Fabrication of Ag2O/Ag decorated ZnAl-layered double hydroxide with enhanced visible light photocatalytic activity for tetracycline degradation.

The photocatalytic performance of layered double hydroxides (LDH) is usually confined to the slow interface mobility and high recombination rate of photogenerated electron-hole pairs in material. To overcome the low photocatalytic efficiency, novel Ag2O/Ag decorated LDH (LDH-Ag2O/Ag) was successfully synthesized by depositing Ag2O on the surface of LDH and then converted to Ag° nanoparticles in the right position after heat treatment. The as-synthesized LDH-Ag2O/Ag composites were characterized by Powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL) and transient photocurrent (TPC) analysis. Compared with virgin LDH, the photocatalytic activities of LDH-Ag2O/Ag composites were enhanced significantly. The optimum photocatalytic efficiency of LDH-Ag10 (0.0184 min-1) was nearly 46 times higher than that of virgin LDH (0.0004 min-1). The result of active species trapping experiments indicated that •OH, h+, and •O2- have an effect on the TC degradation, where •OH played the predominant role during the photocatalytic process. The possible photocatalytic mechanisms involving the charge transfer pathway and reactive species generation during the process of TC degradation were also discussed. The improved photocatalytic activity of LDH-Ag2O/Ag could be attributed to the synergetic effect between LDH and Ag2O/Ag that extended visible light range and reduced photogenerated charge carriers recombination.

Facile Preparation of Modifying Layered Double Hydroxide Nanoparticles for Drug Delivery.

Mg-Al-NO3 hydrotalcite (p-LDH) was employed as a carrier for the controlled release of 5-Fluorouracil (5-FU). The p-LDH was pretreated by acid-pretreatment to gain a more stable material (a-LDH) in acid medium for oral administration. It demonstrated that the a-LDH had smaller crystal size, particle sizes and higher permanent charge density (σp) compared with that of the p-LDH by means of XRD, SEM, FT-IR, UV-vis DRS, TG-DSC, BET/BJH and other techniques. The FU/a-LDH and FU/p-LDH delivery systems were obtained using anion-exchange method. The in vitro 5-FU drug release studies showed that no burst release phenomenon was observed at the beginning of release tests. The in vitro 5-FU release behaviors of the delivery systems at initial pH 4.6 and 7.5 were studied which could be described by first-order and Bhaskas models. Combined with the XRD and FT-IR analyses of the solid residues of the FU/a-LDH and FU/p-LDH after the release, it was found that the dissolution mechanism was mainly responsible for the release behavior of the FU/p-LDH at initial 4.6, while the anion-exchange between intercalated 5-FU and phosphate anions mechanism was responsible for the FU/a-LDH at pH 4.6 and 7.5 as well as FU/p-LDH at pH 7.5. It is concluded that the hydrotalcites could be used as the basis of a tunable drug delivery carrier for 5-FU.

Low NKD1 expression predicts adverse prognosis in cytogenetically normal acute myeloid leukemia.

Dysregulation of NKD1 has been identified in several solid tumors. However, the status of NKD1 expression and its clinical implication in acute myeloid leukemia remain largely elusive. NKD1 transcript level in bone marrow mononuclear cells was detected by real-time quantitative polymerase chain reaction in 126 de novo acute myeloid leukemia patients and 30 controls. Clinical significance of NKD1 expression was obtained by the comparison between the patients with low and high NKD1 expression. NKD1 messenger RNA level was significantly decreased in acute myeloid leukemia patients compared with controls ( p = 0.019). There were no significant differences between patients with low and high NKD1 expression in sex, age, peripheral blood cells, bone marrow blasts, French-American-British/World Health Organization subtypes, and karyotypes/karyotypic classifications ( p > 0.05). Although no significant difference was observed in complete remission rate between NKD1low and NKD1high patients ( p > 0.05), Kaplan-Meier analysis revealed that NKD1low patients showed shorter overall survival time than NKD1high patients in whole-cohort acute myeloid leukemia, non-M3 acute myeloid leukemia, and cytogenetically normal acute myeloid leukemia ( p = 0.014, 0.063, and 0.020). Multivariate analyses disclosed the low NKD1 expression was an independent risk factor in cytogenetically normal acute myeloid leukemia patients (hazard ratio = 0.397, p = 0.017). Moreover, the prognostic value of NKD1 expression was confirmed by gene expression profile data in cytogenetically normal acute myeloid leukemia patients ( p = 0.028 and 0.011). NKD1 showed significantly increased level after induction chemotherapy achieved complete remission in follow-up paired acute myeloid leukemia patients ( p < 0.001). These findings indicated that reduced NKD1 expression is associated with unfavorable clinical outcome in cytogenetically normal acute myeloid leukemia.

