Bactericidal efficacy of five kinds of disinfectant on Staphylococcus aureus / 中国感染控制杂志

Objective To study the bactericidal efficacy of hospital commonly used disinfectants such as ethanol,3" chlorine tablets,iodophor,glutaraldehyde,and avagard instant hand antiseptic on Staphylococcus aureus (S.a ureus) from different sources of hospital,and provide scientific basis for effective control of healthcare-associated infection(HAI).Methods A total of 48 strains of S.aureus from inpatients,hands of health care workers,and environment surface in the First Affiliated Hospital of Nanchang University were collected.Disinfectant was directly contacted with bacteria,in vitro killing efficacy of disinfectant on S.aureus from different sources at different diluted concentrations,and different contact time were studied.Results The killing rate of 5g/L iodophor,20g/L glutaraldehyde,and avagard instant hand antiseptic(0.5％ chlorhexidine + 70％ ethanol) to S.aureus with a 5-minute contact time was 100％;killing rates of 70％ ethanol and 1g/L 3" chlorine tablets to S.aureus with a 5-minute contact time were 96.5 ％-99.8 ％;but highly diluted iodophor,glutaraldehyde,and avagard instant hand antiseptic still could not completely kill S.aureus even the contact time was extended.Conclusion The routine use of disinfectants in the hospital can meet the clinical bactericidal efficacy,it is necessary to monitor concentration routinely,avoid decreasing sterilization ability.

Signal Patterns of Dual Color Dual Fusion Fluorescence in Situ Hybridization for Detection of Genetic Abnormality in Adult Patients with ALL and Their Clinical Application / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To study the signal patterns of dual color dual fusion fluorescence in situ hybridization (DCDF-FISH) for detection of genetic abnormality in adult acute lymphoblastic leukemia (ALL) patients and their diagnostic value and clinical application.</p><p><b>METHODS</b>The clinical data of 68 ALL patients confirmed in our hospital were analyzed retrospectively; The bone marrow samples were detected by DCDF-FISH, flow cytometry, conventional cytogenetics (CCG), reverse transcriptase polymerase chain reaction (RT-PCR), and the correlation of these results was compared. And the reaction of patients to treatment was dynamically observed by DCDF-FISH.</p><p><b>RESULTS</b>Sixteen signal patterns were found in DCDF-FISH, including 14 kinds of atypical signal patterns (signal patterns of 1R2G, 2R3G, 2R4G and 3R3G as abnormal signal patterns without BCR/ABL fusion gene. Signal patterns of 1R1G1F, 1R1G3F, 1R1G4F, 1R2G1F, 1R2G2F, 1R2G3F, 1RnG2F (n ≥ 3), 2R2G1F, 1G4F, 1R4F corresponded to t (9;22) karyotype). Ph(+) ALL patients accounted for 17. All cases with Ph chromosome or BCR/ABL positive were B-ALL or My(+)-B-ALL. The Ph chromosome was detected in 12 cases (positive rate was 18%) by CCG. The positive rate was 25% (17/68) by DCDF-FISH and RT-PCR. The DCDF-FISH fluorescence pattern change before and after chemotherapy of the patients showed that the quantity and form of the signal pattern was changed after chemotherapy, and the common characteristics was the Ph chromosome in patients.</p><p><b>CONCLUSION</b>The DCDF-FISH is a sensitive and reliable method for the detection of BCR/ABL rearrangement. Analyzing the dynamical change of DCDF-FISH signal patterns has been comfirmed to have a important guiding significance in the diagnosis, and anlysis of response to therapy, drug resistance and the prognosis of ALL patients.</p>

Expression of CSN Complex in ATRA-induced APL Cell Differentiation and Its Clinical Significance / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression of CSN complex (COP9 signal some subunits) in the patients with acute promyelocytic leukemia (APL) and its significance in the ATRA-induced APL differentiation.</p><p><b>METHODS</b>Using the NB4 cells as a model, morphologic observation and myeloid differentiation marker CD11b detection were used to monitor ATRA-induced APL differentiation, the expression of CSN complex in cell differentiation was detected by Western blot and reverse transcription real time fluorescent quantitative PCR (RT-qPCR) method. RT-qPCR was also used to detect the relative expression level of COP9 signalosome subunits in the APL patients and remission after treatment.</p><p><b>RESULTS</b>ATRA could obviously enhance CD11b expression; the cell morphology showed obvious differentiation characteristics. During the differentiation, the expression of COP9 signalosome subunits was down-regulated by ATRA. Meanwhile, the CSN expression level in newly diagnosed APL patients was much higher than that in controls (non-leukemia) (P < 0.05). The level of CSN expression was obviously down-regulated when APL patients achieved complete remission.</p><p><b>CONCLUSION</b>The high CSN expression level in APL patients can be down-regulated by ATRA. CSN complex may have a significant effect on the pathogenesis and therapy of APL.</p>

