Vibrational Excitations and Low Energy Electronic Structure of Epoxide-decorated Graphene

We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.

A sensitive and specific nanoparticle-assisted PCR assay for rapid detection of porcine parvovirus

A novel nanoparticle-assisted polymerase chain reaction (nanoPCR) assay to detect porcine parvovirus (PPV) is described here. Primers for this assay were designed based on the conserved region of the nonstructural protein 1 (NS1) gene of PPV, which encodes one of the nonstructural proteins. The sensitivity of the PPV nanoPCR assay was measured by using diluted recombinant plasmids in which the PPV NS1 gene had been inserted. The detection limit was 5.6 × 10(1) copies μl(-1) for the PPV nanoPCR assay vs 5.6 × 10(3) copies μl(-1) for conventional PCR assay. The results showed that the sensitivity of PPV nanoPCR assay was 100 times higher than that of conventional PCR assay. The PPV nanoPCR assay produced 142-bp product as expected when amplifying PPV DNA, while produced nothing when amplifying the DNA or cDNA of the following viruses: swine encephalomyocarditis virus, classical swine fever virus, porcine pseudorabies virus, porcine reproductive and respiratory syndrome virus, porcine teschovirus and porcine circovirus type II. PPV was detected in 108 of 109 clinical swine samples from Heilongjiang, Jilin and Henan provinces using the nanoPCR assay, and the results were confirmed by sequencing.

SIGNIFICANCE AND IMPACT OF THE STUDY

Nanoparticle-assisted polymerase chain reaction (nanoPCR) assay is an improved PCR. NanoPCR is highly sensitive and specific because the nanofluids formed in the nanobuffer have high thermal conductivity, which reduces the time required to reach the target temperature. It is more sensitive than conventional PCR, and it could detect the cases earlier than conventional PCR. This report describes the first application of the highly efficient nanoPCR technology for the detection of porcine parvovirus (PPV). The PPV nanoPCR assay will be useful for the detection and study of PPV and will also be applicable to improve the detection of other viruses.

DNA double-strand break repair is activated in carotid artery restenosis

Carotid stenosis is a narrowing or constriction of the inner surface of the carotid artery, usually caused by atherosclerosis. In the past decades, carotid angioplasty and stenting (CAS) has been developed into a credible option for the patients with carotid stenosis. However, restenosis remains a severe and unsolved issue after CAS treatment. Currently, the molecular mechanisms involved in the restenosis are still largely unclear. In this study, we found that the double-strand DNA breaks (DSBs) were induced by oxidative stress in the human carotid artery with restenosis by examining the level of γH2AX in the artery tissues. We further analyzed the activation of DNA damage repair pathways in the carotid restenosis. Our results suggest that non-homologues end joining (NHEJ), but not homologous recombination (HR), is mainly activated in the artery tissues with restenosis. Our results may provide clues to develop a new therapeutic strategy for carotid artery restenosis following CAS treatment.

[Effect of substrate temperature on structure and photoluminescence of ZnMgO films]

ZnMgO films were deposited on quartz glass substrates by the ultrasonic spray pyrolysis at different substrate temperatures (450-550 degrees C). The structural, surface morphological and optical properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) spectroscopy. The results demonstrate that the substrate temperature has important effect on structural and optical characteristics. All the films have hexagonal wurtzite polycrystalline structures and the c-axis preferential orientation has an optimum temperature of 530 degrees C. The sample prepared at this temperature owns uniform grain size, smooth surface morphology and better crystalline quality. The width of deep-level emission decreases and the near band edge (NBE) ultraviolet emission peak appears with the increase in temperature by the PL spectrum. When the temperature arrives to 530 degrees C, a distinct NBE emission peak can be observed at 374. 5 nm, while the deep level emission is almost undetectable.

Multi-therapeutic effects of human adipose-derived mesenchymal stem cells on radiation-induced intestinal injury

Radiation-induced intestinal injuries (RIII) commonly occur in patients who suffer from pelvic or abdominal cancer. However, current management of these injuries is ineffective. Recently, mesenchymal stem cells (MSCs) have been extensively used in regenerative medicine and have achieved a high level of efficacy. In the present study, we hypothesised that human adipose-derived mesenchymal stem cells (hAd-MSCs) could be used as potential tools to heal RIII. We observed that adult Sprague-Dawley rats that received whole-abdominal irradiation benefitted from hAd-MSC injection. hAd-MSCs had RIII-healing effects, including anti-inflammation, neovascularisation and maintenance of epithelium homeostasis, as indicated by elevated serum IL-10, upregulation of vascular endothelial growth factor, basic fibroblast growth factor and epidermal growth factor in irradiated intestine, mobilisation of CD31-positive haematopoietic stem cells or haematopoietic progenitor cells, and the prolonged presence of Bmi1-positive cells within crypts. Consequently, after hAd-MSC treatment, irradiated rats survived longer than non-treated animals. These results suggest that hAd-MSCs have therapeutic potential for RIII management.

