Deep Parasternal Intercostal Plane Block for Intraoperative Pain Control in Cardiac Surgical Patients for Sternotomy: A Prospective Randomized Controlled Trial

OBJECTIVES

Sternotomy pain is common after cardiac surgery. The deep parasternal intercostal plane (DPIP) block is a novel technique that provides analgesia to the anterior chest wall. The aim of this study was to investigate the analgesic effect of bilateral DPIP blocks on intraoperative pain control in cardiac surgery.

DESIGN

This is a double-blinded, prospective randomized controlled trial (Oct 2020-Dec 2022).

SETTINGS

This study was conducted in a single institution, which is an academic university hospital.

PARTICIPANTS

Eighty-six elective cardiac surgical patients with median sternotomy were recruited.

INTERVENTIONS

Patients were randomly divided into DPIP or control group. Either 20ml 0.25% levobupivacaine or 0.9% normal saline was injected for the DPIP under ultrasound guidance after induction of general anaesthesia.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was intraoperative opioids consumption and hemodynamic changes at sternotomy. Secondary outcomes included postoperative morphine consumption, postoperative pain and time to tracheal extubation. Intraoperative opioids requirement was reduced from a median (IQR) intravenous morphine equivalence of 21.4mg (13.8-24.3mg) in control group to 9.5mg (7.3-11.2mg) in the DPIP group (P<0.001). Hemodynamic parameters were more stable in DPIP group at sternotomy, as evidenced by lower percentage increase in systolic, diastolic and mean arterial blood pressure from baseline. No difference was observed in time to tracheal extubation, postoperative morphine consumption, postoperative pain score and spirometry.

CONCLUSIONS

Bilateral DPIP block provides effective intraoperative analgesia and opioid-sparing. It may be included as part of the multimodal analgesia for enhanced recovery in cardiac surgery.

[Visual analysis of the current research status and hotspots of electric burns at home and abroad]

Objective: To analyze the literature on electric burns published at home and abroad, and to explore the research hotspots and frontiers of electric burns. Methods: The bibliometric method was used. The Chinese and English literature related to electric burns published in China National Knowledge Infrastructure, Wanfang database, VIP database and the core collection of Web of Science database from January 1, 2013 to December 31, 2022 were searched respectively, and the CiteSpace 6.2.R2 software was used for analysis. The number of papers, authors, countries, and institutions of Chinese and English literature were counted respectively, and the co-occurrence analysis of keywords and mutation analysis and cluster analysis on the basis of the co-occurrence analysis were conducted, besides, the clustering time line figure was obtained after the keywords were sorted by time to explore the current research status and the evolution process of hotspots in the field of electric burns. Results: A total of 398 English papers were retrieved from the core collection of Web of Science database, and a total of 523 Chinese papers were retrieved from China National Knowledge Infrastructure, Wanfang database, and VIP database after duplicate check. From 2013 to 2022, the number of English literature published in the field of electric burns showed a steadily upward trend, and the number of published Chinese literature showed a downward trend and tended to be stable. In Chinese literature, a total of 302 authors as the first author published papers related to electric burns, with 17 core authors published ≥3 papers; in English literature, a total of 320 authors as the first author published papers related to electric burns. Researches on electric burns were carried out in 65 countries, with United States having the most cooperation with other countries and the largest number of papers published. A total of 512 institutions at home and abroad published papers related to electric burns, and the institutions with the largest number of Chinese and English papers were Shanghai Electric Power Hospital in China (n=14) and Hallym University in Korea (n=11), respectively. A total of 1 176 Chinese keywords and 1 068 English keywords were included for co-occurrence analysis after excluding keywords related to the searching words. The top three keywords in frequency in Chinese literature were surgical flap, wound repair, and nursing, and the top three keywords in frequency in English literature were management, epidemiology, and children. Ten clusters were obtained by keyword analysis in Chinese literature, and the largest cluster was wound healing, followed by clinical effects and surgical flaps. Seven clusters were obtained by keyword analysis in English literature, and the largest cluster was reconstructive surgical procedures, followed by chronic pain and shock. The persistent clusters in Chinese literature were wound healing and clinical outcomes, etc., and the prominent nodes in the recent two years were surgical timing, limb electric burns, and hypertrophic scars; the persistent clusters in English literature were reconstructive surgical procedures and chronic pain, etc., and the prominent nodes in the recent two years were predictors and burn management, etc. In Chinese literature, the keyword with the longest duration of mutation (2017-2021) was wrist electric burns, and the keyword with the highest intensity of mutation was flap repair; in English literature, the keyword with the longest duration of the mutation (2019-2022) was voltage, and the keyword with the highest intensity of mutation was prevention. Conclusions: There are similarities and differences in the research directions and hotspots of electric burns at home and abroad. Surgical flap repair is a common research hotspot at home and abroad. At present, domestic research focuses on wound healing, wrist electric burns, and other aspects, while international research focuses on treatment management, epidemiology, reconstruction, and other aspects.

Tumor Voxel Dose-Response Matrix Prediction Using Deep Learning

PURPOSE/OBJECTIVE(S)

Tumor voxel dose-response matrix (DRM) can be assessed using a series of FDG-PET/CT feedback images acquired during radiotherapy. Predicting the tumor voxel DRM earlier is crucial for effectively implementing adaptive treatment management. However, it is also challenging due to FDG uptake dynamic fluctuation in tumor cells. This study investigated the feasibility of predicting tumor voxel DRM during the early treatment weeks using the advanced deep learning (DL) technique.

MATERIALS/METHODS

Serial FDG-PET/CT images were acquired at the pretreatment (pre-Tx), the 2nd and 4th treatment weeks during standard chemo-radiotherapy (35 × 2 Gy) from each of the 50 patients with head and neck squamous cell carcinomas (HNSCC). The reference value of tumor voxel DRM (DRMref), representing the average metabolic change ratio during the treatment, was determined using a linear regression performed on the standard uptake values (SUV)s obtained at the pre-Tx (SUV0), the 2nd (SUV2) and the 4th (SUV4) treatment weeks following deformable PET/CT image registration. A DL model, 3D residual-Unet with a total of 3.4 million parameters, was trained to predict the tumor voxel DRMref with using the SUV0 and SUV2 matrices as inputs. The performance of the DL model was evaluated using 10-fold cross-validation and was compared to that of a linear regression (LR) model determined on the SUV0 and SUV2 matrices.

