Methodological Validation of Sedimentation Velocity Analytical Ultracentrifugation Method for Adeno-Associated Virus and Collaborative Calibration of System Suitability Substance.

Currently, adeno-associated virus (AAV) is one of the primary gene delivery vectors in gene therapy, facilitating long-term in vivo gene expression. Despite being imperative, it is incredibly challenging to precisely assess AAV particle distribution according to the sedimentation coefficient and identify impurities related to capsid structures. This study performed the systematic methodological validation of quantifying the AAV empty and full capsid ratio. This includes specificity, accuracy, precision, linearity, and parameter variables involving the sedimentation velocity analytical ultracentrifugation (SV-AUC) method. Specifically, SV-AUC differentiated among the empty, partial, full, and high sedimentation coefficient substance (HSCS) AAV particles while evaluating their sedimentation heterogeneity. The intermediate precision analysis of HE (high percentage of empty capsid) and HF (high percentage of full capsid) samples revealed that the specific species percentage, such as empty or full, was more significant than 50%. Moreover, the relative standard deviation (RSD) could be within 5%. Even for empty or partially less than 15%, the RSD could be within 10%. The accuracy recovery rates of empty capsid were between 103.9% and 108.7% across three different mixtures. When the measured percentage of specific species was more significant than 14%, the recovery rate was between 77.9% and 106.6%. Linearity analysis revealed an excellent linear correlation between the empty, partial, and full in the HE samples. The AAV samples with as low as 7.4 × 1011 cp/mL AAV could be accurately quantified with SV-AUC. The parameter variable analyses revealed that variations in cell alignment significantly affected the overall results. Still, the detection wavelength of 235 nm slightly influenced the empty, partial, and full percentages. Minor detection wavelength changes showed no impact on the sedimentation coefficient of these species. However, the temperature affected the measured sedimentation coefficient. These results validated the SV-AUC method to quantify AAV. This study provides solutions to AAV empty and full capsid ratio quantification challenges and the subsequent basis for calibrating the AAV empty capsid system suitability substance. Because of the AAV structure and potential variability complexity in detection, we jointly calibrated empty capsid system suitability substance with three laboratories to accurately detect the quantitative AAV empty and full capsid ratio. The empty capsid system suitability substance could be used as an external reference to measure the performance of the instrument. The results could be compared with multiple QC (quality control) laboratories based on the AAV vector and calibration accuracy. This is crucial for AUC to be used for QC release and promote gene therapy research worldwide.

Generation and utilization of endostatin-sensitive cell lines for assessing the biological activity of endostatin.

Recombinant proteins are gaining increasing popularity for treating human diseases. The clinical effectiveness of recombinant proteins is directly related to their biological activity, which is an important indicator in drug development and quality control. However, certain recombinant proteins have unclear or complex signal pathways, making detecting their activity in vitro difficult. For instance, recombinant human endostatin (endostatin), a new antitumor drug developed in China, lacks a sensitive and stable assay for its biological activity since being market approval. To address this issue, we performed a genome-wide screening of immortalized human umbilical vein endothelial cells (HUVECs) using a CRISPR/Cas9 knockout library containing 20,000 targeted genes. We identified two potential endostatin-resistant genes, NEPSPP and UTS2, and successfully constructed a highly sensitive cell line, HUVEC-UTS2-3#, by knocking down the UTS2 gene. Based on the optimized parameters of HUVEC-UTS2-3# cells, we established a new method for detecting the biological activity of endostatin. The method was validated, and it produced results consistent with primary HUVEC cells but with higher sensitivity and more stable data. The use of gene-editing technology provides a novel solution for detecting the biological activity of recombinant proteins that other methods cannot detect.

Estimating the dietary exposure and risk of persistent organic pollutants in China: A national analysis.