A novel allele, HLA-A*03:01:09, identified by sequence-based typing in a Chinese individual

We describe the identification of a novel allele HLA-A*03:01:09 in a Chinese individual.

From selenium- to tellurium-based glass optical fibers for infrared spectroscopies

Chalcogenide glasses are based on sulfur, selenium and tellurium elements, and have been studied for several decades regarding different applications. Among them, selenide glasses exhibit excellent infrared transmission in the 1 to 15 µm region. Due to their good thermo-mechanical properties, these glasses could be easily shaped into optical devices such as lenses and optical fibers. During the past decade of research, selenide glass fibers have been proved to be suitable for infrared sensing in an original spectroscopic method named Fiber Evanescent Wave Spectroscopy (FEWS). FEWS has provided very nice and promising results, for example for medical diagnosis. Then, some sophisticated fibers, also based on selenide glasses, were developed: rare-earth doped fibers and microstructured fibers. In parallel, the study of telluride glasses, which can have transmission up to 28 µm due to its atom heaviness, has been intensified thanks to the DARWIN mission led by the European Space Agency (ESA). The development of telluride glass fiber enables a successful observation of CO₂ absorption band located around 15 µm. In this paper we review recent results obtained in the Glass and Ceramics Laboratory at Rennes on the development of selenide to telluride glass optical fibers, and their use for spectroscopy from the mid to the far infrared ranges.

A novel HLA-B allele, B*07:55, identified by sequence-based typing

The novel allele differs from HLA-B*07:02:01 by a single nucleotide substitution at position 538 in exon 3.

Identification of a novel HLA-A allele, A*24:128 in a Chinese individual

The novel HLA-A*24:128 shows one nucleotide change from HLA-A*24:02:01:01 in exon 2 at position 155 from A to G.

A novel HLA-B allele, B*13:18, identified by sequence-based typing

The B*13:18 allele differs from the most closely matching allele B*13:02:01 by one nucleotide substitution in exon 3, at position 539.

Bioinformatics analysis of two microarray gene-expression data sets to select lung adenocarcinoma marker genes

BACKGROUND

Lung adenocarcinoma (LAC) is the most frequent histologic type of lung cancer and rates of adenocarcinoma are increasing in most countries. Recently, several molecular markers have been identified to predict LAC. However, more prognostic makers and the underlying role of those makers are still imperative.

AIM

In this study, our objective was to identify a set of discriminating genes that can be used for characterization and prediction of response to LAC.

MATERIALS AND METHODS

Using the bioinformatics analysis method, we merged two LAC datasets-GSE2514 and GSE7670 to find novel target genes and pathways to explain the pathogenicity.

RESULTS

The results showed that EDNRB (endothelin receptor type B), ADRB2 (beta-adrenergic receptor), S1PR1 (sphingosine-1-phosphate receptor 1), P2RY14 (PsY purinoceptor 14), LEPR (leptin-receptor), GHR (growth hormone receptor), PPM1D (protein phosphatase-1D), and GADD45B (growth arrest and DNA-damage-inducible, beta) have high degrees in response to LAC. Additionally, EDNRB, ADRB2, S1PR1, P2RY14, LEPR, and GHR may be involved in LAC through Neuroactive ligand-receptor interaction, but PPM1D and GADD45B may be through p53 signaling pathway. Some of our prediction had been demonstrated by previous reports, such as ADRB2, S1PR1, GHR, PPM1D, and GADD45B. Therefore, we hope our study could lay a basis for further study of other target genes, such as EDNRB, P2RY14, and LEPR.

CONCLUSIONS

It is effective to identify potential molecular marker for LAC and predict their underlying functions by bioinformatics analysis and graph clustering method. However, further experiments are still indispensable to confirm our conclusion.

