OBJECTIVEGas chromatography (GC) was used to investigate the cellular fatty acid (CFA) composition of 141 Acinetobacter baumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria.

METHODSWhole cell fatty acid methyl esters (FAMEs) were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System (MIS) analysis.

RESULTSAll A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18:1 ω9c, 16:0, Sum In Feature 3, 12:0, 17:1ω8c, 3-OH-12:0, 17:0, Sum In Feature 2, 2-OH-12:0, and 18:0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18:1 ω9c versus 16:0/18:1 ω9c and Sum In Feature 3/18:1 ω9c versus unknown 12.484/18:1 ω9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16:0 versus 17:0 and Sum In Feature 3/2-OH-12:0 versus 17:0 fatty acids.

CONCLUSIONThe ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. calcoaceticus.

Acinetobacter baumannii ; classification ; cytology ; metabolism ; Acinetobacter calcoaceticus ; classification ; cytology ; metabolism ; Biomarkers ; metabolism ; Fatty Acids ; metabolism ; Species Specificity

OBJECTIVE: To study the effect of low-dose dopamine adjuvant therapy on inflammatory factors and prognosis in preterm infants with necrotizing enterocolitis (NEC). METHODS: A total of 100 preterm infants with NEC from June 2017 to June 2019 were enrolled and divided into a dopamine treatment group and a conventional treatment group using a random number table, with 50 infants in each group. The infants in the conventional treatment group were given symptomatic treatment, and those in the dopamine treatment group were given low-dose dopamine adjuvant therapy in addition to the conventional treatment. ELISA was used to measure the levels of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-8 (IL-8). The two groups were compared in terms of time to relief of clinical symptoms, fasting time, treatment outcome, prognosis, and adverse reactions. RESULTS: Both groups had significant reductions in the levels of CRP, TNF-α, and IL-8 after treatment, and the dopamine treatment group had significantly lower levels of these markers than the conventional treatment group after treatment (P<0.05). Compared with the conventional treatment group, the dopamine treatment group had significantly shorter time to defecation improvement, time to relief of abdominal distension and diarrhea, and fasting time (P<0.05), a significantly higher response rate (P<0.05), and a significantly lower surgery rate (P<0.05). There were no significant differences in the mortality rate and incidence of adverse events between the two groups (P>0.05). CONCLUSIONS Low-dose dopamine adjuvant therapy can effectively improve the levels of inflammatory factors and clinical symptoms in preterm infants with NEC and has good safety, and therefore, it holds promise for clinical application.

Objective To compare the differences in the hypertension prevalence among children aged 7-12 in Guangzhou based on different references of hypertension. Methods A total of 7698 children aged 7-12 years old in Guangzhou were recruited by stratified cluster random sampling method. Demographic information such as gender and age was collected by questionnaire. Children’s height, weight, and blood pressure were objectively measured. There were five references for diagnosing children’s hypertension: Mi 2010, Mi 2017, Ma 2017, America 2004, and America 2017 reference. Results Based on the references above, the prevalence of hypertension for children aged 7-12 in Guangzhou reached a very high level. The prevalence of hypertension, high systolic blood pressure (SBP) and high diastolic blood pressure (DBP) based on Mi 2017 reference were all higher than those based on Mi 2010 reference, but both of them were distinctly higher than Ma 2017 reference. Compared with Mi 2010 reference, the agreement of diagnosis of high SBP and high DBP were both higher for Mi 2017 than those for Ma 2017. The agreement of high SBP was higher between Mi 2017 and America 2017 than that between Ma 2017 and America 2017 (Kappa: 0.846 vs. 0.727). Conclusion The prevalence of hypertension in children aged 7-12 in Guangzhou reachs a very high level. The prevalence of hypertension based on Mi 2017 reference is the highest and follows with America 2017 reference, and the agreement between them is excellent. Compared with Mi 2010 or America 2017 reference, the agreement for Ma 2017 is lower than that for Mi 2017 reference, respectively.

