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151.
Use of amplicon-6 vectors derived from human herpesvirus 6 for efficient expression of membrane-associated and -secreted proteins in T cells
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The composite amplicon-6 vectors, which are derived from human herpesvirus 6 (HHV-6), can target hematopoietic cells. In the presence of the respective helper viruses, the amplicons are replicated by the rolling circle mechanism, yielding defective genomes of overall size 135 to 150 kb, composed of multiple repeats of units, containing the viral DNA replication origin, packaging signals, and the selected transgene(s). We report the use of amplicon-6 vectors designed for transgene expression in T cells. The selected transgenes included the green fluorescent protein marker, the herpes simplex virus type 1 glycoprotein D (gD), and the gD gene deleted in the transmembrane region (gDsec). The vectors were tested after electroporation and passage in T cells with or without helper HHV-6A superinfections. The results were as follows. (i)The vectors could be passaged both as cell-associated and as cell-free secreted virions infectious to new cells. (ii)The intact gD accumulated at the cell surface, whereas the gDsec was dispersed at internal locations of the cells or was secreted into the medium. (iii)Analyses of amplicon-6-gD expression by flow cytometry have shown significant expression in cultures with reiterated amplicons and helper viruses. The vector has spread to >60% of the cells, and the efficiency of expression per cell increased 15-fold, most likely due to the presence of concatemeric amplicon repeats. Current studies are designed to test whether amplicon-6 vectors can be used for gene therapy in lymphocytes and whether amplicon-6 vectors expressed in T cells and dendritic cells can induce strong cellular and humoral immune responses. 相似文献
152.
153.
Hydrogels present an attractive alternative to nanoscale block copolymer aggregates and microscale resin beads as potential asystemic serum cholesterol reduction materials. Not only would the oral delivery of these materials be more pleasant than the sand-like bile salt anion sequestrant beads but also the hydrogel preparation is much simpler than the copolymer aggregate analogues [Cameron, N. S.; Eisenberg, A.; Brown, G. R. Biomacromolecules 2002, 3, 116-123. Cameron, N. S.; Eisenberg, A.; Brown, G. R. Biomacromolecules 2002, 3, 124-132]. Our goal was to explore these materials building on our experience with bulk resins and self-assembled copolymers. In this paper, following a brief introduction to hydrogels and their application to hypercholesterolemia, the synthesis, characterization, and preliminary glycocholate binding properties of poly(N,N,N-trimethylammoniumalkyl acrylamide chloride)gel are presented [Cameron, N. S.; Eisenberg, A.; Brown, G. R. Polym. Preprints 2002, 43, 771-772]. 相似文献
154.
Adi A. Garfunkel Joseph L. Shanfeld T. N. Harris 《Cancer immunology, immunotherapy : CII》1980,9(1-2):129-136
Summary In Balb/c plasmacytoma cells (MOPC 315) the synthesis and secretion of IgA in vitro was suppressed by prior incubation of the tumor cells with anti-Balb/c alloantibody. In tumor cells so treated, the levels of cyclic AMP were found to be increased. The alloantibody, either as alloantiserum or ascitic fluid globulins from allogeneic strains of mice immunized with spleen cells, had been differentially absorbed with Balb/c spleen cells. Such absorption reduces the cytotoxic antibody effect to below detectable levels, as measured by Trypan Blue exclusion, but permits retention of substantial levels of the suppressive antibody effect. The range of dilutions of alloantibody causing the increase in cAMP corresponded with those that caused suppression of IgA secretion. When tumor cells were exposed to agents that increased the level of cAMP either endogenously or exogenously, suppression of secretion of IgA was found, similar to that caused by the alloantibody. When submaximal concentrations of suppressive antibody were combined with submaximal levels of the cAMP-increasing agents greater degrees of suppression were found, suggesting an additive effect. No cytotoxic effect on these tumor cells, as indicated by Trypan Blue exclusion, was caused by these cAMP-increasing agents at the concentrations shown, either alone or in combination with the suppressive antibody. 相似文献
155.
Lianna Poghosyan Hanna Koch Adi Lavy Jeroen Frank Maartje A.H.J. van Kessel Mike S.M. Jetten Jillian F. Banfield Sebastian Lücker 《Environmental microbiology》2019,21(10):3627-3637
The recently discovered comammox process encompasses both nitrification steps, the aerobic oxidation of ammonia and nitrite, in a single organism. All known comammox bacteria are affiliated with Nitrospira sublineage II and can be grouped into two distinct clades, referred to as A and B, based on ammonia monooxygenase phylogeny. In this study, we report high-quality draft genomes of two novel comammox Nitrospira from the terrestrial subsurface, representing one clade A and one clade B comammox organism. The two metagenome-assembled genomes were compared with other representatives of Nitrospira sublineage II, including both canonical and comammox Nitrospira. Phylogenomic analyses confirmed the affiliation of the two novel Nitrospira with comammox clades A and B respectively. Based on phylogenetic distance and pairwise average nucleotide identity values, both comammox Nitrospira were classified as novel species. Genomic comparison revealed high conservation of key metabolic features in sublineage II Nitrospira, including respiratory complexes I–V and the machineries for nitrite oxidation and carbon fixation via the reductive tricarboxylic acid cycle. In addition, the presence of the enzymatic repertoire for formate and hydrogen oxidation in the Rifle clades A and B comammox genomes, respectively, suggest a broader distribution of these metabolic features than previously anticipated. 相似文献
156.