RESULTS

The mean (SD) of the tumor voxel DRMref was 0.46 (0.2) over all 34612 tumor voxels. The predicted tumor voxel DRM was 0.5 (0.38) and 0.46 (0.15) for the LR model and the DL model, respectively. For those resistant voxels (23.7% of all tumor voxels) with a DRMref > 0.6, the DRM deviation was 0.13 (0.4) and -0.11 (0.13) for the LR model and the DL model, respectively. For those sensitive voxels (76.3%) with a DRMref ≤ 0.6, the DRM deviation was 0.01 (0.23) and 0.03 (0.08) for the LR model and the DL model, respectively.

CONCLUSION

The proposed DL model can predict the tumor voxel DRM with a single FDG-PET feedback image acquired during the 2nd treatment week of radiotherapy for HNSCC patients. The prediction accuracy was improved compared to that of the LR model with a substantial reduction in the variances of the prediction errors. This work demonstrates the great potential of utilizing DL techniques to improve the efficiency of tumor response assessment and adaptive treatment management.

[Mechanism of intestinal injury induced by WNT2B high-expressed fibroblasts in Crohn's disease]

Objective: To explore the mechanism of intestinal tissue damage induced by macrophages activated by WNT2B high-expressed fibroblasts. Methods: This study involved biological information analysis, pathological tissue research and cell experimental research. The biological information of the colon tissue from the children with inflammatory bowel disease in previous study was analyzed again with single-cell sequencing. The pathological tissues were collected by colonoscopy from 10 children with Crohn's disease treated in the Department of Gastroenterology of Guangzhou Women and Children's Medical Center from July 2022 to September 2022. According to the findings of colonoscopy, tissues with obvious inflammation or ulceration were classified as the inflammatory group, while tissues with slight inflammation and no ulceration were classified as the non-inflammatory group. HE staining was performed to observe the pathological changes of the colon tissues. Macrophage infiltration and CXCL12 expression were detected by immunofluorescence. In terms of cell experiments, fibroblasts transfected with WNT2B plasmid or empty plasmid were co-cultured with salinomycin treated or non-treated macrophages, respectively; the expression of proteins through Wnt classical pathway were detected by western blotting. Macrophages treated with SKL2001 were used as the experimental group, and those with phosphate buffer as the control group. The expression and secretion of CXCL12 in macrophages were detected by quantitative Real-time PCR and enzyme-linked immunosorbent assay (ELISA). T-test or rank sum test were used for the comparison between groups. Results: Single-cell sequencing analysis suggested that macrophages were the main cells in inflammatory bowel disease colon tissue, and there was interaction between WNT2B high-expressed fibroblasts and macrophages. HE staining of the 10 patients ((9.3±3.8) years old, 7 males and 3 females) showed that the pathological score of colon tissue in the inflammatory group was higher than that in the non-inflammatory group (4 (3, 4) vs. 2 (1, 2) points, Z=3.05, P=0.002). Tissue immunofluorescence indicated that the number of infiltrating macrophages in the inflammatory group was significantly higher than that in the non-inflammatory group under high power field of view (72.8±10.4 vs.8.4±3.5, t=25.10, P<0.001), as well as the number of cells expressing CXCL12 (14.0±3.5 vs. 4.7±1.9, t=14.68, P<0.001). In cell experiments, western blotting suggested an elevated level of glycogen synthase kinase-3β phosphorylation in macrophages co-cultured with fibroblast transfected with WNT2B plasmid, and salinmycin could reverse this change. Real-time PCR suggested that the transcription level of CXCL12 in the experimental group was higher than that in the control group (6.42±0.04 vs. 1.00±0.03, t=183.00, P<0.001), as well as the expression and secretion of CXCL12 by ELISA ((465±34) vs. (77±9) ng/L, t=13.21, P=0.006). Conclusion: WNT2B high-expressed fibroblasts can secrete WNT2B protein and activate the Wnt classical signaling pathway thus enhancing the expression and secretion of CXCL12 in macrophages, inducing the development of intestinal inflammation of Crohn's disease.

[Efficacy and safety of endoscopic diaphragm incision in children with congenital duodenal diaphragm]

Objective: To explore the efficacy and safety of endoscopic diaphragm incision in pediatric congenital duodenal diaphragm. Methods: Eight children with duodenal diaphragm treated by endoscopic diaphragm incision in the Department of Gastroenterology of Guangzhou Women and Children's Medical Center from October 2019 to May 2022 were enrolled in this study. Their clinical data including general conditions, clinical manifestations, laboratory and imaging examinations, endoscopic procedures and outcomes were retrospectively analyzed. Results: Among the 8 children, 4 were males and 4 females. The diagnosis was confirmed at the age of 6-20 months; the age of onset was 0-12 months and the course of disease was 6-18 months. The main clinical manifestations were recurrent non-biliary vomiting, abdominal distension and malnutrition. One case complicated with refractory hyponatremia was first diagnosed with atypical congenital adrenal hyperplasia in the endocrinology department. After treatment with hydrocortisone, the blood sodium returned to normal, but vomiting was recurrent. One patient underwent laparoscopic rhomboid duodenal anastomosis in another hospital but had recurred vomiting after the operation, who was diagnosed with double duodenal diaphragm under endoscope. No other malformations were found in all the 8 cases. The duodenal diaphragm was located in the descending part of the duodenum, and the duodenal papilla was located below the diaphragm in all the 8 cases. Three cases had the diaphragm dilated by balloon to explore the diaphragm opening range before diaphragm incision; the other 5 had diaphragm incision performed after probing the diaphragm opening with guide wire. All the 8 cases were successfully treated by endoscopic incision of duodenal diaphragm, with the operation time of 12-30 minutes. There were no complications such as intestinal perforation, active bleeding or duodenal papilla injury. At one month of follow-up, their weight increased by 0.4-1.5 kg, with an increase of 5%-20%. Within the postoperative follow-up period of 2-20 months, all the 8 children had duodenal obstruction relieved, without vomiting or abdominal distension, and all resumed normal feeding. Gastroscopy reviewed at 2-3 months after the operation in 3 cases found no deformation of the duodenal bulbar cavity, and the mucosa of the incision was smooth, with a duodenal diameter of 6-7 mm. Conclusion: Endoscopic diaphragm incision is safe, effective and less invasive in pediatric congenital duodenal diaphragm, with favorable clinical applicability.

