Squaramide-catalyzed enantioselective Michael addition of nitromethane to 2-enoylazaarenes: synthesis of chiral azaarene-containing γ-nitroketones.

Bifunctional chiral squaramide-catalyzed highly enantioselective Michael addition of nitromethane to diverse 2-enoylazaarenes was successfully performed. This protocol provided a set of chiral azaarene-containing γ-nitroketones with up to 98% yield and 98% ee in a solvent-free catalytic system under mild conditions. Furthermore, gram-scale synthetic utility was also showcased.

The in Situ NHC-Palladium Catalyzed Selective Activation of B(3)-H or B(6)-H Bonds of o-Carboranes for Hydroboration of Alkynes: An Efficient Approach to Alkenyl-o-carboranes.

An in situ Pd-NHC catalyzed selective B(3,6)-H activation for hydroboration of internal alkynes has been accomplished under mild conditions. This work offers a facile approach for the synthesis of alkenyl-o-carboranes and has important reference for selective functionalization of B(3,6)-H bonds.

Palladium Catalyzed Selective B(3)-H Activation/Oxidative Dehydrogenative Coupling for the Synthesis of Bis(o-carborane)s.

A palladium catalyzed selective B(3)-H activation/oxidative dehydrogenative coupling for the synthesis of bis(o-carborane)s connected with B(3)-B(3') and B(3)-B(6') bonds has been developed for the first time. A plausible mechanism involving stepwise activation of B(3)-H and B(3'/6')-H bonds by PdII and PdIV was proposed. This work is the first example and the most efficient protocol for synthesis of bis(o-carborane)s connected with B(3)-B(3') and B(3)-B(6') bonds, which has important reference for design, synthesis, and application of bis(o-carborane)s in related fields.

Synthesis of Polyhedral Borane Cluster Fused Heterocycles via Transition Metal Catalyzed B-H Activation.

Aromatic heterocycles are ubiquitous building blocks in bioactive natural products, pharmaceutical and agrochemical industries. Accordingly, the carborane-fused heterocycles would be potential candidates in drug discovery, nanomaterials, metallacarboranes, as well as photoluminescent materials. In recent years, the transition metal catalyzed B-H activation has been proved to be an effective protocol for selective functionalization of B-H bond of o-carboranes, which has been further extended for the synthesis of polyhedral borane cluster-fused heterocycles via cascade B-H functionalization/annulation process. This article summarizes the recent progress in construction of polyhedral borane cluster-fused heterocycles via B-H activation.

Blocking Posttranslational Core Fucosylation Ameliorates Rat Peritoneal Mesothelial Cell Epithelial-Mesenchymal Transition.

