiovascular autonomic nervous system, heart rate, and rhythm in healthy volunteers to understand the relationship between cardiac neuro regulatory homeostasis and cardiovascular system diseases in healthy subjects. The study included 30 healthy volunteers selected through the randomized-controlled method, randomly divided into REM sleep deprivation and SWS sleep deprivation groups. PSG analyses and dynamic electrocardiogram monitoring were done at night, during slow wave sleep or REM sleep. An all-night sleep paradigm, without any interruptions, was tested 3 times for comparison. The frequency domain parameter method was further used to monitor the volunteers 5 min before and after a period of sleep deprivation. According to the characteristics of the all-night sleep scatter plot, healthy volunteers were divided into abnormal and normal scatter plot groups. When compared with the period before sleep deprivation, high frequency (HF) and normalized high-frequency component (HFnu) were found to be decreased. Normalized low-frequency component (LFnu) increased in the abnormal scatter plot group after sleep deprivation, and this difference was statistically significant (P < 0.05). The scatter plot also showed that very low frequency (VLF) increased only in the normal group after deprivation and this difference, as well, was statistically significant (P < 0.05). The increase in diastolic blood pressure in the abnormal group was statistically significant (P < 0.05), but the change in blood pressure in the normal group was not statistically significant (P > 0.05). There are 62.5% of the patients and 20% of the employees that were observed to have abnormal whole-night sleep patterns during the uninterrupted whole-night sleep regime. Patients with atrial or ventricular premature beats (more than 0.1%), and those with ST-t changes during sleep, were all ascertained as abnormal. We concluded that some healthy people could face unstable autonomic nervous functioning related to their long-term tension, anxiety, time urgency, hostility, and other chronic stress states. In the face of acute sleep deprivation selectivity, mild stress based excitability of the vagus nerve is reduced, which diminishes the protective function, making them susceptible to conditions such as premature ventricular arrhythmia.

Network-based analysis of software change propagation.

The object-oriented software systems frequently evolve to meet new change requirements. Understanding the characteristics of changes aids testers and system designers to improve the quality of softwares. Identifying important modules becomes a key issue in the process of evolution. In this context, a novel network-based approach is proposed to comprehensively investigate change distributions and the correlation between centrality measures and the scope of change propagation. First, software dependency networks are constructed at class level. And then, the number of times of cochanges among classes is minded from software repositories. According to the dependency relationships and the number of times of cochanges among classes, the scope of change propagation is calculated. Using Spearman rank correlation analyzes the correlation between centrality measures and the scope of change propagation. Three case studies on java open source software projects Findbugs, Hibernate, and Spring are conducted to research the characteristics of change propagation. Experimental results show that (i) change distribution is very uneven; (ii) PageRank, Degree, and CIRank are significantly correlated to the scope of change propagation. Particularly, CIRank shows higher correlation coefficient, which suggests it can be a more useful indicator for measuring the scope of change propagation of classes in object-oriented software system.

Distal-less homeobox 2 promotes the osteogenic differentiation potential of stem cells from apical papilla.

Dental tissue-derived mesenchymal stem cells (MSCs) are a reliable cell source for dental tissue regeneration. However, the molecular mechanisms underlying the directed differentiation of MSCs remain unclear; thus, their use is limited. The histone demethylase, lysine (K)-specific demethylase 4B (KDM4B), plays critical roles in the osteogenic commitment of MSCs by up-regulating distal-less homeobox 2 (DLX2) expression. The DLX2 gene is highly expressed in dental tissue-derived MSCs but the roles of DLX2 in osteogenesis are unclear. Here, we investigate DLX2 function in stem cells from apical papilla (SCAPs). We found that, in vitro, DLX2 expression was up-regulated in SCAPs by adding BMP4 and by inducing osteogenesis. The knock-down of DLX2 in SCAPs decreased alkaline phosphatase (ALP) activity and mineralization. DLX2 depletion affected the mRNA expression of ALP, bone sialoprotein (BSP) and osteocalcin (OCN) and inhibited SCAP osteogenic differentiation in vitro. Over-expression of DLX2 enhanced ALP activity, mineralization and the expression of ALP, BSP and OCN in vitro. In addition, transplant experiments in nude mice confirmed that SCAP osteogenesis was triggered when DLX2 was activated. Furthermore, DLX2 expression led to the expression of the key transcription factor, osterix (OSX) but not to the expression of runt-related transcription factor 2 (RUNX2). Taken together, these results indicate that DLX2 is stimulated by BMP signaling and enhances SCAP osteogenic differentiation by up-regulating OSX. Thus, the activation of DLX2 signaling might improve tissue regeneration mediated by MSCs of dental origin. These results provide insight into the mechanism underlying the directed differentiation of MSCs of dental origin.