Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

BACKGROUND: Hematopoietic stem cells (HSCs) have the ability to differentiate into all subsets of blood cells and self-renew. Large tumor suppressor 1 (LATS1) and large tumor suppressor 2 (LATS2) kinases are essential for cell cycle regulation, organism fitness, genome integrity, and cancer prevention. Here, we investigated whether Lats1 and Lats2 are critical for the maintenance of the self-renewal and quiescence capacities of HSCs in mice. METHODS: Quantitative reverse transcription-polymerase chain reaction was used to determine the expression levels of Lats1 and Lats2 in subsets of progenitor cells and mature bone marrow cells. A clustered regularly interspaced short palindromic repeats system was used to generate Lats1 or Lats2 knockout mice. Complete blood cell counts were used to compare the absolute number of white blood cells, lymphocytes, monocytes, neutrophils, and platelets between Lats1 or Lats2 heterozygotes and littermates. Flow cytometry was used to assess the size of hematopoietic progenitor cells (HPCs) and HSC pools in Lats1 or Lats2 heterozygotes and littermates. The comparison between the two groups was analyzed using Student's t test. RESULTS: Lats1 and Lats2 were widely expressed in hematopoietic cells with higher expression levels in primitive hematopoietic cells than in mature cells. Lats1 or Lats2 knockout mice were generated, with the homozygotes showing embryonic lethality. The size of the HPC and HSC pools in Lats1 (HPC: wild-type [WT] vs. heterozygote, 220,426.77 ± 54,384.796 vs. 221,149.4 ± 42,688.29, P = 0.988; HSC: WT vs. heterozygote, 2498.932 ± 347.856 vs. 3249.763 ± 370.412, P = 0.105) or Lats2 (HPC: WT vs. heterozygote, 425,540.52 ± 99,721.86 vs. 467,127.8 ± 89,574.48, P = 0.527; HSC: WT vs. heterozygote, 4760.545 ± 1518.01 vs. 5327.437 ± 873.297, P = 0.502) heterozygotes were not impaired. Moreover, the depletion of Lats1 or Lats2 did not affect the overall survival of the heterozygotes (Lats1: P = 0.654; Lats2: P = 0.152). CONCLUSION These results indicate that a single allele of Lats1 or Lats2 may be sufficient for normal hematopoiesis.

BACKGROUND: Zinc finger and BTB domain-containing protein 46 (Zbtb46) is a transcription factor identified in classical dendritic cells, and maintains dendritic cell quiescence in a steady state. Zbtb46 has been reported to be a negative indicator of acute myeloid leukemia (AML). We found that Zbtb46 was expressed at a relatively higher level in hematopoietic stem and progenitor cells (HSPCs) compared to mature cells, and higher in AML cells compared to normal bone marrow (BM) cells. However, the role of Zbtb46 in HSPCs and AML cells remains unclear. Therefore, we sought to elucidate the effect of Zbtb46 in normal hematopoiesis and AML cells. METHODS: We generated Zbtb46 and Zbtb46Mx1-Cre mice. The deletion of Zbtb46 in Zbtb46Mx1-Cre mice was induced by intraperitoneal injection of double-stranded poly (I). poly (C) (poly(I:C)), and referred as Zbtb46 cKO. After confirming the deletion of Zbtb46, the frequency and numbers of HSPCs and mature blood cells were analyzed by flow cytometry. Serial intraperitoneal injection of 5-fluorouracil was administrated to determine the repopulation ability of HSCs from Zbtb46 and Zbtb46 cKO mice. The correlation between Zbtb46 expression and prognosis was analyzed using the data from the Cancer Genome Atlas. To investigate the role of Zbtb46 in AML cells, we knocked down the expression of Zbtb46 in THP-1 cells using lentiviral vectors expressing small hairpin RNAs targeting Zbtb46. Cell proliferation rate was determined by cell count assay. Cell apoptosis and bromodeoxyuridine incorporation were determined by flow cytometry. RESULTS: The percentages and absolute numbers of HSPCs and mature blood cells were comparable in Zbtb46 cKO mice and its Zbtb46 littermates (Zbtb46vs. Zbtb46 cKO, HPC: 801,310 ± 84,282 vs. 907,202 ± 97,403, t = 0.82, P = 0.46; LSK: 86,895 ± 7802 vs. 102,210 ± 5025, t = 1.65, P = 0.17; HSC: 19,753 ± 3116 vs. 17,608 ± 3508, t = 0.46, P = 0.67). The repopulation ability of HSCs from Zbtb46Mx1-Cre mice was similar to those from Zbtb46 control (P = 0.26). Zbtb46 had elevated expression in AML cells compared to total BM cells from normal control. Knockdown of Zbtb46 in THP-1 cells led to a significant increase in cell apoptosis and reduced cell growth and proliferation. CONCLUSION Collectively, our data indicate that Zbtb46 is essential for survival and proliferation of AML cells, but dispensable for normal hematopoiesis.

