An efflux pump in genomic island GI-M202a mediates the transfer of polymyxin B resistance in Pandoraea pnomenusa M202.

BACKGROUND: Polymyxin B is considered a last-line therapeutic option against multidrug-resistant gram-negative bacteria, especially in COVID-19 coinfections or other serious infections. However, the risk of antimicrobial resistance and its spread to the environment should be brought to the forefront. METHODS: Pandoraea pnomenusa M202 was isolated under selection with 8 mg/L polymyxin B from hospital sewage and then was sequenced by the PacBio RS II and Illumina HiSeq 4000 platforms. Mating experiments were performed to evaluate the transfer of the major facilitator superfamily (MFS) transporter in genomic islands (GIs) to Escherichia coli 25DN. The recombinant E. coli strain Mrc-3 harboring MFS transporter encoding gene FKQ53_RS21695 was also constructed. The influence of efflux pump inhibitors (EPIs) on MICs was determined. The mechanism of polymyxin B excretion mediated by FKQ53_RS21695 was investigated by Discovery Studio 2.0 based on homology modeling. RESULTS: The MIC of polymyxin B for the multidrug-resistant bacterial strain P. pnomenusa M202, isolated from hospital sewage, was 96 mg/L. GI-M202a, harboring an MFS transporter-encoding gene and conjugative transfer protein-encoding genes of the type IV secretion system, was identified in P. pnomenusa M202. The mating experiment between M202 and E. coli 25DN reflected the transferability of polymyxin B resistance via GI-M202a. EPI and heterogeneous expression assays also suggested that the MFS transporter gene FKQ53_RS21695 in GI-M202a was responsible for polymyxin B resistance. Molecular docking revealed that the polymyxin B fatty acyl group inserts into the hydrophobic region of the transmembrane core with Pi-alkyl and unfavorable bump interactions, and then polymyxin B rotates around Tyr43 to externally display the peptide group during the efflux process, accompanied by an inward-to-outward conformational change in the MFS transporter. Additionally, verapamil and CCCP exhibited significant inhibition via competition for binding sites. CONCLUSIONS: These findings demonstrated that GI-M202a along with the MFS transporter FKQ53_RS21695 in P. pnomenusa M202 could mediate the transmission of polymyxin B resistance.

Investigation on risk factors of haemorrhagic fever with renal syndrome (HFRS) in Xuancheng City in Anhui Province, Mainland China.

Haemorrhagic fever with renal syndrome (HFRS), a rodent-borne disease, is a major public health concern in both developed and developing countries. China is the most severe endemic country in the world, constituting 90% of the cases. Although the incidence of HFRS has substantively decreased in most areas of China, HFRS has rebounded remarkably in some epidemic areas. Xuancheng is one of these areas. In this study, we collected the case data reported recently in Xuancheng and designed a 1:3 case-control study. The Chi-square test, univariate and multivariate logistic regression analysis were performed. In all cases, farmers made up the highest proportion of occupations. And there were 20 variables with statistical significance including indoor hygienic conditions; the surrounding environment; whether bitten by rats at work and other criteria. In addition, exposure to rodents and rats bites is a high-risk factor for HFRS. Rodent density was calculated at 20.9% (159/760), the virus carrier rate was 9.4% (15/159) and the index of rats with a virus was about 2.0%. Exposure to rodents and insect bites is also high-risk factors for HFRS among local residents in Xuancheng. More importantly, during the flood years, the increased density of rodents led to an increased risk of human exposure to rodents. As our statistical analysis proves, targeted strategies should be developed and implemented to reduce the incidence of local diseases in the future.

A novel cinnamide YLT26 induces breast cancer cells apoptosis via ROS-mitochondrial apoptotic pathway in vitro and inhibits lung metastasis in vivo.