Substantial heterogeneities have been found in previous estimations of the risk from dietary exposures to persistent organic pollutants (POPs) in China, mainly due to spatiotemporal variations. To comprehensively evaluate the dietary risks of POPs listed in the Stockholm Convention, more than 27,580 data records from 753 reports published over the last three decades were examined. Respectively, for various food categories, the results obtained for the range of mean concentrations of POPs are as follows: total dichlorodiphenyltrichloroethanes (DDTs: 1.4-27.1 µg/kg), hexachlorocyclohexanes (HCHs: 1.8-29.3 µg/kg), polybrominated diphenyl ethers (PBDEs: 0.046-2.82 µg/kg), polychorinated biphenyls (PCBs: 0.05-7.57 µg/kg), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD&Fs: 2.9-210 pg toxic equivalent (TEQ)/kg), perfluorooctanoic acid (PFOA: 0.02-0.97 µg/kg), perfluoroctane sulfonate (PFOS: 0.00082-2.76 µg/kg) and short-chain chlorinated paraffins (SCCPs: 64-348.92 µg/kg). Temporal decreasing trends were observed for DDTs, HCHs, PBDEs, PCDD&Fs, and PFOA, with no significant change for other POPs. Meanwhile, the estimated daily intake for adults were 75.2 ± 43.6 ng/kg/day for DDTs, 123 ± 87 ng/kg/day for HCHs, 0.37 ± 0.17 pg TEQ/kg/day for PCDD&Fs, 17.8 ± 9.5 ng/kg/day for PCBs, 3.3 ± 1.8 ng/kg/day for PBDEs, 3.6 ± 1.9 ng/kg/day for PFOA, 3.3 ± 2.0 ng/kg/day for PFOS, and 2.5 ± 1.6 µg/kg/day for SCCPs. Furthermore, non-carcinogenic risks were the highest for PCBs (0.89) and PCDD&Fs (0.53), followed by PFOA (0.18), PFOS (0.17), HCHs (0.062), SCCPs (0.025), DDTs (0.0075), and PBDEs (0.00047). These findings illustrated that exposure to POPs declined due to the control policies implemented in China, while the cumulative risk of POPs was still higher than 1, indicating continuous efforts are required to mitigate associated contamination.

Integrated remediation of sulfate reducing bacteria and nano zero valent iron on cadmium contaminated sediments.

Integrated-remediation technologies on heavy metal polluted sediments have received much attention. In this study, Cd contaminated sediments were treated with various conditions: sulfate reducing bacteria (SRB) only and SRB combined with different dosages of nano zero valent iron (nZVI (0.5-10 mg/g)). The immobilization of Cd was found in all remediation treatments according to the decreases of mobile Cd and the increases of more stable Cd compared with control. Five typical SRBs (Desulfobulbaceae, Desulfobacteraceae, Syntrophobacteraceae, Desulfovibrionaceae and Desulfomicrobiaceae) were identified having significant influences on Cd speciation transformation and they could stabilize Cd into sulfide precipitation through dissimilatory sulfate reduction (DSR). The ANOVA results of mobilization index and Cd concentration in overlying water both demonstrated that integrated-remediation systems with 5 mg/g and 10 mg/g of nZVI (Fe5 and Fe10 systems, respectively) presented better immobilization performance than conventional SRB only system (P < 0.05). It is confirmed that nZVI could stimulate the SRB bio-immobilization possibily through providing electrons and enhancing enzyme activities during DSR. The XPS analyses and Pourbaix diagrams revealed that mackinawite may be produced in the Fe10, resulting in the possible formation of Cd-S-Fe. This study indicates that integrated-remediation of SRB and nZVI have great potential in Cd immobilization of sediments, especially with higher addition of nZVI.

Biosafety of cadmium contaminated sediments after treated by indigenous sulfate reducing bacteria: Based on biotic experiments and DGT technique.

Sulfate reducing bacteria (SRB) biostabilization has attracted particular attention due to its ability to prevent and control heavy metal pollution. In this study, biotic experiments (immobilisation test of Daphnia (D.) magna, germination experiment of cucumber seeds, and in vitro experiment using gut juices of Sipunculus (S.) nudus) and diffusive gradients in thin films (DGT) technique were performed to investigate the biosafety of cadmium (Cd) contaminated sediments after being treated by indigenous SRB. Results showed that SRB treatment reduced Cd bioaccessibility of sediment to S. nudus, Cd levels in the overlying water and Cd bioavailability to D. magna. However, the treatment increased the biotoxicity of overlying water due to significant reduction in the root length and germination index of cucumber seeds. DGT results confirmed that SRB treatment increased Cd stability in sediment, and reduced its release from the sediment into the overlying water. The biotoxicity of overlying water was not caused by Cd, but possibly by the added culture medium, SRB itself, or its metabolites. More attention is required to assess the safety of SRB treatment when it is used to remediate environmental matrix contaminated by heavy metals.

