Design and synthesis of tetrazine bioorthogonal fluorogenic probes / 药学学报

Bioorthogonal fluorogenic probes are becoming an ideal tool for live-cell fluorescence imaging. With the tetrazine bioorthogonal fluorogenic probe that displays fluorescence enhancement, the tetrazine plays the dual-role of a bioorthogonal reaction unit and the fluorescence quenching unit. The "off" and "on" states of the fluorescence probe are mainly controlled through inverse electron demand Diels-Alder (IEDDA) bioorthogonal reaction. We designed a series of turn-on tetrazine fluorescent probes with Donor-π-Acceptor (D-π-A) structure to achieve a high signal-to-noise ratio and specificity of fluorescence imaging. This series of probes reacted with the dienophile bicyclononyne, and then generated pyridazine structure in-situ that acted as an electron acceptor, resulting in a new D-π-A effect of fluorescent dyes, turning on the intramolecular charge transfer (ICT) effect. By adjusting the electron-donating groups and the degree of conjugation, tunable fluorescence spectra between 400-647 nm with fluorescence turn-on enhanced up to 500-fold have been achieved. This research lays the foundation for the further optimization of tetrazine bioorthogonal fluorescent probes and their applications in molecular imaging and biomedical fields.

Clinical Effect and Safety of CCLG-ALL 2008 (high risk group) Protocol in the Treatment of Childhood Mixed Phenotype Acute Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical effect and safety of Chinese Children's Leukemia Group (CCLG)-ALL 2008 (high risk group) protocol in the treatment with childhood Mixed phenotype acute leukemia (MPAL).@*METHODS@#The clinical data of 15 new diagnosed patients with MPAL treated in our hospital from January 2013 to December 2017 were retrospectively analyzed, and received CCLG-ALL 2008 (high risk group) protocol chemotherapy.@*RESULTS@#One patient gave up treatment after diagnosed, and 14 children with MPAL after induction remission chemotherapy, 3 patients gave up, and 5 patients received consolidation chemotherapy, and 6 patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT). The complete remission (CR) rate was 85.7% at d33 of induction remission chemotherapy. The serious adverse event and treatment-related mortality (TRM) rate was 71.4% and 14.3%, respectively. The recurrence rate was 21.4% and the median time of relapse was 12(9.7-18.4) months. Except for 4 patients who gave up treatment, the 5-year event-free survival (EFS) rate in the other 11 patients was (54.5±15.0)%. The 5 years EFS of 4 patients who received consolidation chemotherapy was significantly lower than the 6 patients who received allo-HSCT after CR (25.0%±21.7% vs 83.3%±15.2%, P=0.033).@*CONCLUSION@#The CCLG-ALL2008 (for high-risk group) protocol in treatment of children with MPAL can get a high CR rate, but also with a high incidence of SAE. The patients received allo-HSCT after CR may have a good prognosis.

Tetrazine bioorthogonal click-to-release reaction for releasing peptides / 药学学报

This paper aimed to investigate the release efficiency of peptide at carbon terminal triggered by tetrazine bioorthogonal click-to-release reaction, and further explored the potential application of this reaction in functional modification and mild cleavage in solid-phase peptide synthesis. Thirteen peptide derivatives modified by trans-cyclooctene (TCO) were designed and synthesized, which were reacted with tetrazine to release the peptides. The results showed that the release rates of peptide were 90.0% to 97.7% in one hour. The strategy has good compatibility with the functional side-groups and the length of peptides, which expands the applications scope of tetrazine bioorthogonal click-to-release reaction. At the same time, a novel bifunctional trans-cyclooctene molecule was designed and synthesized. The active peptide GIRLRG was modified by fluorophore on the solid-phase resin, and released through tetrazine click-to-release reaction under mild condition, providing a new strategy for the solid-phase modification and release strategy of the peptide.