BACKGROUND: Breast cancer is the leading cause of cancer death among women worldwide and metastasis is the major cause of treatment failure. Thus, new treatment options for breast cancer, especially, drugs which could prevent metastasis, are pressingly needed. METHODS: In the present study, we designed and synthesized a novel cinnamide derivative, (E)-N-(4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl)-3-(3,4,5-trimethoxyphenyl)acrylamide (YLT26), which displayed potent inhibitory effects on breast cancer cells. The cell viability, apoptosis-inducing effect and reactive oxygen species (ROS) production were examined in 4T1 cells following treatment with YLT26. Meanwhile, apoptosis-related proteins levels were determined by western blotting. Finally, we evaluated the effects of YLT26 on breast tumor growth, lung metastases in vivo and the infiltration of myeloid-derived suppressor cells (MDSCs) in lung tissue. RESULTS: Our results showed that the proliferation inhibitory effects of YLT26 were correlated with its apoptosis-inducing effect. Exposure to YLT26 induced mitochondrial transmembrane potential (∆Ψm) change, activated caspase-9, and downregulated the Bcl-2 expression, as well as enhanced ROS accumulation in 4T1 cells. Moreover, YLT26 significantly inhibited tumor growth without obvious side effects in the 4T1 tumor-bearing mice model. Immunohistochemistry analyze revealed YLT26 also induced apoptosis in vivo. More importantly, YLT26 also significantly inhibited lung metastases, which may be associated with the reduction of MDSCs. CONCLUSION: The present study suggested that YLT26 could inhibit breast cancer cells proliferation via ROS-mitochondrial apoptotic pathway, delay breast tumor progression, and suppress lung metastases by impacting on the immunologic microenvironment in vivo. © 2015 S. Karger AG, Basel.

Prognostic role of circulating tumor cells and disseminated tumor cells in patients with prostate cancer: a systematic review and meta-analysis.

Circulating tumor cells (CTCs) and disseminated tumor cells (DTCs) displayed their roles in prognosis prediction in prostate cancer. The objective of the present study was to conduct a systematic review and meta-analysis of published literature while investigating the correlation between survival outcome and CTCs or DTCs counts in patients with prostate cancer. Relevant literature was searched in Pubmed and Embase. Survival data of included study were extracted. Forrest plots were used to estimate the effect of CTCs/DTCs on the survival of patients. Publication bias was evaluated using Begg's test. The estimated HRs and 95 % confidence interval for the effect of CTCs/DTCs on overall survival (OS) and biochemical relapse-free survival (bRFS) or disease-free survival (DFS) were 2.43 [2.07, 2.86] (p<0.00001) and 2.15 [1.69, 2.73] (p<0.00001), respectively. Subgroup analysis revealed that CTCs were also relevant to poor prognosis (hazard ratio (HR) 2.43 [2.05, 2.89] for OS, HR 2.46 [2.08, 2.90] for bRFS/DFS). A similar result was yielded in DTCs (1.47 [1.21, 1.80] for DFS). CTCs/DTCs could also predict poor OS in metastatic prostate cancer (2.37 [1.99, 2.82], p<0.00001) and in localized stage (HR 1.84 [1.47, 2.28], p<0.00001). In addition, CTCs/DTCs detected by different methods, especially by CellSearch system (HR for OS 2.36 [1.95, 2.85] and HR for bRFS/DFS 2.53 [1.66, 3.85]), were relevant to poor prognosis. Available evidence supported the notion of the strong prognostic value of CTCs. CTCs are promising biomarkers that are clinically implemented in the therapeutic decision-making process in patients with prostate cancer.

The diagnostic role of a short screening tool--the distress thermometer: a meta-analysis.

PURPOSE: The Distress Thermometer (the DT) is a commonly used screening tool to detect distress in cancer patients. This meta-analysis aims to examine the diagnostic role and the optimal cut-off score of the DT compared with various different reference standards. METHODS: We searched PubMed and Embase from 1997 to September 2013 for relevant studies. After extracting data, we estimated the pooled sensitivity, specificity, likelihood ratios, diagnostic odds ratios, and constructed summary receiver operating characteristics curves to determine the optimal cut-off score. RESULTS: Forty-two relevant studies and 14,808 patients were included in total. When we pooled all the results together, the DT showed a good balance between pooled sensitivity (0.81, 95% confidence intervals (CI) 0.79-0.82) and pooled specificity (0.72, 95% CI 0.71-0.72) at the cut-off score of 4. The value of area under the curve (AUC) is 0.8321. When the DT is compared with the HADS-Total, the cut-off score of 4 maximized the balance between the pooled sensitivity (0.82, 95% CI 0.80-0.84) and pooled specificity (0.73, 95% CI 0.72-0.74). The AUC is 0.8432. CONCLUSIONS: This meta-analysis suggests that the DT is a valid tool to detect potential distress in cancer patients. According to our results, 4 as the optimal cut-off, is recommended. Further studies are needed to be done to examine the accuracy and optimal cut-off score in different regions globally and different cancer subtypes to guide the use of the DT for different patients.

