345 LOSS OF Brm AND Baf170, COMPONENTS OF THE ATP-DEPENDENT CHROMATIN REMODELING COMPLEX, FACILITATES REPROGRAMMING OF SOMATIC CELL

The SWI/SNF [SWItch/Sucrose NonFermentable; also known as BAF (Brg/Brahma-associated factors)] ATP-dependent chromatin remodelling complexes are epigenetic modifiers that change the structure of chromatin, and thereby modulate gene transcription. The BAF chromatin remodeling complexes undergo progressive changes in subunit composition during cellular differentiation. In embryonic stem cells (ESC), BAF complex, esBAF, contains Brg1 and Baf155, which are crucial for ESC self-renewal and also facilitate induced pluripotent stem cell (iPSC) reprogramming from somatic cells. Here we sought to determine the roles of somatic BAF components (Brm and Baf170, homologues of Brg1 and Baf155, respectively) in mouse iPSC reprogramming through shRNA-mediated knockdown studies. We found that the expression of Brm and Baf170 were inhibited in reprogramming by Janus kinase/signal transducer and activator of transcription 3 (Jak/Stat3) activity, which is essential for pluripotency establishment. We further found that knockdown of Brm and Baf170 in mouse somatic cells promotes reprogramming efficiency. Specifically, loss of Brm and Baf170 during early (Days 3 and 6 after initial iPSC induction) and later-stage (Day 9) reprogramming, respectively, improves the numbers of iPSC colonies formed. These also led to significant upregulation of pluripotent genes, including Sox2, Nanog, Fgf5, and Tbx3. Although the somatic Brm and Baf170 are believed to be absent in ESC, the expression levels of Nanog and Tbx3 were increased significantly by knockdown of either Brm or Baf170 in ESC. Finally, we showed that inhibition of these somatic BAF components also promotes complete reprogramming of partially reprogrammed cells (pre-iPSC). These data suggest that inhibiting somatic BAF complex improved complete reprogramming by facilitating the activation of the pluripotency circuitry. A reduced activity of the somatic BAF complex constitutes part of the Stat3 regulated epigenetic changes during pluripotency establishment.

Overexpression of p300 correlates with poor prognosis in patients with cutaneous squamous cell carcinoma

BACKGROUND

It has been suggested that the p300 transcriptional coactivator participates in the regulation of a wide range of cell biological processes, and mutations in p300 have been identified in various cancers.

OBJECTIVES

To investigate p300 expression in cutaneous squamous cell carcinoma (cSCC) tissues and its effect on the outcome of patients with cSCC.

METHODS

Immunohistochemistry (IHC) was performed on a tissue microarray to investigate p300 expression levels in cSCC tissues. Receiver operating characteristic (ROC) curve analysis, Kaplan-Meier plots and a Cox proportional hazards regression model were used to analyse the data.

RESULTS

Based on the ROC curves, we defined the cut-off score for high p300 expression as > 55% of tumour cells positively stained. High expression of p300 was observed in 86 of 165 (52·1%) of the cSCC samples and six of 30 (20%) of the adjacent normal skin tissue samples (P < 0·001). High expression of p300 was positively correlated with lymph node metastasis (P = 0·006) and advanced clinical stage (P < 0·001). In univariate survival analysis, high expression of p300 was correlated with poor patient outcomes in terms of recurrence-free survival (P = 0·006) and overall survival (P < 0·001). Moreover, p300 expression was evaluated as an independent prognostic factor in a multivariate analysis (P = 0·004).

CONCLUSIONS

Our results indicate that high p300 expression is associated with aggressive features of cSCC and suggest that p300 expression, as examined by IHC, will be a promising biomarker for predicting clinical outcomes in patients with cSCC.

Enhanced formation and impaired degradation of neutrophil extracellular traps in dermatomyositis and polymyositis: a potential contributor to interstitial lung disease complications

Dermatomyositis (DM) and polymyosits (PM) are systemic autoimmune diseases whose pathogeneses remain unclear. Neutrophil extracellular traps (NETs) are reputed to play an important role in the pathogenesis of autoimmune diseases. This study tests the hypothesis that NETs may be pathogenic in DM/PM. Plasma samples from 97 DM/PM patients (72 DM, 25 PM) and 54 healthy controls were tested for the capacities to induce and degrade NETs. Plasma DNase I activity was tested to further explore possible reasons for the incomplete degradation of NETs. Results from 35 DM patients and seven PM patients with interstitial lung disease (ILD) were compared with results from DM/PM patients without ILD. Compared with control subjects, DM/PM patients exhibited a significantly enhanced capacity for inducing NETs, which was supported by elevated levels of plasma LL-37 and circulating cell-free DNA (cfDNA) in DM/PM. NETs degradation and DNase I activity were also decreased significantly in DM/PM patients and were correlated positively. Moreover, DM/PM patients with ILD exhibited the lowest NETs degradation in vitro due to the decrease in DNase I activity. DNase I activity in patients with anti-Jo-1 antibodies was significantly lower than in patients without. Glucocorticoid therapy seems to improve DNase I activity. Our findings demonstrate that excessively formed NETs cannot be degraded completely because of decreased DNase I activity in DM/PM patients, especially in patients with ILD, suggesting that abnormal regulation of NETs may be involved in the pathogenesis of DM/PM and could be one of the factors that initiate and aggravate ILD.

Preparation and malachite green adsorption behavior of polyurethane/chitosan composite foam

A series of Polyurethane/Chitosan composite foam with different chitosan content of 5–25 wt% was prepared, and their adsorption performance of malachite green (MG) in aqueous solutions was investigated by pH values, contact time, temperatures and chitosan content. It was observed that Polyurethane/Chitosan composite foam exhibited well-developed open cell structures. Malachite green adsorption capacities of the composite foam increased with the increment of chitosan content in composite foam. Polyurethane/Chitosan composite foam with 20% chitosan content exhibited a maximum removal capacity of 16.67 mg/g and 95.60% MG removal efficiency. In addition, MG adsorption capacities of composite foam increased with pH value increase, 30℃ was the optimum temperature, which affects the adsorption process, and the adsorption maximum was attained within 12 hours. The result of SEM showed the prepared composite foam possess well-developed open cell structures. The MG adsorption kinetics and equilibrium isotherm of the composite foam were well described with the pseudo-second order kinetic model and Langmuir isotherm model, respectively. This work provided an attractive adsorbent for removing of the hazardous materials from water.

Combined analysis of νμ disappearance and νμ→νe appearance in MINOS using accelerator and atmospheric neutrinos

We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(μ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.

Synthesis and Properties of a Novel Intumescent Flame Retardant and its Application in LLDPE

In this study, a novel phosphorus-containing flame retardant (IFR) of spirocyclic pentaerythritol diphosphonate dinitroguanidine (SPDD) was successfully synthesized, which was characterized by 1H NMR, 31P NMR and FTIR spectra. At the same time, the SPDD was used in LLDPE to prepare flame-retardant materials whose flammability and thermal behavior were studied by thermogravimetric analysis (TGA), limiting oxygen index (LOI) and scanning electron microscopy (SEM). The TGA data showed that SPDD could effectively enhance the thermal stability and char residue of LLDPE/IFR composite. And with the increase of SPDD, the LOI value of LLDPE/IFR increases obviously. When SPDD reached 30 wt%, the LOI value of LLDPE/IFR reaches 31 %. The SEM also shows the surface of intumescent chars of LLDPE/IFR (30 %) has many sphere-like swollen bubbles.