The study on the interactions between polycyclic aromatic hydrocarbon-albumin adducts and various risk factors to primary hepatocellular carcinoma / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the relationship between polycyclic aromatic hydrocarbon (PAH) exposure and hepatocellular carcinoma (HCC), and the interaction of PAH exposure and other HCC risk factors to HCC.</p><p><b>METHODS</b>Baseline blood samples, collected from 345 HCC cases and 961 controls, were used to determine the level of PAH-albumin adducts by competitive enzyme-linked immunosorbent assay. Conditional logistic regression analysis was used to assess the effect of PAH-albumin adducts on risk of HCC.</p><p><b>RESULTS</b>The mean level of PAH-albumin adducts was significantly higher in cases than in controls ((5.68 +/- 0.72) fmol/mg albumin vs (5.46 +/- 0.63) fmol/mg albumin) (u = 5.98, P < 0.01). When compared to subjects in the lowest quantile (< 1.76 fmol/mg albumin), there was an increase in risk of HCC, with adjusted ORs (95%CI) of 1.03 (0.65 - 1.60), 1.18 (0.76 - 1.78), 2.01 (1.42 - 2.82) for subjects in the second (1.76-fmol/mg albumin), the third (15.28-fmol/mg albumin), and the fourth quantile (> 34.21 fmol/mg albumin), respectively (chi(2)(trend) = 15.06, P < 0.01). There was a significant interaction between PAH-albumin adducts and HBsAg, family history of cancer and diabetes mellitus on HCC after adjusted for other risk factors, and relative excess risks due to the interaction (RERI) were 2.50 (u = 3.60, P < 0.01), 0.52 (u = 2.13, P < 0.05) and 0.88 (u = 2.26, P < 0.05), respectively.</p><p><b>CONCLUSION</b>PAH-albumin adducts was related with HCC, and there is a trend of HCC prevalence increasing with the content of PAH-albumin adducts. There are interactions between PAH-albumin adducts and HBV infection, family history of cancer and diabetes mellitus on HCC.</p>

Perturbed hepatic phosphoinositol 3-kinase signaling pathway in the rat with intrauterine growth restriction / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To determine the molecular mechanisms linking intrauterine growth restriction (IUGR) to adult type 2 diabetes mellitus, the effect of IUGR on the hepatic post-receptor insulin-signaling pathway was investigated in the adult offspring.</p><p><b>METHODS</b>The IUGR model was prepared by maternal protein-malnutrition. Western blotting analysis was undertaken to assess hepatic expression of insulin receptor substrate (IRS-2), phosphoinositol 3-kinase (PI-3K), protein kinase B (PKB), phosphorylated PKB-Ser473 and glycogen synthase kinase (GSK) 3 in 8-week-old male IUGR rats.</p><p><b>RESULTS</b>The basal levels of PI-3K protein decreased in IUGR rats compared with normal controls (p<0.01), whereas GSK-3beta protein level significantly increased in IUGR rats (p<0.01). Both PKB and phosphorylated PKB-Ser473 protein levels significantly decreased in the liver of IUGR rats compared with normal controls (p<0.01)). After insulin administration, phosphorylated PKB-Ser473 significantly increased to 182% of basal level in control rats(p<0.01); However, phosphorylation of PKB which responded to insulin was markedly blunted in IUGR rats compared with controls and only increased to 123% of basal level (p<0.05).</p><p><b>CONCLUSIONS</b>The level of PI-3K and PKB and phosphorylated PKB-Ser473 expression decreased in the liver of IUGR rats, whereas the levels of GSK-3beta protein increased. It may contribute to the pathogenesis of insulin resistance in the IUGR rats.</p>

Increased expression of gluconeogenic enzymes in the liver of IUGR rats and subsequent insulin resistance / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Intrauterine growth retardation (IUGR) is associated with insulin resistance in later life but the mechanism remains unclear. To explore the molecular mechanism of insulin resistance, we determined the expression of gluconeogenic enzymes as well as the expression of transcription factor which promotes gluconeogenesis in the liver of IUGR rats.</p><p><b>METHODS</b>Rat model of IUGR was established by maternal proteindouble ended arrowmalnutrition. Hepatic mRNA levels of the key enzymes for gluconeogenesis, PEPCK and G6Pase, and of peroxisome proliferator-activated receptor-gammacoactivator (PGC) -1alpha were measured by RT- PCR in male IUGR pup rats at 3 and 8 weeks of their lives. Hepatic PGC-1alpha protein levels were determined by Western blot.</p><p><b>RESULTS</b>The average birth weights of the IUGR group (4.97+/-0.83 g) were significantly lower than normal controls (6.54+/-0.52 g) (P<0.01). Until to 4 weeks of age, the weights of the IUGR rats increased to the control level and were higher than normal controls at 8 weeks of age (P<0.05). There were no significant differences in blood glucose and insulin concentrations between the IUGR rats and normal controls at 3 weeks of age. By 8 weeks of age, the IUGR rats showed high insulin concentrations (P<0.01) and high insulin resistance index (P<0.05) compared with the controls. Hepatic PGC-1alpha mRNA and protein levels as well as hepatic mRNA levels of PEPCK and G6Pase in IUGR rats significantly increased at 3 and 8 weeks compared with controls.</p><p><b>CONCLUSIONS</b>An increased PGC-1alpha expression may contribute to increased mRNA levels of PEPCK and G6Pase, and thus induce the development of insulin resistance in later life in IUGR rats.</p>

