A Co-Encapsulation of Coenzyme Q10 and Curcumin in Liposomes Coated with Chitosan (Q10-Cur-Lip-Chi) with Enhanced Solubility and Stability for Good Release Performance and Antioxidative Activity.

BACKGROUND: Coenzyme Q10 (Q10) is a powerful lipophilic antioxidant with poor solubility in aqueous media. Curcumin (Cur) is a natural polyphenolic phytochemical molecule with poor aqueous solubility. The liposome is an improved administration of drugs because it is biocompatible and permeable for nutraceutical delivery. Chitosan, a hydrophilic polymer, is often used as a polymer coating for its good biocompatible and biodegradable properties, and its relatively low toxicity level. METHODS: Q10 and Cur co-loaded liposomes coated with chitosan (Q10-Cur-Lip-Chi) were constructed. The co-encapsulation of Q10 and Cur in liposomes coated with chitosan was verified by TEM, DLS, DSC, FT-IR, and XRPD. The release profile and antioxidant activity of Q10-Cur-Lip-Chi were accessed. RESULTS: The particle size of Q10-Cur-Lip-Chi was about 1440 nm with narrow particle distribution. A satisfactory encapsulation efficiency (EE) of Q10 was about 98%, and 25% for that of Cur. Q10-Cur- Lip-Chi showed higher solubility and better pH resistance with 98.5% of Q10 and Cur retention at pH 7.0 - 9.0. Q10-Cur-Lip also showed great salt stability with a vesicle size change of less than 5%. PSof Q10-Cur-Lip-Chi changed less than 10% at 4°C of storage. Q10-Cur-Lip-Chi also exhibited a good controlled release profile with its accumulative release of less than 34% for Q10 and 30% for curcumin after 24 h. The Q10-Cur-Lip-Chi performed a synergistic effect on antioxidant activity reaching 41.86±1.84%, which was 5.9 times higher than that of Q10, 2.5 times higher than that of Cur, and 1.7 times higher than that of the mixture. CONCLUSION: The co-encapsulation Q10-Cur-Lip-Chi improves the solubility and stability of Q10 and Cur for good release performance and antioxidative activity.

Machine learning applications for prediction of relapse in childhood acute lymphoblastic leukemia.

The prediction of relapse in childhood acute lymphoblastic leukemia (ALL) is a critical factor for successful treatment and follow-up planning. Our goal was to construct an ALL relapse prediction model based on machine learning algorithms. Monte Carlo cross-validation nested by 10-fold cross-validation was used to rank clinical variables on the randomly split training sets of 336 newly diagnosed ALL children, and a forward feature selection algorithm was employed to find the shortest list of most discriminatory variables. To enable an unbiased estimation of the prediction model to new patients, besides the split test sets of 150 patients, we introduced another independent data set of 84 patients to evaluate the model. The Random Forest model with 14 features achieved a cross-validation accuracy of 0.827 ± 0.031 on one set and an accuracy of 0.798 on the other, with the area under the curve of 0.902 ± 0.027 and 0.904, respectively. The model performed well across different risk-level groups, with the best accuracy of 0.829 in the standard-risk group. To our knowledge, this is the first study to use machine learning models to predict childhood ALL relapse based on medical data from Electronic Medical Record, which will further facilitate stratification treatments.

Expansion and activation of granulocytic, myeloid-derived suppressor cells in childhood precursor B cell acute lymphoblastic leukemia.

Precursor B cell acute lymphoblastic leukemia (B-ALL) is a B cell-derived, malignant disorder with the highest incidence among children. In addition to the genetic abnormality, a dysregulated immune system also has an important role in the pathogenesis of B-ALL. Myeloid-derived suppressor cells (MDSCs) represent one of the key drivers in immune tolerance against tumor cells, including various solid tumors and hematologic malignancies. The role of MDSCs in B-ALL remains poorly understood. Here, we showed that the granulocytic (G)-MDSC population was significantly elevated in both the peripheral blood and BM of patients with B-ALL, when compared with age-matched healthy controls. G-MDSCs levels correlated positively with clinical therapeutic responses and B-ALL disease prognostic markers, including minimal residual disease, and the frequencies of CD20+ and blast cells. The immunosuppressive function of B-ALL-derived G-MDSCs was mediated through the production of reactive oxygen species and required direct cell-cell contact, with the potential participation of STAT3 signaling. Overall, the results of our study support accumulation and activation of G-MDSCs as a novel mechanism of immune evasion of tumor cells in patients with B-ALL and may be a new therapeutic target.

Vitamin D deficiency and the risk of anemia: a meta-analysis of observational studies.

