Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the domi...Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the dominant epidemic strain in China. We developed an attenuated aMPV subtype B strain by serial passaging in Vero cells and evaluated its safety and efficacy as a vaccine candidate. The safety test showed that after the 30th passage, the LN16-A strain was fully attenuated, as clinical signs of infection and histological lesions were absent after inoculation.The LN16-A strain did not revert to a virulent strain after five serial passages in chickens. The genomic sequence of LN16-A differed from that of the parent wild-type LN16(wtLN16) strain and had nine amino acid mutations. In chickens, a single immunization with LN16-A induced robust humoral and cellular immune responses, including the abundant production of neutralizing antibodies, CD4^(+) T lymphocytes, and the Th1(IFN-γ) and Th2(IL-4 and IL-6)cytokines. We also confirmed that LN16-A provided 100% protection against subtype B aMPV and significantly reduced viral shedding and turbinate inflammation. Our findings suggest that the LN16-A strain is a promising live attenuated vaccine candidate that can prevent infection with subtype B aMPV.展开更多
The nest environment may limit the ability of nest-bound birds to hear sounds from the outside world.In vocal learning species,such as humans and songbirds,it is vital for young animals to hear the voices of conspecif...The nest environment may limit the ability of nest-bound birds to hear sounds from the outside world.In vocal learning species,such as humans and songbirds,it is vital for young animals to hear the voices of conspecific animals early in life.In songbirds,nest structure varies considerably across species,and the resulting impact on sound transmission may have consequences for vocal learning in nestlings.In this study,we tested the hypothesis that the nest environment attenuates song of Savannah Sparrows(Passerculus sandwichensis),grassland songbirds that build nests on the ground under cover of dense vegetation.We recorded live Savannah Sparrows singing at variable distances from 21 nests.We recorded songs using one microphone inside the nest(the typical position of a nestling)and another placed 1 m directly above the nest(a typical position of an adult).We found a substantial reduction in signal-to-noise ratio,where songs recorded inside the nest were an average of 11 dB lower than songs recorded directly above the nest.We estimate that the attenuation imposed by the nest reduced the maximum acoustic environment from 117.7 m(for recordings above the nest),to 78.6 m(for recordings within the nest),which is analogous to listening from a position 39.1 m farther away from the singer.Previous research estimated that song transmits up to 100 m in this species,so any adult male within 100 m of a young bird was previously considered a potential vocal tutor.By reducing the nestling acoustic environment from 100 m to 78.6 m,the number of male tutors available to nestlings is reduced by an average of 27%.Given the growing evidence that song learning begins very early in life,future research on vocal development should account for how the structural properties of the natal environment affect the songs that nestlings hear.展开更多
[Objective] The study aimed to obtain attenuated strain of Haemophilus parasuis.[Method] Tn5 transposon technology was used to construct a library of mutants.Positive mutants were screened by kanamycin resistance.Fals...[Objective] The study aimed to obtain attenuated strain of Haemophilus parasuis.[Method] Tn5 transposon technology was used to construct a library of mutants.Positive mutants were screened by kanamycin resistance.False positive was identified by PCR and then removed.Mice were infected to detect the virulence of mutants.The bionomics of attenuated strains were detected,too.[Result] The attenuated mutants showed similar reproductive activity to that of wild strain.The virulence of mutants was still stable after 30 passages.[Conclusion] This study provided foundation for exploring the virulence factors and pathogenic mechanism of HPS.展开更多
Attenuated adenomatous polyposis(AAP) is a poorly understood syndrome, that can be defined as the presence of 10-99 synchronous adenomas in the large bowel, and it is considered a phenotypic variant of familial adenom...Attenuated adenomatous polyposis(AAP) is a poorly understood syndrome, that can be defined as the presence of 10-99 synchronous adenomas in the large bowel, and it is considered a phenotypic variant of familial adenomatous polyposis(FAP). This definition has the advantage of simplicity, but it may include sporadic multiple adenomas of the large bowel at an extreme, or FAP cases on the other side. AAP shows a milder phenotype than FAP, with an older age of onset of adenomas and cancer, and less frequent extracolonic manifestations. AAP may be diagnosed as a single case in a family or, less frequently, it may be present in other family members, and it shows distinct pattern of inheritance. In less than 50% of cases, it may be caused by adenomatous polyposis coli(APC) or MUTYH mutations, referred to as APC-associated polyposis, inherited as an autosomal dominant trait, or MUTYH-associated polyposis, which shows an autosomal recessive mechanism of inheritance, respectively. Surveillance should rely on colonoscopy at regular intervals, with removal of adenomas and careful histological examination. When removal of polyps is not possible or advanced lesions are observed, the surgical approach is mandatory, being subtotal colectomy with ileo-rectal anastomosis the treatment of choice. Studies on this syndrome are lacking, and controversies are still present on many issues, thus, other clinical and genetic studies are requested.展开更多
In this article, we study reconstruction of nonuniform attenuated SPECT data and present analytic reconstruction formulae which are similar to Novikov＇s inversion formula. Furthermore, we extend Natterer＇s results.
Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation...Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1（HIF-1）.Hypoxia interferes degradation of HIF-1 alpha subunit（HIF-1α）, leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit（HIF-1β） and subsequent activation of HIF-1 pathway. Apical periodontitis（periapical lesion） is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine（DMOG） and adenovirusinduced constitutively active HIF-1α（CA-HIF1 A）. Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B（NF-κB） and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.展开更多
Neuroinflammation is recognized as an important pathogenic factor for aging and related cognitive disorders. Mitogen-activated protein kinase and nuclear factor kappa B signaling pathways may mediate neuroinflammation...Neuroinflammation is recognized as an important pathogenic factor for aging and related cognitive disorders. Mitogen-activated protein kinase and nuclear factor kappa B signaling pathways may mediate neuroinflammation. Saponins from Panax japonicus are the most abundant and bioactive members in rhizomes of Panaxjaponicus, and show anti-inflammatory activity. However, it is not known whether saponin from Panaxjaponicus has an anti-inflammatory effect in the aging brain, and likewise its underlying mechanisms. Sprague-Dawley rats were divided into control groups （3-, 9-, 15-, and 24-month-old groups） and saponins from Panaxjaponicus-treated groups. Saponins from Panaxjaponicus-treated groups were orally administrated saponins from Panaxjaponicus at three doses of 10, 30, and 60 mg/kg once daily for 6 months until the rats were 24 months old. Immunohistochemical staining and western blot assay results demonstrated that many microglia were activated in 24-month-old rats compared with 3- and 9-month-old rats. Expression of interleukin-1β, tumor necrosis factor-a, cyclooxygenase-2, and inducible nitric oxide synthase increased. Each dose of saponins from Panaxjaponicus visibly suppressed microglial activation in the aging rat brain, and inhibited expression levels of the above factors. Each dose of saponins from Panax japonicus markedly diminished levels of nuclear factor kappa B, IKBa, extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. These results confirm that saponins from Panaxjaponicus can mitigate neuroinflammation in the aging rat brain by inhibition of the mito- gen-activated protein kinase and nuclear factor kappa B signaling pathways.展开更多
To investigate the immune responses to the attenuated Mycoplasma hyopneumoniae 168 strain vaccine, 8-15 d old piglets were immunized with M. hyopneurnoniae 168 strain vaccine by intrapulmonic route. And the specific I...To investigate the immune responses to the attenuated Mycoplasma hyopneumoniae 168 strain vaccine, 8-15 d old piglets were immunized with M. hyopneurnoniae 168 strain vaccine by intrapulmonic route. And the specific IgG antibody in serum, lymphoproliferation, IFNT, and specific secretory IgA （SIgA） antibody in bronchoalveolar lavage fluid were detected on 30 and 60 d post-immunization （DPI）, respectively. On 60 DPI, all the pigs except for those in health control group were challenged with a field M. hyopneumoniae strain JS. Necropsy was performed on 30 d post-challenge （DPC）. The results showed that IFN7 and specific SIgA were stimulated on surface of respiratory tract after immunization. And peripheral blood mononuclear cells could also be proliferated about 1.81 and 2.12 fold on 30 and 60 DPI when stimulated by M. hyopneumoniae protein in vitro. However, no serum IgG antibody against M. hyopneumoniae was detected during the whole immune phage. After challenge, vaccinated pigs were observed with only very slight histological lesion in individual lobes. None of vaccinated pigs showed any clinical signs. While the unvaccinated pigs from challenge control group showed varying degrees of clinical sign and severe macroscopical lesion of mycoplasmal pneumonia of swine （MPS）. The result suggested that the attenuated M. hyopneumoniae 168 strain vaccine inoculated by intrapulmonic route could activate the systemic cellular immunity, the local mucosal immunity and IFNγ secretion in respiratory tract to against M. hyopneumoniae infection in piglets.展开更多
Objective To prepare the live recombinant vaccine of attenuated Salmonella typhimurium SL3261 expressing Helicobacterpylori （H. pylori） B subunit （UreB） and to determine whether it could be used as an oral vaccine...Objective To prepare the live recombinant vaccine of attenuated Salmonella typhimurium SL3261 expressing Helicobacterpylori （H. pylori） B subunit （UreB） and to determine whether it could be used as an oral vaccine against H. pylori infection. Methods Using genomic DNA of H. pylori Sydney strain （SS1） as template, the H. pylori UreB gene fragment was amplified by PCR and subcloned into the expression vector pTC01. The recombinant plasmid pTC01-UreB was then transferred into LBS000 to obtain modified forms, and further conversed into the attenuated Salmonella typhimurium SL3261 to obtain recombinant SL3261/pCT01-UreB as an oral immunization reagent, which was then used to orally immunize Balb/c mice twice at a three-week interval. Twelve weeks later, anti-UreB IgA antibodies in intestinal fluid and IgG antibodies in sera were determined by ELISA. The relating data in control groups （including body weight, gastric inflammation, etc.） were also collected. Results The sequencing analysis showed that the UreB gene fragment amplified by PCR was consistent with the sequence of the H. pylori UreB gene. The restriction enzyme digestion revealed that the correct pTC01-UreB was obtained. SDS-PAGE and Western blot showed that a 61KD protein was expressed in SL3261/pTC01-UreB, which could be recognized by anti-H, pylori UreB antiserum and was absent in the control containing only Salmonella typhimurium SL3261 strain. The multiple oral immunization with SL3261/pTC01-UreB could significantly induce H. pylori specific mucosal IgA response as well as serum IgG responses. IFN-T and IL-10 levels were significantly increased in SL3261/pTC01-UreB group, and no obvious side effect and change in gastric inflammation were observed. Conclusion The attenuated vaccine of Salmonella typhimurium expressing H. pylori UreB can be used as an oral vaccine against H. pylori infection.展开更多
AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1...AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1-3 primary school children were inoculated with 1 dose (10(6.5) TCID(50)) of H2 strain vaccines in a nonrandomized, controlled trial conducted in Fucheng County, Hebei Province in May 1997.Another 6485 children in the same grades and compatible in gender and age were enrolled as controls. Epidemiological and serological survey was conducted to evaluate the protective efficacy of the vaccines. ELISA was used to detect serum IgM anti-HAV.RESULTS:HA outbreak started in early May 1998, peaked in the middle of the same month, and lasted about 80 days. Overall 302 HA cases were found, 192(63.58%) were 5-9 years old. One vaccinee and 25 control cases were found to have hepatitis A, which account for 0.28% (1/356) and 5.92% (25/422) of all vaccinees and controls in the 14 villages, respectively. The protective efficacy of vaccines was 95.27% (95% CI: 85.83%-104.72%). In subjects tested for anti-HAV IgM from 13 villages, 1(0.40%) overt and 11(4.06%) asymptomatic HAV cases were found in 271 vaccinees but 21(6.69%) of overt and asymptomatic ones were found in 314 controls.CONCLUSION:H2 strain vaccines were excellent in preventing overt hepatitis A,but not so effective in preventing asymptomatic hepatitis A virus infection.A booster dose might be needed to get permanent reliable immunity.展开更多
In this work, the image reconstruction in π-scheme short-scan single-photon emission computed tomography （SPECT） with nonuniform attenuation is derived in its most general form when π-scheme short-scan SPECT entai...In this work, the image reconstruction in π-scheme short-scan single-photon emission computed tomography （SPECT） with nonuniform attenuation is derived in its most general form when π-scheme short-scan SPECT entails data acquisition over disjoint angular intervals without conjugate views totaling to π radians. The reconstruction results are based on decomposition of Novikov＇s inversion operator into three parts bounded in the L2 sense. The first part involves the measured partial data; the second part is a skew-symmetric operator; the third part is a symmetric and compact contribution. It is showed firstly that the operators involved belong to L（L^2（B）. Furthermore numerical simulations are conducted to demonstrate the effectiveness of the developed method.展开更多
