ROCK Inhibitor Y-27632 Promotes Human Retinal Pigment Epithelium Survival by Altering Cellular Biomechanical Properties

Purpose:

Dysfunction or death of retinal pigment epithelial (RPE) cells is a common pathogenesis of various types of retinal degenerative diseases. Recent reports indicated that ROCK pathway inhibitors regulate cell proliferation or apoptosis in a cell-type-dependent manner. Here, we aim to investigate the effect of ROCK inhibitor Y-27632 on the human retinal pigment epithelium (RPE) in vitro.

Methods:

Cell proliferation and apoptosis were analyzed by CCK-8 and flow cytometry respectively. Cell proliferation markers were detected by immunofluorescence and western blot. Cell morphology was evaluated using scanning electron microscopy. The topography and biomechanical properties of living cells were assessed using atomic force microscope (AFM). In addition, cytoskeleton and epithelial-mesenchymal transition (EMT) markers were detected by western blot and immunofluorescence.

Results:

30μM Y-27632 significantly promoted cell proliferation and decreased apoptosis. Compared with control group, human retinal pigment epithelial cell line ARPE-19 cells treated with 30μM Y-27632 exhibited significantly decreased cytomembrane roughness (Ra: 41.04±1.63nm vs. 24.41±0.75nm, P<0.01; Rq: 51.56±2.03nm vs. 30.81±0.95nm, P<0.01) and increased elasticity modulus (16.66±0.83KPa vs. 32.55±1.48KPa, P<0.01). In addition, the inhibition of ROCK activity by Y-27632 caused cell elongation and reorganization of microfilaments and microtubules of cytoskeletons.

Conclusion:

Taken together, our data demonstrated that Y-27632 could alter biomechanical properties and reorganized cytoskeletons to promote RPE cell survival. These results are an important step toward the future application of Y-27632 in retinal degenerative diseases.

Association of endothelin-1 gene polymorphisms with essential hypertension in a Chinese population

Endothelin-1 (ET-1) is the most potent endogenous vasoconstrictor and is involved in several vascular disorders such as hypertension. Its strong interaction with other vasoactive hormone systems suggests that the ET-1 gene (EDN1) is a potential candidate molecule that influences the risk of developing hypertension. Recently, two single nucleotide polymorphisms in EDN1 have been reported to be associated with hypertension: Lys198Asn and 3A/4A (-134delA) located in the 5'-untranslated region. To determine the association of these two polymorphisms with hypertension, we genotyped patients and controls (N = 537) and compared the allele and genotype frequencies between groups. There was no significant difference in the genotype frequencies of these two polymorphisms between healthy controls and hypertension patients. Although previous reports have revealed a significant interaction between the END1 Lys198Asn (G/T) polymorphism and body mass index in association with hypertension, no such relationship was observed in the present study. Further, we compared blood pressure among hypertensive subjects and observed that neither systolic nor diastolic blood pressure was significantly associated with variations in the genotypes of the two single nucleotide polymorphisms. In summary, these two END1 polymorphisms do not appear to affect the development of hypertension in the Chinese population.

A SAR-based mechanistic study on the combined toxicities of sulfonamides and quorum sensing inhibitors on Escherichia coli

Quorum sensing inhibitors (QSIs) are promising alternatives to antibiotics, but they are discharged into the environment after their use cycle. This poses joint effects on the organisms in the environment. Therefore, it is of great importance to study the combined toxicities of QSIs and antibiotics. In this study, we investigated the single and combined toxicities of four potential QSIs and 11 sulfonamides (SAs) on Escherichia coli. The results revealed that the single toxicities of SAs were greater than those of QSIs, and the toxicities were found positively related to the binding energies (E_bind) with their target proteins, for both antibiotics and QSIs. The combined toxicities of the binary mixtures were observed to be either antagonism or addition. The antagonism could be explained by the phenomenon that QSIs changed SAs molecules into ionic forms, preventing the SA molecules entering the bacteria. Furthermore, it was found that the ratios of the effective concentration (the actual concentration involved in the interaction with the proteins) in the antagonistic cases were higher than those in the additive cases. This study would benefit both rational use of the drug combination and ecological risk assessment of antibiotics and QSIs in the real environment.

