[Effect and mechanism of interleukin-8 expression induced by wood smoke particles in primary human airway epithelial cells]

OBJECTIVE

To investigate the effect and mechanism of interleukin-8 expression induced by wood smoke particles (WSP) in primary human airway epithelial cells.

METHODS

Primary human bronchial epithelial cells (HBEC) were collected through fiberbronchoscopic brushing and incubated with different concentration of WSP (0, 12.5, 25.0, 50.0, 100.0 μg/ml). Levels of IL-8 protein in cell culture supernatant were measured using enzyme-linked immune sorbent assay. The specific inhibitors for epidermal growth factor receptor (EGFR) and p38 kinase signaling pathways were employed to pretreat HBEC, respectively, prior to incubation with 100 μg/ml WSP to investigate the mechanism of IL-8 expression induced by WSP.

RESULTS

The expression of IL-8 was significant increased in a dose-dependent manner after exposure HBEC to different concentration of WSP for 24h. The levels of IL-8 expression were (4546.67±1421.42) ρg/ml in (PD153035+WSP) group and (2803.33±865.00) ρg/ml in (SB203580+WSP) group respectively, which were significant decreased compared with the level of (12896.67±1373.11) ρg/ml in WSP group (P<0.05).

CONCLUSION

WSP could induce IL-8 expression by means of EGFR and p38 signaling pathways.

[Influencing factors of type 2 diabetes mellitus in Chinese: a Meta-analysis]

OBJECTIVE

To evaluate the influencing factors of type 2 diabetes mellitus in Chinese, and provide evidence for developing health promotion policy in the future.

METHODS

Relevant studies published from January 1997 to May 2015 were retrieved from PubMed, Medline, EBSCO, Science Direct, CBM, CNKI, VIP, and Wanfang Database. Quality evaluation of the included literatures was conducted according to the inclusion and exclusion criteria, followed by data extraction and Meta-analysis with software RevMan 4.4.2.

RESULTS

A total of 29 studies involving 92 970 subjects(11 150 cases and 81 820 controls)were included. The pooled OR and its 95% CI of each influencing factor were: overweight OR=1.66(1.49-1.85), abdominal obesity OR=1.98(1.31-3.01), family history of diabetes OR =3.13(2.52-3.87), smoking OR=1.46(1.24-1.72), drinking OR=1.19(1.09-1.29), hypertension OR=2.64(2.23-3.13), systolic blood pressure(SBP)OR=1.15(1.06-1.24), hyperlipoidemia OR=2.26(1.75-2.92), total cholesterol(TC)OR=1.87(1.14-3.08), triglyceride(TG)OR=1.73(1.23-2.44), history of coronary heart disease(CHD)OR=2.55(1.78-3.65), cerebrovascular accident(CVA)OR=2.21(1.62-3.02), dietary fat OR=0.52(0.27-0.99). The results of subgroup analysis identified 4 common influencing factors shared by the three subgroups, i.e. overweight, family history of diabetes, smoking and hypertension.

CONCLUSION

Overweight, abdominal obesity, family history of diabetes, smoking, drinking, hypertension, SBP, TC, TG, history of CHD, history of CVA, and subtypes of dietary fat are the influencing factors for type 2 diabetes mellitus in Chinese. Among these factors, overweight in recent 20 years, family history of diabetes, smoking and hypertension are persistent factors. More attention should be paid to overweight and obesity.

Reduced dietary protein level influences the free amino acid and gene expression profiles of selected amino acid transceptors in skeletal muscle of growing pigs