Objective To evaluate sedentary lifestyles after school in children aged 7 to 12 year-old living in Guangzhou, and to explore the association between sedentary behaviors after school with cardiometabolic risk factors. Methods Using the method of stratified cluster random sampling, this study recruited 7 to 12 year-old primary students (n=4 294) in Guangzhou. The physical examination and questionnaire were used to collect the sedentary lifestyles after school and cardiometabolic risk factors, analyzing the impact of different aedentary behavoir time after school on cardiometabolic risk factors. Results The average sedentary time after school per day were 194.3 min (boys: 200.3 min; girls: 187.3 min). Inter-quartile ranges of sedentary time after school per day were ≤130.0, 131.0-180.0, 181.0-240.0, and ≥241.0 min/d. Controlling for confounding factors, the odd ratios (OR) of central obesity, overweight/obesity, high TC status, high TG status and high LDL-C status in the highest compared to the lowest quartile of sedentary time after school per day were 1.39 (95%CI:1.08-1.80), 1.44 (95%CI:1.16-1.80), 1.26(95%CI:1.05-1.51), 1.63(95%CI:1.34-1.98), 1.28(95%CI:1.06-1.55), respectively. Conclusions Sedentary lifestyles have a positive relationship with childhood central obesity, overweight/obesity and dyslipidemia in primary school children. Therefore, it is essential to strengthen the intervention to the lifestyles of teenagers and reduce the sedentary behavior time of children and teenagers.

OBJECTIVETo study the expression of peptidyl-prolyl cis/trans isomerase (PPIase or Pin1) in malignant hematopoietic cells and its relation with cell cycle.

METHODSRealtime quantitative PCR with fluorescence probe hybridization was used to measure expression of Pin1 mRNA in malignant hematopoietic cell lines and normal mononuclear cells separated from bone marrow. HeLa cells were blocked with Thymidine and Nocodazole in different cell phases and then the expression of Pin1 mRNA and protein were detected by realtime-PCR and immunoblotting.

RESULTSThe expression of Pin1 in malignant hematopoietic cell lines was significantly higher than that in normal controls (0.339 +/-0.093 compared with 0.038 +/-0.005, P<0.01). Its expression in myeloid malignant hematopoietic cell lines was significantly higher than that in normal controls (0.388 +/-0.115 compared with 0.038 +/-0.005, P<0.01) and so was the malignant lymphocytic cell lines (0.226 +/-0.166 compared with 0.038 +/-0.005, P<0.01). The expression of Pin1 was closely correlated with cell cycle. It was the highest in G1 phase and the lowest in S phase (110.762 +/-16.737 compared with 4.080 +/-0.634, P<0.01).

CONCLUSIONPin1 is overexpressed in malignant hematopoietic cell lines and its expression is different during cell cycle that is highest in G1 phase and lowest in S phase.

Cell Cycle ; physiology ; G1 Phase ; Humans ; Leukemia, Lymphoid ; enzymology ; pathology ; Leukemia, Myeloid ; enzymology ; pathology ; Peptidylprolyl Isomerase ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; S Phase ; Tumor Cells, Cultured

OBJECTIVETo observe the distribution pattern of human telomere repeat binding factor 1(TRF1) in the telomerase-positive (HeLa) and telomerase-negative cells (WI38-2RA) and to investigate its expression level during the cell cycle.

METHODSThe full-length sequences of TRF1(TRF1FL) and its mutant with N and C terminus deletion (TRF1DeltaNC) were generated by PCR amplification, the resulting fragments were cloned into pEGFP-C2 mammalian expression vector. GFP-tagged proteins were verified by Western blotting with rabbit anti-TRF1 and mouse anti-GFP antibodies after cell transfection. Immunofluorescence staining were performed to detect the TRF1 localization in HeLa and WI38-2RA cells. Metaphase spreads from HeLa cells were also prepared to observe TRF1 localization in chromosomes. HeLa cells were arrested by thymidine and nocodazole at different cell stages. Cell cycles were analyzed by flow cytometry and TRF1 levels were evaluated by semi-quantitative Western blotting.