BACKGROUND:: Core fucosylation (CF), catalyzed by α-1,6 fucosyltransferase (Fut8) in mammals, plays an important role in pathological processes through posttranslational modification of key signaling receptor proteins, including transforming growth factor (TGF)-ß receptors and platelet-derived growth factor (PDGF) receptors. However, its effect on peritoneal fibrosis is unknown. Here, we investigated its influence on epithelial-mesenchymal transition (EMT) of rat peritoneal mesothelial cells (PMCs) in vitro induced by a high-glucose (HG) culture solution. METHODS:: Rat PMCs were first cultured in a HG (2.5%) culture solution to observe the CF expression level (fluorescein isothiocyanate-lens culinaris agglutinin), we next established a knockdown model of rat PMCs in vitro with Fut8 small interfering RNA (siRNA) to observe whether inhibiting CF decreases the messenger RNA (mRNA) expression and protein expression of Fut8 and reverses EMT status. Rat PMCs were randomly divided into control group, mock group (transfected with scrambled siRNA), Fut8 siRNA group, HG group, HG + mock group, and HG + Fut8 siRNA group. Finally, we examined the activation of TGF-ß/Smad2/3 signaling and PDGF/extracellular signal-regulated kinase (ERK) signaling to observe the influence of CF on them. RESULTS:: CF, Fut8 mRNA, and protein expression were all significantly upregulated in HG- induced EMT model than those in the control rat PMCs (P < 0.05). Fut8 siRNA successfully blocked CF of TGF-ß receptors and PDGF receptors and attenuated the EMT status (E-cadherin and α-SMA and phenotypic changes) in HG-induced rat PMCs. In TGF-ß/Smad2/3 signaling, Fut8 siRNA did not suppress the protein expression of TGF-ß receptors and Smad2/3; however, it significantly suppressed the phosphorylation of Smad2/3 (relative expression folds of HG + Fut8 group vs. HG group: 7.6 ± 0.4 vs. 15.1 ± 0.6, respectively, P < 0.05). In PDGF/ERK signaling, Fut8 siRNA did not suppress the protein expression of PDGF receptors and ERK, but it significantly suppressed the phosphorylation of ERK (relative expression folds of HG + Fut8 group vs. HG group: 8.7 ± 0.9 vs. 15.6 ± 1.2, respectively, P < 0.05). Blocking CF inactivated the activities of TGF-ß and PDGF signaling pathways, and subsequently blocked EMT. CONCLUSIONS:: These results demonstrate that CF contributes to rat PMC EMT, and that blocking it attenuates EMT. CF regulation is a potential therapeutic target of peritoneal fibrosis.

Distribution Characteristics, Concentrations, and Sources of Cd and Pb in Laoxiawan Channel Sediments from Zhuzhou, China.

Twenty sediment cores encompassing surface (0-20 cm) and deeper (50-60 cm) sediment layers were retrieved from the 3000 m-long Laoxiawan Channel, which receives industrial effluents from Zhuzhou City (China). Analytical results showed that cadmium (Cd) concentrations ranged between 115.7-1126.7 and 108.8-2059.3 mg/kg while lead (Pb) values ranged between 234-3000 and 145-4292 mg/kg in the surface and bottom sediments, respectively. The results also indicated that high levels of Cd and Pb were present in the vicinity of the channel mouth and confluence area. Indices for potential ecological risk and geo-accumulation were used to evaluate the environmental effects and intensity of heavy metal pollution over time. High concentrations of Cd and Pb in the bottom sediments of Laoxiawan Channel were mainly associated with wastewater discharge (10(6) m(3)/year). Thus, the Laoxiawan Channel may be an important metal contaminant source for the Xiang River.

A novel mixed integer programming for multi-biomarker panel identification by distinguishing malignant from benign colorectal tumors.

Multi-biomarker panels can capture the nonlinear synergy among biomarkers and they are important to aid in the early diagnosis and ultimately battle complex diseases. However, identification of these multi-biomarker panels from case and control data is challenging. For example, the exhaustive search method is computationally infeasible when the data dimension is high. Here, we propose a novel method, MILP_k, to identify serum-based multi-biomarker panel to distinguish colorectal cancers (CRC) from benign colorectal tumors. Specifically, the multi-biomarker panel detection problem is modeled by a mixed integer programming to maximize the classification accuracy. Then we measured the serum profiling data for 101 CRC patients and 95 benign patients. The 61 biomarkers were analyzed individually and further their combinations by our method. We discovered 4 biomarkers as the optimal small multi-biomarker panel, including known CRC biomarkers CEA and IL-10 as well as novel biomarkers IMA and NSE. This multi-biomarker panel obtains leave-one-out cross-validation (LOOCV) accuracy to 0.7857 by nearest centroid classifier. An independent test of this panel by support vector machine (SVM) with threefold cross validation gets an AUC 0.8438. This greatly improves the predictive accuracy by 20% over the single best biomarker. Further extension of this 4-biomarker panel to a larger 13-biomarker panel improves the LOOCV to 0.8673 with independent AUC 0.8437. Comparison with the exhaustive search method shows that our method dramatically reduces the searching time by 1000-fold. Experiments on the early cancer stage samples reveal two panel of biomarkers and show promising accuracy. The proposed method allows us to select the subset of biomarkers with best accuracy to distinguish case and control samples given the number of selected biomarkers. Both receiver operating characteristic curve and precision-recall curve show our method's consistent performance gain in accuracy. Our method also shows its advantage in capturing synergy among selected biomarkers. The multi-biomarker panel far outperforms the simple combination of best single features. Close investigation of the multi-biomarker panel illustrates that our method possesses the ability to remove redundancy and reveals complementary biomarker combinations. In addition, our method is efficient and can select multi-biomarker panel with more than 5 biomarkers, for which the exhaustive methods fail. In conclusion, we propose a promising model to improve the clinical data interpretability and to serve as a useful tool for other complex disease studies. Our small multi-biomarker panel, CEA, IL-10, IMA, and NSE, may provide insights on the disease status of colorectal diseases. The implementation of our method in MATLAB is available via the website: http://doc.aporc.org/wiki/MILP_k.

