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Objective: To compare and analyze the clinical characteristics of acute myeloid leukemia (AML) related to the treatment of hematological tumors and solid tumors. Methods: The laboratory and clinical data of 41 patients with treatment-related AML (t-AML) in the Department of Hematology, Henan Cancer Hospital from January 2014 to December 2021 were retrospectively analyzed, and they were divided into hematological tumor group and solid tumor group. Survival analysis was performed using the Kaplan-Meier method and Log rank test. Results: The median interval from the first tumor diagnosis to t-AML in 41 patients was 21.0 (16.5-46.0) months; 24 (58.5%) had abnormal expression of lymphoid antigen, 28 (68.3%) had abnormal karyotype, 18 cases (43.9%) were positive for fusion gene, and 28 cases (68.3%) were positive for gene mutation; the median recurrence-free survival (RFS) was 11.0 months, and the median overall survival (OS) was 11.5 months. The proportion of acute promyelocytic leukemia ([APL], 0.0, 0/13), complete response ([CR],18.2%, 2/11), median OS (4.5 months) and median RFS (2.5 months) of t-AML patients in the hematological tumor group were significantly lower than those in the solid tumor group (35.7%, 10/28; 68.0%, 17/25; not reach; not reach), but the proportion of M4 /M5 (93.2%,12/13) was significantly higher than that in the solid tumor group (53.6%,15/18; all P values<0.05). Through subgroup analysis, the proportion of patients with positive PML-RARa and good prognosis karyotypes in the solid tumor group (35.7%, 10/28; 46.4%, 13/28) was significantly higher than that in the hematological tumor group (0.0, 0/13; 0.0, 0/13; P<0.05), while the proportion of patients with intermediate karyotypes (42.9%, 12/28) was significantly lower than that in the hematological tumor group (84.6%, 11/13; P<0.05), the difference was statistically significant. The CR rate (90.0%, 9/10), median OS (not reach) and median RFS (not reach) in the t-APL group were higher than those in the t-AML (without t-APL) group (38.5%, 10/26; 6 months; 8 months; P<0.05). After excluding the effect of t-APL patients, there was no significant difference in the CR rate, median OS and median RFS between the solid tumor group (8; 9 months; not reach) and the hematological tumor group (2; 4 months; 2 months; P>0.05). Univariate analysis showed that the primary tumor belongs to hematological tumor was a common risk factor for OS and RFS in t-AML patients (P<0.10). Conclusions: Compared with patients with t-AML secondary to solid tumors, patients with t-AML secondary to hematological tumors have poorer treatment effects and poorer prognosis. After excluding the effect of t-APL patients, there are no significant differences in the treatment efficacy and prognosis between the two types of t-AML patients.

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Objective: To compare and analyze the clinical characteristics of acute myeloid leukemia (AML) related to the treatment of hematological tumors and solid tumors. Methods: The laboratory and clinical data of 41 patients with treatment-related AML (t-AML) in the Department of Hematology, Henan Cancer Hospital from January 2014 to December 2021 were retrospectively analyzed, and they were divided into hematological tumor group and solid tumor group. Survival analysis was performed using the Kaplan-Meier method and Log rank test. Results: The median interval from the first tumor diagnosis to t-AML in 41 patients was 21.0 (16.5-46.0) months; 24 (58.5%) had abnormal expression of lymphoid antigen, 28 (68.3%) had abnormal karyotype, 18 cases (43.9%) were positive for fusion gene, and 28 cases (68.3%) were positive for gene mutation; the median recurrence-free survival (RFS) was 11.0 months, and the median overall survival (OS) was 11.5 months. The proportion of acute promyelocytic leukemia ([APL], 0.0, 0/13), complete response ([CR],18.2%, 2/11), median OS (4.5 months) and median RFS (2.5 months) of t-AML patients in the hematological tumor group were significantly lower than those in the solid tumor group (35.7%, 10/28; 68.0%, 17/25; not reach; not reach), but the proportion of M4 /M5 (93.2%,12/13) was significantly higher than that in the solid tumor group (53.6%,15/18; all P values<0.05). Through subgroup analysis, the proportion of patients with positive PML-RARa and good prognosis karyotypes in the solid tumor group (35.7%, 10/28; 46.4%, 13/28) was significantly higher than that in the hematological tumor group (0.0, 0/13; 0.0, 0/13; P<0.05), while the proportion of patients with intermediate karyotypes (42.9%, 12/28) was significantly lower than that in the hematological tumor group (84.6%, 11/13; P<0.05), the difference was statistically significant. The CR rate (90.0%, 9/10), median OS (not reach) and median RFS (not reach) in the t-APL group were higher than those in the t-AML (without t-APL) group (38.5%, 10/26; 6 months; 8 months; P<0.05). After excluding the effect of t-APL patients, there was no significant difference in the CR rate, median OS and median RFS between the solid tumor group (8; 9 months; not reach) and the hematological tumor group (2; 4 months; 2 months; P>0.05). Univariate analysis showed that the primary tumor belongs to hematological tumor was a common risk factor for OS and RFS in t-AML patients (P<0.10). Conclusions: Compared with patients with t-AML secondary to solid tumors, patients with t-AML secondary to hematological tumors have poorer treatment effects and poorer prognosis. After excluding the effect of t-APL patients, there are no significant differences in the treatment efficacy and prognosis between the two types of t-AML patients.