Selective inhibition of protein kinase C β2 attenuates the adaptor P66 Shc-mediated intestinal ischemia-reperfusion injury

Apoptosis is a major mode of cell death occurring during ischemia–reperfusion (I/R) induced injury. The p66^Shc adaptor protein, which is mediated by PKCβ, has an essential role in apoptosis under oxidative stress. This study aimed to investigate the role of PKCβ₂/p66^Shc pathway in intestinal I/R injury. In vivo, ischemia was induced by superior mesenteric artery occlusion in mice. Ruboxistaurin (PKCβ inhibitor) or normal saline was administered before ischemia. Then blood and gut tissues were collected after reperfusion for various measurements. In vitro, Caco-2 cells were challenged with hypoxia–reoxygenation (H/R) to simulate intestinal I/R. Translocation and activation of PKCβ₂ were markedly induced in the I/R intestine. Ruboxistaurin significantly attenuated gut damage and decreased the serum levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Pharmacological blockade of PKCβ₂ suppressed p66^Shc overexpression and phosphorylation in the I/R intestine. Gene knockdown of PKCβ₂ via small interfering RNA (siRNA) inhibited H/R-induced p66^Shc overexpression and phosphorylation in Caco-2 cells. Phorbol 12-myristate 13-acetate (PMA), which stimulates PKCs, induced p66^Shc phosphorylation and this was inhibited by ruboxistaurin and PKCβ₂ siRNA. Ruboxistaurin attenuated gut oxidative stress after I/R by suppressing the decreased expression of manganese superoxide dismutase (MnSOD), the exhaustion of the glutathione (GSH) system, and the overproduction of malondialdehyde (MDA). As a consequence, ruboxistaurin inhibited intestinal mucosa apoptosis after I/R. Therefore, PKCβ₂ inhibition protects mice from gut I/R injury by suppressing the adaptor p66^Shc-mediated oxidative stress and subsequent apoptosis. This may represent a novel therapeutic approach for the prevention of intestinal I/R injury.

Maggot debridement therapy for the treatment of diabetic foot ulcers: a meta-analysis

OBJECTIVE

To assess the potential efficacy of maggot debridement therapy (MDT) compared with standard care for diabetic foot ulcers (DFUs).

METHOD

A meta-analysis was performed on the evidence for MDT for DFUs. Databases, including PubMed, Web of Science, the Cochrane Library, EMbase, EBSCOhost, Springer Link, ScienceDirect and Ovid-Medline, were electronically searched for randomised controlled trials, case-control studies and controlled clinical trials, up to 31 December 2012, and relevant references of the included articles were also manually searched. The literature was screened, the data were extracted and the methodological quality of the included studies was assessed. Meta-analyses were performed on the included data, for the outcomes healing rate, time to healing, incidence of infection, amputation rate and antibiotic-free days or antibiotics usage.

RESULTS

Overall, four studies comparing MDT with standard therapy on a total of 356 participants were included. The results of meta-analyses suggested that the MDT group was significantly superior to the control group in the percentage of DFUs to achieve full healing (RR=1.8, 95%CI=1.07; 3.02; p=0.03), amputation rate (RR=0.41, 95%CI=0.20; 0.85; p=0.02), time to healing (RR=-3.70, 95%CI=-5.76; -1.64; p=0.0004) and number of antibiotic-free days (126.8 ± 30.3 days vs 81.9 ± 42.1 days; p=0.001); however, collated differences in incidence of infection after intervention revealed no evidence of a difference between the MDT and control groups (RR=0.82, 95%CI=0.65; 1.04, p=0.10).

CONCLUSION

Although MDT may be a scientific and effective therapy in treatment of DFUs, the evidence is too weak to routinely recommend it for treatment. Large studies and sample sizes are needed to assess the efficacy and safety of MDT in the treatment of DFUs.

DECLARATION OF INTEREST

There were no external sources of funding for this study. The authors have no conflicts of interest to declare with regard to this work or its contents. X. Tian and X.M. Liang contributed equally to this work.

Cost-effectiveness of a 12-dose regimen for treating latent tuberculous infection in the United States

SETTING

A large randomized controlled trial recently showed that for treating latent tuberculous infection (LTBI) in persons at high risk of progression to tuberculosis (TB) disease, a 12-dose regimen of weekly rifapentine plus isoniazid (3HP) administered as directly observed treatment (DOT) can be as effective as 9 months of daily self-administered isoniazid (9H).

OBJECTIVES

To assess the cost-effectiveness of 3HP compared to 9H.

DESIGN

A computational model was designed to simulate individuals with LTBI treated with 9H or 3HP. Costs and health outcomes were estimated to determine the incremental costs per active TB case prevented and per quality-adjusted life year (QALY) gained by 3HP compared to 9H.

RESULTS

Over a 20-year period, treatment of LTBI with 3HP rather than 9H resulted in 5.2 fewer cases of TB and 25 fewer lost QALYs per 1000 individuals treated. From the health system and societal perspectives, 3HP would cost respectively US$21,525 and $4294 more per TB case prevented, and respectively $4565 and $911 more per QALY gained.

CONCLUSIONS

3HP may be a cost-effective alternative to 9H, particularly if the cost of rifapentine decreases, the effectiveness of 3HP can be maintained without DOT, and 3HP treatment is limited to those with a high risk of progression to TB disease.

Changes in phosphatidylinositol 3-kinase 55 kDa gamma expression and subcellular localization may be caspase 6 dependent in paraquat-induced SH-SY5Y apoptosis

The neurotoxin paraquat (PQ) causes apoptosis of dopaminergic neurons in mammalian cell culture and animal models, mimicking an important pathological feature of Parkinson's disease (PD). The phosphoinositide 3-kinase (PI3K)/Akt pathway is critical for several major survival signals in central nervous system neurons. Phosphatidylinositol 3-kinase 55 kDa gamma (p55PIK) is a regulatory subunit of PI3Ks with important roles in cell proliferation, antiapoptosis, and cell cycle progression. However, p55PIK involvement in mechanisms regarding progression and maintenance of neurodegenerative diseases is largely undetermined. We used PQ-induced apoptosis in human dopaminergic SH-SY5Y cells to investigate the association between p55PIK expression levels, subcellular location, and apoptosis. p55PIK expression was reduced in SH-SY5Y cells and p55PIK messenger RNA and protein expression levels were decreased after PQ treatment. Apoptosis induced by PQ was associated with caspase activation and decreased p55PIK expression. Restoration of p55PIK expression was observed after coincubation with a caspase inhibitor. Overexpressed full-length p55PIK in SH-SY5Y and human embryonic kidney 293 cells showed specific distribution in the nucleus and was cleaved in vitro by recombinant caspase 6 (C6), but not C3 and C7. A p55PIK construct lacking 24 N-terminal amino acids (N24) was tested for the presence of a potential C6-recognizable sequence and was found to express its proteins outside the nucleus. The results suggest that p55PIK may be involved in PQ-induced apoptosis signal transduction and that N24 is crucial for p55PIK subcellular localization. Thus, p55PIK could be a substrate of activated C6 during apoptosis, leading to loss of original biological functions and redistribution to disturb cell cycle progression.

