The utility of MRI for pre-operative T and N staging of gastric carcinoma: a systematic review and meta-analysis

OBJECTIVE

To perform a meta-analysis and literature review regarding the diagnostic accuracy of MRI for pre-operative tumour depth invasion (T) and regional lymph node invasion (N) staging of gastric carcinoma (GC).

METHODS

Articles were identified through systematic search of Medline, PubMed, Cochrane Library, Web of Science, Springerlink and several Chinese databases. The study quality was assessed by the quality assessment for studies of diagnostic accuracy. 2 reviewers independently extracted and assessed the data from 11 eligible studies. A meta-analysis was then carried out. Subgroup and sensitivity analyses were also performed.

RESULTS

11 studies (439 patients) were finally included in the current review. Among these studies, the significant evidence of heterogeneity was only discovered for specificity in T4 stage (I(2) = 59.8%). Pooled sensitivity and specificity of MRI to diagnose T stage tumour (T3-4 vs T1-2) were 0.93 [95% confidence interval (CI), 0.89-0.96] and 0.91 (95% CI, 0.87-0.95), respectively. Pooled estimates of sensitivity and specificity of MRI to diagnose N stage tumour (N0 vs N+) were 0.86 (95% CI, 0.80-0.92) and 0.67 (95% CI, 0.54-0.79), respectively. Subgroup analyses showed that diffusion-weighted imaging was more helpful for T staging.

CONCLUSION

The present systematic review suggests that MRI has a good diagnostic accuracy for pre-operative T staging of GC and should be widely used in clinical work. However, the ability for N staging is relatively poor on MRI.

ADVANCES IN KNOWLEDGE

In the pre-operative staging of GC, MRI was a useful tool and may enhance accuracy for the T staging of advanced GC.

Efficacy of transcatheter aortic valve implantation in patients with aortic stenosis and reduced LVEF. A systematic review

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is safe and effective for patients with aortic stenosis (AS) who have a high operative risk. However, there is still debate on the effect of TAVI in AS patients with reduced left ventricular ejection fraction (REF). The objective of the review is to clarify the efficacy of TAVI and the impact of REF on the 30-day and midterm mortality in these patients.

METHODS

Studies on TAVI were searched in PubMed, Embase, and the Cochrane Library databases and were included in this review following predefined criteria. Data were extracted and pooled risk ratios (RR) were synthesized to explore the relationship between REF and 30-day plus midterm mortality.

RESULTS

Twenty-eight studies comprising 14,099 patients were included in the analysis of the association of REF with the prognosis of patients after TAVI. An average increase in left ventricular ejection fraction of 8-10 % was observed among these patients after TAVI. REF was not related to the 30-day mortality [RR = 1.90, 95 % confidence interval (CI) = 0.80-4.47]; however, it was related to the midterm mortality (RR = 1.49, 95 %CI = 1.14-1.93) of patients undergoing TAVI. Patients with low-flow and low-gradient AS had a higher 30-day mortality (RR = 1.54, 95 %CI = 1.11-2.13) and midterm mortality rate (RR = 1.69, 95 %CI = 1.33-2.14) compared with AS patients without these characteristics. The mortality of TAVI patients was significantly lower than that of those undergoing conservative therapy, and was similar to that of patients undergoing surgical aortic valve replacement.

CONCLUSION

REF was not associated with 30-day mortality, but it was associated with the midterm mortality of TAVI patients. Patients with REF could benefit from TAVI compared with conservative therapy.

Effective cryopreservation of golden Syrian hamster embryos by open pulled straw vitrification

Golden Syrian hamster embryos are difficult to cryopreserve due to their high sensitivity to cryoprotectants and in vitro handling. The objective of this study is to develop a robust open pulled straw (OPS) vitrification technique for cryopreserving hamster embryos at various developmental stages. We first systematically tested the concentrations of cryoprotectants and the exposure times of two-cell embryos to various vitrification solutions. We identified pretreatment of two-cell embryos with 10% (v/v) ethylene glycol (EG) + 10% (v/v) dimethylsulfoxide (DMSO) for 30 s followed by exposure in the vitrification solution, EDFS30 (containing 15% EG + 15% DMSO), for 30 s before plunging into liquid nitrogen (two-step exposure method) as the optimal OPS vitrification protocol. We then investigated the resourcefulness of this protocol for vitrifying hamster embryos at different developmental stages. The results showed that high blastocyst rates from embryos vitrified at two-cell, four-cell, eight-cell, or morula stage (62%, 78%, 80%, or 72%, respectively), but not those verified at pronuclear (0%) or blastocyst stage (24%; P < 0.05), were achieved by this protocol. When embryos vitrified at the two-cell stage were recovered and then directly transferred to recipient females, 29% of them developed to term, a development rate not significantly different (P > 0.05) from the 40% birth rate of the unvitrified controls. In conclusion, we have developed an effective two-step OPS vitrification protocol for hamster embryos.