The prognostic implication of SRSF2 mutations in Chinese patients with acute myeloid leukemia.

Recently, somatic mutations in SRSF2 gene have been discovered in a proportion of hematologic malignancies including acute myeloid leukemia (AML). This study was aimed to investigate SRSF2 mutations in Chinese AML patients. High-resolution melting analysis (HRMA) was developed to screen SRSF2 mutations in 249 cases with AML, and then direct DNA sequencing was used to verify the results of HRMA. In this study, 3.6 % (9/249) of Chinese AML patients were found with heterozygous SRSF2 mutations. Patients with SRSF2 mutations were older than those with wild-type SRSF2 (P = 0.014). No differences in the sex, blood parameters, French-American-British classification (FAB) subtypes, and karyotypes were observed between AML patients with and without SRSF2 mutations. Although the overall survival (OS) of SRSF2-mutated patients was inferior to those without mutations in both whole AML patients (median 4 vs. 11 months, respectively; P = 0.006) and cytogenetically normal patients (median 2 vs. 12 months, respectively; P = 0.008), multiple analysis disclosed that SRSF2 mutation was not an independent prognostic factor in AML patients. These results suggest that SRSF2 mutation occurs at a low frequency in aged AML patients and might not be associated with adverse prognosis in Chinese AML patients.

[Human papillomavirus genotypes in male patients attending the STD clinic in Zhenjiang area].

OBJECTIVE: To investigate the status of human papillomavirus ( HPV) infection and its genotypes in male patients in Zhenjiang area. METHODS: Using PCR and reverse dot blot hybridization, we determined the genotypes of HPV DNA in 245 male patients at our Clinic of Dermatology and STD. RESULTS: The total rate of HPV infection was 43.67% (107/245), and 18 subtypes were detected. Among the 107 HPV-positive cases, low-risk, high-risk, and combined high- and low-risk infections accounted for 39.25% (42/107), 38.32% (41/107), and 22.43% (24/107), respectively. The most notable low-risk HPV types were HPV6 and HPV11, and the most notable high-risk HPV types were HPV16, HPV52, and HPV58. The rates of single infection and multi-infection were 53.27% (57/107) and 46.73% (50/107), respectively. One case had the most types, infected with 8 genotypes. No statistically significant differences were observed in the total rate of HPV infection among different age groups (Χ2 = 7.999, P > 0.05). CONCLUSION: The dominant subtypes of HPV infection in male patients in Zhenjiang area were HPV6, HPV11, and HPV16. The most common subtypes were HPV6 and HPV11 in low-risk infection, and HPV16, HPV52, and HPV58 in high-risk infection.

IDH1 and IDH2 mutation analysis in Chinese patients with acute myeloid leukemia and myelodysplastic syndrome.

The somatic mutations of isocitrate dehydrogenase genes (IDH1 and IDH2) have been identified in a proportion of hematologic malignancies. We examined IDH1 R132 and IDH2 R140/R172 mutations by high resolution melting analysis and direct sequencing in Chinese patients with different myeloid malignancies including 198 acute myeloid leukemia (AML), 82 myelodysplastic syndrome (MDS), 85 chronic myeloid leukemia, and 57 myeloproliferative neoplasms. IDH1 and IDH2 mutations were found in four (2.0%) and ten (5.0%) AML and in two (2.4%) and three (3.6%) MDS cases, but not in other patients. IDH1 and IDH2 mutations were heterozygous and mutually exclusive. IDH1/2 mutations were significantly more frequently observed in cytogenetically normal AML or MDS compared to those without mutations. There was no difference in overall survival of both AML and MDS patients with or without IDH1/2 mutations (P = 0.177 and 0.407, respectively). In conclusion, IDH1/2 mutations are recurrent but rare molecular aberrations in Chinese AML and MDS.

