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1.
bioRxiv ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38496681

RESUMO

Lipid membranes are key to the nanoscale compartmentalization of biological systems, but fluorescent visualization of them in intact tissues, with nanoscale precision, is challenging to do with high labeling density. Here, we report ultrastructural membrane expansion microscopy (umExM), which combines a novel membrane label and optimized expansion microscopy protocol, to support dense labeling of membranes in tissues for nanoscale visualization. We validated the high signal-to-background ratio, and uniformity and continuity, of umExM membrane labeling in brain slices, which supported the imaging of membranes and proteins at a resolution of ~60 nm on a confocal microscope. We demonstrated the utility of umExM for the segmentation and tracing of neuronal processes, such as axons, in mouse brain tissue. Combining umExM with optical fluctuation imaging, or iterating the expansion process, yielded ~35 nm resolution imaging, pointing towards the potential for electron microscopy resolution visualization of brain membranes on ordinary light microscopes.

2.
Lancet HIV ; 11(1): e31-e41, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38081198

RESUMO

BACKGROUND: The risk of anal cancer is increased among people with HIV, particularly men who have sex with men. Estimating survival by HIV status and sex and identifying groups at high risk is crucial for documenting prognostic differences between populations. We aimed to compare all-cause and anal cancer-specific survival in patients with anal cancer with and without HIV, stratified by sex, and to identify predictors of survival, stratified by HIV status. METHODS: In this retrospective cohort study, we used data from the HIV/AIDS Cancer Match Study of 13 population-based HIV and cancer registries throughout the USA. We included individuals aged 20-79 years diagnosed with invasive anal cancer between 2001 and 2019. To estimate associations between HIV status and both all-cause and anal cancer-specific mortality overall, we used Cox proportional hazards models, adjusting for year of and age at diagnosis, sex, race and ethnicity, histology, cancer stage, region, and treatment. We also calculated sex-specific adjusted hazard ratios (HRs). By HIV status, we identified characteristics associated with mortality. Models among people with HIV were further adjusted for AIDS status and HIV transmission risk group. FINDINGS: Between Jan 1, 2001, and Dec 31, 2019, 1161 (43·6%) of 2662 patients with anal cancer and HIV and 7722 (35·4%) of 21 824 patients without HIV died. HIV was associated with a 1·35 times (95% CI 1·24-1·47) increase in all-cause mortality among male patients and a 2·47 times (2·10-2·90) increase among female patients. Among patients with HIV, all-cause mortality was increased among non-Hispanic Black individuals (adjusted HR 1·19, 95% CI 1·04-1·38), people with AIDS (1·36, 1·10-1·68), people who inject drugs (PWID; 1·49, 1·17-1·90), patients with adenocarcinoma (2·74, 1·82-4·13), and those with no or unknown surgery treatment (1·34, 1·18-1·53). HIV was associated with anal cancer-specific mortality among female patients only (1·52, 1·18-1·97). Among patients with HIV, anal cancer-specific mortality was increased among patients with adenocarcinoma (3·29, 1·89-5·72), those with no or unknown treatment (1·59, 1·17-2·17), and PWID (1·60, 1·05-2·44). INTERPRETATION: HIV was associated with all-cause mortality among patients with anal cancer, especially women. Anal cancer-specific mortality was elevated among female patients with HIV. As screening for anal cancer becomes more widespread, examining the effects of screening on survival by HIV status and sex is crucial. FUNDING: US National Cancer Institute Intramural Research Program.


