Planned initiation of extracorporeal membrane oxygenation prior to liver transplantation: a report of 3 cases / 中华器官移植杂志

Objective:To explore the feasibility and advantages of planned initiation of extracorporeal membrane oxygenation(ECMO)prior to liver transplantation.Methods:From November 2017 to July 2021, clinical data were retrospectively reviewed for 3 liver transplantation recipients assisted by ECMO.There were such preoperative symptoms of right ventricular dysfunction as fatigue, chest tightness and palpitations.In the first case, right heart catheterization was not performed due to patient refusal; another two patients were screened by transthoracic Doppler echocardiography(TDE)and diagnosed through right heart catheterization as portopulmonary hypertension(POPH)and pulmonary hypertension.Results:Three recipients with pulmonary hypertension received catheterization in right femoral artery and vein.After freeing of diseased liver and before blocking inferior vena cava, V-A ECMO support was performed.The dose of heparin was adjusted according to activated clotting time(ACT)and perioperative vital signs remained stable.They were ventilated for 54, 12 and 62 hours and supported by ECMO for 27, 61 and 14 hours.All were smoothly discharged.During a mean follow-up period of 26(9-22)months, liver functions were normal.Conclusions:Patients with end-stage liver disease with pulmonary hypertension should undergo routine TDE examinations during waiting period before liver transplantation.Those with pulmonary hypertension should undergo further right heart catheterization to confirm the diagnosis and severity of the disease.Planned application of ECMO through multidisciplinary consultations can expand surgical indications for liver transplantation, maintain intraoperative hemodynamic stability and facilitate smooth liver transplantation and postoperative patient recovery.

Analysis of influencing factors for anastomotic biliary stricture after liver transplantation / 中华消化外科杂志

Objective:To investigate the influencing factors for anastomotic biliary stric-ture after liver transplantation.Methods:The retrospective case-control study was conducted. The clinical data of 428 recipients who underwent allogeneic orthotopic liver transplantation in the First Hospital of Jilin University from September 2014 to August 2021 were collected. There were 324 males and 104 females, aged (52±10)years. Observation indicators: (1) surgical conditions of recipients; (2) occurrence of anastomotic biliary stricture after liver transplantation and its treat-ment; (3) analysis of influencing factors for anastomotic biliary stricture after liver transplantation. Follow-up was conducted using outpatient examination to detect occurrence of anastomotic biliary stricture and treatment up to August 30, 2021. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measure-ment data with skewed distribution were represented as M( Q1, Q3) or M(range), and comparison between groups was analyzed using the Mann-Whitney U test. Count data were represented as absolute numbers, and the chi-square test was used for comparison between groups. Logistic regression model was used for multivariate analysis. Results:(1) Surgical conditions of recipients: the operation time of 428 recipients was 465(420,520)minutes, the cold ischemia time was 368(320,450)minutes, and the volume of intraoperative blood loss was 2 500(1 500,4 000)mL. Of the 428 recipients, 142 cases were performed continuous biliary posterior wall anastomosis + interrup-ted anterior wall anastomosis by polygluconate sutures, 286 cases were anastomosed with polypro-pylene sutures, including 169 cases undergoing continuous biliary posterior wall anastomosis combined with interrupted anterior wall anastomosis, 73 cases undergoing completely interrupted biliary anterior and posterior wall anastomosis, and 44 cases undergoing completely continuous biliary anterior and posterior wall anastomosis. None of the 428 recipients had indwelling T tubes. (2) Occurrence of anastomotic biliary stricture after liver transplantation and its treatment:all the 428 recipients were followed up for 3 to 72 months, with a median follow-up time of 28 months. During the follow-up, 50 patients developed anastomotic biliary stricture, of which 41 patients were treated with endoscopic retrograde cholangiopancreatography, 8 patients were treated with percutaneous transhepatic cholangial drainage, and 1 patient was treated with surgery, showing no recurrence. (3)Analysis of influencing factors for anastomotic biliary stricture after liver transplanta-tion: results of univariate analysis showed that anastomosis method and donor liver cold ischemia time were related factors for postoperative anastomotic biliary stricture of recipients undergoing allogeneic orthotopic liver transplantation ( χ2=15.74, Z=-2.04, P<0.05). Results of multivariate analysis showed that completely interrupted biliary anterior and posterior wall anastomosis and donor liver cold ischemia time were independent influencing factors for postoperative anastomotic biliary stricture of recipients undergoing allogeneic orthotopic liver transplantation ( odds ratio=0.25, 1.00, 95% confidence interval as 0.08-0.85, 1.00-1.01, P<0.05). Conclusions:Suture type is not an influencing factor for postoperative anastomotic biliary stricture of recipients undergoing allogeneic orthotopic liver transplantation. Completely interrupted biliary anterior and posterior wall anastomosis and donor liver cold ischemia time were independent influencing factors.