Precision Measurement of the (e^{+}+e^{-}) Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station

We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e^{+}+e^{-}) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale).

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station

A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy.

Mixed Nipple Infections Caused by Variant of BPV3 and a Putative New Subtype of BPV in Cattle

Bovine papilloma is a chronic and proliferative skin and mucosal wart caused by Bovine papillomavirus (BPV). In June, 2013, a leaf-and flat-shaped wart disease was observed on the nipple skins in a cattle farm in Xinjiang. To diagnose the disease, we collected the diseased skins for pathological biopsy and DNA analysis by PCR amplification using a pair of degenerate primers FAP59 and FAP64. Sequencing and phylogenetic analysis showed that the infection was caused by a variant of BPV3 and putatively a new subtype of BPV (BPV/CHI-SW1, belonging to the Xi papillomavirus genus). This is the first report of mixed infection caused by variant of BPV3 and BPV (putatively new subtype) in China, and would be of importance for the molecular epidemiological study of the disease.

Blocking TGF-β inhibits breast cancer cell invasiveness via ERK/S100A4 signal

OBJECTIVE

Targeted down-regulation of TGF-β expression inhibits invasion and metastasis in breast cancer cells. However, the mechanism that TGF-β functions by remains largely unknown. In the present study we report the mechanism of ERK1/2 dependant S100A4 regulation by TGF-β and its possible role in TGF-β-mediated tumour invasion in vitro.

MATERIALS AND METHODS

Small interfering RNA targeting TGF-β1 (TGF-β1 siRNA) were stably transfected into the breast cancer cell line MDA231. The TGF-β1 siRNA/9MDA231 cells were then treated with TGF-β1 (5 ng/ml) or treated with PD98059 (25 μM) or transfected into S100A4 siRNA before TGF-β1 treatment. The cells were used in several in vitro analyses, including migration, invasion, angiogenesis, and signaling assays. A wound-healing assay was used to determine migration of the cells in culture and a Boyden chamber transwell assay was used for invasion. In vitro angiogenesis studies using conditioned medium in HMEC-1 cells.

RESULTS

Inhibition of TGF-β1 expression by TGF-β1 siRNA transfection in MDA231 cells showed significant decrease migration, invasion and angiogenesis in vitro. TGF-β1 siRNA/MDA231 cells treated with 5 ng/ml TGF-β1 for 24 hs restored the invasive ability of TGF-β1 siRNA/MDA231 cells. TGF-β1 treatment could not increase migration, invasion and angiogenesis in TGF-β1 siRNA/MDA231 cells when treated with 25 μM PD98059 or transfected with S100A4 siRNA before TGF-β1 treatment. Analysis of TGF-β1 signaling pathways showed a decrease in p-ERK1/2 activation and an decrease in S100A4 expression. Interestingly, TGF-β1 regulated S100A4 via ERK1/2 signalling.

CONCLUSIONS

Our findings showed that blocking TGF-β inhibits breast cancer cell invasiveness, migration and angiogenesis via ERK/S100A4 signalling. Therapies targeting the TGF-β signaling pathway may be more effective to prevent progression in breast cancer.

107 GENETIC INACTIVATION OF THE Sry GENE IN ARGALI WILD AND ROMNEY DOMESTIC SHEEP WITH CRISPR/Cas SYSTEMS FOR PRODUCING SEX-REVERSED FEMALE ANIMALS

