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

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

Effects of quaternary ammonium chain length on antibacterial bonding agents

The objectives of this study were to synthesize new quaternary ammonium methacrylates (QAMs) with systematically varied alkyl chain lengths (CL) and to investigate, for the first time, the CL effects on antibacterial efficacy, cytotoxicity, and dentin bond strength of bonding agents. QAMs were synthesized with CL of 3 to 18 and incorporated into Scotchbond Multi-Purpose (SBMP) bonding agent. The cured resins were inoculated with Streptococcus mutans. Bacterial early attachment was investigated at 4 hrs. Biofilm colony-forming units (CFU) were measured after 2 days. With CL increasing from 3 to 16, the minimum inhibitory concentration and minimum bactericidal concentration were decreased by 5 orders of magnitude. Incorporating QAMs into SBMP reduced bacterial early attachment, with the least colonization at CL = 16. Biofilm CFU for CL = 16 was 4 log lower than SBMP control (p < .05). All groups had similar dentin bond strengths (p > .1). The new antibacterial materials had fibroblast/odontoblast viability similar to that of commercial controls. In conclusion, increasing the chain length of new QAMs in bonding agents greatly increased the antibacterial efficacy. A reduction in Streptococcus mutans biofilm CFU by 4 log could be achieved, without compromising bond strength and cytotoxicity. New QAM-containing bonding agents are promising for a wide range of restorations to inhibit biofilms.

Involvement of RP105 and toll-like receptors in the activation of mouse peritoneal macrophages by Staphylococcus aureus

Staphylococcus aureus is the aetiological agent of many hospital- and community-acquired infections. Toll-like receptor 2 (TLR2) has been shown to play a crucial role in the host defence against S. aureus infection. The aim of this study is to investigate the roles of the heterogeneous TLR family proteins TLR2, TLR4 and RP105 during S. aureus infection. Peritoneal macrophages from mice were exposed to S. aureus. Their production of inflammatory cytokines and chemokines, their expression of cell-surface markers and interactions between TLR2, TLR4 and RP105 were assessed in the presence or absence of inhibitory antibodies against TLR2, TLR4/MD-2 and RP105/MD-1 complexes. Our results demonstrate that not only TLR2 but also TLR4 and RP105 are involved in the response of macrophages to S. aureus, that TLR2, TLR4 and RP105 physically interact with each other during S. aureus infection, and that TLR2, TLR4 and RP105 both cooperate and play unique roles in the production of inflammatory cytokines (TNF-α, IL-12p40 and IL-10) and chemokine (RANTES) by macrophages after S. aureus infection. This study characterizes the important roles that TLR2, TLR4 and RP105 play in host resistance against S. aureus infection.

Stro-1-positive human mesenchymal stem cells prolong skin graft survival in mice

BACKGROUND

Human mesenchymal stem cells (MSCs) and its stromal cell antigen 1 Stro-1 positive (Stro-1(+)) subgroup possess immunosuppressive properties. Our objective was to evaluate the in vivo inhibitory effect of MSCs and the Stro-1 subset.

METHODS

Isolated human MSCs from bone marrow-derived mononuclear cells of healthy adults, and Stro-1(+) cells were cultured before sorting. Female C57BL/6 mice and female BALB/c mice were used as donors and recipients in an allogeneic skin graft model, respectively. The recipients were divided randomly into 4 groups: (1) The Stro-1(+) MSCs group received 2 × 10(6) Stro-1(+) MSCs injected into irradiated recipients before skin grafting. (2) The MSC group (2 × 10(6)) injected into the irradiated recipient mice before skin grafting. (3) The irradiated control group just irradiated before skin grafting. (4) The syngenic control group included irradiated BALB/c mice that received skin from syngenic mice. The main data included skin graft survival times, histologic changes on hematoxylin and eosin (HE) staining and plasma transforming growth factor (TGF)-β concentrations in recipients measured by enzyme-linked immunosorbent assay (ELISA) before and after transplantation.