Pyrrolidine-mediated direct preparation of (e)-monoarylidene derivatives of homo- and heterocyclic ketones with various aldehydes.

An efficient method for the facile synthesis of (E)-monoarylidene derivatives of homo- and heterocyclic ketones with various aldehydes in the presence of a pyrrolidine organocatalyst has been achieved. A range of α,ß-unsaturated ketones were obtained in moderate to high yields (up to 99%). Unlike the Claisen-Schmidt condensation process, the formation of undesired bisarylidene byproducts is not observed. The possible reaction mechanism suggests that the reaction proceeds via a Mannich-elimination sequence.

The integrative and conjugative element ICECiPOL15 mediates horizontal transfer of ß-lactam resistance gene in Chryseobacterium indoltheticum POL15.

OBJECTIVES: The dissemination of antibiotic resistance genes (ARGs) from the environment, including agricultural sources, is of increasing concern. In this study, we examined the antibiotic resistance profile and genomic sequence of a strain of Chryseobacterium indoltheticum obtained from an agricultural location. METHODS: The multidrug-resistant bacterial strain POL15 was isolated from the wastewater of a livestock farm in China. Whole-genome sequencing was performed followed by bioinformatics analyses to identify integrative and conjugative elements (ICEs) and ARGs. Mating assays were performed to analyse ICE transferability. RESULTS: Whole-genome sequencing and annotation showed that the genome of POL15 encodes ARGs. Additionally, an ICE named ICECiPOL15, which carries a class C ß-lactamase-encoding gene blaAQU, was identified in the POL15 genome. Genes encoding an integrase, an excisionase, a relaxase, a type IV coupling protein and conjugative transposon proteins involved in a type IV secretion system were also identified in ICECiPOL15. Sequence alignment revealed that ICECiPOL15 might have evolved from other Chryseobacterium species. The horizontal transferability of ICECiPOL15 was demonstrated by mating experiments between C. indoltheticum POL15 and Escherichia coli DL21. CONCLUSIONS: This study represents the first characterization of a mobilizable antibiotic resistance ICE in a species of C. indoltheticum and provides evidence that C. indoltheticum strains could be important reservoirs and vehicles for ARGs on livestock farms.

Clinical trial and performance evaluation of the Wantai HBsAg (CMIA) diagnostic kit for screening blood donors in China.

