An Mtr4/ZFC3H1 complex facilitates turnover of unstable nuclear RNAs to prevent their cytoplasmic transport and global translational repression.

Many long noncoding RNAs (lncRNAs) are unstable and rapidly degraded in the nucleus by the nuclear exosome. An exosome adaptor complex called NEXT (nuclear exosome targeting) functions to facilitate turnover of some of these lncRNAs. Here we show that knockdown of one NEXT subunit, Mtr4, but neither of the other two subunits, resulted in accumulation of two types of lncRNAs: prematurely terminated RNAs (ptRNAs) and upstream antisense RNAs (uaRNAs). This suggested a NEXT-independent Mtr4 function, and, consistent with this, we isolated a distinct complex containing Mtr4 and the zinc finger protein ZFC3H1. Strikingly, knockdown of either protein not only increased pt/uaRNA levels but also led to their accumulation in the cytoplasm. Furthermore, all pt/uaRNAs examined associated with active ribosomes, but, paradoxically, this correlated with a global reduction in heavy polysomes and overall repression of translation. Our findings highlight a critical role for Mtr4/ZFC3H1 in nuclear surveillance of naturally unstable lncRNAs to prevent their accumulation, transport to the cytoplasm, and resultant disruption of protein synthesis.

Parathyroid hormone receptor-1 signaling aggravates hepatic fibrosis through upregulating cAMP response element-binding protein-like 2.

BACKGROUND AND AIMS: Parathyroid hormone receptor-1 (PTH1R) is a class B G protein-coupled receptor central to skeletal development, bone turnover, and calcium homeostasis. However, the role of PTH1R signaling in liver fibrosis is largely unknown. Here, the role of PTH1R signaling in the activation of HSCs and hepatic fibrosis was examined. APPROACH AND RESULTS: PTH1R was highly expressed in activated HSCs and fibrotic liver by using human liver specimens or carbon tetrachloride (CCl 4 )-treated or methionine and choline-deficient diet (MCD)-fed C57/BL6 mice. The mRNA level of hepatic PTH1R was positively correlated to α-smooth muscle actin in patients with liver cirrhosis. Mice with HSCs-specific PTH1R deletion were protected from CCl 4 , MCD, or western diet, plus low-dose CCl 4 -induced liver fibrosis. Conversely, parathyroid hormone (PTH) aggravated liver fibrosis in CCl 4 -treated mice. Mouse primary HSCs and LX2 cell lines were used for in vitro experiments. Molecular analyses by luciferase reporter assays and chromatin immunoprecipitation assays in combination with mRNA sequencing in HSCs revealed that cAMP response element-binding protein-like 2 (Crebl2), a novel regulator in HSCs treated by PTH that interacted with mothers against decapentaplegic homolog 3 (SMAD3) and increased the transcription of TGFß in activating HSCs and collagen deposition. In agreement, HSCs-specific Crebl2 deletion ameliorated PTH-induced liver fibrosis in CCl 4 -treated mice. CONCLUSIONS: In both mouse and human models, we found that PTH1R was highly expressed in activated HSCs and fibrotic liver. PTH1R signaling regulated collagen production in the HSCs through Crebl2/SMAD3/TGFß regulatory circuits. Blockade of PTH1R signaling in HSCs might help mitigate the development of liver fibrosis.

Analytical and clinical performance evaluation of a new NT-proBNP assay.

