Enhanced sensitivity to group II mGlu receptor activation at corticostriatal synapses in mice lacking the familial parkinsonism-linked genes PINK1 or Parkin

An altered glutamatergic input at corticostriatal synapses has been shown in experimental models of Parkinson's disease (PD). In the present work, we analyzed the membrane and synaptic responses of striatal neurons to metabotropic glutamate (mGlu) receptor activation in two different mouse models of inherited PD, linked to mutations in PINK1 or Parkin genes. Both in PINK1 and Parkin knockout ((-/-)) mice, activation of group I mGlu receptors by 3,5-DHPG caused a membrane depolarization coupled to an increase in firing frequency in striatal cholinergic interneurons that was comparable to the response observed in the respective wild-type (WT) interneurons. The sensitivity to group II and III mGlu receptors was tested on cortically-evoked excitatory postsynaptic potentials (EPSPs) recorded from medium spiny neurons (MSNs). Both LY379268 and L-AP4, agonists for group II and III, respectively, had no effect on intrinsic membrane properties, but dose-dependently reduced the amplitude of corticostriatal EPSPs. However, both in PINK1(-/-) and Parkin(-/-) mice, LY379268, but not L-AP4, exhibited a greater potency as compared to WT in depressing EPSP amplitude. Accordingly, the dose-response curve for the response to LY379268 in both knockout mice was shifted leftward. Moreover, consistent with a presynaptic site of action, both LY379268 and L-AP4 increased the paired-pulse ratio either in PINK1(-/-) and Parkin(-/-) or in WT mice. Acute pretreatment with L-dopa did not rescue the enhanced sensitivity to LY379268. Together, these results suggest that the selective increase in sensitivity of striatal group II mGlu receptors represents an adaptive change in mice in which an altered dopamine metabolism has been documented.

Autophagic and apoptotic cell death in amniotic epithelial cells

The aim of this paper is to determine if autophagic cell death is associated with apoptosis and whether it participates in the process of term amniotic rupture. Forty pieces of fresh term amnions, including twenty from a position near the margin of the placentas and twenty from the margin of the naturally ruptured part of the placentas in term gestation were collected, respectively. The amnions were examined by scanning electron microscopy (SEM) and amniotic epithelial (AE) cells were examined by transmission electron microscopy (TEM). Autophagic and apoptotic cell death (PCD) were assayed by laser scanning confocal microscopy (LSCM) or flow cytometry using monodansylcadaverin (MDC) and propidium iodide (PI) stain. BCL(2) and BAX were examined by immunoblotting. Under SEM the amniotic epithelia appeared normal in the position near the placenta. They had an atrophied appearance in the margin of their natural broken parts. In the AE cells PCD was divided into three subtypes by TEM: autophagic cell death with positive stains of MDC and PI; apoptotic cell death; and the mixed type. Quantitative detection showed that there were more death cells, including autophagic and apoptotic, in the AE cells near the ruptured parts than near the placentas. An increased expression of BAX and a decreased expression of BCL(2) protein in the AE cells near the broken margin were observed. Apoptotic and autophagic cell death by the intrinsic pathway are the basic event in the AE cell and they are involved in the cause of membrane rupture of the human amnion in term gestation.

Solubilization and Pharmacokinetic Behaviors of Sodium Cholate/Lecithin-Mixed Micelles Containing Cyclosporine A

The purpose of this study was to investigate the solubilization capacity of sodium cholate/lecithin-mixed micelles and to evaluate the potential of mixed micelles as a carrier of cyclosporine A for intravenous infusion. The mixed micelles were prepared by coprecipitation technique. The formulation components and preparation procedures, which may affect the solubilization of cyclosporine A, were studied. The dilution stability of cyclosporine A-containing mixed micelles was investigated. Pharmacokinetic behaviors of mixed micelles in rabbits after intravenous infusion were compared with Sandimmun. Results showed the strategies to increase the solubility of cyclosporine A include lowering the molar ratio of sodium cholate to lecithin, increasing the concentration of lecithin, and reducing the ionic strength of the dispersion medium and temperature. The largest solubility was found to be 5.42 +/- 0.16 mg/ml. The leakage of mixed micelles in 5% glucose (5.84%) was much less than that in saline solution (36.7%). The relative bioavailability of mixed micelles versus Sandimmun was 112 +/- 20%, and statistical analysis demonstrated both preparations were bioequivalent. Sodium cholate/lecithin-mixed micelles are promising carriers in the intravenous delivery of cyclosporine A, considering their capability of large-scale production and low-toxic property.