The Tibetan Argali (Ovis ammon hodgsoni), a wild sheep of the subfamily Caprinae (Bovidae), primarily found in the Tibetan Plateau, is categorized as near threatened on the International Union for Conservation of Nature (IUCN) Red List. For the conservation of this species, we have achieved the cloning of a full-term live Argali lamb (died shortly after birth) from a male Argali cell line that has been cryopreserved for more than 20 years. While working towards the goal of cloning a live Argali, we also recognised the need to establish a reproductive herd of animals by producing both fertile males and females. However, as in the case of Argali, it is difficult, and in some cases impossible, to obtain male and female cell lines from an endangered mammalian species. Therefore, for demonstrating a proof of concept of using an assisted reproduction technology (ART) for the conservation of endangered species or reviving extinct species, we used the Argali as an experimental model to produce both fertile males and females through ART. The Sry gene plays a central role in mammalian sex determination: mutations in the Sry gene result in the development of XY females; in mice, Sry knockout (KO) results in fertile XY females. Therefore, we created sex-reversed Argali cell lines through the KO of the Sry gene. In parallel, for potentially comparing the fertility of sex-reversed XY females between the Argali and domestic sheep [Romney (Ovis aries)], we also knocked out the Sry gene in the domestic sheep. Specifically, we used the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system to introduce mutations to the high-mobility group (HMG) box of the Sry gene. Skin fibroblasts from either adult Argali or Romney sheep were cultured in DMEM (HyClone) supplemented with 10% fetal bovine serum (FBS). Cells were harvested at 100% confluence with 0.25% trypsin-EDTA and transfected with the CRISPR/Cas DNA constructs by using the Amaxa Nucleofector system. For each experiment, 106 cells were transfected with 5 μg of CRISPR/Cas DNA constructs. After 72 hours post-transfection, cells were harvested, with half being used for genomic DNA isolation (for examining KO efficiency) and the other half for limited dilution for obtaining single-cell-derived colonies. With the Surveyor assay and a restriction enzyme digestion assay (successfully knocked-out cells lose the Dde I site in the HMG box of the Sry gene, rendering resistance to Dde I digestion), we demonstrated that the Sry KO efficiency was about 10% both in Argali and Romney sheep. By screening single-cell-derived colonies from the transfected Romney sheep cells, an Sry-KO cell line harboring a 2-nucleotide deletion in the HMG box was successfully established. Multiple vials of cells from this Sry-KO cell line have been cryopreserved and will be used for animal cloning via somatic cell nuclear transfer (SCNT) in the sheep-breeding season this fall.

39 EFFECT OF FOLLICULAR SIZE OF CYTOPLAST DONOR ON CLONING EFFICIENCY IN GOATS

In goats, oocytes derived from small follicles (<3 mm in diameter) have low developmental competence after IVF (Crozet et al. 1995). However, their performance is compatible to oocytes derived from large follicles (>3 mm) when intracytoplasmic sperm injection is used (Jimenez-Macedo et al. 2006). No data are currently available on the ability of oocytes derived from small follicles to support development to term after somatic cell nuclear transfer (SCNT) in goats. Here we evaluated the effect of follicular size of cytoplast donor on cloning efficiency in goats. Seven rounds of oocyte maturation and nuclear transfer were carried out on separate days. During each replicate, oocytes were collected separately from large follicles (LF, n = 378) and small follicles (SF, n = 981) from the same group of ovaries. First, only large follicles (>3 mm) were dissected and rinsed, and then an ovary was moved to another dish to dissect the rest of the follicles. The groups of oocytes derived from LF and SF were treated separately throughout the process including maturation, SCNT, embryo culture and embryo transfers. Neonatal skin fibroblasts derived from transgenic goats were used as nuclear donors in this study. Nine embryo transfers were conducted for LF group and 12 for the SF group. Oocytes from SF had significantly lower rate of nuclear maturation compared to oocytes derived from LF (33.5% ± 3.7 v. 54.3% ± 5.4; P < 0.01). There was no difference in fusion rate between these 2 groups (66 v. 69%; 215/325 v. 138/199; SF v. LF). Additionally, we found no statistical difference in Day 30 pregnancy rate (42% v. 33%; SF v. LF group) or birth rate (2 healthy kids produced from each of the groups, 16.7% v. 22.2%; SF v. LF). The results demonstrate that oocytes from small follicles have similar competence to support development to term as oocytes derived from large follicles following SCNT in goats. This work was supported by the Utah Multidisciplinary Arrhythmia Consortium and Utah Agricultural Experiment Station project #1100.

High-resolution MRI of the intraparotid facial nerve based on a microsurface coil and a 3D reversed fast imaging with steady-state precession DWI sequence at 3T

BACKGROUND AND PURPOSE

3D high-resolution MR imaging can provide reliable information for defining the exact relationships between the intraparotid facial nerve and adjacent structures. The purpose of this study was to explore the clinical value of using a surface coil combined with a 3D-PSIF-DWI sequence in intraparotid facial nerve imaging.