BACKGROUND: The study evaluated the performance of the Mindray N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a healthy population in China, focusing on creating a reference range for future clinical applications adjusted according to different demographics. METHODS: The study measured NT-proBNP in 2277 healthy individuals. We analyzed age and sex-stratified data, performed precision, accuracy, linearitcvy, and detection limit studies, and evaluated method comparison and consistency between Roche and Mindray assays on 724 serum samples. We used Excel 2010, Medcalc, and GraphPad Prism 9. RESULTS: In males, the 97.5th centile NT-proBNP concentration at age < 45, 45 to 54, 55 to 64, 65 to 74 and ≧ 75 were 89.4 ng/L, 126 ng/L, 206 ng/L, 386 ng/L and 522 ng/L, respectively. In females, the concentration of NT-proBNP at the same age was 132 ng/L, 229 ng/L, 262 ng/L, 297 ng/L and 807 ng/L, respectively. The repeatability precision coefficient of variation (CV%) for NT-proBNP was between 0.86 and 1.65 in analytical performance. In contrast, the reproducibility precision (CV%) for NT-proBNP was between 1.52 and 3.22, respectively. The study found a bias of accuracy of 3.73% in low-value samples (concentration: 148.69) and 7.31% in high-value samples (concentration: 1939.08). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 125 ng/L were 96.6%, 92.3%, 84.2%, and 98.5%, respectively. In contrast, those of 300 ng/L were 94.0%, 98.2%, 95.7% and 97.5%, respectively. CONCLUSIONS: The Mindray NT-proBNP assay showed increased levels in both males and females with age, with higher levels in women. It performs well and aligns with manufacturer specifications. We recommend adjusting cutoff values based on demographic factors.

HCC subtypes based on the activity changes of immunologic and hallmark gene sets in tumor and nontumor tissues.

The prognostic role of adjacent nontumor tissue in hepatocellular carcinoma (HCC) patients is still not clear. The activity changes of immunologic and hallmark gene sets in adjacent nontumor tissues may substantially impact on prognosis by affecting proliferation of liver cells and colonization of circulating tumor cells after HCC treatment measures such as hepatectomy. We aimed to identify HCC subtypes and prognostic gene sets based on the activity changes of gene sets in tumor and nontumor tissues, to improve patient outcomes. We comprehensively revealed the activity changes of immunologic and hallmark gene sets in HCC and nontumor samples by gene set variation analysis (GSVA), and identified three clinically relevant subtypes of HCC by nonnegative matrix factorization method (NMF). Patients with subtype 1 had good overall survival, whereas those with subtype 2 and subtype 3 had poor prognosis. Patients with subtype 1 in the validation group also tended to live longer. We also identified three prognostic gene sets in tumor and four prognostic gene sets in nontumor by least absolute shrinkage and selection operator method (LASSO). Interestingly, functional enrichment analysis revealed that in nontumor tissues, genes from four gene sets correlated with immune reaction, cell adhesion, whereas in tumor tissue, genes from three gene sets closely correlated with cell cycle. Our results offer new insights on accurately evaluating prognosis-the important role of gene sets in both tumor and adjacent nontumor tissues, suggesting that when selecting for HCC treatment modality, changes in tumor and nontumor tissues should also be considered, especially after hepatectomy.

Classification and survival prediction in early-stage cirrhosis by gene expression profiling.

Liver cirrhosis has been increasingly diagnosed at an early stage owing to the non-invasive diagnostic techniques. However, it is difficult to identify patients at high risk of disease progression. Screening cirrhotic patients with poor prognosis who are most in need of surveillance is still challenging. Gene expression data GSE15654 and GSE14520 were downloaded for performing unsupervised clustering analysis. The prognostic differences between the different clusters were explored by Cox regression. Integrative analysis of gene expression signature, immune cell enrichments and clinical characterization was performed for different clusters. Two distinctive subclasses were identified in HCV-related GSE15654, and Kaplan-Meier analysis indicated that subtype 2 had lower survival rates than subtype 1 (p = 0.0399). Further analysis revealed subtype 2 had a higher density of follicular T helper cells, resting natural killer cells and M0, M2 macrophages while subtype 1 with a higher fraction of naive B cells, memory B cells, resting memory CD 4 T cells, activated natural killer cells and monocytes. 226 differentially expressed genes were identified between the two subtypes, and Reactome analysis showed the mainly enriched pathways were biological oxidations and fatty acid metabolism. Five hub genes (AKT1, RPS16, CDC42, CCND1 and PCBP2) and three significant modules were extracted from the PPI network. The results were validated in HBV-related GSE14520 cohort. We identified two subtypes of patients with different prognosis for hepatitis C-related early-stage liver cirrhosis. Bioinformatics analysis of the gene expression and immune cell profile may provide fresh insight into understanding the prognosis difference.