[Detection of NPM1 Mutation in Acute Myeloid Leukemia by Droplet Digital PCR and Its Clinical Application Value].

OBJECTIVE: To establish the droplet digital PCR (ddPCR) assay for the detection of NPM1 type A mutation in patients with acute myeloid leukemia (AML), and to evaluate its specificity, sensitivity and its value in clinical application. METHODS: NPM1 mutant and wildtype plasmids were used to verify the performance of ddPCR. Both ddPCR and Sanger sequencing were used to detect the bone marrow samples of 87 AML patients, which were confirmed by next generation sequencing (NGS). Moreover, NPM1 mutation burden was dynamically monitored in five patients by ddPCR. RESULTS: The limit of blank (LOB) of ddPCR established for NPM1 mutation detection was 1.1 copies/µl, and the limit of detection (LOD) was 2.43 copies/µl, which had good linearity. Among the 87 newly diagnosed AML patients, ddPCR identified seventeen cases positive for NPM1 mutation (19.5%)， which was consistent with Sanger sequencing. NGS confirmed 12 positive cases, including 8 of type A mutations, 2 of type D mutations, and 2 of rare type mutations. The results of dynamic monitoring of NPM1 mutation burden in 5 patients showed that the NPM1 mutation burden decreased obviously even close to 0, when patients achieve complete remission after chemotherapy. However, the mutation burden was increased again at the time of relapse. CONCLUSION: In this study, we established a ddPCR method for detection of NPM1 mutation with good sensitivity and repeatability, which can be used for screening NPM1 mutation in newly diagnosed AML patients and for minimal residual disease monitoring after remission in positive AML patients to guide treatment.

Detection of the JAK2 mutation in myeloproliferative neoplasms by asymmetric PCR with unlabeled probe and high-resolution melt analysis.

BACKGROUND: Several methods have been established to detect the JAK2 V617F mutation, a frequent event involved in the pathogenesis of myeloproliferative neoplasms (MPNs). High-resolution melt (HRM) analysis is a newly established technique without the requirement of any gel-based post-PCR handling. METHODS: An asymmetric PCR with unlabeled specific probe was developed and combined to HRM analysis o screen for JAK2 V617F mutation. RESULTS: Heterozygous mutation was easily distinguished from homozygous JAK2 for the obvious shape change. Homozygous JAK2 mutant can be also well separated from wild-type JAK2 in the presence of internal temperature calibrators. The easily recognizable and maximal sensitivity of HRM analysis was 5% for the detection of JAK2 V617F mutation, higher than 25% of direct sequencing. In the test of blind screening of 223 samples (111 Ph- MPNs, 60 Ph+ chronic myeloid leukemia, and 52 acute myeloid leukemia), JAK2 V617F mutations were found in 78 (70%) patients with MPNs, but in none with chronic and acute myeloid leukemia. HRM analysis of all cases was fully concordant with the results of PCR-RFLP and direct sequencing. CONCLUSIONS: The HRM method with unlabeled probe could be used as convenient, sensitive and reliable diagnostic test for detection of JAK2 V617F mutation.

[Quantification of GRAF gene expression in patients with acute myeloid leukemia using EvaGreen real time quantitative PCR].

OBJECTIVE: To quantify the expression level of GRAF gene in acute myeloid leukemia (AML) and analyze its clinical significance. METHODS: The EvaGreen real-time quantitative polymerase chain reaction (RQ-PCR) assay was established and performed to measure the GRAF gene transcripts in 71 cases with AML and 21 with nonmalignant hematological diseases. The clinical correlation of GRAF expression was analyzed. RESULTS: The established EvaGreen RQ-PCR assay had good specificity, reproducibility and sensitivity. The GRAF expression level was significantly lower in AML (0.01%-169.75%, median 3.82%) than that in controls (14.49%-126.85%, median 56.04%) (P<0.05). There was no correlation between the level of GRAF transcript and the sex, age, hematologic parameters, FAB subtypes and karyotypic groups (P>0.05). CONCLUSION: The GRAF gene was down-regulated in AML, which might play a role in the leukemogenesis.