Cigarette smoking extract causes hypermethylation and inactivation of WWOX gene in T-24 human bladder cancer cells

Genomic, epigenetic and expression alterations of WW domain containing oxidoreductase (WWOX) have been implicated in multiple tumor types. The current study was designed to examine the expression of WWOX in tumor tissues of human bladder transitional cell carcinoma (BTCC) and the influence of cigarette smoke extract (CSE) on WWOX expression and methylation status in T-24 bladder cancer cells. WWOX protein expression was evaluated by immunohistochemistry staining in a series of tumor samples from 78 patients with BTCC and 26 normal bladder tissues. The expression level and methylation status of WWOX in CSE-treated cells were examined by using quantitative Real-Time RT-PCR and methylation specific PCR, respectively. The expression levels of DNA methyltransferases (DNMTs) 1, 3A and 3B were also detected. We found that WWOX expression was absent or reduced in 79.5% (62/78) of BTCC tissues, but only in 19.2% (5/26) of normal bladder tissues. Loss of WWOX expression was correlated with tumor grade (P=0.019) and cigarette smoking (P=0.031), but was not associated with age, gender, tumor size and tumor number. Hypermethylation of WWOX promoter and exon 1 was specifically induced by CSE with a kinetics concurrent to the suppression of WWOX mRNA in T-24 cells. Furthermore, CSE treatment induced a significant time-dependent increase in the level of DNMT1, but has no effects on DNMT3A and DNMT3B. Taken together, these novel findings suggest that hypermethylation of WWOX induced by cigarette smoking may represent one underlying mechanism for the loss expression of WWOX in bladder cancer.

[Fluorescence fingerprint transformation of municipal wastewater caused by aerobic treatment]

The conventional parameters such as COD and BOD only could represent information about total organic content. Fluorescence spectrum can display organic composition and it is unique for each sample, so it is referred as "fluorescence fingerprint". In the present study transformation of excitation-emission matrix of municipal wastewater with sewage as major components after aerobic treatment was investigated and then the zones of biodegradable and non-biodegradable organic matters were figured out: the fluorescence at excitation wavelength/emission wavelength of about 280/340 nm and 225/240 nm derived from biodegradable organics and those of the zone of excitation wavelength above 300 nm and the zone of excitation wavelength below 300 nm and emission wavelength above 400 nm were mainly related with non-biodegradable organics. The above-mentioned results indicated that fluorescence fingerprint could be used to evaluate the performance and instruct design and operation of aerobic systems.

Peer relationships and suicide ideation and attempts among Chinese adolescents

BACKGROUND

Suicide is a global health concern. Therefore, studying suicide behaviour and identifying the early roots of suicide are critical. To address these issues, the present study examined (i) the association between peer relationships and suicide ideation and attempts among Chinese adolescents; and (ii) whether such associations were moderated or mediated by feeling of loneliness. We hypothesized that problems in peer relationships were positively associated with suicide ideation and attempts, and that feeling of loneliness would moderate and mediate such associations.

METHODS

The sample included 8778 Chinese adolescents from a large survey. Measures of peer relationships, suicide ideation and attempts, and feeling of loneliness were obtained through adolescents' self-reports.

RESULTS

Results from multivariate logistic regressions suggested that specific problems in peer relationships, such as lack of peer association and being victimized by bullying, were significantly related to suicide ideation and attempts. In addition, the moderating effects of feeling of loneliness on the association between peer relationships and suicide ideation and attempts were found. Finally, some gender effects were also found.

CONCLUSIONS

The present study provided strong evidence that suicide ideation and attempts were serious problems among adolescents in China, to which peer relationships played an important role. Further, feeling of loneliness acted as a moderator affecting the association between peer relationships and suicide ideation and attempts. Finally, there were some gender differences that have important implications.

[Fluorescence properties of urban water bodies of Beijing]

"Fluorescence fingerprint" of water body based on fluorescence excitation-emission matrix has been a novel and valuable method to exhibit the organics details. In the present study, the fluorescence matrixes of urban water bodies of Beijing were investigated. The experimental results showed that these matrixes could be divided into 3 groups: Type I owned two fluorescence centers, locating at lambda(ex)/lambda(em) = 275-280/340 and 225-230/340 nm respectively, and was the predominant group; fluorescence centers of Type II located at lambda(ex)/lambda(em) = 280/345-365 and 245/380 nm; Type II had four fluorescence centers around 275/305, 275/340, 225/305 and 225/340 nm. The fingerprints indicated that these water bodies had been disturbed by human activities. Type I and Type III were transitional fingerprints between undisturbed water body and sewage wastewater and Type III was closer to sewage wastewater. Type II closely originated from reclaimed water of municipal wastewater treatment plant. These three types were main types of urban water bodies where domestic pollution was dominating. The fluorescence fingerprints clearly displayed the ubiquitous impacts of human activities and the resulting potential risk. Fluorescence fingerprint could display pollution information and serve as a possible diagnosis tool of pollution source.

