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1.
Takahiro Yamada Takehiro Togashi Hiroyuki Tsutsumi Masahiro Imamura Hitoshi Okubo Mihiro Okabe Noriko Takamuro Kunio Tashiro Koichi Yano Nagafumi Yamamoto Yukiko Hirakawa Hisanori Minakami 《Microbiology and immunology》2014,58(8):427-431
As there is a risk of MTCT of HTLV‐1, the HSGP HTLV‐1 MTCT was organized in 2011. To determine how many pregnant women are infected with HTLV‐1 in Hokkaido, which is the northernmost and the second largest island in Japan with a population of 5 467 000 and 39 392 newborns in 2011, the HSGP HTLV‐1 MTCT asked all facilities that may care for pregnant women in Hokkaido in July 2013 to provide information on the number of pregnant women who underwent screening for anti‐HTLV‐1 antibody using particle agglutination or chemiluminescent enzyme immunoassay, and the numbers of those with positive, equivocal, and negative test results in the screening and confirmation tests using western blotting or PCR methods in 2012, respectively. A total of 111 facilities participated in this study and provided information on 33 617 pregnant women who underwent screening in 2012, corresponding to approximately 85% of all pregnant women who gave birth in Hokkaido in 2012. Of 81 candidates for a confirmation test because of positive (n = 77) or equivocal (n = 4) results on screening, 63 (78%) underwent the confirmation test and, finally, 34 (0.1%) and 33 563 (99.8%) women were judged to be HTLV‐1 carriers and non‐carriers, respectively. It was concluded that the prevalence rate of HTLV‐1 carriers was low, one per 1000 pregnant women in Hokkaido. Approximately 40 infants are born yearly to mothers infected with HTLV‐1 in Hokkaido. 相似文献
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Elizabeth R. Brown 《Biometrics》2010,66(4):1266-1274
Summary We present a Bayesian model to estimate the time‐varying sensitivity of a diagnostic assay when the assay is given repeatedly over time, disease status is changing, and the gold standard is only partially observed. The model relies on parametric assumptions for the distribution of the latent time of disease onset and the time‐varying sensitivity. Additionally, we illustrate the incorporation of historical data for constructing prior distributions. We apply the new methods to data collected in a study of mother‐to‐child transmission of HIV and include a covariate for sensitivity to assess whether two different assays have different sensitivity profiles. 相似文献
3.
Guosheng Su Yesheng Wei Lihua Qin Lida Mo 《Asia-Pacific Journal of Blood Types and Genes》2018,2(4):223-231
This study aims to investigate changes in viral load, T lymphocyte subsets and other main biochemical indexes of HIV/AIDS in the prevention of mother to child transmission (PMTCT). In this study, 152 pregnant women with HIV/AIDS enrolled into our hospital from January 2013 to June 2015 were chosen as objects. Changes in viral load, T lymphocyte subsets and other main biochemical indexes of HIV/AIDS were tested and compared before and after 3 months of PMTCT and in neonatals one week after birth. The CD4/CD8 examination result, and difference in CD4 before and after prevention (in the newborns after a week) was statistically significant (P < 0.05), and the rest showed no statistical significance. For the dynamic analysis of main biochemical test results: K+, Na+, Cl-, BG, OS, BUN, BUN/Cr, UA,TDIL, DBIL, TP, ALB, CK, LDH, HDL, LDL and other indexes before and after prevention attained statistical significances (P < 0.05 or above). The same sample in the three groups was detected by repeated analysis of variance, K+, Na+, Cl-, BG, OS, BUN/Cr, UA, DBI L, ALB, CK, LDH, HDL, LDL and other indexes also showing P at less than 0.05 or above, among which K+, Cl-, CK, LDL showed homogeneity of variance, while Na+, BG, OS, BUN/Cr, UA, DBIL, ALB, LDH, HDL showed unequal homogeneity of variance. The study suggests that the dynamic analysis of viral load, T lymphocyte subsets and main biochemical indexes before and after PMTCT in HIV/AIDS are important means to evaluate the dose and treatment of antiretroviral drugs. Monitoring of above indexes is helpful to judge and analyze the condition of the maternal body at various stages, so antiviral drug treatment can be adjusted. 相似文献
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段江凯;陈亮 《中国生物化学与分子生物学报》2025,41(5):664-677