A wheat NBS-LRR gene TaRGA19 participates in Lr19-mediated resistance to Puccinia triticina.

Wheat leaf rust, caused by Puccinia triticina (Pt), is one of the most severe fungal diseases on wheat globally. Rational utilization of wheat leaf rust resistance (Lr) genes is still the best choice for control this disease. Wheat seedlings carrying Lr19 showed a high resistance phenotype to all Pt races in China. So far, all the cloned seedling Lr genes including Lr1, Lr10 and Lr21, encode protein with NBS-LRR domain. In this study, a wheat gene with NBS-LRR domain from previously established Lr19-resistance-related cDNA library was cloned and designated as TaRGA19. Full length of this gene was amplified by rapid amplification of cDNA ends (RACE). By blast against IWGSC wheat genome database, we have noticed that TaRGA19 was located on chromosome 2DS, which was different from Lr19 located on chromosome 7DL. Compared with susceptible Thatcher line, expression level of TaRGA19 was upregulated in wheat isogenic lines carrying Lr19 (TcLr19) after inoculation of Pt race THTS. By particle bombardment, TaRGA19-GFP fused protein was localized on plasma membrane of epidermal cells. Using virus-induced gene silencing (VIGS), TaRGA19-knockdown plants of TcLr19 showed reduced resistance and few sporulation phenotype upon Pt challenge. Further histological observation indicated that Pt hyphal growth at the infection sites was less suppressed in the TaRGA19-knockdown plants. In conclusion, we speculate this TaRGA19 gene was involved in the Lr19-mediated resistance to wheat leaf rust along with other components.

Construction of nsdAmgh gene disruption mutant in Strempomyces roseoflavus Men-myco-93-63 / 生物工程学报

Insertional mutagenesis is a widely used method to determine the function(s) of a gene. To study the function(s) of the gene nsdAmgh in Streptomyces roseoflavus, a homologous recombination vector pSRNA2500 was structured in this paper. The recombination donor vector was then transformed into Strempomyces roseoflavus strain Men-myco-93-63 by conjugative transfer. The transformants were subjected to selection under the pressure of high temperature and appropriate antibiotics. As a result, several disrupted mutants of nsdAmgh gene, with a phenotype of Am(s)Km(r), were isolated and verified using PCR and Dot-blotting and Southern blotting hybridization methods. Functional analysis showed that the disrupted mutants of nsdAmgh had a two-fold higher inhibition against Verticillium dahlia Kleb than that of the wild strain Men-myco-93-63, which all will provide a new study route for future research about positive and negative regulator in Men-myco-93-63.

[Efficient detection and analysis of linear plasmid in Stremptomyces Men-myco-93-63].

OBJECTIVE: To develop an efficient method to detect and analyze the endogenous plasmid in Stremptomyces Men-myco-93-63. METHODS: According to the property of 'the linear chromosomes and plasmids of Stremptomyces spp.have proteins covalently bound to the 5'ends of the DNA', a novel method was established to detect the type, configuration and size of the Streptomyces spp. plasmids by improving the preparation of agarose embedded block. The method can also show whether the linear plasmids have proteins covalently bound to the DNA from both the positive and negative aspects. RESULTS: The type and configuration of two plasmids were determined efficiently from Stremptomyces roseoflavus Men-myco-93-63 and verified by the two-dimensional electrophoresis. The speculated sizes of these plasmids were 47 kb and 53 kb, respectively. CONCLUSION: Two linear plasmids were detected successfully from Stremptomyces roseoflavus Men-myco-93-63 by a new method.