Hydrogen peroxide biosensor based on chitosan/2D layered double hydroxide composite for the determination of H2O2.

The composites (LDH-CMC) composed of carboxymethyl chitosan (CMC) and 2D ZnAl layered double hydroxide (LDH) were successfully prepared using the one-step urea method; these composites were characterized by XRD, FT-IR, UV-vis DRS, SEM, BJH/BET, TG-DTG and pHzpc analyses, cyclic voltammetry, and electrochemical impedance spectroscopy. The use of CMC could impact the textural and surface chemical properties of the LDH-CMC composites, where the composites still maintained the 2D layered structure. Incorporating a moderate amount of CMC could increase both the surface area and the permanent charge density of the composites, leading to improved electrochemical performances. The LDH-CMC composite was used as a support matrix for the immobilization of horseradish peroxidase (HRP) on the glass carbon (GC) electrode to construct a biosensor that provides a biocompatible microenvironment for HRP and a pathway for H2O2 diffusion via the high surface area. The HRP biosensor displayed a satisfactory sensitivity and fast response (<3 s) toward H2O2 over a wide linear range of 0.02-6.0 mmol·L-1 with a low detection limit of 12.4 µmol·L-1, good anti-interference ability and long-term storage stability. The proposed HRP biosensor was found to be a sensitive, rapid, and disposable sensor with low cost, easy preparation and high selectivity; thus, the proposed biosensor can be used for the real-time detection of trace H2O2 in the biological, clinical and environmental fields.

Overexpression of lncRNA PANDAR predicts adverse prognosis in acute myeloid leukemia.

BACKGROUND AND PURPOSE: Abundant studies have shown that lncRNA PANDAR plays an oncogenic role in human solid tumors. Although abnormal expression of PANDAR has been well investigated in solid tumors, it was rarely studied in hematologic diseases. Hence, the aim of this study was to determine the PANDAR expression level and its clinical significance in patients with acute myeloid leukemia (AML). MATERIALS AND METHODS: For detecting the expression level of PANDAR in 119 AML patients and 26 controls, real-time quantitative PCR was used in this study. The prognostic values were evaluated by using Kaplan-Meier analysis, Cox regression analyses, and logistic regression analysis. RESULTS: PANDAR was significantly overexpressed in AML and might be a promising biomarker which could distinguish AML from normal samples (P<0.001). Patients with high expression of PANDAR (PANDAR high) were older and showed higher bone marrow blasts than patients in PANDAR low group (P=0.029 and 0.032, respectively). Significant differences between these groups were also detected regarding risk group and karyotype finding (P=0.009 and 0.041, respectively). Importantly, PANDAR high patients presented a significant lower complete remission rate compared to PANDAR low patients (P<0.001). Furthermore, Kaplan-Meier analysis showed that PANDAR high patients had shorter overall survival compared to PANDAR low patients observing the whole AML cohort, and also in the non-M3 group of patients (P<0.001 and P=0.005, respectively). Multivariate analysis of Cox and logistic regression analysis confirmed that high PANDAR expression was an independent unfavorable risk factor for overall survival and complete remission in both observed patient groups. CONCLUSION: These results revealed that PANDAR was overexpressed in AML, and that higher PANDAR expression was associated with poor clinical outcome. Our study therefore suggests that PANDAR expression is a promising biomarker for prognostic prediction for AML.

BP1 overexpression is associated with adverse prognosis in de novo acute myeloid leukemia.

To investigate DLX4 isoforms expression and their clinical significance in acute myeloid leukemia (AML). DLX4 transcript variant 1 (BP1) expression was significantly up-regulated in AML patients compared with normal controls. However, DLX4 transcript variant 2 (DLX7) was significantly down-regulated in AML patients. Both in the overall AML and the non-M3 AML cohorts, those patients with high BP1 expression (BP1(high)) showed significantly lower rates of complete remission than those with low BP1 expression (BP1(low)). BP1(high) cases had significantly shorter overall survival than BP1(low) cases in the overall AML cohort, non-M3 AML, and cytogenetically normal AML (CN-AML). Multivariate analysis confirmed the independent prognostic value of BP1 expression among both the overall AML cohort and non-M3 AML as well as CN-AML patients. However, we did not observe the impact of DLX7 expression on prognosis in AML patients. Our study reveals that BP1 overexpression serves as an independent risk factor in de novo AML patients.

