Tolerance, toxicity and transport of Cd and Zn in Populus trichocarpa

Metal inputs to terrestrial ecosystems are of great concern due their toxicity to biota, especially for elements with no biological function such as cadmium. Fast-growing trees such as poplars may have potential in phytoremediation schemes. We assessed accumulation, metal partitioning, gene expression (Pt-HMA4) and overall tolerance to, and interaction between, cadmium (Cd) and zinc (Zn) in Populus trichocarpa ‘Trichobel’. We predicted that Zn would have an antagonistic effect in Cd accumulation and anticipated some level of tolerance to these metals. Poplars were grown in sandy substrate under different metal applications, ranging from 1 to 243 mg kg−1 Cd; or 30 to 7290 mg kg−1 Zn; and also two combined treatments: 27 mg kg−1 Cd with 90 or 270 mg kg−1 Zn. Growth parameters and metal contents in shoots and roots were determined. Transcriptional levels of the Pt-HMA4 gene were assessed in roots and leaves. P. trichocarpa showed a surprisingly high tolerance to Cd, with root biomass being affected only at the highest doses applied. Metals accumulated mainly in roots (up to 6537 mg kg−1 Cd and 21,500 mg kg-1 Zn), root-to-shoot translocation peaked at the 9 mg kg−1 dose for Cd (41%) and 90 mg kg−1 for Zn (40%). At high Cd/Zn applications, expression of Pt-HMA4 in roots decreased significantly. Contrary to the initial presumption, Zn addition increased Cd uptake, reaching hyperaccumulator-like concentrations in shoots (≥100 mg kg−1 Cd). Differential root-to-shoot partitioning has a major role in Cd tolerance in P. trichocarpa; partly by down-regulating the Pt-HMA4 gene in roots. Zn addition promoted high Cd uptake without any detriment to plant growth. P. trichocarpa was tolerant to extreme Cd concentrations, offering a great potential to be used in phytoremediation techniques for stabilization/extraction of Cd from soils contaminated by both Cd and Zn

Utility of neutrophil Fcgamma receptor I (CD64) index as a biomarker for mucosal inflammation in pediatric Crohn\u27s disease

BACKGROUND: Neutrophil expression of the Fcgamma receptor I (CD64) is upregulated in adult patients with clinically active inflammatory bowel disease (IBD). We tested the relationship of CD64 with mucosal inflammation and clinical relapse in pediatric Crohn\u27s disease (CD). METHODS: In a cohort of 208 newly diagnosed CD and 43 non-IBD controls, ileal expression of FcgammaRI/S100A9 was determined by RNA sequencing from biopsies obtained at ileocolonoscopy. In a second cohort, we tested for the peripheral blood polymorphonuclear neutrophil (PMN) CD64 index from 26 newly diagnosed CD, 30 non-IBD controls, and 83 children with established CD. RESULTS: Ileal FcgammaRIA mRNA expression was significantly elevated in CD at diagnosis compared with non-IBD controls (P \u3c 0.001), and correlated with ileal S100A9 (calprotectin) expression (r = 0.83, P \u3c 0.001). The median (range) PMN CD64 index for newly diagnosed CD was 2.3 (0.74-9.3) compared with 0.76 (0.39-1.2) for non-IBD controls (P \u3c 0.001) with 96% sensitivity and 90% specificity at the cut point of 1.0. The PMN CD64 index significantly correlated with mucosal injury as measured by the simple endoscopic score for CD (r = 0.62, P \u3c 0.001). Patients with CD in clinical remission receiving maintenance therapy with a PMN CD64 index1.0 (P \u3c 0.01). CONCLUSIONS: An elevated PMN CD64 index is associated with both mucosal inflammation and an increased risk for clinical relapse in pediatric CD. The PMN CD64 index is a reliable marker for sustained remission in patients with CD receiving maintenance therapy

The Cytoplasmic Domain of MUC1 Induces Hyperplasia in the Mammary Gland and Correlates with Nuclear Accumulation of β-Catenin

MUC1 is an oncoprotein that is overexpressed in up to 90% of breast carcinomas. A previous in vitro study by our group demonstrated that the cytoplasmic domain of MUC1 (MUC1-CD), the minimal functional unit of MUC1, contributes to the malignant phenotype in cells by binding directly to β-catenin and protecting β-catenin from GSK3β-induced degradation. To understand the in vivo role of MUC1-CD in breast development, we generated a MUC1-CD transgenic mouse model under the control of the MMTV promoter in a C57BL/6J background, which is more resistant to breast tumor. We show that the expression of MUC1-CD in luminal epithelial cells of the mammary gland induced a hyperplasia phenotype characterized by the development of hyper-branching and extensive lobuloalveoli in transgenic mice. In addition to this hyperplasia, there was a marked increase in cellular proliferation in the mouse mammary gland. We further show that MUC1-CD induces nuclear localization of β-catenin, which is associated with a significant increase of β-catenin activity, as shown by the elevated expression of cyclin D1 and c-Myc in MMTV-MUC1-CD mice. Consistent with this finding, we observed that overexpression of MUC1-C is associated with β-catenin nuclear localization in tumor tissues and increased expression of Cyclin D1 and c-Myc in breast carcinoma specimens. Collectively, our data indicate a critical role for MUC1-CD in the development of mammary gland preneoplasia and tumorigenesis, suggesting MUC1-CD as a potential target for the diagnosis and chemoprevention of human breast cancer

