[Characteristics of drug resistance and biofilm formation in carbapenem-resistant Acinetobacter baumannii in hospitalized children]. / 住院患儿耐碳青霉烯类鲍曼不动杆菌的耐药及生物膜特征分析.

OBJECTIVES: To study the distribution, drug resistance, and biofilm characteristics of carbapenem-resistant Acinetobacter baumannii (CRAB) isolated from hospitalized children, providing a reference for the prevention and treatment of CRAB infections in hospitalized children. METHODS: Forty-eight CRAB strains isolated from January 2019 to December 2022 were classified into epidemic and sporadic strains using repetitive extragenic palindromic sequence-based polymerase chain reaction. The drug resistance, biofilm phenotypes, and gene carriage of these two types of strains were compared. RESULTS: Both the 22 epidemic strains and the 26 sporadic strains were producers of Class D carbapenemases or extended-spectrum ß-lactamases with downregulated outer membrane porins, harboring the VIM, OXA-23, and OXA-51 genes. The biofilm formation capability of the sporadic strains was stronger than that of the epidemic strains (P<0.05). Genes related to biofilm formation, including Bap, bfs, OmpA, CsuE, and intI1, were detected in both epidemic and sporadic strains, with a higher detection rate of the intI1 gene in epidemic strains (P<0.05). CONCLUSIONS: CRAB strains are colonized in the hospital, with sporadic strains having a stronger ability to form biofilms, suggesting the potential for forming new clonal transmissions in the hospital. Continuous monitoring of the epidemic trends of CRAB and early warning of the distribution of epidemic strains are necessary to reduce the risk of CRAB infections in hospitalized children.

Circulating serum trefoil factor 3 (TFF3) is dramatically increased in chronic kidney disease.

OBJECTIVES: Trefoil factor 3 (TFF3) is a small peptide that plays an important role in mucosal protection, cell proliferation, and cell migration. The aberrant expression of TFF3 is correlated with gastrointestinal inflammation, solid tumors, and other clinical diseases. The objective of this study was to identify the distribution characteristics of serum TFF3 in common clinical diseases. MATERIALS AND METHODS: A large prospective randomized study of 1,072 Chinese patients was performed using an enzyme-linked immunosorbent assay (ELISA) to examine the serum TFF3 concentrations in patients with different diseases. A matched case-control study was conducted on patients with chronic kidney disease (CKD) stages 1-5. Immunohistochemistry (IHC) was performed using renal tissues to determine the relationship between the severity of CKD and the serum and urine concentrations of TFF3 peptides. RESULTS: The mean serum concentrations of TFF3 in patients with CKD, metastatic and secondary carcinoma (MC) and acute gastroenteritis (AG) (200.9 ng/ml, 95.7 ng/ml and 71.7 ng/ml, respectively) were significantly higher than those in patients with other common clinical diseases. A positive correlation tendency was observed between the serum TFF3 concentrations and the severity of CKD. The mean serum TFF3 values for CKD stages 1-5 were 23.6 ng/ml, 29.9 ng/ml, 54.9 ng/ml, 85.0 ng/ml and 176.6 ng/ml, respectively. The same trend was observed in the urine TFF3 concentrations and the CKD stages. The creatinine(Cr)-corrected concentrations of TFF3 in urine were 367.1 ng/mg·Cr, 910.6 ng/mg·Cr, 1,149.0 ng/mg·Cr, 1,610.0 ng/mg·Cr and 3,475.0 ng/mg·Cr for CKD stages 1-5, respectively. IHC revealed that TFF3 expression was concentrated in tubular epithelial cells. CONCLUSIONS: The influence of kidney injuries must be fully considered when performing clinical TFF3 research. Further studies on TFF3 in CKD will contribute to our understanding of its pathological roles and mechanisms in other diseases.

[Detection and comparison of physiological indexes in the wild and laboratory tree shrew].

To provide fundamental basis for the tree shrew models of human diseases, we examined and compared the physiological and biochemical indexes between wild and laboratory tree shrews. Blood samples were taken from 54 wild tree shrews that were housed in laboratory for 1-2 months, and from 54 first-generation of the laboratory tree shrews; each group had nearly equal male and female composition. Some of the first reported physiological and biochemical indexes were showed no significant differences between genders, and these indexes in laboratory tree shrews were as follows [medium (inter-quartile range) ]: CK 1449 (956) U/L, CTNI 5.94 (7.23) ug/L, TBA15.6 (19.7) µmol/L, FRUC 393.5 (80.8) µmol/L and LDL-C0.36 (0.32); and in the wild tree shrews, 986 (564) U/L, 4.01 (4.10) µg/L, 20.0 (20.6) µmol/L, 379.0 (104.0) µmol/L and 0.46 (0.23) mmol/L, respectively. In the laboratory tree shrews, the variations of physiological and biochemical indexes were smaller, but the mean values of some indicators related to liver and heart functions became higher. These data would be valuable for the development of tree shrew models of human diseases.

[Trefoil factor: from laboratory to clinic].

Trefoil factor (TFF) family is a group of peptides with one or several trefoil factor domains in their structure, which are highly conserved in evolution, and are characterized by heat and enzymatic digestion resistance. The mammalian TFFs have three members (TFF1-3), and the gastrointestinal tract and the airway system are major organs of their expression and secretion. At certain physiological conditions, with a tissue-specific distribution, TFF plays an important role in mucosal protection and wound healing. But in the malignant tissues, TFF is widely expressed, correlated strongly with the genesis, metastasis and invasion of tumor cells. These phenomena indicated that TFF may be a possible common mediator of oncogenic responses to different stimuli. The biological functions of TFF involve complex regulatory processes. Single chain TFF may activate cell membrane receptors and induce specific signaling transduction. On the other hand, TFF can form a complex with other proteins to exert its biological effects. In clinical medicine, TFF is primarily applied as drugs in the mucosal protection, in the prevention and the treatment of mucosal damage-related diseases and as pathological biomarkers of tumors. At present the first hand actions and the molecular mechanisms related to TFFs are still the major challenges in TFF research. Furthermore, the discovery of the naturally occurring complex of TFF and crystallins is highly valuable to the understanding of the biological functions and action mechanisms of TFF.