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Theone C. Kon Adrian Onu Laurentiu Berbecila Emilia Lupulescu Alina Ghiorgisor Gideon F. Kersten Yi-Qing Cui Jean-Pierre Amorij Leo Van der Pol 《PloS one》2016,11(3)
The aim of this study was to evaluate the impact of different inactivation and splitting procedures on influenza vaccine product composition, stability and recovery to support transfer of process technology. Four split and two whole inactivated virus (WIV) influenza vaccine bulks were produced and compared with respect to release criteria, stability of the bulk and haemagglutinin recovery. One clarified harvest of influenza H3N2 A/Uruguay virus prepared on 25.000 fertilized eggs was divided equally over six downstream processes. The main unit operation for purification was sucrose gradient zonal ultracentrifugation. The inactivation of the virus was performed with either formaldehyde in phosphate buffer or with beta-propiolactone in citrate buffer. For splitting of the viral products in presence of Tween®, either Triton™ X-100 or di-ethyl-ether was used. Removal of ether was established by centrifugation and evaporation, whereas removal of Triton-X100 was performed by hydrophobic interaction chromatography. All products were sterile filtered and subjected to a 5 months real time stability study. In all processes, major product losses were measured after sterile filtration; with larger losses for split virus than for WIV. The beta-propiolactone inactivation on average resulted in higher recoveries compared to processes using formaldehyde inactivation. Especially ether split formaldehyde product showed low recovery and least stability over a period of five months. 相似文献
3.
A rapid method for cloning and sequencing variable-region genes of expressed immunoglobulins 总被引:9,自引:0,他引:9
A rapid procedure is described for cloning immunoglobulin V region genes from cells that express them. cDNA is synthesized from mRNA template using primers homologous to the immunoglobulin constant-region genes. Blunt-ended, double-stranded cDNA is obtained by sequential addition of enzymes to a single tube. The cDNA is inserted directly into the M13 vector, which is screened by plaque lifting for the presence of specific inserts. Screening probes can be generated from 32P-labeled single-stranded cDNAs generated from primers different from those used for cloning, or alternatively, from previously cloned V or C gene segments. The ease of cloning a cDNA V region is directly related to the abundance of Ig-specific mRNA within the cell of interest. This method minimizes the number of steps and the time needed to obtain accurate and complete sequences of any expressed Ig V region gene. 相似文献
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Changes in juxtaglomerular (JG; renin-containing) cells in experimental hydronephrosis 1 month after ureteral ligation were investigated with immunoelectron-microscopical techniques. Two types of granules, electron dense (D) and lucent (L), were observed. D type granules were labeled more intensely with gold particles than those of L type. Granules intermediate between D and L types and exocytosis of D types were observed. In the cells containing D types exclusively, gold particles were restricted to the granules, whereas in the cells containing both D and L type granules, the particles were scattered throughout the cytoplasmic cytosol. The authors discuss the mechanisms of renin release in JG cells. 相似文献
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The use of ethyl methanesulfonate for the induction of mutants inMycobacterium phlei PA 总被引:2,自引:0,他引:2
The mutagenic effect of ethyl methanesulfonate in a concentration of 0.2m on a prototrophic, acid-fast strainMycobacterium phlei PA was studied by following the induction of changes of three genetic markers: prototrophy to auxotrophy and sensitivity
to two antituberculosis drugs (INH and STM) to resistence. Ethylmethanesulfonate was found to be a very effective mutagen
in all three cases. Thirty auxotrophic strains were obtained, out of which eight exhibited a low frequency of spontaneous
reversions and could hence be used for further studies. Of the phenotypes induced the glycine− (serine−) type was most frequently isolated and represented more than half of all auxotrophs obtained. Requirements for lysine and
purines were also observed. The EMS treatment (1% survival of the basic suspension) resulted in a 74-fold increase of the
frequency of INH-resistant mutants and a frequency of STM-resistant mutants about 1.1/2 to almost 2 orders of magnitude higher
than the spontaneous values 相似文献
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Molecularly imprinted polymeric microbeads (MIPMs) were prepared by the suspension and modified suspension polymerization
methods using D-phenylalanine as the template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate
as the cross-linker, toluene as the porogen, polyvinyl alcohol as the stabilizer, and sodium dodecyl sulfate as the surfactant.
The addition of a surfactant to the conventional suspension polymerization mixture decreased the mean particle size of the
MIPMs and increased the adsorption selectivity. For the modified suspension polymerization method, the mean particle size
of the MIPMs was smaller than the particle size of MIPMs prepared via conventional suspension polymerization. Moreover, the
adsorption selectivity improved considerably compared to the adsorption selectivities of MIPs reported previously. 相似文献
10.
Saranya Limkaisang James Henry Cunnington Liew Kon Wui Baharuddin Salleh Yukio Sato Rangsi Divarangkoon Wanwisa Fangfuk Chaiwat To-anun Susumu Takamatsu 《Mycoscience》2006,47(6):327-335
To investigate the phylogenetic relationships among the powdery mildew fungi of some economically important tropical trees
belonging to Oidium subgenus Pseudoidium, we conducted molecular phylogenetic analyses using 30 DNA sequences of the rDNA internal transcribed spacer (ITS) regions
and 26 sequences of the domains D1 and D2 of the 28S rDNA obtained from the powdery mildews on Hevea brasiliensis (para rubber tree), Anacardium occidentale (cashew), Bixa orellana, Citrus spp., Mangifera indica (mango), and Acacia spp. The results indicate that the powdery mildew fungi isolated from these tropical trees are closely related to one another.
These powdery mildews are also closely related to E. alphitoides (including Erysiphe sp. on Quercus phillyraeoides). Because of the obligate biotrophic nature of the powdery mildew fungi, the relationship between powdery mildews and their
host plants is conservative. However, the present study suggests that a particular powdery mildew species has expanded its
host ranges on a wide range of the tropical trees. This article also suggests that a powdery mildew fungus distributed in
temperate regions of the Northern Hemisphere expanded its host ranges onto tropical plants and may be a good example of how
geographical and host range expansion has occurred in the Erysiphales. 相似文献