This study was conducted to evaluate the effect of reduced dietary protein level on growth performance, muscle mass weight, free amino acids (FAA) and gene expression profile of selected amino acid transceptors in different fibre type of skeletal muscle tissues (longissimus dorsi, psoas major, biceps femoris) of growing pigs. A total of 18 cross-bred growing pigs (Large White × Landrace × Duroc) with initial body weight (9.57 ± 0.67 kg) were assigned into three dietary treatments: 20% crude protein (CP) diet (normal recommended, NP), 17% CP diet (low protein, LP) and 14% CP diet (very low protein, VLP). The results indicated improved feed-to-gain ratio was obtained for pigs fed LP and NP diets (p < 0.01), while the pigs fed VLP diet showed the worst growth performance (p < 0.01). There was no significant difference in the weights of longissimus dorsi and psoas major muscle between LP and NP groups (p > 0.05). Majority of the determined FAA concentration of LP group were greater than or equal to those of NP group in both longissimus dorsi and psoas major muscle (p < 0.01). Further, the mRNA expression levels of sodium-coupled neutral amino acid transceptor 2, L-type amino acid transceptor 1 and proton-assisted amino acid transceptors 2 were higher in skeletal muscle tissue in LP group compared to those of the pigs fed NP or VLP diet. These results suggested that reduced dietary protein level (3 points of percentage less than recommended level) would upregulate the mRNA expression of amino acid transceptors to enhance the absorption of FAA in skeletal muscle of growing pigs. There seems to be a relationship between response of AA transceptors to the dietary protein level in skeletal muscle tissue of different fibre type. To illustrate the underlying mechanisms will be beneficial to animal nutrition.

[Diagnostic values of mitral inflow and mitral annulus diastolic velocity for heart failure with preserved ejection fraction]

OBJECTIVE

To explore the diagnostic values of ratios of early diastolic peak transmitral velocity(E) to late velocity(A) (E/A) and E to early diastolic peak mitral annulus velocity (E/E') for heart failure patients with preserved ejection fraction (HF-PEF).

METHODS

Two hundred and sixteen healthy people were divided into <50 years, 50-59 years, 60-69 years, and ≥70 years groups to clarify the impact of aging on E/A and E/E'. Two hundred and two newly diagnosed consecutive in-patients with HF-PEF and 221 age- and sex-matched non-heart-failure subjects with risk factors of HF-PEF (negative controls) were enrolled.The diagnostic values and cutoff points of E/A and E/E' for HF-PEF were derived from receiver operating characteristic curve (ROC) analysis.

RESULTS

E/A and E/E' were significantly different among age groups in healthy controls (all P<0.01). Compared with <50 years group, average E/A was lower and average E/E' was higher in ≥70 years group(both P<0.01). E/A ratio was less than 1 in 68%(71/105), E/E' was >8 cm/s in 48% (50/105)healthy people with age≥60 years. Neither E/A nor E/E' of HF-PEF patients was statistically different regarding to NYHA classification (grade Ⅱ, Ⅲ, Ⅳ), but NT-proBNP value increased in proportion to higher NYHA classification(P<0.01). The area of E/E' under ROC for diagnosing HF-PEF was 0.839(P<0.01), and the corresponding cutoff point was 9.5 with a sensitivity of 86% and a specificity of 69%. The areas of E/A (larger value or smaller value indicating positive) under ROC for diagnosing HF-PEF were 0.469 and 0.531, respectively(all P>0.05).

CONCLUSIONS

Aging exerts significant impacts on both E/A and E/E'. E/E' has moderate diagnostic accuracy while E/A is of limited value for diagnosing HF-PEF.

Base-catalyzed controllable reaction of 3-ylideneoxindoles with O-Boc hydroxycarbamates for the synthesis of amidoacrylates and spiroaziridine oxindoles

A base-catalyzed divergent reaction of 3-ylideneoxindoles and O-Boc hydroxycarbamates has been developed to provide various amidoacrylates and spiroaziridine oxindoles with high yields.

The flavonoid from Polygonum perfoliatum L. inhibits herpes simplex virus 1 infection

Herpes simplex virus 1 (HSV-1) is one of the most prevalent human pathogens in both industrialized and developing countries. This study was performed to analyze the antiviral activity of purified flavonoid from Polygonum perfoliatum L. against HSV-1 infection in vitro and in vivo. Flavonoid showed no inhibitory effect, when treated before virus infection, but it strongly inhibited viral replication and cell-to-cell spread which was vital for the virus's propagation. The therapeutic effect of the flavonoid in treating HSV-1 induced encephalitis was also investigated in mice. A dose-dependent increase of survival rate and mean survival time (MST) were observed in the flavonoid-treated mice. These results suggested that the flavonoid may be a viable therapeutic option for recurrent HSV-1 infection.

