KCNQ/Kv7 channel activator flupirtine protects against acute stress-induced impairments of spatial memory retrieval and hippocampal LTP in rats

Spatial memory retrieval and hippocampal long-term potentiation (LTP) are impaired by stress. KCNQ/Kv7 channels are closely associated with memory and the KCNQ/Kv7 channel activator flupirtine represents neuroprotective effects. This study aims to test whether KCNQ/Kv7 channel activation prevents acute stress-induced impairments of spatial memory retrieval and hippocampal LTP. Rats were placed on an elevated platform in the middle of a bright room for 30 min to evoke acute stress. The expression of KCNQ/Kv7 subunits was analyzed at 1, 3 and 12 h after stress by Western blotting. Spatial memory was examined by the Morris water maze (MWM) and the field excitatory postsynaptic potential (fEPSP) in the hippocampal CA1 area was recorded in vivo. Acute stress transiently decreased the expression of KCNQ2 and KCNQ3 in the hippocampus. Acute stress impaired the spatial memory retrieval and hippocampal LTP, the KCNQ/Kv7 channel activator flupirtine prevented the impairments, and the protective effects of flupirtine were blocked by XE-991 (10,10-bis(4-Pyridinylmethyl)-9(10H)-anthracenone), a selective KCNQ channel blocker. Furthermore, acute stress decreased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) at Ser9 in the hippocampus, and flupirtine inhibited the reduction. These results suggest that the KCNQ/Kv7 channels may be a potential target for protecting both hippocampal synaptic plasticity and spatial memory retrieval from acute stress influences.

Mesenchymal stromal cells infusions improve refractory chronic graft versus host disease through an increase of CD5+ regulatory B cells producing interleukin 10

Refractory chronic graft-versus-host disease (cGVHD) is a significant complication resulting from allogeneic hematopoietic stem cell transplantation (HSCT). Mesenchymal stromal cells (MSCs) have shown promise for treating refractory cGVHD, but the favorable effects of MSCs therapy in cGVHD are complex and not fully understood. In this prospective clinical study, 20 of 23 cGVHD patients had a complete response or partial response in a 12-month follow-up study. The most marked improvements in cGVHD symptoms were observed in the skin, oral mucosa and liver. Clinical improvement was accompanied by a significantly increased number of interleukin (IL)-10-producing CD5+ B cells. Importantly, CD5+ B cells from cGVHD patients showed increased IL-10 expression after MSCs treatment, which was associated with reduced inflammatory cytokine production by T cells. Mechanistically, MSCs could promote the survival and proliferation of CD5+ regulatory B cells (Bregs), and indoleamine 2, 3-dioxygenase partially participates in the MSC-mediated effects on Breg cells. Thus, CD5+ Breg cells may have an important role in the process of MSC-induced amelioration of refractory cGVHD and may provide new clues to reveal novel mechanisms of action for MSCs.

First Report of Alternaria heveae Causing Black Leaf Spot of Rubber Tree in China