MATERIALS AND METHODS

Twenty-one healthy volunteers underwent intraparotid facial nerve scanning at 3T by using the 3D-PSIF-DWI sequence with both the surface coil and the head coil. Source images were processed with MIP and MPR to better delineate the intraparotid facial nerve and its branches. In addition, the SIR of the facial nerve and parotid gland was calculated. The number of facial nerve branches displayed by these 2 methods was calculated and compared.

RESULTS

The display rates of the main trunk, divisions (cervicofacial, temporofacial), and secondary branches of the intraparotid facial nerve were 100%, 97.6%, and 51.4% by head coil and 100%, 100%, and 83.8% by surface coil, respectively. The display rate of secondary branches of the intraparotid facial nerve by these 2 methods was significantly different (P < .05). The SIRs of the intraparotid facial nerve/parotid gland in these 2 methods were significantly different (P < .05) at 1.37 ± 1.06 and 1.89 ± 0.87, respectively.

CONCLUSIONS

The 3D-PSIF-DWI sequence combined with a surface coil can better delineate the intraparotid facial nerve and its divisions than when it is combined with a head coil, providing better image contrast and resolution. The proposed protocol offers a potentially useful noninvasive imaging sequence for intraparotid facial nerve imaging at 3T.

First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.

29 EFFECT OF EMBRYO CULTURE LENGTH ON PRODUCTION OF CLONED TRANSGENIC GOATS

The yield of blastocysts and hatched blastocysts using in vitro production (IVP) in goats are still low. The development of caprine embryos is frequently arrested at the 8- to 16-cell stage, indicating suboptimal culture conditions (Jimenez-Macedo et al. 2005 Theriogenology 64, 1249–1262). Our goal was to produce transgenic goats by somatic cell nuclear transfer (SCNT) and further determine whether the length of embryo culture has an effect on development to term. We compared the efficiency of transferring single-cell embryos 12 h post-activation to transferring 4- to 8-cell embryos cultured for 60 h post-activation. Nine transgenic goats from 2 cell lines were produced through SCNT. Somatic donor cells were obtained from 2 sources: adult fibroblasts and fetal fibroblasts. Adult fibroblasts were obtained from a transgenic doe skin biopsy. Fetal fibroblasts were isolated from a 25-day-old fetus and then electroporated with a pcDNA3.1DV5-MHC-TGF-β1cys33ser vector, followed by G418 selection, screening, and subsequent use for SCNT. Oocytes with >4 layers of cumulus cells were collected by slicing abattoir ovaries and matured in vitro for 21 to 23 h. After being denuded, oocytes presenting a first polar body were enucleated and received a donor cell from 1 of the 2 cell lines. Fused embryos were then activated for 5 min in 5 µM ionomycin, followed by 4 h in 2 mM DMAP with 5 µg of cycloheximide mL–1. Activated embryos were cultured in G1 medium with 5 mg of BSA mL–1 for either 12 or 60 h post-activation, followed by surgical transfer into the oviducts of recipients synchronized to show estrus within 12 h of SCNT. Overall, 376 embryos were transferred into 23 recipients. Pregnancy was examined by ultrasonography on Day 30 post-transfer. No pregnancy losses were observed after Day 30 of gestation. All kids were born live (42% of recipients receiving embryos cultured for 12 h gave birth, compared with only 9% when cultured for 60 h). The data (Table 1) suggest that a longer culture time in vitro significantly reduces viability of cloned embryos. Table 1.Twelve-hour versus 60-h embryo culture This work was supported by Utah Agricultural Experiment Station project no. 1100.

