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A Pseudomonas exotoxin (PE-KDEL)-based chimeric subunit vaccine system was recently developed using a reverse vaccinology technique. In this study, the plasmids containing PE-PRRS chimeric subunits were constructed that composed of porcine reproductive and respiratory syndrome virus (PRRSV) antigen moieties, a ligand moiety and a Pseudomonas exotoxin A deleted domain III (PE (ΔIII)), and a carboxyl terminal moiety that includes a polypeptide with amino acid sequence KDEL (K3). The PE-PRRS combination vaccine can effectively induce not only PRRSV-specific INF-γ cellular immunity but also a slow-reacting and complement-requiring type serum neutralizing antibody in pigs. In a specific pathogen free (SPF) pig challenge model, body temperature (colonic temperature), occurrence of PRRSV viremia, nasal excretions, gross and histopathological appearances of pneumonia, and serum antibody activity (IFA and SN) titers significantly differed between the immunized group and the control group. The survey showed that a 0.3mg/dose PE-PRRS vaccine formula conferred protection against PRRSV. A field trial of PE-PRRS vaccine was performed to study the immune response of pregnant sows after vaccination in a PRRSV persist farm. The RT-PCR analysis of viremia and serological titers showed that the PE-PRRS vaccine not only increased sow reproductive performance and evoked its immune response to PRRS viremia, it also activated maternal immune protections to prevent piglets from inflicting viremia. In conclusion, we developed a novel and effective PRRS cytotoxic T-cells (CTLs)-based vaccine containing Pseudomonas exotoxin (PE-KDEL) carrier in combination with PRRSV conserved epitopes against PRRS virus.

Maternal seizure has adverse effects on brain histology as well as on learning and memory ability in progeny. An enriched environment (EE) is known to promote structural changes in the brain and improve cognitive and motor deficits following a variety of brain injuries. Whether EE treatment in early postnatal periods could restore cognitive impairment induced by prenatal maternal seizure is unknown. Adult female Sprague-Dawley rats were randomly separated into two groups and were injected intraperitoneally either saline or pentylenetetrazol (PTZ) for 30 days. Then the fully kindled rats and control animals were allowed to mate. PTZ administration was continued until delivery, while the control group received saline at the same time. After weaning at postnatal day 22, one-half of the male offspring in the control and in the prenatal maternal group were given the environmental enrichment treatment through all the experiments until they were tested. Morris water maze testing was performed at 8 weeks of age. Western blot and synaptic ultrastructure analysis were then performed. We found that EE treatment reversed spatial learning deficits induced by prenatal maternal seizure. An EE also reversed the changes in synaptic ultrastructure following prenatal maternal seizure. In addition, prenatal maternal seizure significantly decreased phosphorylation states of cAMP response element binding (CREB) in the hippocampus, whereas EE reversed this reduced expression. These findings suggest that EE treatment on early postnatal periods could be a potential therapy for improving cognitive deficits induced by prenatal maternal seizure.

Cognitive dysfunction is commonly observed in epileptic patients. It has been shown that not only epilepsy but also antiepileptic drugs could induce cognitive impairment. Thus, there is an urgent need for drugs that can suppress seizures without causing cognitive deficit. Recent studies have shown that oxidative stress is involved in the pathophysiology of epilepsy, and many antioxidants have an antiepileptic property. Epigallocatechin-3-gallate (EGCG), a catechin polyphenols component, is found to be an effective antioxidant. The purpose of this study was to assess the effect of EGCG against seizures, seizure-induced oxidative stress and cognitive impairment in pentylenetetrazole-induced kindling. Male Sprague-Dawley rats were injected intraperitoneally with a dose of 35 mg/kg of pentylenetetrazole (PTZ) once every alternate day for 13 injections. EGCG was administered daily in two doses (25mg/kg and 50mg/kg) intraperitoneally along with alternate-day PTZ. Morris water maze test was carried out 24h after the last injection of PTZ, and the oxidative stress parameters (malondialdehyde and glutathione) were assessed after the completion of the behavioral test. The results showed that EGCG dose-dependently suppressed the progression of kindling. EGCG also ameliorated the cognitive impairment and oxidative stress induced by PTZ kindling. These observations suggest that EGCG may be a potential agent for the treatment of epilepsy as well as a preventive agent against cognitive impairment induced by seizure.

