scholarly journals Comparative Analysis of the Immunogenic Activity of the Plague Vaccine Depending on the Growing Medium

Author(s):  
S. E. Gostishcheva ◽  
N. V. Abzaeva ◽  
E. L. Rakitina ◽  
D. G. Ponomarenko ◽  
M. V. Kostyuchenko ◽  
...  

The aim was to carry out a comparative analysis of the immunogenic activity of the live plague vaccine obtained on various nutrient media.Materials and methods. The subject of the study was the blood of outbred white mice immunized with a series of live plague vaccine based on Yersinia pestis EV NIIEG strain, produced using experimental and regulated nutrient media. The immunogenic activity of vaccines was studied through flow cytometry. The intensity of antigen-reactivity of lymphocytes was determined in cell tests in vitro, analyzing the early activation marker CD25+ . For the specific activation of lymphocytes, a complex of water-soluble antigens of the plague microbe was used. To identify the interdependence between the presence of protective anti-plague immunity and the level of CD 25+ expression intensity, the ED50 of the series under study was determined by the standard method.Results and discussion. A comparative analysis of the immunogenic activity of the live plague vaccine obtained on the experimental nutrient medium with the vaccine produced on Hottinger’s agar has been performed. When animals were immunized with doses of 4·103 , 2·104 and 1·105 live microbial cells (regulated doses), the highest level of expression of CD25 marker by lymphocytes was on the day 14, with a subsequent decrease on the day 21 after vaccination. When determining immunogenicity using the conventional method, a high degree of direct correlation between the number of surviving animals and an increase in the level of lymphocytes expressing markers of early activation has been established. Comparison has revealed the general pattern: when the lowest immunizing dose (8·102 ) was administered, activation of early immunity markers was not observed. In case of immunization with higher doses on days 7, 14 and 21, a proportional increase in the number of CD25-positive lymphocytes after stimulation with a specific antigen under in vitro conditions is detected in the blood of biomodels.

2019 ◽  
Vol 18 (1) ◽  
pp. 50-54
Author(s):  
S. E. Gostischeva ◽  
N. V. Abzaeva ◽  
E. L. Rakitina ◽  
D. G. Ponomarenko ◽  
M. V. Kostuchenko ◽  
...  

Research objective–studying of a possibility of application antigen – stimulated cellular in vitro tests and technology of the cytometric analysis for control of immunogene activity of batches of vaccine plague live.Materials and methods.As biomodels used white laboratory mice, immunized commercial medicine of vaccine of the plague NIIEG line, live from a strain of Yersinia pestis EV, in doses – 8 х 102, 4 х 103, 2 х 104 and 1 х 105 of living microbic cells. Blood for a research was taken from intact mice and on 7, 14 and 21 days after immunization. The intensity of an antigenreaktivnost of lymphocytes was defined in cellular in vitro tests, analyzing a marker of early activation (CD45+CD3+CD25+) of lymphocytes with use of the monoclonal antibodies conjugated from fluorokhroma. As specific antigen used a complex of water-soluble antigens of a plague microbe.Results.As a result of a research it is shown that at the animals vaccinated by doses 4 х 103 – 1 х 105 living microbic cells, the highest level of an expression activation marker lymphocytes at anti-gene stimulation of in vitro is registered on 14 days after immunization, at the same time the quantity of CD25 – positive lymphocytes are on average 6.8 times higher, than in control group. High degree of direct link (coefficient of correlation of r = 1,000) quantities of the survived animals with increase in level of lymphocytes, expressiruyushchy markers of early activation – CD25 is established.Conclusions.The offered technique can be used as the additional test when studying degree of immunogenicity of new (kandidatny) vaccines against plague.