[Changes of lymphocyte subsets before and after chemotherapy in colorectal carcinoma patients].

OBJECTIVE: To investigate the change of lymphocyte subsets before and after chemotherapy in colorectal carcinoma patients. METHODS: Twenty-one peripheral blood lymphocyte subsets from 62 colorectal carcinoma patients before and after FOLFOX4(including oxaliplatin, 5-fluorouracil and leucovorin) , FOLFRI(including irinotecan, 5-fluorouracil and leucovorin) , or XELOX(including oxaliplatin and capecitabine) regimen chemotherapy were examined by flow cytometry.The differences of these lymphocyte subsets were analyzed. RESULTS: After chemotherapy, the percentages of CD3(+), CD3(+)CD8(+), CD29(+), CD4(+)CD29(+), and CD4(+)CD25(+) cells in peripheral blood of colorectal carcinoma patients increased significantly, while the percentages of CD19(+) and human leukocyte antigen(locus) DR(HLA-DR) (+) cells decreased significantly(P<0.05) .The results of subgroup analysis showed that the patients' CD3(+)CD8(+) and CD4(+)CD25(+) cells increased significantly, CD19(+) and HLA-DR(+) cells decreased significantly after FOLFOX4 regimen chemotherapy(P<0.05) ;CD3(+)CD8(+) cells increased significantly and CD19(+) cells decreased significantly after XELOX regimen chemotherapy(P<0.05) ;while after FOLFRI regimen chemotherapy, there were no significant changes in all 21 lymphocyte subsets(P>0.05) . CD3(+), CD3(+)CD8(+), memory T lymphoctye(45RO(+)) , and CD4(+)CD45RO(+) cells increased significantly(P<0.05) in patients who received no more than 4 cycles of chemotherapy. However, in patients that received 5 to 8 cycles and more than 9 cycles chemotherapy, we only found significant decrease of HLADR(+) cells and significant increase of CD29(+) cells, respectively(P<0.05) . CONCLUSIONS: The humoral immunity is attenuated after chemotherapy in colorectal carcinoma patients. FOLFOX4 may suppress the cellular immunity.Chemotherapy that is less than 4 cycles will strengthens the cellular immunity by modulating body immunity arrangement;however, along with the increase of chemotherapy cycles, the cellular immunity gradually declines in these patients.

Serum peptidome variations in a healthy population: reference to identify cancer-specific peptides.

The emergence of mass spectrometry (MS)-based signatures as biomarkers has generated considerable enthusiasm among oncologists. However, variations in normal individuals also exist, and a better understanding of serum peptide patterns of healthy individuals will be important for further exploring disease-specific serum peptide patterns. Following development of a serum peptide pattern platform, we analyzed 500 serum samples obtained from healthy individuals. Samples from breast (n = 84), lung (n = 70), and rectal (n = 30) cancer patients were also examined. Extensive data analysis revealed negligible contributions of age to serum peptide patterns except in healthy individuals between 20-30 and 60+ years of age. Gender-related variations in the serum patterns of healthy individuals were only observed in 20-30 year-old individuals. Our results revealed substantial variation in individual peptide profiles, but 65 peptides were detected at a 20% higher frequency in the healthy population. A peptide profile was developed for each type of cancer, containing 10 discriminating peptides not prevalent in healthy individuals. Sequence identification of 111 signature peptides revealed that they fell into several tight clusters and most were exopeptidase products of serum resident proteins. We have obtained a MS-based serum peptide profile for healthy individuals, providing a reference for observing the occurrence of cancer-specific peptides.