Early monitoring drug-resistance of patients with BCR/ABL(+) ALL by DCDF-FISH / 中国实验血液学杂志

This study was aimed to investigate the application value of the dual color dual fusion fluorescence in situ hybridization (DCDF-FISH) in BCR/ABL (+) acute lymphoblastic leukemia patients with complex chromosomal translocation. The clinical presentations of a patient with ALL were monitored regularly by bone marrow cell morphology test, chromosome analysis, flow cytometry and DCDF-FISH technique, and the reaction of patients to treatment and disease progression were dynamically observed by DCDF-FISH. The results indicated that the patient showed the typical presentation of B lineage acute lymphoblastic leukemia (B-ALL) with expression of CD10, CD19 and CD34; the chromosome analysis showed 46,XY, i(8), ider(9)t (9; 22) [23]/47, idem, +der(22) t (9;22) [7] karyotype in the bone marrow cells, FISH showed that 83% cells contained BCR/ABL fusion gene in the patient's bone marrow, among which 5% cells showed 1R1G2F signalling model, 14% cells showed 1R1G3F, and 64% cells showed 1R1G4F. The patient got complete remission when the imatinib chemotherapy combined with VTLP was carried out, and the tumor cells decreased to 19%, but the cells with 1R1G2F signal model increased to 18%. The 1R1G2F cell signal model increased up to 38% when patient relapsed. The patient died of the drug-resistance. It is concluded that the BCR/ABL (+) leukemia patient with complex translocation has multiple tumor cell subsets, and the responses of different cell subsets to the treatment are different, therefore the response to therapy and drug resistance of patient can be monitored early by the signal model of DCDF-FISH and the observation of dynamical changes of different cell subset.

Effect of curcumin combined with ATRA on differentiation of ATRA-resistant acute promyelocytic leukemia cells / 中国实验血液学杂志

In order to investigate the effect of curcumin combined with all-trans retinoid acid (ATRA) on differentiation of ATRA-resistant acute promyelocytic leukemia (APL) cells and its molecular mechanism, the NB4-R1, an ATRA-resistant APL cells, was used as a model, counting of NB4-R1 and cell morphologic observation were performed, the effect of curcumin alone or combined with ATRA on proliferation, differentiation of NB4-R1 cells was detected by flow cytometry (FCM), the change of AKT phosphorylation in cell differentiation was detected by Western blot. The results showed that ATRA had no influence on NB4-R1 cell proliferation, but enhanced the inhibitory effect of curcumin on NB4-R1 cell growth; the curcumin or ATRA alone did not affect NB4-R1 differentiation; curcumin combined with ATRA could obviously induce CD11b expression; the cell morphology showed obvious differentiation characteristics. ATRA could promote phosphorylation of AKT in NB4 cells at short time, but not had effect on phosphorylation of AKT in NB4-R1 cells; the curcumin could enhance the phosphorylation of AKT in NB4-1R cells, the curcumin combined with ATRA could further enhance the phosphorylation of AKT. It is concluded that PI3K/AKT pathway inactivation may be one of the factors of drug resistance in APL and curcumin promotes differentiation of NB4-R1 through activating PI3K/AKT pathway.

ARMS-PCR method for detecting multiple NPM1 mutations / 中国实验血液学杂志

This study was aimed to establish a simple, sensitive detection method for multiple NPM1 mutations, so as to reduce the omission ratio of NMP1 mutant detection. Recombinant plasmids containing wide-type NPM1 and the most common mutations (A, B, C, D) were constructed as the detection objects. The ARMS-PCR for detecting multiple NPM1 mutations was established through designing a pair of specific primers whose 3' end base matched with four mutants (A,B,C,D), but did not matched with wild type NPM1 according to the different base sequence of NPM1 mutants. The feasibility of the ARMS-PCR method was evaluated by assessing the detection range and the sensitivity and comparing with direct sequencing. The results showed that the recombinant plasmids were constructed successfully by restriction analysis and DNA sequencing. The four mutants but not wild type NPM1 were detected by using ARMS-PCR, the detection range of the method was 10(3) copies/ml -10(9) copies/ml and the sensitivity was 0.01%, while the direct sequencing method could not detect the mutations if mutation was less than 10%. It is concluded that the high sensitive ARMS-PCR is established for detecting the four mutations of NPM1 and more than 95% mutants can be detected by this method, providing a new detection method for clinical NPM1 gene mutant.

