III-V-on-silicon anti-colliding pulse-type mode-locked laser

An anti-colliding pulse-type III-V-on-silicon passively mode-locked laser is presented for the first time based on a III-V-on-silicon distributed Bragg reflector as outcoupling mirror implemented partially underneath the III-V saturable absorber. Passive mode-locking at 4.83 GHz repetition rate generating 3 ps pulses is demonstrated. The generated fundamental RF tone shows a 1.7 kHz 3 dB linewidth. Over 9 mW waveguide coupled output power is demonstrated.

Serum high mobility group box protein 1 as a clinical marker for ovarian cancer

The aim of the study was to evaluate the clinical value of serum high mobility group box chromosomal protein 1 (HMGB1) in ovarian cancer and analyze the correlation between HMGB1 and ovarian cancer clinicopathologic outcomes.A total of 105 patients with diagnosed epithelial ovarian cancer, 46 patients with ovarian benign disease and 33 healthy volunteers were enrolled from January 2011 through January 2013. Serum HMGB1 levels were analyzed by enzyme-linked immunosorbent assay.The mean value of serum HMGB1 levels in ovarian cancer patients (78.18±54.87ng/ml) was significantly higher than those in benign patients (33.98±9.97ng/ml) and healthy control (26.71±7.99ng/ml, p < 0.0001), respectively. The serum HMGB1 levels were 40.33±6.50ng/ml, 61.16±20.15ng/ml, 81.81±51.15ng/ml and 119.48±84.28ng/ml in patients with TNM stage I, II, III, and IV, respectively (p < 0.0001). There were 81 of the 105 ovarian cancer patients obtained complete remission, the serum HMGB1 levels before treatment(71.99±42.49ng/ml) were much higher than that at remission stage(42.10±15.48ng/ml) (p < 0.0001). During our investigating period, 28 ovarian cancer patients underwent recurrence, the serum HMGB1 levels were 75.54±39.50ng/ml in these recurrent ovarian cancer patients compared to 42.04±10.68ng/ml in non-recurrent ovarian cancer (p < 0.0001). None of the remission or recurrent patients came from benign ovarian tumor group.Our study suggests that HMGB1 may be a useful clinical marker for evaluating progression and predicting prognosis of ovarian carcinoma. Targeting HMGB1 production or release might have potential approaches for ovarian carcinoma treatment.

[Expression characteristics of epithelial markers in human embryonic stem cells differentiating into keratinocytes]

OBJECTIVE

To differentiate human embryonic stem cells (hESCs) into keratinocytes (K-hESCs) and analyse the expression characteristics of biomarkers of K-hESCs.

METHODS

The hESCs of line H9 were seeded on matrigel in mTeSR1 medium. The hESCs were directly differentiated into keratinocytes in epithelial differentiation medium with bone morphogenetic protein 4, retinoic acid and N2 supplement. The karyotype of K-hESCs was analyzed, comparing the gene expression differences of K-hESCs with human gingival epithelial cells (HGECs), human immortalized oral epithelial cells (HIOECs) and HaCaT by Real-time PCR. Molecular characteristics of the cell differentiation were observed throughout the process by immunocytochemical techniques.

RESULTS

H9-hESCs were successfully differentiated into the cells that exhibited characteristics of keratinocytes in epithelial differentiation medium. The karyotype of K-hESCs was 46, XX; and the keratinocyte gene p63 expression in K-hESCs was significantly lower than that in HaCaT (P < 0.05), but there was no significant difference of p63 expression in K-hESCs, comparing with that in HGECs and HIOECs (P > 0.05).

CONCLUSION

H9-hESCs could be directly differentiated into K-hESCs. The gene expression of K-hESCs was similar to that of epithelial cells in the early stage of monolayer cells differentiation with high proliferative activity.

Interleukin 8 enhances the immune response of ducks to avian influenza vaccine

Interleukins are reported to be valuable immunostimulants in enhancing the immune efficiency of conventional vaccines. In this study, the effect of expression of interleukin 8 (IL-8) on the immune response of ducks to avian influenza vaccine was investigated. The results showed that the serum antibody titer, lymphocyte transformation efficiency and serum interferon gamma (IFN-γ) level of ducks injected with avian influenza vaccine along with a plasmid expressing duck IL-8 were higher than those of ducks injected with conventional immunostimulant Astragalus polysaccharide (APS) or empty plasmid. Therefore, the duck IL-8 may be used as a good immunostimulant to enhance the immune efficiency of avian influenza vaccine in ducks.

Narrow-linewidth short-pulse III-V-on-silicon mode-locked lasers based on a linear and ring cavity geometry

Picosecond-pulse III-V-on-silicon mode-locked lasers based on linear and ring extended cavity geometries are presented. In passive mode-locked operation a 12 kHz -3dB linewidth of the fundamental RF tone at 4.7 GHz is obtained for the linear cavity geometry and 16 kHz for the ring cavity geometry. Stabilization of the repetition rate of these devices using hybrid mode-locking is also demonstrated.