Antibiotic resistance genes in gut of breast-fed neonates born by caesarean section originate from breast milk and hospital ward air.

The human gut is a reservoir of antibiotic resistance genes (ARGs). Even in the absence of antibiotics, ARGs are present in large quantities in faeces of adults, children and even newborns. However, where and when ARGs are acquired remains unclear, as does the types of ARGs acquired. Herein, we recruited 82 pairs of women and their caesarean section newborns. Conventional culture methods and quantitative PCR were employed to detect nine species and six ARG types in meconia, faeces from 3-day-old newborns, amniotic fluid, colostrum, and hospital ward air samples. Furthermore, ARG transfer was explored by tracking Staphylococcus epidermidis isolated from faeces of 3-day-old newborns, colostrum and ward air samples using multi-locus sequence typing (MLST). No ARGs or microorganisms were detected in meconia or amniotic fluid. One or more ARGs were detected in 90.2% of faeces from 3-day-old newborns, and the mecA gene exhibited the highest detection rate (45.1%). ARGs were detected in 85.4% of colostra consistent with ARGs in faeces from 3-day-old newborns. Some ARGs were detected in ward air, and might also be a source of ARGs in neonatal faeces. Isolation of S. epidermidis from neonatal faeces was consistent with antibiotic resistance and gene profiles for colostrum samples. Traceability analysis of S. epidermidis showed that ARGs in neonatal faeces mainly originated from colostrum, and partly from ward air. After birth, neonates born by caesarean section obtain a variety of ARGs mainly from colostrum, and partly from ward air.

[Internal circadian clock and liver metabolism].

Circadian clock is an internal autonomous time-keeping system, including central clocks located in the suprachiasmatic nucleus (SCN) and peripheral clocks. The molecular circadian clock consists of a set of interlocking transcriptional-translational feedback loops that take the clock-controlled genes 24 h to oscillate. The core mechanism of molecular circadian clock is that CLOCK/BMAL1 dimer activates the transcription of cryptochromes (CRYs) and Periods (PERs), which act as transcriptional repressors of further CLOCK/BMAL1-mediated transcription. In addition to this basic clock, there is an additional sub-loop of REV-ERBα and RORα regulating the transcription of BMAL1. Approximately 80% protein-coding genes demonstrate significant rhythmicity. The earth rotation is responsible for the generation of the daily circadian rhythms. To coordinate metabolic balance and energy availability, almost all organisms adapt to the rhythm. Studies have shown that circadian clock integrating with metabolic homeostasis increases the efficiency of energy usage and coordinates with different organs in order to adapt to internal physiology and external environment soon. As the central organ of metabolism, the liver performs various physiological activities nearly all controlled by the circadian clock. There are multiple interactive regulation mechanisms between the circadian clock and the regulation of liver metabolism. The misalignment of metabolism with tissue circadian is identified as a high-risk factor of metabolic diseases. This article reviews the recent studies on circadian physiological regulation of liver glucose, lipid and protein metabolism and emphasizes oscillation of mitochondrial function. We also take an outlook for new methods and application of circadian clock research in the future.

[Analysis of phenotypes of Hb J-Bangkok and concomitant thalassemia].