A conserved extraordinarily long serine homopolymer in Dictyostelid amoebae

Eukaryotic protein sequences often contain amino-acid homopolymers that consist of a single amino acid repeated from several to dozens of times. Some of these are functional but others may persist largely because of high expansion rates due to DNA slippage. However, very long homopolymers with over a hundred repeats are very rare. We report an extraordinarily long homopolymer consisting of 306 tandem serine repeats from the single-celled eukaryote Dictyostelium discoideum, which also has a multicellular stage. The gene has a paralog with 132 repeats and orthologs, also with high serine repeat numbers, in various other Dictyostelid species. The conserved gene structure and protein sequences suggest that the homopolymer is functional. The high codon diversity and very poor alignment of serine codons in this gene between species similarly indicate functionality. This is because the serine homopolymer is conserved despite much DNA sequence change. A survey of other very long amino-acid homopolymers in eukaryotes shows that high codon diversity is the rule, suggesting that these too may be functional.

Fine mapping of qhir1 influencing in vivo haploid induction in maize

Production of haploids by the in vivo haploid induction method has now become routine for generating new inbred lines in maize. In previous studies, a major quantitative trait locus (QTL) (qhir1) located in bin 1.04 was detected, explaining up to 66 % of the genotypic variance for haploid induction rate (HIR). Our objectives were to (1) fine-map qhir1 and (2) identify closely linked markers useful for marker-assisted breeding of new inducers. For this purpose, we screened a mapping population of 14,375 F2 plants produced from a cross between haploid inducer UH400 and non-inducer line 1680 to identify recombinants. Based on sequence information from the B73 reference genome, markers polymorphic between the two parents were developed to conduct fine mapping with these recombinants. A progeny test mapping strategy was applied to accurately determine the HIR of the 14 recombinants identified. Furthermore, F3 progeny of recombinant F2 plants were genotyped and in parallel evaluated for HIR. We corroborated earlier studies in that qhir1 has both a significantly positive effect on HIR but also a strong selective disadvantage, as indicated by significant segregation distortion. Altogether, we were able to narrow down the qhir1 locus to a 243 kb region flanked by markers X291 and X263.

CASP-9 gene functional polymorphisms and cancer risk: a large-scale association study plus meta-analysis

We investigated the association between CASP-9 polymorphisms and susceptibility to neoplasm. Fourteen studies with a total of 2733 neoplasm cases and 3352 healthy controls were included. Meta-analysis showed that the rs4645981 T allele and the rs4645981 T allele carrier were positively associated with neoplasm susceptibility [odds ratio (OR) = 1.43, 95% confidence interval (95%CI) = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009, respectively]. However, the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might decrease the risk of cancer (OR = 0.72, 95%CI = 0.58-0.89, P = 0.003; OR = 0.76, 95%CI = 0.63-0.92, P = 0.004; OR = 0.20, 95%CI = 0.09-0.45, P < 0.0001; OR = 0.21, 95%CI = 0.06-0.75, P = 0.02, respectively). There was no significant association between rs1263, rs1052571, rs2308950, rs4645978, rs4645980, rs4645982, and rs4646018 and cancer risk (all P > 0.05). In conclusion, this meta-analysis suggests that CASP-9 gene polymorphisms are involved in the pathogenesis of various cancers. The rs4645981 T allele and the rs4645981 T allele carrier might increase the risk of cancer, but the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might be protective.

First Report of Impatiens necrotic spot virus on Hiemalis Begonia (Begonia × hiemalis) in Canada

Impatiens necrotic spot virus (INSV) is a member of the genus Tospovirus, and one of the prevalent viruses infecting ornamental plants, including begonia. Since the late 1980s, it has caused dramatic and unusual diseases on many flower crops, leading to considerable economic losses to the greenhouse floriculture industry (1). The western flower thrips, Frankliniella occidentalis (Pergande), is the only species currently known to vector INSV (1). In spring 2012, stunted plant growth and necrotic spots were observed on leaves of all Hiemalis begonias (Begonia × hiemalis Fotsch.) in a greenhouse in southwest Ontario, Canada. Initial symptoms were mosaic patterns, followed by necrotic spots on leaves, concentric rings, then necrotic areas on flowers, stem and vein necrosis, and finally stunting and burning of foliage similar to damage caused by sunburn or chemical injury. Thrips were observed colonizing nearby begonia plants. Leaf tissue from five symptomatic plants tested positive for INSV in a double-antibody sandwich (DAS)-ELISA with INSV-specific ImmunoStrips (Agdia Inc., Elkhart, IN). To confirm this, five of the leaf samples that were found to be positive for INSV in ELISA tests were mechanically inoculated to 10 plants of Hiemalis Begonia. Out of the 10 inoculated plants, eight produced necrotic local lesions and necrotic spots that are typical of INSV infection, followed by systemic infection of upper leaves 30 days after inoculation. The presence of INSV in the eight symptomatic plants was confirmed using the commercial INSV Pocket Diagnostic Kit (Forsite Diagnostics Ltd., York, UK) according to the manufacturer's instructions. Results showed that all eight symptomatic plants were positive for INSV. The other two plants were asymptomatic and tested negative for INSV. To further confirm the identity of this virus, total RNAs were isolated from symptomatic leave of begonia plants using TRIzol reagent (Invitrogen, Life Technologies Grand Island, NY) and amplified using reverse transcription (RT)-PCR analysis. A pair of primers was designed based on the consensus sequence of the N gene for a number of isolates retrieved from GenBank. These primers were INSV-F2286 (5'CCAAGCTCAACATGTTTAGC 3', nt positions 2286 to 2305 of AB109100) and INSV-R2604 (5'ACTGCATCTTGCCTATCCTT 3', nt positions 2664 to 2683 of AB109100). The expected amplification product of 398 bp was obtained, and was cloned into the vector pGEM-T Easy (Promega Corp., Madison, WI). Two clones were sequenced using the vector primer M13Forward. The sequences of these two clones were identical and the sequence was deposited in GenBank (Accession No. JX846907). BLAST analysis indicated that the sequence was 98 to 99% identical to INSV isolates from Japan (AB109100), the United States (D00914), and the Netherlands (X66972). To our knowledge, this is the first report of INSV infection in Begonia × hiemalis in Canada. This finding provides further evidence for the spread of the virus within North America. Further studies are required to determine the impact of INSV on the begonia industry in Canada and to determine viable management strategies, if necessary. Reference: (1) M. L. Daughtrey et al. Plant Dis. 81:1220, 1997.