Objective:To develop allenualed slrains of Salmonella enterica serorar Typhi(S.typhi) for the candidate vaccine by osmolar stress.Mothods:S.typhi SS3 and SS5 strains were isolated from asymptomatic typhoid carriers in...Objective:To develop allenualed slrains of Salmonella enterica serorar Typhi(S.typhi) for the candidate vaccine by osmolar stress.Mothods:S.typhi SS3 and SS5 strains were isolated from asymptomatic typhoid carriers in Mamakkal,Tamil Nadu.India.Both strains were grown in LB(Luria Bertani) medium supplemented with various concentration of NaCl(0.1- 0.7M) respectively.The effecl of osmolar stress was determined at molecular level by PCR using MCR 06 and MCR07 primers corresponding to ompR with chromosomal DNA of S.typhi SS3 and SS5 strains.Attenuation by osmolar stress results in deletion mutation of the.S.typhi slrains was determined by agglutination assays,precipitation method.SDS PAGE analysis and by animal models.Results:The 799 bp amplified ompR gene product from wild type S.typhi SS3 and SS5 illustrate the presence of virulent gene.Interestingly,there was only a 282 bp amplified product from S.typhi SS3 and SS5 grown in the presence of 0.5.0.6 and 0.7 M NaCl.This illustrates the occurrence of deletion mutation in ompR gene al high concentration of NaCl.Furthermore,both the wildtype and mutant S.typhi outer membrane SDS-PAGF.profile reveals the differences in the expression of ompF.ompC and ompA proteins.In mice,wild type and mutant strains lethal dose(LD_(50)) were determined.The mice died within 72 h when both the wild type strains were injected intraperitoneally with 3 log CFU-mL^(-1).When the mice were injected with the mutants in same dosage,no clinical symptoms were observed;whereas the serum antibodv litre was elicited within two weeks indicated that the mutants have the ability to induce protective humoral immune response.These results suggest that S.typhi SS3 and SS5 may bo used as good candidate strains for the development of live attenuated vaccine against salmonellosis.Conclusions:This study demonstrates that the S.typhi strains were allenualed and could be good vaccine candidates in future.展开更多
Bone is known to have a natural function to heal itself.However,if the bone damage is beyond a critical degree,intervention such as bone grafting may be imperative.In this work,the fabrication of a novel bone scaffold...Bone is known to have a natural function to heal itself.However,if the bone damage is beyond a critical degree,intervention such as bone grafting may be imperative.In this work,the fabrication of a novel bone scaffold composed of natural bone components and polycaprolactone(PCL)using 3D printing is put forward.α1,3-galactosyltransferase deficient pigs were used as the donor source of a xenograft.Decellularized porcine bone(DCB)with attenuated immunogenicity was used as the natural component of the scaffold with the aim to promote bone regeneration.The 3D printed DCB-PCL scaffolds combined essential advantages such as uniformity of the interconnected macropores and high porosity and enhanced compressive strength.The biological properties of the DCB-PCL scaffolds were evaluated by studying cell adhesion,viability,alkaline phosphatase activity and osteogenic gene expression of human bone marrow-derived mesenchymal stem cells.The in vitro results demonstrated that the DCB-PCL scaffolds exhibit an enhanced performance in promoting bone differentiation,which is correlated to the DCB content.Furthermore,critical-sized cranial rat defects were used to assess the effect of DCB-PCL scaffolds on bone regeneration in vivo.The results confirm that in comparison with PCL scaffolds,the DCB-PCL scaffolds can significantly improve new bone formation in cranial defects.Thus,the proposed 3D printed DCB-PCL scaffolds emerge as a promising regeneration alternative in the clinical treatment of large bone defects.展开更多
Streptococcus equi ssp. zooepidemicus(SEZ) is a pathogen associated with a wild range of animal species. Frequent outbreaks have occurred in recent years in pigs, horses, goats and dogs which is liable to infect human...Streptococcus equi ssp. zooepidemicus(SEZ) is a pathogen associated with a wild range of animal species. Frequent outbreaks have occurred in recent years in pigs, horses, goats and dogs which is liable to infect humans. There is a lack of efficient vaccines against this disease and the occurrence of antibiotic resistance may render drug therapies ineffective. In this study, gene deletion mutant(ΔSEZ) in pathogenicity islands SeseCisland_4 was constructed. The mutant ΔSEZ had a 52-fold decrease in 50% lethal dose(LD_(50)) and had less capacity to adhere epithelial cells. Importantly, immunization of mice with attenuated vaccine ΔSEZ at the dose of 10~2 colony-forming units(CFU) mL^(–1) elicited a significant humoral antibody response, with an antibody titer of 1:12 800. Therefore, 10~2 CFU mL^(–1) might be used as the appropriate immune dose for the attenuated vaccine ΔSEZ, which provided mice with efficient protection against virulent SEZ. In addition, the hyperimmune sera against 10~2 CFU m L–1 attenuated vaccine ΔSEZ could confer significant protection against virulent SEZ infection in the passive immunization experiment and exhibited efficient bactericidal activity in the whole blood assay. Meanwhile, no viable bacteria was detected in blood when mice were immunized with ΔSEZ at the dose of 10~2 CFU mL^(–1) via hypodermic injection. Thereafter, the mutant ΔSEZ at the dose of 10~2 CFU mL^(–1) could confer significant protection in mice and had less negative effects on host, which could be an effective attenuated vaccine candidate for the prevention of SEZ.展开更多
Duck hepatitis B virus(DHBV) shares many basic characteristics with hepatitis B virus(HBV) and is an attractive model for vaccine development. In this study, DHBV DNA vaccines were designed to express envelope and cap...Duck hepatitis B virus(DHBV) shares many basic characteristics with hepatitis B virus(HBV) and is an attractive model for vaccine development. In this study, DHBV DNA vaccines were designed to express envelope and capsid fusion proteins to enhance the breadth of immune response in ducks. Attenuated Salmonella typhimurium(SL7207) was used as a carrier and adjuvant to boost the magnitude of immune response. Based on this strategy, novel DNA vaccines(SL7207-p VAX1-LC and SL7207-p VAX1-SC) were generated. Growth kinetics, genetic stabilities and relative transcription levels of the L, S and C genes introduced by these vaccine strains were measured before inoculation to guarantee safety and efficacy. The relative transcript levels of the CD4 and CD8 T genes and the antibody levels(Ig Y) in ducks receiving the vaccines were higher than those in single gene delivered groups. Additionally, the copy number of covalently closed circular DNA in hepatocytes after DHBV challenge also provided evidence that our fusion vaccines could enhance the protective efficiency against DHBV infection in ducks.展开更多
The dispersion relations of normal modes in the layered constructions are studied. In the frequency region with negative permittivity, we investigate the normal modes near the air-metal and the air-matematerial interf...The dispersion relations of normal modes in the layered constructions are studied. In the frequency region with negative permittivity, we investigate the normal modes near the air-metal and the air-matematerial interfaces and compare them. An extra bulk mode appearing in a pass band of two media is found near the air-matematerial interface, which is different from the air-metal case. Moreover, the bulk mode will be further proved by the attenuated total reflection （ATR） technique, in which the coupling between the incident electromagnetic waves and the normal modes is studied. For p-polarized incident waves, the ATR spectra based on the Otto and the Kretschmann configurations are obtained numerically, where the dips present the excitations of the surface and bulk modes. Furthermore, we also discuss the influences of the middle layer thickness, the incident angle and the damping term on the reflection in detail. It is found that the coupling frequencies and the maximum strength are strongly dependent on the above media parameters.展开更多
