Publications by authors named "A Tsertsvadze"

69 Publications

FORMULATION THERMORESPONSIVE NANOCOMPOSITE HYDROGELWITH EMBEDDED PLGA NANOPARTICLES CONTAINING CYTOTOXIC AGENT.

Georgian Med News 2021 Mar(312):133-138

Tbilisi State Medical University, Faculty of Pharmacy, 1Department of Pharmaceutical Technology; Georgia.

The aim of the study was to develop and characterize the nanocomposite in-situ hydrogel as local drug delivery system of cytotoxic agent. In-situ hydrogel consisting of 15% thermosensitive (Poloxamer 407) and 1% mucoadhesive (sodium alginate) polymers was selected as the optimal formulation by the conducted studies. The influence of nanoparticle concentration on gelation time and temperature has been experimentally established. As a result, the optimum concentration of nanoparticles (5%) is selected, which does not alter the gel forming process. The resulting nanocomposite hydrogel was characterized through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), rotational viscometer (LVDV-1T). FT-IR spectra confirmed the PLGA nanoparticles presence within the hydrogel matrix through the absorption peak located at 1750 cm-1. SEM images allowed observing the nanoparticles to be homogenously dispersed. The release pattern of the active substance from the nanocomposite hydrogel is following: at 72 h, 64% and 78% of the active substance were released into the phosphate buffer and cell culture area, respectively. Irritation test on hen's egg model revealed that formulated nanocomposite hydrogel did not show damage of vascular system.
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March 2021

BIOPHARMACEUTICAL UNDERSTANDING OF FORMULATION PREPARATION VARIABILITY OF PLGA NANOPARTICLES LOADED WITH ERYSIMUM EXTRACT.

Georgian Med News 2021 Feb(311):173-177

Tbilisi State Medical University, Faculty of Pharmacy, 1Department of Pharmaceutical Technology; Faculty of Pharmacy, 2Direction of Pharmacognosy and pharmaceutical botany, Georgia.

The purpose of this study was to evaluate effect of process and formulation variables on the preparation of Erysimum extract loaded PLGA nanoparticles. The influence of the various biopharmaceutical factors such as type of organic solvent, type and concentration of surfactant, polymer concentration in the organic phase, ratio of organic phase and water phase were studied. Modified emulsification solvent evaporation method was used for preparation of nanoparticles. Based on the performed experiments optimal formulation of nanocomposite is suggested. Nanoparticle size, size distribution and entrapment efficiency were determined. Among five non-ionic surfactants polyvinyl alcohol provided more stable nanocomposite. Influence mechanisms of different surfactants on nanoparticle formation are provided. Water miscible organic solvent, acetone obtained 232 nm nanoparticles with improved size distribution. Entrapment efficiency was increased to 73% by reducing ratio of organic and water phases. Based on experiments nanoparticles with stable, reproducible properties are fabricated.
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February 2021

FORMULATION OF BIODEGRADABLE POLYMERIC NANOPARTICLES CONTAINING CYTOTOXIC SUBSTANCE OF PLANT ORIGIN.

Georgian Med News 2020 Feb(299):137-142

Tbilisi State Medical University, 1Department of Pharmaceutical Technology, Georgia.

Formulation of novel drug delivery system is one of the approaches for improvement of pharmacological activity of drugs. This implies encapsulation of the API into the biocompatible polymeric material. Objective of the research was formulation of biodegradable amino acid based polyesteramide nanoparticles composing cytotoxic substance of plant origin. Research materials and methods: biodegradable polyesteramide (PEA), alkaloids from Vinca Minor, surfactants (Tween 80, polyvinyl pirolidone, polyvinyl alcohol, Poloxamer 188). NPs size (mean particle diameter) and size distribution (polydispersity index, PDI), and zeta-potential (ZP) were measured by dynamic light scattering (DLS) using a Zetasizer Nano ZS (Malvern Instruments, U.K.) at 25°C, UV spectrophotometer was used for %EE study. Amino acid based PEA particles were fabricated by the modified emulsification method. Based on the studies optimal composition and fabrication condition of PEA NPs was determined. The conditions of the NPs fabrication were as follows: the O/W ratio: 1:10; the solvent: DMSO; polymer concentration in the organic phase: 50.0 mg/mL; surfactants (PVA) concentration in aqueous phase 0.5%,the stirring rate: 1000 rpm. The influence of the various factors such as organic solvents, surfactants, as well as a polymer concentration in the organic phase,surfactant concentration in the aqueous phase,the organic/water phase ratio on the NPs fabrication was studied.The NPs were characterized by size (mean particle diameter & size distribution (polydispersity index, PDI), and zeta-potential (ZP). Increase concentration of the surfactant (polyvinyl alcohol) from 0.1% to 0.5% decrease average particle size from 568±63 to 169±1.66 respectively. EE% was obtained to be around 50%.
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February 2020

