Accumulating evidence has confirmed the links between transfer RNA (tRNA) modifications and tumor progression. The present study is the first to explore the role of tRNA methyltransferase 5 (TRMT5), which catalyzes the m1G37 modification of mitochondrial tRNAs in hepatocellular carcinoma (HCC) progression. Here, based on bioinformatics and clinical analyses, we identified that TRMT5 expression was upregulated in HCC, which correlated with poor prognosis. Silencing TRMT5 attenuated HCC proliferation and metastasis both in vivo and in vitro, which may be partially explained by declined extracellular acidification rate (ECAR) and oxygen consumption rate (OCR). Mechanistically, we discovered that knockdown of TRMT5 inactivated the hypoxia-inducible factor-1 (HIF-1) signaling pathway by preventing HIF-1α stability through the enhancement of cellular oxygen content. Moreover, our data indicated that inhibition of TRMT5 sensitized HCC to doxorubicin by adjusting HIF-‍1α. In conclusion, our study revealed that targeting TRMT5 could inhibit HCC progression and increase the susceptibility of tumor cells to chemotherapy drugs. Thus, TRMT5 might be a carcinogenesis candidate gene that could serve as a potential target for HCC therapy.
Humans ; Carcinoma, Hepatocellular/pathology* ; Cell Hypoxia ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Liver Neoplasms/pathology* ; Signal Transduction/genetics* ; tRNA Methyltransferases/metabolism*

SIRT6 belongs to the conserved NAD⁺-dependent deacetylase superfamily and mediates multiple biological and pathological processes. Targeting SIRT6 by allosteric modulators represents a novel direction for therapeutics, which can overcome the selectivity problem caused by the structural similarity of orthosteric sites among deacetylases. Here, developing a reversed allosteric strategy AlloReverse, we identified a cryptic allosteric site, Pocket Z, which was only induced by the bi-directional allosteric signal triggered upon orthosteric binding of NAD⁺. Based on Pocket Z, we discovered an SIRT6 allosteric inhibitor named JYQ-42. JYQ-42 selectively targets SIRT6 among other histone deacetylases and effectively inhibits SIRT6 deacetylation, with an IC₅₀ of 2.33 μmol/L. JYQ-42 significantly suppresses SIRT6-mediated cancer cell migration and pro-inflammatory cytokine production. JYQ-42, to our knowledge, is the most potent and selective allosteric SIRT6 inhibitor. This study provides a novel strategy for allosteric drug design and will help in the challenging development of therapeutic agents that can selectively bind SIRT6.

Objective:To describe the experience of nurses in general hospital operating room for specialist management.Methods:A questionnaire survey was conducted among 226 operating room nurses using the questionnaire of specialist nurses' work obstruction factors. Eighteen of the operating room nurses were interviewed by phenomenological research methods in qualitative research.Results:The obstacles to the professional management of nurses in the operating room were mainly reflected in the difficulty of doing only the work of specialist nurses (96.46%,218/226), "there is no clear role positioning (93.81%, 212/226)", and "responsible for the work of several departments(89.82%, 203/226)." The refinement and analysis of the interview data showed that the management of specialist equipment could not be arranged and managed in a coordinated manner; the surgeons were over-reliant on the specialist nurses; the problem of setting up the positions of the senior nurses was outstanding; the nurses who were not the specialists have insufficient competence. With the sense of belonging; specialist nurses would have a slack situation.Conclusions:There are still many problems in the implementation of specialist management in the operating room of general hospitals. It is suggested that the rotation training of the operating room nurses should be carried out from the fixed professional group, the standardized training and the establishment of the mobile nurse database should be set up to promote the smooth implementation of the specialist management of the nurses in the operating room of the general hospital.