Acute dietary zinc deficiency before conception compromises oocyte epigenetic programming and disrupts embryonic development

Recent findings show that zinc is an important factor necessary for regulating the meiotic cell cycle and ovulation. However, the role of zinc in promoting oocyte quality and developmental potential is not known. Using an in vivo model of acute dietary zinc deficiency, we show that feeding a zinc deficient diet (ZDD) for 3-5 days before ovulation (preconception) dramatically disrupts oocyte chromatin methylation and preimplantation development. There was a dramatic decrease in histone H3K4 trimethylation and global DNA methylation in zinc deficient oocytes. Moreover, there was a 3-20 fold increase in transcript abundance of repetitive elements (Iap, Line1, Sineb1, Sineb2), but a decrease in Gdf9, Zp3 and Figla mRNA. Only 53% and 8% of mature eggs reached the 2-cell stage after IVF in animals receiving a 3 and 5 days ZDD, respectively, while a 5 day ZDD in vivo reduced the proportion of 2-cells to 49%. In vivo fertilized 2-cell embryos cultured in vitro formed fewer (38%) blastocysts compared to control embryos (74%). Likewise, fewer blastocyst and expanded blastocyst were collected from the reproductive tract of zinc deficient animals on day 3.5 of pregnancy. This could be due to a decrease in Igf2 and H19 mRNA in ZDD blastocyst. Supplementation with a methyl donor (SAM) during IVM restored histone H3K4me3 and doubled the IVF success rate from 17% to 43% in oocytes from zinc deficient animals. Thus, the terminal period of oocyte development is extremely sensitive to perturbation in dietary zinc availability.

Meta-analysis demonstrates association of XRCC1 genetic polymorphism Arg399Gln with esophageal cancer risk in the Chinese population

We made a meta-analysis of the association between X-ray cross-complementing gene 1 (XRCC1) genetic polymorphism Arg399Gln and esophageal cancer (EC) risk. Statistical analysis was performed with the Review Manager version 4.2.8 software program and STATA version 11.0. We selected 16 case-control studies for this meta-analysis, including 3591 EC cases and 5752 controls. Overall, the Gln399 allele was not associated with EC risk, compared with the Arg399 allele in the populations included in the analysis. However, stratified analysis revealed that the Gln399 allele was associated with increased EC risk among the Chinese population in a recessive model [odds ratio (OR) = 1.42; 95% confidence interval (95%CI) = 1.07-1.90; P = 0.02 for heterogeneity] and by homozygote contrast (OR = 1.43; 95%CI = 1.05-1.96; P = 0.02 for heterogeneity), particularly for the tumor histology of squamous cell carcinoma (OR = 1.46; 95%CI = 1.10-1.95 for the recessive model and OR = 1.42; 95%CI = 1.03-1.95 for the homozygote contrast). We conclude that the XRCC1 Arg399Gln polymorphism has potential as a biomarker for EC susceptibility in the Chinese population, particularly for squamous cell carcinoma.

A literature-based systematic HuGE review and meta-analysis show that CASP gene family polymorphisms are associated with risk of lung cancer

The caspase (CASP) gene family is known to be involved in apoptosis, cytokine maturation, cell growth, and differentiation. A large number of single nucleotide polymorphisms (SNPs) in the CASP gene family have been increasingly recognized as important regulators in the development of lung cancer. However, this specific association is still controversial. In this Human Genome Epidemiology review and meta-analysis, we summarized the available evidence associating lung cancer with the CASP gene family. Seven studies, which included 1155 lung cancer cases and 1120 healthy controls, met the inclusion criteria and were included in our meta-analysis. In seven studies, 19 different SNPs have been studied in seven CASP genes, including CASP-1, -2, -5, -7, -8, -9, and -10. Meta-analysis results showed positive associations between heterozygote (A/G) of rs507879 in the CASP-5 gene, the T allele of rs12415607 in the CASP-7 gene, and the T allele and T carrier (C/T+T/T) of rs4645981 in the CASP-9 gene with lung cancer susceptibility [odds ratio (OR) = 1.83, 95% confidence interval (95%CI) = 1.07-3.12, P = 0.03; OR = 1.18, 95%CI = 1.02-1.37, P = 0.03; OR = 1.43, 95%CI = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009; respectively]. However, we found that homozygote (G/G) of rs2227310 in the CASP-7 gene, del allele, heterozygote (ins/del), and del carrier (ins/del + del/del) of rs3834129 in CASP-8 could be protective factors for lung cancer (OR = 0.17, 95%CI = 0.14-0.21, P = 0.0003; OR = 0.83, 95%CI = 0.72-0.97, P = 0.02; OR = 0.74, 95%CI = 0.64-0.85, P < 0.0001; OR = 0.81, 95%CI = 0.71-0.93, P = 0.002; respectively). In conclusion, based on this meta-analysis, we suggest that SNPs in CASP-5, -7, -8, and -9 are associated with susceptibility to lung cancer.

Protective effect of the nitric oxide pathway in L-citrulline renal ischaemia-reperfusion injury in rats

To observe the protective effects of L-citrulline on the renal I/R injury and elucidate the mechanisms involved, 48 rats were randomized into eight groups: Group 1: sham operated; Group 2: I/R (45 min renal ischaemia and 24 h reperfusion); Group 3: I/R + L-citrulline (300 mg/kg, i.g.); Group 4: I/R + L-citrulline (600 mg/kg, i.g.); Group 5: I/R + L-citrulline (900 mg/kg, i.g.); Group 6: I/R + normal saline (NS, i.g.); Group 7: I/R + N sup ω nitro-L-arginine ester (L-NAME, 20 mg/kg, i.p.); Group 8: I/R + L-citrulline (900 mg/kg, i.g.) + L-NAME (20 mg/ kg, i.p.). At the end of the reperfusion period, serum was collected and the kidneys underwent histological and biochemical examinations. Our results showed that pre-treatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the renal injury caused by I/R. Moreover, L-citrulline prevented induction of lipid peroxidation and increased the activity of superoxide dismutase and the levels of glutathione and nitric oxide. The I/R-induced decreases in total nitric oxide synthase activity, inducible nitric oxide activity, constitutive nitric oxide activity and endothelial nitric oxide protein expression in the renal cortex were significantly prevented. However, the L-citrulline-mediated protection was significantly antagonized by co-administration of L-NAME. These results suggested that L-citrulline administration exhibited significant protection against renal I/R injury. This protective effect, at least in part, via up-regulation of the endothelial nitric oxide protein expression and constitutive nitric oxide synthase activity, maintained production of nitric oxide at the basal level.

Dynamic-average Characteristics of Late Wave of Auditory Evoked Potentials for Synaptic Malfunction Rat Model

The aim of this study is to investigate dynamic characteristics of late wave of auditory evoked potentials (AEPs) in synaptic malfunction rat model. Two dynamic characteristics relative to cognitive function were investigated which are dynamic latency and dynamic amplitude of P1. Synaptic malfunction model was made by Sprague-Dawley rats via microinjecting beta-amyloid protein (A-beta) into hippocampal CA1 area of rat. Dynamic AEPs with high background noise were recorded for both model and normal rats in experiments. Dynamic late wave were taken from dynamic AEPs using third-order correlation and wavelet technology. The dynamic-average latency and the dynamic-average amplitude of P1 in a small time window (5s) were performed as dynamic index in this study, which remain most of dynamic information because the average window was very small. Then dynamic-average latency and the dynamic-average latency of P1 were compared between synaptic malfunction rat and normal group. The results of this study have demonstrated that: (1) the dynamic-average latency of P1 for model rats prolonged remarkably than control (P<0.01, alpha =0.05); (2) the dynamic-average amplitude of P1 for model rats increased remarkably than control(P<0.01,alpha =0.05). The conclusion is that dynamic-average latency and dynamic-average amplitude in the synaptic malfunction rats model has obvious difference with normal group.