The Bioaccumulation and Tissue Distribution of Arsenic Species in Tilapia.

Arsenic is a public concern due to its widespread occurrence and carcinogenicity. Consumption of arsenic-contaminated fish is an important exposure pathway for human health. This study focused on understanding how exposure to arsenic-contaminated fish is informative to human health risk assessment. While the bioaccumulation and tissue distributions of total arsenic concentration in fish are commonly reported, there are limited studies related to the time-course of arsenic species in various tissues. Using the Tilapia as a case, this study aimed to investigate the bioaccumulation and tissue distributions (liver, gastrointestinal (GI), muscle, and gill) of arsenic species in freshwater fish via diet-borne inorganic arsenic exposure. In particular, the Tilapia were exposed to arsenic (III) and As(V) for 32 days. The accumulation of arsenic in all tissues linearly increased with time in the first 10 days' exposure, while the arsenic levels remained stable in the following 20 days' exposure. The accumulation of arsenic in tissue followed the sequence of intestine > liver > gill > muscle. Meanwhile, more than 90% of arsenic was converted into organic form in liver, gill, and muscle, while organic arsenic contributed about 30⁻80% to the total arsenic in the GI. The percentage of organic form in muscle is the highest, followed by gill, liver, and intestine, and arsenobetaine is the main form of organic arsenic. While the exposure profiles of As(III) and As(V) are quite similar, the absorption rate of As(V) is relatively higher than that of As(III). Information provided here can be instrumental for exposure assessment and risk management for arsenic in aquatic environment.

Biostabilization of cadmium contaminated sediments using indigenous sulfate reducing bacteria: Efficiency and process.

Sulfate reducing bacteria (SRB) was used to stabilize cadmium (Cd) in sediments spiked with Cd. The study found that the Cd in sediments (≤600 mg kg-1) was successfully stabilized after 166 d SRB bio-treatment. This was verified by directly and indirectly examining Cd speciation in sediments, mobilization index, and Cd content in interstitial water. After 166 d bio-treatment, compared with control groups, Cd concentrations in interstitial water of Cd-spiked sediments were reduced by 77.6-96.4%. The bioavailable fractions of Cd (e.g., exchangeable and carbonate bound phases) were reduced, while more stable fractions of Cd (e.g., Fe-Mn oxide, organic bound, and residual phases) were increased. However, Cd mobilization in sediment was observed during the first part of bio-treatment (32 d), leading to an increase of Cd concentrations in the overlying water. Bacterial community composition (e.g., richness, diversity, and typical SRB) played an important role in Cd mobilization, dissolution, and stabilization. Bacterial community richness and diversity, including the typical SRB (e.g., Desulfobacteraceae and Desulfobulbaceae), were enhanced. However, bacterial communities were also influenced by Cd content and its speciations (especially the exchangeable and carbonate bound phases) in sediments, as well as total organic carbon in overlying water.

Interactions of natural organic matter on the surface of PVP-capped silver nanoparticle under different aqueous environment.

It is now widely accepted that coating on the nano-surface would critically dictate the uptake and cytotoxicity of engineering nanomaterials. However, the influence of natural organic matter (NOM) on the surface is quite limited to humic substances, while the diversity of NOM is neglected. In the present study, we tried to investigate the change of surface in the coexistence of bovine serum albumin (BSA) and humic acid (HA). The isothermal titration calorimetric measurements show that HA can combine with BSA in both freshwater or seawater, however, the patterns are different. In freshwater, HA lowered the adsorption of BSA on PVP-capped AgNPs through complexation with BSA, which prevented the contact of sulfur in BSA with PVP-AgNPs. Then in seawater, BSA retained its sulfur availability to bind with PVP-AgNPs. Furthermore, the toxicity of PVP-AgNPs incubated in the BSA/HA solution was evaluated by measuring the level of reactive oxygen species generated by Escherichia coli. The results indicated that, in seawater, the adsorbed BSA promoted the toxicity of PVP-AgNPs in the presence of Ca2+ and Mg2+, but the presence of HA limited this effect.

Bioremediation of cadmium- and zinc-contaminated soil using Rhodobacter sphaeroides.