目前,获得性免疫缺陷综合征(acquired immune deficiency syndrome, AIDS)已成为严重威胁世界人民健康的公共卫生问题,它破坏人体的免疫系统,使人体因丧失对各种疾病的抵抗能力而发病并死亡。根除潜伏存在的人类免疫缺陷病毒(human immunodeficiency virus, HIV),实现功能性治愈,从而限制AIDS的发展,并改善患者的生活质量,是需要迫切解决的问题。表观遗传学主要研究基因序列改变之外的可遗传的基因表达调控。HIV的基因表达调控受到多种表观遗传因素的影响,并涉及到多种机制。了解HIV感染过程中相关的表观遗传机制,对于清除潜伏的病毒和在未来实现对AIDS的控制与治疗至关重要。因此,我们将对HIV感染过程中的相关表观遗传调控方式及其机制进行阐述,重点介绍DNA甲基化、组蛋白修饰、非编码RNA调控和RNA修饰等表观遗传修饰方式,总结这些调控对于HIV潜伏、激活和维持过程的影响。同时,将HIV感染过程中的表观遗传调控与其关联的信号通路联系起来,并根据近年来在HIV功能性治疗策略方面取得的成果与挑战进行展望,旨在阐明表观遗传在HIV调控方面的重要作用,以期为未来根据表观遗传调控实现AIDS的控制以及开发治疗药物提供新的理论基础和研究方向。 相似文献
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Larson AM Hsu BB Rautaray D Haldar J Chen J Klibanov AM 《Biotechnology and bioengineering》2011,108(3):720-723
Coating surfaces with N-alkylated polyethylenimines (PEIs), namely branched N,N-hexyl,methyl-PEI via covalent attachment to glass or linear N,N-dodecyl,methyl-PEI by physical deposition (\"painting\") onto polyethylene, enables the resultant materials to quickly and efficiently disinfect aqueous solutions of (non-enveloped) poliovirus and rotavirus. 相似文献
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Zain Bengali Jennifer C. Rea Romie F. Gibly Lonnie D. Shea 《Biotechnology and bioengineering》2009,102(6):1679-1691
Non‐viral gene delivery by immobilization of complexes to cell‐adhesive biomaterials, a process termed substrate‐mediated delivery, has many in vitro research applications such as transfected cell arrays or models of tissue growth. In this report, we quantitatively investigate the efficiency of gene delivery by surface immobilization, and compare this efficiency to the more typical bolus delivery. The ability to immobilize vectors while allowing cellular internalization is impacted by the biomaterial and vector properties. Thus, to compare this efficiency between vector types and delivery methods, transfection conditions were initially identified that maximized transgene expression. For surface delivery from tissue culture polystyrene, DNA complexes were immobilized to pre‐adsorbed serum proteins prior to cell seeding, while for bolus delivery, complexes were added to the media above adherent cells. Mathematical modeling of vector binding, release, and cell association using a two‐site model indicated that the kinetics of polyplex binding to cells was faster than for lipoplexes, yet both vectors have a half‐life on the surface of approximately 17 min. For bolus and surface delivery, the majority of the DNA in the system remained in solution or on the surface, respectively. For polyplexes, the efficiency of trafficking of cell‐associated polyplexes to the nucleus for surface delivery is similar or less than bolus delivery, suggesting that surface immobilization may decrease the activity of the complex. The efficiency of nuclear association for cell‐associated lipoplexes is similar or greater for surface delivery relative to bolus. These studies suggest that strategies to enhance surface delivery for polyplexes should target the vector design to enhance its potency, whereas enhancing lipoplex delivery should target the material design to increase internalization. Biotechnol. Bioeng. 2009;102: 1679–1691. © 2008 Wiley Periodicals, Inc. 相似文献
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Hyunjung Kim Yun Mi Bae Hyun Ah Kim Hyesun Hyun Gwang Sig Yu Joon Sig Choi Minhyung Lee 《Journal of cellular biochemistry》2010,110(3):743-751
Linear polyethylenimine (25 kDa, LPEI25k) has been shown to be an effective non‐viral gene carrier with higher transfection and lower toxicity than branched polyethylenimine (BPEI) of comparable molecular weight. In this study, dexamethasone was conjugated to LPEI25k to improve the efficiency of gene delivery. Dexamethasone is a synthetic glucocorticoid receptor ligand. Dexamethasone‐conjugated LPEI25k (LPEI–Dexa) was evaluated as a gene carrier in various cells. Gel retardation assays showed that LPEI–Dexa completely retarded plasmid DNA (pDNA) at a 0.75:1 weight ratio (LPEI/pDNA). LPEI–Dexa had the highest transfection efficiency at a 2:1 weight ratio (LPEI–Dexa/DNA). At this ratio, the size of the LPEI–Dexa/pDNA complex was approximately 125 nm and the zeta potential was 35 mV. LPEI–Dexa had higher transfection efficiency than LPEI and Lipofectamine 2000. In addition, the cytotoxicity of LPEI–Dexa was much lower than that of BPEI (25 kDa, BPEI25k). In conclusion, LPEI–Dexa has a high transfection efficiency and low toxicity and can therefore be used for non‐viral gene delivery. J. Cell. Biochem. 110: 743–751, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
10.