Eight-year follow-up of patients with myasthenia gravis after thymectomy

PURPOSE

To depict the long-term outcome of patients with myasthenia gravis after thymectomy in combination with immunotherapy, and the factors that may potentially affect the outcome.

METHODS

The 306 patients with myasthenia gravis who underwent extended thymectomy from January 1984 to December 2011 at Tongji Hospital were retrospectively evaluated.

RESULTS

The patients consisted of 174 cases with thymoma and 132 cases without thymoma. Pharmaceutical treatment was tailored for each case during follow-up. Nine patients with thymomatous myasthenia gravis died during the perioperative period, and 297 patients were followed for 8.6 years. By their latest visits, 241 patients (81.1%) gained satisfactory efficacy, 24 cases died (8.1%), and 32 cases (10.8%) remained unchanged or deteriorated. Favorable factors for satisfactory efficacy included the presence of ocular myasthenia gravis before operation, no presence of thymoma, and lack of concomitant diseases. It is interesting to mention that, patients with non-thymomatous myasthenia gravis obtained significantly higher rates of complete stable remission and clinical remission than the patients with thymomatous myasthenia gravis.

CONCLUSIONS

Extended thymectomy combined with immunotherapy is a preferred treatment with a satisfactory long-term remission rate. Patients with non-thymomatous myasthenia gravis have a much more promising prognosis than the patients with thymomatous myasthenia gravis. However, appropriate caution must be taken to discontinue pharmaceutical therapy as relapse remains a major concern after a patient who has already undergone thymectomy becomes symptom-free.

Changes in hippocampal ultrastructure and vimentin expression in rhesus monkeys following selective deep hypothermia and blood occlusion

Previous studies have shown that selective cerebral profound hypothermia combined with antegrade cerebral perfusion can improve resistance to cerebral hypoxia-ischemia in monkeys. The aim of this study was to observe the effect of selective cerebral profound hypothermia on the ultrastructure and vimentin expression in monkey hippocampi after severe cerebral ischemia. Eight healthy adult rhesus monkeys were randomly divided into two groups: profound hypothermia (N = 5) and normothermia (N = 3). Monkeys in the profound hypothermia group underwent bilateral carotid artery and jugular vein occlusion for 10 minutes at room temperature. Ringer's solution at 4°C was then perfused through the right internal carotid artery and out of the right jugular vein, maintaining the brain temperature below 18°C. Sixty minutes later, cerebral blood flow was restored. The normothermia group underwent all procedures with the exception that the Ringer's solution was 37°C during perfusion. All animals in the profound hypothermia group were successfully resuscitated. No significant abnormalities of hippocampal morphology or ultrastructure were observed. In contrast, no monkeys were alive after perfusion in the normothermia group and they had abnormal hippocampal morphology and ultrastructure to different extents. Vimentin expression in the hippocampus was significantly lower in the profound hypothermia group (47.88% ± 1.66) than the normothermia group (79.51% ± 1.00; P < 0.01). We conclude that selective cerebral profound hypothermia following 10-min occlusion of the bilateral common carotid arteries was able to downregulate vimentin expression in the hippocampus and protect it from severe cerebral ischemia.

A novel fish cell line derived from the brain of Chinese perch Siniperca chuatsi: development and characterization

In this study, a continuous cell line (named as CPB) was established from Siniperca chuatsi brain and has been subcultured >140 times. CPB cell line predominantly consisted of fibroblast-like cells that could grow better in Leibovitz's L-15 supplemented with 10% foetal bovine serum at 28° C. Polymerase chain reaction amplification of 18s recombinant (r)RNA confirmed the origin of this cell line from S. chuatsi. The CPB cell line was cryopreserved at different passage levels and revived successfully with 80-90% survival. The cell line was further characterized by chromosome number and transfection. The CPB cells were highly susceptible to infectious spleen and kidney necrosis virus (ISKNV) with a titre of 6·58-6·62 log TCID50 ml(-1) and numerous ISKNV particles were observed in the cytoplasm by transmission electron microscopy. At the same time, ISKNV infection was confirmed by reverse transcriptase polymerase chain reaction, immunodot blot and individual challenge experiments. The development and characterization of a new brain cell line from S. chuatsi were described in this study and it could be used as an in vitro tool for propagation of ISKNV and gene expression studies.

QKI-5 suppresses cyclin D1 expression and proliferation of oral squamous cell carcinoma cells via MAPK signalling pathway

Oral squamous cell carcinoma (OSCC) is one of the most frequently occurring malignancies in the world. The RNA-binding protein quaking (QKI) is a newly identified tumour suppressor in multiple cancers, but its role in OSCC is currently unknown. The purpose of the present study was to clarify the relationship between QKI expression and OSCC development. We found QKI-5 expression to be significantly decreased in the oral cancer cell line CAL-27. QKI-5 overexpression also reduced the proliferation of CAL-27 cells, which correlated with cyclin D1. This regulative function of QKI-5 occurs by modulating the phosphorylation level of the mitogen-activated protein kinase (MAPK) pathway. Therefore this study shows that underexpression of tumour suppressor QKI-5 could activate the MAPK pathway and contribute to uncontrolled cyclin D1 expression, thus resulting in increased proliferation of oral cancer cells.