Bioremediation using microorganisms is a promising technique to remediate soil contaminated with heavy metals. In this study, Rhodobacter sphaeroides was used to bioremediate soils contaminated with cadmium (Cd) and zinc (Zn). The study found that the treatment reduced the overall bioavailable fractions (e.g., exchangeable and carbonate bound phases) of Cd and Zn. More stable fractions (e.g., Fe-Mn oxide, organic bound, and residual phases (only for Zn)) increased after bioremediation. A wheat seedling experiment revealed that the phytoavailability of Cd was reduced after bioremediation using R. sphaeroides. After bioremediation, the exchangeable phases of Cd and Zn in soil were reduced by as much as 30.7% and 100.0%, respectively; the Cd levels in wheat leaf and root were reduced by as much as 62.3% and 47.2%, respectively. However, when the soils were contaminated with very high levels of Cd and Zn (Cd 54.97-65.33 mg kg-1; Zn 813.4-964.8 mg kg-1), bioremediation effects were not clear. The study also found that R. sphaeroides bioremediation in soil can enhance the Zn/Cd ratio in the harvested wheat leaf and root overall. This indicates potentially favorable application in agronomic practice and biofortification. Although remediation efficiency in highly contaminated soil was not significant, R. sphaeroides may be potentially and practically applied to the bioremediation of soils co-contaminated by Cd and Zn.

Trophic transfer of Cu, Zn, Cd, and Cr, and biomarker response for food webs in Taihu Lake, China.

Water, sediments, and aquatic organism samples were collected from Taihu Lake in China. Four types of typical heavy metal (Cu, Zn, Cd, and Cr) were analyzed to evaluate their concentrations and trophic transfer in food webs. The stable nitrogen isotope δ15N was used to investigate the trophic interactions. The concentrations of Cd and Zn in the sediments of Taihu Lake exceeded Level I of the China National Quality Standards for Soil. Zn accumulation was identified to increase with the trophic level. The bioconcentration of the four heavy metals in aquatic organisms was evident, with the invertebrates showing the highest bioconcentration factor in the food webs. Several biomarkers were investigated, including metallothionein (MT), malondialdehyde, and Na+/K+-adenosine triphosphatase activity. A positive correlation relationship was found between the MT content and heavy metal accumulation in organism tissues.

Removal of cadmium and zinc from contaminated wastewater using Rhodobacter sphaeroides.

Rhodobacter sphaeroides was used for bioremediation of wastewater polluted with cadmium (Cd) and zinc (Zn). The tolerance of the microorganism to selected heavy metals (HMs), as well as the effects of pH, temperature and inoculum size on the removal rate, was investigated. The remediation effects of R. sphaeroides were analysed at different initial concentrations of HMs. Bioremediation mechanisms were thoroughly discussed based on the results from the cell characterisation analysis. Cd and Zn could inhibit the growth of R. sphaeroides. However, Cd was more toxic than Zn, with corresponding EC50 values of 5.34 and 69.79 mg L-1. Temperature and pH had greater influence on the removal rate of HMs than inoculum size. The optimal conditions for temperature and pH were 35 °C-40 °C and pH 7, respectively. Initial concentration of HMs and remediation time also affected the removal rate. Rhodobacter sphaeroides had a relatively higher remediation effect under the present experimental conditions. The removal rates for Cd and Zn reached 97.92% and 97.76%, respectively. Results showed that biosorption and HM precipitation were the main bioremediation mechanisms. This information is necessary to better understand the removal mechanism of R. sphaeroides, and is significant for its pilot test and future practical application.

Validation of single nucleotide polymorphisms in invasive aspergillosis following hematopoietic cell transplantation.

