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This paper reports on a colorimetric assay for H2O2 and glucose. It is based on the use of human serum albumin-templated MnO2 nanosheets that possess oxidase-like activity. They are capable of oxidizing 3,3',5,5'-tetramethylbenzidine (TMB) with oxygen to give a blue product (oxTMB) with an absorbance maximum at 652 nm. When H2O2 is introduced, the MnO2 nanosheets are reduced to Mn(II) ions, and this inhibits the formation of oxTMB. Based on these findings, a colorimetric assay was established for H2O2 that has a 0.56 μM detection limit. If glucose is oxidized by glucose oxidase under formation of H2O2, the nanosheets can be used to quantify H2O2 and thereby to sense glucose. Response is linear in the 0.5 μM to 50 μM glucose concentration range, and the detection limit is 0.32 μM. The method was applied to the determination of glucose in spiked serum samples and gave satisficatory results.Human serum albumin (HSA) is used as a template for the synthesis of MnO2 nanosheet. These possess oxidase mimicking activity. H2O2 can reduce the nanosheets. The effect is exploited in colorimetric assays for H2O2 and glucose using tetramethylbenzidine (TMB) as a chromogenic substrate. [ABSTRACT FROM AUTHOR]

Objective: To analyze the clinical characteristics and risk factors of invasive fungal infection (IFI) occurenced in patients with acute leukemia (AL) during treatment in tropical regions., Methods: The clinical data of 68 AL patients admitted to the Hainan Hospital of PLA General Hospital from April 2012 to April 2019 was retrospectively analyzed. Logistic regression analysis was used to analyze the factors affecting the occurrence of IFI in AL patients., Results: Among the 68 patients, 44 were acute myeloid leukemia, 24 were acute lymphoblastic leukemia, 39 were male, 29 were female and the median age was 41(13-75) years old. The 68 patients received 242 times of chemotherapy or hematopoietic stem cell transplantation(HSCT), including 73 times of initial chemotherapy or inducting chemotherapy after recurrence, 14 times of HSCT, 155 times of consolidating chemotherapy. Patients received 152 times of anti-fungal prophylaxis, including 77 times of primary anti-fungal prophylaxis and 75 times of secondary anti-fungal prophylaxis. Finally, the incidence of IFI was 31 times, including 24 times of probable diagnosis, 7 times of proven diagnosis, and the total incidence of IFI was 12.8%(31/242), the incidence of IFI in inducting chemotherapy was 24.66%(18/73), the incidence of IFI in HSCT patients was 28.57% (4/14), the incidence of IFI in consolidating chemotherapy was 5.80% (9/155). Multivariate analysis showed that inducting chemotherapy or HSCT, the time of agranulocytosis ≥7 days, risk stratification of high risk were the independent risk factors for IFI in AL patients during treatment in tropical regions., Conclusion: The incidence of IFI in patients with AL in the tropics regions is significantly higher than that in other regions at homeland and abroad. Anti-fungal prophylaxis should be given to the patients with AL who have the high risk factors of inducting chemotherapy or HSCT, time of agranulocytosis ≥7 days and risk stratification of high risk.

Objective: To analyze the characteristics, prognosis and risk factors of bloodstream infection in patients with hematological malignancies in the tropics, so as to provide evidence for the prevention and treatment of bloodstream infection., Methods: The clinical features, blood culture results and prognosis of patients with bloodstream infection in patients with hematological malignancies admitted to Hainan Hospital of PLA General Hospital were retrospectively studied., Results: The most common primary infection site of the 81 patients with hematological malignancies was lung (46.91%), followed by PICC (11.11%). The detection rate of Gram-positive bacteria and Gram-negative bacteria in the blood culture was 60.98% and 30.02%, respectively. Coagulase-negative staphylococci was the most common Gram-positive bacteria resulting in bloodstream infection in our study. Of the Gram-negatives, Klebsiella pneumoniae (34.38%) was predominant, followed by Escherichia coli (18.75%) and Pseudomonas aeruginosa (18.75%). Gram-positive bacteria was highly sensitive (100%) to vancomycin, linezolid and tigecycline. Study showed that Gram-negative bacteria had low sensitive to quinolones, in particular, the resistance rate of Escherichia coli to quinolones was as high as 83.33%. In terms of overall survival (OS), the 30-days OS of patients with Gram-negative and Gram-positive septicemia was 77.42% and 92.00%, respectively. There was no statistically significant difference between the two groups. Multivariate analysis revealed that septic shock (P=0.001, RR=269.27) was an independent risk factor for 30-day mortality, and remission status (P=0.027, RR=0.114) was an independent predictor of a favourable outcome of bloodstream infection in patients with hematological malignancies., Conclusion: Gram-positive bacteria are the main pathogens causing bloodstream infections in patients with hematological malignancies in the tropics. Improving the care of PICC is an important measure to reduce the incidence of bloodstream infection in patients with hematological malignancies in the tropics. A correct treatment relieving disease and effective prevention and treatment of septic shock can reduce mortality of patients with bloodstream infection in patients with hematological malignancies in the tropics.

Objective: To investigate the incidence, clinical features of U2AF1 gene mutation in patients with acute myeloid leukemia(AML) and its effect of prognosis., Methods: A total of 161 patients with AML were enrolled. The second-generation sequencing method was used to detect U2AF1 gene mutation, and the relationship between U2AF1 mutation and clinical features, prognosis was analyzed., Results: The mutation rate of U2AF1 gene in 161 AML patients was 3.73%. The counts of peripheral blood leukocytes and platelets in the U2AF1 gene mutation group were lower than those in the wild type group. The complete response rate of U2AF1 gene mutation group was 66.67%, while that in wild type group was 55.48%, which shows no significant difference between the two groups (P=0.70). The median EFS of wild type group and the mutant group was not reached and reached to 133 days, respectively (P=0.03), while the medium OS in two groups was not reached and reached to 210 days (P=0.01)., Conclusion: The AML patients with U2AF1 mutation positive have a poor prognosis as compared with the wild type group, which may be a poor prognostic factor for acute myeloid leukemia.