RADIOIMMUNOASSAY FOR DETECTION OF ANTI-RINDERPEST ANTIBODIES IN CATTLES

Liquid Phase Radioimmunoassay (RIA) was developed to detect and measure anti-rinderpest immunoglobulins in field animals sera, within two hours. Rinderpest virus adapted on Vero cell line culture and antigen purified by treatment with Triton-Gentron 13 Butanol, and, labeled with I isotope, using chloramin T iodination method. Comparative studies for detecting anti-rinderpest immunoglobulin in 80 calves sera samples, using the developed assay in parallel with virus neutralization test (VNT). The study showed 58.75 % agreement between the two methods. However, 71 % of seven months old, non-vaccinated calves showed anti rinderpest antibodies in their sera, also 81 % of 10 months old vaccinated calves were developed antibodies in their blood. These results demonstrate the development of sensitive, specific and rapid quantitative / qualitative radioimmunoassay, necessary for screening the development of immunity against rinderpest in cattle.

IMMUNOGENICITY AND SAFETY OF INACTIVATED SARS-COV-2 VACCINE (VERO CELL), BBIBP-CORV (SINOPHARM); AN OBSERVATIONAL STUDY FROM PAKISTAN

Objective: To ascertain the immunogenicity and short-term safety of inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBPCorV (Sinopharm) in our setup. Study Design: Cross-sectional study. Place and Duration of Study: Combined Military Hospital Sialkot Pakistan, from Feb to Apr 2021. Methodology: A total of 227 health care workers (HCWs) between 18 to 59 years of age were included in the study. Two doses of Inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBP-CorV were administered to all individuals 21 days apart and they were monitored for any vaccine-related adverse reactions for 7 days after each dose. Neutralizing antibodies (NAbs) in study subjects were detected in three samples i.e. before 1st dose of vaccine, 21 days after 1st dose and 14 days after 2nd dose by Elecsys Anti- SARS-CoV-2 S (Roche Diagnostics). Results: Mean age of individuals in the study was 36.70 ± 18.08 years and most individuals were in the 31-45 years age group. Fatigue and drowsiness were the most common adverse effects experienced by study subjects after 1st and 2nd dose of the vaccine followed by malaise and headache. Only 42 (39%) individuals developed positive neutralizing antibody titers in a sample taken 21 days after 1st dose while all individuals except one (99%) developed positive neutralizing antibody titers in a sample taken 2 weeks after 2nd vaccine dose. Conclusion: Inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBP-CorV is safe and well-tolerated with very few adverse reactions. Immunogenicity was well achieved as the seroconversion rate was 99% two weeks after 2nd dose of the vaccine.

Biological Evaluation of Medical Devices in the Form of Suppositories for Rectal and Vaginal Use

Background. Programs of preclinical safety studies of the health care products depend on the regulatory status of the investigated products. The classification of such products, in particular suppositories for rectal and vaginal use, is a critical step of developing tactics for their biological evaluation. Adaptation of biological evaluation methods for the medical devices based on the combination of biologically active substances, as well as evaluation of the results of such studies is urgent task of biomedicine. Objective. To substantiate the regulatory status and to carry out a biological evaluation of medical devices in the form of vaginal suppositories based on octenidine dihydrochloride ("Prodexyn") and in the form of rectal suppositories based on Saw palmetto, Levisticum officinale and Calendula officinalis extracts ("Pravenor"). Methods. Biological evaluation was conducted according to the requirements of ISO 10993 standards using in vitro and in vivo biological test systems (cytotoxicity in cell culture and the MTT test, sensitizing and irritating effect in guinea pigs). Results. The cytotoxicity (СС50) of the medical device "Prodexyn" extract in Vero cell culture was 8.35 μg/ml calculated as octenidine dihydrochloride and 416.65 μg/ml calculated as dexpanthenol. "Pravenor" medical device was found to be non-toxic in Vero cell culture. According to the results of MMT assay CC50 for octenidine dihydrochloride was 1.67 μg/ml, and 83.33 μg/ml – for dexpanthenol. CC50 indicators calculated for the different active ingredients of the medical device "Pravenor" were the following: 50 mg/ml for the dwarf palm berries extract (Saw palmetto), 16.67 mg/ml for the lovage roots extract (Levisticum officinale), and 16.67 mg/ml for the calendula flowers extract (Calendula officinalis). No sensitizing or skin irritating effects were observed in guinea pigs. Conclusions. Biological evaluation of medical devices in the form of rectal suppositories "Pravenor" and vaginal suppositories "Prodexyn" performed using in vitro and in vivo biological systems. It was demonstrated an acceptable level of safety of the products. The MTT test was 5 times more sensitive than the Vero cell culture method in determination of cytotoxicity.