AIMS: Anemia and vitamin D deficiency (VDD) are both very important health issues, recent accumulating evidence shows that VDD is prevalent in individuals with anemia. This meta-analysis aimed to detect a relationship between VDD and anemia. METHODS: We identified eligible studies by searching the Pub Med, Embase and Cochrane Library before October 2014. Quality assessments were performed with the Newcastle-Ottawa Scale. Heterogeneity was evaluated by Cochran's Q test and source of heterogeneity was detected by subgroup analysis and sensitivity analysis. RESULTS: A total of seven studies involving 5183 participants were included in the meta-analysis. VDD was associated with an increased incidence of anemia (OR = 2.25, 95% CI = 1.47-3.44), with significant evidence of heterogeneity among these studies (p for heterogeneity < 0.001, I(2) = 84.0%). The subgroup and sensitivity analysis confirmed the stability of the results and no publication bias was detected. CONCLUSION: Our outcomes showed that VDD increased the risk of developing anemia. More researches are warranted to clarify an understanding of the association between VDD and risk of anemia.

[Prediction and analysis of epitopes of hemagglutinin of measles virus].

OBJECTIVE: To discuss the antigenic change caused by the mutation of amino acid on the epitopes of the hemagglutinin of measles virus. METHODS: The B cell linear epitopes in the hemagglutinin were predicted with bioinformatics software. Peptide pairs, which located on the same region but originated from measles vaccine and wild-type virus respectively, were designed and synthesized. After detecting the immunogenicity of peptides with indirect ELISA assay, sera against each peptide was prepared. Antigenic specificity between the two peptides within each peptide pair were tested by using cross ELISA assay, and then antigen ratios were calculated. RESULTS: All the synthesized peptides could bind with immune sera against measles virus, of which the peptide pair CW23/CW22 designed on the epitope region (273-282 aa) possessed the highest binding ability, while the peptide pair CW150/CW151 designed on the non-epitope region (418-427 aa) showed the lowest binding ability. The difference in antigenic specificity between the two peptides from different sources was significant. The antigenic ratio was up to 16 between CW23 (vaccine-originated) and CW22 (wild-type originated) , and 2.877±0.583 between CW123 (vaccine-originated) and CW124 (wild-type originated) (236-246 aa) . On the non-epitope regions, the antigenic ratios was only 1.631±0.481 between peptide pair CW125 and CW126 (356-364 aa) , but reached to 10.367±1.617 between CW150 and CW151. CONCLUSION: Although there were several conservative epitopes, specific amino acid mutation on the predicted epitope or non-epitope regions might cause the antigenic change of wild-type measles virus.

[Variations on hemagglutinin gene of Zhejiang measles virus strains and differences with measles strains circulated both at home and abroad].

OBJECTIVE: To investigate the variations on hemagglutinin (H) gene of measles virus (MV) in Zhejiang province, and to analyze the differences with strains circulated both at home and abroad. METHODS: In total, 33 MV strains isolated in Zhejiang province between 1999 and 2011 were collected.RNA of the isolated MV strains was extracted and the complete sequences on H gene were amplified using RT-PCR assay. The products were compared with the Chinese vaccine strain Shanghai-191, which was downloaded from GenBank, and other 95 different MV strains from all over the world. RESULTS: 33 MV strains, isolated from the throat swab specimens collected from MV patients in Zhejiang province during 1999 to 2001, were used to conduct phylogenetic analysis with MV strains circulated in other areas of China during 1993 to 2007. The phylogenetic tree based on H gene sequences showed that all the Zhejiang MV strains located in H1a cluster, and no apparent time series and geographic restrictions were observed. Compared to the referenced vaccine strain Shanghai-191, the average variation rate on nucleotides and amino acids, and the evolutionary rate of H1a viruses from China during 2003 to 2011 were separately 5.15%, 4.44% and 5.81%, which were higher than the rates of H1a viruses during 1965 to 1993 (4.75%, 3.86% and 5.30%), and the rates of viruses during 1994 to 2002 (4.80%, 4.08% and 5.37%).However, the dn/ds ratios of strains within the three time periods were 0.19,0.21 and 0.23 respectively, which indicated that no evidence of positive selection was found on H1a MV strains during 1993 to 2011. A 24 stable amino acid variation sites on H gene was found between H1a viruses during 2003 to 2011 and the vaccine strain Shanghai-191. The largest variation occurred between vaccine and H1a strains, with 0.053 of the p-distance and 26-28 of amino acid mutations.However, only 15 stable amino acid variations were found between vaccine strain and genotype B3 or D4 strains.In addition, significant differences were found between H1a viruses and genotype B or D viruses, with 0.074 and 0.071 of p-distance and 27-33 of amino acid differences. CONCLUSION: Significant differences were found on H gene between MV strains subtype H1a and vaccine strains and other genotype strains. The variations were enlarged with the time coursing; therefore, the surveillance on variation of Chinese MV strains should be taken into account.