Rubber tree (Hevea brasiliensis Muell. Arg.) is an important industrial crop of tropical areas for natural rubber production. In October 2013, foliar spots (0.1 to 0.4 mm in diameter), black surrounded by a yellow halo, and with lesions slightly sunken were observed on the rubber tree leaf in a growing area in Heikou County of Yunnan Province. Lesion tissues removed from the border between symptomatic and healthy tissue were surface sterilized in 75% ethanol and air-dried, plated on PDA plates, and incubated at 28°C with alternating day/night cycles of light. The pathogen was observed growing out of many of the leaf pieces, and produced abundant conidia. Colonies 6.1 cm in diameter developed on potato carrot agar (PCA) after 7 days, with well-defined concentric rings of growth. Colonies on PCA were composed of fine, dark, radiating, surface and subsurface hyphae. Conidia produced in PCA culture were mostly solitary or in short chains of 2 to 5 spores, long ovoid to clavate, and light brown, 40 to 81.25 × 8 to 20 μm (200 colonies were measured), with 3 to 6 transverse septa and 0 to 2 longitudinal or oblique septa. Morphological characteristics were similar to those described for Alternaria heveae (3,4). A disease of rubber tree caused by Alternaria sp. had been reported in Mexico in 1947 (2). DNA of Ah01HK13 isolate was extracted for PCR and sequencing of the ITS region with ITS1 and ITS4 primers was completed. From the BLAST analysis, the sequence of Ah01HK13 (GenBank Accession No. KF953884), had 97% similarity to A. dauci, 96% identical to A. macrospora (AY154701.1 and DQ156342.1, respectively), indicating the pathogen belonged to Alternaria genus. According to morphological characteristics, this pathogen was identified as A. heveae. Pathogenicity of representative isolate, Ah01HK13 was confirmed using a field rubber tree inoculation method. Three rubber plants (the clone of rubber tree Yunyan77-4) were grown to the copper-colored leaf stage and inoculated by spraying spore suspension (concentration = 10⁴ conidia/ml) to the copper-colored leaves until drops were equally distributed on it using manual pressure sprayer. Three rubber plants sprayed with sterile distilled water were used as controls. After inoculation, the plants were covered with plastic bags. The plastic bags were removed after 2 days post-inoculation (dpi) and monitored daily for symptom development (1). The experiment was repeated three times. The typical 0.1 to 0.4 mm black leaf spots were observed 7 dpi. No symptoms were observed on control plants. A fungus with the same colony and conidial morphology as A. heveae were re-isolated from leaf lesions on inoculated rubber plants, but not from asymptomatic leaves of control plants, fulfilling Koch's postulates. Based on these results, the disease was identified as black spot of rubber tree caused by A. heveae. To our knowledge, this is the first report of A. heveae on rubber tree in China. References: (1) Z. Y. Cai et al. Microbiol Res. 168:340, 2013. (2) W. J. Martin. Plant Dis. Rep. 31:155, 1947. (3) E. G. Simmons. Mycotaxon 50:262, 1994. (4) T. Y. Zhang. Page 111 in: Flora Fungorum Sinicorum: Alternaria, Science Press, Beijing, 2003.

Structure of AlN on Si (111) Deposited with Metal Organic Vapor Phase Epitaxy

The surface morphology and structure of AlN deposited by metal organic vapor phase epitaxy (MOVPE) on Si (111) at growth temperatures ranging from 825 to 1175°C was investigated. Transmission electron microscopy (TEM), reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS) techniques were used to study the resulting film structure. Growth at high temperatures but less than ∼1100°C, resulted in a wire texture with some degree of in-plane alignment with (0001)AlN/ /(111)Si, < 10 0>AlN//< 11>Si, and 110>AlN//<10>Si. Deposition at temperatures greater than 1100°C results in single crystal films consisting of domains 60 nm across with an aspect ratio near unity. Growth below1100°C leads to degraded crystal quality with the grains developing random rotational misalignments around the AlN [0001] axis. Growth at lower temperatures produces islands elongated along the [110] direction. At the growth temperature of 825°C, the aspect ratio of the islands increased to 3 and a width of 25 nm. Cross-sectional TEM reveals that these islands are faceted due to slow growth on the {1 01}planes.

Reproductive isolation between two darter species is enhanced and asymmetric in sympatry

Robust reproductive isolation was found between the rainbow darter Etheostoma caeruleum and the orangethroat darter Etheostoma spectabile, as more offspring were produced when conspecific males and females were crossed as compared with heterospecific crosses. Furthermore, fewer eggs resulted from heterospecific crosses involving sympatric E. spectabile females than those using allopatric E. spectabile females, while a similar pattern was not observed in heterospecific crosses using E. caeruleum females. These results suggest that reinforcement, i.e. selection for pre-zygotic reproductive barriers driven by reduced hybrid fitness, may have contributed to the evolution and maintenance of reproductive barriers between these potentially hybridizing species in sympatry.

Investigation into in vitro and in vivo models using intestinal epithelial IPEC-J2 cells and Caenorhabditis elegans for selecting probiotic candidates to control porcine enterotoxigenic Escherichia coli

AIMS

To identify a fast, economic and reliable method for preselecting lactic acid-producing bacterial (LAB) isolates to control enterotoxigenic Escherichia coli (ETEC).

METHODS AND RESULTS

Two assays with porcine intestinal epithelial IPEC-J2 cells or Caenorhabditis elegans for selecting effective probiotic candidates were compared. Both assays were based on measuring death of cells or worms caused by ETEC strain JG280. Six of 13 LAB isolates showed ≥50% protection in each assay, among which only four isolates (≥50% protection) were consistently selected by both assays. Isolate CL9 (Lactobacillus reuteri) was further studied. It reduced gene expression of estA, estB and elt in JG280 in both assays. Furthermore, the isolate protected IPEC-J2 and C. elegans from cell and worm death caused by STa, STb or LT enterotoxin expressed in E. coli DH5α. CL9 also promoted host defensive responses by decreasing IL-8 and increasing IL-10 production in IPEC-J2 cells and expression of antimicrobial peptide genes clec-60, clec-85 in C. elegans.