Development ◽  
1975 ◽  
Vol 34 (3) ◽  
pp. 531-557
Author(s):  
A. T. Mikhailov ◽  
V. M. Barabanov

Water-soluble antigens of chick retina were investigated using rabbit antisera to total extract and to individual electrophoretic fractions of retinal extract by methods of immunoelectrophoresis and Ouchterlony precipitation test. In the retina of the adult chick six serum and eleven tissue antigens were demonstrated. The tissue antigens of the retina comprised one organ-specific antigen and ten inter-organ antigens which were characterized by nonuniform distribution in tissues and organs of adult chick. Three antigens out of these were found only in tissues of the eye (retina, iris) and in the brain — inter-organ antigens of ‘narrow’ specificity. The other seven inter-organ antigens were found in tissues of brain and eye, as well as in various tissues and organs of hens — inter-organ antigens of ‘broad’ specificity. A high degree of antigen similarity between retina and iris was observed. Anti-retina sera in chick lens could detect only inter-organ antigens of ‘broad’ specificity. In the course of embryogenesis the first to appear in the developing retina were interorgan antigens of ‘broad’ specificity (on 3rd day of incubation). Formation of antigens of this group was completed by the 9th day of incubation. On the contrary, inter-organ antigens of ‘narrow’ specificity appeared later, in the period of histogenesis of retina (from 5 to 18 days of incubation). The organ-specific antigen of retina was found by 7th day of incubation. One of the inter-organ retinal antigens of ‘narrow’ specificity (retina-iris-brain) appeared in the developing chick brain at the same time as in retina — on 10th-11th day of incubation. Using the indirect immunofluorescence antibody technique this antigen was identified in the cytoplasm of retinal cells and brain neurones, but was not detected in the nerve fibres.


2021 ◽  
Vol 66 (7) ◽  
pp. 438-447
Author(s):  
Elena Vladimirovna Detusheva ◽  
O. N. Ershova ◽  
N. K. Fursova

The in vitro antibacterial activity of 11 commercial disinfectant preparations and 8 antiseptics against 10 strains of the bacteria Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloaceae and Providencia stuartii obtained from international collections and isolated from neuroresuscitation patients in Moscow in 2018 was studied. The sensitivity of planktonic cultures to the preparations was determined by the method of serial dilutions in broth and the spot method on solid nutrient media, the sensitivity of biofilms by the applicator method. A general pattern was revealed: the level of sensitivity to tested disinfectants in clinical strains was lower than in reference strains. It was found that the disinfectants «Mikrobak-Forte», «SAT-22», «Neobak-Oksi» at the concentrations recommended by the manufacturers were effective against bacteria of all test strains, both in the plankton state and in the form of biofilms. On the contrary, the disinfectant preparations «Biodez-Optima», «Biodez-Extra DVU», «Novodez-Aktiv», «Triosept-Oksi», «Tristel Fusion for Surfaces», «Effect-Forte Plus», «Lactic-Oxy» did not have sufficient effectiveness in the concentrations recommended by the manufacturers, therefore it is proposed to use these drugs in higher concentrations. It was found that the disinfectant «Biodez-Extra DVU» is able to inhibit the growth of biofilms of bacteria of the species K. pneumoniae. The ability to suppress the growth of bacterial biofilms of K. pneumoniae, A. baumannii, P. aeruginosa was revealed for the «Triestel Fusion for surfaces disinfectant». The bacteria of all used test strains in the planktonic state were sensitive to all tested antiseptic preparations. However, the biofilms of the clinical strains of P. aeruginosa and P. stuartii. possessed resistance to the antiseptics «Octenidol», «Octenisept», «Miramistin», «Hexoral». Our studies indicate the need for sensitivity analysis of antibacterial drugs in representatives of hospital pathogens, including the modeling of bacterial biofilms, which is a very relevant and important scientific direction, necessary to improve the control of nosocomial infections in the Russian Federation.