30 GENERATION OF CLONED TRANSGENIC GOATS WITH CARDIAC SPECIFIC OVEREXPRESSION OF TRANSFORMING GROWTH FACTOR β1

Transforming growth factor β1 (TGF-β1) has a potent profibrotic function and is central to signaling cascades involved in interstitial fibrosis, which plays a critical role in the pathobiology of cardiomyopathy and contributes to diastolic and systolic dysfunction. In addition, fibrotic remodeling is responsible for generation of re-entry circuits that promote arrhythmias (Bujak and Frangogiannis 2007 Cardiovasc. Res. 74, 184–195). Due to the small size of the heart, functional electrophysiology of transgenic mice is problematic. Large transgenic animal models have the potential to offer insights into conduction heterogeneity associated with fibrosis and the role of fibrosis in cardiovascular diseases. The goal of this study was to generate transgenic goats overexpressing an active form of TGFβ-1 under control of the cardiac-specific α-myosin heavy chain promoter (α-MHC). A pcDNA3.1DV5-MHC-TGF-β1cys33ser vector was constructed by subcloning the MHC-TGF-β1 fragment from the plasmid pUC-BM20-MHC-TGF-β1 (Nakajima et al. 2000 Circ. Res. 86, 571–579) into the pcDNA3.1D V5 vector. The Neon transfection system was used to electroporate primary goat fetal fibroblasts. After G418 selection and PCR screening, transgenic cells were used for SCNT. Oocytes were collected by slicing ovaries from an abattoir and matured in vitro in an incubator with 5% CO2 in air. Cumulus cells were removed at 21 to 23 h post-maturation. Oocytes were enucleated by aspirating the first polar body and nearby cytoplasm by micromanipulation in Hepes-buffered SOF medium with 10 µg of cytochalasin B mL–1. Transgenic somatic cells were individually inserted into the perivitelline space and fused with enucleated oocytes using double electrical pulses of 1.8 kV cm–1 (40 µs each). Reconstructed embryos were activated by ionomycin (5 min) and DMAP and cycloheximide (CHX) treatments. Cloned embryos were cultured in G1 medium for 12 to 60 h in vitro and then transferred into synchronized recipient females. Pregnancy was examined by ultrasonography on day 30 post-transfer. A total of 246 cloned embryos were transferred into 14 recipients that resulted in production of 7 kids. The pregnancy rate was higher in the group cultured for 12 h compared with those cultured 36 to 60 h [44.4% (n = 9) v. 20% (n = 5)]. The kidding rates per embryo transferred of these 2 groups were 3.8% (n = 156) and 1.1% (n = 90), respectively. The PCR results confirmed that all the clones were transgenic. Phenotype characterization [e.g. gene expression, electrocardiogram (ECG), and magnetic resonance imaging (MRI)] is underway. We demonstrated successful production of transgenic goat via SCNT. To our knowledge, this is the first transgenic goat model produced for cardiovascular research. This work was supported by the Utah Science Technology and Research Initiative, Utah Multidisciplinary Arrhythmia Consortium.

Ghrelin promotion of oocyte maturation via ERK1/2 pathway in ovis aries

Ghrelin has recently garnered increasing attention in biomolecular studies. Ghrelin's growth hormone secretagogue receptor type 1a (GHS--R) is a pleiotropic modulator of diverse biological functions, including energy homeostasis and reproduction. This study sought to understand the ways in which ghrelin impacts ERK1/2 and p90rsk during the ovis aries oocyte maturation process. We applied different concentrations of ghrelin and of ghrelin receptor inhibitor (D--Lys3--GHRP--6) to ovis aries oocytes and observed the effects on the ERK1/2 and p90rsk pathway. The ERK1/2 and p90rsk pathway plays an essential role in the in vitro maturation of ovis aries oocytes. This study discovered that ERK1/2 and p90 rsk pathway, during the ovis aries oocyte maturation, was associated with maturation of ovis aries oocyte in vitro.

Interleukin-25 promotes basic fibroblast growth factor expression by human endothelial cells through interaction with IL-17RB, but not IL-17RA

BACKGROUND

Unlike other IL-17 family members, the Th2-derived cytokine IL-25 (IL-17E) induces (promotes) Th2 responses. One or both of the two receptors for IL-25 (IL-17RA, IL-17RB) is expressed on inflammatory cells and tissue structural cells, suggesting that in addition to promoting Th2-type inflammation IL-25 may also act on structural cells at sites of Th2-type inflammation such as in the asthmatic bronchial mucosa to promote remodelling changes.

OBJECTIVE

Our previous studies showed elevated expression of IL-25 and IL-17RB immunoreactivity in asthmatic airways with co-localization of the latter to endothelial cells. We therefore hypothesized that IL-25 acts on endothelial cells through this receptor to induce production of the key angiogenic and remodelling cytokine basic fibroblast growth factor (bFGF).

METHODS

Polymerase chain reaction (PCR) immunocytochemistry/immunohistochemistry and ELISA were employed to detect expression of IL-17RB, IL-17RA and bFGF by human vascular endothelial cells (HUVEC) and immunoreactivity for IL-25 and bFGF in asthmatic bronchial biopsies. Receptor-blocking antibodies, PCR and an in vitro angiogenesis assay were used to investigate whether IL-25 acts on IL-17RB or IL-17RA to induce bFGF expression and angiogenesis. PCR was also employed to investigate the signalling pathways involved in IL-25-mediated bFGF expression.