Objective To evaluate the demand for midwives in Yunnan province utilizing Birthrate Plus for planning and development of such workforce. Methods A convenient sample method was used to investigate 8435 maternal cases at 9 hospitals in Yunnan province in four months from 9 - 12 in 2017, and Birthrate Plus was used to calculate the demand for midwifery at each hospital. We also analyzed the two core elements of Birthrate Plus- maternal category allocation and midwife hours of each hospital. Results Maternal cases fall into five categories and maternal category allocation in hospitals is roughly the same;Maternal in higher category tended to need longer midwife hours; the average birthrate of 9 hospitals was (194. 22 ± 44. 84) case/ ( year·midwife). The number of midwives in two tertiary hospitals is obviously insufficient. Midwives at 7 secondary hospitals are more than predicted. Conclusions Midwives in Yunnan are generally faced with a large workload, especially at secondary hospitals, and midwives need to bear numerous non-midwifery workload beyond Birthrate Plus. Therefore, the Birthrate Plus can reflect the midwifery workload scientifically and reasonably in the current situation of midwifery work. But the predication for midwifery workforce requires a study of the ratio of midwifery work in the entire clinical work of the hospital.

Objective: To understand the current situation of maternal health care in this area, and to provide basis for further improving the quality of maternal and child health care service in this area and in the western region of China. Methods: The clinical data of 8 539 pregnant women from 10 hospitals in Yunnan Province was collected, including the general situation, the situation of medication and intervention during delivery, the mode of delivery and the outcome of delivery. Results: Age (χ²=149.878, P<0.01), number of pregnancies (χ²=12.251, P<0.01), times of delivery (χ²=49.141, P<0.01), number of fetuses (χ²=18.580, P<0.01) and history of pregnancy (χ²=146.688, P<0.01)all affected the incidence of complications during parturition. And whether there are maternal complications will affect the situation of medication (χ²=131.959, P<0.01), induced labor (χ²=13.129, P<0.01) and the length of midwifery service in the delivery room (Z=-14.328, P<0.01). Conclusion Paying attention to the pregnant women with pregnancy complications/complications could help to reduce the maternal mortality rate, and provide the high-level health care for mothers and children in Yunnan Province and even in the western region of China.

Objective To study the relationship among rs505802 in SLC22A12,rs6855911,rs737267,rs12498742, rs7442295, rs734553, rs16890979 in SLC2A9 genetic polymorphisms and hypouricemia in Ningxia.Methods 6 056 subjects were collected by multistage,stratified random cluster sampling method in October and November in 2011 in Ningxia Hui autonomous region, 98 subjects with hypouricemia were selected.According to gender and age,84 controls were selected.Physical examination and laboratory biochemical index test were conducted for the study population.T test was used to compare general clinical data and biochemical indexs between two groups. SNPs were detected by Sequenom Mass ARRAY technology.By x2test,we compared the frequencies of the geno-type and allele in each group.Samples representativeness was confirmed through the Hardy-Weinberg inspection. Results The levels of TC, LDLC, and Cr in the patients were lower than those in the control group(P<0.05). There were significant differences in the distribution of A,G allele frequencies of SLC2A9 gene rs7442295 between two groups.The risk of hypouricemia in patients with A/A genotype was lower than that of A/G genotype(Pc<0.05),indicating that A>G mutation was associated with hypouricemia.Conclusions Polymorphisms of SLC2A9 gene rs7442295 are significantly correlated with hyporuricemia in Ningxia.

In order to investigate the genetic difference on medicinal components of Scutellaria baicalensis from different provenances on the genetic difference, the S. baicalensis provenance tests were arranged by randomized block design.Excavating the crude drugs that have been growing for three years, with the same drying process, the content of baicalin, baicalein, wogonoside, wogonin and laminarin A in S. baicalensis were detected by HPLC, and then the data were analyzed. The results indicated that the content of baicalin in different provenances of S. baicalensis was significantly different (<0.05), while the variation of baicalein reached extremely significant level (<0.01). Cluster analysis showed that if the distance was divided by 5.0, the provenances in Chengde, Hebei province were divided into two independent populations, while the other two populations had large geographic spans. The results show that the significant geographical variations exist in the content of medicinal components in S. baicalensis. The study laid a theoretical foundation of provenance selection of S. baicalensis.