[Analysis of solitary rectal ulcer syndrome in 7 children]

Objective: To analyze the clinical features, treatment and prognosis of solitary rectal ulcer syndrome (SRUS) in children. Methods: The clinical data of 7 children who were diagnosed with SRUS in Department of Gastroenterology in Guangzhou Women and Children' Medical Center from January 2019 to December 2021 were retrospectively analyzed. The clinical data including general demographics, clinical presentations, endoscopic and histologic features, treatment and outcome were extracted from hospital medical records. Results: The 7 patients were all males, and the age of onset was 6-12 years. The course before diagnosis was 2-36 months. The most common symptom was rectal bleeding (6 cases) and most common findings at initial colonoscopy were ulcer in 3 cases and protuberance in 4 cases, both located only in rectum. The intestinal histopathology of 5 cases showed characteristic fibromuscular obliteration of lamina propria. Five children were treated with mesalamine granules or suppositories, and 2 cases underwent local excision. The follow-up lasted for 5-24 months and found symptoms relieved in 5 cases, improved in 1 case, and no remission in 1 case. Colonoscopy after the treatment was performed in 5 children, among whom 2 cases achieved mucosal healing. Conclusions: SRUS in children is mainly presented with rectal bleeding, and has characteristic histological change of ulcer and protuberance in endoscopy. Pathology is crucial for diagnosis and differential diagnosis. Both the medical and surgical treatment are effective for SRUS.

DNA Barcode Technology and Its Application Prospects in Forensic Medicine

Abstract

Traditional species identification has gone through five stages -- morphology, cytology, biochemistry, immunology and molecular biology. At present, the use of DNA technology for species identification has become a research hotspot. In the use of DNA for species identification, the presentation and application of DNA barcode is of epoch-making significance. With the successful application of new technology in species identification, forensic species identification has also made corresponding development, and is expected to play an important role in forensic related fields. This paper briefly describes the general situation and principles of DNA barcode technology as well as its advantages and limitations when applied to biological classification, and discusses the future significance and feasibility of DNA barcode technology in forensic applications, in order to provide new ideas for future forensic identification.

TIM-1 Promotes Japanese Encephalitis Virus Entry and Infection

Japanese encephalitis virus (JEV) is a mosquito-borne Flavivirus, the leading cause of viral-induced encephalitis. Several host molecules have been identified as the JEV attachment factor; however, the molecules involved in JEV entry remain poorly understood. In the present study, we demonstrate that TIM-1 is important for efficient infection by JEV. Firstly, three TIM-1 variants (V1, V2, and V3) were cloned from A549 cells, and we revealed that only ectopically TIM-1 V2 expression in 293T cells significantly promotes JEV attachment, entry and infection. Point mutation of phosphatidylserine (Ptdser) binding pocket in the TIM-1 IgV domain dampened JEV entry, indicating that TIM-1-mediated JEV infection is Ptdser-dependent. Furthermore, we found the cytoplasmic domain of TIM-1 is also required for enhancing JEV entry. Additionally, knock down of TIM-1 expression in A549 cells impaired JEV entry and infection, but not attachment, suggesting that additional factors exist in A549 cells that allow the virus to bind. In conclusion, our findings demonstrate that TIM-1 promotes JEV infection as an entry cofactor, and the polymorphism of TIM-1 is associated with JEV susceptibility to host cells.

Associations of health literacy with diabetic foot outcomes: a systematic review and meta-analysis

BACKGROUND

People with diabetes have low health literacy, but the role of the latter in diabetic foot disease is unclear.

AIM

To determine, through a systematic review and meta-analysis, if health literacy is associated with diabetic foot disease, its risk factors, or foot care.

METHODS

We searched PubMed, EMBASE, CINAHL, Web of Science, Scopus and Science Direct. All studies were screened and data extracted by two independent reviewers. Studies in English with valid and reliable measures of health literacy and published tests of association were included. Data were extracted on the associations between the outcomes and health literacy. Meta-analyses were performed using random effects models.

RESULTS

Sixteen articles were included in the systematic review, with 11 in the meta-analysis. In people with inadequate health literacy, the odds of having diabetic foot disease were twice those in people with adequate health literacy, but this was not statistically significant [odds ratio 1.99 (95% CI 0.83, 4.78); two studies in 1278 participants]. There was no statistically significant difference in health literacy levels between people with and without peripheral neuropathy [standardized mean difference -0.14 (95% CI -0.47, 0.18); two studies in 399 participants]. There was no association between health literacy and foot care [correlation coefficient 0.01 (95% CI -0.07, 0.10); seven studies in 1033 participants].

CONCLUSIONS

There were insufficient data to exclude associations between health literacy and diabetic foot disease and its risk factors, but health literacy appears unlikely to have a role in foot care. The contribution of low health literacy to diabetic foot disease requires definitive assessment through robust longitudinal studies.

How deep is the inflammation in chronic rhinosinusitis? Sinus wall thickness and blood eosinophilia

Various factors have been proposed to be related to refractory chronic rhinosinusitis (CRS). Treatment for refractory CRS is challenging for ear, nose, and throat (ENT) surgeons. The aim of the study was to determine the clinical features associated with the severity of CRS that may necessitate revision surgery by eliminating the bias of the surgeons technique using standardizing surgical procedures. Sinus wall thickness and blood eosinophilia, which may represent the depth of inflammation in CRS, are associated with the need for revision surgery. We found that, when the thickness of the postero-lateral maxillary sinus wall is more than 3.03 mm, there is an increased probability for a need for revision surgery. CRS patients with thickened sinus walls were found to have poorer outcomes. Further research is needed in order to justify this type of surgical procedure for CRS.

Effect of salinity on medium- and low-pressure UV disinfection of Vibrio cholerae

The problem of biological invasions attributed to ballast water release is an ongoing problem that threatens ecosystems and human health. Ultraviolet (UV) radiation has been increasingly used for ballast water treatment mainly due to the advantages of short contact time and minimized harmful disinfection by products. In this study, the impact of salinity on the inactivation of Vibrio cholerae (NCTC 7253) was examined, and comparison of inactivation level and disinfection kinetics after medium-pressure (MP) (1 kW) and low-pressure (LP) (10 W) UV irradiation was made. MP UV exposure resulted in higher inactivation efficacy against V. cholerae than LP UV exposure especially at lower UV doses (≤3 mJ cm^-2) and salinity had a negative impact on both MP and LP UV disinfection, especially at higher UV doses (≥3 mJ cm^-2 for MP and ≥4 mJ cm^-2 for LP). To understand the mechanisms of salinity effect on V. cholerae, the enzyme-linked immunosorbent assay (ELISA) was employed to determine the number of cyclobutane pyrimidine dimers (CPDs), one major type of DNA damage. No significant effects of salinity were found at the CPDs level except for 3% artificial seawater after LP UV exposure case. It is imperative that site-specific conditions of salinity be taken into account in the design of UV reactors to treat V. cholerae and other species.