RESULTS

The skin graft survival time in the MSCs group (12.13 ± 3.34 days) was not significantly prolonged versus the irradiated controls (11.38 ± 1.01 days), but it was notably prolonged among the Stro-1(+) MSCs group (30.68 ± 5.89 days) compared with the irradiated control and the MSCs groups, respectively. The histology of skin grafts among the stro-1(+) group showed a clear structure. After grafting, plasma TGF-β concentrations were almost the same as before transplantation among the irradiated and the syngenic controls but significantly increased in the MSCs and Stro-1(+) MSCs groups.

CONCLUSIONS

Stro-1(+) MSCs induced greater prolongation of skin grafts in mice than unsorted MSCs; however, TGF-β expression did not contribute to this effect.

PTEN hypermethylation profiles of Chinese Kazakh patients with esophageal squamous cell carcinoma

Aberrant DNA methylation of promoter region CpG islands may serve as an alternative mechanism to genetic defects in the inactivation of tumor suppressor genes (TSGs) in human malignancies. The aim of this study was to examine the promoter methylation status of the PTEN TSG and its association with esophageal squamous cell carcinoma (ESCC) carcinogenesis in a Chinese Kazakh population, which is known to have a relatively high ESCC incidence and mortality. The methylation status of the PTEN promoter region was determined in patients with ESCC (n = 95) and healthy individuals (n = 65) using highly sensitive Sequenom Epityper assays. The methylation level of the PTEN gene was significantly higher in patients with ESCC than in healthy controls. The median methylation level was 10.0% (interquartile range [IQR]: 7.0-11.0%) in patients with ESCC and 6.0% in controls (IQR: 4.0-9.0%; P = 0.001). PTEN methylation levels were higher in male patients with ESCC than in male controls, whereas a trend toward significance was observed between female patients with ESCC and female controls (P = 0.005 and P = 0.086, respectively). The PTEN methylation level was associated with histopathological grade and lymph node metastasis in patients with ESCC (P = 0.002 and P = 0.009, respectively). To our knowledge, this is the first report to show the presence of PTEN promoter CpG hypermethylation in ESCC and its association with tumor metastasis.

Effectiveness of dishwashing liquids in removing chlorothalonil and chlorpyrifos residues from cherry tomatoes

Washing is the most practical way to remove pesticide residues in fruits and vegetables. Two commonly used kitchen dishwashing liquids (detergents) in Chinese market were tested for enhanced removal of chlorpyrifos (CHP) and chlorothalonil (CHT) in cherry tomatoes by soaking the cherry tomatoes in the detergent solutions. The critical micelle concentrations of detergent A and detergent B were about 250 mg L(-1) and 444 mg L(-1), respectively. Detergent A had a higher solubilizing ability for pesticides and hence washing effectiveness than detergent B. The apparent solubility of CHP increased with increasing detergent concentration, while that of CHT remained comparatively invariant independent of detergent concentration within the tested range. The apparent solubility of CHP was also consistently higher in solutions of both detergents as compared to CHT. Due probably to its lower logKow value, CHT was more readily washed off cherry tomatoes than CHP. In terms of washing, a duration of 10-20 min was sufficient for removal of pesticides on cherry tomatoes in distilled water and detergent solutions. The effectiveness of removing pesticides increased with increasing detergent concentration from 50 mg L(-1) to 5 g L(-1), with up to 80% CHT and 42% CHP removed. Multiple washing further increased pesticide removal. Adding 10% acetic acid to lower pH or increasing washing temperature favored pesticide removal, but 10% NaCl produced the shielding effect and substantially reduced the effectiveness of detergent A for pesticide removal.

