Background: Although there is a significant improvement in the living standards of people globally, a variety of disease outbreaks occurred over the time.Hepatitis B disease is contagious with a complex mode of transmission.Methods: In this paper, the effects of biomedical therapy on the treatment of hepatitis B were studied.Results: The mechanism of action was found, so as to provide a theoretical basis for the future application of biomedical therapy in the treatment of viral hepatitis.Conclusions: The results show that the method is effective.

OBJECTIVE:ATPase family, AAA domain containing 2 (ATAD2) has been found overexpressed in various cancer types and correlated with malignant status and poor prognosis. However, little is known about the clinical significance of ATAD2 in gastric cancer patients. The aim of this study was to explore the clinical and prognostic significance of ATAD2 in gastric cancer.METHODS:The mRNA and protein levels expression of ATAD2 were detected in clinical tissue samples by qRT-PCR and immunohistochemistry, respectively. We examined the ATAD2 protein expression by immunohistochemistry. Furthermore, we analyzed the association between ATAD2 expression and clinicopathological features including prognosis in 166 gastric cancer samples.RESULTS:In our results, ATAD2 mRNA and protein were highly expressed in gastric cancer samples. ATAD2 overexpression was correlated with advanced clinical stage, tumor depth, lymph node metastasis, and distant metastasis. According to the survival analysis, ATAD2 protein overexpression was a poor independent prognostic factor for gastric cancer patients.CONCLUSIONS:In summary, ATAD2 could serve as a prognostic biomarker for gastric cancer patients.

Cyclin D1 (CCND1) plays a significant role in G1-S transition of cell cycle, and phosphatase and a tensin homologue (PTEN) negatively regulate cell cycle through phosphatidylinositol 3-kinase (PI3K)/AKT signaling. CCND1 and PTEN genetic polymorphisms might induce susceptibility to the occurrence of esophageal squamous cell carcinoma (ESCC). Three hundred and four ESCC patients and 413 healthy controls from Anyang, China, were enrolled in this study. All genotyping at CCND1 (807 G/A) and PTEN (rs701848 T/C and rs2735343 C/G) were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Unconditional logistic regression model was used to analyze the correlation between the polymorphisms and the susceptibility to develop ESCC. Statistically significant differences were observed between cases and controls in distribution of genotypes or alleles at PTEN rs701848 T/C and rs2735343 C/G, with either haplotype TG or CG possessing notably higher proportion in cases than in the controls. However, such difference could not be found in the distribution of the polymorphisms at CCND1 807 G/A. In summary, the polymorphisms of PTEN rs701848 T/C and rs2735343 C/G might represent crucial modifying factors for development of ESCC.

In light of findings demonstrating that the macaque TRIM5alpha protein inhibits infection of cells by human immunodeficiency virus (HIV)-1, simian immunodeficiency virus (SIV)-based lentiviral vectors may have distinct advantages over HIV-1 vectors for the transduction of macaque hematopoietic stem cells. We evaluated the ability of an SIV vector (VRX859) encoding an antisense SIV envelope sequence and enhanced green fluorescent protein (GFP) to inhibit viral replication and to transduce rhesus CD34(+) lymphoid progenitor cells. After infection with homologous SIV strains, CD4(+) cell lines transduced with VRX859 exhibited more than 600-fold inhibition of viral replication compared with control cells. Less inhibition was observed with the divergent SIV strain SIVsmE660. Partial inhibition of a chimeric simian-human immunodeficiency virus, which contains an HIV-1 envelope in an SIV backbone, was observed, suggesting that the SIV vector also contributes to viral inhibition independent of the antisense envelope inhibitor. Transduction of rhesus CD34(+) cells with VRX859 at various multiplicities of infection resulted in transduction efficiencies comparable to those obtained with the HIV vector VRX494. However, when we evaluated transduction of rhesus T lymphocyte progenitors by examining GFP expression in CD4(+) T cells derived from transduced CD34(+) cells, we observed more efficient transduction with the SIV-based vector. GFP(+)CD4(+) T cells derived from VRX859-transduced CD34(+) cells strongly inhibited SIVmac239 replication as compared with control CD4(+) T cells. The ability of this SIV-based vector to mediate potent inhibition of SIV replication, coupled with its efficient transduction of rhesus hematopoietic progenitor cells, make it an important candidate for proof-of-principle experiments of stem cell gene therapy in the SIV-macaque model.

This paper presents a new tracking circuit design without standby leakage current issue for 2.5V/3.3V tolerant I/O buffer, which is suitable for the I/O cells in the mixed-voltage applications with different driving capabilities. One set of mixed-voltage I/O cell with the new proposed 2.5V/3.3V tolerant I/O buffer circuit has been designed and drawn in a 0.13-mu m salicided CMOS process. The new tracking circuit can be also applied in other CMOS processes to serve different mixed-voltage I/O interfaces.