Reemergent metal-insulator transitions in manganites exposed with spatial confinement

The metal-insulator transition is characterized as a single peak in the temperature-dependent resistivity measurements; exceptions to this have never been seen in any single crystal material system. We show that by reducing a single crystal manganite thin film to a wire with a width comparable to the mesoscopic phase-separated domains inherent in the material, a second and robust metal-insulator transition peak appears in the resistivity versus temperature measurement. This new observation suggests that spatial confinement is a promising route for the discovery of emergent physical phenomena in complex oxides.

Release of the medial collateral ligament to improve flexion in post-traumatic elbow stiffness

Contracture of the collateral ligaments is considered to be an important factor in post-traumatic stiffness of the elbow. We reviewed the results of isolated release of the medial collateral ligament in a series of 14 patients with post-traumatic loss of elbow flexion treated between 1998 and 2002. There were nine women and five men with a mean age of 45 years (17 to 76). They were reviewed at a mean follow-up of 25 months (9 to 48). The operation was performed through a longitudinal posteromedial incision centred over the ulnar nerve. After decompression of the ulnar nerve, release of the medial collateral ligament was done sequentially starting with the posterior bundle and the transverse component of the ligament, with measurement of the arc of movement after each step. If full flexion was not achieved the posterior half of the anterior bundle of the medial collateral ligament was released.

At the latest follow-up, the mean flexion of the elbow improved significantly from 96° (85° to 115°) pre-operatively to 130° (110° to 150°) at final follow-up (p = 0.001). The mean extension improved significantly from 43° (5° to 90°) pre-operatively to 22° (5° to 40°) at final follow-up (p = 0.003). There was a significant improvement in the functional outcome. The mean Broberg and Morrey score increased from a mean of 54 points (29.5 to 85) pre-operatively to 87 points (57 to 99) at final follow-up (p < 0.001). All the patients had normal elbow stability.

Our results indicate that partial surgical release of the medial collateral ligament is associated with improved range of movement of the elbow in patients with post-traumatic stiffness, but was less effective in controlling pain.

The mitotic checkpoint kinase NEK2A regulates kinetochore microtubule attachment stability

Loss or gain of whole chromosome, the form of chromosome instability commonly associated with cancers is thought to arise from aberrant chromosome segregation during cell division. Chromosome segregation in mitosis is orchestrated by the interaction of kinetochores with spindle microtubules. Our studies show that NEK2A is a kinetochore-associated protein kinase essential for faithful chromosome segregation. However, it was unclear how NEK2A ensures accurate chromosome segregation in mitosis. Here we show that NEK2A-mediated Hec1 (highly expressed in cancer) phosphorylation is essential for faithful kinetochore microtubule attachments in mitosis. Using phospho-specific antibody, our studies show that NEK2A phosphorylates Hec1 at Ser165 during mitosis. Although such phosphorylation is not required for assembly of Hec1 to the kinetochore, expression of non-phosphorylatable mutant Hec1(S165) perturbed chromosome congression and resulted in a dramatic increase in microtubule attachment errors, including syntelic and monotelic attachments. Our in vitro reconstitution experiment demonstrated that Hec1 binds to microtubule in low affinity and phosphorylation by NEK2A, which prevents aberrant kinetochore-microtubule connections in vivo, increases the affinity of the Ndc80 complex for microtubules in vitro. Thus, our studies illustrate a novel regulatory mechanism in which NEK2A kinase operates a faithful chromosome attachment to spindle microtubule, which prevents chromosome instability during cell division.