RESULTSTRF1FL and TRF1PNC fragments were sized about 1.3 kb and 0.95 kb. GFP-tagged TRF1FL and TRF1DeltaNC proteins were 80 kD and 60 kD, respectively. In both HeLa and WI38-2RA cells, TRF1FL had a speckled distribution in the nuclei,however, TRF1FL did not coincide with promyelocytic leukemia (PML) nuclear body in HeLa cells while it exclusively did in WI38-2RA cells. Moreover, TRF1FL was exactly localized at the termini of metaphase spreads in HeLa cells. In contrast, TRF1PNC was diffusely distributed throughout the nuclei. Analysis by semi-quantitative Western blotting indicated that TRF1 levels increased with cell cycle progression, which reached the zenith at the M phase and went down to the nadir at G1/S point. The TRF1 level at M phase was about 3.9 times than that at G1/S point(t=12.92iP<0.01).

CONCLUSIONTRF1 has a different localization in telomerase-positive and telomerase-negative cells, which suggests TRF1 might exert different functions in these cells. TRF1 level is regulated with cell cycle.

Cell Cycle ; HeLa Cells ; Humans ; Leukemia, Promyelocytic, Acute ; pathology ; Mutation ; Telomerase ; metabolism ; Telomere-Binding Proteins ; biosynthesis ; genetics ; metabolism ; Telomeric Repeat Binding Protein 1 ; biosynthesis ; genetics ; metabolism ; Tumor Cells, Cultured

Objective To investigate the effects of different dialysates on expression of protein kinase C-? (PKC?) and apoptosis of U937 cell line. Methods Different dialysates were added into culture fluid with U937 cell line at exponential phase of growth, and groups were divided: fluid A+fluid B group (dialysate A+dialysate B), fluid A+fluid B+rottlerin (PKC? specific inhibitor)group, fluid A+powder B group (dialysate A+powder B) and fluid A+powder B + rottlerin group. Besides, blank control group and normal control group were established. Cells were harvested 24 h and 48 h after treatment, morphological changes were observed by Hoechst33258 fluorescence staining, cell apoptosis was measured by Annexin-V-FITC/PI double staining, and expression of PKC? mRNA and protein was detected by RT-PCR and Western blotting, respectively. Results Cell apoptosis significantly increased in fluid A+powder B group, with typical morphology of apoptosis. After treatment for 24 h and 48 h, cell apoptosis rates in fluid A+powder B group were significantly higher than those at corresponding time points in blank control group, normal control group and fluid A+powder B+rottlerin group (P0.05). Conclusion Fluid A+powder B can significantly increase apoptosis of U937 cell line, the mechanism of which may be associated with the up-regulation of expression of PKC?. Compared with fluid A+powder B, fluid A+fluid B is superior in reducing apoptosis of peripheral blood monouclear cells.

OBJECTIVETo investigate the functional relations between the putative proteins YpCD1.08, YpCD1.09, YpCD1.16 encoded in pCD1 plasmid of Yersinia pestis and its type III secretion system (T3SS).

METHODSMutants of YpCD1.08, YpCD1.09, YpCD1.16 were constructed using λ-Red recombinant system. The growth curves of the mutant strains cultivated in TMH medium with or without calcium at 26 °C and 37 °C were determined to analyze the low calcium response phenotype. The transcription levels of ΔYpCD1.08, ΔYpCD1.09, ΔYpCD1.16 in Yersinia pestis and the dependence to temperature were determined using real time RT-PCR after cultivation at 26 °C and 37 °C and extraction of RNA. A β-lactamases reporter system was adopted to study the influence of these genes on the translocation of effector YopE of T3SS.