Listeria monocytogenes(LM),a Gram-positive facultative intracellular bacterium,can be used as an effective exogenous antigen expression vector in tumor-target therapy.But for successful clinical application,it is nece...Listeria monocytogenes(LM),a Gram-positive facultative intracellular bacterium,can be used as an effective exogenous antigen expression vector in tumor-target therapy.But for successful clinical application,it is necessary to construct attenuated LM stain that is safe yet retains the potency of LM based on the full virulent pathogen.In this study,attenuated LM and recombinants of LM expressing melanoma inhibitory activity(MIA) were constructed successfully.The median lethal dose(LD 50) and invasion efficiency of attenuated LM strains were detected.The recombinants were utilized for immunotherapy of animal model of B16F10 melanoma.The level of MIA mRNA expression in tumor tissue was detected by using real-time polymerase chain reaction(PCR) with specific sequence,meanwhile the anti-tumor immune response was assayed by flow cytometric analysis and enzyme-linked immunosorbent spot(ELISPOT) assay.The results showed the toxicity and invasiveness of attenuated LM were decreased as compared with LM,and attenuated LM expressing MIA,especially the double-genes attenuated LM recombinant,could significantly induce anti-tumor immune response and inhibit tumor growth.This study implicates attenuated LM may be a safer and more effective vector for immunotherapy of melanoma.展开更多
Effects of attenuated highly pathogenic pig reproductive and respiratory syndrome（HP-PRRS）TJM-F92 strain vaccine on immune antibody level against classical swine fever（CSF）and foot-and-mouth disease（FMD）were stu...Effects of attenuated highly pathogenic pig reproductive and respiratory syndrome（HP-PRRS）TJM-F92 strain vaccine on immune antibody level against classical swine fever（CSF）and foot-and-mouth disease（FMD）were studied from October 8 to November 12 in 2014,in order to optimize vaccination program of CSF,HP-PRRS and FMD and to provide scientific guidance for animal disease control and prevention work.The results showed that attenuated HP-PRRS（TJMF92 strain）vaccine had no significant effect on immune antibody level of hog cholera lapinized virus（HCLV,ST passage cell vaccine）attenuated vaccine and FMD-O inactivated vaccines（OZK/93 strain）,and single or combined use of three vaccines received good immunization effects.展开更多
Osteoarthritis(OA)is an inflammatory disease involving the joints that is prevalent in the global aging population.The purpose of this study is to determine whether irisin can attenuate osteoarthritis(OA)progression i...Osteoarthritis(OA)is an inflammatory disease involving the joints that is prevalent in the global aging population.The purpose of this study is to determine whether irisin can attenuate osteoarthritis(OA)progression in anterior cruciate ligament transection(ACLT)mice models and the mechanism of irisin therapy effect on OA by increase the resistance of apoptosis in MLO-Y4 cells induced by mechanical stretch in vitro.Methods For in vivo study,3-month-old male C57BL/6 J mice were randomized to three groups,sham-operated,anterior cruciate ligament transection(ACLT)-operated treated with vehicle,and ACLT-operated treated with irisin by intraperitoneal injection once a week.Cartilage erosion was observed by HE staining.Osteoarthritis Research Society International(OARSI)scores were evaluated according to the safranin O stai-ning.The microstructure of tibia cortical bone,trabecular bone,and subchondral bone was analyzed by micro-CT and the bone histomorphometry has been administrated including mineral apposition rate(MAR).Edu staining and cck-8 were used for the detection of the proliferation of MLO-Y4 cells.For mechanical stress,cells were seeded on the collagen-I coated chamber subjected with a peak biaxial stretch of 20%at 1 Hz for 16 hours to induce apoptosis.Flow cytometry was used for the detection of apoptosis and cell cycle.TUNNEL was used for staining the apoptotic cells and rt-PCR was applied for quantifying the expression of mRNA such as Bax,Bcl-2,SOST,c-myc,Opg.Western blot was utilized to confirm the mechanism of how irisin decrease the osteocyte apoptosis.Results In vivo,irisin can attenuate articular cartilage degeneration.Irisin maintains the proportion of hyaline cartilage and calcified cartilage and keep fewer cartilage erosions in ACLT-operated mice.For immunohistochemical(IHC)staining,irisin reduced the expression of caspase3,Bax and matrix metalloproteinase-13 in both cartilage and subchondral bone.Irisin-treated ACLT group shows higher Trabecular number(Tb.N)and bone volume fraction(BV/TV)compared to the vehicle-treated ACLT group.In vitro, irisin significantly increased the proliferation of MLO-Y4 cells detected by Edu and Ki67 staining,and irisin can protect the cells from both mechanical stretchinduced apoptosis detected by FITC-PI flow cytometry and maintain the cell activity by regulating the expression of Bax,Bcl-2,and c-myc.Transcriptome sequencing shows that irisin significantly activates the MAPK signaling pathway and we confirm the result by western blot:irisin effectively activates the Erk signaling pathway through phosphorylation and has a certain activation effect on p38 signaling pathway,no activation was observed for FAK signaling pathway.Conclusions Irisin can attenuate the progression of OA by decrease the apoptosis of osteocyte,which can improve the microarchitecture of subchondral bone.Erk pathway activation plays an important role in reducing the apoptosis of osteocyte.展开更多
Objective: Cancer vaccines that rely on tumor antigen-specific CD8^+ T cell responses, are promising anti-cancer adjuvant immunotherapies. This study investigated whether genetically attenuated Plasmodium sporozoite(G...Objective: Cancer vaccines that rely on tumor antigen-specific CD8^+ T cell responses, are promising anti-cancer adjuvant immunotherapies. This study investigated whether genetically attenuated Plasmodium sporozoite(GAS) could be used as a novel vector to induce antigen-specific CD8^+ T cell responses against lung cancer.Methods: We constructed GAS/MAGE-A3, a recombinant GAS engineered to express the lung cancer-specific antigen, melanomaassociated antigen 3(MAGE-A3), and assessed its therapeutic effects against lung cancer.Results: Robust parasite-specific CD8αlow CD11ahigh and CD49dhigh CD11ahigh CD4^+ T cell responses as well as a MAGE-A3-specific CD8^+ T cell response were induced in GAS/MAGE-A3-immunized mice. Adoptive transfer of GAS/MAGE-A3-induced CD8^+ T cells from HLA-A2 transgenic mice into lung cancer-bearing nude mice inhibited tumor growth and prolonged survival.Conclusions: These findings demonstrate that GAS/MAGE-A3 induces a strong MAGE-A3-specific CD8^+ T cell response against lung cancer in vivo, and indicate that GAS is a novel and efficacious antigen delivery vector for antitumor immunotherapy.展开更多
基金supported by the National Key Research and Development Program of China (2022YFD1800604)the China Agricultural Research System (CARS-41)the Heilongjiang Touyan Innovation Team Program of China
文摘Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the dominant epidemic strain in China. We developed an attenuated aMPV subtype B strain by serial passaging in Vero cells and evaluated its safety and efficacy as a vaccine candidate. The safety test showed that after the 30th passage, the LN16-A strain was fully attenuated, as clinical signs of infection and histological lesions were absent after inoculation.The LN16-A strain did not revert to a virulent strain after five serial passages in chickens. The genomic sequence of LN16-A differed from that of the parent wild-type LN16(wtLN16) strain and had nine amino acid mutations. In chickens, a single immunization with LN16-A induced robust humoral and cellular immune responses, including the abundant production of neutralizing antibodies, CD4^(+) T lymphocytes, and the Th1(IFN-γ) and Th2(IL-4 and IL-6)cytokines. We also confirmed that LN16-A provided 100% protection against subtype B aMPV and significantly reduced viral shedding and turbinate inflammation. Our findings suggest that the LN16-A strain is a promising live attenuated vaccine candidate that can prevent infection with subtype B aMPV.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)for financial support through grants to D.J.M., D.R.N.,and A.E.M.N.the Animal Behaviour Society+1 种基金the American Ornithological Societythe Society of Canadian Ornithologists for research grants to S.L.D.