Sustained expression of hepatocyte nuclear factor-6 leads to loss of pancreatic beta-cells by apoptosis

Hepatocyte nuclear factor-6 (HNF-6) is the ONECUT-homeodomain transcription factor that is enriched in liver and also present in pancreas and central nervous system. It is expressed in the pancreatic bud at E10.5. In adult pancreas, its expression is restricted to the exocrine pancreas and duct cells. Since duct cells are thought to be precursors of endocrine cells and HNF-6 is involved in the regulation of the expression of HNF-4alpha and -1beta, genes that cause maturity onset diabetes of the young (MODY), we hypothesized that the sustained expression of HNF-6 would affect beta-cell function. We generated transgenic mice over-expressing human HNF-6 using the mouse insulin I promoter (MIP). We obtained one female founder in which the transgene had been incorporated into two sites; the chromosome (Ch) 14 and the X chromosome. The integration site of the latter was within centromeric heterochromatin and the transgene was inactivated. Studies on mice in which the transgene was integrated into Ch14 showed beta-cell specific defects functionally and pathologically. The insulin secretory response to glucose and arginine in the in situ-perfused pancreas was also significantly impaired in these mice. Immunohistochemical analysis revealed that the islets were smaller and had an abnormal architecture with an inverted ratio of alpha- and beta-cells resulting from beta-cell loss to 30% by 6-wk of age. The decreased number of beta-cells was quantified first time by fluorescent activated cell sorting using entire pancreata from the transgenic mice crossed with MIP-green fluorescent protein (GFP) mice. This severe loss of beta-cells involved programmed cell death.

No association of the POLI Thr706Ala polymorphism with the risk of cervical carcinoma

OBJECTIVE

To investigate the association of repair gene POLI genetic polymorphisms with cervical carcinoma.

MATERIALS AND METHODS

Four hundred sixty one cervical carcinoma patients and 628 normal women were randomly selected for this study. Single nucleotide polymorphisms (SNPs) (POLI Thr706Ala) were genotyped, and the epidemiological risk factor was assessed.

RESULTS

Compared with the POLI Thr706Thr genotype, neither POLI Thr706Ala nor POLI Ala706Ala elevated or decreased the risk of cervical carcinoma or cervical squamous cell carcinoma [ORs and 95% CIs 1.25(0.97-1.61), 1.11(0.67-1.83), 1.22(0.94-1.58), 1.06(0.63-1.78), respectively]. When analyzing the risk of the POLI Thr706Ala variant genotype for cervical carcinoma in different histological types or HPV infection status, very similar risk factors were observed for the squamous cell carcinoma group or the HPV positive group to the overall carcinoma. Regardless of sexual or reproductive histories, patients with the POLI Thr706Ala or POLI Ala706Ala genotype showed a significantly increased risk of cervical carcinoma.

CONCLUSION

The POLI Thr706Ala genotype was not associated with cervical carcinoma in a Chinese population, but we cannot exclude the possibility that the POLI polymorphism might be associated with sexual and reproductive history.

Expression of complement regulatory proteins in accommodated xenografts induced by anti-alpha-Gal IgG1 in a rat-to-mouse model

Anti-graft antibodies are often associated with graft rejection. Under special conditions, grafts continue to function normally even in the presence of anti-graft antibodies and complement. This condition is termed accommodation. We developed a xenograft accommodation model in which baby Lewis rat hearts are transplanted into Rag/GT-deficient mice, and accommodation is induced by repeated i.v. injections of low-dose anti-alpha-Gal IgG(1). The accommodated grafts survived a bolus dose of anti-alpha-Gal IgG(1), while freshly transplanted second grafts were rejected. To study the mechanism of anti-alpha-Gal IgG(1)-mediated accommodation, both real-time PCR and immunohistochemical staining revealed elevated expression of DAF, Crry and CD59 in the accommodated grafts. In vitro exposure of rat endothelial cells to anti-alpha-Gal IgG(1) also induced the up-regulation of DAF, Crry and CD59, as revealed by Western blot analyses, and was associated with an acquired resistance to antibody and complement-mediated lysis in vitro. Collectively, these studies suggest that the up-regulation of complement regulatory proteins may abrogate complement-mediated rejection and permit the development of xenograft accommodation.

