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1.
Int J Antimicrob Agents ; 63(2): 107074, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154660

RESUMO

Increasing HIV drug resistance is an important public health concern. The current study aimed to assess HIV drug resistance among people who live with HIV (PLWH) experiencing virological failure. Blood samples and epidemiological characteristics were collected in four Siberian regions from PLWH experiencing ART failure. Partial pol gene sequences were obtained for the study individuals. Drug resistance mutations (DRMs) were predicted using the Stanford HIVdb Program. The association of HIV DRM with epidemiological characteristics was estimated using logistic regression analysis. Further analysis was performed for children (0-14 y old) and adults (≥15 y old) separately. In total, 815 (89.4%) patients were included in the final dataset. Overall, 501 (61.5%) patients had DRM detected. NRTI DRM was more common in children, while NRTI+NNRTI DRM was more frequent in adults (P < 0.001). Krasnoyarsk region, male sex and high viral load were positively associated with the presence of DRM in adults, while higher CD4 cell count and PI/INSTI-based ART had a negative association. No association between epidemiological characteristics and DRM was identified in children. The remaining 38.5% of patients with virological failure had no DRM detected; those patients were likely to have insufficient ART adherence. Most (55.5%) patients had HIV CRF63_02A6, followed by sub-subtype A6 (39.2%). This study revealed poor ART adherence as a main factor driving ART failure among PLWH in the Siberian region. DRM was detected in over 60% of PLWH experiencing ART failure. The current results highlight an urgent need for the introduction of special programs focusing on ART adherence improvement.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adulto , Criança , Humanos , Masculino , HIV-1/genética , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Mutação , Carga Viral , Federação Russa/epidemiologia
2.
Front Microbiol ; 13: 946787, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118194

RESUMO

HIV-1 epidemic in Russia is one of the fastest growing in the world reaching 1.14 million people living with HIV-1 (PLWH) in 2021. Since mid-1990s, the HIV-1 epidemic in Russia has started to grow substantially due to the multiple HIV-1 outbreaks among persons who inject drugs (PWID) leading to expansion of the HIV-1 sub-subtype A6 (former Soviet Union (FSU) subtype A). In 2006, a local HIV-1 sub-epidemic caused by the distribution of novel genetic lineage CRF63_02A6 was identified in Siberia. In this study, we used a comprehensive dataset of CRF63_02A6 pol gene sequences to investigate the spatiotemporal dynamic of the HIV-1 CRF63_02A6 sub-epidemic. This study includes all the available CRF63_02A6 HIV-1 pol gene sequences from Los Alamos National Laboratory (LANL) HIV Sequence Database. The HIV-1 subtypes of those sequences were conferred using phylogenetic analysis, and two automated HIV-1 subtyping tools Stanford HIVdb Program and COMET. Ancestral state reconstruction and origin date were estimated using Nextstrain. Evolutionary rate and phylodynamic analysis were estimated using BEAST v 1.10.4. CRF63_02A6 was assigned for 872 pol gene sequences using phylogenetic analysis approach. Predominant number (n = 832; 95.4%) of those sequences were from Russia; the remaining 40 (4.6%) sequences were from countries of Central Asia. Out of 872 CRF63_02A6 sequences, the corresponding genetic variant was assigned for 75.7 and 79.8% of sequences by Stanford and COMET subtyping tools, respectively. Dated phylogenetic analysis of the CRF63_02A6 sequences showed that the virus most likely originated in Novosibirsk, Russia, in 2005. Over the last two decades CRF63_02A6 has been widely distributed across Russia and has been sporadically detected in countries of Central Asia. Introduction of new genetic variant into mature sub-subtype A6 and CRF02_AGFSU epidemics could promote the increase of viral genetic diversity and emergence of new recombinant forms. Further HIV-1 studies are needed due to a continuing rapid virus distribution. Also, the implementation of HIV-1 prevention programs is required to reduce HIV-1 transmission. This study also highlights the discrepancies in HIV-1 subtyping approaches. The reference lists of HIV-1 sequences implemented in widely used HIV-1 automated subtyping tools need to be updated to provide reliable results.

3.
Polymers (Basel) ; 14(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35160398

RESUMO

It has been shown that macromolecules of poly(methacryloyloxyethyl phosphorylcholine) can form hydrogen bonded interpolymer complexes with homo- and copolymers of carboxylic acids and with poly(vinylphosphonic) acid in aqueous solutions. Polarized luminescence and IR spectroscopy were applied in the investigation. Nanosecond relaxation times characterizing the mobility of the chain fragments for the initial luminescent labeled polymers were determined and their changes by a factor of 2-50 were established during the formation of an interpolymer complex. Hydrogen bonds play a dominant role in the formation of these complexes. Hydrophobic interactions serve as an additional stabilizing factor. It is established that poly(methacryloyloxyethyl phosphorylcholine)/poly(vinylphosphonic acid) complex forms a looser structure in comparison with those for polycarboxylic acids as result of electrostatic repulsion between charged groups.