RESULTS

HUVEC constitutively expressed IL-17RB, IL-17RA and bFGF. Production of the latter was further increased by IL-25, but attenuated after blockade of the IL-17RB, but not the IL-17RA receptor. Neutralization of endogenous VEGF and bFGF completely abrogated IL-25-induced angiogenesis which was also inhibited by blocking IL-17RB, but not IL-17RA. The PI3K-specific inhibitor LY294002 also completely attenuated IL-25-induced bFGF expression. Immunoreactivity for IL-25 and bFGF was elevated in the asthmatic bronchial mucosa and the expression of each correlated with the other.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data support the hypothesis that IL-25 contributes to elevated bFGF in asthmatic airways by acting on the endothelial cell IL-17RB receptor through PI3K-signalling pathways. Targeting the pathways might benefit therapy of airways remodelling.

G-protein coupled receptor 120 is involved in glucose metabolism in fat cells

Free fatty acids (FFA) are closely related to insulin resistance in which proteins such as insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3 kinase (PI3K) and glucose transporter type 4 (GLUT4) are involved. Recent researches have shown that G-protein coupled receptor 120 (GPR120) is a receptor for medium and long chain FFA. This study aimed to evaluate the relationship between GPR120 and proteins related to the glucose metabolism. We used siRNA technique to down-regulate the GPR120 expression in 3T3-L1 cells before incubation with palmitic acid (PA), and evaluated the effect of GPR120 expression on the levels of IRS-1, PI3K and GLUT4 after PA induction. RT-PCR and western blot were performed to detect gene and protein levels in differentiated cells. RT-PCR result showed that GPR120 mRNA significantly increased in differentiated cells. GPR120-SiRNA transfection significantly down-regulated GPR120 gene and protein level in differentiated 3T3-L1 cells on day 5 after PA-induced and also decreased lipid droplets accumulated within the cells. SiRNA-mediated decreased of GRP120 was associated with significant reductions in gene and protein levels of IRS-1 and GLUT4. Our results showed that the expression level of GPR120 affected the expression of proteins related to the glucose metabolism, suggesting a contribution of GPR120 in the insulin resistance.

Engineered domain-based assays to identify individual antibodies in oligoclonal combinations targeting the same protein

Quantitation of individual monoclonal antibodies (mAbs) within a combined antibody drug product is required for preclinical and clinical drug development. We have developed two antitoxins, XOMA 3B and XOMA 3E, each consisting of three mAbs that neutralize type B and type E botulinum neurotoxin (BoNT/B and BoNT/E) to treat serotype B and E botulism. To develop mAb-specific binding assays for each antitoxin, we mapped the epitopes of the six mAbs. Each mAb bound an epitope on either the BoNT light chain (LC) or translocation domain (H(N)). Epitope mapping data were used to design LC-H(N) domains with orthogonal mutations to make them specific for only one mAb in either XOMA 3B or XOMA 3E. Mutant LC-H(N) domains were cloned, expressed, and purified from Escherichia coli. Each mAb bound only to its specific domain with affinity comparable to the binding to holotoxin. Further engineering of domains allowed construction of enzyme-linked immunosorbent assays (ELISAs) that could characterize the integrity, binding affinity, and identity of each of the six mAbs in XOMA 3B and 3E without interference from the three BoNT/A mAbs in XOMA 3AB. Such antigen engineering is a general method allowing quantitation and characterization of individual mAbs in a mAb cocktail that bind the same protein.

Insulin-like growth factor-1 boosts the developing process of condylar hyperplasia by stimulating chondrocytes proliferation

OBJECTIVE

The etiology of Condylar hyperplasia (CH) of human temporomandibular joint (TMJ) remains largely unknown. Our previous study has demonstrated that enriched insulin-like growth factor-1(IGF-1) was expressed in the proliferation and hypertrophic layers of CH cartilage. Accordingly, this study was aimed to investigate whether IGF-1 regulates CH chondrocytes proliferation in condylar cartilage overgrowth and explore the molecular mechanism of IGF-1 involved in.

METHODS

Chondrocytes were isolated from 6 CH and 3 normal cartilage (NC) specimens and cultured in alginate beads or monolayer, treated with IGF-1 or specific inhibitors such as 7-[trans-3-[(azetidin-1-yl)methyl]cyclobutyl]-5-(3-benzyloxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine (NVP-AEW541), U0126, and LY294002. Thereafter, cellular proliferation capacity was evaluated by Cell Viability Analyzer (alginate beads culture) or 3-(4,5-dimethylthiazo(-2-yl)-2,5-diphenyltetrazolium bromide (MTT) (monolayer culture). Gene expression levels of IGF-1, IGF-1 receptor (IGF-1R), collagen type II, type X and those genes associated with proliferation were evaluated by realtime PCR. Protein levels of IGF-1 and IGF-1R synthesized by CH chondrocytes were accessed by enzyme-linked immunosorbent assay (ELISA) and western blotting.