A 5-week study of the pharmacokinetics and pharmacodynamics of LY2189265, a novel, long-acting glucagon-like peptide-1 analogue, in patients with type 2 diabetes

AIM

To investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of LY2189265 (LY), a novel, long-acting glucagen-like peptide-1 analogue, administered once weekly to subjects with type 2 diabetes.

METHODS

This was a placebo-controlled, parallel-group, subject- and investigator-blind study of LY in subjects (N = 43) with type 2 diabetes mellitus controlled with diet and exercise alone or with a single oral antidiabetic medication. Subjects taking metformin or thiazolidinediones continued on their therapy. Subjects receiving sulfonylurea, acarbose, repaglinide or nateglinide were switched to metformin prior to enrollment. Subjects received five once-weekly doses of 0.05, 0.3, 1, 3, 5 or 8 mg. Effects on glucose, insulin and C-peptide concentrations were determined during fasting and following standard test meals. The pharmacokinetics of LY and its effects on HBA1c, glucagon, body weight, gastric emptying and safety parameters were assessed.

RESULTS

Once-weekly administration of LY significantly reduced (p < 0.01) fasting plasma glucose, 2-h post-test meal postprandial glucose and area under the curve (AUC) of glucose after test meals at doses ≥1 mg. These effects were seen after the first dose and were sustained through the weekly dosing cycle. Most doses produced statistically significant increases in insulin and C-peptide AUC when normalized for glucose AUC. Statistically significant reductions in HBA1c were observed for all dose groups except 0.3 mg. The most commonly reported adverse effects (AEs) were nausea (35 events), headache (20 events), vomiting (18 events) and diarrhoea (8 events).

CONCLUSIONS

LY showed improvement in fasting and postprandial glycaemic parameters when administered once weekly in subjects with type 2 diabetes. The pharmacokinetics and safety profiles also support further investigation of this novel agent.

MTBP plays a crucial role in mitotic progression and chromosome segregation

Murine double minute 2 (MDM2) binding protein (MTBP) has been implicated in tumor cell proliferation, but the underlying mechanisms remain unclear. The results of MTBP expression analysis during cell cycle progression demonstrated that MTBP protein was rapidly degraded during mitosis. Immunofluorescence studies revealed that a portion of MTBP was localized at the kinetochores during prometaphase. MTBP overexpression delayed mitotic progression from nuclear envelope breakdown (NEB) to anaphase onset and induced abnormal chromosome segregation such as lagging chromosomes, chromosome bridges, and multipolar chromosome segregation. Conversely, MTBP downmodulation caused an abbreviated metaphase and insufficient mitotic arrest, resulting in abnormal chromosome segregation, aneuploidy, decreased cell proliferation, senescence, and cell death, similar to that of Mad2 (mitotic arrest-deficient 2) downmodulation. Furthermore, MTBP downmodulation inhibited the accumulation of Mad1 and Mad2, but not BubR1 (budding uninhibited by benzimidazoles related 1), on the kinetochores, whereas MTBP overexpression inhibited the release of Mad2 from the metaphase kinetochores. These results may imply that MTBP has an important role in recruiting and/or retaining the Mad1/Mad2 complex at the kinetochores during prometaphase, but its degradation is required for silencing the mitotic checkpoint. Together, this study indicates that MTBP has a crucial role in proper mitotic progression and faithful chromosome segregation, providing new insights into regulation of the mitotic checkpoint.

Basic public health services delivered in an urban community: a qualitative study

OBJECTIVES

To understand the advancements in and barriers to the implementation of measures to improve basic public health services in an urban Chinese community.

STUDY DESIGN

A qualitative study based on semi-structured interviews. Interviews were audio-taped, transcribed and analysed using thematic content analysis.

METHODS

In-depth interviews were undertaken with the directors of the management centres for community health services in 15 of the 18 districts in Beijing from December 2008 to February 2009. Content analysis of the data was completed in May 2009.

RESULTS

Fifteen types of free basic public health services had been delivered in Beijing. Some were supplied at a low level. An average of £2.38 per person per year was provided for inhabitants since 2008, but demand for funding far exceeded monies available. Teams consisting of general practitioners, community nurses and public health specialists delivered these services. The number of practitioners and their low levels of skill were insufficient to provide adequate services for community residents. Respondents gave recommendations of how to resolve the above problems.

CONCLUSIONS

In order to improve the delivery of basic public health services, it is necessary for Beijing Municipal Government to supply clear and detailed protocols, increase funding and increase the number of skilled practitioners in the community health services.