OBJECTIVE: To analyze the hematological phenotypes of Hb J-Bangkok and concomitant thalassemia. METHODS: In total 72 397 samples were screened by using capillary electrophoresis. Samples with Hb J-Bangkok were identified by DNA sequencing and analysis of red blood cell parameters. Gap-PCR and PCR-reverse dot blotting (PCR-RDB) were used for analyzing the thalassemia genes. RESULTS: Thirty one cases of Hb J-Bangkok were identified, all of which were heterozygotes. The hematological phenotype index (Hb, mean corpuscular volume, mean corpuscular hemoglobin, Hb J-Bangkok, Hb A2) for male carriers of Hb J-Bangkok were (158±13.0) g/L, (90.1±2.3) fL, (31.1±2.5) pg, (51.3±0.7)% and (2.5±0.1)%, those for female carriers were (124±9.3) g/L, (93.3±4.9) fL, (31.1±1.6) pg, (50.9±1.1)% and (2.6±0.2)%, those for Hb J-Bangkok and an α3.7 deletion were 124 g/L, 82.1 fL, 26.1 pg, 49.4% and 2.4%, those for Hb J-Bangkok and --SEA deletion were (120±14.1) g/L, (67.7±5.7) fL, (20.5±2.6) pg, (50.1±1.9)% and (2.1±0.4)%, and those for Hb J-Bangkok and ß-thalassemia-related variants were (134±11.3) g/L, (71.6±0.9) fL, (21.7±1.0) pg, (92.7±0.6)%, (5.5±0.8)%. No Hb A was found among the Hb J-Bangkok and concomitant ß-thalassemia carriers. CONCLUSION: Hb J-Bangkok heterozygotes have normal hematological phenotypes, though they may show different hematological characteristics when concomitant with different types of thalassemia, for which genetic counseling should be provided accordingly.

A Tool for Early Prediction of Severe Coronavirus Disease 2019 (COVID-19): A Multicenter Study Using the Risk Nomogram in Wuhan and Guangdong, China.

BACKGROUND: Because there is no reliable risk stratification tool for severe coronavirus disease 2019 (COVID-19) patients at admission, we aimed to construct an effective model for early identification of cases at high risk of progression to severe COVID-19. METHODS: In this retrospective multicenter study, 372 hospitalized patients with nonsevere COVID-19 were followed for > 15 days after admission. Patients who deteriorated to severe or critical COVID-19 and those who maintained a nonsevere state were assigned to the severe and nonsevere groups, respectively. Based on baseline data of the 2 groups, we constructed a risk prediction nomogram for severe COVID-19 and evaluated its performance. RESULTS: The training cohort consisted of 189 patients, and the 2 independent validation cohorts consisted of 165 and 18 patients. Among all cases, 72 (19.4%) patients developed severe COVID-19. Older age; higher serum lactate dehydrogenase, C-reactive protein, coefficient of variation of red blood cell distribution width, blood urea nitrogen, and direct bilirubin; and lower albumin were associated with severe COVID-19. We generated the nomogram for early identifying severe COVID-19 in the training cohort (area under the curve [AUC], 0.912 [95% confidence interval {CI}, .846-.978]; sensitivity 85.7%, specificity 87.6%) and the validation cohort (AUC, 0.853 [95% CI, .790-.916]; sensitivity 77.5%, specificity 78.4%). The calibration curve for probability of severe COVID-19 showed optimal agreement between prediction by nomogram and actual observation. Decision curve and clinical impact curve analyses indicated that nomogram conferred high clinical net benefit. CONCLUSIONS: Our nomogram could help clinicians with early identification of patients who will progress to severe COVID-19, which will enable better centralized management and early treatment of severe disease.

Serum HBV pregenomic RNA is correlated with Th1/Th2 immunity in treatment-naïve chronic hepatitis B patients.

BACKGROUND AND AIM: Hepatitis B virus (HBV) load and antigens are related to the innate and adaptive immunity of chronic hepatitis B (CHB) patients. As a new HBV biomarker, the role of pregenomic RNA (pgRNA) in host immunity is not known. This study aimed to identify the relationship between serum HBV pgRNA and host immunity in CHB patients. METHODS: Two hundred twenty-five treatment-naïve CHB patients were enrolled. Serum cytokines were measured by cytokine antibody array (Luminex multiplex platform). Th1 (T-helper cell, Th) and Th2 cells were tested by flow cytometry. Serum HBV pgRNA was detected by a reverse transcription-polymerase chain reaction. RESULTS: Serum HBV pgRNA was significantly different among patients in different disease phases and significantly associated with both HBV antigens and antibodies. Serum HBV pgRNA was positively correlated with the HBsAg level (P < .001) and the presence of HBeAg (P < .001). Patients with higher HBcAb levels showed lower serum HBV pgRNA levels (P = .003). Notably, HBsAb positivity was associated with higher levels of serum HBV pgRNA in HBeAg(-) patients (P = .049). Serum HBV pgRNA was positively associated with ALT level, Th2 cell frequency, and related cytokine sCD30 (P < .001, P < .001, and P = .003, respectively), but negatively associated with Th1-related cytokine interleukin (IL)-12P70 and cytotoxic lymphocytes (CTLs) (P = .017 and P < .001, respectively). CONCLUSION: Our study confirmed the relationship between serum HBV pgRNA and host immunity. The results demonstrated that serum HBV pgRNA is positively correlated with Th2 immunity but negatively correlated with Th1 immunity, indicating that it might have a relationship with HBV antigen conversion and CTL immunodeficiency in CHB patients.