To explore the protective effect of naringin(Nar) on the injury of myocardium tissues induced by streptozotocin(STZ) in diabetic rats and the relationship with oxidative stress and endoplasmic reticulum stress(ERS)， the male SD rats were intraperitoneally injected with streptozotocin(STZ， 60 mg·kg⁻¹) to establish the diabetic rat model and then randomly divided into the type 1 diabetic rat group(T1DR)， the low-dose Nar group(Nar25)， the middle-dose Nar group(Nar50) and the high-dose Nar group(Nar100). The normal rats were designed as control group(Con). Nar25， Nar50， Nar100 groups were orally administered with Nar at the doses of 25.0， 50.0， 100.0 mg·kg⁻¹ per day， respectively， while the normal group and the T1DR group were orally administered with saline. At the 8th week after treatment， fasting plasma glucose and heart mass index were measured. The pathological changes in myocardial tissues were observed by microscope. The cardiac malondialdehyde(MDA) level and superoxide dismutase(SOD) activities were measured. The gene and protein expressions of glucose-regulated protein 78(GRP78)， C/EBP homologous protein(CHOP)， cysteinyl aspartate-specific proteinase 12(caspase 12) were detected by qRT-PCR and Western blot. According to the results， compared with control group， the myocardial structure was damaged， the content of MDA was increased， while the activities of SOD were decreased(<0.05) in T1DR group. GRP78， CHOP and caspase 12 mRNA and protein expressions were increased significantly in T1DR group(<0.05， <0.01). Compared with T1DR group， myocardial structure damage was alleviated in Nar treatment group. The content of MDA was decreased， while the activities of SOD were increased significantly. The mRNA and protein expressions of GRP78， CHOP and caspase 12 were increased， especially in middle and high-dose groups(<0.05， <0.01). After treatment with Nar for 8 weeks， myocardial structure damage was obviously alleviated in Nar treatment groups. The content of MDA was decreased， while the activities of SOD were increased significantly in myocardial tissues. The mRNA and protein expressions of GRP78， CHOP and caspase 12 were increased， especially in middle and high-dose groups(<0.05， <0.01). The findings suggest that Nar may protect myocardium in diabetic rats by reducing mitochondrial oxidative stress injuries and inhibiting the ERS-mediated cell apoptosis pathway.
Animals ; Apoptosis ; Cardiotonic Agents ; pharmacology ; Caspase 12 ; metabolism ; Diabetes Mellitus, Experimental ; Diabetic Cardiomyopathies ; drug therapy ; Endoplasmic Reticulum Stress ; drug effects ; Flavanones ; pharmacology ; Heat-Shock Proteins ; metabolism ; Male ; Malondialdehyde ; metabolism ; Oxidative Stress ; drug effects ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism ; Transcription Factor CHOP ; metabolism

Objective To evaluate the changes in epithelial thickness profile and its relationship with diopter following small incision lenticule extraction (SMILE) for moderate and high myopia.Methods Together 46 myopia or myopic astigmatism (92 eyes) who underwent SMILE were included under the informed consent from January 2016 to March 2017 and were decided into 2 groups according to the diopter:moderate myopia group (58 eyes)and high myopia group (34 eyes).Epithelial thickness profile was measured using spectral-domain optical coherence tomography at different corneal zones (0-2 mm,＞ 2-5 mm and ＞ 5-6 mm cornea) preoperatively before surgery and 1 month and 6 months after surgery for observing the changes in epithelial thickness and its correction with diopter.Results The mean epithelial thickness in the central zone was (55.68 ± 3.61) μm before surgery,and,6 months after surgery,it was thickened by (3.85-±3.99),(3.46 ±3.29) and (2.85 ±3.18) μm in the 0-2 mm,＞2-5 mum and ＞5-6 mm cornea respectively,and the difference was statistically significant among the three zones (P ＜ 0.01).After surgery for 6 months,the epithelial thickness in the high myopia group was thickened more obviously compared with the moderate myopia group (t =1.440,P =-0.047).And no correlation was found between changes in the epithelial thickness at 0-2 mm cornea and diopter after surgery(moderate myopia group:r =0.219,P=0.633;high myopia group:r =0.197,P =0.585).Conclusion Significant epithelial thickening was observed after SMILE,presenting the thickened epithelium.The higher the diopter was,the more thickened the epithelium was.The epithelial changes does not appear to affect the diopter after SMILE.

Objective To evaluate the reliability of HARSHAW-3500 thermoluminescence dosimetry system by testing its performances.Methods HARSHAW-3500 thermoluminescence dosimetry system had its performances tested and evaluated according to Verification regulation of thermoluminescence dosimetry systems used in persontal and environmental monitoring forXandgammaradiation(JJG 593-2006),Testingcriteriaofpersonneldosimetryperformanceforexternalexposure (GBZ 207-2016),Specifications for individual monitoring of occupational external exposure (GBZ 128-2016) and Thermoluminescence dosimetry systems for personal and environmental monitoring (GB/T 10264-2014),such as batch homogeneity,repeatability,linearity,incidence angle response,stability,energy response and scale factor,quantity inspection,residual dose,detection limit and etc.Results Testing results of various performance indicators proved to be within the limits according to national and industrial standards.Conclusion HARSHAW-3500 thermoluminescence dosimetry system conforms to the requirements for radiation dose measurement.It is beneficial to the improvement of quality and performance of thermoluminescence dosimetry by performances analysis and evaluation.