Mice Expressing Low Levels of CalDAG-GEFI Exhibit Markedly Impaired Platelet Activation With Minor Impact on HemostasisHighlights

OBJECTIVE: The tight regulation of platelet adhesiveness, mediated by the αIIbβ3 integrin, is critical for hemostasis and prevention of thrombosis. We recently demonstrated that integrin affinity in platelets is controlled by the guanine nucleotide exchange factor, CalDAG-GEFI (CD-GEFI), and its target, RAP1. In this study, we investigated whether low-level expression of CD-GEFI leads to protection from thrombosis without pathological bleeding in mice. APPROACH AND RESULTS: Cdg1(low) mice were generated by knockin of human CD-GEFI cDNA into the mouse Cdg1 locus. CD-GEFI expression in platelets from Cdg1(low) mice was reduced by ≈90% when compared with controls. Activation of RAP1 and αIIbβ3 was abolished at low agonist concentrations and partially inhibited at high agonist concentrations in Cdg1(low) platelets. Consistently, the aggregation response of Cdg1(low) platelets was weaker than that of wild-type platelets, but more efficient than that observed in Cdg1(-/-) platelets. Importantly, Cdg1(low) mice were strongly protected from arterial and immune complex-mediated thrombosis, with only minimal impact on primary hemostasis. CONCLUSIONS: Together, our studies suggest the partial inhibition of CD-GEFI function as a powerful new approach to safely prevent thrombotic complications

Effect of cadmium on the defense response of Pacific oyster Crassostrea gigas to Listonella anguillarum challenge

Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The activities of several important defensive enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), Na+, K+ -ATPase in gills and hepatopancreas, and phenoloxidase-like (POL) enzyme in hemolymph were assayed. In addition, the expression levels of several genes, including heat shock protein 90 (HSP90), metallothionein (MT), and bactericidal/permeability increasing (BPI) protein were quantified by fluorescent quantitative PCR. The enzyme activities of SOD, ACP, POL, and GPx in hepatopancreas, and the expression of HSP90 were down-regulated, whereas GPx activity in the gill, Na+, K+-ATPase activities in both tissues, and MT expression was increased in Cdexposed oysters post L. anguillarum challenge. However, BPI expression was not significantly altered by co-stress of L. anguillarum infection and cadmium exposure. Our results suggest that cadmium exposure alters the oysters' immune responses and energy metabolism following vibrio infection.Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The activities of several important defensive enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), Na+, K+ -ATPase in gills and hepatopancreas, and phenoloxidase-like (POL) enzyme in hemolymph were assayed. In addition, the expression levels of several genes, including heat shock protein 90 (HSP90), metallothionein (MT), and bactericidal/permeability increasing (BPI) protein were quantified by fluorescent quantitative PCR. The enzyme activities of SOD, ACP, POL, and GPx in hepatopancreas, and the expression of HSP90 were down-regulated, whereas GPx activity in the gill, Na+, K+-ATPase activities in both tissues, and MT expression was increased in Cdexposed oysters post L. anguillarum challenge. However, BPI expression was not significantly altered by co-stress of L. anguillarum infection and cadmium exposure. Our results suggest that cadmium exposure alters the oysters' immune responses and energy metabolism following vibrio infection

Protective Effects of Tetrahydrocurcumin and Curcumin against Doxorubicin and Cadmium-Induced Cytotoxicity in Chang Liver Cells