This paper presents a new tracking circuit design without standby leakage current issue for 2.5V/3.3V tolerant I/O buffer, which is suitable for the I/O cells in the mixed-voltage applications with different driving capabilities. One set of mixed-voltage I/O cell with the new proposed 2.5V/3.3V tolerant I/O buffer circuit has been designed and drawn in a 0.13-mum salicided CMOS process. The new tracking circuit can be also applied in other CMOS processes to serve different mixed-voltage I/O interfaces

We have constructed a human immunodeficiency virus type 1 (HIV-1)-based lentiviral vector expressing a 937-base antisense sequence against the HIV-1 envelope gene. Transduction of CD4(+) T lymphocytes with this vector results in expression of the therapeutic antisense sequence and subsequent inhibition of productive HIV-1 replication. In this report, we examined the effect of antisense-mediated suppression on the potential development of virus escape mutants using a permissive T-cell line cultured under conditions that over serial passages specifically allowed for generation and amplification of mutants selected for by antisense pressure. In the resulting virus clones, we found a significant increase in the number of deletions at the envelope target region (91% compared to 27.5% in wild-type HIV). Deletions were most often greater than 1 kb in length. These data demonstrate for the first time that during antisense-mediated suppression of HIV, mutants develop as a direct result of selective pressure on the HIV genomic RNA. Interestingly, in clones where deletions were not observed, there was a high rate of A-G transitions in mutants at the antisense target region but not outside this region, which is consistent with those mutations that are predicted as a result of antisense-mediated modification of double-stranded RNA by the enzyme double-stranded RNA-specific adenosine deaminase. These clones were not found to be escape mutants, as their replicative ability was severely attenuated, and they did not replicate in the presence of vector.

A dynamic-holding-voltage silicon-controlled rectifier (DHVSCR) device is proposed and verified in a 0.25-/spl mu/m/2.5-V salicided CMOS process. In the DHVSCR device structure, the control nMOS and pMOS transistors are directly embedded in SCR device structure. The proposed DHVSCR device has the characteristics of tunable holding voltage and holding current by changing the gate voltage of embedded nMOS and pMOS. Under normal circuit operating condition, the DHVSCR has a holding voltage higher than the supply voltage without causing a latch-up issue. Under an electrostatic discharge (ESD) stress condition, the DHVSCR has a lower holding voltage to effectively clamp the overshooting ESD voltage. From the experimental results, the DHVSCR with a device width of 50 /spl mu/m can sustain a human-body-model ESD level of 5.6 kV.

We report the design of a unique two‐plasmid production system for the first lentiviral vector to be evaluated in humans, VRX496. VRX496 is an optimized VSV‐G pseudotyped vector derived from HIV‐1 that expresses antisense to the HIV envelope gene. We found that a two‐plasmid approach to production resulted in higher vector production titers when compared with a three‐plasmid approach, which is particularly important for vector production at the large scale. Therefore, we carefully designed a single packaging construct, VIRPAC, for safety by reducing its homology with VRX496 and by insertion of functionally validated genetic elements designed to reduce the risk of generation of a replication‐competent lentivirus (RCL). A native cis‐acting ribozyme is used to prevent read through into the envelope gene from the upstream gag‐pol genes in the packaging vector, thus preventing RNAs containing gag‐pol and env together for comparable safety to a three‐plasmid system. We demonstrate that there is no significant in vivo vector mobilization using a primary SCID‐hu mouse transplantation model, which correlates with the presence of an anti‐HIV payload and suggests that inclusion of antisense may be a useful tool to restrict mobilization in other vector constructs. Gene transfer is achieved using a one‐step transduction procedure that is simple and clinically translatable, which reaches stable transduction efficiencies of >99% in CD4 + T lymphocytes within 3 days of culture initiation. Copyright © 2004 John Wiley & Sons, Ltd.

Lentivirus-based vectors have been considered to offer increased safety in terms of oncogenesis in part since contrary to oncoretroviruses, lentiviruses are not associated with oncogenesis. In support of this, leukemia is not a recognized side effect of HIV infection, even though memory T cells are known to harbor virus for years; additionally, approximately 1 out of every three proviruses are replication incompetent, and therefore cannot kill the host cell, yet these cells also do not turn leukemic. Until recently, retrovirus-mediated oncogenesis remained a theoretical risk, until the two children in the French X-linked SCID trial developed leukemia. Although the development of leukemia may have as much to do with the type of cells used in gene therapy as the vector used, the unfortunate event brought to the forefront the need to determine the specific relative safety of different retroviral vectors. In order to determine the relative safety of our HIV-1-based lentiviral vector to the MLV vector, we are investigating the enhancer activity of the HIV LTR in comparison to the MLV LTR and an enhancer negative promoter control. Preliminary studies in NIH 3T3 cells indicate that the MLV LTR contains an enhancer effect greater than that of the HIV LTR. Currently, studies are being conducted in the CD34+ cells isolated from one of the two children that developed leukemia in the X-linked SCID trial, in order to test the relative enhancer activities in the cellular environment where oncogenesis was first observed in vivo. In parallel, we used LAM-PCR to determine the insertion sites of an HIV-1 based lentivirus vector in several HIV+ patients undergoing evaluation in the first lentiviral vector clinical trial. We compared the distribution of the insertions among the chromosomes to those published in the Bushman publication of 2003; we found a similar pattern of random distribution among all chromosomes except chromosome 18, which appears to be partially refractory to integration. Details of the insertion sites will be presented including the specific location of the insertion within the chromosome, and proximity to genes with oncogenic potential.