Visible-Light-Promoted C(sp3 )-H Alkylation by Intermolecular Charge Transfer: Preparation of Unnatural α-Amino Acids and Late-Stage Modification of Peptides.

Disclosed herein is the visible-light-promoted deaminative C(sp3 )-H alkylation of glycine and peptides using Katritzky salts as electrophiles. Simple reaction conditions and excellent functional-group tolerance provide a general strategy for the efficient preparation of unnatural α-amino acids and precise modification of peptides with unnatural α-amino-acid residues. Mechanistic studies suggest that visible-light-promoted intermolecular charge transfer within a glycine-Katritzky salt electron donor-acceptor (EDA) complex induces a single-electron transfer process without the assistance of photocatalyst.

Quantitative proteomics suggest a potential link between early embryonic death and trisomy 16.

Activation of extracellular signal-regulated kinase (ERK) signalling, alteration of the uterine microenvironment and a reduction in human chorionic gonadotrophin production have been linked with fetal trisomy 16-induced early embryonic death (EED). However, the detailed biological mechanism of EED remains unclear. Using quantitative proteomics we successfully screened differentially expressed proteins in the villous tissues from patients with EED and fetal trisomy 16 (EEDT16), patients with EED but normal fetal chromosomes (EEDNC) and patients undergoing elective abortion with normal fetal chromosomes (EANC) as the reference group. Compared with the reference group, we identified 337 and 220 differentially expressed proteins in EEDT16 patients and EEDNC patients respectively; these were involved in critical biological processes including immune response, superoxide metabolism, inflammatory responses and so on. We found that differential expression of immunological function-related molecules, such as human leukocyte antigen-g (HLA-G), HLA-C, Fc Fragment Of IgG Receptor III (FcγR III), also named CD16, interleukin 18 (IL-18) and transforming growth factor ß1 (TGF-ß1), might induce EED in both EEDT16 and EEDNC patients. More severe immunological dysfunction was observed in EEDT16 patients than that in EEDNC patients. Furthermore, differential expression of implantation and invasion-related molecules, such as cytochrome b-245 light chain (CYBA), neutrophil cytosol factor 2 (NCF2), Mitogen-activated protein kinase kinase kinase 4 (MAP3K4), matrix metalloproteinase 2 (MMP2), MMP9 and tumour necrosis factor α (TNF-α) might induce EED in both EEDT16 and EEDNC patients, although more severe dysfunction in the implantation and invasion ability of villous tissues was observed in EEDT16 patients.

Evidence that growth hormone can improve mitochondrial function in oocytes from aged mice.

Decline in successful conception decreases more rapidly after 38 years of age owing to follicular depletion and decreased oocyte quality. However, limited information is available regarding the underlying mechanism and the useful treatment. This study aimed to evaluate the effects of growth hormone supplementation on oocyte maturation in vivo in aged and young mice and to determine its effect on mitochondrial function. The influence of three different doses of recombinant human growth hormone (rhGH) (0.4, 0.8 and 1.6 mg/kg/day) for 8 weeks before ovarian stimulation was analyzed. Superovulated oocytes were released from the oviduct of 12-week-old and 40-week-old female C57BL/6J mice 14-16 h after administration of human chorionic gonadotropin. Ovarian follicle and morphological analysis and oocyte maturation parameters were then evaluated. This study is the first, to our knowledge, to report that medium- and high-dose rhGH significantly increases antral follicles in aged mice but anti-Müllerian hormone (AMH) levels. Furthermore, derived oocytes, MII-stage oocyte rate, ATP levels, mitochondrial membrane potential and frequencies of homogeneous mitochondrial distribution increased. In contrast, in both aged and young mice, the mtDNA copy numbers per oocyte were similar before rhGH administration, and upon saline administration, they did not differ significantly. We conclude that medium-dose rhGH supplementation before standard ovarian stimulation regimens improves oocyte quality in aged mice, probably by enhancing mitochondrial functionality.