Mercury fluxes from volcanic and geothermal sources: an update

We review the state of knowledge on global volcanogenic Hg emissions to the atmosphere and present new data from seven active volcanoes (Poás, Rincón de la Vieja, Turrialba, Aso, Mutnovsky, Gorely and Etna) and two geothermal fields (Las Pailas and Las Hornillas). The variability of Hg contents (c. 4–125 ng m−3) measured in gaseous emissions reflects the dynamic nature of volcanic plumes, where the abundances of volatiles are determined by the physical nature of degassing and variable air dilution. Based on our dataset and previous work, we propose that an average Hg/SO2 plume mass ratio of c. 7.8×10−6 (±1.5×10−6; 1 SE, n=13) is best representative of open-conduit quiescent degassing. Taking into account the uncertainty in global SO2 emissions, we infer a global volcanic Hg flux from persistent degassing of c. 76±30 t a−1. Our data are derived from active volcanoes during non-eruptive periods and we do not have any direct constraint on the Hg flux during periods of elevated SO2 flux associated with large-scale effusive or explosive eruptions. This suggests that the time-averaged Hg flux from these volcanoes is even larger if the eruptive contribution is considered. Conversely, closed-conduit degassing and geothermal emissions contribute modest amounts of Hg.

Protective effects of sodium p-aminosalicylic acid on learning and memory via increasing the number of basal forebrain choline acetyltransferase neurons in manganese-exposed rats

This study was conducted to investigate the protective effects of sodium p-aminosalicylic acid (PAS-Na) on learning and memory via increasing the number of basal forebrain choline acetyltransferase (ChAT) neurons in manganese (Mn)-exposed rats. Male Sprague Dawley rats were divided into following groups: the normal control I, II, and III groups, the model I, II, and III groups, low- and high-dose PAS-Na treatment (L- and H-PAS) group, PAS-Na prevention (PAS-P) group, and PAS-Na treatment (PAS-T) group. The model I, II, and III groups, L- and H-PAS, and PAS-T groups received intraperitoneal (i.p.) injection of 15 mg/kg manganese chloride tetrahydrate (MnCl2·4H2O) for 3 or 12 weeks, while the normal control I, II, and III groups received i.p. injection of an equal volume of saline; L- and H-PAS and PAS-T groups received back subcutaneous (s.c.) injection of PAS-Na (100 and 200 mg/kg) for the next 5 or 6 weeks, whereas model I and II group received back s.c. injection of an equal volume of saline. However, PAS-P group received back s.c. injection of 200 mg/kg PAS-Na + i.p. injection of 15 mg/kg MnCl2·4H2O for 12 weeks. Mn exposure significantly reduced the ability of spatial learning and memory capability, while PAS-Na prevention recovered it. Mn decreased the number of ChAT-positive neurons in vertical limb nucleus of the basal forebrain diagonal band/horizontal limb nucleus of the basal forebrain diagonal band and ChAT protein activity and treatment or prevention with PAS-Na restored those comparable with control. In brief, our results showed that PAS-Na may have protective effects on learning and memory against Mn via increasing the number of ChAT-positive neurons and activity of ChAT protein.

A clinical analysis of uterine artery embolisation in the treatment of placenta praevia or placenta praevia state

The aim of this study was to investigate the efficiency of uterine artery embolisation (UAE) for postpartum haemorrhage (PPH) related to placenta praevia. A total of 45 women with placenta praevia or placenta praevia state underwent UAE before inducing labour. The locations of uterine artery and placenta were determined through selective and super-selective catheterisation into the internal iliac artery and uterine artery digital subtraction angiography (DSA). The target arteries were then super-selectively catheterised and embolised using small pieces of gelatin sponge. The above processes were repeated until the darkly stained areas of placenta were no longer developing. The success rate of UAE was 100%. There was no longer haemorrhage after embolisation for all the cases of labour induction and the average volume of blood loss was 56 ml. UAE is an effective, reliable and minimally traumatic treatment method for preventing postpartum haemorrhage after induction of labour in patients with placenta praevia state.

Biomechanical effects of vertebroplasty on thoracolumbar burst fracture with transpedicular fixation: a finite element model analysis

OBJECTIVE

To investigate the biomechanical effects of augmentation of the fractured vertebrae after posterior instrumentation.

METHODS

By simulating internal fixation plus augmentation with cement, eight tridimensional, anatomically detailed finite element models of the T11-L1 functional spinal junction were developed. Two kinds of models for mimicking different severity of the fracture were established according to the Denis' classification. Augmentation with cement was conducted after reduction with posterior fixation using a universal spine system. These models assumed a three-column loading configuration as follows: compression, anteflexion, extension, lateroflexion and axial rotation. Stress of the implants and spine was evaluated.