Double CEBPA mutations are prognostically favorable in non-M3 acute myeloid leukemia patients with wild-type NPM1 and FLT3-ITD.

This study is aimed to investigate the pattern of CEBPA mutations and its clinical significance in Chinese non-M3 acute myeloid leukemia (AML) patients. The entire coding region of CEBPA gene was amplified by PCR and then sequenced in samples from 233 non-M3 AML patients. Fifty mutations were identified in 37 (15.8%) patients with eleven (4.7%) double mutated CEBPA (dmCEBPA) and twenty-six (11.1%) single mutated CEBPA (smCEBPA). dmCEBPA was exclusively observed in M1 and M2 subtypes of FAB classification (P = 0.008), whereas smCEBPA occurred in almost all subtypes (P = 0.401). Patients with dmCEBPA had significantly younger age and higher WBC counts than those with wtCEBPA (P = 0.016 and 0.043, respectively). Both dmCEBPA and smCEBPA were mainly present in cytogenetically normal patients. Patients with dmCEBPA achieved higher rate of complete (CR) than wtCEBPA patients (88% vs. 51%, P = 0.037), whereas smCEBPA and wtCEBPA groups are similar (47% vs. 51%, P = 0.810). Patients with dmCEBPA had a superior overall survival (OS) compared with patients with wtCEBPA (P = 0.033), whereas patients with smCEBPA had a similar OS as patients with wtCEBPA (P = 0.976). dmCEBPA but not smCEBPA was also associated with favorable outcome in patients with wild-type NPM1 and FLT3-ITD (NPM1(wt)FLT3-ITD(wt) ). Our data confirm that dmCEBPA but not smCEBPA is prognostically favorable in NPM1(wt)FLT3-ITD(wt) AML, and suggest that the entity AML with mutated CEBPA should be definitely designated as AML with dmCEBPA in WHO classification and smCEBPA should be excluded from the favorable risk of molecular abnormalities.

Development of a high-resolution melting analysis for the detection of the SF3B1 mutations.

SF3B1, located on chromosome 2q33.1, encodes a core component of RNA-splicing machinery, and its mutation has been described in myelodysplastic syndromes (MDS) characterized with ring sideroblasts (RS). To explore the reliability and sensitivity of the high-resolution melting analysis (HRMA) technique for the identification of the SF3B1 mutations, mutations in 92 patients with MDS were detected in this study. The sensitivity could reach 5%, obviously higher than the 25% of direct DNA sequencing. A low frequency (5.4%) of SF3B1 mutations were identified in patients with MDS, including three cases of K700E, one case of H662Q, and one case of K666M. Further, SF3B1 mutations were more frequently recurrent in the 33% of patients with MDS characterized with RS, whereas in other subtypes of MDS, only 2.3% of patients were detected with SF3B1 mutations (p=0.006). In conclusion, a rapid, reproducible, sensitive, and high-throughput HRMA assay has been established for the scanning of SF3B1 mutations.

SF3B1 mutation is a rare event in Chinese patients with acute and chronic myeloid leukemia.

OBJECTIVE: Somatic mutations of SF3B1 gene have recently been identified in myelodysplastic syndrome and chronic lymphocytic leukemia. The frequency and clinical relevance of SF3B1 mutations have been rarely studied in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). The present study was aimed to analyze the frequency of SF3B1 mutations in AML and CML. DESIGNS AND METHODS: High-resolution melting analysis (HRMA) was established to detect the mutation hotspots (codon E622, H662, K666, and K700) of SF3B1 gene in 275 AML and 81 CML patients. RESULTS: Heterozygous SF3B1 mutations were detected in three AML patients by HRMA. Direct DNA sequencing identified one K666T, one K666N and one K700E mutations. All three AML patients had normal karyotypes. One case also had NPM1 and DNMT3A mutations, one had FLT3 internal tandem duplication and DNMT3A mutations, and the other had NPM1 mutation. No SF3B1 mutations were detected in CML patients. CONCLUSIONS: SF3B1 mutation is a rare molecular event in Chinese AML and CML patients.

Development of high-resolution melting analysis for the detection of the MYD88 L265P mutation.