Author(s):  
Mashkura Ashrafi ◽  
Jakir Ahmed Chowdhury ◽  
Md Selim Reza

Capsules of different formulations were prepared by using a hydrophilic polymer, xanthan gum and a filler Ludipress. Metformin hydrochloride, which is an anti-diabetic agent, was used as a model drug here with the aim to formulate sustained release capsules. In the first 6 formulations, metformin hydrochloride and xanthan gum were used in different ratio. Later, Ludipress was added to the formulations in a percentage of 8% to 41%. The total procedure was carried out by physical mixing of the ingredients and filling in capsule shells of size ‘1’. As metformin hydrochloride is a highly water soluble drug, the dissolution test was done in 250 ml distilled water in a thermal shaker (Memmert) with a shaking speed of 50 rpm at 370C &plusmn 0.50C for 6 hours. After the dissolution, the data were treated with different kinetic models. The results found from the graphs and data show that the formulations follow the Higuchian release pattern as they showed correlation coefficients greater than 0.99 and the sustaining effect of the formulations was very high when the xanthan gum was used in a very high ratio with the drug. It was also investigated that the Ludipress extended the sustaining effect of the formulation to some extent. But after a certain period, Ludipress did not show any significant effect as the pores made by the xanthan gum network were already blocked. It is found here that when the metformin hydrochloride and the xanthan gum ratio was 1:1, showed a high percentage of drug release, i.e. 91.80% of drug was released after 6 hours. But With a xanthan gum and metformin hydrochloride ratio of 6:1, a very slow release of the drug was obtained. Only 66.68% of the drug was released after 6 hours. The percent loading in this case was 14%. Again, when Ludipress was used in high ratio, it was found to retard the release rate more prominently. Key words: Metformin Hydrochloride, Xanthan Gum, Controlled release capsule Dhaka Univ. J. Pharm. Sci. Vol.4(1) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website


Author(s):  
Lê Thanh Long ◽  
Nguyễn Văn Toản ◽  
Nguyễn Văn Huế ◽  
Trang Sĩ Trung ◽  
Vũ Ngọc Bội

Chủng D1 phân lập từ các mẫu chuối có vết bệnh thán thư điển hình được sử dụng để nghiên cứu khả năng kháng nấm của chitosan hoà tan trong nước (Water-soluble chitosan_WSC) ở điều kiện in vitro. Kết quả phân tích trình tự gen mã hoá 28S rRNA của chủng D1 cho thấy tương đồng trình tự cao với các trình tự tương ứng của loài Colletotrichum musae và được ký hiệu là Colletotrichum musae D1. Kết quả các thí nghiệm đều cho thấy C. musae D1 rất nhạy cảm với WSC, hiệu lực ức chế tăng khi tăng nồng độ WSC xử lý ở điều kiện in vitro. Trên môi trường PDA, nồng độ 1,6% WSC ức chế hoàn toàn sự sinh trưởng của sợi nấm C. musae D1, nồng độ ức chế 50% (PIRG50) và nồng độ ức chế tối thiểu 90% (MIC90) tương ứng với nồng độ WSC 0,28% và 0,88%. Trong môi trường PDB, giá trị IC50 và MIC90 tương ứng là 0,11% và 0,43% và sự phát triển của sợi nấm C. musae D1 bị ức chế hoàn toàn ở nồng độ 0,8%. WSC không chỉ ức chế sự nảy mầm mà còn gây biến đổi bất thường bào tử nấm khi quan sát trên kính hiển vi.