Kernohan-Woltman Notch Phenomenon Caused by Acute Traumatic Subdural Haematoma

A 27-year-old man suffered from right hemiparesis after a closed head injury. Computed tomography (CT) revealed a right hemisphere subdural haematoma with midline structure shifted to the left. The CT finding was believed to be mislabeled because the site of haematoma did not correlate with an ipsilateral hemiparesis. Magnetic resonance imaging revealed a right transtentorial uncal herniation and a small lesion within left cerebral peduncle, suggesting Kernohan-Woltman notch phenomenon (KWNP). KWNP has been rarely seen in patients with acute traumatic subdural haemorrhage. Anatomical small maximum tentorial notch width is the possible anatomical factor predisposing our patient to this phenomenon. (Hong Kong j.emerg.med. 2014;21:116-119)

Identification of a novel porcine OASL variant exhibiting antiviral activity

2', 5'-Oligoadenylate synthetase-lilke (OASL) protein is an atypical oligoadenylate synthetase (OAS) family member, which possesses antiviral activity but lacks 2', 5'-oligoadenylate synthetase activity. Here, a novel variant of porcine OASL (pOASL2) was identified through RT-PCR amplification. This gene is distinguishable from the previously described wild-type porcine OASL (pOASL1). The gene appears to be derived from a truncation of exon 4 plus 8 nucleotides of exon 5 with a premature termination, measuring only 633 bp in length, although its position corresponds to that of pOASL1. Given this novel gene appears to be a variant of pOASL, we assayed for antiviral activity of the protein. We demonstrated that pOASL2 could inhibit Japanese encephalitis virus (JEV) proliferation as well as pOASL1 in a transient overexpression assay of pOASL1 and pOASL2 in PK-15 and Vero cells. In addition to JEV, pOASL1 and pOASL2 also decreased the proliferations of Porcine reproductive and respiratory syndrome virus (PRRSV) and vesicular stomatitis virus (VSV), but did not exhibit antiviral activity against pseudorabies virus (PRV). Structural analysis showed that the pOASL2 gene retained only the first three exons at the 5'-. To investigate the role of the αN4 helix in pOASL in antiviral responses like that in hOASL, we mutated key residues in the anchor domain of the αN4 helix in pOASL2, based on the domain's location in hOASL. However, the antiviral activity of pOASL2 was not affected. Thus, the αN4 helix of pOASL likely does not play a significant role in its antiviral activity. In conclusion, pOASL2 acts as a new splice isoform of pOASL that plays a role in resistance to infection of several kinds of RNA viruses.

Cloaking through cancellation of diffusive wave scattering

A new cloaking mechanism, which makes enclosed objects invisible to diffusive photon density waves, is proposed. First, diffusive scattering from a basic core-shell geometry, which represents the cloaked structure, is studied. The conditions of scattering cancellation in a quasi-static scattering regime are derived. These allow for tailoring the diffusivity constant of the shell enclosing the object so that the fields scattered from the shell and the object cancel each other. This means that the photon flow outside the cloak behaves as if the cloaked object were not present. Diffusive light invisibility may have potential applications in hiding hot spots in infrared thermography or tissue imaging.

Isolation and genome characterization of a novel duck Tembusu virus with a 74 nucleotide insertion in the 3' non-translated region

During investigations into the outbreak of duck Tembusu virus (DTMUV) infection in 2011 in China, a DTMUV strain (DTMUV-AH2011) was isolated from the affected ducks. The length of the genome of the DTMUV-AH2011 strain was found to be 11,064 nucleotides and to possess 10,278 nucleotides of one open reading frame (ORF), flanked by 94 nucleotides of the 5' non-translated region (NTR) and 692 nucleotides of the 3' NTR. In comparison with five fully sequenced TMUV genomes, the genome of DTMUV-AH2011 had a 74 nucleotide insertion in the 3' NTR. Comparison of the DTMUV-AH2011 fully deduced amino acid sequences with those of other Tembusu virus strains reported recently in China showed they had a highly conserved polyprotein precursor, sharing 98.9% amino acid identities, at least. The overall divergences of amino acid substitutions were randomly distributed among viral proteins except for the protein NS4B, the protein NS4B was unchanged. Knowledge of the biological characters of DTMUV and the potential role of the insertion in the 3' NTR in RNA replication will be useful for further studies of the mechanisms of virus replication and pathogenesis.

Porcine Mx1 fused to HIV Tat protein transduction domain (PTD) inhibits classical swine fever virus infection in vitro and in vivo

Background

Classical swine fever (CSF) caused by CSF virus (CSFV) is highly contagious andcauses significant economic losses in the pig industry throughout the world. Previously we demonstrated that porcine Mx1 (poMx1), when fused to HIV Tat protein transduction domain (PTD), inhibits CSFV propagation in PK-15 cells, but it is unknown whether PTD-poMx1 exhibits antiviral activity in other porcine lines and it is efficacious for controlling CSFV infection in pigs in China.

Methods

Two porcine cell lines, ST and 3D4/21, were used to investigate in vitro antiviral activity of PTD-poMx1 against CSFV using confocal microscopy, western blot, flow cytometry, and real-time RT-PCR. Furthermore, in vivo antiviral activity of PTD-poMx1 was assessed by means of rectal temperature, clinical score, pathological lesion, white blood cell count, viral load, etc.

Results

PTD-poMx1 entered both cell lines within 3 h and maintained for 16 h, but did not affect CSFV binding and uptake. Viral titers and qRT-PCR data showed that PTD-poMx1 inhibited CSFV replication in both cell lines, showing significant antiviral activity after infection. Injection of PTD-poMx1 into CSFV-challenged pigs attenuated CSFV symptoms and viremia in dose-dependent manner but did not completely block virus replication within 14 days post challenge, suggesting that PTD-poMx1 confers partial protection against a lethal challenge.

Conclusion

We demonstrated the anti-CSFV activity of PTD-poMx1 in vitro and in vivo. The results have shown that treatment with PTD-poMx1 alleviated symptoms and viral load in infected pigs. The results support our previous in vitro studies and suggest that PTD-poMx1 could be promising in reducing the clinical signs caused by CSFV.