OBJECTIVE: Recurrent L265P mutation of myeloid differentiation primary response gene 88 (MYD88) has been identified in a proportion of diffuse large B-cell lymphoma (DLBCL) and chronic lymphocytic leukemia. The present study aimed to establish a rapid, sensitive, and reliable method using high-resolution melting analysis (HRMA) to detect MYD88 L265P mutation in DLBCL. DESIGNS AND METHODS: The sensitivity of HRMA in the detection of MYD88 L265P mutation was evaluated. MYD88 L265P mutation was further screened in 120 patients with DLBCL. The results of HRMA were validated by direct DNA sequencing. RESULTS: For the detection of MYD88 L265P mutation, the reproducible maximal sensitivity of HRMA was 5% higher than that obtained by direct DNA sequencing (25%). Heterozygous MYD88 L265P mutations were identified in 11 (9.2%) DLBCL cases, all of which were diagnosed as non-germinal-center B cell (non-GCB) DLBCL. CONCLUSIONS: The HRMA assay is a rapid, sensitive, reliable, and high-throughput method to screen MYD88 L265P mutation and could be used in clinical diagnostic laboratories.

Rapid and reliable detection of IDH1 R132 mutations in acute myeloid leukemia using high-resolution melting curve analysis.

OBJECTIVE: The mutations of isocitrate dehydrogenase 1 (IDH1) gene have been identified in a proportion of hematologic malignancies including acute myeloid leukemia (AML). The aim of the present study was to explore the reliability of the high-resolution melting analysis (HRMA) for the identification of IDH1 R132 mutations in AML. DESIGNS AND METHODS: We evaluated the sensitivity of HRMA in the detection of IDH1 R132 mutation and screened IDH1 mutations in 110 AML patients using HRMA. The results of HRMA were validated by direct DNA sequencing. RESULTS: The reproducible sensitivity of HRMA was 5% for the detection of IDH1 R132 mutation, higher than 10% of direct DNA sequencing. Heterozygous IDH1 mutations were identified in 4 (3.6%) AML cases, which were R132H in 3 cases and R132S in 1 case confirmed by DNA sequencing. CONCLUSION: The HRMA is a rapid, accurate, reliable, high-throughput method to screen IDH1 gene mutations.

Abnormal methylation of GRAF promoter Chinese patients with acute myeloid leukemia.

The epigenetic disturbances are recognized as an alternative mechanism contributing to the pathogenesis of acute myeloid leukemia (AML). GTPase regulator associated with focal adhesion kinase (GRAF), a putative tumor suppressor gene, was revealed with mutations and promoter methylation in AML and myelodysplastic syndrome. In this study, we investigated the methylation status of GRAF promoter in Chinese AML patients. Aberrant methylation of GRAF promoter was detected in 66.7% (88/132) of the cases analyzed. The methylation of GRAF gene could be detected in all FAB subtypes and in all cytogenetic risk groups. There were no significant differences in clinical features, FAB subtypes and cytogenetic risk groups between patients with and without GRAF methylation. GRAF transcript was significantly lower in AML group compared to controls (3.30 vs 56.06, P<0.001). Both patients with methylated GRAF gene and those without methylated GRAF gene had significantly lower GRAF transcript than controls (P<0.001). Furthermore, GRAF transcript was significantly lower in patients with methylated GRAF than those without methylated GRAF (1.64 vs 6.42, P=0.005). These findings suggest that the hypermethylation of GRAF promoter might be one of early events in the development of AML.

[Scanning of c-kit gene mutations in acute myeloid leukemias using high-resolution melting analysis].

OBJECTIVE: To detect the common mutations (D816V and N822K) of c-kit gene in acute myeloid leukemia (AML) using high-resolution melting analysis (HRM). METHODS: HRM analysis was established to screen c-kit mutations in PCR products of c-kit exon 17 in 21 AML patients with t(8;21). PCR products were sequenced to confirm the mutation. RESULTS: HRM analysis identified an aberrant melting curve in 6 cases (28.6%), which were confirmed by direct DNA sequencing as one D816V mutation and five N822K mutation. CONCLUSION: HRM analysis is a convenient, rapid, specific and high-throughput technique for scanning c-kit gene mutation in AML.