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Ubiquitin-specific protease 22 (USP22) aberrance has been implicated in several malignancies; however, whether USP22 plays a role in anaplastic thyroid carcinoma (ATC) remains unclear. Here, we report that USP22 expression is highly elevated in ATC tissues, which positively correlated with tumor size, extracapsular invasion, clinical stages, and poor prognosis of ATC patients. In vitro assays showed that USP22 depletion suppressed ATC cell survival and proliferation by decreasing Rb phosphorylation and cyclin D2, inactivating Akt, and simultaneously upregulating Rb; USP22 silencing restrained cell migration and invasion by inhibiting epithelial-mesenchymal transition; USP22 knockdown promoted mitochondrion- mediated and caspase-dependent apoptosis by upregulating Bax and Bid and promoting caspase-3 activation. Consistent with in vitro findings, downregulation of USP22 in ATC cells impeded tumor growth and lung metastasis in vivo. These results raise the applicability for USP22 as a useful predictor of ATC prognosis and a potential therapeutic target for ATC.

This paper studies free vibration of horn-shaped single-walled carbon nanotube (SWCNT) carrying a nanoparticle, which is used to model a mass sensor. A non-uniform cantilever with a concentrated mass at the free end is analyzed according to the nonlocal Euler–Bernoulli beam theory. A governing equation of a horn-shaped SWCNT-based mass sensor is established. The transfer function method incorporating with the perturbation method is utilized to obtain the natural frequencies of a nonlocal Euler–Bernoulli beam with an attached nanoparticle. The effects of the geometry parameter, the nonlocal parameter and the attached mass on the natural frequencies or frequency shift are discussed. Obtained results show that the SWCNT-based mass sensor becomes more sensitive to the frequency shift due to the attached mass when the free end becomes sharper. In addition, there exists a horn-shaped SWCNT with special geometry, for which the fundamental frequencies are independent of size effect.

The potential of single-layered graphene sheet (SLGS) as a nanomechanical sensor is explored. A simply supported SLGS carrying a nanoparticle at any position is modeled as a rectangular nanoplate with a concentrated micro-mass. Based on the nonlocal Kirchhoff theory of plates which incorporates size effects into the classical theory, the natural frequencies of a nanomechanical sensor are derived using the Galerkin method. The effects of the mass and position of the nanoparticle on the frequency shift are discussed. In the absence of the nonlocal parameter, the frequencies reduce to the results of the classical model, in agreement with those using the finite element method. The obtained results show that when the mass of the attached nanoparticle increases or its location is closer to the plate center, the natural frequency decreases, but frequency shift increases. Small scale effect diminishes the frequency shift. Decreasing the plate side length also increases the frequency shift. Obtained results are helpful to the design of SLGS-based resonator as nanomechanical mass sensor.

Background Although DNA vaccine is considered as the next generation of vaccine, most DNA vaccine candidates are still suffering from the relatively weak immunogenicity despite the increased dosage of plasmid DNA administered. In order to enhance the immune responses elicited by a codon-optimized HIV gag DNA vaccine, a modified plasmid vector pDRVI1.0 and a booster immunization with replicating Tiantan vaccinia (RTV) strain expressing the same gene were employed. Methods Vector pDRVI1.0 was constructed through inserting the 72-bp element from the SV40 enhancer, which was reported promoting nuclear transport of plasmid DNA, to the upstream of cytomegalovirus enhancer/promoter region of the plasmid vector pVR1012. Gene expression levels from expression plasmids based on pDRVI1.0 and pVR1012 were tested. Humoral and cellular immune responses induced by DNA vaccine alone or DNA prime-RTV boost regimen were determined in mice. Results It was shown that the 72-bp element significantly enhanced the gene expression level in non-dividing cells. gag-specific humoral and cellular immune responses induced by DNA vaccination were both significantly improved, while the Th1/Th2 balance was not obviously affected by the 72-bp element. RTV boosting further significantly enhanced DNA vaccine-primed antibody and T cell responses in a Th1-biased manner. Conclusions The 72-bp SV40 enhancer element should be included in the DNA vaccine vector and RTV strain is a very efficient live vector for boosting immunization.

To investigate the expression of NKG2A on cytotoxic natural killer (NK) cells in HIV-1-infected patients.A cross-sectional study was conducted to investigate the NKG2A expression on NK cell subsets among HIV-infected individuals at different clinical stages and HIV negative controls.113 HIV-1 infected and 43 uninfected individuals were enrolled in this study. The HIV-1 infected patients were further categorized into three groups, CD4 cell count500 cells/microl (n = 44), CD4 cell count of 200-500 cells/microl (n = 49) and CD4 cell count200 cells/microl (n = 20). Flow cytometry was used to determine the expression of NKG2A on NK cell subsets. A flow-based assay was employed to quantify the NK cytotoxicity.Fewer cytotoxic NK cells and more dysfunctional NK cells were observed in patients with advanced clinical conditions. Higher NKG2A expression level in cytotoxic NK subset were found in later stages HIV infection, 25.6% in groups with CD4 cell count500 cells/microl, 40.9% in groups with CD4 cell count 200-500 cells/microl and 48.3% in groups with CD4 cell count200 cells/microl. Lower NK mediated cytotoxicity, which was associated with the decrease in cytotoxic NK cell number and higher NKG2A expression on cytotoxic NK subsets, was found in AIDS patients compared with patients at early stage of infection. A reverse association between the percentage of NKG2A positive cells in cytotoxic NK subset and CD4 cell count was observed in all HIV-1 infected groups.Fewer cytotoxic NK cells and higher NKG2A expression in cytotoxic NK subset was found in patients in late stage HIV infection. Such a phenomenon may relate to the escape of HIV-1-infected CD4+ T cells from being attacked by NK cells.