Purpose: To investigate the cytoprotective effect of tetrahydrocurcumin, (THC) and curcumin (CUR) on cytotoxicity induced by doxorubicin and cadmium in Chang liver cells.Methods: Cytotoxicity was determined by sulforhodamine B assay. The expression of nuclear  factorerythroid- 2-related factor 2 (Nrf2) Nrf2 regulated  cytoprotecetive enzymes, glutamylcysteine ligase catalytic subunit (GCLC) and NADP (H): quinone oxidoreductase1 (NQO1) was determined by Western blot  analysis. Nuclear translocation of Nrf-2 was analyzed by immunofluorescence method. The level of superoxide formation was assayed by chemiluminescence  method.Results: Treatment with THC or CUR significantly induced GCLC and NQO1 expression and the nuclear translocation of Nrf2. Exposure to doxorubicin (DOX) or Cd for 24 h induced cell death of about 50 %.  However, pre-treatment with THC or CUR (1 or 6 μM) for 24 h significantly increased cell survival to 80 or 90 %,  respectively (p < 0.05). Similar pre-treatment with THC or CUR significantly protected against Cd-induced cell death by a level of 80 and 85 %, respectively (p < 0.05). The cytoprotective effect of these compounds was associated with suppressed DOX- and Cd-induced superoxide formation and induction of GCLC and NQO1 expression.Conclusions: THC mediates its effects by activation of Nrf2 and its regulated enzymes, GCLC and NQO1. Induction of GCLC, NQO1 protein expression and suppression of superoxide are associated with the cytoprotective effect.Keywords: Chang hepatocyte, Curcumin, Tetrahydrocurcumin, Cytoprotection, Doxorubicin, Cadmiu

Tolllike receptor 4 (TLR4) polymorphisms in Tunisian patients with Crohn's disease: genotype-phenotype correlation

<p>Abstract</p> <p>Background</p> <p>The immune responses to bacterial products through the pattern recognition receptor (PRR) play a pivotal role in pathogenesis of Crohn's disease. A recent study described an association between CD and some gene coding for bacterial receptor like NOD2/CARD15 gene and TLR4. In this study, we sought to determine whether TLR4 gene was associated with Crohn's disease (CD) among the Tunisian population and its correlation with clinical manifestation of the disease.</p> <p>Methods</p> <p>90 patients with CD and 80 healthy individuals are genotyped for the <it>Asp299Gly </it>and <it>Thr399Ile </it>polymorphisms by restriction fragment length polymorphism analysis.</p> <p>Results</p> <p>The allele and genotype frequency of the TLR4 polymorphisms did not differ between patients and controls. The genotype-phenotype correlation permitted to show that the <it>Thr399Ile </it>polymorphism was associated with early onset disease.</p> <p>Conclusion</p> <p>this study reported the absence of association between CD and TLR4 gene in the Tunisian population, but this gene could play a role in clinical expression of the disease.</p

Characterization of gene and protein marker expression by human dental pulp stem cells

Abstract only availableNeurodegenerative diseases result from deterioration of neurons or their myelin sheath that over time leads to brain dysfunction and premature death. Cells of the brain and spinal cord do not readily regenerate therefore excessive damage can be devastating. Our lab focuses on stem cell-based therapies for brain disorders. Previous studies indicate the potential of stem cells for use in therapies to treat neurodegenerative disorders. In particular, my lab project deals with dental pulp mesenchymal stem cells (DPMSCs) that are currently being investigated due to their ability to differentiate into multiple cell types, including neural cells. Our DPMSCs are composed of populations of mesenchymal stem cells harvested from normal human third molars (wisdom teeth). The initial goal of my research is to assess the variation of marker expression by the dental pulp mesenchymal stem cells to describe their developmental potentials, particularly neuronal development since neurons are the functional unit of the brain. Our results identified expression of neuronal-specific markers (indicative of neuronal precursors and mature neurons) at the gene and protein level by the DPMSCs specifically, we observed expression of nestin, β-III tubulin, and GFAP as well as the MSC markers CD 90, CD 73 and CD 44. Based on these findings, we propose that human DPMSCs may possess the capabilities necessary for therapeutic treatment of neurodegenerative disorders. In future experiments, we plan to perform cell transplantations into mouse models with neurodegenerative disorders. Our results are very significant because they could lead to cures for serious CNS disorders.NSF-REU Program in Biological Sciences & Biochemistr

Canine Mammary Neoplasia Induces Variations in the Peripheral Blood Levels of CD20, CD45RA, and CD99

The idea of using tumour biomarkers as diagnostic tools is progressively increasing. Of these, serum biomarkers are of particular interest, as they can provide rapid results. In the present study, serum samples from 26 bitches diagnosed with mammary tumours, plus 4 healthy bitches, were obtained. The samples were analysed using CD antibody microarrays targeting 90 CD surface markers and 56 cytokines/chemokines. A total of five CD proteins, namely CD20, CD45RA, CD53, CD59, and CD99, were selected and further analysed, utilizing immunoblotting techniques to validate the microarray results. CD45RA showed a significantly lower abundance in the serum samples from the bitches carrying mammary neoplasia in comparison to the healthy animals. Regarding CD99, the serum samples from the neoplastic bitches showed it in a significantly higher abundance than those from the healthy patients. Finally, CD20 showed a significantly higher abundance in bitches carrying a malignant mammary tumour in comparison to healthy patients, but no differential expression between malignant and benign tumours was observed. According to these results, both CD99 and CD45RA are indicators of mammary tumour presence, but without distinguishing between malignant and benign