Currently there is no successful platform technology for the sustained release of protein drugs. It seems inevitable to specifically develop new materials for such purpose, and hence the understanding of protein-material interactions is highly desirable. In this study, we synthesized cholesterol-grafted polyglutamate (PGA--Chol) as a hydrophobically-modified polypeptide, and thoroughly characterized its interaction with a model protein (human serum albumin) in the aqueous solution by using circular dichroism, fluorescence methods, and light scattering. With the protein concentration fixed at 5 μmol/L, adding PGA--Chol polymers into the solution resulted in continuous blue shift of the protein fluorescence (from 339 to 332 nm), until the polymer molar concentration reached the same value as the protein. In contrast, the un-modified polyglutamate polymers apparently neither affected the protein microenvironment nor formed aggregates. Based on the experimental data, we proposed a physical picture for such protein-polymer systems, where the polymer first bind with the protein in a 1:1 molar ratio a fraction of their hydrophobic pendant cholesterol resides along the polymer chain. In this protein/polymer complex, there are excess unbound cholesterol residues. As the polymer concentration increases, the polymers form multi-polymer aggregates around 200 nm in diameter the same hydrophobic cholesterol residues. The protein/polymer complex also participate in the aggregation their excess cholesterol residues, and consequently the proteins are encapsulated into the nanoparticles. The encapsulation was also found to increase the thermal stability of the model protein.

Objective To prepare,characterize glycyrrhetinic acid lysinate,and study the solubilization and inhibitory action antitumor activity of glycyrrhetinic acid lysinate on cell proliferation of colorectal cancer cell line HCT-8. Methods Glycyrrhetinic acid lysinate was prepared by co-grinding glycyrrhetinic acid with lysine in 1∶1 molar mixture for 10 hours. Characterization of glycyrrhetinic acid lysinate was achieved by X-ray powder diffraction, infrared spectroscopy, and ultraviolet spectrum techniques.HPLC method was used to study the solubilization of glycyrrhetinic acid lysinate.The MTT method was used to assay the inhibitory action of glycyrrhetinic acid lysinate on cell proliferation. Results The solubility of glycyrrhetinic acid lysinate was enhanced 260 folds,compared with glycyrrhetinicacid in water. The inhibitory cell proliferation action on HCT-8 of glycyrrhetinic acid lysinate was 7 times higher than that of glycyrrhetinic acid. Conclusion The satisfactory water solubility and antitumor activity of glycyrrhetinic acid lysinate will be potentially useful for its application as a new pharmaceutical formulation in cancer treatment in the future.

Objective To study the distribution of surfactant protein A2 (SP-A2) haplotype and its association with preterm respiratory distress syndrome (RDS) susceptibility in a local Chinese cohort.Methods Using population base and case-control study cohorts,genotyping for four single nucleotide polymorphism (SNP) was performed,rs1059046,rs17886395,rs1965707,rs1965708,in 80 term infants,50 preterm infants with RDS (RDS group) and 50 preterm infants without RDS(control group) by using TaqMan (R) real-time polymerase chain reaction.Infants in RDS group and control group were matched according to gender and gestational age.Frequency of each haplotype was compared between preterm infants with RDS and without RDS,term infants and preterm infants without RDS.Results Most common haplotypes in term infants were 1A0,1A5,1A1.In each preterm infants groups with RDS and without RDS,1A0,1 A5,1 A1 were also the most common haplotypes.Among these three common haplotypes,frequency of 1A0 was lower in preterm infants,including RDS group and control group,than that in term infants.No significant difference was found between preterm groups with RDS and without RDS (P ＞ 0.05),neither in preterm infants with gestational age ≥32 or ＜ 32 weeks.Haplotype 1A0 frequency(0.542) in term infants was significantly higher than that in preterm infants ＜ 32 weeks without RDS (0.329) (x2 =6.06,P =0.01).Conclusions SP-A2 haplotype distribution in a local Chinese population shows ethnic characteristics to some extent.Only SP-A2 does not contribute to the susceptibility for preterm RDS.

OBJECTIVETo investigate the disease-causing mutation in a Chinese family affected with Usher syndrome type II.