CONCLUSIONS

Caenorhabditis elegans is useful for preselecting probiotic candidates to control ETEC after initial screening with IPEC-J2 cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

A combination of IPEC-J2 cell and C. elegans assays can improve the effectiveness in preselecting probiotic candidates.

CRP gene polymorphism predicts post-stroke functional outcome in Han Chinese

OBJECTIVES

Stroke is a major cause of long-term disability and morbidity worldwide. C-reactive protein (CRP), an inflammatory marker, has been reported to be an independent predictor of functional outcome after ischemic stroke (IS). Because several single nucleotide polymorphisms (SNPs) at the CRP locus have been linked with elevated CRP levels, we hypothesized that CRP genetic variation might be associated with functional disability in patients after first-ever IS.

METHODS

A total of 1716 patients from western China with first-ever IS were genotyped for the CRP SNPs rs1130864 and rs1800947 using the ligation detection reaction method. Functional outcome was assessed 3 months after IS using the modified Rankin Scale. Then, we tested the association of CRP SNP genotypes with stroke outcome after adjusting for non-genetic factors.

RESULTS

Our data showed a significant association between the T allele of rs1130864 and poor functional outcome in IS patients. In addition, the presence of TT+CT genotypes of rs1130864 strongly predicted functional disability within the first 3 months, even after adjusting for potential confounders.

CONCLUSIONS

Our study indicates that SNP rs1130864 in the CRP gene is an independent predictor of 3-month functional outcome in patients with first-onset IS in a Han Chinese population. Further studies in different ethnic groups are needed to validate our findings.

Small molecules modulating biogenesis or processing of microRNAs with therapeutic potentials

MicroRNAs (miRNAs) are single-stranded non-coding RNAs with the ability to regulate gene expression at post-transcriptional level. Typically, miRNAs function by binding to the 3' untranslated regions (UTR) of target mRNAs, leading to the degradation or repressed expression of target genes. It is estimated that miRNAs are involved in almost every genetic pathway and the regulation of miRNAs plays important roles in physiological and pathological processes. Small molecules that can regulate miRNAs have great potential as probes to explore miRNAs-mediated regulatory network. Small-molecule regulators of disease-related miRNAs also hold the potential as novel therapeutic agents. Based on the screening systems developed in recent years, several small-molecule regulators have been identified as specific or universal regulators of miRNAs. Therapeutic potentials of these small molecules have also been demonstrated. A general review on the reported small molecules modulating the biogenesis or function of miRNAs will be presented in this paper, with emphasis on the screening methods, proposed mechanism of action and the therapeutic potentials of these small molecules.

siRNA targeting prohibitins inhibits proliferation and promotes apoptosis of gastric carcinoma cell line SGC7901 in vitro and in vivo

In the present study we investigate the effects of small interfering RNA (siRNA)-mediated silencing of prohibitins (Phbs) gene expressions on gastric carcinoma cell proliferation and apoptosis in vitro and in vivo. Firstly, Phbs proteins in five human gastric carcinoma cell lines were evaluated by Western blotting. Then three siRNA sequences targeting Phbs were designed and transfected into the cancer cell line with the highest Phbs protein expressions. The cell proliferation and apoptosis were analyzed by MTT and flow cytometry methods. In vivo, the effects of siRNAs on the proliferation and apoptosis were assayed in xenografted tumors of nude mice. Phbs proteins were expressed highest in gastric carcinoma cell line SGC7901. The cell proliferation significantly decreased upon Phbs silencing. The cell percentage in S phase was significantly lower in Phbs silenced groups, and the apoptotic cell ratio was significantly higher. siRNA targeting Phbs significantly inhibited the growth of the xenografted tumors. Further, Bcl-2 and Bax was respectively downregulated and upregulated after the Phbs silencing in the xenografted tumors. Caspase-3 and caspase-9 activities were significantly enhanced in the Phbs-silenced tumors. In summary, siRNA-mediated silencings of Phbs inhibit proliferation and promotes apoptosis of gastric carcinoma cells SGC7901 in vitro and in vivo, suggesting key roles of Phbs in the development of SGC7901 cell line.