To assess the effects of propofol treatments at different time points on acute lung injury and on the expression of transforming growth factor (TGF)-beta1 and the downstream target of TGF-beta1, Smad 2, in the lung tissues in the endotoxic rats.Seventy-six Wistar rats were randomly assigned to five groups: control group (saline only), endotoxemic group [lipopolysaccharide (LPS) 8 mg kg(-1), i.v.], and three propofol-treated groups. For the propofol-treated groups, propofol (5 mg kg(-1), i.v. bolus) was administered either 1 h before LPS, simultaneously with LPS, and 1 h after LPS, and all were followed by infusion of 10 mg kg(-1) h(-1) of propofol for 5 h after LPS. Lung tissues were sampled to measure myeloperoxidase activity and expression of TGF-beta1 and Smad2 and to assess pulmonary microvascular permeability and histopathological changes.The hemodynamics, arterial blood gases, 5 h survival rate, pulmonary microvascular permeability, and acute lung injury scores were significantly better, and expression of TGF-beta1 and Smad2 and myeloperoxidase activity in lung tissues was significantly lower in the pretreatment and simultaneous treatment groups compared to the endotoxemic group. However, there were no significant differences in all observed variables between the endotoxemic and postreatment groups. Except for TGF-beta1 expression in lung tissues, the other observed variables were also not significantly different between the pretreatment and simultaneous treatment groups.In the endotoxic rat model, pretreatment and simultaneous treatment with propofol provided protection against acute lung injury by inhibiting the TGF-beta1-Smad2 dependent pathway.

PNAS-4, a novel pro-apoptotic gene activated during the early response to DNA damage, can inhibit proliferation via apoptosis when overexpressed in some tumor cells. The objectives of this study were to determine whether PNAS-4 could enhance apoptosis induced by cisplatin besides its induction of apoptosis, and to evaluate the usefulness of combined treatment with mouse PNAS-4 (mPNAS-4) gene therapy and low-dose cisplatin chemotherapy in the inhibition of tumor growth in colon carcinoma (CT26) and Lewis lung carcinoma (LL/2) murine models.In this study, the in vitro growth-inhibitory and pro-apoptotic effects of PNAS-4 and/or cisplatin on CT26, LL/2, and SKOV3 cancer cells were assessed by MTT assay, flow cytometric analysis, DNA fragmentation, and morphological analysis, respectively. The in vivo antitumor activity of combined treatment with mPNAS-4 gene therapy and low-dose cisplatin were evaluated in the inhibition of tumor growth in colon carcinoma (CT26) and Lewis lung carcinoma (LL/2) murine models. Tumor volume and survival time were observed. Induction of apoptosis was also assessed in tumor tissues.In vitro, PNAS-4 inhibited proliferation of colon carcinoma (CT26), Lewis lung carcinoma (LL/2) and human ovarian cancer (SKOV3) cell lines via apoptosis, and significantly enhanced the apoptosis of CT26, LL/2, and SKOV3 cells induced by cisplatin. In vivo systemic administration of expression plasmid encoding mPNAS-4 (pcDNA3.1-mPS) and cisplatin, significantly decreased tumor growth through increased tumor cell apoptosis compared to treatment with mPNAS-4 or cisplatin alone.Our data suggests that the combined treatment with mPNAS-4 plus cisplatin may augment the induction of apoptosis in tumor cells in vitro and in vivo, and that the augmented antitumor activity in vivo may result from the increased induction of apoptosis. The present study may provide a novel way to augment the antitumor efficacy of cytotoxic chemotherapy.

