Protective efficacy of Toxoplasma gondii GRA12 or GRA7 recombinant proteins encapsulated in PLGA nanoparticles against acute Toxoplasma gondii infection in mice.

Background: Toxoplasma gondii is an apicomplexan parasite that affects the health of humans and livestock, and an effective vaccine is urgently required. Nanoparticles can modulate and improve cellular and humoral immune responses. Methods: In the current study, poly (D, L-lactic-co-glycolic acid) (PLGA) nanoparticles were used as a delivery system for the T. gondii dense granule antigens GRA12 and GRA7. BALB/c mice were injected with the vaccines and protective efficacy was evaluated. Results: Mice immunized with PLGA+GRA12 exhibited significantly higher IgG, and a noticeable predominance of IgG2a over IgG1 was also observed. There was a 1.5-fold higher level of lymphocyte proliferation in PLGA+GRA12-injected mice compared to Alum+GRA12-immunized mice. Higher levels of IFN-g and IL-10 and a lower level of IL-4 were detected, indicating that Th1 and Th2 immune responses were induced but the predominant response was Th1. There were no significant differences between Alum+GRA7-immunized and PLGA+GRA7-immunized groups. Immunization with these four vaccines resulted in significantly reduced parasite loads, but they were lowest in PLGA+GRA12-immunized mice. The survival times of mice immunized with PLGA+GRA12 were also significantly longer than those of mice in the other vaccinated groups. Conclusion: The current study indicated that T. gondii GRA12 recombinant protein encapsulated in PLGA nanoparticles is a promising vaccine against acute toxoplasmosis, but PLGA is almost useless for enhancing the immune response induced by T. gondii GRA7 recombinant protein.

[Distribution of pathogenic bacteria in patients of injuries combined with infection after May 12 Wenchuan Earthquake and drug resistance thereof].

OBJECTIVE: To investigate the distribution of pathogenic bacteria in the patients of injuries combined with infection after May 12 Wenchuan Earthquake and the drug resistance thereof. METHODS: Bacterial culture and identification were conducted on 139 clinical specimens from 108 patients with open injuries combined with infection. Drug-sensitive test was carried out by Kirby-Bauer method on the isolated strains. RESULTS: Ninety-six stains were isolated, 79.86% of them were from the infected wound secretion and 58.33% were from three department of orthopedics. The bacteria with high isolation rates included Acinetobacter spp. (20 strains), Enterobacter cloacae (20 strains), Escherichia coli (17 strains), and Staphylococcus spp. (13 strains). The isolated Gram negative bacteria showed lower resistance to imipenem, amikacin, and cefoperazone/sulbactam. CONCLUSION: The Gram negative bacteria isolated from the wounds caused by earthquake show lower resistance to imipenem, amikacin, and cefoperazone/sulbactam. No Staphylococcus spp. is found resistant to glycopeptides.

[Transthoracic echocardiography in transcatheter closure of atrial septal aneurysm combined with secoundum-type atrial septal defect].

OBJECTIVE: To explore the value of transthoracic echocardiography (TTE) in transcatheter closure of atrial septal aneurysm (ASA) combined with secoundum-type atrial septal defect (ASD). METHODS: Fourteen patients (3 males and 11 females) who had ASA combined with secoundum-type ASD were diagnosed by TTE or transesophageal echocardiography. The ASA projected to the right atrium in all patients. The width of basilar part was 13 approximately 24 (18.5+/-3.9) mm, and the vertical extent was 7 approximately 11(9.7+/-1.8) mm. Ten patients combined with single hole ASD and 4 patients with multiple hole ASD. Blood shifting from the left atrium to the right atrium was displayed in color Doppler in all patients. All patients were treated by transcatheter closure under the guiding of X fluoroscopy and TTE, and examined with TTE during the follow-up. RESULTS: Transcatheter closure was successfully performed by 14 occluders in all patients. No residual shunt was detected immediately by TTE after the procedure in all patients. During the 6 approximately 12 month follow-up, no residual shunt or occluder shifting was found, the dimensions of the heart became normal in 11 patients (79%) and were significantly decreased in 4. CONCLUSION: Transcatheter closure is feasible in patients with ASA combined with secoundum-type ASD, and extra attention must be paid to the specialty. TTE is very important in case selection before transcatheter closure, and it may be used to monitor and guide the procedure during transcatheter closure.

[Short and mid-term effects of percutaneous transcatheter closure of ventricular septal defects on the cardiac remodeling].