文摘The nest environment may limit the ability of nest-bound birds to hear sounds from the outside world.In vocal learning species,such as humans and songbirds,it is vital for young animals to hear the voices of conspecific animals early in life.In songbirds,nest structure varies considerably across species,and the resulting impact on sound transmission may have consequences for vocal learning in nestlings.In this study,we tested the hypothesis that the nest environment attenuates song of Savannah Sparrows(Passerculus sandwichensis),grassland songbirds that build nests on the ground under cover of dense vegetation.We recorded live Savannah Sparrows singing at variable distances from 21 nests.We recorded songs using one microphone inside the nest(the typical position of a nestling)and another placed 1 m directly above the nest(a typical position of an adult).We found a substantial reduction in signal-to-noise ratio,where songs recorded inside the nest were an average of 11 dB lower than songs recorded directly above the nest.We estimate that the attenuation imposed by the nest reduced the maximum acoustic environment from 117.7 m(for recordings above the nest),to 78.6 m(for recordings within the nest),which is analogous to listening from a position 39.1 m farther away from the singer.Previous research estimated that song transmits up to 100 m in this species,so any adult male within 100 m of a young bird was previously considered a potential vocal tutor.By reducing the nestling acoustic environment from 100 m to 78.6 m,the number of male tutors available to nestlings is reduced by an average of 27%.Given the growing evidence that song learning begins very early in life,future research on vocal development should account for how the structural properties of the natal environment affect the songs that nestlings hear.
基金Supported by National High Technology Research and Development Program of China(2006AA10A206)National Natural Science Foundation of China(31001072)the Fund of Beijing Academy of Agriculture and Forestry Sciences for Young Scholars(QNJJ201012)~~
文摘[Objective] The study aimed to obtain attenuated strain of Haemophilus parasuis.[Method] Tn5 transposon technology was used to construct a library of mutants.Positive mutants were screened by kanamycin resistance.False positive was identified by PCR and then removed.Mice were infected to detect the virulence of mutants.The bionomics of attenuated strains were detected,too.[Result] The attenuated mutants showed similar reproductive activity to that of wild strain.The virulence of mutants was still stable after 30 passages.[Conclusion] This study provided foundation for exploring the virulence factors and pathogenic mechanism of HPS.
文摘Attenuated adenomatous polyposis(AAP) is a poorly understood syndrome, that can be defined as the presence of 10-99 synchronous adenomas in the large bowel, and it is considered a phenotypic variant of familial adenomatous polyposis(FAP). This definition has the advantage of simplicity, but it may include sporadic multiple adenomas of the large bowel at an extreme, or FAP cases on the other side. AAP shows a milder phenotype than FAP, with an older age of onset of adenomas and cancer, and less frequent extracolonic manifestations. AAP may be diagnosed as a single case in a family or, less frequently, it may be present in other family members, and it shows distinct pattern of inheritance. In less than 50% of cases, it may be caused by adenomatous polyposis coli(APC) or MUTYH mutations, referred to as APC-associated polyposis, inherited as an autosomal dominant trait, or MUTYH-associated polyposis, which shows an autosomal recessive mechanism of inheritance, respectively. Surveillance should rely on colonoscopy at regular intervals, with removal of adenomas and careful histological examination. When removal of polyps is not possible or advanced lesions are observed, the surgical approach is mandatory, being subtotal colectomy with ileo-rectal anastomosis the treatment of choice. Studies on this syndrome are lacking, and controversies are still present on many issues, thus, other clinical and genetic studies are requested.
基金supported by the National Natural Science Foundation of China(61271398)Natural Science Foundation of Zhejiang Province(LY14A010004)K.C.Wong Magna Fund in Ningbo University
文摘In this article, we study reconstruction of nonuniform attenuated SPECT data and present analytic reconstruction formulae which are similar to Novikov＇s inversion formula. Furthermore, we extend Natterer＇s results.
基金supported by the National Institute of Dental and Craniofacial Research(NIDCR)the National Center for Research Resources(NCRR)of the National Institutes of Health(NIH)under award numbers R21DE023178,R01DE024796,and S10RR027553
文摘Hypoxia（low oxygen level） is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1（HIF-1）.Hypoxia interferes degradation of HIF-1 alpha subunit（HIF-1α）, leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit（HIF-1β） and subsequent activation of HIF-1 pathway. Apical periodontitis（periapical lesion） is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine（DMOG） and adenovirusinduced constitutively active HIF-1α（CA-HIF1 A）. Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B（NF-κB） and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.
基金supported by the National Natural Science Foundation of China,No.81374001,81673778,81273895the Foundation for Innovative Research Groups of the Natural Science Foundation of Hubei Province of China,No.2013CFA014
文摘Neuroinflammation is recognized as an important pathogenic factor for aging and related cognitive disorders. Mitogen-activated protein kinase and nuclear factor kappa B signaling pathways may mediate neuroinflammation. Saponins from Panax japonicus are the most abundant and bioactive members in rhizomes of Panaxjaponicus, and show anti-inflammatory activity. However, it is not known whether saponin from Panaxjaponicus has an anti-inflammatory effect in the aging brain, and likewise its underlying mechanisms. Sprague-Dawley rats were divided into control groups （3-, 9-, 15-, and 24-month-old groups） and saponins from Panaxjaponicus-treated groups. Saponins from Panaxjaponicus-treated groups were orally administrated saponins from Panaxjaponicus at three doses of 10, 30, and 60 mg/kg once daily for 6 months until the rats were 24 months old. Immunohistochemical staining and western blot assay results demonstrated that many microglia were activated in 24-month-old rats compared with 3- and 9-month-old rats. Expression of interleukin-1β, tumor necrosis factor-a, cyclooxygenase-2, and inducible nitric oxide synthase increased. Each dose of saponins from Panaxjaponicus visibly suppressed microglial activation in the aging rat brain, and inhibited expression levels of the above factors. Each dose of saponins from Panax japonicus markedly diminished levels of nuclear factor kappa B, IKBa, extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. These results confirm that saponins from Panaxjaponicus can mitigate neuroinflammation in the aging rat brain by inhibition of the mito- gen-activated protein kinase and nuclear factor kappa B signaling pathways.