RESULTS

CH chondrocytes enhanced cellular proliferation capacity and expressed significantly higher levels of messenger RNA (mRNA) and protein expressions of IGF-1 and IGF-1R, as compared with NC chondrocytes. Furthermore, enriched IGF-1 enhanced CH chondrocytes proliferation, up-regulated the expressions of specific genes associated with cellular proliferation and elevated the gene expression of collagen type II A1 (COL2A1). Besides, IGF-1-mediated CH chondrocytes proliferation mainly depended on the mitogen-activated protein kinase (MAPK)-ERK pathway.

CONCLUSIONS

IGF-1 promotes human TMJ cartilage overgrowth in the developing process of CH by enhancing chondrocytes proliferation via MAPK-ERK pathway.

Association of Sterol Regulatory Element-Binding Transcription Factor Gene Polymorphisms with Ischaemic Stroke

OBJECTIVE: To explore the association between polymorphisms of the sterol regulatory element-binding transcription factor ( SREBF) gene and ischaemic stroke. METHODS: The SREBF1c 54G>C and SREBPF2 1784G>C genotypes were assessed using restriction fragment length polymorphism analysis in 446 Han Chinese ischaemic stroke patients and 355 Han Chinese control subjects without cerebrovascular disease. RESULTS: The frequencies of the SREBF2 1784G>C CC genotype and the C allele were significantly higher in the ischaemic stroke group than in controls. Patients with ischaemic stroke who had the SREBF2 1784G>C CC genotype had significantly lower high-density lipoprotein (HDL) levels, compared with ischaemic stroke patients and control subjects with the GC or GG genotypes. Multivariate logistic regression analysis revealed a significant positive association between SREBF2 1784G>C and ischaemic stroke; an inverse association was observed between HDL level and risk of ischaemic stroke. CONCLUSIONS: The CC genotype of the SREBF2 1784G>C polymorphism was associated with an increased risk of ischaemic stroke, possibly through decreasing the HDL level, which was inversely associated with the risk of ischaemic stroke.

Translational control of TWIST1 expression in MCF-10A cell lines recapitulating breast cancer progression

TWIST1 is a highly conserved basic helix-loop-helix transcription factor that promotes epithelial-mesenchymal transition (EMT). Its misregulation has been observed in various types of tumors. Using the MCF-10A-series of cell lines that recapitulate the early stages of breast cancer formation and EMT, we found TWIST1 to be upregulated during EMT and downregulated early in carcinogenesis. The TWIST1 3'UTR contains putative regulatory elements, including miRNA target sites and two cytoplasmic polyadenylation elements (CPE). We found that miR-580, CPEB1, and CPEB2 act as negative regulators of TWIST1 expression in a sequence-specific and additive/cooperative manner.

Domain-based assays of individual antibody concentrations in an oligoclonal combination targeting a single protein

Quantitation of individual monoclonal antibodies (mAbs) within a combined antibody drug product is required for preclinical and clinical drug development, including pharmacokinetic (PK), toxicology, stability, and biochemical characterization studies of such drugs. We have developed an antitoxin, XOMA 3AB, consisting of three recombinant mAbs that potently neutralize the known subtypes of type A botulinum neurotoxin (BoNT/A). The three mAbs bind nonoverlapping BoNT/A epitopes with high affinity. XOMA 3AB is being developed as a treatment for botulism resulting from BoNT/A. To develop antibody-specific assays, we cloned, expressed, and purified BoNT/A domains from Escherichia coli. Each mAb bound only to its specific domain with affinity comparable to the binding to holotoxin. mAb-specific domains were used to develop an enzyme-linked immunosorbent assay (ELISA) for characterization of the integrity and binding activity of the three mAbs in the drug product. An electrochemiluminescence bridging assay that is robust to interference from components in serum was also developed, and we demonstrate that it can be used for PK assays. This type of antigen engineering to generate mAb-specific domains is a general method allowing quantitation and characterization of individual mAbs in a mAb cocktail that binds the same protein and is superior to anti-idiotype approaches.