OBJECTIVE: To evaluate the short and mid-term changes of the cardiac morphology after percutaneous transcatheter closure of ventricular septal defects (VSD) with transthoracic echocardiography (TTE). METHODS: The left ventricular end-diastolic diameter (LVEDD), left ventricular end-diastolic volume (LVEDV), left atrial diameter (LAd), and right ventricular diameter (RVd) in 30 VSD patients were measured before the VSD closure,and on the 3rd day, 3rd month, and 6th month after the VSD closure by TTE. RESULTS: LVEDD and LVEDV significantly decreased on the 3rd day after the VSD closure compared with pre-VSD closure. LVEDD and LVEDV continuously decreased on the 3rd month and 6th month after the VSD closure. LAd was smaller on the 3rd month and 6th month after the VSD closure, but there was not significant difference between the 3rd and 6th month. RVd increased on the 3rd day after the VSD closure, while no significant difference was found among the 3rd month and 6th month before and after VSD closure. CONCLUSION: Percutaneous transcatheter VSD closure may effectively improve the cardiac remodeling in VSD patients in the short and mid-term follow-up.

[Serum level of homocysteine and the development of collateral circulation in patients with severe coronary artery stenosis].

OBJECTIVE: To investigate the relationship between serum level of homocysteine and the development of collaterals in patients with severe coronary artery stenosis (SCAS). METHODS: Eighty patients with at least one vessel stenosis over 90% among the 3 main vessels of coronary artery were consecutively enrolled into the study according to angiographic estimation. The development of collaterals was classified by Rentrop's method. RESULTS: The serum levels of homocysteine among the single-vessel, bi-vessel and tri-vessel coronary artery disease groups had no significant difference; there was no linear correlation between the serum level of homocysteine and Gensini's score. The level of homocysteine in the poorly developed collaterals was significantly higher than that in the well-developed collaterals in the SCAS patients (P<0.001). Multiple stepwise logistic analysis revealed that homocysteine negatively correlated with the development of collaterals (P<0.001, odds ratio=0.353; 95% confidence interval=0.201 - 0.620), whereas it positively correlated with the number of stenosis vessels. CONCLUSION: The serum level of homocysteine is independently and negatively associated with the development of collateral circulation in severe SCAs patients.

Improving the management of anemia in hemodialysis patients by implementing the continuous quality improvement program.

BACKGROUND: Anemia is common in hemodialysis patients, and improvement in anemia management is possible with the implementation of continuous quality improvement (CQI) programs. The aim of this study is to improve anemia management in chronic hemodialysis patients using CQI. METHODS: Ninety hemodialysis patients in our single center were enrolled in the study. The patients were followed up from January 2004 to October 2005. The CQI team-oriented approach was driven by a process called the 'FOCUS-PDCA cycle plan' (find, organize, clarify, uncover, start, plan, do, check and act). Hemoglobin (Hb), serum ferritin and transferrin saturation were monitored periodically. RESULTS: By implementation of the CQI program, the proportion of patients with Hb >or=110 g/l increased from 42.2 to 60.0% (p < 0.05), and the Hb level increased from 101.2 +/- 18.05 to 110.4 +/- 14.23 g/l (p < 0.0001). The proportion of patients with an adequate iron status increased from 28.0 to 53.3% (p < 0.05). CONCLUSION: The CQI program is a useful method in the management of anemia in hemodialysis patients.

[Formation and function of coronary collateral circulation and their influencing factors].

OBJECTIVE: To clarify the formation and function of coronary collateral circulation (CCC) in coronary artery disease (CAD) patients with severe coronary artery stenosis and their influencing factors. METHODS: Coronary angiography was performed on 266 CAD patients with severe coronary stenosis. CCC formation was evaluated by Rentrop rating on those 266 patients and 401 severe stenosis arteries; while in CCC formed patients, CCC function was evaluated by Werner collateral collection (CC) rating. The formation, function of CCC and their influencing factors were analyzed and compared. RESULTS: CCC formation in those severe stenosis coronary arteries was related to the severity of coronary stenosis: the forming rate of CCC was 42.6% in vessels with 90%-94% stenosis (Group A), 56.9% with 95%-99% stenosis (Group B) and 93.0% with 100% stenosis (Group C) (p <0 .01). Between CCC forming and non-forming groups, there was no significant difference in age, gender, incidence of MI, hypertension and diabetes, history of smoking and serum levels of HDL-C and LDL-C (P > 0.05). In the CCC formation group, serum HDL-C level was the highest in the CC Grade 2 group (according to Werner function rating) and the lowest in the CC Grade 0 group (P < 0.05). Whereas, LDL-C level was the lowest in the CC Grade 2 group and the highest in the CC Grade 0 group (P < 0.05). CONCLUSION: Severity of coronary stenosis was the major influencing factor in CCC formation and function, and the rate of CCC formation increased with the exacerbation of coronary stenosis. Serum HDL-C and LDL-C level had no relationship with CCC formation, but related to CCC function. Better CCC function was found in patients with high level of HDL-C whereas the patients with high level of LDL-C had spoiled CCC function.