Identification of site(s) of insulin nitration by peroxynitrite and characterization of its structural change

Insulin nitration mediated by peroxynitrite (ONOO(-)) has been implicated in diabetes and diabetic cardiovascular complications. In this study, we identified the nitration sites of porcine insulin by infusion of ONOO(-) and quantified its secondary structural change. Insulin was cleaved with V8 protease to six peptides (four of them contained each tyrosine residue), then analyzed by HPLC-MS and further confirmed the nitration sites by HPLC-MS/MS. At low accumulated doses of peroxynitrite, the main products were two different mono-nitrated insulin species at Tyr-A19 and Tyr-B26 with Tyr-A19 being predominant as shown by peptide mapping. Also, the content of alpha-helix structure of insulin reduced to 22.9 % and random-coil structure increased to 30.2 % (compare with native insulin of 41.7 % and 13.7 %, respectively) as determined by FTIR spectra.

Novel immunocontraceptive targets in mammals: uterine secretions and the conceptus; a marsupial approach

We report the first immunocontraceptive trial in mammals using a uterine-secreted protein, the marsupial shell coat protein 4 (CP4). The marsupial shell coat, which surrounds the conceptus for 60–80% of gestation, is secreted by the uterine epithelium. Following immunization against glutathione S-transferase (GST)-CP4, the fertility of female common brushtail possums (n=6) was significantly reduced (P=0.000), and this reduction in fertility was positively correlated with the maximum GST-CP4 humoral immune response (P=0.025). Ultrastructural examination of the reproductive tract indicated that the cell-mediated immune response against GST-CP4 targeted the shell coat, the shell-free conceptus and the uterine glandular epithelium, thus preventing normal conceptus development and uterine secretion of shell coat proteins and nutrients. These results show that uterine-secreted proteins are promising immunocontraceptive targets, especially in pest mammal species, e.g. possum, rabbit and horse, that have uterine-secreted additions to embryonic coats, or that have late implantation requiring uterine nutrient provisioning from secretions.

Vesicle-associated protein 1: a novel ovarian immunocontraceptive target in the common brushtail possum, Trichosurus vulpecula

Ovarian-based immunological research is currently restricted to proteins of the zona pellucida. This study examined the immunocontraceptive potential of a novel vesicle-associated protein, VAP1, previously isolated from the vesicle-rich hemisphere of the brushtail possum oocyte. Seven female possums were immunized against recombinant glutathione S-transferase-VAP1 fusion protein. Control animals (n=3) received antigen-free vaccinations. Following immunization, regular blood sampling determined the level and duration of immune response. Animals were monitored daily, pre- and post-immunization, to determine estrous cycling activity and the percentage of reproductive cycles yielding viable young. The reproductive tracts and somatic organs of VAP1-immunized (n=7), control-immunized (n=3) and non-immunized (n=5) animals were collected and examined by histology and transmission electron microscopy. VAP1 immunization caused a strong and sustained immune response. Elevated levels of VAP1 antibody binding were detected in sera following initial injections, and immune titers rose as boosters were administered. Immunization had no adverse effect upon animal behavior or body condition. Immunized females demonstrated no major change in annual estrous cycling activity; however, the percentage of reproductive cycles resulting in pouch young decreased significantly (P<0.05) by 40%. Histological and ultrastructural analyses revealed an abundance of lipid-like degradation bodies within the ooplasm of developing oocytes and the cytoplasm of failing uterine zygotes. Active macrophage invasion of enlarged endometrial glands was observed in the uteri of two females. Reproductive tract changes are discussed in relation to observed fertility decline. The results of this study indicate that VAP1 has exciting potential as an immunocontraceptive target for possum control in New Zealand.

In vitro assessment of antimicrobial activity of carvacrol, thymol and cinnamaldehyde towards Salmonella serotype Typhimurium DT104: effects of pig diets and emulsification in hydrocolloids

AIMS

To determine the effect of pig diets in vitro on the antimicrobial activity of carvacrol, thymol and cinnamaldehyde, and to identify an emulsifier/stabilizer that can stabilize the essential oil (EO) components in aqueous solution and retain their antimicrobial activity in the presence of the diets.