PAK4 kinase-mediated SCG10 phosphorylation involved in gastric cancer metastasis

Superior cervical ganglia 10 (SCG10), as a microtubule (MT) destabilizer, maintains MT homeostasis and has a critical role in neuronal development, but its function in tumorigenesis has not been characterized. In the present study, we demonstrated that p21-activated kinase 4 (PAK4)-mediated SCG10 phosphorylation regulates MT homeostasis in metastatic gastric cancer. Our results indicate that SCG10 is a physiological substrate of PAK4, which is phosphorylated on serine 50 (Ser50) in a PAK4-dependent manner. Phosphorylated SCG10 regulated MT dynamics to promote gastric cancer cell migration and invasion in vitro and metastasis in a xenograft mouse models. Inhibiting PAK4, either by LCH-7749944 or RNA interference, resulted in the inhibition of Ser50 phosphorylation and a blockade to cell invasion, suggesting that PAK4-SCG10 signaling occurs in gastric cancer cell invasion. Moreover, we demonstrated a strong positive correlation between PAK4 and phospho-Ser50 SCG10 expression in gastric cancer samples. We also showed that high expression of SCG10 phospho-Ser50 is highly correlated to an aggressive phenotype of clinical gastric cancer. These findings revealed a novel function of SCG10 in promoting invasive potential of gastric cancer cells, suggesting that blocking PAK4-mediated SCG10 phosphorylation might be a potential therapeutic strategy for metastasis of gastric cancer.

Generating high-brightness electron beams via ionization injection by transverse colliding lasers in a plasma-wakefield accelerator

The production of ultrabright electron bunches using ionization injection triggered by two transversely colliding laser pulses inside a beam-driven plasma wake is examined via three-dimensional particle-in-cell simulations. The relatively low intensity lasers are polarized along the wake axis and overlap with the wake for a very short time. The result is that the residual momentum of the ionized electrons in the transverse plane of the wake is reduced, and the injection is localized along the propagation axis of the wake. This minimizes both the initial thermal emittance and the emittance growth due to transverse phase mixing. Simulations show that ultrashort (~8 fs) high-current (0.4 kA) electron bunches with a normalized emittance of 8.5 and 6 nm in the two planes, respectively, and a brightness of 1.7×10(19) A rad(-2) m(-2) can be obtained for realistic parameters.

RhoA modulates functional and physical interaction between ROCK1 and Erk1/2 in selenite-induced apoptosis of leukaemia cells

RhoA GTPase dysregulation is frequently reported in various tumours and haematologic malignancies. RhoA, regulating Rho-associated coiled-coil-forming kinase 1 (ROCK1), modulates multiple cell functions, including malignant transformation, metastasis and cell death. Therefore, RhoA/ROCK1 could be an ideal candidate target in cancer treatment. However, the roles of RhoA/ROCK1 axis in apoptosis of leukaemia cells remain elusive. In this study, we explored the effects of RhoA/ROCK1 cascade on selenite-induced apoptosis of leukaemia cells and the underlying mechanism. We found selenite deactivated RhoA/ROCK1 and decreased the association between RhoA and ROCK1 in leukaemia NB4 and Jurkat cells. The inhibited RhoA/ROCK1 signalling enhanced the phosphorylation of Erk1/2 in a Mek1/2-independent manner. Erk1/2 promoted apoptosis of leukaemia cells after it was activated. Intriguingly, it was shown that both RhoA and ROCK1 were present in the multimolecular complex containing Erk1/2. GST pull-down analysis showed ROCK1 had a direct interaction with GST-Erk2. In addition, selenite-induced apoptosis in an NB4 xenograft model was also found to be associated with the RhoA/ROCK1/Erk1/2 pathway. Our data demonstrate that the RhoA/ROCK1 signalling pathway has important roles in the determination of cell fates and the modulation of Erk1/2 activity at the Mek–Erk interplay level.

Occult macrophage activation syndrome in systemic-onset juvenile idiopathic arthritic syndrome--a case report

Macrophage activation syndrome (MAS) is a severe and life-threatening complication of rheumatic disorders in children. We described a 9-year-old girl in whom MAS developed as a complication of systemic juvenile idiopathic arthritis (S-JIA) at onset with obvious hemophagocytosis presented in the marrow. She suffered from high fever and generalized rash subsequently joints swelling for two weeks before admission. Physical examination revealed mild cervical lymphadenopathy and hepatosplenomegaly. Laboratory findings were: abnormal liver enzymes, increased triglyceride and ferritin levels, anemia .Hyperplasia of hemophagocytic macrophages was remarkable in her bone marrow. Methylprednisolone and cyclosporin therapy resulted in clinical and laboratory improvement. It is unusual that hemophagocytosis presented in the marrow at onset of So-JIA without obvious abnormal coagulation profile, thrombocytopenia and leucopenia. It seemed that MAS may be occult at onset of SJIA. It may be integral to the pathogenesis of SJIA. The proper cyclosporine serum lever at the onset of MAS is as high as 200-300 ng/ml.