4.
Polymers (Basel) ; 14(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35160579

RESUMO

Free radical copolymerization is used for the synthesis of novel water-soluble copolymers of vinylphosphonic acid with 2-deoxy-2-methacrylamido-D-glucose or 4-acryloylmorpholine, with varied compositions and molecular masses, as well as for the synthesis of copolymers of vinylphosphonic acid with acrylamide. The obtained copolymers contain 6-97 mol.% of vinylphosphonic acid units, and their molecular masses vary from 5 × 103 to 310 × 103. The monomer reactivity ratios of vinylphosphonic acid and 2-deoxy-2-methacrylamido-D-glucose in copolymerization are determined for the first time, and their values are 0.04 and 9.02, correspondingly. It is demonstrated that the synthesized copolymers form luminescent mixed-ligand complexes with Eu3+, thenoyltrifluoroacetone, and phenanthroline. The influence of the comonomer's nature on the intensity of the luminescence of complex solutions is revealed.

5.
Polymers (Basel) ; 13(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205969

RESUMO

N-vinylpyrrolidone-co-allylamine copolymers (VP-co-AA) containing iminodiacetic (IDA) chelation units were prepared in the range of molecular masses of the copolymers from 9000 to 30,000 Da depending on polymerization conditions. Non-radioactive organometallic species Re(CO)3+ were introduced into polymeric carriers under mild conditions; the prepared metal-polymeric complexes were characterized by IR, NMR, ESI-MS and HPLC. IR spectra data confirmed the coordination of M(CO)3+ moiety to the polymeric backbone via IDA chelation unit (appearance of characteristic fac-M(CO)3+ vibrations (2005, 1890 cm-1), as well as the appearance of group of signals in 1H NMR spectra, corresponding to those inequivalent to methylene protons CH2COO (dd, 4.2 ppm), coordinated to metal ions. The optimal conditions for labeling the PVP-co-AA-IDA copolymers with radioactive 99mTc(CO)3+ species were determined. The radiochemical yields reached 97%. The obtained radiolabeled polymers were stable in blood serum for 3 h. In vivo distribution experiments in intact animals showed the high primary accumulation of technetium-99m MPC (MM = 15,000 Da) in blood with subsequent excretion via the urinary tract.

6.
J Biotechnol ; 236: 78-87, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27531578

RESUMO

Creation of multifunctional nanoplatforms is one of the new approaches to complex treatment and diagnosis with the monitoring of the curative process. Inclusion of various components into the drug delivery system may reduce toxicity and enhance or modify the therapeutic effects of medicines. In particular, some properties of metal nanoparticles and nanoclusters provide the ability to create new systems for treatment and diagnosis of diseases, biocatalysis and imaging of objects. For example, the ability of metal nanoparticles to enhance the quantum yield of luminescence can be used in bioimaging and therapy. The aim of the research was to construct and examine a multicomponent system based on DNA-polycation compact structure with the inclusion of silver nanoparticles and luminescent dye as a model system for delivery of genes and drugs with the possibility of modification and enhancement of their action.


Assuntos
DNA/química , Sistemas de Liberação de Medicamentos/métodos , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Metacrilatos/química , Nanotecnologia/métodos , Nylons/química , Prata/química , Linhagem Celular Tumoral , DNA/farmacocinética , Corantes Fluorescentes/farmacocinética , Vetores Genéticos/genética , Vetores Genéticos/farmacocinética , Humanos , Prata/farmacocinética
7.
J Sep Sci ; 32(15-16): 2674-81, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19603391

RESUMO

LC on short monolithic columns (Convective Interaction Medium Disks) was applied to investigate several specially synthesized water soluble polycations of different charge type (primary, tertiary, quaternary amine), as well as a copolymer of neutral saccharide and cationic monomers, regarding their ability to form reversible complexes with DNA. For this purpose, two separation modes were used, namely, pseudo-affinity and cation-exchange chromatography. Synthetic polynucleotides, namely, polyriboadenylic acid (poly(rA)) and polyribocytidylic acid (poly(rC)), were used as approximate structural analogues of DNA. In first case, the hypothetical specific binding between dissolved polymers and polynucleotide (poly(rA) or poly(rC)), covalently attached to epoxy-bearing monolithic sorbent, has been studied and compared to the results obtained using cation exchange chromatography. Quantitative parameters of interactions between macromolecules were established using frontal elution method.


Assuntos
Cromatografia Líquida/instrumentação , Poliaminas/química , Polinucleotídeos/química , Cromatografia Líquida/métodos , Ligantes , Estrutura Molecular , Polieletrólitos , Polímeros/química
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