Dietary supplementation with tributyrin prevented weaned pigs from growth retardation and lethal infection via modulation of inflammatory cytokines production, ileal expression, and intestinal acetate fermentation

Weanling pigs, with an underdeveloped intestine and immature immune system, are usually subjected to depressed feed intake, growth retardation, and postweaning diarrhea. The aim of this study was to determine 1) the growth response of weaned pigs to supplemental tributyrin (TB) and 2) the potential effects and mechanisms of TB in modulating immune responses of lipopolysaccharide (LPS)-challenged piglets. A total of 240 piglets (Duroc × Large White × Landrace) were weaned at 21 d of age to a control (basal diet), supplemented with antibiotics (AB; +AB), supplemented with TB (+TB), or with supplemental AB and TB (+AB+TB) diets, with 10 replicate pens (6 piglets/pen) per diet. At 49 d of age, male pigs from the control and +TB groups were intraperitoneally injected with LPS (25 μg/kg BW) or saline ( = 6) and sacrificed at 4 h after injection to collect blood, intestine, and digesta samples for biochemical analysis. There were higher ( < 0.05) feed intake and lower ( < 0.05) percentage of negative growth piglets in the +TB groups than in the control group during the first week after weaning. For piglets without LPS challenge, there were higher ( < 0.05) ileal fibroblast growth factor 19 () mRNA abundance and total bile acid concentrations in the +TB groups than in the control group, whereas downregulated ( < 0.05) expression was observed in the +TB groups after LPS challenge. Lipopolysaccharide challenge in the control group increased ( < 0.05) plasma tumor necrosis factor α and IL-6 concentrations and colonic amount and decreased ( < 0.05) colonic goblet cells and colonic and cecal acetate concentrations, with no differences ( > 0.05) observed between +TB groups following LPS challenge. Taken together, dietary supplementation with TB prevented growth retardation through stimulating the appetite of weaned pigs and protected piglets against lethal infection via modulation of inflammatory cytokines production, ileal expression, and intestinal acetate fermentation.

Superconductivity in HfTe5 across weak to strong topological insulator transition induced via pressures

Recently, theoretical studies show that layered HfTe₅ is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe₅ are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe₅ with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe₅ crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe₅ transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe₅ is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.

Topologically Entangled Rashba-Split Shockley States on the Surface of Grey Arsenic

We discover a pair of spin-polarized surface bands on the (111) face of grey arsenic by using angle-resolved photoemission spectroscopy (ARPES). In the occupied side, the pair resembles typical nearly-free-electron Shockley states observed on noble-metal surfaces. However, pump-probe ARPES reveals that the spin-polarized pair traverses the bulk band gap and that the crossing of the pair at Γ[over ¯] is topologically unavoidable. First-principles calculations well reproduce the bands and their nontrivial topology; the calculations also support that the surface states are of Shockley type because they arise from a band inversion caused by crystal field. The results provide compelling evidence that topological Shockley states are realized on As(111).

PKR2 and β-catenin genes regulates pancreatic cancer chemosensitivity

OBJECTIVE

Pancreas is a well developed glandular organ lying behind the stomach. Cancer arises in this organ are difficult to identify in the initial stages, even in advanced stages it shows non-specific symptoms, and it is difficult to prognosis. Since they are identified and treated in the last stage, they are less responsive to chemotherapy. Therefore, it is important to study the proteins that are involved in regulating chemosensitivity and chemoresistance.

MATERIALS AND METHODS

Initially, using KRAS mutant mice, we developed initial and advanced stage of pancreatic cancer. And we analyzed the expression of PKR2 and β-catenin in different pathological stages of pancreatic cancer using Immunohistology and Western blotting.

RESULTS

The histology of the tissue nature confirms and helps to categorize cancer, which shows enlarged nucleus in initial stages and shows clustering of cells in advanced stages. Immunohistological and Western blotting analyzes show prominent increasing in the expression of PKR2 and β-catenin as the tumor develops to the next stages. On the course of initial treatment with cisplatin we find out that PKR2 and β-catenin regulate the chemosensitivity with under-expression when compared with respective controls. In the advanced stages of pancreatic cancer with cisplatin treatment, we observed chemoresistance behavior with overexpression, especially for β-catenin.

CONCLUSIONS

The results conclude that using PKR2 and β-catenin we are able to assess the chemosensitivity and chemoresistance nature of pancreatic cancer.

Fabrication of HA/PEI-functionalized carbon dots for tumor targeting, intracellular imaging and gene delivery

Carbon quantum dots (CDs) as emerging carbon nano-materials have attracted tremendous attention in biomedical fields due to unique properties.