Bilateral repetitive transcranial magnetic stimulation for treatment-resistant depression: a systematic review and meta-analysis of randomized controlled trials

There has been concern regarding the use of controversial paradigms for repetitive transcranial magnetic stimulation (rTMS) to manage treatment-resistant depression (TRD). This meta-analysis assessed the efficacy of bilateral rTMS compared with unilateral and sham rTMS in patients with TRD. PubMed, Embase, CENTRAL, PsycINFO, Web of Science, EAGLE and NTIS databases were searched to identify relevant studies, and randomized controlled trials (RCTs) on bilateral rTMS for TRD patients were included. The response was defined as the primary outcome, and remission was the secondary outcome. Ten RCTs that included 634 patients met the eligibility criteria. The risk ratio (RRs) of both the primary and secondary outcomes of bilateral rTMS showed non-significant increases compared to unilateral rTMS (RR=1.01, P=0.93; odds ratio [OR]=0.77, P=0.22). Notably, the RR of the primary bilateral rTMS outcome was significantly increased compared to that for sham rTMS (RR=3.43, P=0.0004). The results of our analysis demonstrated that bilateral rTMS was significantly more effective than sham rTMS but not unilateral rTMS in patients with TRD. Thus, bilateral rTMS may not be a useful paradigm for patients with TRD.

Advanced oxidation protein products as a biomarker of cutaneous lupus erythematosus complicated by nephritis: a case-control study

Oxidative stress is involved in the pathogenesis of lupus nephritis (LN). The current study investigated the significance of advanced oxidation protein products (AOPPs) as a biomarker of LN in patients with cutaneous lupus erythematosus. Ninety-two patients who initially presented with systemic lupus erythematosus were divided into the LN- and LN+ groups. Serum AOPP levels were determined, and the association between AOPP levels and LN was investigated in a case-control study. In the LN+ group, patients with higher AOPP levels exhibited higher levels of dsDNA and proteinuria but lower levels of eGFR and complement C3 compared to those in patients with lower AOPP levels. A multivariable logistic regression model showed that the AOPP level was an independent risk factor for LN. The risk of nephritis specifically increased 24% for each 10 μM increase in AOPP (95% confidence interval, 1.166-1.915, P = 0.030). In contrast, neither elevated dsDNA level nor decreased complement C3 level was an independent risk factor for LN. Higher serum AOPP levels were associated with an increased risk of LN. Therefore, future studies are warranted to determine the potential clinical value of this novel biomarker.

Meta-analysis on the efficacy and tolerability of the augmentation of antidepressants with atypical antipsychotics in patients with major depressive disorder

We assessed the efficacy and tolerability of the augmentation of antidepressants (ATDs) with atypical antipsychotics (AAPs) to treat patients with major depressive disorder. A retrograde study to identify relevant patient data included databases of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Database of Abstracts of Reviews of Effects. Data from 17 trials, involving 3807 participants, were identified. The remission rate (RR) and overall response rate (ORR) of adjunctive treatment with AAPs were significantly higher than placebo treatment: RR=1.90 (95%CI=1.61-2.23, z=7.74, P<0.00001) and ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001). We found that the short-term (4 weeks) treatment [ORR=1.70 (95%CI=0.98-2.95, Z=1.89, P=0.06)] was significantly different from the long-term (6-12 weeks) treatment [ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001)]. No significant difference in ORR was observed between groups with or without sedative drugs. The discontinuation rate due to adverse effects was higher for adjunctive treatment with AAPs: ORR=3.32 (95%CI=2.35-4.70, z=6.78, P<0.00001). These results demonstrate that the augmentation of ATDs with AAPs (olanzapine, quetiapine, aripiprazole, and risperidone) was more effective than a placebo in improving response and remission rates, although associated with a higher discontinuation rate due to adverse effects.