METHODS AND RESULTS

Emulsification of essential oil components with hydrocolloid solution was achieved by blending with a Polytron. Antimicrobial activity was measured through in vitro assays to determine the inhibition of bacterial growth by measuring the optical density at 600 nm or plating on nutrition agar after incubation of the mixtures of an EO component with the culture of Salmonella serotype Typhimurium DT104 in the presence or absence of pig diets. The results generated through the in vitro assays indicated that pig diets were able to abolish the antimicrobial activity of EOs. Xanthan, fenugreek and yellow mustard gums were the best in forming stable emulsions of five different EO components among ten different plant polysaccharides and surfactants examined. Emulsification of all the EO components in the fenugreek gum solution did not alter their antimicrobial activity. However, the antimicrobial activity of geraniol was significantly reduced when emulsified with other polysaccharides and surfactants. Both fenugreek and xanthan gum solutions were unable to protect the antimicrobial activity of carvacrol and thymol when mixed with the diets. Although cinnamaldehyde required no emulsification, but a high concentration (equivalent to at least three times of minimum bactericidal concentration for cinnamon oil) to inhibit Salmonella growth significantly in the presence of the diets, emulsification in fenugreek gum appeared to be essential for cinnamaldehyde solution to retain its antimicrobial activity during storage.

CONCLUSIONS

The diets for newly weaned pigs were a significant factor limiting the antimicrobial activity of EOs and their components. Cinnamaldehyde required a high concentration to retain its antimicrobial activity in the diets, in addition to its requirement for emulsification to stabilize its activity during the storage.

SIGNIFICANCE AND IMPACT OF THE STUDY

The assay with the diets used in this study for measuring the antimicrobial activity can be used in vitro for rapid and effective screening of potential antimicrobials for swine production. This study has identified polysaccharides that are able to stabilize EO component solutions. It has also identified cinnamaldehyde for further in vivo studies that may have potential in future application in controlling Salmonella and possibly other enteric pathogens in swine production.

MicroRNAs that underlie response to salvage chemotherapy in ovarian cancer

10542

Background: MicroRNAs (miRNAs) are non-protein coding, endogenous, small RNAs that can bind complementary mRNA to modulate gene expression and protein translation. Recent studies indicate that miRNAs may be mechanistically involved in ovarian cancer chemosensitivity and may play an important role in the development of chemoresistance. The objective of the current study was to explore the role of miRNAs in the response of platinum-resistant recurrent or persistent ovarian cancer to salvage chemotherapy. Methods: MicroRNA was extracted from 16 ovarian cancer cell lines. All samples were hybridized to a miRNA array that contained Ambion and Invitrogen probe sets. In parallel, the 16 ovarian cancer cell lines were treated with Doxorubicin, Topotecan, Paclitaxel, Docetaxel, and Gemcitabine, and their response to treatment evaluated using proliferation assays. Logistic regression analysis was used to identify miRNAs associated with responsiveness to individual chemotherapeutic agents. Results: Linear regression analysis identified a total of 39 miRNAs significantly associated with salvage chemotherapy responsiveness. Sixteen miRNAs were associated with response to Doxorubicin, 18 associated with response to Topotecan, 2 associated with response to Docetaxel, 9 associated with response to Paclitaxel, and 11 associated with response to Gemcitabine (p<0.05). Ten miRNAs were associated with more than one chemotherapy (miR-126, miR-199a, miR-202 [Doxorubicin, Topotecan, Gemcitabine], miR-26a, miR-320 [Doxorubicin, Topotecan], miR-181b [Doxorubicin, Topotecan, Paclitaxel], 181a [Topotecan, Gemcitabine, Adriamycin, Paclitaxel], miR-99b [Doxorubicin, Paclitaxel, Docetaxel], miR-31 [Docetaxel, Paclitaxel], miR-339 [Doxorubicin, Gemcitabine]). Conclusion: We have identified miRNAs that may influence ovarian cancer responsiveness to salvage chemotherapy. Ten of the miRNAs were associated with chemosensitivity to more than one drug. These miRNAs may regulate common determinants of chemoresistance and may also serve as novel therapeutic targets for patients with chemoresistant ovarian cancer. Further studies are warranted to validate these results.

No significant financial relationships to disclose.

Hepatic pre-sinusoidal vessels contract in anaphylactic hypotension in rabbits

AIM

The purpose of this study was to determine whether anaphylactic hypotension in rabbits is accompanied by hepatic venoconstriction, and the effects of anaphylaxis on hepatic segmental vascular resistances and liver weight in isolated perfused rabbit livers.

METHODS

The rabbits were sensitized by subcutaneous injection of antigen of 2.5 mg ovalbumin with complete Freund's adjuvant three times at 1 week interval. One week after sensitization, anaphylaxis was induced by an injection of 2.5 mg ovalbumin into the jugular vein of pentobarbital anaesthetized rabbits or the perfusate of rabbit livers perfused via the portal vein at a constant flow. Using the double occlusion technique to estimate the hepatic sinusoidal pressure, pre- (R(pre)) and post-sinusoidal (R(post)) resistances were calculated for the isolated perfused livers.