The A66G back mutation in NS2A of JEV SA14-14-2 strain contributes to production of NS1' protein and the secreted NS1' can be used for diagnostic biomarker for virulent virus infection

Japanese encephalitis virus (JEV) is the most common cause of the prevalent encephalitis in Asia-Pacific region and poses a serious risk to public health. Here, we developed a reliable reverse genetics system based on the JEV SA14-14-2 strain to further explore the mechanism for the synthesis of NS1' protein and to investigate the function of NS1' protein during virus infection. NS1' is an additional form of NS1 protein with 52 amino acid carboxy-terminal extension and is expressed by the members of the Japanese encephalitis (JE) serogroup due to the translation frameshift. A66G substitution in NS2A gene of JEV SA14-14-2 strain contributed to recover the GC-rich pseudoknot and resulted in the formation of the NS1'. The NS1' protein has no significant effect on the virus replication properties in BHK-21 cells. Animal experiments demonstrated that the NS1' protein had a rather minor effect on neurovirulence of JEV SA14-14-2 strain. But the NS1'-expressing virus (rA66G) could induce a higher humoral immune response than the NS1'-non-expressing virus (rSA14-14-2). NS1' protein can be detected in the serum of JEV rA66G infected animal and in the cultural media of that infected mammalian cells. Interesting, only the dimer of NS1' can be detected in the cultural media of the infected BHK-21 cells and the amount of the secreted NS1' was in agreement with that of the secreted virion. In comparison with the live-attenuated JE vaccine strain which is incapable of formation of NS1', most of the virulent JEV strains produce the NS1' protein. And the secreted NS1' may serve as an early surrogate biomarker for viremia to distinguish the field infection from the vaccine inoculation. In total, in the present study, we identified the nt 66 in the viral NS2A gene as one of the critical site for the -1 programmed ribosomal frameshift to produce the NS1' protein and demonstrated the secreted NS1' could be used for diagnostic biomarker during JEV infection.

[Hsp70 Fused with the Envelope Glycoprotein E0 of Classical Swine Fever Virus Enhances Immune Responses in Balb/c Mice]

Heat-shock protein (Hsp) 70 potentiates specific immune responses to some antigenic peptides fused to it. Here, the prokaryotic plasmids harboring the envelope glycoprotein E0 gene of classical swine fever virus (CSFV) and/or the Hsp70 gene of Haemophilus parasuis were constructed and expressed in Escherichia coli Rosseta 2(R2). The fusion proteins were then purified. Groups of Balb/c mice were immunized with these fusion proteins, respectively, and sera collected 7 days after the third immunization. Immune effects were determined via an enzyme-linked immunosorbent assay and flow cytometric analyses. E0-Hsp70 fusion protein and E0+Hsp70 mixture significantly improved the titer of E-specific antibody, levels of CD4+ and CD8+ T cells, and release of interferon-γ. These findings suggested that Hsp70 can significantly enhance the immune effects of the envelope glycoprotein E0 of CSFV, thereby laying the foundation of further application in pigs.

[Expression and adjuvant effects of the fusion peptide TBP5]

Thymopentin (TP5) and bursopentin (BP5) are both immunopotentiators. To explore whether the TP5-BP5 fusion peptide (TBP5) has adjuvant activity or not, we cloned the TBP5 gene and confirmed that the TBP5 gene in a recombinant prokaryotic expression plasmid was successfully expressed in Escherichia coli BL21. TBP5 significantly promoted the proliferation of thymic and splenic lymphocytes of mice. The potential adjuvant activity of the TBP5 was examined in mice by coinjecting TBP5 and H9N2 avian influenza virus (AIV) inactivated vaccine. HI antibody titers, HA antibodies and cytokines levels (IL-4 and IFN-γ) were determined. We found that TBP5 markedly elevated serum HI titers and HA antibody levels, induced the secretion of both IL-4 and IFN-γ cytokines. Furthermore, virus challenge experiments confirmed that TBP5 contributed to inhibition replication of the virus [H9N2 AIV (A/chicken/Jiangsu/NJ07/05)] from mouse lungs. Altogether, these findings suggest that TBP5 may be an effective adjuvant for avian vaccine and that this study provides a reference for further research on new vaccine adjuvants.

[Antitumor mechanism of Bursopentin (BP5)]

OBJECTIVE

Bursopentin (BP5) is a multi-functional bioactive peptide with functions of immunomodulatory, antioxidant and antitumor. However, the antitumor mechanism of BP5 is still unclear.

METHODS

We constructed T7 phage cDNA library of DT40 cells, and the proteins interacted with BP5 were identified. Then, the expression profile of BP5-treated DT40 cells were analyzed using gene microarray, p53 Luciferase activity was detected.

RESULTS

The results of the expression profiling revealed that BP5 regulated expression of 1078 genes, of which 537 were up-regulated and 541 were down-regulated. Differentially expressed genes involved in various pathways were identified, of which 25 pathways were associated with immune responses and tumorigenic processes, including the p53 signaling. Furththmore, BP5 significantly enhanced p53 luciferase activity and stimulated expression of p53 protein in HCT116 cells.

CONCLUSION

These results suggest that BP5 exerted antitumor activity through p53 signaling and that this study provides novel insights on the antitumor mechanism of BP5.

[Enhancement of mouse immune response by recombinant adenovirus co-expressing VP1-2A of foot-and-mouth disease virus and porcine IFN-α]

OBJECTIVE

To construct the recombinant adenovirus co-expressing foot-and-mouth disease virus (FMDV) viral structural protein1-2A (VP1-2A) and porcine interferon-α (poIFN-α), and study its impact on mouse adaptive immune responses.

METHODS

FMDV VP1-2A genes and porcine IFN-α (poIFN-α) genes were successively cloned into pAdeno Vator-CMV5-IRES-GFP, and then both pAdeno Vator-CMV5-IRES-GFP with VP1-2A-poIFN-α and pAdeno Vator ΔE1/E3 were co-transfected into E.coli BJ5183 competent cells. The homologous recombinant plasmid rAd5VP1-2A-poIFN-α was screened and linearized by Pac I to expose the encapsidation signal and then transfected into HEK293A cells by Lipofectamine(TM)2000. The positive recombinant viruses were named rAd5VP1-2A-poIFN-α. The BALB/c mice were immunized by the recombinant adenovirus rAd5VP1-2A-poIFN-α or rAd5VP1 (adenoviral vectors solely expressing FMDV VP1) or blank adenovirus as control (Ad virus). The FMDV VP1-specific IgG, IgG1, IgG2a and cytokines IL-4, IFN-γ were determined by the ELISA, and the index of peripheral blood lymphocyte proliferation was detected by MTT assay.

RESULTS

The recombinant adenovirus co-expressing FMDV VP1-2A and porcine IFN-α (rAd5VP1-2A-poIFN-α) was successfully constructed. ELISA and MTT assay showed that compared with rAd5VP1 group, rAd5VP1-2A-poIFN-α could enhance the secretion of FMDV VP1-specific IgG, IgG1 and IgG2a, promote the secretion of IL-4 and IFN-γ, and increase the index of peripheral blood lymphocyte proliferation.

CONCLUSION

The rAd5VP1-2A-poIFN-α could significantly improve the mouse adaptive immune responses.

An unexpected route for otolaryngology bacterial contamination with a Venturi atomizer

BACKGROUND

The Venturi-principle atomizer is a commonly used device in otolaryngology practices. The purpose of this study is to evaluate the possible route of bacterial contamination from the nasal vestibule to the atomizer tip through the jet airflow created during the use of the Venturi atomizer.

