Identification and characterization of a Streptococcus suis immunogenic ornithine carbamoytransferase involved in bacterial adherence.

BACKGROUND: Streptococcus suis (SS) is a major swine pathogen and a serious zoonotic pathogen causing septicemia and meningitis in piglets and humans. Using an immunoproteomic approach, we previously brought evidence that ornithine carbamoytransferase (OCT) may represent a vaccine candidate to protect against S. suis biofilm-related and acute infections. METHOD: In this study, the gene encoding OCT was cloned into the expression vector pET-28a and the recombinant protein was expressed in Escherichia coli BL21. The immunogenicity and protective efficacy of the SS OCT was further investigated in a mouse model. RESULTS: The protein was found to be expressed in vivo and elicited high antibody titers following SS infections in mice. An animal challenge experiment with SS showed that 62.5% of mice immunized with the OCT protein were protected. Using an in vitro competitive adherence inhibition assay of adherence, evidence was obtained that OCT could significantly reduce the number of SS cells adhered to porcine kidney PK-15 cells. The bacterial levels recovered in mice of the OCT immunized group were significantly decreased in some organs, compared with the control group. CONCLUSION: In summary, our results suggest that the recombinant SS OCT protein, which is involved in bacterial adherence, may efficiently stimulate an immune response conferring protection against SS infections. It may therefore be considered as a potential vaccine candidate, although further studies are necessary to evaluate their use in swine.

Effects of Modafinil on Behavioral Learning and Hippocampal Synaptic Transmission in Rats / 대한배뇨장애요실금학회지

PURPOSE: Modafinil is a wake-promoting agent that has been proposed to improve cognitive performance at the preclinical and clinical levels. Since there is insufficient evidence for modafinil to be regarded as a cognitive enhancer, the aim of this study was to investigate the effects of chronic modafinil administration on behavioral learning in healthy adult rats. METHODS: Y-maze training was used to assess learning performance, and the whole-cell patch clamp technique was used to assess synaptic transmission in pyramidal neurons of the hippocampal CA1 region of rats. RESULTS: Intraperitoneal administration of modafinil at 200 mg/kg or 300 mg/kg significantly improved learning performance. Furthermore, perfusion with 1mM modafinil enhanced the frequency and amplitude of spontaneous postsynaptic currents and spontaneous excitatory postsynaptic currents in CA1 pyramidal neurons in hippocampal slices. However, the frequency and amplitude of spontaneous inhibitory postsynaptic currents in CA1 pyramidal neurons were inhibited by treatment with 1mM modafinil. CONCLUSIONS: These results indicate that modafinil improves learning and memory in rats possibly by enhancing glutamatergic excitatory synaptic transmission and inhibiting GABAergic (gamma-aminobutyric acid-ergic) inhibitory synaptic transmission.

Quantitative evaluation of cardiopulmonary functional reserve in treated patients with pulmonary embolism / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There is no research, either at home or abroad, focusing on assessing the cardiopulmonary functional reserve and exercise tolerance in patients with pulmonary embolism (PE), but the benefits of early exercise are well recognized. The goals of this study were to assess cardiopulmonary functional reserve in treated PE patients using the inert gas rebreathing method of the cardiopulmonary exercise test (CPET), and to compare it with traditional methods.</p><p><b>METHODS</b>CPET on the bicycle ergometer were performed in 40 patients with age, gender, body mass index, systolic blood pressure, and pulmonary function matched. The first group was the PE group composed of 16 PE patients (5 male, 11 female) who were given the standard antithrombotic therapy for two weeks. The second group was composed of 24 normal individuals (10 male, 14 female). Both groups were evaluated by cardiac ultrasound examination, 6-minute walking test (6MWT), and CPET.</p><p><b>RESULTS</b>(1) Right ventricular systolic pressure (RVSP) in the PE group increased significantly compared to the control group, (34.81 ± 8.15) mmHg to (19.75 ± 3.47) mmHg (P < 0.01). But neither right atrial end-systolic diameter (RASD) nor right ventricular end-diastolic diameter (RVDD) in the PE patients had changed when compared with the controls. The 6-minute walk distance was significantly reduced in the PE patients compared with normal subjects, (447.81 ± 79.20) m vs. (513.75 ± 31.45) m (P < 0.01). Both anaerobic threshold oxygen consumption (VO(2)AT) and peak oxygen consumption (VO(2)peak) were significantly lower in patients with PE, while CO(2) equivalent ventilation (VE/VCO(2) slope) was higher; VO(2)AT (9.44 ± 3.82) ml×kg(-1)×min(-1) vs. (14.62 ± 2.93) ml×kg(-1)×min(-1) (P < 0.01) and VO2peak (12.26 ± 4.06) ml×kg(-1)×min(-1) vs. (23.46 ± 6.15) ml×kg(-1)×min(-1) (P < 0.01) and VE/VCO(2) slope 35.47 ± 6.66 vs. 26.94 ± 3.16 (P < 0.01). There was no significant difference in resting cardiac output (CO) between the PE and normal groups, whereas peak cardiac output (peak CO) and the difference between exercise and resting cardiac output (ΔCO) were both significantly reduced in the PE group; peak CO (5.97 ± 2.25) L/min to (8.50 ± 3.13) L/min (P < 0.01), ΔCO (1.29 ± 1.59) L/min to (3.97 ± 2.02) L/min (P < 0.01). (2) The 6-minute walk distance did not correlated with CPET except for the VO2 peak in patients with PE, r = 0.675 (P < 0.01).</p><p><b>CONCLUSIONS</b>The cardiopulmonary functional reserve was reduced in patients with PE. CPET is an accurate, quantitative evaluation of cardiopulmonary functional reserve for PE patients.</p>