A comparison of cardiovascular disease risk factor biomarkers in African Americans and Yoruba Nigerians

OBJECTIVE

Classical risk factors for coronary artery disease are changing in the developing world while rates of cardiovascular disease are increasing in these populations. Newer risk factors have been identified for cardiovascular disease, but these have been rarely examined in elderly populations and not those of developing countries.

METHODS

This study was a cross-sectional comparison from a longitudinal, observational, epidemiologic study in which participants are interviewed at three-year intervals. The sample included 1510 African Americans from Indianapolis, Indiana, and 1254 Yoruba from Ibadan, Nigeria. We compared anthropomorphic measurements; biomarkers of endothelial dysfunction (plasminogen activator inhibitor type 1 [PAI-1 and E-selectin), inflammation (C-reactive protein), and lipid oxidation (8-isoprostane); and levels of lipids, homocysteine, folate, and vitamin B12.

RESULTS

Cholesterol, triglycerides, and low-density lipoprotein cholesterol levels were higher in African Americans. For markers of endothelial dysfunction, E-selectin and homocysteine differed between men, and PAI-1 was higher in the Yoruba. C-reactive protein differed only in women, but 8-isoprostane was higher in the Yoruba.

CONCLUSION

Higher lipid levels in African Americans are consistent with their Western diet and lifestyle. Oxidative stress appears to be higher in the Yoruba than in African Americans, which may be secondary to dietary differences. Whether these differences in classical and emerging risk factors account for the different rates of cardiovascular disease, dementia, or other morbidities in these two populations remains to be determined.

Interleukin-18 gene polymorphisms and haplotypes in patients with oral lichen planus: a study in an ethnic Chinese cohort

Interleukin (IL)-18, a proinflammatory cytokine, induces T-helper 1 differentiation and cytotoxic T-lymphocyte functions, both of which have been proposed in the pathogenesis of oral lichen planus (OLP) - an oral disease resembles oral mucosal graft-versus-host disease (GVHD) both clinically and histologically. The aim of this study was to evaluate the association of single nucleotide polymorphisms (SNPs) in the IL18 gene on the chromosome 11q22 in patients with OLP. Four SNPs of the IL18 gene at positions -137G/C (rs187238), -607C/A (rs1946518), -656G/T (rs1946519), and 1248A/G (rs189667) were analyzed in 151 patients with OLP and 143 normal controls using polymerase chain reaction-sequence-specific primers method, and the serum level of IL-18 protein was determined by enzyme-linked immunosorbent assay (ELISA). The data revealed that there is a significant difference in IL18-607 genotype distributions between the patient group and the control group (P < 0.001), and the polymorphism -137G/C also appears to be statistically associated with the more severe erosive subtype (eOLP) (P = 0.023). The identified polymorphisms at the IL-18 promoter region (i.e. -137GG) are likely to exert positive effect on the production of IL-18 protein in OLP, as detected by ELISA. Using phase software, four haplotypes were deduced from the two polymorphisms -607C/A and -137G/C, named haplotypes I to IV, and the haplotypes I, II, and IV are significantly associated with OLP (P < 0.001). Our data suggest that the identified IL18 polymorphisms may be associated with the pathogenesis of OLP in this Chinese cohort by upregulation of IL-18 production in vivo.

Meta-analysis: The utility and safety of heparin in the treatment of active ulcerative colitis

BACKGROUND

The use of heparin for the treatment of ulcerative colitis has been evaluated in several open and controlled trials, with varying outcomes.

AIM

To evaluate the efficacy and safety of heparin as supplemental therapy compared with conventional therapy in patients with ulcerative colitis.

METHODS

All randomized trials comparing heparin supplementation to conventional therapy were included from electronic databases. Statistical analysis was performed with review manager 4.2.8 (The Cochrane Collaboration, Oxford, UK). Sub-analysis and sensitivity analysis were also performed.

