Objective To explore the biliary tract microbiota changes before and after drainage treatment in patients with malignant biliary obstruction(MBO),and to study the effects of biliary obstruction and drainage intervention on the bile microbiota from a microecological point of view.Methods From January 2020 to December 2022,DSA-guided percutaneous transhepatic catheter drainage(PTCD)was carried out in 32 patients with MBO.A 22G drainage needle was inserted into the bile duct,and about 15-20mL of bile was extracted after it was confirmed that the needle was located within the intrahepatic bile duct,then,an external drainage tube,or an internal drainage tube together with an external drainage tube,was implanted into the bile duct along the guide wire.Seven days after PTCD,bile was extracted through a drainage tube.Bile sampling for germiculture and gene sequencing was conducted twice.The general data of patients,including whether acute cholangitis occurred and its severity,whether antibiotics was used for treatment,etc.,were collected.Results Of the 32 patients,cholangiocarcinoma was seen in 15,pancreatic cancer in 10,hepatocellular carcinoma in 3,and hilar lymph node metastasis from gastrointestinal malignant tumor in 4.Before PTCD,in the bile microbiota the burkholderia,acinetobacter,pseudomonas and staphylococcus were the bacteria with a high relative abundance,and the diversity and evenness of other microbial species seen in the normal biliary tract were reduced.Conclusion There is a stable microbiota within the normal biliary system,and in malignant obstructive biliary tract the microbiota has similar composition.After biliary drainage,the abundance of intestinal flora in bile is increased,and the species richness and diversity of the original biliary tract microbial community are decreased,which may explain the clinical phenomenon that patients are more prone to biliary tract infection after biliary drainage.(J Intervent Radiol,2024,33:516-522)

Objective:To investigate the outcomes of surgical treatment for carotid body tumor(CBT) without preoperative embolization at our institution.Methods:101 patients undergoing surgical treatment for CBT without preoperative embolization from 2011 to 2016 were followed-up for 2 years.Results:Complete resection of the CBT was achieved in all 101 cases(100%). Post-operative adverse events(AEs) mostly observed during hospitalization were as tongue bias(Ⅰ: 4, 36.4%; Ⅱ: 8, 19.5%; Ⅲ: 13, 26.5%), hoarseness(Ⅰ: 1, 9.1%; Ⅱ: 4, 9.8%; Ⅲ: 7, 14.3%), dysphagia (Ⅰ: 0; Ⅱ: 2, 4.9%; Ⅲ: 7, 14.3%) and local hematoma(Ⅰ: 0; Ⅱ: 0; Ⅲ: 1, 2.0%). No other serious AEs were observed. The total incidence of AEs was 5(45.5%) in type Ⅰ patients, 14(34.1%) in type Ⅱ, and 28(57.1%) in type Ⅲ. At the end of 2 years of follow-up, there was no AEs in type Ⅰ patients. The number of patients with adverse events in type Ⅲ was greater than that in type Ⅱ ( P>0.05). Three most frequently injured cranial nerves were hypoglossal nerve(21.9%), vagus nerve(20.3%), and recurrent laryngeal nerve(18.8%). Conclusion:Surgical management without preoperative embolization for CBT patients does not increase the risk of complications nor is it related to prognosis.

The eutR gene deletion mutant of Salmonella enteritidis was successfully constructed by homologous recombination.Through the study of its biochemical characteristics,motility,resist-ance to stress in vitro and survival ability in RAW 264.7 cells,it was found that the biochemical characteristics and motility of the eutR gene deletion mutant of Salmonella enteritidis had no sig-nificant change compared with the wild type of Salmonella enteritidis.The ability of eutR gene de-letion strain of Salmonella enteritidis to resist acid,alkali and oxidation was significantly reduced,while the ability to resist heat was not significantly changed;the survival ability of eutR gene dele-tion strain in RAW 264.7 cells was significantly reduced compared with the wild type.In order to further analyze the effect of eutR gene on the expression of virulence factors of Salmonella enterit-idis,the relative expression levels of invH,ssav,ssrA,xthA,orf245,sodC,lrp,mrr1 and hflk virulence genes of the deletion strain and the wild strain were detected by SYBR Green PCR.It was found that the expression of the virulence factors mentioned above in the eutR gene deletion strain of Salmonella enteritidis was significantly down-regulated compared with that in the wild-type strain.The LD50 of the eutR gene-deleted strain of Salmonella enteritidis was determined by ani-mal experiments,and the results showed that the LD50 of the eutR gene-deleted strain was higher than that of the wild-type strain,indicating that the eutR gene could affect the virulence of Salmonella.This study clarified the effect of eutR gene on the survival ability,some biological characteristics and virulence of Salmonella enteritidis in macrophages,and provided a new gene knockout target for the development of attenuated Salmonella enteritidis genetic engineering vac-cine.

There has been increasing interest in research and development of nanocrystals for the delivery of poorly water-soluble drugs that can be directly produced from solution. Compared with traditional carrier-based or encapsulation designs, drug nanocrystals circumvent possible side-effects due to carrier polymers and poor stability issues associated with encapsulation. The production of carrier-free nanocrystals requires careful control of nucleation and thus a thorough understanding of the relevant solution's metastable zone. A solution may stay supersaturated without forming any nuclei and become metastable. The maximal degree of supersaturation is known as the metastable zone width. When nucleation is triggered directly from the metastable zone, it helps to produce homogeneous nuclei leading to uniform nanocrystals. Herein, we report a study in which the solubility and metastable limit of paclitaxel (PTX) in ethanol aqueous solution were measured at 40 °C. A wide range of metastable compositions were studied to prepare carrier-free PTX nanocrystals with particle size smaller than 250 nm and PDI less than 0.25. Compared with the raw material, dissolution rate of PTX nanocrystals was significantly increased. The study enables production of high-quality drug nanocrystals for treating patients.