Effect of CDH1 gene methylation on transforming growth factor (TGF-β)-induced epithelial-mesenchymal transition in alveolar epithelial cell line A549

The aim of this study was to investigate the specific molecular mechanism of the transforming growth factor β (TGF-β)-induced epithelial-mesenchymal transition in a lung cancer cell line, and to provide new ideas for targeting therapy of lung cancer. A549 cells were treated with different concentrations of TGF-β and 5-aza-deoxycytidine (5-aza-dC). The morphological changes after the intervention were observed. The change in the expression of the epithelial marker E-cadherin (E-cad) was detected by Western blot. The proliferation of A549 cells was measured using the MTT assay. Cell movement and invasion capacity was evaluated with the cell scratch test and invasion test. TGF-β induced A549 cells to transform to a mesenchymal cell morphology and downregulated the expression of E-cad, and 5-aza-dC inhibited this phenomenon. Compared with the control group, the number of transmembrane cells was higher and cell migration was markedly increased in the experimental group with continued culture in the presence of 10 ng/mL TGF-β, showing significant differences (P < 0.05). CDH1 gene methylation is involved in TGF-β-induced epithelial-mesenchymal transition in the alveolar epithelial cell line A549.

Enhanced tumor accumulation and cellular uptake of liposomes modified with ether-bond linked cholesterol derivatives

Novel liposomal formulations based on cholesterol modification had been designed previously by our lab, but we found them with a poor stability and short half-life, especially in blood circulation. The results might be attributed to the hydrolysis of ester linked cholesterol derivatives by esterase in plasma. Thus, in this study, we newly synthesized ether-linked cholesterol derivatives and compared them to other preparations. A comparison with the substrate cholesterol-PEG2000-maleimide showed that ether-linked cholesterol-PEG2000-maleimide could relatively maintain integrity in serum, with only a small mottle emerging on TLC (thin-layer chromatography) plates through the experiment. Then a cell-penetrating peptide TAT was attached to the distal end of CHO-PEG2000 to prepare liposomes and to further evaluate the two cholesterol derivatives. Optimized liposomes (65:35, lipid/cholesterol, molar ratio) composed of 3% CHO-PEG2000 and 3% CHO-PEG2000-TAT showed good stability in 50%FBS (fetal bovine serum). In vitro experiments showed that as incubation time prolonged, ether-linked-TAT LIP showed a 3.67-fold higher uptake amount than ester-linked-TAT LIP. In vivo, ether-linked-TAT LIP accumulated better in tumors and had a 40% higher cellular uptake amount. Altogether, we could conclude that our newly ether-linked cholesterol derivatives possessed better stability especially in blood circulation which led to increased tumor cellular uptake in vitro and in vivo. Our study may offer a better way in cholesterol modification to prepare functionalized liposomes.

Glucose regulates secretion of exogenously expressed insulin from HepG2 cells in vitro and in a mouse model of diabetes mellitus in vivo

Glucose-controlled insulin secretion is a key component of its regulation. Here, we examined whether liver cell secretion of insulin derived from an engineered construct can be regulated by glucose. Adenovirus constructs were designed to express proinsulin or mature insulin containing the conditional binding domain (CBD). This motif binds GRP78 (HSPA5), an endoplasmic reticulum (ER) protein that enables the chimeric hormone to enter into and stay within the ER until glucose regulates its release from the organelle. Infected HepG2 cells expressed proinsulin mRNA and the protein containing the CBD. Immunocytochemistry studies suggested that GRP78 and proinsulin appeared together in the ER of the cell. The amount of hormone released from infected cells varied directly with the ambient concentration of glucose in the media. Glucose-regulated release of the hormone from infected cells was rapid and sustained. Removal of glucose from the cells decreased release of the hormone. In streptozotocin-induced diabetic mice, when infected with adenovirus expressing mature insulin, glucose levels declined. Our data show that glucose regulates release of exogenously expressed insulin from the ER of liver cells. This approach may be useful in devising new ways to treat diabetes mellitus.