Changes and roles of VEGF and VCAM-1 in cerebrospinal fluid of children with viral encephalitis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Vascular endothelial cell injury contributes to the pathogenesis of viral encephalitis. This study was designed to investigate the roles of vascular endothelial growth factor (VEGF) and vascular cell adhesion molecule-1(VCAM-1) in cerebral spinal fluid (CSF) in the pathogenesis of viral encephalitis and in the evaluation of the severity and the prognosis of viral encephalitis in children.</p><p><b>METHODS</b>CSF VEGF and VCAM-1 levels were measured using ELISA in 65 children with viral encephalitis and 20 age-matched controls (10 cases of epilepsy and 10 cases of congenital abnormality).</p><p><b>RESULTS</b>CSF levels of VEGF and VCAM-1 in the viral encephalitis group in the acute phase were significantly elevated compared with those in the congenital abnormality (P<0.01) and the epilepsy groups (P<0.05). CSF levels of VEGF and VCAM-1 in the viral encephalitis group in the recovery phase decreased significantly and were similar to the levels of the epilepsy group, but remained higher than those in the congenital abnormality group (P<0.05). There was a positive correlation between CSF levels of VEGF and VCAM-1 in the viral encephalitis group in the acute and recovery phases. CSF levels of VEGF and VCAM-1 were positively correlated to CSF protein contents and the degree of MRI abnormality in the viral encephalitis group.</p><p><b>CONCLUSIONS</b>VEGF and VCAM-1 may participate in the pathogenesis of viral encephalitis. Detection of the two parameters may be helpful to the evaluation of the severity and prognosis of viral encephalitis.</p>

The methods to reduce the prevalence of lactose intolerance in children / 中华预防医学杂志

<p><b>OBJECTIVE</b>To identify methods in reducing the prevalence of lactose intolerance in children.</p><p><b>METHODS</b>A hydrogen respiration test (HRT) method was used in screening lactose intolerance (LI) subjects after taking 25 g of lactose among 106 children aged from 10 to 11 years old in a primary school located in the suburban area of Beijing. A cross-design was used to detect the effects of low lactose milk, yogurt and cereal-effect among 68 selected LI children.</p><p><b>RESULTS</b>The incidence of LI was 80.2% after the children took 25 g of lactose, and after taking a 250 ml of full milk, lactase-fermented milk, coinfected milk, yogurt, or milk with meal, the LI incidences were 21.1% (12/57), 0% (0/25), 6.1% (2/33), 8.6% (3/35) and 13.6% (3/22) respectively.</p><p><b>CONCLUSION</b>Low lactose milks and yogurt could reduce the LI incidence among LI children significantly.</p>

The relationship between p120ctn translocation and malignant features of hepatocellular carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of catenin p120 (p120ctn) translocation on the malignant features of hepatocellular carcinoma and its interrelation with beta-catenin in E-cadherin-mediated cell signaling.</p><p><b>METHODS</b>Expression and translocation of p120ctn, tyrosine phosphorylation, and its binding capacity to E-cadherin were detected by DNA transfection, immunoblotting and immunoprecipitation. Cellular localization of p120ctn and beta-catenin was detected by immunofluorescent microscopy. Cell adhesion, cell migration and cell proliferation were also studied.</p><p><b>RESULTS</b>Expression of p120ctn increased after cells transfected with p120ctn isoform 3A, and it was located mainly at cell-cell contact region. Its binding to E-cadherin was enhanced. After EGF stimulation, tyrosine phosphorylation of p120ctn was increased, membrane expression of p120ctn and beta-catenin was decreased while cytosol expression was increased. It was translocated into the nucleus, cell adhesiveness was increased but mobility decreased. With over-expression of p120ctn, beta-catenin was recruited by nucleus export. Cell proliferation was reduced but it was increased after EGF treatment.</p><p><b>CONCLUSION</b>p120tn plays an important role in cell adhesion, migration and proliferation of hepatocellular carcinoma, and its tyrosine phosphorylation might contribute to this mechanism. There might be a competitive relationship between p120ctn and beta-catenin.</p>