METHODSAll of the 11 members from the family underwent comprehensive ophthalmologic examination and hearing test, and their genomic DNA were isolated from venous leukocytes. PCR and direct sequencing of USH2A gene were performed for the proband. Wild type and mutant type minigene vectors containing exon 42, intron 42 and exon 43 of the USH2A gene were constructed and transfected into Hela cells by lipofectamine reagent. Reverse transcription (RT)-PCR was carried out to verify the splicing of the minigenes.

RESULTSPedigree analysis and clinical diagnosis indicated that the patients have suffered from autosomal recessive Usher syndrome type II. DNA sequencing has detected a homozygous c.8559-2A>G mutation of the USH2A gene in the proband, which has co-segregated with the disease in the family. The mutation has affected a conserved splice site in intron 42, which has led to inactivation of the splice site. Minigene experiment has confirmed the retaining of intron 42 in mature mRNA.

CONCLUSIONThe c.8559-2A>G mutation in the USH2A gene probably underlies the Usher syndrome type II in this family. The splice site mutation has resulted in abnormal splicing of USH2A pre-mRNA.

Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Child ; China ; Extracellular Matrix Proteins ; genetics ; metabolism ; Female ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Pedigree ; Usher Syndromes ; genetics ; metabolism ; Young Adult

Qi She Pill (QSP) is a traditional Chinese medicine (TCM) prescription that has been used in treating cervical spondylosis radiculopathy for many years. In this study, a simple and sensitive method using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) on a reverse-phase C18 column was developed for the simultaneous determination of the 19 major components in QSP. We found that the optimum mobile phase for gradient elution was 0.1% formic acid and methanol. The correlation coefficients of all calibration curves were greater than 0.99. Recoveries measured at three concentration levels varied from 95.43% to 102.35%. Relative standard deviations of intra- and inter-day precisions were less than 4.45%. After successfully validating our method, we then applied it to the quantification of 19 components in QSP products to show that this method provides a new standard in quality assessment of TCM prescriptions containing multiple bioactive components.

Aged ; Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Humans ; Male

[Abst ract] Objective To explore the relationship between expression of S100B in hippocampus of depression model rats induced by chronic stress and its depression like behavior,and the antidepressant effect of fluoxetine.Methods 40 rats were put into control group,fluoxetine group,CUS group and CUS plus fluoxetine group,using random number table.Rats in each groups received corresponding treatment.Chronic unpredictable stresses (CUS) were performed on rats for 42 days.Fluoxetine (5 mg/(kg · d)) were delivered to rats by intragastric administration from day 22 to day 42.Then,S100B protein were marked and observed by immunohistochemical method.Open-field test,sucrose consumption and body weight were used to evaluate behavioral changes.Results Scores in behavioral test were reduced significantly by 42 days of stress (main effects of stress,P＜0.05).Effects of stress on behavioral scores were reversed by 21 days fluoxetine treatment (interactions,P＜0.05).CUS resulted in elevated expression of S100B in CA1,CA3 and DG sub-regions in experimental rats (OD values,CUS,0.331 ±0.01,0.353 ± 0.01,0.381 ± 0.007 ; control,0.238 ± 0.007,0.237 ± 0.010,0.228 ± 0.006.Simple effects of stress,P=0.000; P=0.000; P=0.000).Fluoxetine treatment reversed the elevated expression of S100B in CA1,CA3 and DG sub-regions in model rats (OD values:CUS plus fluoxetine,0.233 ± 0.015,0.240 ± 0.005,0.254± 0.015; fluoxetine,0.241±0.007,0.233±0.013,0.227±0.017; Interactions between fluoxetine and CUS,P=0.000; P=0.000; P=0.000).Conclusion Sub-regional over expression of S 100B in hippocampus is associated with depression like behavior of rats.Reversed S100B expression in these sub-regions is an indicator of effective antidepressant treatment but not a mechanism for it.