The effects of aerobic exercise on cardiac output during exercise in patients with chronic heart failure / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the effects of aerobic exercise on cardiac output during exercise in patients with chronic heart failure (CHF).</p><p><b>METHODS</b>A total of 50 CHF patients (echocardiography measured left ventricular ejection fraction < 0.49) were enrolled in the study and randomly divided into aerobic exercise group (n = 25) and control group (n = 25). Cardiopulmonary exercise testing (CPET) was performed. Patients of aerobic exercise group underwent aerobic exercise according to aerobic exercise prescription and exercise intensity is decided by anaerobic threshold before 10 J/s (1 minute before) of the oxygen consumption. After 6 supervised aerobic exercise training sessions in the hospital, patients were asked to perform the home-based aerobic exercise training. Patients in control group were required to maintain daily physical activities. CPET were reviewed 3 months later.</p><p><b>RESULTS</b>Cardiac output (CO), peak CO, peak cardiac power output (peak CPO), resting heart rate (HR), heart rate at AT (HRAT), HR peak, resting mean arterial pressure (MAP), peak MAP at baseline were similar between aerobic exercise group and control [(4.2 ± 2.0) L/min vs. (3.3 ± 1.0) L/min, (6.2 ± 2.7) L/min vs. (5.2 ± 1.8) L/min, (1.8 ± 2.9) L/min vs. (2.0 ± 1.8) L/min, (1.3 ± 0.5) J/s vs. (1.2 ± 0.5) J/s, (76.8 ± 13.5) beats/min vs. (73.4 ± 11.9) beats/min, (91.5 ± 11.3) beats/min vs. (92.6 ± 12.4) beats/min, (106.0 ± 12.9) beats/min vs. (108.3 ± 17.4) beats/min, (80.8 ± 9.9) mm Hg (1 mm Hg = 0.133 kPa) vs. (87.6 ± 13.3) mm Hg, (98.8 ± 12.4) mm Hg vs. (102.7 ± 13.9) mm Hg, all P > 0.05]. Compared to baseline, CO, peak CO, peak CPO, HR, HRAT, HR peak, MAP, peak MAP after 3 months were similar between aerobic exercise group and control (all P > 0.05). The differences between baseline and 3 months later expressed as ΔCO, Δpeak CO, Δpeak CPO, ΔHR, ΔHRAT, ΔHR peak, ΔMAP, Δpeak MAP were also similar between aerobic exercise group and control group [(-0.7 ± 2.4) L/min vs. (0.7 ± 2.0) L/min, (1.1 ± 2.6) L/min vs. (1.4 ± 2.1) L/min, (0.1 ± 3.7) L/min vs. (-0.2 ± 2.5) L/min, (0.2 ± 1.0) J/s vs. (0.2 ± 0.5) J/s, (-0.4 ± 7.6) beats/min vs. (1.9 ± 9.9) beats/min, (3.4 ± 11.3) beats/min vs. (-2.8 ± 7.6) beats/min, (8.9 ± 14.5) beats/min vs. (3.7 ± 14.4) beats/min, (1.5 ± 12.8) mm Hg vs. (-1.3 ± 11.1) mm Hg, (6.4 ± 18.9) mm Hg vs. (1.3 ± 12.3) mm Hg, all P > 0.05].</p><p><b>CONCLUSION</b>Three months aerobic exercise training did not improve cardiac output and related parameters during exercise in this cohort patients with CHF.</p>

Bursin as an adjuvant is a potent enhancer of immune response in mice immunized with the JEV subunit vaccine.

Adjuvants play an important role in the formulation of effective and appropriate vaccines. A series of synthetic bursin and bursin-like peptides was heterologously expressed in Escherichia coli. The use of bursin as an adjuvant enhanced the specific immune responses of mice immunized with a recombinant Japanese encephalitis virus E-binding domain (JEV E-BD) fusion protein. The effect was determined in the form of protective anti-JEV E titers, antibodies (IgG1 and IgG2a), spleen cell lymphocyte proliferation, the levels of interferon-gamma and interleukin-4 cytokines, and the T-lymphocyte sub-type composition. The IgG2a titer and interferon-gamma level suggested that the E-BD protein potentiates the Th1 immune response. These responses were changed when the immunogen was combined with one of the synthetic peptides as adjuvant. JEV-neutralization assay results show that the presence of bursin significantly enhance the JEV-neutralizing titer. We conclude that bursin as an adjuvant is a potent enhancer of immune response in mice immunized with the JEV subunit vaccine, and represents a promising adjuvant for vaccination.