Invasive aspergillosis (IA) is a significant cause of morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Previous studies have reported an association between IA development and single nucleotide polymorphisms (SNPs), but many SNPs have not been replicated in a separate cohort. The presence of a positive serum galactomannan assay (SGM+) has also been associated with a worse prognosis in patients with IA, and genetic determinants in this subset of patients have not been systematically studied. The study cohort included 2609 HCT recipients and their donor pairs: 483 with proven/probable IA (183 SGM+) and 2126 with no IA by standard criteria. Of 25 SNPs previously published, we analyzed 20 in 14 genes that passed quality control. Samples were genotyped via microarray, and SNPs that could not be genotyped were imputed. The primary aim was to replicate SNPs associated with proven/probable IA at 2 years; secondary goals were to explore the associations using an end point of SGM+ IA or proven/probable IA using a different genetic model or time to IA (3 months vs 2 years) compared with the original study. Two SNPs in 2 genes (PTX3, CLEC7a) were replicated. Thirteen SNPs in 9 genes had an association at P ≤ .05 using the secondary aims (PTX3, CLEC7a, CD209, CXCL10, TLR6, S100B, IFNG, PLG, TNFR1), with hazard ratios ranging from 1.2 to 3.29. Underlying genetic differences can influence development of IA following HCT. Identification of genetic predispositions to IA could have important implications in donor screening, risk stratification of recipients, monitoring, and prophylaxis.

The Daphnia magna role to predict the cadmium toxicity of sediment: Bioaccumlation and biomarker response.

To evaluate Daphnia magna role to predict the Cd toxicity in contaminated sediment, the Cd accumulation, metallothionein (MT), and mortality of D. magna exposed to overlying water system or water-sediment coexistence system were measured. The mortality, Cd accumulation, and MT in D. magna increased with the increasing Cd content in sediment. The Cd accumulation and MT in D. magna exposed to the coexistence system were significantly higher than those exposed to the overlying water system because of the ingestion of Cd-containing sediments by D. magna. However, the mortality did not significantly differ in the two systems, suggesting that mortality was less sensitive than accumulation and MT. The Cd accumulation/MT index can explain why the two systems had the similar mortality but different Cd accumulation and MT. Not all the percentage composition of nonresidual fractions (e.g., exchangeable, carbonate bound, and organic bound phases) significantly correlated with the difference values of Cd accumulation and MT, as well as Cd accumulation/MT. However, these indexes increased with the percentage composition of the nonresidual fractions, indicating that the distribution of Cd chemical fractions is crucial for its bioavailability and biotoxicity.

Replication of associations between genetic polymorphisms and chronic graft-versus-host disease.

Previous studies have identified single-nucleotide polymorphisms (SNPs) associated with the risk of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation. The current study determined whether these associations could be replicated in large cohorts of donors and recipients. Each SNP was tested with cohorts of patients having the same donor type (HLA-matched related, unrelated, or both) reported in the original publication, and testing was limited to the same genome (recipient or donor) and genetic model (dominant, recessive, or allelic) reported in the original study. The 21 SNPs reported in this study represent 19 genes, and the analysis encompassed 22 SNP association tests. The hazard ratio (HR) point estimates and risk ratio point estimates corresponding to odds ratios in previous studies consistently fall outside the 95% confidence intervals of HR estimates in the current study. Despite the large size of the cohorts available for the current study, the 95% confidence intervals for most HRs did not exclude 1.0. Three SNPs representing CTLA4, HPSE, and IL1R1 showed evidence of association with the risk of chronic GVHD in unrelated donor-recipient pairs from 1 cohort, but none of these associations was replicated when tested in unrelated donor-recipient pairs from an independent cohort. Two SNPs representing CCR6 and FGFR1OP showed possible associations with the risk of chronic GVHD in related donor-recipient pairs but not in unrelated donor-recipient pairs. These results remain to be tested for replication in other cohorts of related donor-recipient pairs.

The Potential Roles of Long Noncoding RNAs (lncRNA) in Glioblastoma Development.

Long noncoding RNA (lncRNA) may contribute to the initiation and progression of tumor. In this study, we first systematically compared lncRNA and mRNA expression between glioblastoma and paired normal brain tissues using microarray data. We found 27 lncRNA and 82 mRNA significantly upregulated in glioblastoma, as well as 198 lncRNA and 285 mRNA significantly downregulated in glioblastoma. We identified 138 coexpressed lncRNA-mRNA pairs from these differentially expressed lncRNA and genes. Subsequent pathway analysis of the lncRNA-paired genes indicated that EphrinB-EPHB, p75-mediated signaling, TNFα/NF-κB, and ErbB2/ErbB3 signaling pathways might be altered in glioblastoma. Specifically, lncRNA RAMP2-AS1 had significant decrease of expression in glioblastoma tissues and showed coexpressional relationship with NOTCH3, an important tumor promoter in many neoplastic diseases. Our follow up experiment indicated that (i) an overexpression of RAMP2-AS1 reduced glioblastoma cell proliferation in vitro and also reduced glioblastoma xenograft tumors in vivo; (ii) NOTCH3 and RAMP2-AS1 coexpression rescued the inhibitory action of RAMP2-AS1 in glioblastoma cells; and (iii) RNA pull-down assay revealed a direct interaction of RAMP2-AS1 with DHC10, which may consequently inhibit, as we hypothesize, the expression of NOTCH3 and its downstream signaling molecule HES1 in glioblastoma. Taken together, our data revealed that lncRNA expression profile in glioblastoma tissue was significantly altered; and RAMP2-AS1 might play a tumor suppressive role in glioblastoma through an indirect inhibition of NOTCH3 Our results provided some insights into understanding the key roles of lncRNA-mRNA coregulation in human glioblastoma and the mechanisms responsible for glioblastoma progression and pathogenesis. Mol Cancer Ther; 15(12); 2977-86. ©2016 AACR.