Data integration for identification of important transcription factors of STAT6-mediated cell fate decisions

Data integration has become a useful strategy for uncovering new insights into complex biological networks. We studied whether this approach can help to delineate the signal transducer and activator of transcription 6 (STAT6)-mediated transcriptional network driving T helper (Th) 2 cell fate decisions. To this end, we performed an integrative analysis of publicly available RNA-seq data of Stat6-knockout mouse studies together with STAT6 ChIP-seq data and our own gene expression time series data during Th2 cell differentiation. We focused on transcription factors (TFs), cytokines, and cytokine receptors and delineated 59 positively and 41 negatively STAT6-regulated genes, which were used to construct a transcriptional network around STAT6. The network illustrates that important and well-known TFs for Th2 cell differentiation are positively regulated by STAT6 and act either as activators for Th2 cells (e.g., Gata3, Atf3, Satb1, Nfil3, Maf, and Pparg) or as suppressors for other Th cell subpopulations such as Th1 (e.g., Ar), Th17 (e.g., Etv6), or iTreg (e.g., Stat3 and Hif1a) cells. Moreover, our approach reveals 11 TFs (e.g., Atf5, Creb3l2, and Asb2) with unknown functions in Th cell differentiation. This fact together with the observed enrichment of asthma risk genes among those regulated by STAT6 underlines the potential value of the data integration strategy used here. Thus, our results clearly support the opinion that data integration is a useful tool to delineate complex physiological processes.

Gut microbiome remodeling induces depressive-like behaviors through a pathway mediated by the host's metabolism

Major depressive disorder (MDD) is the result of complex gene-environment interactions. According to the World Health Organization, MDD is the leading cause of disability worldwide, and it is a major contributor to the overall global burden of disease. However, the definitive environmental mechanisms underlying the pathophysiology of MDD remain elusive. The gut microbiome is an increasingly recognized environmental factor that can shape the brain through the microbiota-gut-brain axis. We show here that the absence of gut microbiota in germ-free (GF) mice resulted in decreased immobility time in the forced swimming test relative to conventionally raised healthy control mice. Moreover, from clinical sampling, the gut microbiotic compositions of MDD patients and healthy controls were significantly different with MDD patients characterized by significant changes in the relative abundance of Firmicutes, Actinobacteria and Bacteroidetes. Fecal microbiota transplantation of GF mice with 'depression microbiota' derived from MDD patients resulted in depression-like behaviors compared with colonization with 'healthy microbiota' derived from healthy control individuals. Mice harboring 'depression microbiota' primarily exhibited disturbances of microbial genes and host metabolites involved in carbohydrate and amino acid metabolism. This study demonstrates that dysbiosis of the gut microbiome may have a causal role in the development of depressive-like behaviors, in a pathway that is mediated through the host's metabolism.

Down-regulation of tumor suppressor PDCD4 expression in endometrium of adenomyosis patients

OBJECTIVE

Adenomyosis is a common benign gynecological disease which has some malignant behaviors. Programmed cell death 4 (PDCD4) is a newly identified tumor suppressor gene which lowly expresses in various cancers. However, the expression status of PDCD4 in endometrium of adenomyosis patients has not been investigated. The aim of this study is to assess the expression levels of PDCD4 in endometrium of normal controls and adenomyosis patients.

METHODS

The expression of PDCD4 in endometrium of normal controls and eutopic or ectopic endometrium of patients with adenomyosis was evaluated with quantitative real-time PCR, western blot and immunohistochemistry. In addition, the levels of serum estradiol and progesterone in normal controls and adenomyosis patients were detected using electrochemiluminescence immunoassay.

RESULTS

The results showed that PDCD4 mainly expressed in the cytoplasma of glandular epithelium of control endometrium and varied during the cycle changes of endometrium, which may be regulated by changing concentrations of progesterone in the menstrual cycle. Compared with the proliferative phase of control endometrium, PDCD4 expression was down-regulated in proliferative phase of eutopic endometrium or ectopic endometrium, and there was no cyclic variation of PDCD4 expression in eutopic endometrium of adenomyosis patients due to progesterone resistance.

CONCLUSION

These results suggest that PDCD4 may be involved in the pathogenesis of adenomyosis, which will provide a novel strategy for the early diagnosis and new therapeutic target of adenomyosis.

A recombinant plasmid of composite cysteine proteinase inhibitor/glyceraldehyde-3-phosphate dehydrogenase gene of periodic Brugia malayi functions on DNA immunity in the host

OBJECTIVES

Both cysteine proteinase inhibitors (CPIs) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) play important roles in the pathogenesis of parasites and their relationship with the hosts. We constructed a new eukaryotic recombinant expression plasmid pcDNA3.1(+)-BmCPI/BmGAPDH of periodic Brugia malayi for investigation of the DNA vaccine-elicited immune responses.