Park MR Kim HW Hwang CS Han KO Choi YJ Song SC Cho MH Cho CS 《The journal of gene medicine》2008,10(2):198-207
BACKGROUND: Polyethylenimine (PEI) is toxic although it is one of the most successful and widely used gene delivery polymers with the aid of the proton sponge effect. Therefore, development of new novel gene delivery carriers having high efficiency with less toxicity is necessary. METHODS: In this study, a degradable poly(ester amine) carrier based on poly(ethylene glycol) diacrylate (PEGDA) and low molecular weight linear PEI was prepared. Furthermore, we compared the gene expression of the polymer/DNA complexes using two delivery methods: intravenous administration as an invasive method and aerosol as a non-invasive method. RESULTS: The synthesized polymer had a relatively small molecular weight (MW = 7980) with 25 h half-life in vitro. The polymer/DNA complexes were formed at an N/P ratio of 9. The particle sizes and zeta-potentials of the complexes were dependent on N/P ratio. Compared to PEI 25K, the newly synthesized polymer exhibited high transfection efficiency with low toxicity. Poly(ester amine)-mediated gene expression in the lung and liver was higher than that of the conventional PEI carrier. Interestingly, non-invasive aerosol delivery induced higher gene expression in all organs compared to intravenous method in an in vivo mice study. Such an expressed gene via a single aerosol administration in the lung and liver remained unchanged for 7 days. CONCLUSIONS: Our study demonstrates that poly(ester amine) may be applied as an useful gene carrier. 相似文献
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Lavigne MD Pennadam SS Ellis J Yates LL Alexander C Górecki DC 《The journal of gene medicine》2007,9(1):44-54
BACKGROUND: Successful non-viral gene targeting requires vectors to meet two conflicting needs-strong binding to protect the genetic material during transit and weak binding at the target site to enable release. Responsive polymers could fulfil such requirements through the switching of states, e.g. the chain-extended coil to chain-collapsed globule phase transition that occurs at a lower critical solution temperature (LCST), in order to transport nucleic acid in one polymer state and release it in another. METHODS: The ability of new synthetic polycations based on poly(ethyleneimine) (PEI) with grafted neutral responsive poly(N-isopropylacrylamide) (PNIPAm) chains to condense DNA into particles with architectures varying according to graft polymer LCST was assessed using a combination of fluorescence spectroscopy, dynamic light scattering (DLS), zeta sizing, gel retardation and atomic force microscopy studies. Transfection assays were conducted under experimental conditions wherein the polymer components were able to cycle across their LCST. RESULTS: Two PEI-PNIPAm conjugate polymers with different LCSTs displayed coil-globule transitions when complexed to plasmid DNA, leading to variations in molecular architecture as shown by changes in emission maxima of an environment-sensitive fluorophore attached to the PNIPAm chains. Gel retardation assays demonstrated differences in electrophoretic mobilities of polymer-DNA complexes with temperatures below and above polymer LCSTs. Atomic force micrographs showed changes in the structures of polymer-DNA complexes for a polymer undergoing a phase transition around body temperature but not for the polymer with LCST outside this range. Transfection experiments in C2C12 and COS-7 cells demonstrated that the highest expression of transgene occurred in an assay that involved a 'cold-shock' below polymer LCST during transfection. CONCLUSIONS: Designed changes in thermoresponsive polycation vector configuration via temperature-induced phase transitions enhanced transgene expression. The results indicate that changes in molecular architecture induced by a carefully chosen stimulus during intracellular trafficking can be used to enhance gene delivery. 相似文献
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Sergio E. Martinez Joseph D. Bauman Kalyan Das Eddy Arnold 《Protein science : a publication of the Protein Society》2019,28(3):587-597