RESULTS

Eight randomized-controlled trials, investigating a total of 454 participants, met the inclusion criteria. The odds ratio (OR) for the efficacy of heparin supplementation vs. conventional therapy was 0.78 (95% CI = 0.50-1.21). Few serious adverse events were observed. The OR for the efficacy of unfractionated heparin and low-molecular-weight heparin vs. conventional therapy was 0.26 (95% CI = 0.07-0.93) and 0.92 (95% CI = 0.57-1.47), respectively. The OR for the efficacy of heparin vs. conventional therapy with placebo was 0.87 (95% CI = 0.53-1.44).

CONCLUSIONS

Our meta-analysis suggests that administration of heparin in patients with ulcerative colitis is safe, but no additive benefit over conventional therapy is indicated.

Forced expression of a constitutively active form of Stat3 in mouse epidermis enhances malignant progression of skin tumors induced by two-stage carcinogenesis

Recently, our laboratory demonstrated that Stat3 is required for the de novo development of chemically-induced skin tumors. We have further investigated the role of Stat3 in epithelial carcinogenesis using mice in which the expression of a constitutively active/dimerized form of Stat3 (Stat3C) is targeted to the proliferative compartment of epidermis (referred to as K5.Stat3C transgenic mice). Keratinocytes from K5.Stat3C mice showed increased survival following exposure to 7,12-dimethylbenz[a]anthracene (DMBA) and enhanced proliferation following exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA). In two-stage chemical carcinogenesis experiments using DMBA as the tumor initiator and TPA as the promoter, K5.Stat3C mice developed skin tumors with a shorter latency and in much greater number compared to non-transgenic littermates. Remarkably, 100% of the skin tumors that developed in K5.Stat3C transgenic mice bypassed the premalignant stage and were initially diagnosed as carcinoma in situ which rapidly progressed to squamous cell carcinoma (SCC). These tumors were highly vascularized, poorly differentiated and invasive and loss of expression of K10, filaggrin and E-cadherin was observed by 20 weeks. Finally, overexpression of Stat3C in a papilloma cell line led to enhanced cell migration and enhanced invasion through Matrigel in both the absence and presence of growth factors. In addition to its critical role in early stages of epithelial carcinogenesis, the current study reveals a novel role for Stat3 in driving malignant progression of skin tumors in vivo.

The cell cycle regulation of anti-cancer bioactive peptide (ACBP) on gastric cancer cell lines

15087

Background: Anti-cancer bioactive peptide (ACBP) was extracted from the spleen of the goat suffered immune inducement by immunoreaction, supercentrifuge and ultra-filtration. Our previous studies have identified ACBP had significantly inhibited the growth of the human gastric cancer cell lines BGC-823 and MGC-803, the human rhinopharyngocele cell line CNE and the leukemic cell line. The in vivo experiments showed ACBP could dramatically repress the growth of tumor, and had few side-effects in the long-term toxic experiments. In clinical trials, ACBP could enhance the survival and life quality of the patients with advanced gastric cancer. In this study, we will explore the influence and mechanism of the effect of ACBP on cell cycle using human gastric cancer cell lines BGC-823 and MGC-803. Methods: Human gastric cancer cell lines BGC-823 and MGC-803 were cultured with different concentrations (10–25 ug/ml) of ACBP. The MTT method was employed to measure the growth inhibition rates of the cells with different concentrations of ACBP; the morphological changes were observed under the light microscope; the semi-quantitative RT-PCR was used to assay the changes of mRNA for p16,p21,p27,c-myc,cyclin D1,bax,bcl-2 gene. Results: Different concentrations of ACBP in the range of 10.0–25.0 μg/ml could inhibit the growth of BGC-823 and MGC-803 cell and such effect was both concentration and time dependent. 25.0 μg/ml ACBP had an inhibition rate (IR) of 84.4%, 72.3% and a median concentration (IC50) of 17.86 μg/ml, 13.16 ug/ml. After ACBP treatment, the cells showed typical apoptotic changes under the light microscope. On RT-PCR, the expressions of p16,p21,p27,bax mRNA in the two cell lines were markedly increased after ACBP treatment. On the contrary, the expression of c-myc,cyclin D1,bcl-2 mRNA in the two cell lines were obviously decreased after ACBP treatment. Conclusion: ACBP had markedly repressed the growth of BGC-823 and MGC-803 cell lines through inducing the cellular apoptosis. The possible mechanism is ACBP affects the cell cycle molecules expression including p16,p21,p27,cyclin D1 and regulate c-myc,bcl-2 and bax to induce apoptosis.