RESULTS

Data showed that for severely fractured models, augmentation apparently decreased the von Mises stresses by 50% for the rods and 40% for the screws, about 40% for the inferior endplate of T11, and 50% for the superior endplate of L1 in vertical compression and other load situations.

CONCLUSION

We should only apply vertebroplasty to prevent correction loss and implants failure based on the fact that it could significantly decrease stress of the instrumentations and spine when the vertebrae are severely fractured.

LEVEL OF EVIDENCE

Level IV, biomechanical study.

Developmental competence in vitro and in vivo of bovine IVF blastocyst after 15 years of vitrification

BACKGROUND

It is uncertain whether long-term cryopreservation affects embryonic development.

OBJECTIVE

This study was to investigate the effects of long-term cryopreservation on in vitro and in vivo developmental competence of bovine blastocysts.

METHODS

The blastocysts were randomly allocated into 3 groups based on the storage time: 0.5-year group, 1-year group and 15-years group. The thawed blastocysts were subjected to in vitro culture or embryo transplantation.

RESULT

Significantly lower survival rate (89.2%) and re-expansion rate (70.3%) of blastocysts were obtained from 15-years group compared with those of 0.5-year (97.5% and 87.5%) and 1-year (100% and 84.2%) groups (P < 0.05). There were no significant differences in the hatching rate (39.5% to 42.5%) among the three groups and the pregnancy rate between 1-year (35.0%) and 15-years (36.4%) groups.

CONCLUSIONS

Although in vitro developmental competence of the 15 years cryopreserved blastocysts was decreased slightly, the pregnancy outcome was not affected.

Aberrant TAL1 activation is mediated by an interchromosomal interaction in human T-cell acute lymphoblastic leukemia

Long-range chromatin interactions control metazoan gene transcription. However, the involvement of intra- and interchromosomal interactions in development and oncogenesis remains unclear. TAL1/SCL is a critical transcription factor required for the development of all hematopoietic lineages; yet, aberrant TAL1 transcription often occurs in T-cell acute lymphoblastic leukemia (T-ALL). Here, we report that oncogenic TAL1 expression is regulated by different intra- and interchromosomal loops in normal hematopoietic and leukemic cells, respectively. These intra- and interchromosomal loops alter the cell-type-specific enhancers that interact with the TAL1 promoter. We show that human SET1 (hSET1)-mediated H3K4 methylations promote a long-range chromatin loop, which brings the +51 enhancer in close proximity to TAL1 promoter 1 in erythroid cells. The CCCTC-binding factor (CTCF) facilitates this long-range enhancer/promoter interaction of the TAL1 locus in erythroid cells while blocking the same enhancer/promoter interaction of the TAL1 locus in human T-cell leukemia. In human T-ALL, a T-cell-specific transcription factor c-Maf-mediated interchromosomal interaction brings the TAL1 promoter into close proximity with a T-cell-specific regulatory element located on chromosome 16, activating aberrant TAL1 oncogene expression. Thus, our study reveals a novel molecular mechanism involving changes in three-dimensional chromatin interactions that activate the TAL1 oncogene in human T-cell leukemia.

Abstract P2-09-08: Therapeutic potential of the dual HER1/2 inhibitor AZD8931 in circumventing endocrine resistance

Background: Crosstalk between ER and HER-family signaling pathways has been suggested to play a role in the development of endocrine resistance. Preclinical studies have shown that AZD8931, a dual tyrosine kinase inhibitor (TKI) of HER1 (EGFR) and HER2, elicits an equipotent inhibition of HER1, HER2, and HER3 signaling, and is consequently more effective in blocking ligand-dependent HER signaling than the dual HER 1/2 TKI lapatinib. Using in vitro and in vivo models we investigated AZD8931's therapeutic potential in enhancing endocrine therapy and in overcoming the growth of tumor cells resistant to tamoxifen (Tam).

Materials and Methods: The effect of different TKIs (AZD8931 and lapatinib) on endocrine therapy [Tam and Fulvestrant (Ful)] was tested in ER+ MCF7 and T47D parental cells and their Tam-resistant derivatives (TamRes). In vitro growth, proliferation, and apoptosis were assessed using an in situ cell cytometer, EDU incorporation, and Annexin V-FITC/c-PARP, respectively. HER ligands in the parental and TamRes cells were profiled using RNASeq analysis of these lines. Western blot analysis was used to analyze the effect of AZD8931, lapatinib, and the HER1 TKI gefitinib on HER 1/2 pathway activation upon ligand stimulation. Nude mice with transplantable MCF7/TamRes xenografts at 200 mm3 were randomized to continued Tam, Tam+AZD8931, Fulvestrant (Ful), or Ful+AZD8931 treatments.