[Comparative analysis on the complete genome sequence of mumps epidemic strain and mumps vaccine strain S79 isolated in Zhejiang province, China between year 2005 and 2010].

OBJECTIVE: To compare the differences in the complete genome sequence between mumps epidemic strain and mumps vaccine strain S79 isolated in Zhejiang province. METHODS: A total of 4 mumps epidemic strains, which were separated from Zhejiang province during 2005 to 2010, named as ZJ05-1, ZJ06-3, ZJ08-1 and ZJ10-1 were selected in the study. The complete genome sequences were amplified using RT-PCR. The genetic differences between vaccine strain S79 and other genotype strains were compared; while the genetic-distance was calculated and the evolution was analyzed. RESULTS: The biggest difference between the 4 epidemic strains and the vaccine strain S79 was found on the membrane associated protein gene; whose average nucleotide differential number was 42.5 +/- 3.0 and the average variant ratio was 13.6%; while the mean amino acid differential number was 12.8 +/- 1.5 and the average variant ratio was 22.4%. The smallest difference among the 4 epidemic strains and the vaccine strain was found in stromatin genes, whose average nucleotide differential number was 73.8 +/- 2.5 and the average variant ratio was 5.9%; while the mean amino acid differential number was 3.0 +/- 0.8 and the average variant ratio was 0.8%. The dn/ds value of the stromatin genes of the 4 epidemic strains reached the highest, as 0.6526; but without any positive pressure (dn/ds < 1, chi2 = 0.87, P > 0.05). There were mutations happened on the known antigen epitope, as 8th amino acid of membrane associated protein genes and on the 336th and 356th amino acid of hemagglutinin/neuraminidase proteins. Compared with the vaccine strain, the glycosylation sites of ZJ05-1, ZJ06-3, ZJ08-1 and ZJ10-1 increased 1, 1, 2 and 2 respectively. The complete amino acid sequence of all strains showed that there were 17 characteristic sites found on the genotype-F mumps strain. Within the complete genome, the genetic-distance between epidemic strains and vaccine strains in Zhejiang province (0.071) was significantly larger than the genetic-distance between strains in Yunnan province (0.013); the difference showing statistical significance (t = 4.14, P < 0.05). Except nucleocapsid protein genes, all the genes shared similar evolution tree. CONCLUSION: There were significant differences found in the genes between mumps epidemic strain and mumps vaccine in Zhejiang province.

[Study on the genome sequence of measles viruses circulated in Zhejiang province during 1999 to 2011].

OBJECTIVE: To study the genetic variations between measles vaccine strain S191 and strains that circulated in Zhejiang province causing the epidemics during 1999 to 2011. METHODS: Complete sequence of the nine Zhejiang measles strains were amplified by RT-PCR assay. Products were sequenced and the obtained sequences were aligned and analyzed with vaccine strains S191 and the major epidemic strains isolated in foreign countries. RESULTS: The homology of amino acid among the nine Zhejiang strains were 98.77% - 99.89%. The strains were not affected by positive selection and the variations on each gene were still in random drift. Compared to vaccine strain S191, there were 135 to 159 amino acid changes in Zhejiang measles virus, in which 113 points were common variable positions, resulting in mutations on five glycosylation sites. At the nucleotide level, the biggest differences between the Zhejiang strains and the vaccine strain S191 were found on N gene, with the average divergent ratio as 5.5%, while the biggest one was P protein, in the amino acid level, with the average mutation rate as 7.7%. In addition, with the complete genome sequences, the genetic distance between Zhejiang epidemic strains and vaccine strains was greater than the distances between epidemic strains of genotype D(4), B(3) and vaccine strains (t = -9.76, P < 0.05; t = -12.39, P < 0.05). CONCLUSION: There were significant differences found in the each of the genes between Zhejiang epidemic strains and the vaccine strain S191. The differences between the current vaccine strains and H genotype epidemic strains were much larger than the differences between the vaccine and the foreign epidemic strains (genotype D(4), B(3)). Therefore, we should pay close attention to this trend, and to develop candidates for the development of vaccines, as early as possible.

[Molecular epidemiological study on rubella virus strains isolated in Zhejiang province, China, 2005-2010].