Stavudine (d4T, 2′,3′‐didehydro‐2′,3′‐dideoxythymidine) was one of the first chain‐terminating nucleoside analogs used to treat HIV infection. We present the first structure of the active, triphosphate form of d4T (d4TTP) bound to a catalytic complex of HIV‐1 RT/dsDNA template‐primer. We also present a new strategy for disulfide (S–S) chemical cross‐linking between N6 of a modified adenine at the second overhang base to I63C in the fingers subdomain of RT. The cross‐link site is upstream of the duplex‐binding region of RT, however, the structure is very similar to published RT structures with cross‐linking to Q258C in the thumb, which suggests that cross‐linking at either site does not appreciably perturb the RT/DNA structures. RT has a catalytic maximum at pH 7.5. We determined the X‐ray structures of the I63C‐RT/dsDNA/d4TTP cross‐linked complexes at pH 7, 7.5, 8, 8.5, 9, and 9.5. We found small (~0.5 Å), pH‐dependent motions of the fingers subdomain that folds in to form the dNTP‐binding pocket. We propose that the pH‐activity profile of RT relates to this motion of the fingers. Due to side effects of neuropathy and lipodystrophy, use of d4T has been stopped in most countries, however, chemical modification of d4T might lead to the development of a new class of nucleoside analogs targeting RNA and DNA polymerases. 相似文献
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Katakura H Harada A Kataoka K Furusho M Tanaka F Wada H Ikenaka K 《The journal of gene medicine》2004,6(4):471-477
BACKGROUND: Although some cationic reagents, such as polybrene, improve gene transduction in vitro, their use in vivo is prohibited due to their toxicity to the exposed cells. This paper demonstrates that a new cationic reagent, poly(ethylene glycol)-poly(L-lysine) block copolymer (PEG-PLL), improves gene transduction with retroviral vectors without increasing cell toxicity. METHODS: A retroviral vector derived from the Moloney leukemia virus, containing the lacZ gene, was modified with PEG-PLL prior to transduction into NIH3T3, Lewis lung carcinoma, and primary cultured mouse brain cells. LacZ transduction efficacy was evaluated by counting the number of X-Gal-positive cells. RESULTS: We have demonstrated that PEG-PLL is able to stably modify the viral particle surface due to the affinity of the PEG moiety to the biomembrane, and neutralizes negative charges by the cationic nature of the poly-lysine residue. Thus, PEG-PLL increased the gene transduction efficiency and minimized cell toxicity because free PEG-PLL was removable by centrifugation. We have shown that PEG-PLL increased the viral gene transduction efficiency 3- to 7-fold with NIH3T3 or Lewis lung carcinoma cell lines without increasing cytotoxicity. It improved retroviral gene transduction efficacy even against labile cells, such as primary cultured brain cells. CONCLUSIONS: PEG-PLL is a novel reagent that improves retroviral gene transduction efficacy without increasing cytotoxicity. 相似文献
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《Bioscience, biotechnology, and biochemistry》2013,77(9):1777-1780
The effect of a koji (Aspergillus awamori mut.) extract on the caffeoylquinic acid derivatives purified from sweetpotato (Ipomoea batatas L.) leaves was examined to develop the mass production of caffeic acid. A koji extract hydrolyzed the caffeoylquinic acid derivatives, chlorogenic acid, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid and 3,4,5-tri-O-caffeoylquinic acid, to caffeic acid. Furthermore, the koji extract also converted the major polyphenolic components from sweetpotato, burdock (Arctium lappa L.), and mugwort (Artemisia indica var. maximowiczii) leaves to caffeic acid. These results suggest that the production of caffeic acid from plant resources containing caffeoylquinic acid derivatives is possible. 相似文献
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An effective means of facilitating DNA vaccine delivery to antigen presenting cells is through biodegradable microspheres. Microspheres offer distinct advantages over other delivery technologies by providing release of DNA vaccine in its bioactive form in a controlled fashion. In this study, biodegradable poly(D,L-lactide-co-glycolide) (PLGA) microspheres containing polyethylenimine (PEI) condensed plasmid DNA (pDNA) were prepared using a 40 kHz ultrasonic atomization system. Process synthesis parameters, which are important to the scale-up of microspheres that are suitable for nasal delivery (i.e., less than 20 microm), were studied. These parameters include polymer concentration; feed flowrate; volumetric ratio of polymer and pDNA-PEI (plasmid DNA-polyethylenimine) complexes; and nitrogen to phosphorous (N/P) ratio. PDNA encapsulation efficiencies were predominantly in the range 82-96%, and the mean sizes of the particle were between 6 and 15 microm. The ultrasonic synthesis method was shown to have excellent reproducibility. PEI affected morphology of the microspheres, as it induced the formation of porous particles that accelerate the release rate of pDNA. The PLGA microspheres displayed an in vitro release of pDNA of 95-99% within 30 days and demonstrated zero order release kinetics without an initial spike of pDNA. Agarose electrophoresis confirmed conservation of the supercoiled form of pDNA throughout the synthesis and in vitro release stages. It was concluded that ultrasonic atomization is an efficient technique to overcome the key obstacles in scaling-up the manufacture of encapsulated vaccine for clinical trials and ultimately, commercial applications. 相似文献