In China, according to the 'Technical Operating Procedures for Blood Stations (2019 Edition),' blood stations are authorized to utilize Chemiluminescence Immunoassay (CLIA) to detect pathogen markers linked with transfusion-transmissible infections. However, currently, there is no approved CLIA reagent for the screening of blood-borne diseases in China, specifically for the detection of Hepatitis B surface antigen. The objective of this research project is to conduct a comprehensive evaluation of the performance of the Wantai Chemiluminescent Microparticle Hepatitis B surface antigen reagent. This study evaluates the performance of the Wantai Chemiluminescent Microparticle Immunoassay (CMIA) on the Wan200 + analyzer in screening for Hepatitis B Surface Antigen (HBsAg) in blood samples. The clinical trial component of this evaluation is included as part of the documentation submitted to the National Medical Products Administration (NMPA) of China for the approval of blood screening reagents. The evaluation plan of this study encompasses two main components: clinical trials and performance assessment. We adopted a controlled trial design, utilizing the WanTai Chemiluminescent Microparticle Immunoassay (CMIA) on the Wan200 + analyzer and the Enzyme-Linked Immunosorbent Assay (ELISA) to screen for Hepatitis B Surface Antigen (HBsAg) in routine blood donor samples and reference serum panel samples. To ensure the accuracy of the screening, we additionally employed Abbott's ELISA reagents and HBV DNA for validation. The assessment primarily focused on key performance indicators such as sensitivity, specificity, and analytical sensitivity. Moreover, this clinical trial data has been included as part of the submission to China's National Medical Products Administration (NMPA). In the clinical trials of this study, a total of 10,470 blood donor samples underwent simultaneous testing using both CMIA and ELISA methods. Across two clinical trials, there was remarkable concordance between CMIA and the two ELISA reagents, with Kappa values exceeding 0.82. Among the 269 samples that were double-reactive in the enzyme immunoassay (ELISA) tests, CMIA exhibited a 100% reactivity detection rate. However, CMIA produced 14 and 6 false-positive results in the respective clinical trials, resulting in specificities of 99.73% and 99.89%. In contrast, the specificities for Wantai ELISA and Xin Chuang ELISA were both greater than 99.94%.When testing samples in the gray zone serum plates, CMIA's detection limit significantly exceeded that of the two ELISA assays. CMIA had a detection cutoff of 0.05 IU/mL, while the two ELISA reagents had cutoffs of 0.1 IU/mL and 0.09 IU/mL, respectively. CMIA's detection limits for the adr and adw subtypes were 0.05 IU/mL, and for the ay subtype, it was 0.1 U/mL. The detection limit for 10 HBV mutant samples was 0.5 U/mL. In 165 cases where ELISA tested negative but HBV DNA tested positive, CMIA detected 5 HBsAg-positive samples. This study evaluated the performance of the Wantai CMIA in screening for HBsAg among blood donors. The results demonstrate outstanding performance of CMIA in both clinical trials and performance assessments, detecting all true positive samples with a sensitivity of 100%. It exhibits excellent concordance with the two ELISA assays. Of particular note is its superiority in early detection of HBsAg in the screening of early-stage hepatitis B infections, reducing the window period compared to ELISA. CMIA achieves a specificity exceeding 99.73% for negative blood donors, aligning with the European Union's standards for blood screening assay specificity. In summary, Wantai's CMIA displays high sensitivity and specificity in blood donor screening, making it suitable for screening blood donors in China.

Evaluating the cost-effectiveness of low-level HBV DNA screening in occult hepatitis B infection donors: A study from Shandong Blood Center, China.

Objective: This study aimed to assess the efficacy of individual-donation nucleic acid testing (ID-NAT) in detecting occult hepatitis B virus infection (OBI) among anti-HBc positive blood donors, compared to minipool nucleic acid testing (MP-NAT). Methods: The present study analyzed data from the Shandong Blood Center in China during the period from January 2018 to June 2022, where HBsAg-negative blood donors were screened using the 6-sample minipool nucleic acid testing (6-sample MP NAT) method. NAT-positive samples underwent subsequent anti-HBc and anti-HBs testing. Approximately 5000 samples that passed the nucleic acid mixing test were randomly selected for anti-HBc testing, and over 100 anti-HBc positive samples underwent individual donor nucleic acid testing (ID-NAT). Any HBV DNA positive samples detected by ID-NAT were subsequently confirmed using alternative nucleic acid testing methods. Results: Among 220,445 HBsAg-negative blood donors, the positivity rate of HBV DNA detection using the 6-sample minipool nucleic acid testing (MP NAT) method was found to be 0.031% (69/220,445). Of the 67 HBV DNA positive samples, 55 (82.09%) and 25 (37.31%) were found to be positive for anti-HBc and anti-HBs, respectively, using the supplementary chemiluminescent microparticle immunoassay (CMIA). Among the 4797 HBsAg-negative/MP NAT-negative samples, 909 (18.95%) tested positive for anti-HBc. Further NAT testing was performed on 164 arbitrarily selected anti-HBc-positive/MP HBV DNA-negative samples, revealing a HBV DNA positivity rate of 1.22% (2/164). Conclusion: Using individual donation nucleic acid testing can significantly increase the detection rate of occult hepatitis B virus infection in anti-HBc-positive blood donors, resulting in a detection rate of 0.22% (1.22 × 0.1895). This rate is 8.10 times higher than the detection rate achieved by mixed testing methods (0.031%) [calculated as (0.22 + 0.031)/0.031]. Therefore, it is recommended to perform single HBV DNA testing on anti-HBc-positive blood donors, discard plasma with weakly positive or negative anti-HBs but positive anti-HBc, or avoid transfusing anti-HBc-positive plasma to recipients with weakly positive or negative anti-HBs to prevent HBV infection.