Comparison of patient-specific internal gross tumor volume for radiation treatment of primary esophageal cancer based separately on three-dimensional and four-dimensional computed tomography images

To compare the target volume, position and matching index of the patient-specific internal gross tumor volume (IGTV) based on three-dimensional (3D) and four-dimensional (4D) computed tomography (CT) images for primary esophageal cancer. Twenty-nine patients with primary thoracic esophageal cancer underwent 3DCT and 4DCT scans during free breathing. IGTVs were constructed using three approaches: combining the gross target volumes from the 10 respiratory phases of the 4DCT dataset to produce IGTV10 ; IGTV2 was acquired by combining the two extreme phases; and IGTV3D was created from the 3DCT-based gross target volume by enlarging the 95th percentile of motion in each direction measured by the 4DCT. 0.16 cm lateral (LR), 0.14 cm anteroposterior (AP) and 0.29 cm superoinferior (SI) in the upper; 0.18 cm LR, 0.10 cm AP and 0.63 cm SI in the middle; and 0.40 cm LR, 0.58 cm AP and 0.82 cm in the lower thoracic esophagus could account for 95% of respiratory-induced tumor motion. The centroid position shift between IGTV10 and IGTV2 was all below 0.10 cm, and less than 0.20 cm between IGTV10 and IGTV3D . IGTV10 was bigger than IGTV2 ; the mean value of matching index for IGTV2 to IGTV10 was 0.87 ± 0.05, 0.85 ± 0.06 and 0.83 ± 0.05 for upper, middle and distal thoracic esophageal tumors, respectively, and just 0.57 ± 0.11, 0.56 ± 0.13 and 0.40 ± 0.03 between IGTV3D and IGTV10 . 4DCT-based IGTV10 is a reasonable patient-specific IGTV for primary thoracic esophageal cancer, and IGTV2 is considered as an acceptable alternative to IGTV10 . However, it seems unreasonable to use IGTV3D substitute IGTV10 .

A new strategy for identification of currant (Ribes nigrum L.) cultivars using RAPD markers

We developed a new approach using RAPD fingerprints to distinguish 37 currant cultivars from northeastern China based on optimization of RAPD by choosing 11 nucleotide primers and strict screening PCR annealing temperature. We found that the manual cultivar identification diagram (MCID) approach clearly developed fingerprints from 8 different primers that were useful for cultivar identification; a cultivar identification diagram (CID) was readily constructed. This CID allows efficient currant cultivar identification, providing information to separate all the currant cultivars from each other, based on the detail polymorphic bands from the corresponding primers, which were marked in the correct positions on the currant CID. According to the CID, 10 currant cultivars in 5 groups were randomly selected for the referable and workable identification of this strategy. The results proved the workability and efficiency of the MCID method, facilitating the identification of fruit cultivars with DNA markers. This MCID approach will be useful for early identification of seedlings in the nursery industry and protection of cultivar rights.

Observation of a charged charmoniumlike structure in e+ e- → π+ π- J/ψ at sqrt[s] = 4.26 GeV

We study the process ee+ e- → π+ π- J/ψ at a center-of-mass energy of 4.260 GeV using a 525  pb(-1) data sample collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross section is measured to be (62.9±1.9±3.7)  pb, consistent with the production of the Y(4260). We observe a structure at around 3.9  GeV/c2 in the π(±)J/ψ mass spectrum, which we refer to as the Z(c)(3900). If interpreted as a new particle, it is unusual in that it carries an electric charge and couples to charmonium. A fit to the π(±)J/ψ invariant mass spectrum, neglecting interference, results in a mass of (3899.0±3.6±4.9)  MeV/c2 and a width of (46±10±20)  MeV. Its production ratio is measured to be R = (σ(e+ e- → π(±)Z(c)(3900)(∓) → π+ π- J/ψ)/σ(e+ e- → π+ π- J/ψ)) = (21.5±3.3±7.5)%. In all measurements the first errors are statistical and the second are systematic.