Although DNA vaccine is considered as the next generation of vaccine, most DNA vaccine candidates are still suffering from the relatively weak immunogenicity despite the increased dosage of plasmid DNA administered. In order to enhance the immune responses elicited by a codon-optimized HIV gag DNA vaccine, a modified plasmid vector pDRVI1.0 and a booster immunization with replicating Tiantan vaccinia (RTV) strain expressing the same gene were employed.Vector pDRVI1.0 was constructed through inserting the 72-bp element from the SV40 enhancer, which was reported promoting nuclear transport of plasmid DNA, to the upstream of cytomegalovirus enhancer/promoter region of the plasmid vector pVR1012. Gene expression levels from expression plasmids based on pDRVI1.0 and pVR1012 were tested. Humoral and cellular immune responses induced by DNA vaccine alone or DNA prime-RTV boost regimen were determined in mice.It was shown that the 72-bp element significantly enhanced the gene expression level in non-dividing cells. gag-specific humoral and cellular immune responses induced by DNA vaccination were both significantly improved, while the Th1/Th2 balance was not obviously affected by the 72-bp element. RTV boosting further significantly enhanced DNA vaccine-primed antibody and T cell responses in a Th1-biased manner.The 72-bp SV40 enhancer element should be included in the DNA vaccine vector and RTV strain is a very efficient live vector for boosting immunization.

Although HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity.Primary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients' plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay.Six primary viral strains were isolated from 4 separated regions. Isolates LTG0213, LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691LTG0214XJN0091 approximately SHXDC0041.The neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.

To investigate the biological characteristics of the HIV-1 isolates circulating in China and to define the association of these properties with env V3 loop sequence variability.Primary viruses were isolated from fresh peripheral blood mononuclear cells (PBMCs) using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells; meanwhile, their coreceptor usage was determined with GHOST-cell lines which stably express CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, HIV-1 V3 and its flanking region sequences were amplified by nest-polymerase chain reaction (nest-PCR) and sequenced. A GCG software was used to translate the DNA sequences into polypeptide sequences.Five primary viral strains were isolated from 3 different regions in China. The isolates LTG0213 and LTG0214 induced syncytia in MT-2 cells and used CXCR4 as coreceptor. The isolates XJN0021, XJN0091, and SHXDC0041 did not induce syncytia and used CCR5 as coreceptor. There were obvious differences between X4/SI and R5/NSI viruses in env V3 loop sequences. A consensus motif at the positions 8, 11, 18, and 25 in V3 loop was identified as follows: a sequence as "8-TXXS/GXXXXXXR/QXXXXXXE/D-25" will predict the usage of CCR5 coreceptor; a sequence replacing these positions with basic amino acids (except position 25) will very likely predict the usage of CXCR4 coreceptor.The biological characteristics of HIV isolates are linked to env V3 loop sequence variability: introducing basic amino acids (or translating from acidic amino acids into neutral amino acids) at the positions 8, 11, 18, and 25 in V3 loop will change viral strain's biological phenotype from NSI/CCR5 to SI/CXCR4. The biological phenotype of HIV-1 can be predicted with V3 loop sequence analysis.

To investigate the immunogenicity of HIV vaccine vTKgpe based on Vaccinia Virus Tiantan vector in mice and rabbits.Mice were inoculated with HIV vaccine vTKgpe by intramuscular (i.m.), intradermal (i.d.) or subcutaneous (s.c.) injections. Blood sample were collected every week, and then antibodies against HIV and vaccinia virus vector were detected. At week 4, some mice were killed and cellular immune responses were examined by flow cytometer. Additionally two rabbits were vaccinated subcutaneously, blood sample were tested as done with mice.In mice i.m. and s.c. groups, HIV specific antibodies emerged at week 2 and declined at week 4. Antibodies against vector elevated rapidly at week 4, and potentially affected HIV specific antibody detection. Cellular immune responses were only detected in s.c. group. Serum of rabbit showed that anti-HIV antibody appeared at week 2 and maintained for several weeks.Vaccine vTKgpe innoculated by i.m. and s.c routes inclined to induce humoral immune responses in mice, but in i.d. group, inclined to induce cellular immune responses. Response to the recombinant vaccinia virus was more sensitive in rabbit than in mice.