Zinc depletion causes multiple defects in ovarian function during the periovulatory period in mice

Shortly before ovulation, the oocyte acquires developmental competence and granulosa cells undergo tremendous changes including cumulus expansion and luteinization. Zinc is emerging as a key regulator of meiosis in vitro, but a complete understanding of zinc-mediated effects during the periovulatory period is lacking. The present study uncovers the previously unknown role of zinc in maintaining meiotic arrest before ovulation. A zinc chelator [N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN)] caused premature germinal vesicle breakdown and associated spindle defects in denuded oocytes even in the presence of a phosphodiesterase 3A inhibitor (milrinone). TPEN also potently blocked cumulus expansion by blocking induction of expansion-related transcripts Has2, Ptx3, Ptgs2, and Tnfaip6 mRNA. Both meiotic arrest and cumulus expansion were rescued by exogenous zinc. Lack of cumulus expansion is due to an almost complete suppression of phospho-Sma- and Mad-related protein 2/3 signaling. Consistent with a decrease in phospho-Sma- and Mad-related protein 2/3 signaling, TPEN also decreased cumulus transcripts (Ar and Slc38a3) and caused a surprising increase in mural transcripts (Lhcgr and Cyp11a1) in cumulus cells. In vivo, feeding a zinc-deficient diet for 10 d completely blocked ovulation and compromised cumulus expansion. However, 42.5% of oocytes had prematurely resumed meiosis before human chorionic gonadotropin injection, underscoring the importance of zinc before ovulation. A more acute 3-d treatment with a zinc-deficient diet did not block ovulation but did increase the number of oocytes trapped in luteinizing follicles. Moreover, 23% of ovulated oocytes did not reach metaphase II due to severe spindle defects. Thus, acute zinc deficiency causes profound defects during the periovulatory period with consequences for oocyte maturation, cumulus expansion, and ovulation.

Regulation of radiosensitivity by HDAC inhibitor trichostatin A in the human cervical carcinoma cell line Hela

Histone deacetylase (HDAC) inhibitors play an important role in inducing growth arrest, differentiation, and/or apoptosis in cancer cells. Given their ability to disrupt critical biological processes in cancer cells, these agents are emerging as potential therapeutics for cancer. Recently, it has been identified that HDAC inhibitors can also efficiently enhance the radiation sensitivity of cells, both in vitro and in vivo. In this study, we investigated whether the potent HDAC inhibitor, Trichostatin A, modulates the radiation sensitivity of the human cervical carcinoma cell line Hela under hypoxic conditions. We concluded that TSA could significantly inhibit the proliferation of Hela cells in a dose-and time-dependent manner under normoxic and hypoxic conditions. Hypoxia resulted in the cervical carcinoma Hela cells resistant to TSA. The findings from clonogenic survival assays indicate that incubation with TSA for 24 hours prior to irradiation enhances the radiation sensitivity of Hela cells under hypoxic conditions. More generally, we found Hela cells under hypoxic conditions treated with TSA could significantly down-regulate the expressions of HIF-1alpha and VEGF proteins. Taken together, our results demonstrated that TSA acts as a powerful radiosensitizer in Hela cells under hypoxic conditions probably by down-regulated expression of HIF-1alpha and VEGF proteins.

Elective neck dissection in papillary thyroid carcinoma patients

BACKGROUND

This study was designed to review the diagnostic performance of cervical lymph node metastases for assessment of elective neck dissection in papillary thyroid carcinoma patients and to determine the technique (using Methylene blue dye) that demonstrated the highest success rate with regard to the detection rate and sensitivity.

METHODS

Preoperative 24 h, 1 mL of 1.0% methylene blue was injected into the parenchyma surrounding the primary tumor with ultrasound guidance by a 27-gauge needle. Intra-operative lymph nodes that were stained blue and/or having afferent lymphatic channels stained blue were also considered to be excised. All stained blue nodes were defined by levels, number, site and were sent for frozen and permanent section histologic analysis.

RESULTS

For the 132 patients who underwent methylene blue dye, 1373 lymph nodes were removed. 7 lymph nodes had negative dye results but, in the end, had metastatic lymph nodes. 120 lymph nodes had both negative dye and lymph node results. The number of blue-dye lymph nodes was 1246 and the number of pathology metastatic nodes was 1079, so the pathological diagnose accordance rate was 87.8 percent. The nodal metastases often occur at level VI, IV, III, then in level II, and less in level I and V.

CONCLUSIONS

This method using methylene blue dye is feasible technically and is safe, and the findings correlate with cervical lymph node status. According to the pattern of blue dye lymph nodes and frozen-section histologic analysis, performing elective neck dissection is a reliable, safe surgical procedure for PTC.

Inactivation of the von Hippel-Lindau tumor suppressor leads to selective expression of a human endogenous retrovirus in kidney cancer

A human endogenous retrovirus type E was recently found to be selectively expressed in most renal cell carcinomas (RCC). Importantly, antigens derived from this provirus are immunogenic, stimulating cytotoxic T-cells that kill RCC cells in vitro and in vivo. Here we show HERV-E expression is restricted to the clear cell subtype of RCC (ccRCC) characterized by an inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene with subsequent stabilization of hypoxia-inducible transcription factors HIF-1α and -2α. HERV-E expression in ccRCC linearly correlated with HIF-2α levels and could be silenced in tumor cells by either transfection of normal VHL or siRNA inhibition of HIF-2α. Using chromatin immunoprecipitation, we demonstrated that HIF-2α can serve as transcriptional factor for HERV-E by binding with HIF response elements (HRE) localized in the proviral 5′LTR. Remarkably, the LTR was found to be hypomethylated only in HERV-E-expressing ccRCC while other tumors and normal tissues possessed a hypermethylated LTR preventing proviral expression. Taken altogether, these findings provide the first evidence that inactivation of a tumor suppressor gene can result in aberrant proviral expression in a human tumor and give insights needed for translational research aimed at boosting human immunity against antigenic components of this HERV-E.

Diffuse alveolar hemorrhage in systemic lupus erythematosus: a retrospective study in China

The objective of this study was to determine the clinical features of systemic lupus erythematosus (SLE) patients with diffuse alveolar hemorrhage (DAH). The medical records of 29 patients with DAH among 2133 SLE patients admitted to Peking Union Medical College Hospital from January 2004 to January 2009 were reviewed in this retrospective study. It was found that hypoxemia (100%), dyspnea (90%), cough (79%) and fever (72%), rather than hemoptysis (66%), were the most common symptoms. The most common extrapulmonary presentation was renal involvement (90%). In about 60% of patients nosocomial infection was also present. The mean drop in hemoglobin was 32 ± 10.9 g/l. Mean Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was 17 ± 9. All patients received high-dose corticosteroid therapy and most were also given immunosuppressive agents. Rates of concomitant nosocomial infection and mechanical ventilation in non-survivors were higher than those of survivors (p < 0.05). DAH is a rare and catastrophic event in SLE. DAH can occur at any stage of the disease course; it usually occurs in patients with active SLE, and is frequently complicated by lupus nephritis. Some patients may have no hemoptysis. Early aggressive management with high-dose steroids and cyclophosphamide is advocated.

