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1.
Viruses ; 16(5)2024 05 10.
Article En | MEDLINE | ID: mdl-38793640

The HIV-1 Rev protein expressed in the early stage of virus replication is involved in the nuclear export of some forms of virus RNA. Naturally occurring polymorphisms in the Rev protein could influence its activity. The association between the genetic features of different virus variants and HIV infection pathogenesis has been discussed for many years. In this study, Rev diversity among HIV-1 group M clades was analyzed to note the signatures that could influence Rev activity and, subsequently, clinical characteristics. From the Los Alamos HIV Sequence Database, 4962 Rev sequences were downloaded and 26 clades in HIV-1 group M were analyzed for amino acid changes, conservation in consensus sequences, and the presence of clade-specific amino acid substitutions (CSSs) and the Wu-Kabat protein variability coefficient (WK). Subtypes G, CRF 02_AG, B, and A1 showed the largest amino acid changes and diversity. The mean conservation of the Rev protein was 80.8%. In consensus sequences, signatures that could influence Rev activity were detected. In 15 out of 26 consensus sequences, an insertion associated with the reduced export activity of the Rev protein, 95QSQGTET96, was identified. A total of 32 CSSs were found in 16 clades, wherein A6 had the 41Q substitution in the functionally significant region of Rev. The high values of WK coefficient in sites 51 and 82, located on the Rev interaction surface, indicate the susceptibility of these positions to evolutionary replacements. Thus, the noted signatures require further investigation.


Genetic Variation , HIV Infections , HIV-1 , rev Gene Products, Human Immunodeficiency Virus , HIV-1/genetics , HIV-1/classification , rev Gene Products, Human Immunodeficiency Virus/genetics , rev Gene Products, Human Immunodeficiency Virus/metabolism , Humans , HIV Infections/virology , Phylogeny , Amino Acid Substitution , Amino Acid Sequence , Consensus Sequence
2.
Stem Cell Res ; 77: 103424, 2024 Jun.
Article En | MEDLINE | ID: mdl-38677032

Succinic Semialdehyde Dehydrogenase Deficiency (SSADHD) is an ultra-rare autosomal recessive neurometabolic disorder caused by ALDH5A1 mutations presenting with autism and epilepsy. Here, we report the generation and characterization of human induced pluripotent stem cells (hiPSCs) derived from fibroblasts of three unrelated SSADHD patients - one female and two males with the CRISPR-corrected isogenic controls. These individuals are clinically diagnosed and are being followed in a longitudinal clinical study.


Induced Pluripotent Stem Cells , Succinate-Semialdehyde Dehydrogenase , Humans , Induced Pluripotent Stem Cells/metabolism , Male , Female , Succinate-Semialdehyde Dehydrogenase/deficiency , Succinate-Semialdehyde Dehydrogenase/genetics , Succinate-Semialdehyde Dehydrogenase/metabolism , Amino Acid Metabolism, Inborn Errors/genetics , Amino Acid Metabolism, Inborn Errors/pathology , Cell Line , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , CRISPR-Cas Systems , Developmental Disabilities
3.
HIV Med ; 2024 Apr 07.
Article En | MEDLINE | ID: mdl-38584123

BACKGROUND: This study aimed to investigate mutations associated with, the causes of, and the conditions that contribute to HIV drug resistance (DR). This research provides crucial insights into the mechanisms through which HIV evades antiretroviral drugs and suggests strategies to counter this phenomenon. Our objective was to assess the prevalence and structure of DR in HIV-1 across various regions in Russia and identify the primary factors influencing the development of HIV DR. METHODS: The study used nucleotide sequences from the HIV-1 pol gene obtained from 1369 patients with a history of therapy and virological failure between 2005 and 2019 to analyze the frequency and structure of DR and the factors associated with it. RESULTS: The analysed HIV-1 genotypes included viruses resistant to nucleoside reverse transcriptase inhibitors (NRTIs; 11.8%), non-nucleoside reverse transcriptase inhibitors (NNRTIs; 6.4%), and NRTIs + NNRTIs (31.7%). The mutations M184V/I and G190A/S/E were the most prevalent, accounting for 54.5% and 26.6%, respectively. The dominance of multiple DR persisted throughout the entire observation period. The likelihood of encountering drug-resistant variants was increased among men, patients in the late stage of infection, and those with a viral load <30 000 RNA copies/mL. Injection drug use was not associated with DR. CONCLUSION: This study has yielded new insights into HIV DR in Russia, offering valuable information to identify clinical or programmatic events warranting closer attention and support.