RESULTSWhen grown in TMH medium without calcium at 26 °C and 37 °C, the growth curve of the YpCD1.08, YpCD1.09, YpCD1.16 mutants were similar to that of the wild-type strain, indicating that the low calcium response of all the mutants were normal. The ratios of YpCD1.08, YpCD1.09, YpCD1.16 gene transcriptional level at 37 °C and 26 °C were 2.3 ± 0.3, 2.3 ± 0.5 and 3.2 ± 0.7, respectively, indicating that these genes were transcribed in Yersinia pestis and their transcription regulations showed a temperature-dependence that was consistent with the well established temperature-dependent expression of Yersinia T3SS genes. The β-lactamases reporter assays demonstrated that ΔYpCD1.08 could translocate much higher level of YopE into HeLa cells, since that the light intensity ratio of 477/520 nm at 140 min was 2.5, whereas it was 1.8 for the wild-type strain, and the values in ΔYpCD1.09 and ΔYpCD1.16 were similar to the wild-type strain.

CONCLUSIONYpCD1.08, YpCD1.09, YpCD1.16 gene are likely to be the new members of T3SS, and the putative protein YpCD1.08 could play some roles in YopE secretion and translocation.

Bacterial Outer Membrane Proteins ; secretion ; Bacterial Secretion Systems ; genetics ; Genes, Bacterial ; Plasmids ; Protein Interaction Mapping ; Yersinia pestis ; genetics ; metabolism ; pathogenicity

OBJECTIVETo study the expression of human telomere repeat binding factor 1 (TRF1) to investigate the correlation of telomerase activity with acute leukemia.

METHODSLeukemic cells were collected from 30 cases of acute leukemia. Realtime quantitative PCR with fluorescence probe hybridization was used to measure expression of TRF1 and hTERT mRNA in leukemic cells.

RESULTSTRF1 mRNA expression was 0.0126 (0.0127-0.0546) in acute non-lymphocytic leukemia (ANLL), which was lower than that in normal mononuclear cells [0.0457 (0.00839-0.262), P<0.001], but its expression in acute lymphoblastic leukemia (ALL) cells [0.0745 (1.92 x 10(-6)-0.193)] had no significant difference compared with that in normal mononuclear cells. TRF1 expression in ANLL cells was significantly lower than that in ALL cells (P=0.001). The expressions of TRF1 mRNA in AL cells and normal mononuclear cells had no significant correlation with expression of hTERT mRNA (r=-0.173, P=0.207).

CONCLUSIONThe expression of TRF1 is lower in ANLL cells, which indicates TRF1 may have some effect on telomerase activity by regulating telomere length in ANLL cells.

Adolescent ; Adult ; Aged ; Female ; Humans ; Leukemia, Myeloid, Acute ; enzymology ; metabolism ; Male ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; enzymology ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Telomerase ; metabolism ; Telomeric Repeat Binding Protein 1 ; biosynthesis ; genetics

OBJECTIVETo investigate the telomerase activity in mesenchymal stem cells (hMSCs) from human bone marrow after their in vitro committed differentiation into adipocytes and cryopreservation.

METHODShMSCs were isolated from human bone marrow. The isolated hMSCs were induced to differentiate into adipocytes in vitro or cryopreserved. TRAP assay (telomerase repeat amplification protocol assay) was employed to detect telomerase activity in those hMSCs.

RESULTSTelomerase activity (RTA) in hMSCs (n=19) was (1.46 +/-0.67)%, while that in hMSCs-derived adipocytes (n=3) was (11.80 +/-2.52)% (P<0.001). RTA of hMSCs-passage 1.3 (n=10) was (1.46+/-0.83)%, and that of hMSCs-passage 4-7(n=9) was (1.46 +/-0.47)% (P=0.99). Cryopreservation did not affect the telomerase activity in hMSCs, RTA of fresh hMSCs (n=13) was (1.41 +/-0.44)%, RTA of frozen hMSCs (n=6) was (1.57 +/-1.07)% (P=0.64).

CONCLUSIONhMSCs are telomerase-negative, but telomerase activity in hMSCs-derived adipocytes is upregulated.

Adipocytes ; cytology ; enzymology ; Bone Marrow Cells ; cytology ; enzymology ; Cell Differentiation ; Cells, Cultured ; Cryopreservation ; Humans ; Mesenchymal Stromal Cells ; cytology ; enzymology ; Telomerase ; metabolism