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HIV-1 can be considered an infection of the immune system, resulting in progressive and ultimately profound immune suppression. The availability of highly active antiretroviral therapy (HAART) has resulted in dramatic changes in the disease course in persons fortunate enough to have access to these medications, but long-term therapy is limited by the development of resistance as well as toxicities of the potent medication regimens. Emerging data indicate that individuals who have non-progressive clinical course control HIV-1 immunologically. This has bolstered hope that the immune response might be effectively augmented in persons with HIV infection. Recent data indicating that immediate treatment of acute infection leads to augmentation of antiviral immune responses have provided evidence that the immune system might be enhanced in certain situations. Therefore, investigation in the reconstitution of anti-HIV immune response in patients under HAART should provide encouragement for continuing to explore methods to obtain meaningful and durable immune enhancement as an adjunct to HAART in HIV-1 infection. 相似文献
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BACKGROUND: Gene delivery by non-specific adsorption of non-viral vectors to protein-coated surfaces can reduce the amount of DNA required, and also increase transgene expression and the number of cells expressing the transgene. The protein on the surface mediates cell adhesion and vector immobilization, and functions to colocalize the two to enhance gene delivery. This report investigates the mechanism and specificity by which the protein coating enhances gene transfer, and determines if the protein coating targets the vector for internalization by a specific pathway. METHODS: Proteins (FBS, BSA, fibronectin, collagen I, and laminin) were dried onto culture dishes, followed by PEI/DNA complex adsorption for surface delivery. Reporter genes were employed to characterize transfection as a function of the protein identity and density. Vector immobilization was measured using radiolabeled plasmid, and internalization was quantified in the presence and absence of the endocytosis inhibitors chlorpromazine and genistein. RESULTS: Fibronectin coating yielded the greatest expression for PEI/DNA polyplexes, with maximal expression at intermediate protein densities. Expression in control studies with bolus delivery was independent of the protein identity. Substrate binding was independent of the protein identity; however, internalization was greatest on surfaces coated with fibronectin and collagen I. Inhibition of caveolae-mediated endocytosis reduced gene expression more than clathrin-mediated endocytosis. Similarly, inhibition of caveolae-mediated endocytosis significantly reduced the intracellular levels of DNA. CONCLUSIONS: Fibronectin at intermediate densities mediated the highest levels of transgene expression, potentially by targeting internalization through caveolae-mediated endocytosis. Substrate modifications, such as the identity and density of proteins, provide an opportunity for modification of biomaterials for enhancing gene expression. 相似文献
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Antiviral activities of acyclovir (9-[(2-hydroxyethoxy) methyl] guanine, ACV), penciclovir (9-[4-hydroxy-3-(hydroxymethyl) butyl] guanine, PCV), ganciclovir ([9-(1,3-dihydroxy-2-propoxy) methyl] guanine, GCV), and foscarnet (phosphonoformic acid, PFA) were determined against Human Herpesvirus 6 (HHV-6) by flow cytometric technique. The technique is based on the detection of gp116 antigen expression in virus infected cells. Susceptibility was defined in terms of drug concentration which reduced the number of cells expressing HHV-6 gp116 antigen with a mean fluorescent intensity (MFI) by 50% as compared to virus infected untreated cells. GCV was found to be most effective against HHV-6 followed by PFA, PCV and ACV. For HHV-6A, the mean 50% inhibitory concentrations (IC50) of GCV and PFA were found to be 3.4 microM and 34.7 microM respectively, whereas the IC50 of ACV and PCV were found to be 53.7 microM and 37.9 microM respectively. For HHV-6B, the IC50 of GCV and PFA were found to be 5.7 microM and 71.4 microM respectively, whereas the IC50 of ACV and PCV were found to be 119.0 microM and 77.8 microM respectively. Flow cytometry is a valuable technique for the evaluation of antiviral compounds against viruses including HHV-6. 相似文献
19.