Treatment with Fms-like tyrosine kinase 3 ligand reverses lung dendritic cell immunoparalysis and ameliorates zymosan-induced secondary lung injury in mice

Depletion and dysfunction of dendritic cells in the lung can induce local immunoparalysis, which often leads to multiple organ dysfunction syndrome (MODS)-associated mortality. A therapeutic strategy that reverses this immunoparalysis is required. In the present study, we examined the effects of in vivo Fms-like tyrosine kinase 3 ligand (Flt3L) treatment on zymosan (zym)-induced secondary lung injury and dendritic cell (DC) immunoparalysis. BALBc mice were divided randomly into four groups (20/group): (1) sham [intraperitoneal (i.p.) saline] + vehicle [subcutaneous (s.c.) 0·01% mouse serum albumin]; (2) sham + Flt3L (s.c.); (3) zym (i.p.) + vehicle; and (4) zym + Flt3L. Injections were for 9 consecutive days; 12 days later we examined: survival rate (monitored for 12 days); lung tissue histopathology (haematoxylin and eosin staining); plasma indices of lung function (pH, PaO(2) , PaCO(2) , HCO(3) (-) ); DC subsets in lung tissue; and lung DCs production of interleukin (IL)-12p70 and IL-10. Zym administration resulted in increased mortality associated with significant lung histopathological changes and abnormal blood gas indices; however, these pathological changes were ameliorated by Flt3L treatment. Zym injections also resulted in significant reductions in DC subsets recovered from lungs [CD11c(+) major histocompatibility complex (MHC)-II/I-A(d+) , CD11c(+) CD11b(+) and CD11c(+) B220(+) ]. Importantly, in-vivo Flt3L treatment reversed these trends for DC immunoparalysis by increasing the percentages of recovered DC subsets concomitant with increased DC production of IL-12 p70 and decreased IL-10 production. These results suggest that Flt3L may have therapeutic potential for reversing DC immunoparalysis and ameliorating lung injury secondary to MODS.

ERCC1, defective mismatch repair status as predictive biomarkers of survival for stage III colon cancer patients receiving oxaliplatin-based adjuvant chemotherapy

Background:

Excision repair cross-complementation group 1 (ERCC1) expression status has been identified as a candidate marker for predicting efficacy of oxaliplatin (OX) treatment for metastatic colorectal cancer (CRC) in several trials. Also, an association between expression of mismatch repair (MMR) genes and favourable postoperative survival in stage II CRC receiving 5-FU chemotherapy has been identified. It is unknown if the expression of ERCC1 protein and MMR status are associated with survival of stage III colon cancer receiving OX-based chemotherapy.

Methods:

Immunohistochemistry (IHC) analysis of the expression of MMR and ERCC1 was performed on tumour tissue of 255 patients with stage III colon cancer. In all, 95 patients received fluoropyrimidine-based chemotherapy and 160 patients received OX-based chemotherapy. A predictive model for 5-year disease-free survival (DFS) and overall survival (OS) was constructed using Kaplan–Meier analysis, logistic and Cox regression.

Results:

Patients who were treated with OX-based therapy with positive ERCC1 tumours had lower 5-year DFS (54%) and OS (60%) than those with negative ERCC1 tumours (72% and 78%, respectively; DFS HR: 1.98, 95% confidence interval (CI): 1.19–3.31, P=0.009; OS HR: 2.44, 95% CI: 1.37–4.34, P=0.02). Excision repair cross-complementation group 1 status did not impact DFS or OS in fluorouracil group (DFS HR: 1.16, 95% CI: 0.63–2.14, P=0.62; OS HR: 1.16, 95% CI: 0.63–2.14, P=0.63), whereas MMR status had no impact on DFS or OS in either group.

Conclusion:

Excision repair cross-complementation group 1 status is highly predictive of which patients will benefit from the addition of OX to 5-FU for stage III colon cancer. Mismatch repair status had no predictive value in this setting.