OBJECTIVE: To analyze the molecular epidemiological characteristic of rubella virus strains isolated in Zhejiang province from 2005 to 2010, to provide basic data for rubella prevention and control. METHODS: Rubella virus strains were isolated on Vero cells from the suspected patients' specimens collected in Zhejiang province during 2005 to 2010. Partial fragments of the structural gene of Zhejiang rubella strains were amplified, using nested reverse transcription-polymerase chain reaction (RT-PCR). The amplified products were sequences and analyzed. RESULTS: In total, 7 rubella strains were isolated from 52 clinical specimens, of which six were classified as genotype 1E and only one was characterized as genotype 2B. In the phylogenetic tree, the Zhejiang 1E genotype rubella strains were located in the same branches with Hongkong or Hainan isolates respectively, but the Zhejiang 2B genotype strain were located in the same branch with oversea strain BuenosAires. ARG/46.08. Through p-distance analysis, results also showed that the Zhejiang 2B genotype strain was closer to the 2B strains isolated from overseas (0.011) than those strains from other provinces of China (0.023). Compared with Chinese vaccine strain BRD II, the homology on three structural genes was C > E2 > E1, but the homology of deduced amino acid sequence was E1 > C > E2, with corresponding 3, 11 and 23 amino acid mutations. There was only one amino acid on E1 gene with entropy value higher than 0.600, but seven sites on E2 gene with entropy value appeared higher than 0.600 and one with entropy value higher than 1.000. CONCLUSION: Two genotypes of rubella virus had circulated in Zhejiang province during 2005 to 2010. Genotype 1E appeared to be the predominant genotype and 2B being an imported one. Amino acid sequence of E1 gene from Zhejiang rubella strains was comparatively conserved, but E2 gene was hypervariable. Study on rubella virus E2 and C gene should be conducted in the epidemiological surveillance program of rubella.

[Genetic variation of phosphoprotein (P) gene from measles epidemic strains in Zhejiang province].

OBJECTIVE: To investigate the genetic characteristics and variation within the phosphoprotein (P) gene of measles epidemic strains circulated in Zhejiang province. METHODS: The whole sequence of P gene of the epidemic strains related to Zhejiang Measles virus during 1999 to 2008 was amplified, using the RT-PCR Assay. PCR products were sequenced and compared with the sequences of measles vaccine and other epidemic strains. RESULTS: Totally, 1524 nucleotides were sequenced from each epidemic strain and 507 amino acids were derived correspondingly. Compared with the vaccine strain, there were 59 - 75 nucleotides (divergent ratios were 3.9% - 4.9%) mutated from the epidemic strains, which were isolated during 1999 to 2008 and causing mutation on 36 - 42 amino acid (divergent ratios were 7.1% - 8.3%). Changes were also observed on the secondary structure. The phylogenetic tree, constructed based on the sequences of P gene, was similar to that based on the N gene, recommended by WHO. In addition, the average divergent ratio of P protein was greater than the ratio occurred on the N and H genes. CONCLUSION: The variation within the P gene between the vaccine and epidemic strains circulated in Zhejiang province during 1999 to 2008 was significant.

[Traceability of the A/H3N2 virus borne influenza pandemic in Zhejiang province, 1998].

OBJECTIVE: To trace back to the influenza pandemic caused by A/H3N2 virus happened in Zhejiang province, 1998. METHODS: The whole genome of three isolates related to Zhejiang influenza virus was amplified through RT-PCR, and the identified sequences were aligned with the sequences downloaded from GenBank of the H3N2 strains which were circulating in other regions during 1995 to 1998. The crossing HAI titers of the reference strains were measured by HAI test and antigenic ratios were calculated. RESULTS: The Phylogenetic tree, constructed based on HA sequence showed that the dominant strains A/Zhejiang/11/98 and A/Zhejiang/18/98 were significant different from the isolates circulated in other regions during 1995 to 1996 and the strains isolated in the mainland of China, in 1997. Although the A/Zhejiang/11/98 and A/Zhejiang/18/98 strains were distributed in the same cluster with A/Sydney/5/97, the two strains were closer to the epidemic strains isolated in Hong Kong and New York in the later part of 1997. Based on HA1, NA and MP genes, A/Zhejiang/18/98 seemed to be the closest one to the Hong Kong epidemic strains, and the genetic distances between A/Zhejiang/18/98 and New York strains were shorter than that with A/Sydney/5/97 based on PA, HA and NS genes. There were only 1 - 3 amino acid differences between A/Zhejiang/18/98 and Hong Kong or New York strains, whereas 7 amino acid differences with A/Sydney/5/97, in which three were located in the antigenic determinant regions. Data from the crossing HAI test showed that the antigenic ratio between A/Zhejiang/18/98 and A/Sydney/5/97 had reached 2.0, indicating the antigenic difference to a certain extent. Additionally, the onset of the influenza epidemic during 1997 to 1998 also suggested the possible route of transmission related to this H3N2 virus. CONCLUSION: The influenza pandemic occurred in Zhejiang province in 1998 was possibly caused by the importation of a newly identified H3N2 influenza variant via Hong Kong and New York in late 1997.