The FEN1 E359K germline mutation disrupts the FEN1-WRN interaction and FEN1 GEN activity, causing aneuploidy-associated cancers

Polymorphisms and somatic mutations in Flap Endonuclease 1 (FEN1), an essential enzyme involved in DNA replication and repair, can lead to functional deficiencies of the FEN1 protein and a predisposition to cancer. We identified a FEN1 germline mutation which changed residue E359 to K in a patient whose family had a history of breast cancer. We determined that the E359K mutation, which is in the protein-protein domain of FEN1, abolished the interaction of FEN1 with Werner Syndrome protein (WRN), an interaction which is critical for resolving stalled DNA replication forks. Furthermore, although the flap endonuclease activity of FEN1 E359K was unaffected, it failed to resolve bubble structures, which requires the FEN1 gap dependent endonuclease (GEN) activity. To determine the etiological significance of E359K, we established a mouse model containing this mutation. E359K mouse embryonic fibroblasts (MEF) were more sensitive to DNA cross-linking agents that cause replication forks to stall. Cytological analysis suggested that the FEN1-WRN interaction was also required to for telomere stability; mutant cell lines had fragile telomeres, increased numbers of spontaneous chromosomal anomalies and higher frequencies of transformation. Moreover, the incidence of cancer was significantly higher in mice homozygous for FEN1 E359K than in wild-type mice, suggesting that the FEN1 E359K mutation is oncogenic.

Galectin-1 overexpression promotes progression and chemoresistance to cisplatin in epithelial ovarian cancer

This study was performed to investigate the role of galectin-1 (Gal-1) in epithelial ovarian cancer (EOC) progression and chemoresistance. Tissue samples from patients with EOC were used to examine the correlation between Gal-1 expression and clinical stage of EOC. The role of Gal-1 in EOC progression and chemoresistance was evaluated in vitro by siRNA-mediated knockdown of Gal-1 or lentivirus-mediated overexpression of Gal-1 in EOC cell lines. To elucidate the molecular mechanisms underlying Gal-1-mediated tumor progression and chemoresistance, the expression and activities of some signaling molecules associated with Gal-1 were analyzed. We found overexpression of Gal-1 in advanced stages of EOC. Knockdown of endogenous Gal-1 in EOC cells resulted in the reduction in cell growth, migration, and invasion in vitro, which may be caused by Gal-1's interaction with H-Ras and activation of the Raf/extracellular signal-regulated kinase (ERK) pathway. Additionally, matrix metalloproteinase-9 (MMP-9) and c-Jun were downregulated in Gal-1-knockdown cells. Notably, Gal-1 overexpression could significantly decrease the sensitivities of EOC cells to cisplatin, which might be ascribed to Gal-1-induced activation of the H-Ras/Raf/ERK pathway and upregulation of p21 and Bcl-2. Taken together, the results suggest that Gal-1 contributes to both tumorigenesis and cisplatin resistance in EOC. Thus, Gal-1 is a potential therapeutic target for EOC.

Adenosine 5'-monophosphate ameliorates D-galactosamine/lipopolysaccharide-induced liver injury through an adenosine receptor-independent mechanism in mice

D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced lethality and acute liver failure is dependent on endogenously produced inflammatory cytokines. Adenosine has been proven to be a central role in the regulation of inflammatory response. It is not entirely clear that which adenosine action is actually crucial to limiting inflammatory tissue destruction. Here we showed that GalN/LPS challenge elevated hepatic adenosine and induced lethality in adenosine receptor-deficient mice with equal efficiency as wild-type mice. In GalN/LPS-treated mice, pretreatment with adenosine 5'-monophosphate (5'-AMP) significantly elevated hepatic adenosine level and reduced mortality through decreasing cytokine and chemokine production. In RAW264.7 cells, 5'-AMP treatment inhibited the production of inflammatory cytokines, which is not mediated through adenosine receptors. 5'-AMP failed to attenuate LPS-induced nuclear factor-κB (NF-κB) p65 nuclear translocation, but reduced LPS-induced recruitment of NF-κB p65 to inflammatory gene promoters and decreased LPS-induced enrichment of H3K4 dimethylation at the tumor necrosis factor-α (TNF-α) promoter, which was involved in 5'-AMP-induced elevation of cellular adenosine and a decline of methylation potential. In vitro biochemical analysis revealed that adenosine directly attenuated recruitment of NF-κB to the TNF-α and interleukin-6 promoters. Our findings demonstrate that 5'-AMP-inhibiting inflammatory response is not mediated by adenosine receptors and it may represent a potential protective agent for amelioration of LPS-induced liver injury.