Glabridin inhibited the spread of polymyxin-resistant Enterobacterium carrying ICEMmoMP63.

Introduction: The role of integrative and conjugative elements (ICEs) in antibiotic resistance in Morganella morganii is unknown. This study aimed to determine whether an ICE identified in the M. morganii genome contributed to the polymyxin resistance. Methods: Whole-genome sequencing was performed followed by bioinformatics analyses to identify ICEs and antibiotic resistance genes. Conjugation assays were performed to analyze the transferability of a discovered ICE. A drug transporter encoded on the ICE was heterogeneously expressed in Escherichia coli, minimum inhibitory concentrations of antibiotics were determined, and a traditional Chinese medicine library was screened for potential efflux pump inhibitors. Results: An antibiotic resistance-conferring ICE, named ICEMmoMP63, was identified. ICEMmoMP63 was verified to be horizontally transferred among Enterobacteriaceae bacteria. G3577_03020 in ICEMmoMP63 was found to mediate multiple antibiotic resistances, especially polymyxin resistance. However, natural compound glabridin was demonstrated to inhibit polymyxin resistance. Discussion: Our findings support the need for monitoring dissemination of ICEMmoMP63 in Enterobacteriaceae bacteria. Combined glabridin and polymyxin may have therapeutic potential for treating infections from multi-drug resistant bacteria carrying ICEMmoMP63.

Peroxidase-like activity of Ru-N-C nanozymes in colorimetric assay of acetylcholinesterase activity.

Herein, the Ru-N-C nanozymes with abundant active Ru-Nx sites have been successfully prepared by pyrolyzing Ru(acac)3 trapped zeolitic-imidazolate-frameworks (Ru(acac)3@ZIF-8). Taking advantages of the remarkable peroxidase-mimicking activity, outstanding stability and reusability of Ru-N-C nanozymes, a novel biosensing system with explicit mechanism is strategically fabricated for sensitively determining acetylcholinesterase (AChE) and tacrine. The limit of detection for AChE activity can achieve as low as 0.0433 mU mL-1, and the IC50 value of tacrine for AChE is about 0.190 µmol L-1. The robust analytical performance in serums test verifies the great application potential of this assay in real matrix. Furthermore, "INH" and "IMPLICATION-AND" logic gates are rationally constructed based on the proposed colorimetric sensor. This work not only provides one sustainable and effective avenue to fabricate Ru-N-C-based peroxidase mimic with high catalytic performance, and also gives new impetuses for developing novel biosensors by applying Ru-N-C-based enzyme mimics as substitutes for the natural enzyme.

Prostate-Derived ETS Factor (PDEF) Modulates Yes Associated Protein 1 (YAP1) in Prostate Cancer Cells: A Potential Cross-Talk between PDEF and Hippo Signaling.

PDEF (prostate-derived ETS factor, also known as SAM-pointed domain containing ETS transcription factor (SPDEF)) is expressed in luminal epithelial cells of the prostate gland and associates with luminal phenotype. The Hippo pathway regulates cell growth/proliferation, cellular homeostasis, and organ development by modulating phosphorylation of its downstream effectors. In previous studies, we observed decreased levels of PDEF during prostate cancer progression. In the present study, we evaluated the effects of the expression of PDEF on total/phosphoprotein levels of YAP1 (a downstream effector of the Hippo pathway). We observed that the PC3 and DU145 cells transfected with PDEF (PDEF-PC3 and PDEF-DU145) showed an increased phospho-YAP1 (Ser127) and total YAP1 levels as compared to the respective PC3 vector control (VC-PC3) and DU145 vector control cells (VC-DU145). We also observed an increased cytoplasmic YAP1 levels in PDEF-PC3 cells as compared to VC-PC3 cells. Moreover, our gene set enrichment analysis (GSEA) of mRNA expression in PDEF-PC3 and VC-PC3 cells revealed that PDEF resulted in inhibition of YAP1 target genes, directly demonstrating that PDEF plays a critical role in modulating YAP1 activity, and by extension in the regulation of the Hippo pathway. We also observed a decrease in YAP1 mRNA levels in prostate cancer tissues as compared to normal prostate tissues. Our analysis of multiple publicly available clinical cohorts revealed a gradual decrease in YAP1 mRNA expression during prostate cancer progression and metastasis. This decrease was similar to the decrease in PDEF levels, which we had reported earlier, and we observed a direct correlation between PDEF and YAP1 expression in CRPC data set. To the best of our knowledge, these results provide the first demonstration of inhibiting YAP1 activity by PDEF in any system and suggest a cross-talk between PDEF and the Hippo signaling pathway.