Impact of chronic kidney disease on serum tumor markers concentrations.

BACKGROUND: Serum tumor markers have always been of clinical importance in the diagnosis, monitoring disease progression and therapy efficacy for patients with malignant diseases. However, elevated serum tumor markers are found in some benign conditions, especially in chronic kidney disease (CKD). The elevation of them in CKD might cause confusion and misuse of these tumor markers. We conducted this retrospective study to investigate which of the five widely used tumor markers including carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), cytokeratin 19 fragment antigen 21-1 (Cyfra21-1), squamous cell carcinoma antigen (SCC) and neuron specific enolase (NSE) are affected markedly by CKD, in order to use them more effectively. METHODS: Serum tumor marker concentrations, biochemical, hematological parameters, and urinalysis were measured in CKD patients and healthy controls. The positive rate and median tumor markers' level in CKD patients and controls, and those in CKD patients stratified by CKD grade were compared using nonparametric rank tests. Correlation analysis of serum tumor markers and other parameters in CKD patients were performed using the Spearman correlation coefficient. Multivariate Logistic regression analysis was used to estimate the important variables that caused elevated serum concentrations of these markers in CKD patients. RESULTS: The overall positive rates and serum concentrations of Cyfra21-1, SCC, CEA in CKD group were significantly higher than those in control group. Positive rate and serum concentrations of those tumor markers increased as kidney function decreased. Both univariate analysis and multivariate regression analysis showed that the elevations of those tumor markers were not only associated with kidney function, but also with nutritional status. CONCLUSIONS: Serum concentrations of Cyfra21-1, SCC, CEA are significantly influenced by kidney function, as well as nutritional status. Therefore, in clinical work, the indices of kidney function and nutritional status could be simultaneously measured to improve interpretation of the results of those tumor marker concentrations.

[Differential analysis of lymphocyte subsets between colorectal carcinoma patients and healthy individuals].

AIM: To investigate the differences of twenty lymphocyte subsets between colorectal carcinoma patients and healthy individuals. METHODS: Twenty peripheral blood lymphocyte subsets from 168 colorectal carcinoma patients and 102 healthy individuals were examined by flow cytometry (FCM). The differences of these lymphocyte subsets between healthy individuals and colorectal carcinoma patients at different clinical stages were analyzed statistically with SPSS 17.0 software. RESULTS: Compared with healthy people, the percentages of CD29(+), 45RA(+), CD4(+) CD45RO(+) and CD8(+) CD28(-) cells in peripheral blood of colorectal carcinoma patients increased significantly (P<0.05), while the percentages of NKT, 45RO(+), CD4(+) CD45RA(+), CD28(+) and CD8(+) CD28(+) cells decreased significantly (P<0.05). The percentage of CD8(+) CD28(-) cells in IV stage patients was significantly higher than that in healthy individuals, I+II and III stage patients (P<0.05). CONCLUSION: The cellular immunity of colorectal carcinoma patients is attenuated, while the humoral immunity is strengthened. The traditional lymphocyte analysis using CD3(+), CD4(+), NK or CD4(+)/CD8(+) ratio can not precisely evaluate the immunological function of colorectal carcinoma patients. The analysis of multi-lymphocyte subsets including CD8(+) CD28(+) and CD8(+) CD28(-) cells, is likely a better way to evaluate the immunological status of colorectal carcinoma patients.

Genes expression profiling of peripheral blood cells of patients with hepatocellular carcinoma.