NRDE-2, the human homolog of fission yeast Nrl1, prevents DNA damage accumulation in human cells.

The RNA helicase Mtr4 is a versatile protein that is a crucial component of several distinct RNA surveillance complexes. Here we describe a novel complex that contains Mtr4, but has a role distinct from any of those previously described. We found that Mtr4 association with the human homolog of fission yeast Nrl1, NRDE-2, defines a novel function for Mtr4 in the DNA damage response pathway. We provide biochemical evidence that Mtr4 and NRDE-2 are part of the same complex and show that both proteins play a role in the DNA damage response by maintaining low DNA double-strand break levels. Importantly, the DNA damage response function of the Mtr4/NRDE-2 complex does not depend on the formation of R loops. We show however that NRDE-2 and Mtr4 can affect R-loop signals at a subset of distinct genes, possibly regulating their expression. Our work not only expands the wide range of Mtr4 functions, but also elucidates an important role of the less characterized human NRDE-2 protein.

Effects of hemoglobin variants HbJ Bangkok, HbE, HbG Taipei, and HbH on analysis of glycated hemoglobin via ion-exchange high-performance liquid chromatography.

BACKGROUND: To explore the effects of HbJ Bangkok, HbE, HbG Taipei, and α-thalassemia HbH on the results of HbA1c assessment using ion-exchange high-performance liquid chromatography (IE-HPLC). METHODS: We enrolled five patients in which the results of the IE-HPLC HbA1c assay were inconsistent with the average levels of FBG. We performed hemoglobin capillary (Hb) electrophoresis using whole-blood samples. We also sequenced the genes encoding Hb using dideoxy-mediated chain termination and analyzed HbA1c using borate affinity HPLC (BA-HPLC) and turbidimetric inhibition immunoassay (TINIA). RESULTS: Two patients had the HbJ Bangkok variant. Hb genotypes of these patients were ß41-42 /ßJ Bangkok and ßN /ßJ Bangkok , and the content of HbJ Bangkok was 93.9% and 52.4%, respectively. The remaining three patients had the following: HbE (ßN /ßE Hb genotype, 23.6% HbE content), HbG Taipei (ßN /ßG Taipei Hb genotype, 39.4% HbG Taipei content), and α-thalassemia HbH (6.1% HbH content, 2.8% Hb Bart's content). In the patients with ß-thalassemia and HbJ Bangkok variants, the presence of the variants interfered with the results of HbA1c analyses using IE-HPLC and TINIA; in the remaining four patients, there was interference with the results of HbA1c IE-HPLC but not with the TINIA assay. There was no interference with BA-HPLC HbA1c results. CONCLUSIONS: HbJ Bangkok, HbE, HbG Taipei Hb, and α-thalassemia HbH disease cause varying degrees of interference with the analysis of HbA1c using IE-HPLC. In these patients, we suggest using methods free from such interference for the analysis of HbA1c and other indicators to monitor blood glucose levels.

RBP4 functions as a hepatokine in the regulation of glucose metabolism by the circadian clock in mice.