Growth regulators, phytohormones, both natural and artificial, are the main means to control plant ontogenesis. They are involved in regulating the processes of cell differentiation and cell divisions, the formation of tissues and organs, the changes in the rate of growth and development, the duration of the certain stages of ontogenesis. The main classes of phytohormones used in plant biotechnology, in particular, in the induction of haploid structures, are auxins and cytokinins. The mechanism of action of phytohormones on a cell is rather complicated and may have a different character. Understanding the characteristics of the action of phytohormones is complicated by the fact that the system of hormonal regulation of plant life is multicomponent. This is manifested in the fact that the same physiological process is most often influenced not by one, but by several phytohormones, covering a wide range of aspects of cell metabolism. In connection with the foregoing, the purpose of our work was to test a set of nutrient media with different basic composition and different proportions of phytohormones to determine the patterns of their influence on the processes of haploid structure induction in rape anther culture using accessions, developed at the Institute of Oilseed Crops NAAS. The material used was two accessions of winter rapeseed (No. 1 and No. 2) and one sample of spring rapeseed, provided by the Rapeseed Breeding laboratory of the Institute of Oilseed Crops. Incised inflorescences were kept against the background of low temperature of 6–8 ° C for several days, and then, under aseptic conditions, anthers with unripe pollen grains were isolated and planted on nutrient media differing in both basic mineral composition and content of phytohormones. MS (Murashige & Skoog 1962) and B5 (Gamborg et al 1968) media were used as basic media. Phytohormones were added to the basic media in various combinations – BA, 2,4-D, NAA at the concentrations of 0.1-0.6 mg/l. In each treatment up to 300 anthers were cultivated. Differences between treatments were evaluated using standard t-test. Studies have shown that in the anther culture of rapeseed on the tested nutrient media, morphogenic structures of different types (embryoids and callus) were originated. Synthetic auxin 2,4-D, regardless of the composition of the basic medium, caused the formation of structures of both types, though with a low frequency. Phytohormone BA of the cytokinin type had a similar effect. In this case, the frequency of structures was slightly higher, and the developed structures were represented mainly by embryoids. The joint action of cytokinin and auxin was the most favorable for the initiation of morphogenic structures. Such combination of phytohormones caused the formation of these structures with a frequency of 24.5-14.7% in the studied genotypes of winter rape. A similar effect of phytohormones on the induction and development of morphogenic structures was also observed in spring rape. In this case, a single basic MS medium was used. The experiment included treatments where phytohormones were absent (control), as well as various combinations of auxin and cytokinin. In the control treatment, the formation of new structures was not noted. In treatments with phytohormones, in addition to the medium with the combination of auxin and cytokinin, the medium in which only cytokinin was present was also rather effective. The treatment in which the action of auxin 2,4-D was combined with the action of another auxin, NAA, turned out to be practically ineffective. Thus, it was found that for the induction of morphogenic structures from microspores in rape anther culture of the tested genotypes, the combination of cytokinin with auxin, or the use of only single cytokinin BA without other phytohormones, had the most positive effect.


Author(s):  
Venu Madhav K ◽  
Somnath De ◽  
Chandra Shekar Bonagiri ◽  
Sridhar Babu Gummadi

Fenofibrate (FN) is used in the treatment of hypercholesterolemia. It shows poor dissolution and poor oral bioavailability after oral administration due to high liphophilicity and low aqueous solubility. Hence, solid dispersions (SDs) of FN (FN-SDs) were develop that might enhance the dissolution and subsequently oral bioavailability. FN-SDs were prepared by solvent casting method using different carriers (PEG 4000, PEG 6000, β cyclodextrin and HP β cyclodextrin) in different proportions (0.25%, 0.5%, 0.75% and 1% w/v). FN-SDs were evaluated solubility, assay and in vitro release studies for the optimization of SD formulation. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) analysis was performed for crystalline and morphology analysis, respectively. Further, optimized FN-SD formulation evaluated for pharmacokinetic performance in Wistar rats, in vivo in comparison with FN suspension.  From the results, FN-SD3 and FN-SD6 have showed 102.9 ±1.3% and 105.5±3.1% drug release, respectively in 2 h. DSC and PXRD studies revealed that conversion of crystalline to amorphous nature of FN from FT-SD formulation. SEM studies revealed the change in the orientation of FN when incorporated in SDs. The oral bioavailability FN-SD3 and FN-SD6 formulations exhibited 2.5-folds and 3.1-folds improvement when compared to FN suspension as control. Overall, SD of FN could be considered as an alternative dosage form for the enhancement of oral delivery of poorly water-soluble FN.


Author(s):  
Prakash Goudanavar ◽  
Ankit Acharya ◽  
Vinay C.H

Administration of an antiviral drug, acyclovir via the oral route leads to low and variable bioavailability (15-30%). Therefore, this research work was aimed to enhance bioavailability of acyclovir by nanocrystallization technique. The drug nanocrystals were prepared by anti-solvent precipitation method in which different stabilizers were used. The formed nanocrystals are subjected to biopharmaceutical characterization including solubility, particle size and in-vitro release. SEM studies showed nano-crystals were crystalline nature with sharp peaks. The formulated drug nanocrystals were found to be in the range of 600-900nm and formulations NC7 and NC8 showed marked improvement in dissolution velocity when compared to pure drug, thus providing greater bioavailability. FT-IR and DSC studies revealed the absence of any chemical interaction between drug and polymers used. 


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