ABSTRACT
Background@#Brucella infection induces brucellosis, a zoonotic disease. The intracellular circulation process and virulence of Brucella mainly depend on its type IV secretion system (T4SS) expressing secretory effectors. Secreted protein BspJ is a nucleomodulin of Brucella that invades the host cell nucleus. BspJ mediates host energy synthesis and apoptosis through interaction with proteins. However, the mechanism of BspJ as it affects the intracellular survival of Brucella remains to be clarified. @*Objectives@#To verify the functions of nucleomodulin BspJ in Brucella's intracellular infection cycles. @*Methods@#Constructed Brucella abortus BspJ gene deletion strain (B. abortus ΔBspJ) and complement strain (B. abortus pBspJ) and studied their roles in the proliferation of Brucella both in vivo and in vitro. @*Results@#BspJ gene deletion reduced the survival and intracellular proliferation of Brucellaat the replicating Brucella-containing vacuoles (rBCV) stage. Compared with the parent strain, the colonization ability of the bacteria in mice was significantly reduced, causing less inflammatory infiltration and pathological damage. We also found that the knockout of BspJ altered the secretion of cytokines (interleukin [IL]-6, IL-1β, IL-10, tumor necrosis factor-α, interferon-γ) in host cells and in mice to affect the intracellular survival of Brucella. @*Conclusions@#BspJ is extremely important for the circulatory proliferation of Brucella in the host, and it may be involved in a previously unknown mechanism of Brucella's intracellular survival.
ABSTRACT
Objective:To investigate the predictive value of peritoneal protein clearance (Pcl) for cardiovascular events and cardiovascular mortality in peritoneal dialysis (PD) patients.Methods:Eligible PD patients were prospectively enrolled from January 2014 to April 2015 in the PD Center of Renji Hospital, School of Medicine, Shanghai Jiao Tong University. All patients were followed up until death, withdrawing from PD, transferring to other centers, or the end of study period (October 1, 2018). The patients were divided into high Pcl group and low Pcl group by the median Pcl, and the differences of related indicators between the two groups were compared. A multiple linear regression model was used to analyze the influencing factors of Pcl. The Kaplan-Meier method and Log-rank test were used to compare the cumulative survival rates of patients between the two groups. A multivariate Cox regression model was used to estimate the risk of cardiovascular events and cardiovascular mortality in relation to Pcl in PD patients.Results:A total of 271 patients were enrolled, with 135 males (49.8%), age of (56.92±0.84) years old and a median PD duration of 38.77(19.00, 63.10) months. There were 70 patients (25.8%) comorbiding with diabetes and 81 patients (29.9%) with cardiovascular diseases (CVD). The median Pcl of this cohort was 67.93(52.31, 88.36) ml/d. Compared with the low Pcl group (Pcl<67.93 ml/d), the high Pcl group (Pcl≥67.93 ml/d) had older age, and greater proportion of CVD, body mass index (BMI), pulse pressure, brain natriuretic peptide, mass transfer area coefficient of creatinine (MTACcr), and lower serum albumin (all P<0.05). There was no significant difference in gender, dialysis duration, proportion of diabetes, proportion of angiotensin converting enzyme inhibitor and angiotensin receptor blocker, proportion of continuous ambulatory PD, high sensitivity C reactive protein, fluid removal including 24 h urine volume and 24 h ultrafiltration, and residual renal function between the two groups (all P>0.05). Multiple linear regression analysis showed that serum albumin ( β=-0.388, P<0.001), BMI ( β=0.189, P<0.001), and MTACcr ( β=0.247, P<0.001) were independently related to lg(Pcl). During the study period, 55 patients experienced one or more cardiovascular events and 39 patients had cardiovascular mortality. According to Kaplan-Meier analysis, cardiovascular mortality in the high Pcl group was higher than that of low Pcl group (Log-rank χ2=6.902, P=0.009). Multivariate Cox regression analysis showed that, high lg(Pcl) was an independent influencing factor of cardiovascular events in PD patients ( HR=7.654, 95% CI 1.676-34.945, P=0.009). Conclusions:Serum albumin, BMI and MTACcr are independently associated with Pcl, and Pcl is an independent predictor of cardiovascular events in PD patients.