Prostate-Derived Ets Factor (PDEF) Inhibits Metastasis by Inducing Epithelial/Luminal Phenotype in Prostate Cancer Cells.

Metastasis is the primary cause of prostate cancer morbidity and mortality. Our previous studies revealed that Sam pointed domain ETS transcription factor, a.k.a. prostate-derived ETS factor (SPDEF/PDEF), inhibits prostate cancer metastasis. However, the mechanism is still unclear. In this study, using microarray and gene set enrichment analysis, we discovered that PDEF upregulated epithelial/luminal differentiation-related genes while it suppressed stemness and epithelial-to-mesenchymal transition-related genes, especially Twist1. We also observed loss of PDEF and gain of Twist1 expression during prostate cancer progression in the TRAMP mouse model. Moreover, Twist1 knockdown resulted in upregulation of PDEF expression, suggesting a reciprocal regulation between PDEF and Twist1. Mechanistically, our ChIP-seq analysis revealed that PDEF directly regulated cytokeratin 18 (CK18) transcription through the GGAT motif within its putative promoter region. CK18 knockdown resulted in increased expression of Twist1, suggesting that PDEF regulated Twist1 in part via CK18. Our analysis of multiple clinical prostate cancer cohorts revealed an inverse relationship between PDEF expression and tumor grade, tumor metastasis, and poor patient survival. Furthermore, a two-gene signature of low PDEF and high Twist1 can better predict poor survival in prostate cancer patients than either gene alone. Collectively, our findings demonstrate PDEF inhibits prostate tumor progression, in part, by directly regulating transcription of CK18, and that PDEF/Twist1 expression could help distinguish between lethal and indolent prostate cancer.Implications: This study reports the novel findings that PDEF suppresses Twist1 partly via CK18 and that PDEF/Twist1 could help distinguish between lethal and indolent prostate cancer.Visual Overview: http://mcr.aacrjournals.org/content/molcanres/16/9/1430/F1.large.jpg Mol Cancer Res; 16(9); 1430-40. ©2018 AACR.

Androgen receptor (AR) cistrome in prostate differentiation and cancer progression.

Despite the progress in development of better AR-targeted therapies for prostate cancer (PCa), there is no curative therapy for castration-resistant prostate cancer (CRPC). Therapeutic resistance in PCa can be characterized in two broad categories of AR therapy resistance: the first and most prevalent one involves restoration of AR activity despite AR targeted therapy, and the second one involves tumor progression despite blockade of AR activity. As such AR remains the most attractive drug target for CRPC. Despite its oncogenic role, AR signaling also contributes to the maturation and differentiation of prostate luminal cells during development. Recent evidence suggests that AR cistrome is altered in advanced PCa. Alteration in AR may result from AR amplification, alternative splicing, mutations, post-translational modification of AR, and altered expression of AR co-factors. We reasoned that such alterations would result in the transcription of disparate AR target genes and as such may contribute to the emergence of castration-resistance. In the present study, we evaluated the expression of genes associated with canonical or non-canonical AR cistrome in relationship with PCa progression and prostate development by analyzing publicly available datasets. We discovered a transcription switch from canonical AR cistrome target genes to the non-canonical AR cistrome target genes during PCa progression. Using Gene Set Enrichment Analysis (GSEA), we discovered that canonical AR cistrome target genes are enriched in indolent PCa patients and the loss of canonical AR cistrome is associated with tumor metastasis and poor clinical outcome. Analysis of the datasets involving prostate development, revealed that canonical AR cistrome target genes are significantly enriched in prostate luminal cells and can distinguish luminal cells from basal cells, suggesting a pivotal role for canonical AR cistrome driven genes in prostate development. These data suggest that the expression of canonical AR cistrome related genes play an important role in maintaining the prostate luminal cell identity and might restrict the lineage plasticity observed in lethal PCa. Understanding the molecular mechanisms that dictate AR cistrome may lead to development of new therapeutic strategies aimed at restoring canonical AR cistrome, rewiring the oncogenic AR signaling and overcome resistance to AR targeted therapies.