Cellular stress response in Eca-109 cells inhibits apoptosis during early exposure to isorhamnetin

The flavonol aglycone isorhamnetin shows anti-proliferative activity in a variety of cancer cells. Previous work, from our laboratory showed that isorhamnetin inhibits the proliferation of human esophageal squamous carcinoma Eca-109 cells in vitro, but only after 72 h of exposure. This led us to propose that isorhamnetin exposure induces a cellular stress response that inhibits the antiproliferative and apoptotic effects of the compound during early exposure. To test this hypothesis, the present study examined the effects of isorhamnetin on Eca-109 cells during the first 72 h of exposure. Cell growth was assessed using the trypan blue exclusion assay, and expression of IκBα, NF-κB/p65, NF-κB/p50, phospho-Akt, Bcl-2, COX-2, Mcl-1, Bax, p53 and Id-1 were analyzed by Western blot. During the first 72 h of exposure, NF-κB/p65 and NF-κB/p50 accumulated in nuclei and expression of COX-2, Bcl-2 and Mcl-1 increased. In contrast, expression of IκBα and Bax fell initially but later increased. Expression of phospho-Akt and p53 showed no detectable change during the first 48 h. Pretreatment with the NF-κB inhibitor MG132 before exposure to isorhamnetin blocked the nuclear accumulation of p50 and p65, thereby inhibiting cell proliferation. These results show that during early exposure of Eca-109 cells to isorhamnetin, the NF-κB signaling pathway is activated and COX-2 expression increases, and this increase in expression partially inhibits isorhamnetin-induced apoptosis. Beyond 72 h of exposure, however, the apoptotic effect of isorhamnetin dominates, leading to inhibition of the NF-κB pathway and of cellular proliferation. These results will need to be taken into account when exploring the use of isorhamnetin against cancer in vivo.

Controlling magnetoelectric coupling by nanoscale phase transformation in strain engineered bismuth ferrite

The magnetoelectric coupling in multiferroic materials is promising for a wide range of applications, yet manipulating magnetic ordering by electric field proves elusive to obtain and difficult to control. In this paper, we explore the prospect of controlling magnetic ordering in misfit strained bismuth ferrite (BiFeO(3), BFO) films, combining theoretical analysis, numerical simulations, and experimental characterizations. Electric field induced transformation from a tetragonal phase to a distorted rhombohedral one in strain engineered BFO films has been identified by thermodynamic analysis, and realized by scanning probe microscopy (SPM) experiment. By breaking the rotational symmetry of a tip-induced electric field as suggested by phase field simulation, the morphology of distorted rhombohedral variants has been delicately controlled and regulated. Such capabilities enable nanoscale control of magnetoelectric coupling in strain engineered BFO films that is difficult to achieve otherwise, as demonstrated by phase field simulations.

Effects of preventive acupuncture on streptozotocin-induced hyperglycemia in rats

BACKGROUND

Diabetes prevention has received increasing attention recently. Clinical and experimental studies showed that acupuncture could produce hypoglycemic effect. However, little is known about the effectiveness of acupuncture in diabetes prevention.

AIM

To investigate the preventive effects of acupuncture on streptozotocin (STZ)-induced hyperglycemia in rats.

METHODS

Hyperglycemia was induced by a single intraperitoneal injection of STZ (60 mg/kg). Rats were randomly divided into six groups (no.=8 each group): control, diabetes, preventive acupuncture plus STZ injection, STZ injection plus therapeutic acupuncture, STZ injection plus preventive and therapeutic acupuncture, and preventive and therapeutic acupuncture control. Body weight, blood glucose, serum insulin, lipid peroxidation, and antioxidant enzymes were measured by routine standard methods. Histological analysis of pancreatic islets was conducted.

RESULTS

Preventive acupuncture significantly relieved hyperglycemia, insulin deficiency, weight loss, and pancreatic islet damage in rats with STZ injection; it also significantly reduced serum lipid peroxidation and enhanced superoxide dismutase in the serum and the pancreas without significantly affecting serum glutathione peroxidase and catalase. Therapeutic acupuncture exhibited a hypoglycemic effect in the late stage, but did not significantly improve other parameters.