Effect of Nano-Al2O3 on the Toxicity and Oxidative Stress of Copper towards Scenedesmus obliquus.

Nano-Al2O3 has been widely used in various industries; unfortunately, it can be released into the aquatic environment. Although nano-Al2O3 is believed to be of low toxicity, it can interact with other pollutants in water, such as heavy metals. However, the interactions between nano-Al2O3 and heavy metals as well as the effect of nano-Al2O3 on the toxicity of the metals have been rarely investigated. The current study investigated copper toxicity in the presence of nano-Al2O3 towards Scenedesmus obliquus. Superoxide dismutase activity and concentration of glutathione and malondialdehyde in cells were determined in order to quantify oxidative stress in this study. Results showed that the presence of nano-Al2O3 reduced the toxicity of Cu towards S. obliquus. The existence of nano-Al2O3 decreased the growth inhibition of S. obliquus. The accumulation of copper and the level of oxidative stress in algae were reduced in the presence of nano-Al2O3. Furthermore, lower copper accumulation was the main factor that mitigated copper toxicity with the addition of nano-Al2O3. The decreased copper uptake could be attributed to the adsorption of copper onto nanoparticles and the subsequent decrease of available copper in water.

Genetic risk factors for sclerotic graft-versus-host disease.

Sclerotic graft-versus-host disease (GVHD) is a distinctive phenotype of chronic GVHD after allogeneic hematopoietic cell transplantation, characterized by fibrosis of skin or fascia. Sclerotic GVHD has clinical and histopathological similarities with systemic sclerosis, an autoimmune disease whose risk is influenced by genetic polymorphisms. We examined 13 candidate single-nucleotide polymorphisms (SNPs) that have a well-documented association with systemic sclerosis to determine whether these SNPs are also associated with the risk of sclerotic GVHD. The study cohort included 847 consecutive patients who were diagnosed with chronic GVHD. Genotyping was performed using microarrays, followed by imputation of unobserved SNPs. The donor rs10516487 (BANK1: B-cell scaffold protein with ankyrin repeats 1) TT genotype was associated with lower risk of sclerotic GVHD (hazard ratio [HR], 0.43; 95% confidence interval [CI], 0.21-0.87; P = .02). Donor and recipient rs2056626 (CD247: T-cell receptor ζ subunit) GG or GT genotypes were associated with higher risk of sclerotic GVHD (HR, 1.57; 95% CI, 1.13-2.18; P = .007 and HR, 1.66; 95% CI, 1.19-2.32; P = .003, respectively). Donor and recipient rs987870 (5'-flanking region of HLA-DPA1) CC genotypes were associated with higher risk of sclerotic GVHD (HR, 2.50; 95% CI, 1.22-5.11; P = .01 and HR, 2.13; 95% CI, 1.00-4.54; P = .05, respectively). In further analyses, the recipient DPA1*01:03∼DPB1*04:01 haplotype and certain amino acid substitutions in the recipient P1 peptide-binding pocket of the HLA-DP heterodimer were associated with risk of sclerotic GVHD. Genetic components associated with systemic sclerosis are also associated with sclerotic GVHD. HLA-DP-mediated antigen presentation, T-cell response, and B-cell activation have important roles in the pathogenic mechanisms of both diseases.

Bioremediation of lead contaminated soil with Rhodobacter sphaeroides.