Assuntos
Síndrome de Imunodeficiência Adquirida , Adenocarcinoma , Neoplasias do Ânus , Infecções por HIV , Minorias Sexuais e de Gênero , Abuso de Substâncias por Via Intravenosa , Humanos , Masculino , Feminino , Estados Unidos/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina , Estudos Retrospectivos , Síndrome de Imunodeficiência Adquirida/complicações , Abuso de Substâncias por Via Intravenosa/complicações , Neoplasias do Ânus/epidemiologia , Adenocarcinoma/complicações
3.
J Virol ; 97(12): e0133023, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37966249

RESUMO

IMPORTANCE: The essential steps of successful gene delivery by recombinant adeno-associated viruses (rAAVs) include vector internalization, intracellular trafficking, nuclear import, uncoating, double-stranded (ds)DNA conversion, and transgene expression. rAAV2.5T has a chimeric capsid of AAV2 VP1u and AAV5 VP2 and VP3 with the mutation A581T. Our investigation revealed that KIAA0319L, the multiple AAV serotype receptor, is not essential for vector internalization but remains critical for efficient vector transduction to human airway epithelia. Additionally, we identified that a novel gene WDR63, whose cellular function is not well understood, plays an important role in vector transduction of human airway epithelia but not vector internalization and nuclear entry. Our study also discovered the substantial transduction potential of rAAV2.5T in basal stem cells of human airway epithelia, underscoring its utility in gene editing of human airways. Thus, the knowledge derived from this study holds promise for the advancement of gene therapy in the treatment of pulmonary genetic diseases.


Assuntos
Brônquios , Dependovirus , Epitélio , Técnicas de Transferência de Genes , Vetores Genéticos , Transdução Genética , Humanos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , DNA , Epitélio/metabolismo , Epitélio/virologia , Técnicas de Transferência de Genes/tendências , Terapia Genética/métodos , Vetores Genéticos/genética , Brônquios/metabolismo , Brônquios/virologia , Transporte Ativo do Núcleo Celular , Edição de Genes/tendências
4.
bioRxiv ; 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37808760

RESUMO

Recombinant (r)AAV2.5T was selected from the directed evolution of an AAV capsid library in human airway epithelium (HAE). The capsid gene of rAAV2.5T is a chimera of the N-terminal unique coding sequence of AAV2 VP1 unique (VP1u) and the VP2- and VP3-coding sequence of AAV5 with a single amino acid mutation of A581T. We conducted two rounds of genome wide CRISPR gRNA library screening for host factors limiting rAAV2.5T transduction in HeLa S3 cells. The screen identified several genes that are critical for rAAV2.5T transduction in HeLa S3 cells, including previously reported genes KIAA0319L , TM9SF2 , VPS51 , and VPS54 , as well as a novel gene WDR63 . We verified the role of KIAA0319L and WDR63 in rAAV2.5T transduction of polarized HAE by utilizing CRISPR gene knockouts. Although KIAA0319L, a proteinaceous receptor for multiple AAV serotypes, played an essential role in rAAV2.5T transduction of polarized HAE either from apical or basolateral side, our findings demonstrated that the internalization of rAAV2.5T was independent of KIAA0319L. Importantly, we confirmed WDR63 is an important player in rAAV2.5T transduction of HAE, while not being involved in vector internalization and nuclear entry. Furthermore, we identified that the basal stem cells of HAE can be significantly transduced by rAAV2.5T. Significance: The essential steps of a successful gene delivery by rAAV include vector internalization, intracellular trafficking, nuclear import, uncoating, double-stranded (ds)DNA conversion, and transgene expression. rAAV2.5T has a chimeric capsid of AAV2 VP1u and AAV5 VP2 and VP3 with the mutation A581T. Our investigation revealed that KIAA0319L, the multiple AAV serotype receptor, is not essential for vector internalization but remains critical for efficient vector transduction to human airway epithelia. Additionally, we identified that a novel gene WDR63 , whose cellular function is not well understood, plays an important role in vector transduction of human airway epithelia but not vector internalization and nuclear entry. Our study also discovered the substantial transduction potential of rAAV2.5T in basal stem cells of human airway epithelia, underscoring its utility in gene editing of human airways. Thus, the knowledge derived from this study holds promise for the advancement of gene therapy in the treatment of pulmonary genetic diseases.