Results: We found that neither lapatinib nor AZD8931 significantly enhanced endocrine sensitivity in parental MCF7 breast cancer cells, although AZD8931 did enhance endocrine sensitivity in parental T47D cells. Furthermore, AZD8931 combined with either Tam or Ful inhibited cell growth more profoundly than lapatinib in the T47D TamRes cell model, and was significantly, though modestly, more potent than lapatinib in the MCF7 TamRes model when combined with Tam. In both TamRes models, AZD8931 significantly inhibited cell proliferation and induced apoptosis, with the highest effects seen in combination with Ful. Interestingly, multiple HER ligands are upregulated in both MCF7 and T47D TamRes models, which could explain the superiority of AZD8931 over lapatinib in these models. Indeed, in EGF and heregulin (HRG) stimulated conditions, AZD8931 more potently inhibited HER signaling (i.e., phosphorylated (p) levels of HER1/2, MAPK, and AKT) than lapatinib or gefitinib. Finally, AZD8931 significantly delayed the growth of MCF7 TamRes xenografts in the presence of continued Tam or Ful. These tumors were also inhibited by Ful alone, but the strongest inhibition was achieved by Ful and AZD8931 in combination. However, despite the marked tumor growth delay, no tumor regression was found in any of these treatments.

Conclusion: This study provides evidence that AZD8931 has greater inhibitory efficacy than lapatinib in endocrine resistant models that are dependent on ligand activation of the HER pathway. Although the AZD8931 combination with Ful robustly slowed growth of TamRes tumors in vivo, the absence of tumor regression suggests that additional escape pathways are also involved and should also be targeted to fully circumvent tamoxifen resistance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-08.

Genetic variations in MOV10 and CACNB2 are associated with hypertension in a Chinese Han population

Human hypertension is a complex, multifactorial disease. Multiple variants associated with hypertension have been identified in the large numbers of genome-wide association studies, meta-analysis, and case-control studies. The present study investigated the association between the single nucleotide polymorphisms (SNPs) of five candidate genes and the susceptibility and prognosis of hypertension in a Chinese Han population. A hospital-based case-control study in a Chinese Han population was carried out, including 500 hypertension patients and 506 healthy controls. The five SNP markers were detected using the Sequenom MassArray(®) iPLEX System. The association of genotypes with susceptibility to hypertension was analyzed using odds ratio, with 95% confidence interval and logistic regression. All five variants conformed to Hardy-Weinberg proportions in the controls. No significant differences were noted in the genotype distributions for AGTR1, PRRC2A, and CALCA polymorphisms in patients with hypertension (N = 500) and healthy controls (N = 506). SNP rs2932538, a variant in MOV10, was found to be significantly associated with an increased risk of hypertension. However, SNP rs4373814, a variant in CACNB2, showed a relevant association with a decreased risk of hypertension. In conclusion, the results of our case-control study confirmed the significant association of the SNP rs2932538 in MOV10 and SNP rs4373814 in CACNB2 with an increased risk of hypertension in a Chinese Han population, suggesting that the SNP rs2932538 may be a poor prognostic indicator for hypertension, while SNP rs4373814 may be a good prognostic indicator for hypertension in the same region. However, our findings need to be replicated in larger epidemiological and functional studies.

A treatment for large defects of the tibia caused by infected nonunion: Ilizarov method with bone segment extension

OBJECTIVES

To investigate the efficacy of the Ilizarov technique with bone segment extension in tibial infected nonunion.

METHODS

From September 2003 to June 2011, we treated 30 patients (21 males, 9 females; age 19-49 years, mean 34.1 years) for tibial infected nonunion with bone defects. Eleven cases were compound fractures internally fixed with steel plates, nine were compound fractures internally fixed with IM Nails, eight were compound fractures externally fixed with external fixation devices, and two were closed fractures internally fixed with steel plates. All 30 patients underwent debridement followed by the Ilizarov technique using bone segment extension.

RESULTS

After follow-up of 12 months-6 years (mean 29 months), stable union of fracture was achieved in all 30 patients. The time from bone fracture to union was 6-24 months, mean 8.8 months; external fixation was in place for 8-14 months, mean 10 months. External fixation index was 41 days/cm. Complications were three cases of pin site infection, one skin allergy, two fractures malunion, one early mineralization and one wire breakage. There were no cases of deep infection, nonunion or stiffness of the knee joint. According to the Paley fracture healing score criteria, 30 cases had excellent outcomes and two were good.

CONCLUSIONS

The Ilizarov technique with bone segment extension is effective in treating tibial infected nonunion with large bone defects.