Preclinical pharmacology of TP1, a novel potent triple reuptake inhibitor with antidepressant properties

Triple reuptake inhibitors (TRIs) that block the dopamine transporter (DAT), norepinephrine transporter (NET), and serotonin transporter (SERT) are being developed as a new class of antidepressant that may have better efficacy and fewer side effects compared with traditional antidepressants. The purpose of this study was to characterize a new chemical entity, 4-[2-(dimethylamino)-1-(1-hydroxycyclohexyl)ethyl] phenyl 4-methoxybenzoate hydrochloride (TP1). TP1 was designed as a prodrug of desvenlafaxine. Competitive radioligand binding assays were performed using cells expressing the human dopamine (DA) transporter (hDAT), the human serotonin (5-HT) transporter (hSERT), and the human norepinephrine (NE) transporter (hNET) with K(i) values for TP1 of 190 nM, 2076 nM, and 1023 nM, respectively. Uptake assays were performed with IC(50) values for TP1 of 712 nM, 521 nM, and 628 nM, respectively. TP1 (0.06 mmol/kg, orally) rapidly penetrated rat brain and hypothalamus, translated into desvenlafaxine within 1 h, and demonstrated higher bioavailability and better pharmacokinetic properties than desvenlafaxine succinate (DVS). TP1 (0.06 mmol/kg, orally) significantly increased extracellular levels of DA, NE, and 5-HT compared with baseline in the rat hypothalamus by microdialysis assay. In dose-response assays, oral administration of TP1 reduced the time of immobility in a dose-dependent manner during tail suspension test and forced swimming test (FST). This antidepressant-like effect manifests in the absence of significant increases in motor activity even at doses of up to 32 mg/kg. The ability of TP1 to inhibit the reuptake of three biogenic amines closely linked to the etiology of depression may result in a therapeutic profile different from antidepressants that inhibit the reuptake of serotonin and/or NE.

Resistin-like molecule-β is a human airway remodelling mediator

Though implicated in vascular remodelling, a role for the resistin-like molecule (RELM)-β in human airway remodelling remains unexplored. We hypothesised that RELM-β expression is increased in the airways of asthmatics and regulates airways epithelial cell function. Expression of RELM-β in the bronchial mucosa and its concentrations in bronchoalveolar lavage (BAL) fluid from asthmatics and controls were measured by immunohistochemistry and ELISA, respectively. Proliferation assays, Western blotting, ELISA and real-time PCR were employed to detect effects of RELM-β on airways epithelial cells. RELM-β expression was increased in the bronchial mucosa and BAL fluid of asthmatics compared with controls. In the asthmatics, the numbers of mucosal RELM-β+ cells correlated inversely with forced expiratory volume in 1 s (r=-0.531, p=0.016), while the numbers of epithelial RELM-β+ cells correlated positively with those of mucin (MUC)5AC+ cells. In vitro, interleukin-13 enhanced RELM-β expression by primary human airways epithelial cells, while RELM-β itself acted on these cells to induce proliferation, expression of MUC5AC, extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK)-phosphatidylinositol 3-kinase (PI3K)/Akt phosphorylation and elevated expression of transforming growth factor-β2, epidermal growth factor and vascular endothelial growth factor. RELM-β has the potential to contribute to airway remodelling in diseases such as asthma by acting on epithelial cells to increase proliferation, mucin and growth factor production, at least partly via ERK/MAPK-PI3K/Akt signalling pathways.

Pituicytoma: case report and literature review

Pituicytoma is a rare primary tumour of the neurohypophysis or infundibulum, which masquerades as a pituitary adenoma. We present a pituicytoma case in a 45-year-old female presenting as a focal lesion of the neurohypophysis. This case report reviews the clinical, neuroimaging and histopathological features of this rare tumour in order to understand it better.

CvhSlicer: an interactive cross-sectional anatomy navigation system based on high-resolution Chinese visible human data

We introduce the design and implementation of an interactive system for the navigation of cross-sectional anatomy based on Chinese Visible Human (CVH) data, named CvhSlicer. This system is featured in real-time computation and rendering of high-resolution anatomical images on standard personal computers (PCs) equipped with commodity Graphics Processing Units (GPUs). In order to load the whole-body dataset into the memory of a common PC, several processing steps are first applied to compress the huge CVH data. Thereafter, an adaptive CPU-GPU balancing scheme is performed to dynamically distribute rendering tasks among CPU and GPU based on parameters of computing resources. Experimental results demonstrate that our system can achieve real-time performance and has great potential to be used in anatomy education.