METHODS

Thirty nostrils from 15 enrolled volunteers were tested. The aerosols generated by spraying sterilized saline into the nostrils were collected using a specially made aerosol-collecting nozzle cap. The collected samples were sent for bacterial culture, and nasal vestibular swab cultures were performed for comparison.

RESULTS

In the aerosol-exposed group, 18 out of 30 samples (60%) were positive for bacterial growth, confirming the bacterial contamination from the nasal vestibule to the atomizer tip through the reverse jet airflow. The bacteria species in 8 of the 18 positive samples were identical to those from the nasal swab culture results from the same nostril.

CONCLUSION

In ordinary otolaryngology practices, there are significant risks for bacterial contamination from the nasal vestibule to the tip of the Venturi atomizer even without direct contact. Clinicians must be more aware of this pattern of contamination, which has not been reported in the existing literature.

Lentivirus-mediated RNA interference against Japanese encephalitis virus infection in vitro and in vivo

Japanese encephalitis virus, a serious mosquito-borne flavivirus, causes acute encephalitis in humans and many animals, with a high fatality rate. RNA interference is a reasonable antiviral mechanism for target gene silencing. In this study, four lentiviral shRNAs (LV-E1, LV-E2, LV-NS3 and LV-NS4b) were constructed. The results showed that four recombinant lentiviruses suppressed JEV replication in vitro. Through treatment with LV-E1 or LV-E2, the TCID50 values were reduced by 10(3)-fold during 120h post-challenge; the relative expression of viral mRNA was <7% or 13% in mouse and human neuroblastoma cells. Lentiviral shRNAs displayed robust inhibitory activity in various cells and against different genotypes of JEV. In vivo, pre-treatments of LV-E1 or LV-E2 resulted in no viral particles being observed in suckling mice brain sections. For 21days of observation, 100% of mice were protected against lethal JEV injection by two pre-treatments with LV-E1 or LV-E2; the survival of the mice pre-challenged with lethal JEV was 88.3%/66.7% by treatment with LV-E1 or LV-E2. LV-E1 and LV-E2 suppressed the induction of inflammatory mediators effectively in neuroblastoma cells and mice. Lentiviral shRNAs significantly inhibit JEV infection for long-term in vitro and in vivo and effectively reduce the inflammatory response and relieve encephalitis symptoms, highlighting the feasibility of using lentivirus-mediated RNAi for potential therapy in JEV infection.

In vitro inhibition of the replication of classical swine fever virus by porcine Mx1 protein

Classical swine fever virus (CSFV) is the causative pathogen of classical swine fever (CSF), a highly contagious disease of swine. Mx proteins are interferon-induced dynamin-like GTPases present in all vertebrates with a wide range of antiviral activities. Although Zhao et al. (2011) have reported that human MxA can inhibit CSFV replication, whether porcine Mx1 (poMx1) has anti-CSFV activity remains unknown. In this study, we generated a cell line designated PK-15/EGFP-poMx1 which expressed porcine Mx1 protein constitutively, and we observed that the proliferation of progeny virus in this cell line was significantly inhibited as measured by virus titration, indirect immune fluorescence assay, Q-PCR and Western blot. Furthermore, when PTD-poMx1 fusion protein expressed in Escherichia coli (Zhang et al., 2013) was used to treat CSFV-infected PK-15 cells, the results showed that PTD-poMx1 inhibited CSFV replication in a dose-dependent manner. Additionally, the proliferation of progeny virus was inhibited as measured by virus titration and Q-PCR. Overall, the results demonstrated that poMx1 effectively inhibited CSFV replication, suggesting that poMx1 may be a valuable therapeutic agent against CSFV infection.

Expression of 4kD scorpion defensin and its in vitro synergistic activity with conventional antibiotics

The 4kD scorpion defensin (SD) is a potent disulfide-linked peptide. In this study, we expressed it in methylotrophic yeast Pichia pastoris and purified it using Ni-NTA His Bind Resin. We investigated its in vitro antibacterial activity and effect in combination with several conventional antibiotics. We first examined its antibacterial activity towards several Gram-positive and Gram-negative bacteria. Then we used the broth microdilution method to test drugs alone and in combination and used the fractional inhibitory concentration (FIC index) to classify the drug interactions. Our study showed the expressed SD peptide has antibacterial activity against Salmonella typhimurium, E. coli and S. aureus etc. Synergy or additive interaction was observed between SD and Norfloxacin, Polymyxin B and Ampicillin. Cell growth tests showed that combination of SD and Norfloxacin can improve their activity against bacteria. This result maybe permit lower using of the conventional antibiotic agents more effectively and safely.

The potential mechanism of Bursal-derived BPP-II on the antibody production and avian pre-B cell

The bursa of Fabricius is critical for the normal development of the B lymphocytes responsible for antibody production. However, the mechanism of the bursal-derived bioactive factor on B cell development is little reported. In this paper, chicks were immunized with BPP-II and AIV vaccine or AIV antigen, and antibody and IL-4 production were detected. The results showed that BPP-II played strongly inducing roles on the humoral immune responses. To investigate the gene expression at transcriptional level, avian pre-B lymphocyte DT40 cells were treated with BPP-II, and were analyzed with the gene microarray. The results proved that BPP-II treatment regulated 11 pathways, in which homologous recombination is a vital mechanism which is involved in antibody Ig gene conversion and diversification during B cell development. These results suggested Bursal-derived biological active factor BPP-II might be involved in the antibody production processes and B cell development, which is vital to the humoral central immune organ, the bursa of Fabricius.

Multiple linear epitopes (B-cell, CTL and Th) of JEV expressed in recombinant MVA as multiple epitope vaccine induces a protective immune response

Epitope-based vaccination might play an important role in the protective immunity against Japanese encephalitis virus (JEV) infection. The purpose of the study is to evaluate the immune characteristics of recombinant MVA carrying multi-epitope gene of JEV (rMVA-mep). The synthetic gene containing critical epitopes (B-cell, CTL and Th) of JEV was cloned into the eukaryotic expression vector pGEM-K1L, and the rMVA-mep was prepared. BALB/c mice were immunized with different dosages of purified rMVA-mep and the immune responses were determined in the form of protective response against JEV, antibodies titers (IgG1 and IgG2a), spleen cell lymphocyte proliferation, and the levels of interferon-γ and interleukin-4 cytokines. The results showed that live rMVA-mep elicited strongly immune responses in dose-dependent manner, and the highest level of immune responses was observed from the groups immunized with 10⁷ TCID₅₀ rMVA-mep among the experimental three concentrations. There were almost no difference of cytokines and neutralizing antibody titers among 10⁷ TCID₅₀ rMVA-mep, recombinant ED3 and inactivated JEV vaccine. It was noteworthy that rMVA-mep vaccination potentiates the Th1 and Th2-type immune responses in dose-dependent manner, and was sufficient to protect the mice survival against lethal JEV challenge. These findings demonstrated that rMVA-mep can produce adequate humoral and cellular immune responses, and protection in mice, which suggested that rMVA-mep might be an attractive candidate vaccine for preventing JEV infection.

