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.

The outer membrane composed predominantly of lipopolysaccharide (LPS) is an essential biological barrier for most Gram-negative (G^-) bacteria. Lipopolysaccharide transport protein (Lpt) complex LptDE is responsible for the critical final stage of LPS transport and outer membrane assembly. The structure and function of LptDE are highly conserved in most G^- bacteria but absent in mammalian cells, and thus LptDE complex is regarded as an attractive antibacterial target. In recent 10 years, the deciphering of the three-dimensional structure of LptDE protein facilities the drug discovery based on such "non-enzyme" proteins. Murepavadin, a peptidomimetic compound, was reported to be the first compound able to target LptD, enlightening a new class of antibacterial molecules with novel mechanisms of action. This article is devoted to summarize the molecular characteristics, structure-function of LptDE protein complex and review the development of murepavadin and related peptidomimetic compounds, in order to provide references for relevant researches.

Neoadjuvant chemoradiotherapy or chemotherapy combined with surgery for locally advanced esophageal cancer has become the standard treatment, and despite the survival benefit, most patients still experience postoperative recurrence and distant metastasis. Immune checkpoint inhibitors play an anti-tumor role by activating T cells, and immunotherapy has become one of the important strategies for first-line and second-line treatment of advanced esophageal cancer with the continuous evolution of immunotherapy models. Regarding neoadjuvant immunotherapy for esophageal cancer, a large number of studies are being carried out and explored, which are expected to inject new vitality into neoadjuvant therapy for esophageal cancer. This article reviews the current clinical studies on neoadjuvant immunotherapy for esophageal cancer.

Objective:To analyze the level and clinical significance of IL-18 and IL-18-binding protein (BP) in the bone marrow of patients with myelodysplastic syndrome (MDS) .Methods:A total of 43 newly diagnosed patients with MDS who were admitted to the Department of Hematology, Tianjin Medical University General Hospital, from July 2020 to February 2021 were randomly selected. The control group consisted of 14 patients with acute myeloid leukemia (AML) and 25 patients with iron-deficiency anemia (IDA). The levels of IL-18 and IL-18 BP in the bone marrow supernatant were measured, and their correlations with MDS severity, as well as the functionality of CD8 + T cells and natural killer cells, was analyzed. Results:The levels of IL-18, IL-18 BP, and free IL-18 (fIL-18) in the bone marrow supernatant of patients with MDS were higher than in the IDA group. The level of fIL-18 was linearly and negatively correlated with the MDS-International Prognostic Scoring System (IPSS) score. IL-18 receptor (IL-18Rα) expression on CD8 + T cells in the MDS group was lower than in the IDA group, and the levels of fIL-18 and IL-18Rα were positively correlated with CD8 + T-cell function in the MDS group. Conclusion:IL-18 BP antagonizes IL-18, leading to a decrease in fIL-18 in the bone marrow microenvironment of patients with MDS, affecting CD8 + T-cell function, which is closely related to MDS severity; therefore, it may become a new target for MDS treatment.

Objective To compare the differences in dosimetric parameters between gradient optimization(GO)method and dynamic multi leaf collimator automatic optimization(dMLC-AO)method in craniospinal irradiation(CSI)to provide references for enhancing the feasibility of CSI planning of Monaco treatment planning system.Methods Fifteen patients undergoing CSI at some hospital were retrospectively selected,and a GO plan(enrolled into a GO group)and a dMLC-AO plan(enrolled into a dMLC-AO group)were designed for volumetric modulated arc therapy for each patient by the Monaco treatment planning system.The two groups were compared in terms of the dosimetric parameters of the planning target volume,dose transition zone and organ at risk.SPSS 24.0 statistical software was used for data analysis.Results The dMLC-AO group behaved slightly better than the GO group in D98％ and homogeneity index,with the differences being significant(P＜0.05),while the two groups were not different statistically in D2％,D50％and conformity index(P＞0.05).There were no significant differences between the two groups in radiation doses to the organs at risk except intestinal Dmean(P＞0.05).The GO group gained advantages over the dMLC-AO group in dose distribution conformity at the drop zone,and the target volume length covered by the 36 Gy isodose line for the intermdediate-section plan of the GO group was significantly longer than that of the dMLC-AO group.Conclusion GO method behaves better than dMLC-AO method in controlling effectively the dose drop at the dose transition zone of CSI plan.[Chinese Medical Equipment Journal,2024,45(9):62-66]