7.
BioData Min ; 16(1): 14, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038201

RESUMO

BACKGROUND: Quantitative Trait Locus (QTL) analysis and Genome-Wide Association Studies (GWAS) have the power to identify variants that capture significant levels of phenotypic variance in complex traits. However, effort and time are required to select the best methods and optimize parameters and pre-processing steps. Although machine learning approaches have been shown to greatly assist in optimization and data processing, applying them to QTL analysis and GWAS is challenging due to the complexity of large, heterogenous datasets. Here, we describe proof-of-concept for an automated machine learning approach, AutoQTL, with the ability to automate many complicated decisions related to analysis of complex traits and generate solutions to describe relationships that exist in genetic data. RESULTS: Using a publicly available dataset of 18 putative QTL from a large-scale GWAS of body mass index in the laboratory rat, Rattus norvegicus, AutoQTL captures the phenotypic variance explained under a standard additive model. AutoQTL also detects evidence of non-additive effects including deviations from additivity and 2-way epistatic interactions in simulated data via multiple optimal solutions. Additionally, feature importance metrics provide different insights into the inheritance models and predictive power of multiple GWAS-derived putative QTL. CONCLUSIONS: This proof-of-concept illustrates that automated machine learning techniques can complement standard approaches and have the potential to detect both additive and non-additive effects via various optimal solutions and feature importance metrics. In the future, we aim to expand AutoQTL to accommodate omics-level datasets with intelligent feature selection and feature engineering strategies.

8.
Sci Adv ; 9(2): eade0869, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36630517

RESUMO

Parvovirus B19 (B19V) infects human erythroid progenitor cells (EPCs) and causes several hematological disorders and fetal hydrops. Amino acid (aa) 5-68 of minor capsid protein VP1 (VP1u5-68aa) is the minimal receptor binding domain for B19V to enter EPCs. Here, we carried out a genome-wide CRISPR-Cas9 guide RNA screen and identified tyrosine protein kinase receptor UFO (AXL) as a proteinaceous receptor for B19V infection of EPCs. AXL gene silencing in ex vivo expanded EPCs remarkably decreased B19V internalization and replication. Additions of the recombinant AXL extracellular domain or a polyclonal antibody against it upon infection efficiently inhibited B19V infection of ex vivo expanded EPCs. Moreover, B19V VP1u interacted with the recombinant AXL extracellular domain in vitro at a relatively high affinity (KD = 103 nM). Collectively, we provide evidence that AXL is a co-receptor for B19V infection of EPCs.


Assuntos
Receptor Tirosina Quinase Axl , Eritema Infeccioso , Parvovirus B19 Humano , Humanos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Eritema Infeccioso/metabolismo , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/metabolismo , Ligação Proteica , Receptor Tirosina Quinase Axl/metabolismo
9.
bioRxiv ; 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36711526

RESUMO

Background: Quantitative Trait Locus (QTL) analysis and Genome-Wide Association Studies (GWAS) have the power to identify variants that capture significant levels of phenotypic variance in complex traits. However, effort and time are required to select the best methods and optimize parameters and pre-processing steps. Although machine learning approaches have been shown to greatly assist in optimization and data processing, applying them to QTL analysis and GWAS is challenging due to the complexity of large, heterogenous datasets. Here, we describe proof-of-concept for an automated machine learning approach, AutoQTL, with the ability to automate many complex decisions related to analysis of complex traits and generate diverse solutions to describe relationships that exist in genetic data. Results: Using a dataset of 18 putative QTL from a large-scale GWAS of body mass index in the laboratory rat, Rattus norvegicus , AutoQTL captures the phenotypic variance explained under a standard additive model while also providing evidence of non-additive effects including deviations from additivity and 2-way epistatic interactions from simulated data via multiple optimal solutions. Additionally, feature importance metrics provide different insights into the inheritance models and predictive power of multiple GWAS-derived putative QTL. Conclusions: This proof-of-concept illustrates that automated machine learning techniques can be applied to genetic data and has the potential to detect both additive and non-additive effects via various optimal solutions and feature importance metrics. In the future, we aim to expand AutoQTL to accommodate omics-level datasets with intelligent feature selection strategies.