Tuberculosis prevention in healthcare workers in China 10†years after the severe acute respiratory syndrome pandemic.

BSL3 and respiratory isolation wards protect healthcare workers from nosocomial TB infection in China http://ow.ly/PGvSl.

Down-regulation of MFG-E8 by RNA interference combined with doxorubicin triggers melanoma destruction.

The pathogenic mechanism of malignant melanoma involves the dynamic interplay of transformed cell and normal host cell, but cancer treatments always target each partition separately. In the tumor microenvironment, milk fat globule epidermal growth factor-8 (MFG-E8) is a secreted glycoprotein highly expressed in the vertical growth phase of melanoma, leading to tumor progression through coordinated αvß3 and αvß5 integrin signaling in tumor cells and host cells. Doxorubicin (Dox) is one of the most widely used antitumor drugs against a lot of solid tumors, including melanoma. In this work, Dox was used to combine with down-regulation of MFG-E8 by RNA interference (RNAi) in order to determine the synergistic effect of the antitumor activity in vivo. And the possible mechanisms were investigated. Results showed that combination group (MFG-E8 RNAi plus Dox) could inhibit the growth of melanoma more effectively than monotherapy or control groups. We found that the combination treatment induced more tumor cell apoptosis and inhibited more neovascularization than other groups. Moreover, this combination treatment attenuated CD4(+) CD25(+) Foxp3(+) Treg cells in tumor-infiltrating lymphocytes compared with other groups. Our findings suggested that MFG-E8 down-regulation enhanced the antitumor function of chemotherapy through coordinated cell apoptosis and immune-mediated mechanisms, which might be a feasible way for cancer therapy.

Synergic antitumor effect of SKLB1002 and local hyperthermia in 4T1 and CT26.

A de novo VEGFR2-inhibited compound SKLB1002 which is independently developed in our laboratory has been described for antiangiogenesis and displays a potent antitumor activity in vivo and in vitro. In the present investigation, we aim to prove that combination therapy of SKLB1002 with hyperthermia plays a synergy as an antitumor agent in solid tumor. In this study, we analyzed their synergetic inhibitory action on human umbilical vein endothelial cells (HUVEC), murine mammary cancer 4T1, murine colon carcinoma CT26 in vitro. Multiply-table tournament was performed to detect cell proliferation in vitro. 4T1 implantation and CT26 implantation in BALB/c mice were used to examine the activity of combination therapy of SKLB1002 with hyperthermia in vivo. Vascular density was determined by CD31 immunohistochemistry. TUNEL was used to measure apoptosis in tumor tissue. Metastasis assay was investigated via measurement of pulmonary metastasis nodules under the microscope. Potential toxicity of combination therapy was observed by histologic analysis of main organs stained with H&E. In vitro, the combination therapy significantly inhibited cell proliferation of HUVEC, 4T1 and CT26. In vivo, 4T1 and CT26 model experiments showed that combination therapy remarkably inhibited tumor growth and prolonged life span. When compared with controls, combination therapy reached 61 % inhibition index of tumor growth against CT26 and 51 % against 4T1. Moreover, it reduced angiogenesis and increased tumor apoptosis and necrosis. It was further found that combination therapy could efficiently prevent tumor from metastasizing to lung. Importantly, it had no toxicity to main organs including heart, liver, spleen, lung and kidney. Combination treatment has been proved to be a novel and strong strategy in clinical antitumor therapy. Our findings suggest that the combination therapy of SKLB1002 with hyperthermia has a synergistic antiangiogenesis, anticancer and promotion of apoptosis efficacy compared with controls. These findings could pave a new way in clinical tumor therapy.