Pentosan polysulfate inhibits attachment and infection by SARS-CoV-2 in vitro: insights into structural requirements for binding.

Two years since the outbreak of the novel coronavirus SARS-CoV-2 pandemic, there remain few clinically effective drugs to complement vaccines. One is the anticoagulant, heparin, which in 2004 was found able to inhibit invasion of SARS CoV (CoV-1) and which has been employed during the current pandemic to prevent thromboembolic complications and moderate potentially damaging inflammation. Heparin has also been shown experimentally to inhibit SARS-CoV-2 attachment and infection in susceptible cells. At high therapeutic doses however, heparin increases the risk of bleeding and prolonged use can cause heparin-induced thrombocytopenia, a serious side-effect. One alternative, with structural similarities to heparin is the plant-derived, semi-synthetic polysaccharide, pentosan polysulfate (PPS). PPS is an established drug for the oral treatment of interstitial cystitis, is well-tolerated and exhibits weaker anticoagulant effects than heparin. In an established Vero cell model, PPS and its fractions of varying molecular weights, inhibited invasion by SARS-CoV-2. Intact PPS and its size-defined fractions were characterized by molecular weight distribution and chemical structure using NMR spectroscopy and LC-MS, then employed to explore the structural basis of interactions with SARS-CoV-2 spike protein receptor-binding domain (S1 RBD) and the inhibition of Vero cell invasion. PPS was as effective as unfractionated heparin, but more effective at inhibiting cell infection than low molecular weight heparin (on a weight/volume basis). Isothermal titration calorimetry and viral plaque-forming assays demonstrated size-dependent binding to S1 RBD and inhibition of Vero cell invasion, suggesting the potential application of PPS as a novel inhibitor of SARS-CoV-2 infection.

Characteristics and features of the formation of humoral immunity after immunization with Sputnik V and Vero Cell vaccines

The presented work contains an analysis of seroprevalence, tension, and duration of post-vaccination immunity to the SARS-CoV-2 coronavirus in the residents of the Republic of Belarus after immunization with two vaccine preparations available in the country: Sputnik V and Vero Cell.It was found that seroconversion after the injection of the Vero Cell vaccine occurred significantly later than after the Sputnik V vaccine (p < 0.001). Nevertheless, two-stage immunization with the vaccines provided a sufficiently high efficiency of the inoculated antibodies to the S protein of the COVID-19 pathogen: the proportion of seropositive persons reached 99.19 [96.89; 99.97] % for Sputnik V and 96.03 [90.81; 98.53] % for Vero Cell. The efficiency of antibody formation after immunization with the Vero Cell vaccine was lower in older persons (in the group > 65 years). The proportion of individuals with the highest IgG score for the SARS-CoV-2 S protein was higher after the Sputnik V administration compared to that in response to the Vero Cell vaccine (p < 0.05), and gradually decreased over time. However, no significant decrease in the level of seropositive individuals after 90 days from the start of immunization with the both vaccine preparations was detected. In COVID-19 survivors immunized with the Sputnik V vaccine, the quantitative indicators of post-vaccination antibodies reached their peak values after 1 dose of the vaccine. The obtained results complement the accumulated world science and practical information on the problem of the postvaccination immunity formation in the context of the use of different drugs against COVID-19.>< 0.001). Nevertheless, two-stage immunization with the vaccines provided a sufficiently high efficiency of the inoculated antibodies to the S protein of the COVID-19 pathogen: the proportion of seropositive persons reached 99.19 [96.89; 99.97] % for Sputnik V and 96.03 [90.81; 98.53] % for Vero Cell. The efficiency of antibody formation after immunization with the Vero Cell vaccine was lower in older persons (in the group > 65 years). The proportion of individuals with the highest IgG score for the SARS-CoV-2 S protein was higher after the Sputnik V administration compared to that in response to the Vero Cell vaccine (p < 0.05), and gradually decreased over time. However, no significant decrease in the level of seropositive individuals after 90 days from the start of immunization with the both vaccine preparations was detected. In COVID-19 survivors immunized with the Sputnik V vaccine, the quantitative indicators of post-vaccination antibodies reached their peak values after 1 dose of the vaccine.The obtained results complement the accumulated world science and practical information on the problem of the postvaccination immunity formation in the context of the use of different drugs against COVID-19.