HCC (hepatocellular carcinoma) is often diagnosed at an advanced stage with poor prognosis. Peripheral blood may be useful in cancer classification, and therefore we investigated the gene expression found by Affymetrix HG-U133 Plus2.0 microarray, with samples from nine HCC patients and five healthy NC (normal controls). A total of 726 probe sets showed significant differences based on the criteria of P<0.05 and absolute fold change >2. The genes were related to many biological functions, including immune response, transcription regulation and metabolism processes. Ten genes [IL-8 (interleukin 8), GOS2 (G0 /G1 switch gene 2), CXCR4 (CXC chemokine receptor 4), FOS, RPS24 (40S ribosomal protein S24), HAP90AA1, PFDN5, RPL27, GZMA and PFN1] showing significant differences were confirmed by real-time PCR in 54 HCC patients and 56 healthy NC. Seven genes [IL-8, GOS2, CXCR4, FOS, RPS24, HSP90AA1 (heat shock protein 90AA1) and PFN1] showed significant difference both in RT-PCR (reverse transcription-PCR) and microarray. Expression of IL-8 and FOS proteins was up-regulated in HCC compared with healthy controls. A gene signature in peripheral blood which can distinguish HCC patients and healthy controls may have been identified.

[Feasibility of peptide mass fingerprinting for differential diagnosis of IgA and non-IgA nephropathy].

OBJECTIVE: To investigate the feasibility of peptide mass fingerprinting for non-invasive differential diagnosis of IgA nephropathy (IgAN) from the non-IgA nephropathy (IgAN).? METHODS: According to the results of renal biopsy, 56 patients were divided into IgAN group (n=28) and non-IgAN group (n=28), and peptide mass fingerprints were acquired from these patients using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). RESULTS: Nine different peptides were identified between IgAN and non-IgAN. The two most distinctive differentially expressed peptides, with peptide peak values of 4476.46 and 1968.10, showed area under curve values of 86.18% and 79.77%. Principal component analysis demonstrated that the accumulated explained variance of the first 8 differential peptides reached 95%, suggesting the feasibility of differential diagnosis of IgAN from non-IgAN. Comparison with the Matrix protein database identified the peptide with a relative molecular mass of 5338.08 as a fragment of mucin 4 inform and the 2082.77 peptide as fragment of α1-II type collagen inform. CONCLUSION: MALDI-TOF MS is feasible for differential diagnosis of IgAN and non-IgAN and also has great potentials in the classification of the subtypes of other systemic diseases.

[Effects of Sisheng Decoction on spontaneous activity and serum concentration of malondialdehyde in mice with yin deficiency syndrome].

OBJECTIVE: To assess the therapeutic effects of Sisheng Decoction, a compound traditional Chinese herbal medicine, on a mouse model of yin deficiency syndrome induced by thyroid hormone, and to make the preliminary study on its mechanisms. METHODS: Simultaneous modeling and treatment were carried out. Sixty mice were randomly divided into six groups: normal group, yin deficiency model group, low-, medium- and high-dose Sisheng Decoction group and Shengmai oral liquid group. Normal group and yin deficiency model group were administered with double distilled water. Spontaneous activity and serum concentration of malondialdehyde in different groups were detected. RESULTS: The symptoms of yin deficiency syndrome such as xerostomia, dysphoria and fervescence were improved in the Sisheng Decoction groups. Compared with the yin deficiency model group, the spontaneous activity was increased and the serum concentration of malondialdehyde was decreased in the Sisheng Decoction groups (P<0.05). There was no significant difference between the Sisheng Decoction groups and the Shengmai oral liquid group (P<0.05). CONCLUSION: Medium- or high-dose Sisheng Decoction is effective for nourishing yin, clearing heat, engendering liquid and allaying thirst. The above effects of Sisheng Decoction may be realised by improving the spontaneous activity and resisting oxidative damage.

Hepatitis G virus genomic RNA is pathogenic to Macaca mulatta.