Sequencing-based gene network analysis provides a core set of gene resource for understanding thermal adaptation in Zhikong scallop Chlamys farreri

Marine organisms are commonly exposed to variable environmental conditions, and many of them are under threat from increased sea temperatures caused by global climate change. Generating transcriptomic resources under different stress conditions are crucial for understanding molecular mechanisms underlying thermal adaptation. In this study, we conducted transcriptome-wide gene expression profiling of the scallop Chlamys farreri challenged by acute and chronic heat stress. Of the 13 953 unique tags, more than 850 were significantly differentially expressed at each time point after acute heat stress, which was more than the number of tags differentially expressed (320-350) under chronic heat stress. To obtain a systemic view of gene expression alterations during thermal stress, a weighted gene coexpression network was constructed. Six modules were identified as acute heat stress-responsive modules. Among them, four modules involved in apoptosis regulation, mRNA binding, mitochondrial envelope formation and oxidation reduction were downregulated. The remaining two modules were upregulated. One was enriched with chaperone and the other with microsatellite sequences, whose coexpression may originate from a transcription factor binding site. These results indicated that C. farreri triggered several cellular processes to acclimate to elevated temperature. No modules responded to chronic heat stress, suggesting that the scallops might have acclimated to elevated temperature within 3 days. This study represents the first sequencing-based gene network analysis in a nonmodel aquatic species and provides valuable gene resources for the study of thermal adaptation, which should assist in the development of heat-tolerant scallop lines for aquaculture.

Inter-relationships among diet, obesity and hippocampal-dependent cognitive function

Intake of a Western diet (WD), which is high in saturated fat and sugar, is associated with deficits in hippocampal-dependent learning and memory processes as well as with markers of hippocampal pathology. In the present study, rats were trained to asymptote on hippocampal-dependent serial feature negative (FN) and hippocampal-independent simple discrimination problems. Performance was then assessed following 7 days on ad libitum chow and after 10, 24, 40, 60, and 90 days of maintenance on WD, on ketogenic (KETO) diet, which is high in saturated fat and low in sugar and other carbohydrates, or continued maintenance on chow (CHOW). Confirming and extending previous findings, diet-induced obese (DIO) rats fed WD showed impaired FN performance, increased blood-brain barrier (BBB) permeability, and increased fasting blood glucose levels compared to CHOW controls and to diet-resistant (DR) rats that did not become obese when maintained on WD. For rats fed the KETO diet, FN performance and BBB integrity were more closely associated with level of circulating ketone bodies than with obesity phenotype (DR or DIO), with higher levels of ketones appearing to provide a protective effect. The evidence also indicated that FN deficits preceded and predicted increased body weight and adiposity. This research (a) further substantiates previous findings of WD-induced deficits in hippocampal-dependent FN discriminations, (b) suggests that ketones may be protective against diet-induced cognitive impairment, and (c) provides evidence that diet-induced cognitive impairment precedes weight gain and obesity.

Investigation of 20 non-HLA (human leucocyte antigen) psoriasis susceptibility loci in Chinese patients with psoriatic arthritis and psoriasis vulgaris

BACKGROUND

Recently, a number of non-HLA (human leucocyte antigen) psoriasis genetic susceptibility loci have been identified through genome-wide association studies, but data on their association with psoriatic arthritis (PsA) are lacking.

OBJECTIVES

To investigate recently identified psoriasis susceptibility loci in a cohort of Chinese patients with PsA, psoriasis vulgaris (PsV) and healthy controls.

METHODS

Twenty single-nucleotide polymorphisms (SNPs) from 20 loci were selected for genotyping in 379 patients with PsA, 595 patients with PsV and 1181 healthy controls using the MassARRAY platform (Sequenom, San Diego, CA, U.S.A.). Data handling, quality control and association were performed using PLINK software, v. 1.07. The Cochran-Armitage trend test was used to test the genotype-phenotype association.

RESULTS

PsA showed a significant association with markers at TNIP1 (rs17728338, P = 2.20 × 10(-8)), IL28RA (rs4649203, P = 5.04 × 10(-6)), IL12B (rs2082412, P = 3.82 × 10(-5)), ERAP1 (rs27524, P = 1.25 × 10(-3)), PTTG1 (rs2431697, P = 1.22 × 10(-3)) and GJB2 (rs3751385, P = 1.48 × 10(-3)) when compared with the control group. In PsV a significant association was found for IL28RA (rs4649203, P = 9.53 × 10(-7)), TNIP1 (rs17728338, P = 1.21 × 10(-4)) and ERAP1 (rs27524, P = 1.17 × 10(-3)). The allele frequencies were not statistically different between PsA and PsV except for SNPs at IL12B and ZNF816A with a nominal P-value of 0.04 and 0·01, respectively.

CONCLUSIONS

This study provides evidence for the involvement of ERAP1, IL28RA, GJB2 and PTTG1 loci in PsA susceptibility and confirmed the previously reported association with PsA and PsV. These results support the hypothesis that genetic aetiology of psoriasis is the same in both PsA and PsV and also support the higher genetic component of PsA than PsV.

Low expression of Mfn2 is associated with mitochondrial damage and apoptosis in the placental villi of early unexplained miscarriage

INTRODUCTION

Early miscarriage is the most common complication of pregnancy and in many cases the etiology is not clearly understood. We aim to profile the expression of Mfn2 and mitochondrial damage in villous tissues, in order to determine the underlying mechanism of unexplained miscarriage.