CONCLUSIONS

These results indicate that preventive acupuncture is beneficial to the control of STZ-induced hyperglycemia in rats.

Molecular analysis of the coat protein gene of peanut stripe virus from China

Peanut stripe virus (PStV) is one of the most common viruses infecting peanut that causes great economic losses every year. The 3ʹ-terminal 1082 bp of 74 PStV isolates collected from 12 districts of Shandong province, China were sequenced. Their coat protein (CP) genes were 864 bp in length and shared identities of 98.0%~100% and 98.3% ~100% at nt and aa levels. The identities between the CP genes of these isolates and other 36 isolates from the GenBank were 93.5%~100% and 92.0%~100% at nt and aa levels, respectively. PStV isolates can be clustered into two phylogenetic groups. The isolates from United States, mainland China, and Indonesia formed group I and those from Viet Nam, Thailand, and Taiwan formed group II. The PStV isolates in group I can be further classified to two subgroups. The gene flow of PStV populations within a country was frequent, but that between countries was infrequent.

Pharmacokinetics, tissue distribution and excretion study of dl-praeruptorin A of Peucedanum praeruptorum in rats by liquid chromatography tandem mass spectrometry

dl-Praeruptorin A (Pd-Ia), isolated from Chinese traditional herbal medicine Peucedanum praeruptorum Dunn, has been proved to be a novel Ca²+-influx blocker and K+-channel opener, and displayed bright prospects in prevention and therapy of cardiac diseases. The aim of this study was to investigate the pharmacokinetics, tissue distribution and excretion of Pd-Ia in rats following a single intravenous (i.v.) administration. The levels of Pd-Ia in plasma, tissues, bile, urine and feces were measured by a rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The results showed that Pd-Ia was rapidly distributed and then eliminated from rat plasma and manifested linear dynamics in dose range of 5-20 mg/kg. The mean elimination half-life (t(½) of Pd-Ia for 5, 10 and 20 mg/kg dose were 57.46, 60.87 and 59.01 min, respectively. The major distribution tissues of Pd-Ia in rats were spleen, heart and lung, and low polarity enabled Pd-Ia to cross the blood-brain barrier. There was no long-term accumulation of Pd-Ia in rat tissues. Total recoveries of Pd-Ia within 24 h were low (0.097% in bile, 0.120% in urine and 0.009% in feces), which might be resulted from liver first pass effect.

Genetic diversity of Potato virus Y infecting tobacco crops in China

Genetic variability of Potato virus Y (PVY) isolates infecting potato has been characterized but little is known about genetic diversity of PVY isolates infecting tobacco crops. In this study, PVY isolates were collected from major tobacco-growing areas in China and single-lesion isolates were produced by serial inoculation on Chenopodium amaranticolor. Most isolates (88%) caused systemic veinal necrosis symptoms in tobacco. Of these, 16 isolates contained a PVY(O)-like coat protein (CP) and PVY(N)-like helper component proteinase (HC-pro) and, in this respect, were similar to the PVY(N-Wi), PVY(N:O), and PVY-HN2 isolates characterized from potato in Europe, the United States, and China, respectively; two isolates contained a PVY(O)-like HC-pro and a PVY(N)-like CP; another two isolates had recombination junctions in the CP-encoding region. Both the HC-pro and CP of PVY were under negative selection as a whole; however, seven amino acids in HC-pro and six amino acids in CP were under positive selection. Selection pressures differed between the subpopulations of PVY distinguished by phylogenetic analysis of HC-pro and CP sequences. When PVY isolates from potato were included, no host-specific clustering of the PVY isolates was observed in phylogenetic and nucleotide diversity analyses, suggesting frequent spread of PVY isolates between potato and tobacco crops in the field.