ABSTRACT
Objective:To evaluate the influencing factors of carotid-femoral pulse wave velocity (CF-PWV) and its value to predict outcomes in peritoneal dialysis (PD) patients.Methods:Eligible patients undergoing PD in Renji Hospital of Shanghai Jiao Tong University between August 2016 and July 2018 were recruited and prospectively followed up until death, PD cessation, or to the end of the study. CF-PWV was measured by an arterial pulse wave velocity meter to assess arterial stiffness (July 31, 2020). Overhydration was measured by bioimpedance spectroscopy. The patients were divided into CF-PWV≤10 m/s group and CF-PWV>10 m/s group according to the measured value of CF-PWV. The influencing factors of elevated CF-PWV were analyzed by multivariate logistic regression. Survival curves were generated using the Kaplan-Meier method and multivariate Cox proportional hazards models were used to analyze the difference for all-cause mortality and cardiovascular disease (CVD) mortality between the two groups.Results:A total of 224 PD patients were enrolled, including 133 males (59.4%). The age was (55.2±13.4) years old, and median PD vintage was 22.3(6.5, 59.3) months. Among them, 47(21.0%) patients were comorbid with diabetes, and 37(16.5%) patients had CVD history. The median CF-PWV was 9.6(8.4, 11.4) m/s for the cohort, and 105(46.9%) participants had CF-PWV over 10 m/s. Compared with CF-PWV≤10 m/s group, CF-PWV>10 m/s group patients had older age, increased percentage of diabetes and CVD (all P<0.05). Multivariate logistic analysis showed that increased age ( OR=1.070, 95% CI 1.043-1.099, P<0.001), diabetes ( OR=3.693, 95% CI 1.646-8.287, P=0.002) and higher overhydration ( OR=1.238, 95% CI 1.034-1.483, P=0.020) were independent influencing factors for elevated CF-PWV in PD patients. After followed up for 37.4(25.6, 41.7) months, 24 patients died, including 19 cases of CVD-related deaths. Kaplan-Meier survival analysis showed that all-cause mortality and CVD mortality were significantly higher in the CF-PWV>10 m/s group than those in CF-PWV≤10 m/s group (Log-rank χ2=6.423, P=0.011; Log-rank χ2=6.243, P=0.012, respectively). Multivariate Cox proportional hazards models showed that increased age was an independent influencing factor for both all-cause mortality and CVD mortality ( HR=1.057, 95% CI 1.010-1.107, P=0.018; HR=1.062, 95% CI 1.009-1.118, P=0.022). Conclusions:Increased arterial stiffness is relatively common in PD patients. Higher CF-PWV in PD patients is associated with increased age, diabetes and higher overhydration, and it is probably a valuable predictor of outcome in PD patients.
ABSTRACT
Objective In order to lay the foundation for establishment of a clean grade Meriones meridianus popu-lation, and provide reference for the formulation of Meriones meridianus parasite detection standard.Methods A survey of parasite infection in Meriones meridianus was carried out, and three kinds of antiparasitic drugs, tetramethrin/per-methrin, praziquantel, and tinidazole were used in high-, medium-and low-doses for eradication of the target parasites. Results Three types of parasites were detected among the animals.The infection rate of surface parasite Myobia musculi was 82.1%(23/28), that of intestinal parasite Hymenolepis nana was 78.1% (25/32) and Tritrichomonas muris was 90.6%(29/32).Significant results of parasite eradication were achieved with the antiparasitic drugs.Medicated bath u-sing 1%tetramethrin/permethrin for 30 s every 4 days for 5 times and 1.5%tetramethrin/permethrin for 30 s every 4 days for 3 times completely eradicated the surface Myobia musculi infection.Praziquantel in a dose of 31 mg/kg by daily gastric gavage for consecutive 7 days was the optimal dosage to completely eradicate the intestinal Hymenolepis nana.Tinidazole in a dose of 42 mg/kg administered by gastric gavage daily for consecutive 7 days was the optimal dosage for eradication of in-testinal Tritrichomonas muris infection.Conclusions Three types of parasites are detected in Meriones meridianus in our laboratory, i.e.surface infection with Myobia musculi, and intestinal infection with Tritrichomonas muris and Hymenolepis nana.Tetramethrin/permethrin, praziquantel and tinidazole can be used to effectively eradicate these three types of para-sites, respectively.
ABSTRACT
Objective The purpose of this study was to investigate the reproductive characteristics of indoor-housed Meriones meridianus.Methods According to the data of Meriones meridianus from 1996 to 2002 in the Center for Laboratory Animal research of Xinjiang, the sexual maturity period of male and female animals, the gestation period of female animals, the litter size, weaning rate, survival rate, sex ratio per month and different fetal times were statistically analyzed.Results Sexual maturity period of male and female animals was 109.3 ±21.0 days and 106.3 ±21.7 days, and gestation period of female animals was 21.3 ±1.4 days.The litter size, weaning rate of different fetal times showed no significant difference compared between those of the first to seventh litter ( P>0.05) , and the survival rate of fourth and sixth litter were lower than that of the average offspring per litter, but the difference was no significant (P>0.05).The sex ratio of from first to sixth litter indicated no significant difference ( P>0.05 ) , and the average proportion of male and female was 1.4:1.0.During a year, the animals almost stopped to reproduce from September to November, however, the differences of litter size between the other months were statistically not significant ( P >0.05 ) , the weaning rate and survival rate per month suggested a significant difference ( P <0.05 ) between some of the months.Conclusions Compared with the background data of wild Meriones meridianus, the laboratory reproduction of Meriones meridianus show some differences, mainly, the season of breeding is shifted to December, and the number of reproduction increased by one or two litters.Our results provide useful reference for laboratory animalization of Meriones meridianus.
ABSTRACT
Objective To conduct morphological observation and gene identification of the strain of flagellate iso -lated from Cricetulus migratorius in the Xinjiang Research Center for Experimental Animals .Methods The ileocecal con-tents of C.migratorius were microscopically examined on direct smear with Wright-Giemsa staining , and the total RNA iso-lated from Xinjiang C.migratorius was extracted and 16S rRNA was amplified by PCR , and then sequenced .Furthermore the homology was compared and the phylogenetic tree was developed using MEGA 5.22 software.Results Morphological observation indicated that the isolated flagellate was Tritrichomonas muris.The 16S rRNA gene sequence of the Xinjiang C. migratorius isolate shared highly homology with that of other Tritrichomonas.Phylogenetic tree analysis indicated that the 16S rRNA gene of Xinjiang C.migratorius isolate was classified into a subgroup with T.muris 16S rRNA (U85966.1), but was relatively distant relative from other related tritrichomonas.Conclusions The flagellate isolated from Xinjiang C. migratorius is identified to be T.muris by both morphological observation and 16S rRNA gene analysis.