10.
iScience ; 25(12): 105689, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36582482

RESUMO

Advancements in energy storage technologies such as Li-based batteries depend on a deep understanding of the chemical and structural aspects of critical interfaces. Among these, the solid electrolyte interphase (SEI) governs how batteries operate yet remains one of the most elusive to characterize due to its rapid degradation under an electron beam and sensitivity to ambient conditions. In recent years, cryogenic electron microscopy (cryo-EM) has emerged as a promising technique to provide atomic-resolution imaging of beam-sensitive battery materials. Distinct SEIs have been discovered with unique chemical compositions and structural features. In this perspective, the role of cryo-EM in uncovering the physicochemical properties of three classes of SEIs (i.e., compact, extended, and indirect SEI) will be defined and discussed. Furthermore, an in-depth analysis of new cryo-EM imaging modalities will be provided to highlight directions for the future development of cryo-EM.

11.
Nat Mater ; 21(12): 1396-1402, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36396958

RESUMO

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

12.
Malar J ; 21(1): 298, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273147

RESUMO

BACKGROUND: Urban malaria has received insufficient attention in the literature. The prevalence and clinical characteristics of Plasmodium falciparum infection amongst patients presenting with suspected malaria were investigated at a major urban hospital in Douala, Cameroon with a particular focus on anaemia. METHODS: A cross-sectional, 18-week demographic and clinical survey was conducted of patients presenting to the Emergency Department of Douala Military Hospital with suspected malaria, largely defined by the presence or recent history of fever. Venous samples were tested for P. falciparum using rapid diagnostic tests and PCR, and anaemia was defined by haemoglobin level according to WHO definitions. Likelihood ratios (LR), odds ratios (OR), and population attributable risk percent (PARP) were calculated. RESULTS: Participants were ages 8 months to 86 years, 51% were women (257/503), and all districts of Douala were represented. Overall, 38.0% (n = 189/497) were anaemic, including 5.2% (n = 26/497) with severe anaemia. Anaemia prevalence was significantly higher (OR: 2.20, 95% CI 1.41-3.45) among children < 15 years (53.1%, n = 52/98) compared to adults (34%, n = 133/392). Plasmodium falciparum was detected in 37.2% by nested PCR. Among all participants, several factors were associated with clinically significant LR for P. falciparum infection, including age 10-14 years (positive LR: 3.73), living in the island district of Douala VI (positive LR: 3.41), travel to any of three northern regions (positive LR: 5.11), and high fever > 40 °C at presentation (positive LR: 4.83). Among all participants, 8.7% of anaemia was associated with P. falciparum infection, while the PARP was 33.2% among those < 15 years of age and 81.0% among 10-14-year-olds. CONCLUSIONS: The prevalence of P. falciparum infection in the urban hospital was high. Mirroring trends in many rural African settings, older children had the highest positivity rate for P. falciparum infection. Anaemia was also common in all age groups, and for those 10-14 years of age, 80% of the risk for anaemia was associated with P. falciparum infection. Malaria rates in major urban population centres can be high, and more research into the multifactorial causes of anaemia across the age spectrum are needed.


Assuntos
Anemia , Malária Falciparum , Malária , Criança , Adulto , Estados Unidos , Humanos , Feminino , Adolescente , Idoso de 80 Anos ou mais , Masculino , Plasmodium falciparum , Estudos Transversais , Hospitais Militares , Camarões/epidemiologia , Inibidores de Poli(ADP-Ribose) Polimerases , Malária Falciparum/diagnóstico , Anemia/etiologia , Malária/complicações , Prevalência , Hemoglobinas/análise , Hospitais Urbanos
13.
Chem Rev ; 122(18): 14954-14986, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112746