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OBJECTIVE: To study the application of Geographic Information System (GIS) electronic fence technique in Oncomelania hupensis snail monitoring. METHODS: The electronic fence was set around the history and existing snail environments in the electronic map, the information about snail monitoring and controlling was linked to the electronic fence, and the snail monitoring information system was established on these bases. The monitoring information was input through the computer and smart phone. RESULTS: The electronic fence around the history and existing snail environments was set in the electronic map (Baidu map), and the snail monitoring information system and smart phone APP were established. The monitoring information was input and upload real-time, and the snail monitoring information was demonstrated in real time on Baidu map. CONCLUSIONS: By using the electronic fence technology based on GIS, the unique "environment electronic archives" for each snail monitoring environment can be established in the electronic map, and real-time, dynamic monitoring and visual management can be realized.

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OBJECTIVE: To construct the Oncomelania hupensis snail monitoring system based on the Baidu Map. METHODS: The environmental basic information about historical snail environment and existing snail environment, etc. was collected with the monitoring data about different kinds of O. hupensis snails, and then the O. hupensis snail monitoring system was built. Geographic Information System (GIS) and the electronic fence technology and Application Program Interface (API) were applied to set up the electronic fence of the snail surveillance environments, and the electronic fence was connected to the database of the snail surveillance. RESULTS: The O. hupensis snail monitoring system based on the Baidu Map were built up, including three modules of O. hupensis Snail Monitoring Environmental Database, Dynamic Monitoring Platform and Electronic Map. The information about monitoring O. hupensis snails could be obtained through the computer and smartphone simultaneously. CONCLUSIONS: The O. hupensis snail monitoring system, which is based on Baidu Map, is a visible platform to follow the process of snailsearching and molluscaciding.

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Genome duplication in E. coli is carried out by DNA polymerase III, an enzyme complex consisting of ten subunits. Investigations of the biochemical and structural properties of DNA polymerase III require the expression and purification of subunits including α, ge, θ, γ, δ', δ, and β separately followed by in vitro reconstitution of the pol III core and clamp loader. Here we propose a new method for expressing and purifying DNA polymerase III components by utilizing a protein co-expression strategy. Our results show that the subunits of the pol III core and those of the clamp loader can be coexpressed and purified based on inherent interactions between the subunits. The resulting pol III core, clamp loader and sliding clamp can be reconstituted effectively to perform DNA polymerization. Our strategy considerably simplifies the expression and purification of DNA polymerase III and provides a feasible and convenient method for exploring other multi-subunit systems.

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E.coli single-stranded DNA-binding protein (SSB) plays an important role in replication, recombination and repair of DNA and is thus crucial for the survival of the bacteria.We described a high expression and efficient purification scheme and kinetic assay of interaction with its substrate, single-stranded DNA (ssDNA). A ssb gene (537 bp) for encoding SSB was obtained by PCR amplification from E.coli K-12 genome. The expression vector of the fusion protein SSB was constructed by attaching ssb gene to pQE30. SSB fusion protein was expressed in M15 E.coli strain induced by IPTG. SDS-PAGE analysis revealed that the expected protein with a molecular weight 20.6kDa was soluble and amounted to about 30% of the total bacterial protein. SSB protein was purified by immobilized metal (Ni2+) chelation affinity chromatography and the purity was about 90%. The resulting SSB protein was a correctly folded tetramer analyzed by gel filtration. It could bind ssDNA with equilibrium dissociation constant (KD) of 4.79×10-7 mol/L as determined by surface plasmon resonance.

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E.coli single-stranded DNA-binding protein (SSB) plays an important role in replication, recombination and repair of DNA and is thus crucial for the survival of the bacteria.We described a high expression and efficient purification scheme and kinetic assay of interaction with its substrate, single-stranded DNA (ssDNA). A ssb gene (537 bp) for encoding SSB was obtained by PCR amplification from E.coli K-12 genome. The expression vector of the fusion protein SSB was constructed by attaching ssb gene to pQE30. SSB fusion protein was expressed in M15 E.coli strain induced by IPTG. SDS-PAGE analysis revealed that the expected protein with a molecular weight 20.6kDa was soluble and amounted to about 30% of the total bacterial protein. SSB protein was purified by immobilized metal (Ni2+) chelation affinity chromatography and the purity was about 90%. The resulting SSB protein was a correctly folded tetramer analyzed by gel filtration. It could bind ssDNA with equilibrium dissociation constant (KD) of 4.79×10-7 mol/L as determined by surface plasmon resonance.

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Fusion tags are originally developed to facilitate the purification of recombinant protein from crude extracts. In recent years, the discovery of different tags and the development of fusion strategy make the function of fusion tags diversified. However, there was no a cure-all fusion tag for different applications. We here give an overview of fusion tag technology and the different applications of fusion tags, including the purification, detection and oriented immobilization of recombinant protein, the visualization of bioevent in vivo, the enhancement of the yield of protein, the improvement of the solubility and stability of the expressed protein.

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DNA mismatch repair gene mutS (2.56 kb) was PCR modified and cloned into a secretive prokaryotic expression vector pET32a (+) which carries a N-terminal His.tag + and thioredoxin sequence. MutS protein was expressed with high level after IPTG induction using the strain E. coli AD494(DE3). SDS-PAGE revealed that the expected protein with a molecular weight of 108 kD which is about 35% of the total bacterial proteins is almost soluble. The expected protein was purified directly by immobilized metal (Ni2+) chelation affinity chromatography and the purity is over 90%. MutS protein activity verified using mismatch DNA showed that the expression product can recognize and bind to base-pair mismatch specifically.

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