Antiviral activity of phage display selected peptides against Porcine reproductive and respiratory syndrome virus in vitro

Porcine reproductive and respiratory syndrome is an important infectious disease of pigs and has a significant harmful effect on the livestock industry, especially in China. PRRSV ORF1b gene encodes primary proteins which play a vital role during PRRSV replication. In this paper, various 12-amino-acid peptides were displayed. These peptides could bind to the polymerase and helicase of PRRSV ORF1b protein, respectively, in which p9 exerted the highest antiviral activity with an IC50 of 56 μM, and the minimum toxicity to cells. It was proved that p9 inhibited PRRSV replication in infected MARC-145 cells in a dose-dependent manner, and the amino acid sequence of HRILMRIR was important for antiviral activity of p9. Also, p9 could bind to the cell membrane and penetrated into cells. These result suggested that p9 might be a potential therapeutic drug for PRRSV infection.

The suppressive effects of Bursopentine (BP5) on oxidative stress and NF-ĸB activation in lipopolysaccharide-activated murine peritoneal macrophages

BACKGROUND/AIM

Bursopentine (BP5) is a novel thiol-containing pentapeptide isolated from chicken bursa of Fabricius, and is reported to exert immunomodulatory effects on B and T lymphocytes. It has been found that some thiol compounds, such as glutathione (GSH) and N-acetylcysteine (NAC) protect living cells from oxidative stress. This led us to investigate whether BP5 had any ability to protect macrophages from oxidative stress as well as any mechanism that might underlie this process.

METHODS

Murine peritoneal macrophages activated by lipopolysaccharide (LPS) (2 μg/ml) were treated with single bouts (0, 25, 50, and 100 μM) of BP5.

RESULTS

BP5 potently suppressed the markers for oxidative stress, including nitric oxide (NO), reactive oxygen species (ROS), lipid peroxidation, and protein oxidation. It also decreased the expression and activity of inducible nitric oxide synthase (iNOS) and promoted a protective antioxidant state by elevating GSH content and by activating the expression and activity of certain key antioxidant and redox enzymes, including glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT). This suppressive effect on oxidative stress was accompanied by down-regulated expression and activity of nuclear factor kappa B (NF-κB).

CONCLUSION

These findings demonstrate that BP5 can protect LPS-activated murine peritoneal macrophages from oxidative stress. BP5 may have applications as an anti-oxidative stress reagent.

Synthesis and secretory expression of hybrid antimicrobial peptide CecA–mag and its mutants in Pichia pastoris

The hybrid peptide CA(1–7)–M(2–12) gene was designed according to the N-terminal 1–7 amino acid sequence of the antimicrobial peptide cecropin A (CA) and the N-terminal 2–12 amino acid sequence of maganin (M) and synthesized using Pichia pastoris preferred codons. The gene was cloned into pPICZ αA and transformed into the P. pastoris recipient bacterium SMD1168, regulated by the alcohol oxidase (AOX). Expression of the cecA-mag hybrid antimicrobial peptide (MW, 1.9 kDa) revealed broad-spectrum antibiotic activity and to the ability to inhibit growth of most G− and G+ bacteria. Three mutants of cecA-mag were designed and synthesized by recombination polymerase chain reaction site-directed mutagenesis to investigate the relationship between the structure and function of this antimicrobial peptide. The inhibition titers of these mutants against Staphylococcus aureus were evaluated using the agar diffusion method. Under the conditions of the same concentration and volume, the bacteriostatic diameters of three cecA-mag mutants were 1.2, 1.2 and 1.5 times, respectively, compared with the diameters of wild-type cecA-mag.

P3-13-09: Impact of Estrogen Receptor Negativity on Clinical Outcomes Following Accelerated Partial Breast Irradiation

Purpose: To determine the impact of estrogen receptor (ER) negativity on clinical outcomes for patients treated with Accelerated Partial Breast Irradiation (APBI).

Materials/Methods(s): We evaluated 506 consecutive patients treated with interstitial brachytherapy (n= 199), balloon-based brachytherapy (n=203), and 3D-CRT (n=104). ER negative (ERN) status was assigned using the traditional definition of an ER nuclear IHC stain &lt; 10%, which corresponds to an Allred/NSABP staining score of &lt; 2. 63 patients (12.5%) were ER negative and 443 (87.5%) were ER positive (ERP). Patient demographics and clinical outcomes (IBTR, RNF, DM, DFS, CSS, OS) were analyzed for each group.

Results: The two groups had similar patient characteristics. Tumor sizes were slightly larger for the ERN group at 11.9mm vs. 10.7mm, although this was not statistically significant (p=0.14). No differences were seen in median age (63 vs. 64 years, p=0.36), rate of HER-2/neu overexpression (83% vs. 91%, p=0.11), or lymph node positivity (6% vs. 9%, p=0.55) between the ERN vs. ERP groups, respectively. There were an equal distribution of invasive ductal carcinoma (ERN n=55, 87%; ERP n=387, 87%) and DCIS (ERN n=8, 13%; ERP n=56, 13%) patients within each group. The use of chemotherapy (55% vs. 15%, p&lt;0.001) and nuclear grade (71% vs. 12%, p&lt;0.001) were higher in the ERN vs. ERP cohort. With a mean follow up of 6.1 years, the 5-year actuarial rates of ipsilateral breast tumor recurrence (IBTR), regional nodal failure (RNF), and distant metastasis (DM) for the entire cohort were 1.8%, 0.6%, and 3.2%. Although this was not statistically significant, ERN patients appear to have an increased rate of local failure than patients with ERP histology (4.0% vs. 1.5%, p=0.13). Rates of RNF and DM were, however, significantly higher for the ERN group (RNF: 4.9% ERN vs. 0% ERP, p&lt;0.001; DM: 12.1% ERN vs. 2.0% ERP, p&lt;0.001). Although there was no difference in overall survival at six years (86% vs. 90%, p=0.67), we observed a shorter disease-free survival (86.4% vs. 96.5%, p= 0.01) and cause-specific survival (90% vs. 98%, p=0.01) for the ERN vs. ERP groups.

Conclusion: The ER negative phenotype of early-stage breast cancer may have a decreased rate of locoregional control. We observed a higher rate of DM with reduced disease-free and cause-specific survival in ER negative cases, emphasizing the importance of systemic therapy and careful, long-term follow up for these patients. Prospective study of this histologic subtype with a larger cohort of patients is needed to substantiate these findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-13-09.