Apoptosis of retinoic acid resistant NB4-R1 cells induced with curcumin and its mechanism / 中国实验血液学杂志

This study was purposed to explore the inhibitory effect of Curcumin on growth of retinoic acid-resistant acute promyelocytic leukemia (APL) cells and its mechanism. The NB4-R1, an APL cell line resistant to retinoic acid, was used as a model. The growth level of NB4-R1 was detected by MTT assay, the morphologic features of cells were observed by light microscopy, the mitochondrial transmembrane potential was determined by flow cytometry, the expressions of apoptosis-related proteins procaspase 3, caspase 3, PARP and BCL-XL were measured by Western blot. The results indicated that the sensitivity of NB4-R1 to Curcumin was consistent with NB4 though NB4-R1 was resistant to retinoic acid, Curcumin displayed inhibitory effect on growth of NB4-R1 in time-and concentration-dependent manners. The morphologic observation showed existence of apoptotic bodies in NB4-R1 cells treated with 20 micromol/L of Curcumin. The flow cytometry indicated that the mitochondrial transmembrane potential in NB4-R1 cells treated with 20 micromol/L of Curcumin obviously decreased. The Western blot detection revealed that expressions of pro-caspase 3 and BCL-XL were down-regulated, expressions of caspase 3 and sheared PAPP were up-regulated in NB4-R1 cells treated with 20 micromol/L of Curcumin. It is concluded that the Curcumin can inhibit the growth and induce the apoptosis of NB4-R1.

Isocitrate lyase from Mycobacterium tuberculosis promotes survival of Mycobacterium smegmatis within macrophage by suppressing cell apoptosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Isocitrate lyase (ICL) was previously demonstrated to play a pivotal role in the intracellular metabolism of Mycobacterium tuberculosis (MTB). Presently several lines of evidence suggest that ICL from MTB (MTB-ICL) may play some roles in the interaction between MTB and host macrophage. However, there has been no research on the interaction between MTB-ICL and host macrophage.</p><p><b>METHODS</b>MTB-icl and M. smegmatis (MS)-icl genes were amplified by polymerase chain reaction (PCR) and cloned into the E. coli-mycobacterium shuttle plasmid pUV15 to obtain recombinant shuttle plasmids pMTB-icl and pMS-icl. Following transformation into MS by electroporation, the expression of pMTB-icl and pMS-icl was verified by reverse transcriptase (RT)-PCR. The expression of recombinant plasmids derived from pUV15 when rMS was phagocytized by macrophage was also verified via fluorescence microscope. Ms 1 - 2c, rMS-pUV15, rMS-pMS-icl and rMS-pMTB-icl were used to infect RAW264.7 cells and the survival of intracellular MS was monitored by bacterial culture at 0, 24 and 48 hours after infection. The culture supernatants from macrophage infected by Ms 1 - 2c, rMS-pUV15, rMS-pMS-icl and rMS-pMTB-icl were collected and the interferon (IFN)-gamma and nitric oxide (NO) concentrations were measured by ELISA or by Griess assay, respectively. The apoptosis of macrophage was assayed by the in situ TUNEL technique.</p><p><b>RESULTS</b>RT-PCR showed that both pMTB-icl and pMS-icl could be expressed in MS. Fluorescence microscopic observation showed that recombinant plasmids derived from pUV15 (pUV15-IG) could also be expressed in MS when MS were phagocytized by macrophage. Bacterial culture data demonstrated that rMS-pMTB-icl exhibited significantly increased intracellular survival in the murine macrophage cell line RAW264.7 compared with Ms 1 - 2c, rMS-pUV15 and rMS-pMS-icl. This increased intracellular survival was not accompanied by the upregulation of IFN-gamma and NO in host macrophage. But a lower apoptosis rate of macrophages infected with rMS-pMTB-icl was observed when compared with macrophages infected with other strains of MS.</p><p><b>CONCLUSIONS</b>MTB-ICL could promote the intracellular survival of MS. Suppressing the apoptosis of host macrophage may be one of the important mechanisms involved in this increased intracellular survival.</p>