4.
Viruses ; 15(11)2023 Nov 04.
Article En | MEDLINE | ID: mdl-38005889

Tat, the trans-activator of transcription, is a multifunctional HIV-1 protein that can induce chronic inflammation and the development of somatic diseases in HIV-infected patients. Natural polymorphisms in Tat can impact the propagation of the inflammatory signal. Currently, Tat is considered an object for creating new therapeutic agents. Therefore, the identification of Tat protein features in various HIV-1 variants is a relevant task. The purpose of the study was to characterize the genetic variations of Tat-A6 in virus variants circulating in the Moscow Region. The authors analyzed 252 clinical samples from people living with HIV (PLWH) with different stages of HIV infection. Nested PCR for two fragments (tat1, tat2) with subsequent sequencing, subtyping, and statistical analysis was conducted. The authors received 252 sequences for tat1 and 189 for tat2. HIV-1 sub-subtype A6 was identified in 250 samples. The received results indicated the features of Tat1-A6 in variants of viruses circulating in the Moscow Region. In PLWH with different stages of HIV infection, C31S in Tat1-A6 was detected with different occurrence rates. It was demonstrated that Tat2-A6, instead of a functional significant 78RGD80 motif, had a 78QRD80 motif. Herewith, G79R in Tat2-A6 was defined as characteristic amino acid substitution for sub-subtype A6. Tat2-A6 in variants of viruses circulating in the Moscow Region demonstrated high conservatism.


HIV Infections , HIV-1 , Humans , Gene Products, tat/metabolism , Moscow/epidemiology , HIV-1/genetics , HIV-1/metabolism , HIV Infections/epidemiology , Russia/epidemiology , tat Gene Products, Human Immunodeficiency Virus/genetics
5.
BMJ Glob Health ; 7(12)2022 12.
Article En | MEDLINE | ID: mdl-36524410

Inspired by the 2021 BMJ Global Health Editorial by Atkins et al on global health (GH) teaching during the COVID-19 pandemic, a group of GH students and recent graduates from around the world convened to discuss our experiences in GH education during multiple global crises. Through weekly meetings over the course of several months, we reflected on the impact the COVID-19 pandemic and broader systemic inequities and injustices in GH education and practice have had on us over the past 2 years. Despite our geographical and disciplinary diversity, our collective experience suggests that while the pandemic provided an opportunity for changing GH education, that opportunity was not seized by most of our institutions. In light of the mounting health crises that loom over our generation, emerging GH professionals have a unique role in critiquing, deconstructing and reconstructing GH education to better address the needs of our time. By using our experiences learning GH during the pandemic as an entry point, and by using this collective as an incubator for dialogue and re-imagination, we offer our insights outlining successes and barriers we have faced with GH and its education and training. Furthermore, we identify autonomous collectives as a potential viable alternative to encourage pluriversality of knowledge and action systems and to move beyond Western universalism that frames most of traditional academia.


COVID-19 , Global Health , Humans , Pandemics , Students , Health Education
6.
Front Psychiatry ; 13: 924956, 2022.
Article En | MEDLINE | ID: mdl-36405918

16p13.11 copy number variants (CNVs) have been associated with autism, schizophrenia, psychosis, intellectual disability, and epilepsy. The majority of 16p13.11 deletions or duplications occur within three well-defined intervals, and despite growing knowledge of the functions of individual genes within these intervals, the molecular mechanisms that underlie commonly observed clinical phenotypes remain largely unknown. Patient-derived, induced pluripotent stem cells (iPSCs) provide a platform for investigating the morphological, electrophysiological, and gene-expression changes that result from 16p13.11 CNVs in human-derived neurons. Patient derived iPSCs with varying sizes of 16p13.11 deletions and familial controls were differentiated into cortical neurons for phenotypic analysis. High-content imaging and morphological analysis of patient-derived neurons demonstrated an increase in neurite branching in patients compared with controls. Whole-transcriptome sequencing revealed expression level changes in neuron development and synaptic-related gene families, suggesting a defect in synapse formation. Subsequent quantification of synapse number demonstrated increased numbers of synapses on neurons derived from early-onset patients compared to controls. The identification of common phenotypes among neurons derived from patients with overlapping 16p13.11 deletions will further assist in ascertaining common pathways and targets that could be utilized for screening drug candidates. These studies can help to improve future treatment options and clinical outcomes for 16p13.11 deletion patients.