AIM: To explore the pathogenicity and infectivity of hepatitis G virus (HGV) by observing replication and expression of the virus, as well as the serological and histological changes of Macaca mulatta infected with HGV genomic RNA or HGV RNA-positive serum. METHODS: Full-length HGV cDNA clone (HGVqz) was constructed and proved to be infectious, from which HGV genomic RNA was transcribed in vitro. Macaca mulatta BY1 was intra-hepatically inoculated with HGV genomic RNA, HGV RNA-positive serum from BY1 was intravenously inoculated into Macaca mulatta BM1, and then BB1 was infected with serum from BM1. Serum and liver tissue were taken regularly, and checked with RT-PCR, in situ hybridization and other immunological, serological, histological assays. RESULTS: Serum HGV RNA was detectable in all the 3 Macaca mulattas, serological and histological examinations showed the experimental animals had slightly elevated alanine transaminase (ALT) and developed HGV viremia during the infectious period. The histology, immunohis-tochemistry, and in situ hybridization in liver tissues of the inoculated animals demonstrated a very mild hepatitis with HGV antigen expression in cytoplasm of hepatocytes. RT-PCR and quantitative PCR results showed that HGV could replicate in liver. CONCLUSION: The genomic RNA from full-length HGV cDNA is infectious to the Macaca mulatta and can cause mild hepatitis. HGV RNA-positive serum, from HGV RNA inoculated Macaca mulatta, is infectious to other Macaca mulattas. Macaca mulatta is susceptible to the inoculated HGV, and therefore can be used as an experimental animal model for the studies of HGV infection and pathogenesis.

[Identification of HCV antigen epitopes from a random 15-peptide library by anti-HCV polycloral antibody].

AIM: To analyze epitope recognized by anti-HCV antibodies; patients suffered from hepatitis C. METHODS: Anti-HCV Abs were purified from the patients serum through an affinity chromatography column which was prepared with sepharose 4B coupled with protein A. These Abs were used for biopanning of a phage-displayed random 15-peptide library. RESULTS: After 3 rounds of biopanning, the ratio of output to input increased to 3.3 x 10(3) and the false positive rate reduced to 0.2%, suggesting that the enrichment was effective. After the third round of biopanning, sixteen clones were selected to conduct binding test to Abs from the patients and normal person's sera. Nine of them were proved to react specifically to the sera from the patients. From the deduced insert sequence in the coat protein VIII, the core sequence of WPWS was found in 8 clones. The positive phage clones could react to different patients' and not react to normal person's sera. CONCLUSION: These findings indicate that WPWS motif in the short peptide may mimic the HCV epitope recognized by anti-HCV Abs.

[Recent Advance in Anti-CD20 Monoclonal Antibody Therapy in B-Cell Lymphoma]

Substantial advances in antigen-targeted lymphoma therapy have been achieved in recent years. Monoclonal antibodies targeting B-cell differential antigen CD20 have emerged as promising new treatments. CD20 is a 35 kD non-glycosylated transmembrane phosphoprotein. It is expressed on most mature B-lymphocytes and disappears from the surface of B lineage cells during terminal differentiation into plasma cells. The antigen appears to be involved in the regulation of B-cell development and differentiation and may mediate some of its effects by functioning as a calcium channel. Most importantly, CD20 is expressed on more than 95% of B-cell lymphomas and is not significantly internalized or shed. These features make it an ideal target for monoclonal antibody therapy for B-cell lymphomas. The results of clinical trials have showed that anti-CD20 monoclonal antibodies, which can be utilized in either unmodified form or as carrier for radioisotopes or cytotoxic agents, have significant effects and can be administrated safely with minimum side effects. Many studies have proposed several potential mechanisms to mediate the eradication of tumor cells targeted by anti-CD20 monoclonal antibodies. Ongoing prospective studies will establish some new therapeutic strategies with high anti-lymphoma specificity and low unspecific toxicity.