RESUMO

Due to their solution processability and unique photoelectric characteristics, perovskite solar cells (PSCs) have shown considerable promise in the area of renewable energy. Although their power conversion efficiency (PCE) has risen from 3.8% to 25.7% in only a few years, their short lifetime and high material prices continue to be key roadblocks to commercial viability. Charge transporting materials (CTMs), such as hole/electron transporting materials, are critical components in PSCs because they not only govern hole or electron extraction and transporting from the perovskite layer to the electrodes but also protect the perovskite from direct contact with the ambient environment. CTMs are split into two types: inorganic CTMs (ICTMs) and organic CTMs (OCTMs). Because of their inexpensive prices, well-adjusted energy levels, and low temperature solution-processed features, OCTMs have been more frequently explored and employed than ICTMs. Various forms of OCTMs with more straightforward synthetic pathways and better performance have been thoroughly researched. Recent achievements in the development of OCTMs will be discussed and evaluated on a molecular level in this study, which will include a systematic categorization of OCTMs based on molecular functionalization techniques. In order to achieve highly efficient and stable PSCs, we will present insights on the structure-property relationship in the design of OCTMs as well as device stability. We hope that this analysis will serve as a comprehensive reference to molecular design guidelines for various types of OCTMs, spurring greater research toward designing highly efficient and OCTMs for stable PSCs.


Assuntos
Energia Solar , Compostos de Cálcio , Cicloexanos , Mesilatos , Óxidos , Titânio
14.
J Natl Cancer Inst ; 114(9): 1246-1252, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35575389

RESUMO

BACKGROUND: Incidence of anal squamous cell carcinoma (SCC) has increased in the United States. People living with HIV (PLWH) have an elevated risk of anal SCC, and changes in the number of anal SCCs among PLWH may have influenced general population trends. METHODS: Data were obtained from a linkage of HIV and cancer registries in 12 US regions. The proportion of anal SCCs occurring among PLWH was estimated by sex, age group, and race and ethnicity. To assess the impact of anal SCCs among PLWH on general population trends, annual percent changes (APCs) in incidence rates including and excluding anal SCCs among PLWH were estimated. RESULTS: Between 2001 and 2015, 14.5% of 16 110 anal SCC diagnoses occurred in PLWH. In 2013-2015, 35% of anal SCCs among men occurred in PLWH, but only 2% among women. The proportion of anal SCCs among PLWH was highest among 20- to 49-year-olds and Black and Hispanic individuals. General population anal SCC trends among men were strongly influenced by anal SCCs among PLWH: rates increased 4.6%/y (95% confidence interval [CI] = 1.4% to 8.0%) from 2001 to 2009 followed by a statistically non-significant decline (APC = -2.7%/y, 95% CI = -7.1% to 2.0%) from 2009 to 2015, but without anal SCCs among PLWH, rates were stable (APC = 0.7%/y, 95% CI = -0.8% to 2.3%). Anal SCC rates among women increased 3.8%/y (95% CI = 3.2% to 4.4%) during 2001-2012 and then declined statistically non-significantly (APC = -3.8%/y, 95% CI = -6.9% to -0.6%), and anal SCCs among PLWH had little impact on these trends. CONCLUSIONS: During 2001-2015, anal SCCs among PLWH contributed strongly to changes in incidence trends in the general US population among men, but not women.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Infecções por HIV , Neoplasias do Ânus/epidemiologia , Carcinoma de Células Escamosas/patologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , Sistema de Registros , Estados Unidos/epidemiologia
15.
Curr Opin Anaesthesiol ; 35(2): 195-200, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142728

RESUMO

PURPOSE OF REVIEW: COVID-19 pandemic has created profound ethical challenges, not only for clinical decision-making but also for defining physician professional conduct. RECENT FINDINGS: Multiple ethical questions arose as the COVID-19 pandemic ravaged globally, including physician obligations in a pandemic, allotment of personal protective equipment, care of unvaccinated patients, discern between evidence-based and unreliable information, addressing end-of-life wishes, implications of involving medical students in a public health crisis, and finally physician burnout aggravated by a pandemic. SUMMARY: There is a need to redefine existing medical professionalism standards so that future healthcare professionals are well prepared to deal with similar public health crisis.