Identifying latent tuberculosis in high-risk populations: systematic review and meta-analysis of test accuracy.

Int J Tuberc Lung Dis 2019 11;23(11):1178-1190

Warwick Evidence, Warwick Medical School, University of Warwick, Coventry.

The relative accuracy of interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST) in identifying latent tuberculosis infection (LTBI) is uncertain. To perform a systematic review and meta-analysis to compare the sensitivity and specificity of IGRAs and TST for the prediction of progression to clinical tuberculosis (TB). We searched electronic databases (e.g., MEDLINE and EMBASE) from December 2009 to September 2018 for prospective studies that followed up individuals who had undergone testing with commercial IGRAs and/or TST but had not received treatment based on the test result. The sensitivity and specificity estimates were pooled using a Bayesian bivariate random-effects model. Twenty-five studies, mostly with moderate to high risk of bias and a mean follow-up time ranging from 1 to 5 years were included. TST (10-15 mm) tended to have lower sensitivity and higher specificity than QuantiFERON Gold In-Tube, T-SPOT. and TST (5 mm). The evidence did not indicate that any test outperformed the others due to wide and overlapping 95% credible intervals. The evidence following individuals who had undergone testing for LTBI and had progressed to clinical TB is sparse. We did not find that IGRAs were superior to TST or vice versa; however, as our findings are based on a small number of studies with methodological limitations and great uncertainty around the pooled estimates, the results should be interpreted with caution.
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http://dx.doi.org/10.5588/ijtld.18.0743DOI Listing
November 2019

Systematic review with meta-analysis of over 90 000 patients. Does fast-track review diagnose colorectal cancer earlier?

Aliment Pharmacol Ther 2019 08 8;50(4):348-372. Epub 2019 Jul 8.

University Hospitals Coventry and Warwickshire, Coventry, UK.

Background: National UK data on colorectal cancer (CRC) stage at diagnosis is incomplete. Site-specific fast-track (2-week wait) cancer data are not collected directly by NHS England. Policy making based on these data alone can lead to inaccuracy.

Aims: To review available data on key outcomes (cancer conversion rate and stage at diagnosis) for the UK's lower gastrointestinal 2-week wait pathway.

Methods: A comprehensive literature search was conducted between 2000 and 2017. Primary outcomes were cancer conversion rate and cancer stage at diagnosis. Results were expressed as proportions with 95% CIs. A random effects model was used for meta-analysis; heterogeneity was assessed by I .

Results: Of 95 papers reviewed, 49 were included in analysis with a total study population of 93,655. Cancer conversion rate was 7.7% (95% CI: 6.9-8.5). The proportion presenting at Dukes A = 11.2% (95% CI 7.4-15.6), B = 36.7% (95% CI 30.8-42.8), C = 35.7% (95% CI: 30.8-40.8) and D = 11.1% (95% CI 7.3-15.5). No colonic pathology was diagnosed in 54.6% (95% CI: 46.2-62.8).

Conclusions: Only 7.7% of patients referred by the 2-week wait pathway were found to have CRC. No beneficial effect on stage at diagnosis was found compared to non-2-week wait referral pathways. Over half of patients had no colonic pathology and detection of adenomas was very low. These results should prompt a reconsideration of the benefits of the 2-week wait pathway in CRC diagnosis and outcomes, with more focus on strategies to improve patient selection.
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http://dx.doi.org/10.1111/apt.15378DOI Listing
August 2019