Structure and photoluminescence characteristics of europium(iii) doped in CaAl2Si2O8phosphors

A series of Eu³⁺activated CaAl₂Si₂O₈phosphors have been synthesized at 1350 °C in air, and their photoluminescence properties have been investigated as a function of activator concentrations.

Relationship between exposure to extremely low-frequency electromagnetic fields and breast cancer risk: a meta-analysis

OBJECTIVE

To comprehensively analyze the relationship between human exposure to extremely low frequency electromagnetic fields (ELF-EMFs) and breast cancer and to discuss the potential risk of ELF-EMFs to human breast cancer.

MATERIALS AND METHODS

Sixteen research reports of case-control studies which were published from 2000 to 2007 were collected. The fixed effect model (FEM) or the random effect model (REM) was chosen to calculate total ORs depending on the outcomes of the test of homogeneity (Q test): the subgroup was analyzed with the menopause and the non-menopause.

OUTCOME

Sixteen research outcome was ORDL = 1.10, 95% CI = (1.01, 1.20), the OR(MH) of the non-menopause status group was 1.25, 95% CI = (1.05, 1.49), the OR(MH) of the menopause status group was OR(MH) = 1.04, 95% CI = (0.93, 1.18).

CONCLUSION

The authors found that ELF-EMFs may be increase the risk of human breast cancer. The women's exposure to ELF-EMFs may be the risk factor of breast cancer when they are non-menopausal.

Epidemiologic investigation of polycystic ovarian syndrome (PCOS) in Han ethnic women of reproductive age in Liaoning Province, China

OBJECTIVE

To determine the incidence of polycystic ovary syndrome (PCOS) among Han women of reproductive age in Liaoning Province in Northeastern China, based on the Revised Rotterdam 2003 criteria.

MATERIALS AND METHODS

A retrospective cohort study was carried out on 1,600 women using questionnaires, physical examination, ultrasonography, and biochemical indices (aged = 19 to 45 years; n = 1,600). PCOS patients were identified using the Revised Rotterdam 2003 criteria.

RESULTS

A total of 132 Han women of reproductive age were diagnosed with PCOS, with a prevalence of 8.25%. The prevalence of menstrual dysfunction was as follows: 97 patients (73.48%) had abnormal menstruation, three (2.27%) had polymenorrhea, and 94 (71.21%) had oligomenorrhea. Up to 64 patients (48.48%) had androgen excess, 42 (31.82%) had biochemical evidence of androgen excess, and 34 (25.76%) had clinical androgen excess. Up to 34 patients (25.76%) were obese (body mass index [BMI] > or = 25) and 19 (14.39%) had hirsutism (F-G scoring > or = 6). A total of 127 patients (96.22%) were diagnosed with PCOS via ultrasonography, 67 of whom (50.76%) had a unilateral polycystic ovary and 60 (45.46%) had bilateral polycystic ovaries.

CONCLUSIONS

The prevalence of PCOS in this study population was 8.25%, with an infertility rate of 27.8%. The classical manifestation of PCOS is PCO, abnormal menstruation, and obesity. The high-risk factors of PCOS include high free testosterone index, homeostasis model assessment-insulin resistance (HOMA-IR), increased serum testosterone and androstenedione, decreased sex hormone-binding globulin, long history of infertility, menarche later than 16 years old, and failure to have regular menstruation within two years.

Kinetics of serological responses in influenza A(H7N9)-infected patients correlate with clinical outcome in China, 2013

The novel avian influenza A(H7N9) infection has recently emerged to cause severe respiratory illness in China. The objectives of this study were to define the kinetics of the antibody responses in patients with influenza A(H7N9) disease and to correlate these kinetics with clinical outcome. Serial serum samples were obtained at intervals of three to four days from 18 patients with virologically confirmed A(H7N9) disease in Shanghai. We determined the kinetics of the haemagglutination inhibition (HI) and A(H7H9) pseudotype neutralisation antibody (Nab) responses and correlated these with clinical outcomes. Most patients had robust serological responses by both HI and Nab tests. Taking into account censoring due to time of testing and death, the median time from onset of illness to Nab titre ≥1:40 was 14 days (95% confidence interval (CI): 11–18 days) in the fatal cases and 10.5 days (95% CI: 7–12) in the survivors (p=0.003). The two groups did not differ in initial Nab titres, but the rate of increase in Nab titres was significantly faster for survivors by approximately 10-fold per 15 days (p=0.007). Early and rapid induction of Nab was correlated significantly with better clinical outcome.