Aim To investigate the protective effect of carnosine on BV2 cell damage induced by oxygen-glu-cose deprivation/reperfusion(OGD/R)and its role in mediating pyrodeath through the ROS/NLRP3/GSDMD pathway.Methods BV2 cells were randomly divided into the control group(Con),model group(OGD/R),carnosine group(OGD/R+CAR),inhibitor group(OGD/R+MCC950),and carnosine+inhibitor group(OGD/R+CAR+MCC950).The cell survival rate was detected by MTT assay.The release rate of lactate dehydrogenase(LDH)in cell supernatant was detected by microenzyme labeling method.Cell damage was as-sessed using Hoechst 33342/SYTOX Green staining.ROS levels in cells were detected by DCFH-DA.The nucleation level of NF-κB p65 was observed by immu-nofluorescence.The protein expression levels of NLRP3,ASC,cleaved caspase-1,and GSDMD-N were detected by Western blot.The levels of IL-1 β and IL-18 in the supernatant were detected by ELISA.Results Com-pared with Con group,the survival rate of cells in the OGD/R group was significantly reduced,LDH release was significantly raised,cell morphology was damaged,and the positive rate of SYTOX Green was significantly elevated with ROS level in cells.The fluorescence in-tensity of NF-κB p65 in the nucleus increased,and the protein expression levels of NLRP3,ASC,cleaved caspase-1,GSDMD-N increased significantly,and the levels of IL-1 β and IL-18 in the cell superserum in-creased significantly.Compared with the OGD/R group,the survival rate of cells in other groups in-creased significantly,the LDH release rate significantly decreased,and the cell damage was improved to a cer-tain extent.The positive rate of SYTOX Green and ROS production in cells significantly decreased,and the fluorescence intensity of NF-κB p65 in nucleus markedly decreased.The expression levels of related proteins and the levels of IL-1 β and IL-18 in cell super-natant significantly decreased.Conclusion Carnosine can protect BV2 cells from OGD/R-induced damage by inhibiting oxidative stress and NF-κB activation,then inhibiting NLRP3/GSDMD signaling pathway.

Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder characterized by chronic hyperglycemia, hyperlipidemia, and peripheral insulin resistance. Endoplasmic reticulum stress (ERS), a response to cellular stress, is activated across various tissues during the progression of T2DM, leading to disruptions in protein synthesis. Notably, epithelial and endocrine cells with hormone-secreting functions are particularly vulnerable to functional impairments induced by ERS. The gut-pancreas axis is essential for regulating metabolism and the progression of T2DM. Intestinal epithelial L cells, integral to the intestinal barrier, can secrete the glucagon-like peptide-1 (GLP-1). This hormone promotes insulin secretion from pancreatic β-cells and plays a critical role in glucose metabolism. Importantly, ERS plays a critical role in regulating glucolipid-induced dysfunction of gut-pancreas axis. For instance, ERS is involved in regulating the intestinal barrier and the secretion of GLP-1 as well as insulin. Therefore, ERS can be a potential target for T2DM treatment. In this paper, we review the regulatory roles of ERS in the gut-pancreas axis during the development of T2DM, and summarize the therapeutic drugs and strategies targeting ERS for T2DM treatment.

To analyze the correlation between the duration of hyperbaric oxygen (HBO) therapy and oral medication clonazepam reduction in patients with paroxysmal sympathetic hyperactivity (PSH).

Mitochondrial diabetes mellitus (MDM) is a genetically heterogeneous disorder caused by mitochondrial DNA (mtDNA) or nuclear DNA mutations, characterized by multi-system involvement and diverse clinical phenotypes. We report a pediatric case presenting with growth retardation followed by subsequent development of diabetes mellitus. Systematic evaluation revealed concurrent bilateral sensorineural hearing loss, bilateral basal ganglia calcification, and electroencephalographic abnormalities. A post-exercise lactate test demonstrated significant elevation of serum lactate levels immediately after physical exertion. Genetic analysis identified a large-scale mitochondrial DNA deletion spanning from m.8649 to m.16084. This case report is complemented by a literature review focusing on the pathogenesis, genetic characteristics, and therapeutic approaches of mitochondrial diabetes, with particular emphasis on mitochondrial disorders exhibiting large-scale mtDNA deletions alongside diabetic manifestations. Our comprehensive analysis aims to enhance clinical understanding and inform diagnostic strategies for this complex disease entity.

Accumulating studies have demonstrated that non-coding RNAs (ncRNAs), functioning as important regulators of transcription and translation, are involved in the establishment and maintenance of pregnancy, especially the maternal immune adaptation process. The endometrial stromal cells (ESCs), trophoblast cells, and decidua immune cells that reside at the maternal-fetal interface are thought to play significant roles in normal pregnancy and pregnancy-associated diseases. Here, we reviewed the up-to-date evidence on how microRNA, long non-coding RNA, and circular RNA regulate ESCs, trophoblast cells, and immune cells and discussed the potential applications of these ncRNAs as diagnostic and therapeutic markers in pregnancy complications.
Pregnancy ; Female ; Humans ; MicroRNAs/genetics* ; RNA, Long Noncoding/genetics* ; RNA, Circular/genetics* ; Trophoblasts ; Pregnancy Complications/genetics*