RESULTS

An antigen injection into the sensitized rabbits caused not only a decrease in systemic arterial pressure from 79 +/- 2 to 40 +/- 4 mmHg, but also an increase in portal venous pressure (P(pv)) from 9.5 +/- 2.2 to 24.1 +/- 3.9 cmH(2)O. Portal hypertension persisted for 8 min after the antigen injection. An injection of antigen into the perfusate caused a marked increase in P(pv) from 5.4 +/- 0.1 to 28.6 +/- 2.4 cmH(2)O at 6 min, but only a slight increase in double occlusion pressure from 2.2 +/- 0.2 to 3.8 +/- 0.2 cmH(2)O, resulting in a selective increase in R(pret) rather than R(post). Concomitant with the hepatic pre-sinusoidal constriction, liver weight loss occurred.

CONCLUSION

Anaphylactic hypotension in rabbits is accompanied by hepatic venoconstriction which is characterized by pre-sinusoidal contraction.

Islet-1 expression and its colocalization with luteinising hormone, thyroid-stimulating hormone and oestrogen receptor alpha in the developing pituitary gland of the sheep foetus

Islet-1 has been reported to be involved in pituitary development in the early stages of mouse embryogenesis. Oestrogen receptor (ER) and its expression may be involved in regulating pituitary development and its hormone-secreting function. Islet-1 expression and its correlations to ER in the developing pituitary gland are unknown. We therefore determined the pituitary cell specific expression of Islet-1 and its colocalization with ER alpha (ERalpha) in sheep foetus by immunohistochemistry. The results demonstrated that Islet-1-immunoreactive (ir) cells were distributed throughout the pituitary gland from day 60 of gestation until birth. The Islet-1-ir cell number was significant higher at day 90 and 120 of gestation compared to that at day 60 and at birth. All of the ERalpha-ir cells were colocalized with Islet-1 at day 60 of gestation, although a few ERalpha-ir cells were negative for Islet-1 in the later stage of gestation. The dominant cell type expressing Islet-1 is the gonadotroph, although small proportions of thyrotrophs and lactotrophs also express Islet-1. The proportion of luteinising hormone-ir gonadotrophs possessing Islet-1 kept rising from day 60 to day 120 of gestation and persisted until birth. The proportion of thyroid-stimulating hormone-ir cells expressing Islet-1 was at a high level from day 60-120 of the gestation and significantly declined at birth. The percentage of prolactin (PRL)-ir cells expressing Islet-1 was about 20% at day 60 of gestation. Very few PRL-ir cells contained Islet-1 in later stages of gestation. These data suggest that the development and functional establishment of pituitary gonadotrophs, thyrotrophs and lactotrophs might be regulated by the expressions of Islet-1 and ERalpha and by their interactions, although any mechanisms need to be elucidated further.

Role of interfacial effects in carbon nanotube/epoxy nanocomposite behavior

The interfacial effects are critical to understand the nanocomposite behavior based on polymer matrices. These effects are dependent upon the morphology of carbon nanotubes, the type of used polymer and the processing technique. Indeed, we show that the different parameters, as the eventual surfactant use, the ultrasonic treatment and shear mixing have to be carefully examined, in particular, for nanotube dispersion and their possible alignment. A series of multiwalled nanotubes (MWNT) have been mixed with a regular epoxy resin under a controlled way to prepare nanocomposites. The influence of nanotube content is examined through helium bulk density, glass transition temperature of the matrix and direct current electrical conductivity measurements. These results, including the value of the percolation threshold, are analyzed in relationship with the mesostructural organization of these nanotubes, which is observed by standard and conductive probe atomic force microscopy (AFM) measurements. The wrapping effect of the organic matrix along the nanotubes is evidenced and analyzed to get a better understanding of the final composite characteristics, in particular, for eventually reinforcing the matrix without covalent bonding.

Rapid sample preparation method for PCR-based detection of Escherichia coli O157:H7 in ground beef

AIM

To develop an improved, rapid and sensitive sample preparation method for PCR-based detection of Escherichia coli O157:H7 in ground beef.

METHODS AND RESULTS

Fresh ground beef samples were experimentally inoculated with varying concentrations of E. coli O157:H7. PCR inhibitors were removed and bacterial cells were concentrated by filtration and centrifugation, and lysed using enzymatic digestion and successive freeze/thaw cycles. DNA was purified and concentrated via phenol/chloroform extraction and the Shiga toxin 1 gene (stx1) was amplified using PCR to evaluate the sample preparation method. Without prior enrichment of cells in broth media, the detection limit was 103 CFU g-1 beef. When a 6 h enrichment step was incorporated, the detection limit was 1 CFU g-1 beef. The total time required from beginning to end of the procedure was 12 h.