Localization of phosphorylated SMAD proteins in granulosa cells, oocytes and oviduct of female mice

SMAD signaling is essential for follicular development. The distribution of activated (phosphorylated) SMADs during folliculogenesis has not been described in detail. The present results indicate that oocytes from preantral and antral follicles contain the mRNA for the receptor regulated Smads (-1, -2, -3, -5 and -9), Smad4 (co-SMAD), and Smad6 and Smad7 (inhibitory SMADs). Levels of Smad5, Smad6 and Smad7 mRNA decreased in fully-grown oocytes compared to growing oocytes. Immunostaining for pSMAD1/5/9, pSMAD2 and pSMAD3 was evident in oocytes from primordial, primary, secondary and antral follicles. We also observed substantial staining for pSMADs in intact fully-grown oocytes from antral follicles. In granulosa cells, immunostaining for both pSMAD2/3 and pSMAD1/5/9 was apparent in preantral granulosa cells from primordial to secondary follicles. In antral follicles, immunostaining for pSMADs became more intense in the cumulus cells surrounding the oocyte. Immunostaining for pSMAD2 and pSMAD1/5/9 was also apparent in the epithelium lining of the oviduct. Clearly, oocytes, preantral granulosa cells, cumulus cells and the epithelium of the oviduct are major targets of SMAD-mediated pathways in female reproductive tissues. The finding that pSMAD pathways are active in oocytes raises new questions regarding the role of TGF-beta superfamily members in directly promoting oocyte development. The extent to which defects in pSMAD signaling in oocytes or the oviduct contribute to infertility in humans or animals remains an open question.

A herbicide-resistant ACCase 1781 Setaria mutant shows higher fitness than wild type

It is often alleged that mutations conferring herbicide resistance have a negative impact on plant fitness. A mutant ACCase1781 allele endowing resistance to the sethoxydim herbicide was introgressed from a resistant green foxtail (Setaria viridis (L.) Beauv) population into foxtail millet (S. italica (L.) Beauv.). (1) Better and earlier growth of resistant plants was observed in a greenhouse cabinet. (2) Resistant plants of the advanced BC7 backcross generation showed more vigorous juvenile growth in the field, earlier flowering, more tillers and higher numbers of grains than susceptible plants did, especially when both genotypes were grown in mixture, but their seeds were lighter than susceptible seeds. (3) Field populations originating from segregating hybrids had the expected allele frequencies under normal growth conditions, but showed a genotype shift toward an excess of homozygous resistant plants within 3 years in stressful conditions. Lower seed size, lower germination rate and perhaps unexplored differences in seed longevity and predation could explain how the resistant plants have the same field fitness over the whole life cycle as the susceptible ones although they produce more seeds. More rapid growth kinetics probably accounted for higher fitness of the resistant plants in adverse conditions. The likelihood of a linkage with a beneficial gene is discussed versus the hypothesis of a pleiotropic effect of the ACCase resistance allele. It is suggested that autogamous species like Setaria could not develop a resistant population without the help of a linkage with a gene producing a higher fitness.

Growth inhibition of Microcystis aeruginosa by white-rot fungus Lopharia spadicea

Harmful cyanobacterial blooms cause water deterioration and threaten human health. It is necessary to remove harmful cyanobacteria with useful methods. A bio-treatment may be one of the best ways to do this. A strain of specific white-rot fungus, Lopharia spadicea, with algicidal ability was isolated. Its algicidal ability on algae under various conditions was determined using three main influence factors: initial chlorophyll-a content, initial pH, and algal cell mixture. The result showed that the chlorophyll-a content of Microcystis aeruginosa FACHB-912, Oocystis borgei FACHB-1108, and Microcystis flos-aquae FACHB-1028 decreased from 798+/-13, 756+/-40, and 773+/-24 microg/L to 0 within 39 h. L. spadicea could also remove more than 95% chlorophyll-a when initial chlorophyll-a content increased from 397+/-13 to 2,132+/-4 microg/L. Moreover, the strain has great removal ability under a broad initial pH range of 5.5 to 9.5. The chlorophyll-a content of the three algal strain mixtures decreased from about 672+/-23 microg/L to 0 within 45 h. After superoxide dismutase (SOD) and malondialdehyde (MAD) were assessed in a co-culture of L. spadicea, it was observed that an increase in MAD content was correlated with the decrease in chlorophyll-a content of M. aeruginosa FACHB-912. This result suggested that the algae was not only greatly inhibited but also severely damaged by the fungus.

Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.

Sjögren's syndrome-onset lupus patients have distinctive clinical manifestations and benign prognosis: A case—control study

The objective of this study was to investigate the clinical characteristics and prognosis of Sjögren’s syndrome-onset systemic lupus erythematosus (SS/SLE) patients. Medical charts of 41 consecutive SS/SLE inpatients admitted to Peking Union Medical College Hospital (PUMCH) from February 1998 to February 2008 were systematically reviewed, including demographic data, clinical features, laboratory findings, treatment as well as outcomes. Two hundred and fourteen cases were randomly selected as controls from 2331 SLE-only inpatients treated in PUMCH at the same time period. There were significant differences between SS/SLE and SLE-only patients in the following manifestations (p < 0.05): (1) sex ratio (F/M) (41/0 versus 184/30), age (42.8 ± 41.0 years versus 31.8 ± 31.0 years), disease duration (113.8 ± 84.0 months versus 44.9 ± 18.0 months); (2) clinical features, xerostomia (85.4% versus 6.1%), xerophthalmia (75.6% versus 2.3%), renal tubular acidosis (21.9% versus 0%), interstitial lung disease (12.2% versus 2.8%), facial rash (9.8% versus 46.3%), nephrotic syndrome (7.3% versus 31.3%), central nervous system involvement (4.9% versus 19.6%); (3) laboratory findings, ESR (64.6±75.0mm/h versus 46.5±34.0mm/h), C4 (14.8 ± 12.2 g/dl versus 12.0 ± 10.9 g/dl), IgG elevation (56.4% versus 29.9%) and IgA elevation (38.5% versus 20.4%), RF, anti-SSA and anti-SSB positive rates (70.8% versus 20.3%, 82.9% versus 43.4% and 39.0% versus 7.9%); (4) SLEDAI score (8.0 ± 8.0 versus 10.2 ± 10.0), glucocorticoid treatment (methylprednisolone bolus/1—2 mg kg-1 day-1 prednisone/<1 mg kg-1 day-1 prednisone) (8/26/7 versus 91/102/21), and importantly, rate of death and/or severe irreversible organ failure (2.4% versus 14.9%). SS/SLE patients were followed up for 33.0 ± 34.0 months, 40 cases remained stable at a low dose of corticosteroid. In conclusion, different from SLE-only patients, SS/SLE patients have distinctive clinical manifestations and benign prognosis that require less vigorous treatment with glucocorticoids and/or immunosuppressants. Lupus (2010) 19, 197—200.