基金supported by the Natural Science Foundation of Jiangsu Province, China (BK2007711)the China Postdoctoral Fundation (20070421022)the Three Agricultural Projects Fundation of Jiangsu Province, China (SX2007082)
文摘To investigate the immune responses to the attenuated Mycoplasma hyopneumoniae 168 strain vaccine, 8-15 d old piglets were immunized with M. hyopneurnoniae 168 strain vaccine by intrapulmonic route. And the specific IgG antibody in serum, lymphoproliferation, IFNT, and specific secretory IgA （SIgA） antibody in bronchoalveolar lavage fluid were detected on 30 and 60 d post-immunization （DPI）, respectively. On 60 DPI, all the pigs except for those in health control group were challenged with a field M. hyopneumoniae strain JS. Necropsy was performed on 30 d post-challenge （DPC）. The results showed that IFN7 and specific SIgA were stimulated on surface of respiratory tract after immunization. And peripheral blood mononuclear cells could also be proliferated about 1.81 and 2.12 fold on 30 and 60 DPI when stimulated by M. hyopneumoniae protein in vitro. However, no serum IgG antibody against M. hyopneumoniae was detected during the whole immune phage. After challenge, vaccinated pigs were observed with only very slight histological lesion in individual lobes. None of vaccinated pigs showed any clinical signs. While the unvaccinated pigs from challenge control group showed varying degrees of clinical sign and severe macroscopical lesion of mycoplasmal pneumonia of swine （MPS）. The result suggested that the attenuated M. hyopneumoniae 168 strain vaccine inoculated by intrapulmonic route could activate the systemic cellular immunity, the local mucosal immunity and IFNγ secretion in respiratory tract to against M. hyopneumoniae infection in piglets.
基金This work was supported by Chinese Postdoctoral Fund (Grant No. 2004035426).
文摘Objective To prepare the live recombinant vaccine of attenuated Salmonella typhimurium SL3261 expressing Helicobacterpylori （H. pylori） B subunit （UreB） and to determine whether it could be used as an oral vaccine against H. pylori infection. Methods Using genomic DNA of H. pylori Sydney strain （SS1） as template, the H. pylori UreB gene fragment was amplified by PCR and subcloned into the expression vector pTC01. The recombinant plasmid pTC01-UreB was then transferred into LBS000 to obtain modified forms, and further conversed into the attenuated Salmonella typhimurium SL3261 to obtain recombinant SL3261/pCT01-UreB as an oral immunization reagent, which was then used to orally immunize Balb/c mice twice at a three-week interval. Twelve weeks later, anti-UreB IgA antibodies in intestinal fluid and IgG antibodies in sera were determined by ELISA. The relating data in control groups （including body weight, gastric inflammation, etc.） were also collected. Results The sequencing analysis showed that the UreB gene fragment amplified by PCR was consistent with the sequence of the H. pylori UreB gene. The restriction enzyme digestion revealed that the correct pTC01-UreB was obtained. SDS-PAGE and Western blot showed that a 61KD protein was expressed in SL3261/pTC01-UreB, which could be recognized by anti-H, pylori UreB antiserum and was absent in the control containing only Salmonella typhimurium SL3261 strain. The multiple oral immunization with SL3261/pTC01-UreB could significantly induce H. pylori specific mucosal IgA response as well as serum IgG responses. IFN-T and IL-10 levels were significantly increased in SL3261/pTC01-UreB group, and no obvious side effect and change in gastric inflammation were observed. Conclusion The attenuated vaccine of Salmonella typhimurium expressing H. pylori UreB can be used as an oral vaccine against H. pylori infection.
基金national ninth five-year study program for tackling key scientific problems,No.03-01-01
文摘AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1-3 primary school children were inoculated with 1 dose (10(6.5) TCID(50)) of H2 strain vaccines in a nonrandomized, controlled trial conducted in Fucheng County, Hebei Province in May 1997.Another 6485 children in the same grades and compatible in gender and age were enrolled as controls. Epidemiological and serological survey was conducted to evaluate the protective efficacy of the vaccines. ELISA was used to detect serum IgM anti-HAV.RESULTS:HA outbreak started in early May 1998, peaked in the middle of the same month, and lasted about 80 days. Overall 302 HA cases were found, 192(63.58%) were 5-9 years old. One vaccinee and 25 control cases were found to have hepatitis A, which account for 0.28% (1/356) and 5.92% (25/422) of all vaccinees and controls in the 14 villages, respectively. The protective efficacy of vaccines was 95.27% (95% CI: 85.83%-104.72%). In subjects tested for anti-HAV IgM from 13 villages, 1(0.40%) overt and 11(4.06%) asymptomatic HAV cases were found in 271 vaccinees but 21(6.69%) of overt and asymptomatic ones were found in 314 controls.CONCLUSION:H2 strain vaccines were excellent in preventing overt hepatitis A,but not so effective in preventing asymptomatic hepatitis A virus infection.A booster dose might be needed to get permanent reliable immunity.
基金supported by the National Natural Science Foundation of China(61271398)K.C.Wong Magna Fund in Ningbo University
文摘In this work, the image reconstruction in π-scheme short-scan single-photon emission computed tomography （SPECT） with nonuniform attenuation is derived in its most general form when π-scheme short-scan SPECT entails data acquisition over disjoint angular intervals without conjugate views totaling to π radians. The reconstruction results are based on decomposition of Novikov＇s inversion operator into three parts bounded in the L2 sense. The first part involves the measured partial data; the second part is a skew-symmetric operator; the third part is a symmetric and compact contribution. It is showed firstly that the operators involved belong to L（L^2（B）. Furthermore numerical simulations are conducted to demonstrate the effectiveness of the developed method.