METHODS

We investigated placental villous samples of 30 women with early unexplained miscarriage (miscarriage group) and 30 women with normal pregnancy (control group). Immunohistochemistry and western blotting were used to detect the Mfn2 expression. We observed trophoblastic cell apoptosis with TUNEL and analyzed Bcl-2 and Bax levels by western blotting. Transmission electron microscopy was used to analyze mitochondrial morphology and phosphomolybdic acid colorimetric method was used to measure the ATP content of all villous samples.

RESULTS

Mfn2 staining showed extra-nuclear localization in the trophoblastic cells. Compared with the control group, the levels of Mfn2 and Bcl-2 were markedly decreased (P < 0.01), while both the levels of Bax protein and apoptosis index (AI) were increased in the miscarriage group (P < 0.01). Mfn2 levels positively correlated with Bcl-2, but negatively correlated with Bax. Moreover, compared to the control group (33.8 ± 6.5 μmol/g), ATP levels in the miscarriage group were significantly decreased (15.8 ± 4.8 μmol/g). In addition, obvious impairment of mitochondrial function was observed in trophoblastic cells from the unexplained miscarriage group.

CONCLUSION

Mitochondrial morphologic and functional changes were observed in trophoblastic cells, and in relation with apoptosis, may be correlated with low levels of Mfn2. Deficient expression of Mfn2 in trophoblastic cells could be an important cause of early miscarriage.

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.

Abstract P6-10-03: The PKC inhibitor PKC412 antagonizes breast cancer cell growth and enhances tamoxifen sensitivity

Background: AIB1 (SRC-3, NCoA3), a member of the p160/steroid receptor coactivators family, plays a critical role in cell growth and proliferation. In estrogen receptor-alpha positive (ER+) breast cancer (BC) cells, it coactivates estrogen- and additional transcription factors-dependent gene transcription, reducing the antagonistic activity of tamoxifen and resulting in tamoxifen resistance (TR). We have previously shown that BC patients whose tumors expressed high levels of both AIB1 and HER-2 had worse outcomes with tamoxifen therapy, suggesting that AIB1 may be an important diagnostic and therapeutic target. Our findings that knocking down AIB1 attenuates ER signaling and inhibits breast cancer cell growth further indicate that the manipulation of AIB1 level could be an approach to treating BC and overcoming TR. Recently, it has been shown that protein kinase C (PKC) isoforms phosphorylate AIB1 and prevent its proteasome-mediated degradation. The present study was carried out to test if the multi-targeted kinase and PKC inhibitor PKC412 (midostaurin) is capable of promoting degradation of AIB1, inhibiting BC cell growth, and promoting tamoxifen antagonistic activity.

Methods: The ER+ MCF7, T47D, and ZR75-B BC cells and their tamoxifen-resistant derivatives (TR) were used. The Methylene Blue assay was employed to measure cell viability of BC cell lines after treatment with PKC412 or the combination of PKC412 with tamoxifen. To determine the impact of PKC412 on AIB1 and ER proteins and mRNA levels, we used immunoblotting and RT-qPCR, respectively.

Results: PKC412 successfully inhibited the growth of MCF7, T47D, and ZR75-B cells, and their tamoxifen-resistant derivatives. Treatment with PKC412 depleted AIB1 protein and reduced the level of ER protein without significant alteration in AIB1 mRNA level. Consequently, ER signaling was disrupted, as reflected by decreased expression of ER target genes such as GREB1. PKC412 also enhanced tamoxifen's antagonistic activity in the parental cell lines and sensitized tamoxifen-resistant MCF7 and ZR75-B cells to tamoxifen.

Conclusions: The results of this study suggest that the multi-targeted kinase and PKC inhibitor PKC412 can post-translationally destabilize AIB1 protein and ER, inhibiting BC cell growth and viability. PKC412 enhances tamoxifen's antagonistic activity on BC growth; furthermore, it sensitizes tamoxifen-resistant cells to tamoxifen. Thus, PKC412 is a promising agent to treat BC and, in combination with tamoxifen, to delay or overcome TR.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-10-03.

Abstract PD01-01: Overcoming endocrine therapy resistance related to PTEN loss by strategic combinations with mTOR, AKT, or MEK inhibitors

Background: Hyperactive PI3K signaling is associated with a more aggressive subtype of estrogen receptor (ER) positive breast cancer (BC) and with endocrine resistance. Loss or downregulation of PI3K's inhibitor PTEN is more common in basal and luminal B vs. luminal A BC. However, the role of PTEN in modulating response to various endocrine therapies is unclear. Here we investigated the effects of PTEN knockdown (KD) on endocrine sensitivity and the potential of multiple kinase inhibitors to restore and improve responses.

Methods: Nude mice bearing ER+ BC xenograft tumors of MCF7 cells stably expressing a doxycycline (Dox)-inducible PTEN-shRNA were randomized to four endocrine treatment groups [continued estrogen (E2) supplementation, or E2-deprivation (ED) alone or in combination with tamoxifen (Tam) or fulvestrant (Ful)]; all -/+ Dox. The effects of single or combined kinase inhibitors on these endocrine treatments -/+ Dox were studied in vitro using inhibitors (i) to mTOR (AZD2014, 0.2 μM), AKT (AZD5363, 1 μM), or MEK (Selumetinib/ARRY-142886, 1 μM). Cell growth, apoptosis, and ER and progesterone receptor (PR) signaling were analyzed using cell cytometry, qRT/PCR, and Western blotting. Synergism tests were used to examine the growth effects of the most promising combinatorial therapy with multiple kinase inhibitors in different endocrine settings.