Vectors derived from adeno-associated virus type 2 (AAV2) are promising gene delivery vehicles, but it is still challenging to get the large number of recombinant adeno-associated virus (rAAV) particles required for large animal and clinical studies. Current transfection technology requires adherent cultures of HEK 293 cells that can only be expanded by preparing multiple culture plates. A single large-scale suspension culture could replace these multiple culture preparations, but there is currently no effective co-transfection scheme for generating rAAV from cells in suspension culture. Here, we weaned HEK 293 cells to suspension culture using hydrogel-coated six-well culture plates and established an efficient transfection strategy suitable for these cells. Then the cultures were gradually scaled up. We used linear polyethylenimine (PEI) to mediate transfection and obtained high transfection efficiencies ranging from 54% to 99%, thereby allowing efficient generation of rAAV vectors. Up to 10(13) rAAV particles and, more importantly, up to 10(11) infectious particles were generated from a 2-L bioreactor culture. The suspension-transfection strategy of this study facilitates the homogeneous preparation of rAAV at a large scale, and holds further potential as the basis for establishing a manufacturing process in a larger bioreactor. 相似文献
20.
We have evaluated the ectopic new bone formation effects of CPC (calcium phosphate cement) seeded with pBMP‐2 (plasmids containing bone morphogenetic protein‐2 gene) transfected canine bMSCs (bone marrow stromal cells) mediated by a non‐viral PEI (polyethylenimine) derivative (GenEscort? II) in nude mice. Canine bMSCs were transfected with pBMP‐2 or pEGFP (plasmids containing enhanced green fluorescent protein gene) mediated by GenEscort? II in vitro, and the osteoblastic differentiation was explored by ALP (alkaline phosphatase) staining, ARS (alizarin red S) staining and RT—qPCR (real‐time quantitative PCR) analysis. Ectopic bone formation effects of CPC/pBMP‐2 transfected bMSCs were evaluated and compared with CPC/pEGFP transfected bMSCs or CPC/untransfected bMSCs through histological, histomorphological and immunohistochemical analysis 8 and 12 weeks post‐operation in nude mice. Transfection efficiency was up ～35% as demonstrated by EGFP (enhanced green fluorescent protein) expression. ALP and ARS staining were stronger with pBMP‐2 gene transfection, and mRNA expression of BMP‐2 (bone morphogenetic protein‐2), Col 1 (collagen 1) and OCN (osteocalcin) in pBMP‐2 group was significantly up‐regulated at 6 and 9 days. Significantly higher NBV (new bone volume) was achieved in pBMP‐2 group than in the control groups at 8 and 12 weeks (P<0.05). In addition, immunohistochemical analysis indicated higher OCN expression in pBMP‐2 group (P<0.01). We conclude that CPC seeded with pBMP‐2 transfected bMSCs mediated by GenEscort? II could enhance ectopic new bone formation in nude mice, suggesting that GenEscort? II mediated pBMP‐2 gene transfer is an effective non‐viral method and CPC is a suitable scaffold for gene enhanced bone tissue engineering. 相似文献