文摘Objective:To develop allenualed slrains of Salmonella enterica serorar Typhi(S.typhi) for the candidate vaccine by osmolar stress.Mothods:S.typhi SS3 and SS5 strains were isolated from asymptomatic typhoid carriers in Mamakkal,Tamil Nadu.India.Both strains were grown in LB(Luria Bertani) medium supplemented with various concentration of NaCl(0.1- 0.7M) respectively.The effecl of osmolar stress was determined at molecular level by PCR using MCR 06 and MCR07 primers corresponding to ompR with chromosomal DNA of S.typhi SS3 and SS5 strains.Attenuation by osmolar stress results in deletion mutation of the.S.typhi slrains was determined by agglutination assays,precipitation method.SDS PAGE analysis and by animal models.Results:The 799 bp amplified ompR gene product from wild type S.typhi SS3 and SS5 illustrate the presence of virulent gene.Interestingly,there was only a 282 bp amplified product from S.typhi SS3 and SS5 grown in the presence of 0.5.0.6 and 0.7 M NaCl.This illustrates the occurrence of deletion mutation in ompR gene al high concentration of NaCl.Furthermore,both the wildtype and mutant S.typhi outer membrane SDS-PAGF.profile reveals the differences in the expression of ompF.ompC and ompA proteins.In mice,wild type and mutant strains lethal dose(LD_(50)) were determined.The mice died within 72 h when both the wild type strains were injected intraperitoneally with 3 log CFU-mL^(-1).When the mice were injected with the mutants in same dosage,no clinical symptoms were observed;whereas the serum antibodv litre was elicited within two weeks indicated that the mutants have the ability to induce protective humoral immune response.These results suggest that S.typhi SS3 and SS5 may bo used as good candidate strains for the development of live attenuated vaccine against salmonellosis.Conclusions:This study demonstrates that the S.typhi strains were allenualed and could be good vaccine candidates in future.
基金the financial support from National Natural Science Foundation of China(81601626)Zhejiang Provincial Natural Science of Foundation of China(Y20C070010)+1 种基金start-up funding from Wenzhou Institute,University of Chinese Academy of Sciences(WIUCASQD2019002)Singapore MOE Tier 1 Grant RG46/18.
文摘Bone is known to have a natural function to heal itself.However,if the bone damage is beyond a critical degree,intervention such as bone grafting may be imperative.In this work,the fabrication of a novel bone scaffold composed of natural bone components and polycaprolactone(PCL)using 3D printing is put forward.α1,3-galactosyltransferase deficient pigs were used as the donor source of a xenograft.Decellularized porcine bone(DCB)with attenuated immunogenicity was used as the natural component of the scaffold with the aim to promote bone regeneration.The 3D printed DCB-PCL scaffolds combined essential advantages such as uniformity of the interconnected macropores and high porosity and enhanced compressive strength.The biological properties of the DCB-PCL scaffolds were evaluated by studying cell adhesion,viability,alkaline phosphatase activity and osteogenic gene expression of human bone marrow-derived mesenchymal stem cells.The in vitro results demonstrated that the DCB-PCL scaffolds exhibit an enhanced performance in promoting bone differentiation,which is correlated to the DCB content.Furthermore,critical-sized cranial rat defects were used to assess the effect of DCB-PCL scaffolds on bone regeneration in vivo.The results confirm that in comparison with PCL scaffolds,the DCB-PCL scaffolds can significantly improve new bone formation in cranial defects.Thus,the proposed 3D printed DCB-PCL scaffolds emerge as a promising regeneration alternative in the clinical treatment of large bone defects.
基金was supported by the National Key R&D Program of China(2017YFD0500203)the National Natural Science Foundation of China(31672574)+3 种基金the Special Fund for Agro-scientific Research in the Public Interest,China(201403054)the Primary Research&Development Plan of Jiangsu Province,China(BE2017341)the Jiangsu Agricultural Science and Technology Innovation Fund [CX(16)1028]the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)
文摘Streptococcus equi ssp. zooepidemicus(SEZ) is a pathogen associated with a wild range of animal species. Frequent outbreaks have occurred in recent years in pigs, horses, goats and dogs which is liable to infect humans. There is a lack of efficient vaccines against this disease and the occurrence of antibiotic resistance may render drug therapies ineffective. In this study, gene deletion mutant(ΔSEZ) in pathogenicity islands SeseCisland_4 was constructed. The mutant ΔSEZ had a 52-fold decrease in 50% lethal dose(LD_(50)) and had less capacity to adhere epithelial cells. Importantly, immunization of mice with attenuated vaccine ΔSEZ at the dose of 10~2 colony-forming units(CFU) mL^(–1) elicited a significant humoral antibody response, with an antibody titer of 1:12 800. Therefore, 10~2 CFU mL^(–1) might be used as the appropriate immune dose for the attenuated vaccine ΔSEZ, which provided mice with efficient protection against virulent SEZ. In addition, the hyperimmune sera against 10~2 CFU m L–1 attenuated vaccine ΔSEZ could confer significant protection against virulent SEZ infection in the passive immunization experiment and exhibited efficient bactericidal activity in the whole blood assay. Meanwhile, no viable bacteria was detected in blood when mice were immunized with ΔSEZ at the dose of 10~2 CFU mL^(–1) via hypodermic injection. Thereafter, the mutant ΔSEZ at the dose of 10~2 CFU mL^(–1) could confer significant protection in mice and had less negative effects on host, which could be an effective attenuated vaccine candidate for the prevention of SEZ.
基金supported by the National Key Technology R&D Program of China(2015BAD12B05)the earmarked fund for China Agricultural Research System(CARS-43-8)+1 种基金the Integration and Demonstration of Key Technologies for Duck Industry in Sichuan Province,China(2014NZ0030)the Sichuan Province Research Programs,China(2014-002)
文摘Duck hepatitis B virus(DHBV) shares many basic characteristics with hepatitis B virus(HBV) and is an attractive model for vaccine development. In this study, DHBV DNA vaccines were designed to express envelope and capsid fusion proteins to enhance the breadth of immune response in ducks. Attenuated Salmonella typhimurium(SL7207) was used as a carrier and adjuvant to boost the magnitude of immune response. Based on this strategy, novel DNA vaccines(SL7207-p VAX1-LC and SL7207-p VAX1-SC) were generated. Growth kinetics, genetic stabilities and relative transcription levels of the L, S and C genes introduced by these vaccine strains were measured before inoculation to guarantee safety and efficacy. The relative transcript levels of the CD4 and CD8 T genes and the antibody levels(Ig Y) in ducks receiving the vaccines were higher than those in single gene delivered groups. Additionally, the copy number of covalently closed circular DNA in hepatocytes after DHBV challenge also provided evidence that our fusion vaccines could enhance the protective efficiency against DHBV infection in ducks.