AIMS/HYPOTHESIS: As one of the key adipokines, retinol binding protein 4 (RBP4) is suggested to positively correlate with insulin resistance; however, not all clinical studies support this association. Although some explanations are proposed for this discrepancy, the temporal aspect of RBP4 secretion has not been considered. Aryl hydrocarbon receptor nuclear translocator-like (also known as BMAL1) and its target D site-binding protein (DBP) are both pivotal transcription factors of the circadian core clock. Given the overwhelming presence of circadian control in metabolism and the principal role of the liver in RBP4 secretion, we hypothesised that RBP4 may oscillate under the control of BMAL1 and act as a hepatokine, participating in the maintenance of glucose homeostasis by the circadian clock. METHODS: We used liver-specific Bmal1 (also known as Arntl)-knockout mice and recombinant adenoviruses expressing short-hairpin RNA (shRNA) specific for Dbp or Rbp4 in the liver. RESULTS: RBP4 displayed diurnal oscillations in the liver and plasma, which were dampened in liver-specific-Bmal1-knockout mice. BMAL1 regulated hepatic RBP4 expression via its direct target, DBP. Hepatic knockdown of RBP4 or DBP increased whole-body insulin sensitivity in mice in a time-of-day-dependent manner. Conversely, hepatic overexpression of RBP4 reversed the insulin-sensitising effects of liver-specific depletion of BMAL1. CONCLUSIONS/INTERPRETATION: Our results not only provide a novel mechanism for circadian regulation of RBP4, but also unveil a critical role of RBP4, acting as a hepatokine in the regulation of glucose metabolism by the circadian clock.

Anticancer efficacy of a nitric oxide-modified derivative of bifendate against multidrug-resistant cancer cells.

The development of multidrug resistance (MDR) not only actively transports a wide range of cytotoxic drugs across drug transporters but is also a complex interaction between a number of important cellular signalling pathways. Nitric oxide donors appear to be a new class of anticancer therapeutics for satisfying all the above conditions. Previously, we reported furoxan-based nitric oxide-releasing compounds that exhibited selective antitumour activity in vitro and in vivo. Herein, we demonstrate that bifendate (DDB)-nitric oxide, a synthetic furoxan-based nitric oxide-releasing derivative of bifendate, effectively inhibits the both sensitive and MDR tumour cell viability at a comparatively low concentration. Interestingly, the potency of DDB-nitric oxide is the independent of inhibition of the functions and expressions of three major ABC transporters. The mechanism of DDB-nitric oxide appears to be in two modes of actions by inducing mitochondrial tyrosine nitration and apoptosis, as well as by down-regulating HIF-1α expression and protein kinase B (AKT), extracellular signal-regulated kinases (ERK), nuclear factor κB (NF-κB) activation in MDR cells. Moreover, the addition of a typical nitric oxide scavenger significantly attenuated all the effects of DDB-nitric oxide, indicating that the cytotoxicity of DDB-nitric oxide is as a result of higher levels of nitric oxide release in MDR cancer cells. Given that acquired MDR to nitric oxide donors is reportedly difficult to achieve and genetically unstable, compound like DDB-nitric oxide may be a new type of therapeutic agent for the treatment of MDR tumours.

The Nrf2-ARE pathway is associated with Schisandrin b attenuating benzo(a)pyrene-Induced HTR cells damages in vitro.

As is ubiquitous in the environmental sources, benzo(a)pyrene (BaP) has been reported to induce reprotoxicity in previous studies. Toxicity to trophoblast cells may be one key factor, but evidences were absent. We speculated that BaP can induce cytotoxicity in human trophoblast HTR-8/SVneo (HTR) cells, and Schisandrin B (Sch B) as a potential protector can inhibit the cytotoxicity. MTS assay identified that BaP induced HTR cells death while Sch B played a cytoprotective role. And after Nrf2 interference, the ability of Sch B-induced cytoprotection was declined. Furthermore, PCR, western blot, ELISA, and SOD assays were found that Sch B significantly increased the mRNA and protein expression of Nrf2, HO1, NQO1, and SOD in the Nrf2-ARE pathway, and the extents of increase were declined after Nrf2 interference. These results demonstrated that the Nrf2-ARE pathway plays an important role in Sch B attenuating BaP-induced HTR cells damages in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1439-1449, 2016.

[Protective Effect of Schisandra Extract on Embryotoxicity and Reproductive Toxicity in Early Pregnant Rats Exposed to Benzo [a] pyrene].