Bioremediation with microorganisms is a promising technique for heavy metal contaminated soil. Rhodobacter sphaeroides was previously isolated from oil field injection water and used for bioremediation of lead (Pb) contaminated soil in the present study. Based on the investigation of the optimum culturing conditions and the tolerance to Pb, we employed the microorganism for the remediation of Pb contaminated soil simulated at different contamination levels. It was found that the optimum temperature, pH, and inoculum size for R. sphaeroides is 30-35 °C, 7, and 2 × 10(8) mL(-1), respectively. Rhodobacter sphaeroides did not remove the Pb from soil but did change its speciation. During the bioremediation process, more available fractions were transformed to less accessible and inert fractions; in particular, the exchangeable phase was dramatically decreased while the residual phase was substantially increased. A wheat seedling growing experiment showed that Pb phytoavailability was reduced in amended soils. Results inferred that the main mechanism by which R. sphaeroides treats Pb contaminated soil is the precipitation formation of inert compounds, including lead sulfate and lead sulfide. Although the Pb bioremediation efficiency on wheat was not very high (14.78% root and 24.01% in leaf), R. sphaeroides remains a promising alternative for Pb remediation in contaminated soil.

Clinical and Genetic Determinants of Cardiomyopathy Risk among Hematopoietic Cell Transplantation Survivors.

Cardiomyopathy has been recognized as a complication after hematopoietic cell transplantation (HCT). Using a nested case-cohort design, we examined the relationships between demographic, therapeutic, and selected cardiovascular disease risk factors among ≥1-year HCT survivors who developed cardiomyopathy before (n = 43) or after (n = 89) 1 year from HCT as compared to a randomly selected subcohort of survivors without cardiomyopathy (n = 444). Genomic data were available for 79 cases and 267 noncases. Clinical and genetic covariates were examined for association with the risk of early or late cardiomyopathy. Clinical risk factors associated with both early- and late-onset cardiomyopathy included anthracycline exposure ≥250 mg/m(2) and pre-existing hypertension. Among late-onset cardiomyopathy cases, the development of diabetes and ischemic heart disease further increased risk. We replicated several previously reported genetic associations among early-onset cardiomyopathy cases, including rs1786814 in CELF4, rs2232228 in HAS3, and rs17863783 in UGT1A6. None of these markers were associated with risk of late-onset cardiomyopathy. A combination of demographic, treatment, and clinical covariates predicted early-onset cardiomyopathy with reasonable accuracy (area under the curve [AUC], .76; 95% confidence interval [CI], .68 to .83), but prediction of late cardiomyopathy was poor (AUC, .59; 95% CI .53 to .67). The addition of genetic polymorphisms with marginal associations (odds ratios ≥1.3) did not enhance prediction for either early- or late-onset cardiomyopathy. Conventional cardiovascular risk factors influence the risk of both early- and late-onset cardiomyopathy in HCT survivors. Although certain genetic markers may influence the risk of early-onset disease, further work is required to validate previously reported findings and to determine how genetic information should be incorporated into clinically useful risk prediction models.

The homing and inhibiting effects of hNSCs-BMP4 on human glioma stem cells.

Malignant gliomas patients have a poor survival rate, partially due to the inability in delivering therapeutic agents to the tumors, especially to the metastasis of human glioma stem cells (hGSCs). To explore whether the human neural stem cells (hNSCs) with an over-expression of BMP4 (hNSCs-BMP4) can trace and inhibit hGSCs, in this study, we examined the migration of hNSCs to hGSCs using transwell assay in vitro and performed the fluorescent tracer experiment in vivo. We examined the proliferation, differentiation, apoptosis and migration of hGSCs after co-culturing with hNSCs-BMP4 in vitro and tested the tropism and antitumor effects of hNSCs-BMP4 in the established brain xenograft models of hGSCs. We found that hNSCs-BMP4 could secrete BMP4 and trace hGSCs both in vitro and in vivo. When compared to the normal human astrocytes (NHAs) and hNSCs, hNSCs-BMP4 could significantly inhibit the invasive growth of hGSCs, promote their differentiation and apoptosis by activating Smad1/5/8 signaling, and prolong the survival time of the tumor-bearing nude mice. Collectively, this study suggested that hNSCs-BMP4 may help in developing therapeutic approaches for the treatment of human malignant gliomas.