Deconvoluting the role of reactive oxygen species and autophagy in human diseases.

Reactive oxygen species (ROS), chemically reactive molecules containing oxygen, can form as a natural byproduct of the normal metabolism of oxygen and also have their crucial roles in cell homeostasis. Of note, the major intracellular sources including mitochondria, endoplasmic reticulum (ER), peroxisomes and the NADPH oxidase (NOX) complex have been identified in cell membranes to produce ROS. Interestingly, autophagy, an evolutionarily conserved lysosomal degradation process in which a cell degrades long-lived proteins and damaged organelles, has recently been well-characterized to be regulated by different types of ROS. Accumulating evidence has demonstrated that ROS-modulated autophagy has numerous links to a number of pathological processes, including cancer, ageing, neurodegenerative diseases, type-II diabetes, cardiovascular diseases, muscular disorders, hepatic encephalopathy and immunity diseases. In this review, we focus on summarizing the molecular mechanisms of ROS-regulated autophagy and their relevance to diverse diseases, which would shed new light on more ROS modulators as potential therapeutic drugs for fighting human diseases.

Novel thermosensitive hydrogel for preventing formation of abdominal adhesions.

Adhesions can form after almost any type of abdominal surgery. Postoperative adhesions can be prevented by improved surgical techniques, such as reducing surgical trauma, preventing ischemia, and avoiding exposure of the peritoneal cavity to foreign materials. Although improved surgical techniques can potentially reduce formation of adhesions, they cannot be eliminated completely. Therefore, finding more effective methods to prevent postoperative adhesions is imperative. Recently, we found that a novel thermosensitive hydrogel, ie, poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCEC) had the potential to prevent postoperative adhesions. Using the ring-opening polymerization method we prepared a PCEC copolymer which could be dissolved and assembled at 55°C into PCEC micelles with mean size of 25 nm. At body temperature, a solution containing PCEC micelles could convert into a hydrogel. The PCEC copolymer was biodegradable and had low toxicity in vitro and in vivo. We found that most animals in a hydrogel-treated group (n = 10) did not develop adhesions. In contrast, 10 untreated animals developed adhesions that could only be separated by sharp dissection (P < 0.001). The hydrogel could adhere to peritoneal wounds and degraded gradually over 7-9 days, transforming into a viscous fuid that was completely absorbed within 12 days. The injured parietal and visceral peritoneum remesothelialized over about seven and nine days, respectively. This study confirms that PCEC hydrogel has potential application in the prevention of postoperative adhesions.

Celecoxib enhances the efficacy of 15-hydroxyprostaglandin dehydrogenase gene therapy in treating murine breast cancer.

PURPOSE: The overexpression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) has been proved to inhibit tumor growth and metastasis through degradation of prostaglandin E2 (PGE2), which is often overexpressed in various cancers and accelerates tumor progression. Cyclooxygenase-2 (COX-2), a synthase of PGE2, actively produces much PGE2 to counteract the 15-PGDH-induced antitumor efficacy. Here, we investigated the combinational effect by using pcDNA3.1(+) encoding mouse 15-PGDH gene therapy and celecoxib, a COX-2 inhibitor, in mouse breast cancers. METHODS: Mice bearing 4T1 were treated with short-term administration of the COX-2 inhibitor celecoxib (40 mg/kg/day) plus liposome-encapsulated mouse 15-PGDH in order to determine their synergistic antitumor activity in vivo. And the possible mechanisms were investigated. RESULTS: We observed that the combination treatment of 15-PGDH and celecoxib significantly inhibited tumor growth and lung metastases than monotherapy or controls. Moreover, the effect of combination treatment was associated with significant reduction of PGE2 in serum, which resulted from increased 15-PDGH and decreased COX-2 in tumor tissues. The tumor tissues in combination treatment presented more apoptotic cells and less microvessel density. Notably, the number of myeloid-derived suppressor cells in the spleen was also significantly decreased in the combination treatment than others. CONCLUSIONS: Our findings suggested that celecoxib increased the antitumor activity of 15-PGDH by synergistically blocking PGE2 pathway, which might be a new feasible way for cancer therapy.