基金Project supported by the National Natural Science Foundation of China(Grant No.10775055)
文摘The dispersion relations of normal modes in the layered constructions are studied. In the frequency region with negative permittivity, we investigate the normal modes near the air-metal and the air-matematerial interfaces and compare them. An extra bulk mode appearing in a pass band of two media is found near the air-matematerial interface, which is different from the air-metal case. Moreover, the bulk mode will be further proved by the attenuated total reflection （ATR） technique, in which the coupling between the incident electromagnetic waves and the normal modes is studied. For p-polarized incident waves, the ATR spectra based on the Otto and the Kretschmann configurations are obtained numerically, where the dips present the excitations of the surface and bulk modes. Furthermore, we also discuss the influences of the middle layer thickness, the incident angle and the damping term on the reflection in detail. It is found that the coupling frequencies and the maximum strength are strongly dependent on the above media parameters.
基金supported by grants from the National Natural Science Foundation of China (No. 30600535 and No.30901288)
文摘Listeria monocytogenes(LM),a Gram-positive facultative intracellular bacterium,can be used as an effective exogenous antigen expression vector in tumor-target therapy.But for successful clinical application,it is necessary to construct attenuated LM stain that is safe yet retains the potency of LM based on the full virulent pathogen.In this study,attenuated LM and recombinants of LM expressing melanoma inhibitory activity(MIA) were constructed successfully.The median lethal dose(LD 50) and invasion efficiency of attenuated LM strains were detected.The recombinants were utilized for immunotherapy of animal model of B16F10 melanoma.The level of MIA mRNA expression in tumor tissue was detected by using real-time polymerase chain reaction(PCR) with specific sequence,meanwhile the anti-tumor immune response was assayed by flow cytometric analysis and enzyme-linked immunosorbent spot(ELISPOT) assay.The results showed the toxicity and invasiveness of attenuated LM were decreased as compared with LM,and attenuated LM expressing MIA,especially the double-genes attenuated LM recombinant,could significantly induce anti-tumor immune response and inhibit tumor growth.This study implicates attenuated LM may be a safer and more effective vector for immunotherapy of melanoma.
文摘Effects of attenuated highly pathogenic pig reproductive and respiratory syndrome（HP-PRRS）TJM-F92 strain vaccine on immune antibody level against classical swine fever（CSF）and foot-and-mouth disease（FMD）were studied from October 8 to November 12 in 2014,in order to optimize vaccination program of CSF,HP-PRRS and FMD and to provide scientific guidance for animal disease control and prevention work.The results showed that attenuated HP-PRRS（TJMF92 strain）vaccine had no significant effect on immune antibody level of hog cholera lapinized virus（HCLV,ST passage cell vaccine）attenuated vaccine and FMD-O inactivated vaccines（OZK/93 strain）,and single or combined use of three vaccines received good immunization effects.
基金supported by the National Natural Science Foundation of China ( 31670957)
文摘Osteoarthritis(OA)is an inflammatory disease involving the joints that is prevalent in the global aging population.The purpose of this study is to determine whether irisin can attenuate osteoarthritis(OA)progression in anterior cruciate ligament transection(ACLT)mice models and the mechanism of irisin therapy effect on OA by increase the resistance of apoptosis in MLO-Y4 cells induced by mechanical stretch in vitro.Methods For in vivo study,3-month-old male C57BL/6 J mice were randomized to three groups,sham-operated,anterior cruciate ligament transection(ACLT)-operated treated with vehicle,and ACLT-operated treated with irisin by intraperitoneal injection once a week.Cartilage erosion was observed by HE staining.Osteoarthritis Research Society International(OARSI)scores were evaluated according to the safranin O stai-ning.The microstructure of tibia cortical bone,trabecular bone,and subchondral bone was analyzed by micro-CT and the bone histomorphometry has been administrated including mineral apposition rate(MAR).Edu staining and cck-8 were used for the detection of the proliferation of MLO-Y4 cells.For mechanical stress,cells were seeded on the collagen-I coated chamber subjected with a peak biaxial stretch of 20%at 1 Hz for 16 hours to induce apoptosis.Flow cytometry was used for the detection of apoptosis and cell cycle.TUNNEL was used for staining the apoptotic cells and rt-PCR was applied for quantifying the expression of mRNA such as Bax,Bcl-2,SOST,c-myc,Opg.Western blot was utilized to confirm the mechanism of how irisin decrease the osteocyte apoptosis.Results In vivo,irisin can attenuate articular cartilage degeneration.Irisin maintains the proportion of hyaline cartilage and calcified cartilage and keep fewer cartilage erosions in ACLT-operated mice.For immunohistochemical(IHC)staining,irisin reduced the expression of caspase3,Bax and matrix metalloproteinase-13 in both cartilage and subchondral bone.Irisin-treated ACLT group shows higher Trabecular number(Tb.N)and bone volume fraction(BV/TV)compared to the vehicle-treated ACLT group.In vitro, irisin significantly increased the proliferation of MLO-Y4 cells detected by Edu and Ki67 staining,and irisin can protect the cells from both mechanical stretchinduced apoptosis detected by FITC-PI flow cytometry and maintain the cell activity by regulating the expression of Bax,Bcl-2,and c-myc.Transcriptome sequencing shows that irisin significantly activates the MAPK signaling pathway and we confirm the result by western blot:irisin effectively activates the Erk signaling pathway through phosphorylation and has a certain activation effect on p38 signaling pathway,no activation was observed for FAK signaling pathway.Conclusions Irisin can attenuate the progression of OA by decrease the apoptosis of osteocyte,which can improve the microarchitecture of subchondral bone.Erk pathway activation plays an important role in reducing the apoptosis of osteocyte.
基金supported by grants from the National Natural Science Foundation of China for Dai (Grant No. 81472188) and Zheng (Grant No. 81702247)the Youth Development Project of TMMU for Zheng (Grant No. 2016XPY17)
文摘Objective: Cancer vaccines that rely on tumor antigen-specific CD8^+ T cell responses, are promising anti-cancer adjuvant immunotherapies. This study investigated whether genetically attenuated Plasmodium sporozoite(GAS) could be used as a novel vector to induce antigen-specific CD8^+ T cell responses against lung cancer.Methods: We constructed GAS/MAGE-A3, a recombinant GAS engineered to express the lung cancer-specific antigen, melanomaassociated antigen 3(MAGE-A3), and assessed its therapeutic effects against lung cancer.Results: Robust parasite-specific CD8αlow CD11ahigh and CD49dhigh CD11ahigh CD4^+ T cell responses as well as a MAGE-A3-specific CD8^+ T cell response were induced in GAS/MAGE-A3-immunized mice. Adoptive transfer of GAS/MAGE-A3-induced CD8^+ T cells from HLA-A2 transgenic mice into lung cancer-bearing nude mice inhibited tumor growth and prolonged survival.Conclusions: These findings demonstrate that GAS/MAGE-A3 induces a strong MAGE-A3-specific CD8^+ T cell response against lung cancer in vivo, and indicate that GAS is a novel and efficacious antigen delivery vector for antitumor immunotherapy.