7.
Curr Protoc ; 2(10): e568, 2022 Oct.
Article En | MEDLINE | ID: mdl-36264199

Neuromesodermal progenitors represent a unique, bipotent population of progenitors residing in the tail bud of the developing embryo, which give rise to the caudal spinal cord cell types of neuroectodermal lineage as well as the adjacent paraxial somite cell types of mesodermal origin. With the advent of stem cell technologies, including induced pluripotent stem cells (iPSCs), the modeling of rare genetic disorders can be accomplished in vitro to interrogate cell-type specific pathological mechanisms in human patient conditions. Stem cell-derived models of neuromesodermal progenitors have been accomplished by several developmental biology groups; however, most employ a 2D monolayer format that does not fully reflect the complexity of cellular differentiation in the developing embryo. This article presents a dynamic 3D combinatorial method to generate robust populations of human pluripotent stem cell-derived neuromesodermal organoids with multi-cellular fates and regional identities. By utilizing a dynamic 3D suspension format for the differentiation process, the organoids differentiated by following this protocol display a hallmark of embryonic development that involves a morphological elongation known as axial extension. Furthermore, by employing a combinatorial screening assay, we dissect essential pathways for optimally directing the patterning of pluripotent stem cells into neuromesodermal organoids. This protocol highlights the influence of timing, duration, and concentration of WNT and fibroblast growth factor (FGF) signaling pathways on enhancing early neuromesodermal identity, and later, downstream cell fate specification through combined synergies of retinoid signaling and sonic hedgehog activation. Finally, through robust inhibition of the Notch signaling pathway, this protocol accelerates the acquisition of terminal cell identities. This enhanced organoid model can serve as a powerful tool for studying normal developmental processes as well as investigating complex neurodevelopmental disorders, such as neural tube defects. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Robust generation of 3D hPSC-derived spheroid populations in dynamic motion settings Support Protocol 1: Pluronic F-127 reagent preparation and coating to generate low-attachment suspension culture dishes Basic Protocol 2: Enhanced specification of hPSCs into NMP organoids Support Protocol 2: Combinatorial pathway assay for NMP organoid protocol optimization Basic Protocol 3: Differentiation of NMP organoids along diverse cellular trajectories and accelerated terminal fate specification into neurons, neural crest, and sclerotome derivatives.


Organoids , Pluripotent Stem Cells , Humans , Pregnancy , Female , Hedgehog Proteins , Poloxamer , Fibroblast Growth Factors , Retinoids
8.
Viruses ; 14(8)2022 07 29.
Article En | MEDLINE | ID: mdl-36016298

The CRF02_AG and sub-subtype A6 are currently the predominant HIV-1 variants in the Republic of Uzbekistan, but little is known about their time-spatial clustering patterns in high-risk populations. We have applied molecular evolution methods and network analyses to better understand the transmission patterns of these subtypes by analyzing 316 pol sequences obtained during the surveillance study of HIV drug resistance. Network analysis showed that about one third of the HIV infected persons were organized into clusters, including large clusters with more than 35 members. These clusters were composed mostly of injecting drug users and/or heterosexuals, with women having mainly high centrality within networks identified in both subtypes. Phylogenetic analyses of the 'Uzbek' sequences, including those publicly available, show that Russia and Ukraine played a role as the main sources of the current subtype A6 epidemic in the Republic. At the same time, Uzbekistan has been a local center of the CRF02_AG epidemic spread in the former USSR since the early 2000s. Both of these HIV-1 variants continue to spread in Uzbekistan, highlighting the importance of identifying transmission networks and transmission clusters to prevent further HIV spread, and the need for HIV prevention and education campaigns in high-risk groups.


HIV Infections , HIV Seropositivity , HIV-1 , Female , HIV Infections/epidemiology , HIV-1/genetics , Humans , Molecular Epidemiology , Phylogeny , Uzbekistan/epidemiology
10.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1295-8, 2006.
Article En | MEDLINE | ID: mdl-17946887

This paper discusses the creation of a system for computer-aided communication through automated analysis and processing of electrooculogram signals. In situations of disease or trauma, there may be an inability to communicate with others through standard means such as speech or typing. Eye movement tends to be one of the last remaining active muscle capabilities for people with neurodegenerative disorders, such as amyotrophic lateral sclerosis (ALS) also known as Lou Gehrig's disease. Thus, there is a need for eye movement based systems to enable communication. To meet this need, the Telepathix system was designed to accept eye movement commands denoted by looking to the left, looking to the right, and looking straight ahead to navigate a virtual keyboard. Using a ternary virtual keyboard layout and a multiple feature classification model, a typing speed of 6 letters per minute was achieved.


Artificial Intelligence , Electrooculography/methods , Eye Movements/physiology , Man-Machine Systems , Pattern Recognition, Automated/methods , Task Performance and Analysis , User-Computer Interface , Humans
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