Use of short echo time two-dimensional 1H-magnetic resonance spectroscopy in temporal lobe epilepsy with negative magnetic resonance imaging findings

We evaluated short echo time two-dimensional 1H magnetic resonance spectroscopy (2D-1HMRS) with the point-resolved spatial selection (PRESS) protocol in temporal lobe epilepsy (TLE) patients with negative magnetic resonance imaging (MRI) findings and described the characteristics of 2D-(1)HMRS in the epileptic focus. Thirty-eight TLE patients with negative conventional MRI findings and 10 healthy controls were studied by 2D-1HMRS. A 128-channel prolonged video-electroencephalographic (EEG) method was used as the standard for epileptogenic focus localization to evaluate N-acetyl aspartate/(choline + creatine + phosphocreatine) (NAA/[Cho + Cr-PCr]), glutamate + glutamine/creatine (Glx/Cr-PCr) and myo-inositol/Cr-PCr ratios in patients with negative MRI findings. The 2D-1HMRS showed that 32/38 patients and all healthy controls had stable baselines and good signal-to-noise ratios. Compared with the healthy controls, 32 patients showed abnormal NAA/(Cho + Cr-PCr) ratios in the hippocampus and, in 25 of these patients, focus lateralization agreed with the EEG. It is concluded that short echo time 2D-1HMRS with the PRESS protocol can help find abnormalities in lateralization of temporal epilepsy in patients with negative MRI findings.

In vivo selection of human embryonic stem cell-derived cells expressing methotrexate-resistant dihydrofolate reductase

Human embryonic stem cells (hESCs) provide a novel source of hematopoietic and other cell populations suitable for gene therapy applications. Preclinical studies to evaluate engraftment of hESC-derived hematopoietic cells transplanted into immunodeficient mice demonstrate only limited repopulation. Expression of a drug resistance gene, such as Tyr22-dihydrofolate reductase (Tyr22-DHFR), coupled to methotrexate (MTX) chemotherapy has the potential to selectively increase engraftment of gene-modified hESC-derived cells in mouse xenografts. Here, we describe the generation of Tyr22-DHFR – GFP expressing hESCs that maintain pluripotency, produce teratomas and can differentiate into MTXr-hemato-endothelial cells. We demonstrate that MTX administered to nonobese diabetic/severe combined immunodeficient/IL-2Rγc^null (NSG) mice after injection of Tyr22-DHFR-derived cells significantly increases human CD34⁺ and CD45⁺ cell engraftment in the bone marrow (BM) and peripheral blood of transplanted MTX-treated mice. These results demonstrate that MTX treatment supports selective, long-term engraftment of Tyr22-DHFR-cells in vivo, and provides a novel approach for combined human cell and gene therapy.

Prevalence, risk factors and outcome of digital gangrene in 2684 lupus patients

The aim of the study is to assess the clinical characteristics, risk factors and outcome of patients with systemic lupus erythematosus (SLE) complicated with digital gangrene. In all, 2684 consecutive SLE inpatients admitted to Peking Union Medical College Hospital from December 1997 to August 2007 were studied. Demographic data, clinical features, laboratory findings as well as therapeutic regimens were systematically reviewed and a database was established. Cases with digital gangrene were identified and followed up. 1) Eighteen patients with SLE were complicated with digital gangrene, the average age at event was 33.1 ± 11.8 years and the average disease duration was 99.1 ± 60.1 months. 2) Patients with SLE, with long disease duration (≥4 years), Raynaud’s phenomenon and elevated serum C-reactive protein (CRP) were more likely to develop digital gangrene, P = 0.006, 0.001, and 0.031, respectively, OR = 1.03 (95% CI 1.01, 1.04), 35.76 (95% CI 4.67, 273.83) and 9.93 (95% CI 1.23, 80.30), respectively. 3) Fifteen gangrene patients started prednisone ≥1 mg/kg/d, and 18 were treated with cyclophosphamide, although 8 cases failed and ultimately received digital amputation. Prompt corticosteroid treatment (prednisone ≥1 mg/kg/d started within 3 weeks) decreased the hazard of amputation, P = 0.073, HR = 0.13 (95% CI 0.01, 1.21). Long disease duration, Raynaud’s phenomenon and elevated serum CRP were independent predictive factors for SLE to develop digital gangrene. Early and aggressive corticosteroid treatment prevented gangrene from progression and improved prognosis.

Protective factors relating to decreased risks of adolescent suicidal behaviour

BACKGROUND

Suicide has been identified as one of the three leading causes of death in adolescents and young adults. No previous study in China has tested the association between protective factors and urban adolescents' suicidal behaviours. In this study we tested the hypothesis that suicidal behaviours would be associated with multiple protective factors.

METHODS

A stratified random of 9015 students from 100 junior middle schools in Beijing, Hangzhou, Wuhan and Urumqi completed the Chinese version of Global School-Based Student Health Survey.

RESULTS

Overall, 17.4% of students had seriously considered attempting suicide, and 8.1% had made a specific plan to attempt suicide during the 12 months preceding the survey. The students in Wuhan (18.7%) and Urumqi (20.8%) cities were significantly more likely than students in Beijing (14.4%) and Hangzhou (14.4%) to have suicidal ideation (chi2 = 45.9, P < 0.001). Female students were significantly more likely than male students to have suicidal ideation and have made suicide attempts [odds ratio (OR) = 1.4, P < 0.001]. Results indicated that the rates of suicidal ideation and suicide attempts increased with age (OR = 1.44, P < 0.001). Multivariate logistic regression models showed that suicide risk tended to decrease significantly when 'days of missed classes or school without permission were less than one', and when students thought students in their school were kind and helpful most of the time or always', 'parents or guardians checked to see if homework was done most of the time or always', 'parents or guardians understood their problems and worries most of the time or always' and 'parents or guardians really know what they are doing with their free time most of the time or always'.

CONCLUSIONS

Adolescent suicide behaviour should be a serious problem. Measures can be taken to prevent suicide by observing the factors significantly linked to suicidal behaviour. Steps can then be taken to identify adolescents who have serious suicidal ideation so that intervention can be taken to reduce the suicidal rate.

[Establishment of a rabbit model of Acanthamoeba keratitis]

AIM

To establish an animal model of Acanthamoeba keratitis.

METHODS

Six New Zealand white rabbits were each injected intrastromally with Acanthamoeba suspension 3 days after subconjunctival injection with dexamethasone.

RESULTS

All of the 6 rabbits developed keratitis. Acanthamoeba protozoa were identified by the methods of corneal scraping with 10% potassium hydroxide wet mount examined under microscope, corneal protozoa culture and pathological section examination.

CONCLUSION

A rabbit model of Acanthamoeba keratitis was established.