MATERIALS AND METHODS

We cloned a gene encoding the CPIs and GAPDH from periodic B. malayi into vector pcDNA3.1. The composited plasmid or the control was injected into the tibialis anterior muscle of the hind leg in BALB/c mice, respectively. The target genes were detected by reverse transcription-polymerase chain reaction in muscle tissues. The stimulation index (SI) of T-lymphocyte proliferation and the levels of interferon-gamma (INF-g) and interleukin-4 ( IL-4) in serum were detected by thiazolyl blue tetrazolium blue and enzyme-linked immunosorbent assays.

RESULTS

The pcDNA3.1(+)-BmCPI/BmGAPDH was amplified from muscle tissues of the mice after immunisation. The SI of the immunised group was significantly higher than that of the two control groups (P < 0.05). The levels of INF-g and IL-4 of pcDNA3.1(+)-BmCPI/BmGAPDH group were both higher than those of the two control groups (P < 0.05). The level of INF-g of pcDNA3.1(+)-BmCPI/BmGAPDH group was significantly higher than that of pcDNA3.1(+)-BmCPI/CpG group (P < 0.05).

CONCLUSIONS

We conclude that the recombinant plasmid pcDNA3.1(+)-BmCPI/BmGAPDH could elicit specific humoural and cellular immune responses in mice.

Translation and validation of a Chinese version of the Mandibular Function Impairment Questionnaire

To adapt the English version of the Mandibular Function Impairment Questionnaire (MFIQ) for Chinese-speaking patients with temporomandibular disorder (TMD) and to evaluate its validity and reliability. In total, 352 patients diagnosed with TMD according to the research diagnostic criteria for TMD (RDC/TMD) Axis I were included in this study. The psychometric evaluation included reliability, which was evaluated by internal consistency (Cronbach's alpha coefficient), and test-retest reliability and validity, which were tested by content and construct validity. Because the content validity of item 11 (kissing) was low (0·12), this item was excluded in subsequent analyses. For exploratory factor analysis, three factors were extracted, accounting for 63·6% of the variance. All items had factor loadings above 0·4. Two models were tested by confirmatory factor analysis, and the two-factor model was adopted (χ(2) /df = 2·279, root mean square error of approximation (RMSEA) = 0·086, comparative fit index (CFI) = 0·910). Internal reliability (coefficient alpha values of 0·925 and 0·720 for each factor) and test-retest reliability (ICCfactor1 = 0·895, 95% CIfactor1 = 0·869-0·918, ICCfactor2 = 0·720, 95% CIfactor2 = 0·645-0·783) of the Chinese MFIQ were excellent. A reliable and valid Chinese version of the MFIQ was constructed for the evaluation of Chinese patients with TMD after some modification of the English version of the MFIQ.

Observation of Weyl nodes and Fermi arcs in tantalum phosphide

A Weyl semimetal possesses spin-polarized band-crossings, called Weyl nodes, connected by topological surface arcs. The low-energy excitations near the crossing points behave the same as massless Weyl fermions, leading to exotic properties like chiral anomaly. To have the transport properties dominated by Weyl fermions, Weyl nodes need to locate nearly at the chemical potential and enclosed by pairs of individual Fermi surfaces with non-zero Fermi Chern numbers. Combining angle-resolved photoemission spectroscopy and first-principles calculation, here we show that TaP is a Weyl semimetal with only a single type of Weyl fermions, topologically distinguished from TaAs where two types of Weyl fermions contribute to the low-energy physical properties. The simple Weyl fermions in TaP are not only of fundamental interests but also of great potential for future applications. Fermi arcs on the Ta-terminated surface are observed, which appear in a different pattern from that on the As-termination in TaAs and NbAs.

Benzylation of heterocyclic N-oxides via direct oxidative cross-dehydrogenative coupling with toluene derivatives

A novel cross-dehydrogenative coupling (CDC) of heterocyclic N-oxides with toluene derivatives has been disclosed.

Hyaluronic acid functionalized nitrogen-doped carbon quantum dots for targeted specific bioimaging

Schematic illustration of the preparation of HA-CQDs (A) and the following bioimaging application (B).

Raman scattering investigation of the quasi-one-dimensional superconductor Ta₄Pd₃Te₁₆

We have performed polarized Raman scattering measurements on the newly discovered superconductor Ta4Pd3Te16 (T(c) = 4.6 K). We observe 28 out of 33 Raman active modes, with frequencies in good accordance with first-principles calculations. Although most of the phonons observed vary only slightly with temperature and do not exhibit any asymmetric profile that would suggest strong electron-phonon coupling, the linewidth of the A(g) phonon mode at 89.9 cm(-1) shows an unconventional increase with temperature decreasing, which is possibly due to a charge-density-wave transition or the emergence of charge-density-wave fluctuations below a temperature estimated to fall in the 140-200 K range.