CONCLUSIONS

The sample preparation method developed here enabled substantially improved sensitivity in the PCR-based detection of E. coli O157:H7 in ground beef, as compared to previous reports.

SIGNIFICANCE AND IMPACT OF THE STUDY

Superb sensitivity, coupled with quick turn-around time, relative ease of use and cost-effectiveness, makes this a useful method for detecting E. coli O157:H7 in ground beef.

Sexual development and the effects of active immunization against GnRH in Chinese Tanyang ram lambs

Tanyang is one of the most important sheep breeds in the northwest of China. However, there is no detailed data on sexual development and timing of puberty/sexual maturity of this breed. This experiment was designed to study the relationships between growth rate and sexual development by measuring body weight, testis diameter, and plasma testosterone concentrations, and observing sexual behavior through puberty from 3 to 8 months old of entire Tanyang ram lambs. At same time, to assess the potential efficacy and welfare benefits of non-surgical castration, the effect of active immunization against gonadotrophin-releasing hormone (GnRH) on sexual development and growth rate on ram lambs was evaluated, and compared with surgically castrated and entire lambs. The results showed that body weight increased at a constant rate from 3 to 8 months old of age. Testis diameter increased rapidly between 3 and 5 months, followed by a period of slow growth. Plasma testosterone concentrations increased sharply from 3 to 6 months of age (P<0.05), after which there were no significant changes from 6 to 8 months of age. Sexual behavior started from 5 months of age. After ram lambs were immunized against GnRH at 3 months of age, there was no increase in testis diameter in the first 4 months after immunization. Plasma testosterone concentrations remained at similar levels to surgically castrated lambs until 6 months of age, and the onset of sexual behavior was delayed, compared with entire ram lambs. GnRH immunization and surgical castration had no significant effect on the body weight by the end of this experiment. These results suggest that 4-5 months of age is a critical period for pubertal changes and testosterone plays an important role in the initiation of puberty and sexual maturity of Tanyang ram lambs in China. In addition, a single shot GnRH immunization at 3 months, acting as an alternative to surgical castration, is a practical method for Chinese Tanyang ram lambs, and provides animal welfare benefits.

Predicting toxicity of benzene derivatives by molecular hologram derived quantitative structure-activity relationships (QSARS)

Holographic quantitative structure-activity relationship (HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encodes the frequency of occurrence of various molecular fragment types, and the subsequent partial least squares (PLS) regression analysis. Based on molecular hologram, alignment-free QSAR models could be rapidly and easily developed with highly statistical significance and predictive ability. In this paper, the toxicity data for a series of 83 benzene derivatives to the autotrophic Chlorella vulgaris (IGC50, negative logarithmic form of 6-h 50% population growth inhibition concentration in mmol/l) were subjected to HQSAR analysis and this resulted in a model with a high predictive ability. The robustness and predictive ability of the model were validated by "leave-one-out" (LOO) cross-validation procedure and an external testing set. The influence of fragment distinction parameters and fragment size on the quality of the HQSAR model have been also discussed.

[External irradiation combined with intracavitary brachytherapy for esophageal cancer]

OBJECTIVE

To study the long-term treatment results and acute irradiation response as well as complications following external irradiation combined with intracavitary brachytherapy.

METHODS

After loading intracavitary brachytherapy was used for patients with esophageal cancer. In 92 patients with esophageal cancer, 47 (group A) were treated with external irradiation only, and 45 (group B) with external irradiation and brachytherapy. The doses were 60.0 Gy - 70.0 Gy per 6-7 week for external irradiation, using 8 or 10 MV liner accelerator, and 5.0-8.0 Gy per fraction for intracavitary therapy.

RESULTS

There was a significant difference in acute response and complications as well as local recurrence rate between the two groups (P < 0.05). The survival rates of groups A and B at 1,3 and 5 years were 59.6%, 25.6%, 10.6% and 80.0%, 46.7%, 26.7% respectively (P < 0.05 respectively, using chi2 test). The complications related to intracavitary irradiation were esophageal perforation, esophagorrhagia, esophagotracheal fistula and esophageal narrowing. 66 patients died and 9 lost follow-up, giving a follow up rate of 90.2%.

CONCLUSION

External irradiation combined with afterloading intracavitary brachytherapy for esophageal cancer can reduce the local recurrence and enhance the long-term survival but with an increase of complications compared with the patients treated with external irradiation alone.