Results: In wild-type (WT) PTEN xenograft tumors, endocrine therapies were very effective, inducing frequent tumor regression. In PTEN KD tumors endocrine therapies were less effective — PTEN KD delayed tumor regression in all endocrine regimens and accelerated tumor progression in the Tam treated group. Furthermore, at day 250, only 1/8 and 0/7 tumors had developed resistance in the ED and the Ful (−Dox) groups, respectively, while with PTEN KD (+Dox), 7/15 and 5/15 tumors developed resistance to ED and to Ful. In vitro PTEN KD also induced resistance to all endocrine therapies. mRNA and/or protein levels of ER and PR were suppressed by PTEN KD and restored by mTORi and AKTi. In cells with WT PTEN, mTORi was highly effective with or without endocrine therapy. However, AKTi and MEKi were more effective in combination with endocrine therapy. All three inhibitors were less effective upon PTEN KD. The mTORi plus AKTi combination resulted in a potent synergistic inhibition in PTEN KD cells in the presence of E2 or with ED. In contrast, in the presence of Tam, AKTi plus MEKi, independent of PTEN status, was the most effective combination at the doses chosen. Finally, these inhibitors and combinations were more effective in the presence of Ful than ED or Tam in WT PTEN cells. AKTi combined with Ful was still highly effective even in PTEN KD cells, but mTORi and MEKi were less effective.

Conclusions: Our results suggest that PTEN loss renders endocrine therapy less effective in in vitro and in vivo experimental models. Single AKT/MEK kinase inhibitors are more potent in the presence of endocrine therapy. In PTEN KD cells, the activity of all three kinase inhibitors is largely diminished, except for AKTi in the presence of fulvestrant. Kinase inhibitor combinations are generally more effective, but the optimal combinations vary by PTEN status and type of endocrine therapy.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD01-01.

Microenvironment-dependent homeostasis and differentiation of epidermal basal undifferentiated keratinocytes and their clinical applications in skin repair

Skin homeostasis is maintained by controlling the balance between proliferation and differentiation of epidermal stem cells. The microenvironment, including extrinsic stresses, growth factors, soluble molecules, cell-ECM and cell-cell communications, plays an important role in cell fate determination in vivo and in vitro. In response to external signals, keratinocytes cooperate with other cell types to modulate and facilitate the wound microenvironment during wound healing; however, the aberrant signals or conjunctions in the environment will lead to pathologic abnormalities. In addition, despite some drawbacks, the epidermal stem-cellbased bioengineered skin substitutes have greatly improved the quality of cutaneous repair. Thus, exploring the characteristics and regulation mechanisms of microenvironment-dependent homeostasis and differentiation of epidermal basal undifferentiated keratinocytes is necessary to understand skin development and wound repair and to design novel therapeutic strategies for skin wound healing.

Insights into bone marrow-derived mesenchymal stem cells safety for cutaneous repair and regeneration

Wound healing involves the orchestration of a complex process of interactions between numerous types of cell, components of extracellular matrix and signalling molecules following injury, which is usually a highly successful biological course to reconstruct the integrity of the skin. Nevertheless, when skin is severely damaged, the injured skin is limited in its ability to repair itself and possibly results in the hypertrophic scars or so-called keloids, and non healing wound or ulcer. Bone marrow-derived mesenchymal stem cells (BM-MSCs) are being clinically explored as a promising therapy in the field of tissue repair and regeneration. However, potential risks associated with these cell-based therapies remain uncertain. The aim of this review is to summarise the safety issues accompanying the administration of BM-MSCs for acute or chronic skin repair and regeneration. More importantly, this review highlights the requirement for fundamental research to improve future clinical application of these strategies, as well as for regulatory authorities to establish clinical criteria to identify the qualitative requirements for the manufacture process of cells products, which will ensure the manufacture process of the best benefit-to-risk ratio of cell-based therapy for the patients.

Epidemic reemergence in adaptive complex networks

The dynamic nature of a system gives rise to dynamical features of epidemic spreading, such as oscillation and bistability. In this paper, by studying the epidemic spreading in growing networks, in which susceptible nodes may adaptively break the connections with infected ones yet avoid being isolated, we reveal a phenomenon, epidemic reemergence, where the number of infected nodes is incubated at a low level for a long time and then erupts for a short time. The process may repeat several times before the infection finally vanishes. Simulation results show that all three factors, namely the network growth, the connection breaking, and the isolation avoidance, are necessary for epidemic reemergence to happen. We present a simple theoretical analysis to explain the process of reemergence in detail. Our study may offer some useful insights, helping explain the phenomenon of repeated epidemic explosions.