To investigate the effects of different fluid resuscitation regimes on lung injury and expression of pulmonary aquaporin 1 (AQP1) and AQP5 in rats with uncontrolled hemorrhagic shock.Sixty Sprague-Dawley (SD) rats were randomly assigned to the following five groups: control group (C group), no fluid resuscitation group (NF group), lactated Ringer's solution group (LRS group), 7.5%NaCl group (HS group) and hydroxyethyl starch group (hydroxyethyl starch 130/0.4, HES group). A four-phased uncontrolled hemorrhagic shock model was reproduced. Uncontrolled hemorrhagic shock phase began with blood withdrawal extended over 15 minutes, in which animals were subjected to massive hemorrhage [mean arterial pressure (MAP)=40 mm Hg (1 mm Hg=0.133 kPa)] for 60 minutes and followed by intratracheal lipopolysaccharide 2 mg/kg and continuous bleeding with amputation of the tail. Then, animals were partially resuscitated with LRS of 3 times the volume of shed blood (LRS group), followed by a bolus dose of 4 ml/kg body weight of 7.5%NaCl (HS), or hydroxyethyl starch (a volume equal to that of the shed blood), respectively, during different fluid resuscitation regimes. After that, comprehensive resuscitation phase of 60 minutes began with hemostasis, and transfusion of all the shed blood plus same amount of normal saline. Observation phase was continued for 3.5 hours. At the end the experiment, the lung tissue was sampled to measure wet-to-dry lung weight ratio (W/D), and the expression of AQP1 and AQP5 were determined with immunohistochemistry. The paraffin-embedded lungs were stained with hematoxylin and eosin for pathological analysis.When compared with NF and LRS groups, the lung W/D ratio was significantly decreased, and the shock induced decreased expression of AQP1 and AQP5 in lung tissue were attenuated in HES group, but these beneficial effects were blunted in the HS group.Uncontrolled hemorrhagic shock may induce lung injury and pulmonary edema as well as down regulation of the expression of AQP1 and AQP5 in rats. Resuscitation with hypertonic fluids, especially with HES, can reduce lung damage and pulmonary edema in this kind of shock. The cause may be due in part to maintenance of the expression of AQP1 and/or AQP5 in the lung. Pulmonary AQP1 and AQP5 play an important role in fluid transportation.

To investigate the changes in pulmonary transforming growth factor-beta1 (TGF-beta1)/smad2 signaling pathway in pulmonary injury as a result of hemorrhagic shock followed by lipopolysaccharide challenge.Twenty-four Sprague-Dawley (SD) rats were randomly assigned to the following two groups: sham operation group (sham group, surgery, no hemorrhage and no resuscitation), and two-hit model group (HS group), each n=12. Three-phased uncontrolled hemorrhagic shock model was reproduced in rats. Hemorrhagic shock phase I began with blood withdrawal over 15 minutes, i.e. animals were subjected to massive hemorrhage [mean arterial pressure (MAP)=35-40 mm Hg (1 mm Hg=0.133 kPa) for 60 minutes], followed by intratracheal lipopolysaccharide 2 mg/kg (two-hit model). Ninety minutes after blood shedding, resuscitation phase II of 60 minutes began with hemostasis, return of all the blood initially shed, plus fluids. Observation phase III was 210 minutes. After phase III, blood gas analysis with carotid artery blood was performed. Lung tissue was sampled to measure values of wet-to-dry lung weight (W/D) ratio and pulmonary microvascular permeability. Immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to assess the expression of TGF-beta1 protein and mRNA, and the protein content of the smad2 was determined by Western blotting.Compared with sham group, MAP was significantly lowered after 60 minutes in phase I, and lactic acid content was increased significantly, while partial pressure of oxygen in artery (PaO2), blood pH, HCO(-)3, arterial oxygen saturation (SaO2) and negative base excess (BE) showed a significant decrease in HS group. Concomitantly, values of pulmonary microvascular permeability and W/D ratio were significantly increased in HS group (all P0.01). In sham group, weak TGF-beta1 staining was detected in the alveolar epithelial cells. However, intense positive immunostaining for TGF-beta1 was observed in alveolar epithelial cells, pulmonary interstitial inflammatory cell as well as macrophage cells of alveolar space of the HS group. Lung tissue in HS group demonstrated a marked increase in TGF-beta1 mRNA and smad2 protein expression in the lung tissue compared with those of sham group (all P0.01).The expression of TGF-beta1/smad2 signaling pathway may play an important role in regulation of pulmonary permeability and development of pulmonary edema in acute lung injury induced by uncontrolled hemorrhagic shock followed by lipopolysaccharide challenge.

To explore the spatial distribution character of dengue fever and the change of Aedes' population, so as to provide macroscopical decision-making evidences of prevention and supervision on dengue fever.(1) Collecting data on morbidity of dengue and supervision on vector's population in the corresponding period. (2) Drawing digitized map of Chaozhou in scale of 1:50,000, including elements of boundary, residential areas, road and traffic, altitude, water systems etc. (3) Measuring the latitude and longitude of center position of surveillance safes on the scene. (4) Processing spatial analysis by the ArcGIS 8.5 software.Distribution of Aedes showed spatial cluster in Chaozhou, while its density was related to the distance to the watersides. The closer to the watersides, the higher the density was. Map on spatial distribution showed that although the Aedes epidemic situation changed yearly, but primarily be kept in high, middle, low regions. Cross-validation effects of the distribution maps were satisfactory.Geographic information system was promising in analyzing data on dengue fever, and better than other routine research methods.