220 SYNERGISTIC EFFECT ON EMBRYO DEVELOPMENT BY INCLUSION OF SUPPLEMENTAL EMBRYOS IN AGAR CHIPS

The main scope of this study was to evaluate the likelihood of a helper effect of agar-embedded cleaved embryos on a low number of free embryos at a similar stage of development within the same culture droplet. Such an improved system could be beneficial within ovum pickup/in vitro embryo production (OPU/IVEP) combined protocols whenever a low number of OPU-derived cleaved embryos are produced per donor. Oocytes were recovered from abattoir ovaries, and after in vitro maturation (IVM) and in vitro fertilization (IVF), presumptive zygotes were deprived of cumulus investment and allocated into culture droplets for 24 h. At 48 h from IVF, 4- to 8-cell cleaved embryos were randomly allocated into a control and a treatment group. Control groups consisted of 1, 3, 5, and 10 embryos, respectively, in 50-μL droplets. Treatment groups consisted of 1, 3, and 5 free embryos with the addition of 9, 7, and 5 embryos, respectively, at a similar stage of development embedded in agar chips, so as to reach a total number of 10 cleaved embryos in each culture droplet. Culture was performed for both the control and treatment groups in SOF medium droplets covered with mineral oil, with the supplementation of essential and nonessential amino acids in a controlled gas atmosphere consisting of 5% CO2, 7% O2, and 88% N2 at 39°C. Final embryo output was checked at Day 7 from IVF. When considering only free embryos, the difference in progression to blastocyst development was highly significant between the control and treatment groups: 1) group 1 v. 1 + 9: 6.6 v. 84.3% (P = 0.00000); 2) group 3 v. 3 + 7: 11.1 v. 41.3% (P = 0.00001); 3) group 5 v. 5 + 5: 24.4 v. 42.2% (P = 0.00001). Rate of blastocyst development in the control group containing 10 cleaved embryos was not significantly different from free cleaved embryos in the 3 + 7 (39.2 v. 41.3%, P = 0.71) and 5 + 5 treatment groups (39.2 v. 42.2%, P = 0.54), but was significantly lower when compared with the 1 + 9 treatment group (39.2 v. 84.3%, P = 0.000). For 1, 3, 5, and 10 control group embryos, the numbers of replicates and total cleaved embryos used (n) were 30 (n = 30), 27, (n = 81), 27 (n = 135), and 39 (n = 390), respectively. For the 1 + 9, 3 + 7, and 5 + 5 treatment group embryos, the numbers of replicates and total cleaved embryos used were 32 (n = 32), 29 (n = 87), and 27 (n = 135), respectively. In conclusion, a beneficial effect of agar-embedded embryos on the development of free embryos within the same culture droplet was shown. A striking improvement in late-stage embryo development was particularly evident when considering the 1 v. 1 + 9 control and treatment groups. These results may foster a different strategic approach in in vitro culture to enhance embryo development from highly valuable donors.

Relationship between protein expression of VEGF-C, MMP-2 and lymph node metastasis in papillary thyroid cancer

Papillary thyroid cancer (PTC) is a common malignancy and has a good prognosis after appropriate treatment. PTC cells spread mainly by lymph node metastasis (LNM), but the mechanism is not well understood. Expression of vascular endothelial growth factor C (VEGF-C) and matrix metalloproteinase 2 (MMP-2) protein was studied immunohistochemically from the archived specimens of 65 PTC patients who initially presented without LNM. In this retrospective study, the frequency of expression differed significantly between thyroid cancer tissue and adjacent normal follicular epithelium (VEGF-C 78.5% and 20.0%, respectively; MMP-2 81.5% and 36.7%, respectively). LNM developed in 35 of the patients during 5 - 15 years of follow-up, by the end of which the frequencies of expression of VEGF-C and MMP-2 protein expression were 91.4% and 94.3%, respectively. Both VEGF-C and MMP-2 protein expression were significantly more frequent in PTC with LNM than without LNM. VEGF-C and MMP-2 protein expression levels were significantly correlated with LNM and it is, therefore, feasible that VEGF-C and MMP-2 may be useful as tumour markers of PTC with cervical LNM.

A novel mouse model of X-linked cardiac hypertrophy

We recovered a novel mouse mutant exhibiting neonatal lethality associated with severe fetal cardiac hypertrophy and with some adult mice dying suddenly with left ventricular hypertrophic cardiomyopathy. Using Doppler echocardiography, we screened surviving adult mice in this mutant line for cardiac hypertrophy. Cardiac dimensions were obtained either from two-dimensional images collected using a novel ECG-gated ultra-high-frequency ultrasound system or by traditional M-mode imaging on a clinical ultrasound system. These analyses identified, among the littermates, two populations of mice: those with apparent cardiac hypertrophy with hypercontractile function characterized by ejection fraction of 75–80%, and normal littermates with ejection fraction of 53–55%. Analysis of the ECG-gated two-dimensional cines indicated that the hypertrophy was of the nonobstructive type. Further analysis of heart-to-body weight ratio confirmed the ultrasound diagnosis of left ventricular hypertrophic cardiomyopathy. Histopathology showed increased ventricular wall thickness, enlarged myocyte size, and mild myofiber disarray. Ultrastructural analysis by electron microscopy revealed mitochondria hyperproliferation and dilated sarcoplasmic reticulum. Genome scanning using microsatellite DNA markers mapped the mutation to the X chromosome. DNA sequencing showed no mutations in the coding regions of several candidate genes on the X chromosome, including several known to be associated with left ventricular hypertrophic cardiomyopathy. These findings suggest that this mouse line may harbor a mutation in a novel gene causing X-linked cardiomyopathy.

Receptor-mediated internalization of chelator-PNA-peptide hybridization probes for radioimaging or magnetic resonance imaging of oncogene mRNAs in tumours

Early external detection of cancer gene activity might enable early treatment of cancer and might reduce cancer mortality. We hypothesized that oncogene mRNA overexpressed at thousands of copies per malignant cell in a zone of transformed cells could be imaged externally by scintigraphic imaging, PET (positron emission tomography) or MRI (magnetic resonance imaging) with PNA (peptide nucleic acid) hybridization probes that include chelators for metal cations and a cyclized peptide analogue of IGF-1 (insulin-like growth factor 1), D(Cys-Ser-Lys-Cys), to mediate internalization by IGF1R (IGF-1 receptor) overexpressed on cancer cells. We observed that human MCF7 breast cancer cells that overexpress IGF1R efficiently internalized fluorescein-chelator-PNA-D(Cys-Ser-Lys-Cys) to the cytoplasm, but not with D(Cys-Ala-Ala-Cys). Scintigraphic imaging of MCF7 xenografts in immunocompromised mice revealed that CCND1 and MYC [(99m)Tc]chelator-PNA-D(Cys-Ser-Lys-Cys) probes yielded xenograft. PET imaging with [(64)Cu]chelator-PNA-D(Cys-Ser-Lys-Cys) yielded stronger signals. Scintigraphic imaging of human AsPC1 pancreas cancer xenografts with [(99m)Tc]chelator-KRAS PNA-D(Cys-Ser-Lys-Cys) yielded strong xenograft signals. Stronger xenograft image intensities were obtained by PET imaging of [(64)Cu]chelator-KRAS PNA-D(Cys-Ser-Lys-Cys). MRI required extension of chelator-polydiamidopropanoate dendrimers from the N-termini of the PNA probes to increase the number of contrast paramagnetic gadolinium (III) cations per probe. These results provide a basis for detection of oncogene activity in tissues from outside the body by hybridization with metal-chelator-PNA-peptides that are selectively internalized by cancer cells.