No significant financial relationships to disclose.

Pemetrexed plus cetuximab in patients (pts) with recurrent non-small cell lung cancer (NSCLC): A phase I-IIa dose-ranging study from the Hoosier Oncology Group

7698

Background: Both pemetrexed (P) and cetuximab (C) have single agent activity in NSCLC, non-overlapping toxicities and different mechanisms of action, making the combination of P and C an attractive option to evaluate. This study evaluates the feasibility of combining these agents, and tests the activity and toxicity of this regimen in pts with recurrent NSCLC. Methods: Eligible pts had stage IIIB/IV NSCLC, previously treated ≥ 1 prior platinum containing regimen, PS 0–1. Prior use of EGFR tyrosine kinase inhibitors was permitted. The phase I portion determined the MTD (Bedano Proc ASCO et al., 2006). The primary endpoint of the phase II portion was to estimate TTP using Kaplan-Meier analysis (5% alpha, 80% beta), requiring 25 pts to demonstrate a TTP of ≥ 24 weeks vs. historical control of 12 weeks. Following a loading dose of C at 400 mg/m2 on week 1, pts received P at 750 mg/m2 iv q3wks and C at 250 mg/m2 iv weekly. Cycles were repeated every 21 days. After completing at least 4 cycles, pts with non-progressive disease (PD) were allowed to continue C alone until PD. Results: Eligible and treated phase II pts (n=23) received a median of 4 cycles (range 1–12). Pt characteristics: M:F 57%:43%; median age 64 (range 43–80), stage IIIB: IV 17%:83%; adeno:squamous cell 61%:30%; smoking status: current/former/never: 29%/62%/10%. Prior regimens, median 2 (range 1–6). G3/4/5 toxicities included: 4.3% neutropenia, 13% infection, 4.3% hemorrhage, 22% skin. There were no G3/4 episodes of anemia, TCP, febrile neutropenia, liver toxicity or diarrhea. Response data was available for 18 patients. Partial responses were seen in 2 pts (8.7 %), SD in 8 patients (34.8%). Median TTP was 25 weeks. Conclusion: It is feasible and safe to combine P at 750 mg/m2 every 21 days and C at 400 mg/m2 week 1 and 250 mg/m2 weekly thereafter. This combination resulted in longer TTP when compared with historical controls of P at 500 mg/m2 alone.

No significant financial relationships to disclose.

Paeoniflorin inhibits TGF-beta1-mediated collagen production by Schistosoma japonicum soluble egg antigen in vitro

The main pathological characteristics of hepatic fibrosis in schistosomiasis are the proliferation of hepatic stellate cells (HSCs) and the deposition of collagen type I (Col I) and collagen type III (Col III). Transforming growth factor beta-1 (TGF-beta1) plays an important role in hepatic fibrosis. Paeoniflorin (PAE) has been reported to have immunoregulatory effects; however, the mechanism of its anti-hepatic fibrosis in S. japonicum has not been elucidated. In the present study, we found that mouse peritoneal macrophages (PMphis) stimulated by soluble egg antigen (SEA) of S. japonicum could secrete TGF-beta1, and the TGF-beta1 in the peritoneal macrophage-conditioned medium (PMCM) could induce proliferation of HSCs and secretion of Col I and III. We selected PMCM at 1 : 2 dilution as the optimum PMCM (OPMCM). Then we treated HSCs pre-incubated with OPMCM with PAE, and found that the inhibition of HSC proliferation or Col I and III production were closely correlated with the concentration of PAE. Further investigation found that PAE significantly decreased the Smad3 transcription and phosphorylation in HSCs stimulated by OPMCM. In conclusion, SEA plays a key role in hepatic fibrosis by inducing TGF-beta1 from PMphis. PAE can exert anti-fibrogenic effects by inhibiting HSCs proliferation and down-regulating Smad3 expression and phosphorylation through TGF-beta1 signalling.