Role of lipid rafts in porcine reproductive and respiratory syndrome virus infection in MARC-145 cells

Lipid rafts play an important role in the life cycle of many viruses. Cholesterol is a critical structural component of lipid rafts. Although the porcine reproductive and respiratory syndrome virus (PRRSV) has restricted cell tropism for cells of the monocyte/macrophage lineage, a non-macrophage cell MARC-145 was susceptible to PRRSV because of the expression of virus receptor CD163 on the cell surface, therefore MARC-145 cells is used as model cell for PRRSV studies. In order to determine if cholesterol is involved in PRRSV infection in MARC-145 cells, we used three pharmacological agents: methyl-β cyclodextrin (MβCD), mevinolin, and filipin complex to deplete cholesterol in MARC-145. Although these agents act by different mechanisms, they all significantly inhibited PRRSV infection. The inhibition could be prevented by addition of exogenous cholesterol. Cell membrane cholesterol depletion after virus infection had no effect on PRRSV production and cholesterol depletion pre-infection did not reduce the virus attachment, suggesting cholesterol is involved in virus entry. Further results showed that cholesterol depletion did not change expression levels of the PRRSV receptor CD163 in MARC-145, had no effect on clathrin-mediated endocytosis, but disturbed lipid-raft-dependent endocytosis. Collectively, these studies suggest that cholesterol is critical for PRRSV entry, which is likely to be mediated by a lipid-raft-dependent pathway.

Bursopentine as a novel immunoadjuvant enhances both humoral and cell-mediated immune responses to inactivated H9N2 Avian Influenza virus in chickens

There is an urgent need for identification of a new adjuvant capable of selectively promoting an efficient immune response for use with vaccines and especially subunit vaccines. Our pervious study showed that Bursopentine (BP5) is a novel immunomodulatory peptide and has the ability to significantly stimulate an antigen-specific immune response in mice. In this study, the potential adjuvant activities of BP5 were examined in chickens by coinjection of BP5 and an inactivated avian influenza virus (AIV) (A/Duck/Jiangsu/NJ08/05 [AIV H9N2 subtype]). The results suggested that BP5 markedly elevated serum hemagglutination inhibition (HI) titers and antigen-specific antihemagglutinin (anti-HA) antibody (IgG) levels, induced both Th1 (interleukin 2 [IL-2] and gamma interferon [IFN-γ])- and Th2 (IL-4)-type cytokines, promoted the proliferation of peripheral blood lymphocytes, and increased populations of CD3(+) T cells and their subsets CD4(+) (CD3(+) CD4(+)) T cells and CD8(+) (CD3(+) CD8(+)) T cells. Furthermore, a virus challenge experiment revealed that BP5 contributes to protection against homologous avian influenza virus challenge by reducing viral replication in chicken lungs. This study indicates that the combination of inactivated AIVs and BP5 gives a strong immune response at both the humoral and cellular levels and implies that BP5 is a novel immunoadjuvant suitable for vaccine design.

Axo-axonal interaction in autonomic regulation of the cerebral circulation

Noradrenaline (NE) and acetylcholine (ACh) released from the sympathetic and parasympathetic neurones in cerebral blood vessels were suggested initially to be the respective vasoconstricting and dilating transmitters. Both substances, however, are extremely weak post-synaptic transmitters. Compelling evidence indicates that nitric oxide (NO) which is co-released with ACh from same parasympathetic nerves is the major transmitter for cerebral vasodilation, and its release is inhibited by ACh. NE released from the sympathetic nerve, acting on presynaptic β2-adrenoceptors located on the neighbouring parasympathetic nitrergic nerves, however, facilitates NO release with enhanced vasodilation. This axo-axonal interaction mediating NE transmission is supported by close apposition between sympathetic and parasympathetic nerve terminals, and has been shown in vivo at the base of the brain and the cortical cerebral circulation. This result reveals the physiological need for increased regional cerebral blood flow in 'fight-or-flight response' during acute stress. Furthermore, α7- and α3β2-nicotinic ACh receptors (nAChRs) on sympathetic nerve terminals mediate release of NE, leading to cerebral nitrergic vasodilation. α7-nAChR-mediated but not α3β2-nAChR-mediated cerebral nitrergic vasodilation is blocked by β-amyloid peptides (Aβs). This may provide an explanation for cerebral hypoperfusion seen in patients with Alzheimer's disease. α7- and α3β2-nAChR-mediated nitrergic vasodilation is blocked by cholinesterase inhibitors (ChEIs) which are widely used for treating Alzheimer's disease, leading to possible cerebral hypoperfusion. This may contribute to the limitation of clinical use of ChEIs. ChEI blockade of nAChR-mediated dilation like that by Aβs is prevented by statins pretreatment, suggesting that efficacy of ChEIs may be improved by concurrent use of statins.

[A novel double expression shuttle vector to get marker-free recombinant modified vaccinia virus Ankara]

A novel double expression shuttle vector named pLR-gpt was constructed for marker-free recombinant modified vaccinia virus Ankara generation. A delectable Eco gpt marker was adopted with Cre/LoxP DNA recombination system and a BHK-21 cell line that can express Cre enzyme. Eco gpt gene controlled by P7.5 promoter from Vaccinia virus was cloned between two LoxP sites in the same direction. Additionally, two multiple cloning site under control of other two Vaccinia virus promoters were constructed outside LoxP sites. With this new transfer vector, Eco gpt marker in rMVA can be deleted on BHK-Cre with interaction between Cre enzyme and LoxP sequence. In order to verify the efficacy of this system, ORF5 and ORF6 gene of Porcine reproductive and respiratory syndrome virus (PRRSV) NJ-a strain were cloned into two multiple cloning sites of pLR-gpt to construct recombinant plasmid pLR-ORFS/ORF6. Homologous recombination between pLR-ORF5/ORF6 and wtMVA on BHK-21 cell was mediated by liposome by infecting cells with 0.01 MOI wtMVA two hours before transfection. After twelve cycles of selection, recombinant MVA with selecting marker Eco gpt was obtained and named as rMVAgpt-GP5/M. By infecting BHK-Cre, the Eco gpt marker in rMVAgpt-GP5/M was deleted and this rMVA was named as rMVA-GP5/M. Expression of GP5 and M protein was identified with Western blotting and IFA. Results from PCR and biological study for rMVA indicated that Eco gpt marker was completely deleted.

CONCLUSIONS

double expression transfer vector for marker-free recombinant Modified vaccinia virus Ankara generation was successfully constructed, and works well in MVA expression system.