OBJECTIVE: To observe protective effects of Schisandra extract (SE) on embryotoxicity and reproductive toxicity of early pregnant rats exposed to Benzo[a]pyrene (Bap). METHODS: Pregnant rat model was prepared using periodic screening cage method. Totally 50 female pregnant SD rats were divided into five groups by randomized block design according to the weight, i.e., the BaP model group, the low dose SE group, the middle dose SE group, the high dose SE group, the normal control group, 10 rats in each group. Rats in the BaP model group were administered with BaP at a daily dose of 2 mg/kg by gastrogavage. Rats in low, middle, and high dose SE groups were administered by gastrogavage with BaP (at a daily dose of 2 mg/kg) plus SE at a daily dose of 40, 200, and 1 000 mg/kg, respectively. Equal volume of olive oil was administered to rats in the normal control group by gastrogavage. All medication was performed for 8 successive days. Changes of rat body weight in each period were observed. The uterus embryonic total quality and ovary quality were measured, and organ index calculated. The number of corpus luteum, the number of embryo implantation, and the number of absorbed embryo were statistically calculated respectively. The implantation rate and the absorbed embryos rate were calculated. Serum levels of human chorionic gonadotrophin ß (ß-HCG) and progesterone (PROG) were detected by ELISA. RESULTS: Compared with the normal control group, the weight of 9-day pregnant rats, the number of embryo implantation, the uterus embryonic total index, ovary index, serum levels of ß-HCG and PROG all decreased in the Bap model group with significant difference (P < 0.05, P < 0.01). Compared with the Bap model group, body weight, the uterus embryonic total index, and the PROG level increased in 3 dose SE groups (P < 0.05, P < 0.01). Ovary index and serum ß-HCG increased in middle and high dose SE groups (P < 0.05, P < 0.01). The number of implantation obviously increased in the high dose SE groups (P < 0.01). CONCLUSION: SE could reduce the embryotoxicity and reproductive toxicity of early pregnant rats exposed to Benzo[a]pyrene.

[Analysis of reoperation for infertility women with tubal pregnancy after conservative surgery].

OBJECTIVE: To evaluate the cause of infertility and tubal abnormality in women of tubal pregnancy after conservative treatment with laparotomy or laparoscopy through a combination of laparoscopy, hysteroscopic tubal catheterization and hydrotubation. METHODS: Laparoscopy was performed to observe pelvic adhesions, tube shape, fimbriated extremity of fallopian and other factors related with infertility for 37 inpatients with infertility after tubal pregnancy and undergoing conservative surgery during December 2008 and October 2010. Meanwhile, hysteroscopic tubal catheterization and hydrotubation were performed with laparoscopy to examine tube patency. RESULTS: Among them, 97.3% had tube infertility caused by tube abnormality and adhesions, or tube obstruction alone or concurrently. For all tubes, tube obstruction accounted for 79.7% (59/74) , fimbrial occlusion of fallopian tube 54.1% (40/74) and tube abnormality 52.7% (39/74) . Pelvic adhesion occurred at a rate of 89.2% and there were I degree (21.6%), II degree (32.4%), III degree (35.1%) and IV degree (0). For tubes with pregnancy history, 48.6% showed tube abnormality, 45.9% fimbrial occlusion of fallopian tube and 75.7% (28/37) tube obstruction. Comparatively, for the tubes without pregnancy history, 56.8%showed tube abnormality, 62.2%fimbrial occlusion of fallopian tube and 86.5%tube obstruction. No significant difference existed in tube shape, umbrella end and tube obstruction between the tubes with pregnancy history and those without pregnancy history. Neither statistically significant difference was found in adhesion degree, tube shape, umbrella end and tube obstruction of diseased and normal tubes between laparotomy and laparoscopy groups. CONCLUSION: Infertility of women after tubal pregnancy and conservative surgery is mainly caused by abnormal tube including pelvic adhesion, tube morphological abnormality and tube obstruction. No marked inter-group difference exists in fertility damage after conservative surgery with laparotomy or laparoscopy.