+Antisense oligonucleotide targeting survivin inhibits growth by inducing apoptosis in human osteosarcoma cells MG-63

Survivin may play an important role in the development of osteosarcoma. In this study, we chose osteosarcoma cell line MG-63, which highly expressed survivin, to observe the effects of antisense oligonucleotide targeting survivin on the apoptosis induction and proliferation inhibition. It was shown in our results that the apoptosis rate and the proliferation inhibition rate increased significantly in survivin-positive cells MG-63 by using MTT and flow cytometry methods. We found that the growth inhibition rate and apoptosis rate were changed in a dose-dependent way. When the concentration of antisurvivin oligonucleotide was 600 nM, the effects reached the peak. RT-PCR and western-blot methods were used to detect the mRNA and protein expression of survivin in MG-63. We observed that the mRNA and protein expression of survivin reduced after transfected with antisurvivin oligonucleotides at the concentration of 200 nM, 400 nM and 600 nM. At the same time, we found that the mRNA and protein expression of Fas were up-regulated with the concentration of antisurvivin oligonucleotides from 200 nM to 600 nM. It was negative associated with the expression change of survivin. These data suggested that survivin should play an important role in the development of osteosarcoma and the survivin blockaded by using antisurvivin oligonucleotide could inhibit the proliferation and induce apoptosis of osteosarcoma by decreasing the expression of survivin and activate the Fas-mediated apoptosis. Down-regulation of survivin by antisense oligonucleotide might be an effective strategy to the treatment of osteosarcoma and might improve the therapeutic effect.

KEYWORDS

osteosarcoma, Survivin, apoptosis, Fas.

Identification of differentially expressed genes at two key endosperm development stages using two maize inbreds with large and small grain and integration with detected QTL for grain weight

Maize endosperm accounts for more than 80% of the grain weight. Cell division and grain filling are the two key stages for endosperm development. Previous studies showed that gene expression during differential stages in endosperm development is greatly different. However, information on systematic identification and characterization of the differentially expressed genes between the two stages are limited. In this study, suppression subtractive hybridization (SSH) was used to generate four subtracted cDNA libraries for the two stages using two maize inbreds with large and small grain. Totally, 4,784 differentially expressed sequence tags (ESTs) were sequenced and 902 were non-redundant, which consisted of 344 unique ESTs. Among them 192 had high sequence similarity to the GenBank entries and represent diverse of functional categories, such as metabolism, cell growth/division, transcription, signal transduction, protein destination/storage, protein synthesis and others. The expression patterns of 75.7% SSH-derived cDNAs were confirmed by reverse Northern blot and semi-quantitative reverse transcription polymerase chain reaction, and exhibited the similar results (75.0%). Genes differentially expressed between two key stages for the two inbreds were involved in diverse physiological process pathway, which might be responsible for the formation of grain weight. 43.8% (70 of the 160 unique ESTs) of the identified ESTs were assigned to 39 chromosome bins distributed over all ten maize chromosomes. Eleven ESTs were found to co-localize with previous detected QTLs for grain weight, which might be considered as the candidate genes of grain weight for further study.

RACK1, a potential target to decrease morphine reward in mice

Morphine reexposure induces the decrease of receptor for activated C-kinase 1 protein (RACK1) levels in frontal cortex, and the increase of p-ERK (extracellular signal-regulated kinase) levels in mouse frontal cortex, striatum, hippocampus and nucleus accumbens (NAcc). Moreover, RACK1 is associated with the core kinases of the ERK pathway, Raf, MEK, and ERK. The purpose of this study is to investigate the effect of overexpression of RACK1 on the conditioned place preference (CPP) and the level of p-ERK in morphine reexposure mice. Mice were subcutaneously injected with morphine on the 2nd, 4th, 6th, and the 8th day, saline was delivered the next day. After mice showed place preference, RACK1 was administered by intraventricular injection 20 minutes after injection of morphine on the 11th, 13th, 15th, and 17th day. CPP was measured on the 18th day. It was found that morphine reexposured mice showed a decreased RACK1 level in the frontal cortex, striatum and an increased RACK1 level in hippocampus and NAcc, but this effect was reversed after administration of RACK1. In this study we demonstrated that RACK1 decreased p-ERK and erased CPP during reexposure of morphine and there was no an effect in reexposure saline mice. It strongly suggests that RACK1 may play a crucial role in morphine reexposured mice and the RACK1 has the potential to be a remedy to the morphine reward.