5-Fluorouracil And Curcumin With Pectin Coating As a Treatment Regimen For Titanium Dioxide Induced Colon Cancer Model

Objective: Induction of colorectal cancer in Wister rats using titanium dioxide and dimethylhydrazine and treatment using the physical conjugate of 5-Fluorouracil and Curcumin, with a synergistic approach.Methods: Compatibility studies are evaluated by using FT-IR,Vero cell lines, and HCT-116 cell lines are used for evaluating the synergistic approach. This followed by induction using titanium dioxide and dimethylhydrazine in Wister rats and treatment using 5-Fluorouracil and Curcumin with pectin coating. Result: The samples were found to be compatible. The synergistic effect was obtained at 1:1, 1:2, 1:4, and 2:1 ratio, where 1:4 ratio shows a CI50 value of 0.896, selected further for the animal studies when studied in HCT 116 cell lines and found to be safe with Vero cell lines. Colorectal cancer was shown to be induced within 70 days of administration of titanium dioxide and dimethylhydrazine.1:4 ratio of 5-Fluorouracil and Curcumin (50:200) shows effective for the treatment of colorectal cancer within 28 days, proven using histopathology report, bodyweight analysis, and hematological reports.Conclusion: 5-Fluorouracil and curcumin (1:4) ratio works with a synergistic approach and was proven effective for the treatment of colorectal cancer induced bythe titanium dioxide and dimethylhydrazine.

Design, Synthesis and Biological Investigation of Some Novel Quinazolin-4(3H)-One Tethered 1, 3, 4-Thiadiazole-Thiol Motifs as Direct Enoyl Acyl Carrier Protein Reductase Inhibitors

Aims: In this study was two noteworthy pharmacophores quinazolin-4(3H)-one and 1,3,4-thiadiazole through methylene bridge were utilized to design, synthesize and characterize some novel 2-methyl quinazolin-4(3H)-one and 6-chloro-2-methyl quinazolin-4(3H)-one tethered S-substituted-1,3,4-thiadiazole-thiol structural analogs respectively as direct Mycobacterium Tuberculosis (MTB) enoyl acyl carrier protein reductase (InhA) inhibitors. Study Design: Design of structural analogs of quinazolin-4(3H)-one tethered 1,3,4-thiadiazole-thiol through methylene bridge by functional group modifications in core scaffold followed by computational studies to select promising compounds. Synthesis of some novel compounds, structural characterization and screening of biological activity of the same. Methodology: The molecular docking of designed compunds was carried out using schrodinger Glide XP into the active site of MTB InhA with protein data bank code (PDB ID: 2H7M). The interactions were evaluated based on the glide G score compared with reference standard isoniazid. Ten new compounds 7(A1-A10) were synthesized, characterized and screened for their in-vitro antitubercular activity by Microplate Almar Blue Assay (MABA) method followed by cytotoxicity evaluation of compounds 7A4 and 7A10 using Vero cell line. Results: All the designed compounds of series 7(A1-A10) had drug-like characteristics and were non-toxic to normal cells. In the molecular docking studies, compounds 7A4, 7A5, and 7A10 demonstrated strong binding affinity in the active region of MTB InhA protein and retained necessary amino acid interaction, similar to co-crystal 2H7M. Synthesized compounds 7(A1-A10) were found to have good antitubercular activity. Out of the series the compounds 7A4 and 7A10 were found to possess excellent antitubercular activity equipotent to reference standard streptomycin with minimum inhibitory concentration (MIC) value of 6.25µg/ml. The cytotoxic potential of compounds 7A4 and 7A10 showed remarkable selectivity index against Vero cell line. Conclusion: The findings of this study highlights the importance of tethering two pharmacophoric motifs in one compound to develop novel antitubercular agents that can be exploited as promising leads as direct InhA inhibitors.