Ari Fahrial Syam Muhammad Miftahussurur Dadang Makmun Iswan Abbas Nusi Lukman Hakim Zain Zulkhairi Fardah Akil Willi Brodus Uswan David Simanjuntak Tomohisa Uchida Pangestu Adi Amanda Pitarini Utari Yudith Annisa Ayu Rezkitha Phawinee Subsomwong Nasronudin Rumiko Suzuki Yoshio Yamaoka 《PloS one》2015,10(11)
The prevalence of Helicobacter pylori infection in Indonesia is still controversial and mainly investigated in the largest ethnic group, Javanese. We examined the prevalence of H. pylori infection using four different tests including culture, histology confirmed by immunohistochemistry and rapid urease test. We also analyzed risk factors associated with H. pylori infection in five largest islands in Indonesia. From January 2014–February 2015 we consecutively recruited a total of 267 patients with dyspeptic symptoms in Java, Papua, Sulawesi, Borneo and Sumatera Island. Overall, the prevalence of H. pylori infection was 22.1% (59/267). Papuan, Batak and Buginese ethnics had higher risk for H. pylori infection than Javanese, Dayak and Chinese ethnics (OR = 30.57, 6.31, 4.95; OR = 28.39, 5.81, 4.61 and OR = 23.23, 4.76, 3.77, respectively, P <0.05). The sensitivity and specificity for RUT and culture were 90.2%, 92.9% and 80.5%, 98.2%, respectively. The patients aged 50–59 years group had significantly higher H. pylori infection than 30–39 years group (OR 2.98, P = 0.05). Protestant had significantly higher H. pylori infection rate than that among Catholic (OR 4.42, P = 0.008). It was also significantly lower among peoples who used tap water as source of drinking water than from Wells/river (OR 9.67, P = 0.03). However only ethnics as become independent risk factors for H. pylori infection. Although we confirmed low prevalence of H. pylori in Javanese; predominant ethnic in Indonesia, several ethnic groups had higher risk of H. pylori infection. The age, religion and water source may implicate as a risk factor for H. pylori infection in Indonesia. 相似文献
157.
Fen Liu Dilare Adi Xiang Xie Xiao-Mei Li Zhen-Yan Fu Chun-Fang Shan Ying Huang Bang-Dang Chen Min-Tao Gai Xiao-Ming Gao Yi-Tong Ma Yi-Ning Yang 《PloS one》2015,10(12)
Objectives
Little is known about isolated diastolic hypertension (IDH) among different ethnicity groups. We aimed to investigate the prevalence and risk factors for IDH among the major ethnicity population i.e. Han, Uygur and Kazakh in Xinjiang, northwestern part of China.Methods
In total, 14,618 adult participants (7,799 males, 6,819 females) were recruited from the Cardiovascular Risk Survey conducted during 2007 and 2010. Blood pressure, body mass index and standard lipid profile and fasting glucose level from plasma were measured.Results
The overall prevalence of IDH was 10.8% in the Han, 4.5% in the Uygur and 8.7% in the Kazakh populations. When stratified by gender, IDH prevalence was 9.8% in men and 6.8% in women (P<0.001). The prevalence of IDH also varied significantly with age and it was highest in those aged 35–44 yrs old (9.7%) and lowest in those over 75 yrs old (4.1%, P<0.001). Multivariate logistic regression analysis showed that overweight (OR = 1.179, 95%CI: 1.015–1.369) or obesity (OR = 1.202, 95%CI: 1.015–1.424), smoking (OR = 1.362, 95%CI: 1.156–1.604) and high total cholesterol (TC) hyperlipidemia (OR = 1.237, 95%CI: 1.074–1.423) were significantly associated with a higher prevalence of IDH. Identified risk factors for IDH differed among ethnicity groups with male gender, young age (35–44 yrs old), more coffee or tea consumption and high TC hyperlipidemia in the Han; smoking and often coffee or tea consumption in the Uygur and male gender and overweight or obesity in the Kazakh populations.Conclusions
IDH prevalence in the Han population is higher than that in the Uygur and Kazak populations in Xinjiang, northwestern part of China. Male gender, middle age, overweight or obesity, smoking and high TC hyperlipidemia appear to be relevant risk factors of IDH in adults. Different ethnicity background had different sets of risk factors for IDH. 相似文献158.
Objective
International guidelines recommend dopamine or norepinephrine as first-line vasopressor agents in septic shock. Phenylephrine, epinephrine, vasopressin and terlipressin are considered second-line agents. Our objective was to assess the evidence for the efficiency and safety of all vasopressors in septic shock.Methods
Systematic review and meta-analysis. We searched electronic database of MEDLINE, CENTRAL, LILACS and conference proceedings up to June 2014. We included randomized controlled trials comparing different vasopressors for the treatment of adult patients with septic shock. Primary outcome was all-cause mortality. Other clinical and hemodynamic measurements were extracted as secondary outcomes. Risk ratios (RR) and mean differences with 95% confidence intervals (CI) were pooled.Results
Thirty-two trials (3,544 patients) were included. Compared to dopamine (866 patients, 450 events), norepinephrine (832 patients, 376 events) was associated with decreased all-cause mortality, RR 0.89 (95% CI 0.81-0.98), corresponding to an absolute risk reduction of 11% and number needed to treat of 9. Norepinephrine was associated with lower risk for major adverse events and cardiac arrhythmias compared to dopamine. No other mortality benefit was demonstrated for the comparisons of norepinephrine to epinephrine, phenylephrine and vasopressin / terlipressin. Hemodynamic data were similar between the different vasopressors, with some advantage for norepinephrine in central venous pressure, urinary output and blood lactate levels.Conclusions
Evidence suggests a survival benefit, better hemodynamic profile and reduced adverse events rate for norepinephrine over dopamine. Norepinephrine should be regarded as the first line vasopressor in the treatment of septic shock. 相似文献159.