Assuntos
Esgotamento Profissional , COVID-19 , Esgotamento Profissional/etiologia , Esgotamento Profissional/prevenção & controle , Humanos , Pandemias/prevenção & controle , Profissionalismo , SARS-CoV-2
16.
Adv Mater ; 34(10): e2107330, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34710251

RESUMO

Near-infrared (NIR)-absorbing organic semiconductors have opened up many exciting opportunities for organic photovoltaic (OPV) research. For example, new chemistries and synthetical methodologies have been developed; especially, the breakthrough Y-series acceptors, originally invented by our group, specifically Y1, Y3, and Y6, have contributed immensely to boosting single-junction solar cell efficiency to around 19%; novel device architectures such as tandem and transparent organic photovoltaics have been realized. The concept of NIR donors/acceptors thus becomes a turning point in the OPV field. Here, the development of NIR-absorbing materials for OPVs is reviewed. According to the low-energy absorption window, here, NIR photovoltaic materials (p-type (polymers) and n-type (fullerene and nonfullerene)) are classified into four categories: 700-800 nm, 800-900 nm, 900-1000 nm, and greater than 1000 nm. Each subsection covers the design, synthesis, and utilization of various types of donor (D) and acceptor (A) units. The structure-property relationship between various kinds of D, A units and absorption window are constructed to satisfy requirements for different applications. Subsequently, a variety of applications realized by NIR materials, including transparent OPVs, tandem OPVs, photodetectors, are presented. Finally, challenges and future development of novel NIR materials for the next-generation organic photovoltaics and beyond are discussed.

17.
mBio ; 12(3)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975939

RESUMO

The spike (S) polypeptide of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) consists of the S1 and S2 subunits and is processed by cellular proteases at the S1/S2 boundary that contains a furin cleavage site (FCS), 682RRAR↓S686 Various deletions surrounding the FCS have been identified in patients. When SARS-CoV-2 propagated in Vero cells, it acquired deletions surrounding the FCS. We studied the viral transcriptome in Vero cell-derived SARS-CoV-2-infected primary human airway epithelia (HAE) cultured at an air-liquid interface (ALI) with an emphasis on the viral genome stability of the FCS. While we found overall the viral transcriptome is similar to that generated from infected Vero cells, we identified a high percentage of mutated viral genome and transcripts in HAE-ALI. Two highly frequent deletions were found at the FCS region: a 12 amino acid deletion (678TNSPRRAR↓SVAS689) that contains the underlined FCS and a 5 amino acid deletion (675QTQTN679) that is two amino acids upstream of the FCS. Further studies on the dynamics of the FCS deletions in apically released virions from 11 infected HAE-ALI cultures of both healthy and lung disease donors revealed that the selective pressure for the FCS maintains the FCS stably in 9 HAE-ALI cultures but with 2 exceptions, in which the FCS deletions are retained at a high rate of >40% after infection of ≥13 days. Our study presents evidence for the role of unique properties of human airway epithelia in the dynamics of the FCS region during infection of human airways, which is likely donor dependent.IMPORTANCE Polarized human airway epithelia at an air-liquid interface (HAE-ALI) are an in vitro model that supports efficient infection of SARS-CoV-2. The spike (S) protein of SARS-CoV-2 contains a furin cleavage site (FCS) at the boundary of the S1 and S2 domains which distinguishes it from SARS-CoV. However, FCS deletion mutants have been identified in patients and in vitro cell cultures, and how the airway epithelial cells maintain the unique FCS remains unknown. We found that HAE-ALI cultures were capable of suppressing two prevalent FCS deletion mutants (Δ678TNSPRRAR↓SVAS689 and Δ675QTQTN679) that were selected during propagation in Vero cells. While such suppression was observed in 9 out of 11 of the tested HAE-ALI cultures derived from independent donors, 2 exceptions that retained a high rate of FCS deletions were also found. Our results present evidence of the donor-dependent properties of human airway epithelia in the evolution of the FCS during infection.


Assuntos
Brônquios/virologia , Furina/metabolismo , Mucosa Respiratória/virologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Transcriptoma , Animais , Brônquios/citologia , Células Cultivadas , Chlorocebus aethiops , Células Epiteliais/virologia , Humanos , RNA-Seq , Mucosa Respiratória/citologia , Deleção de Sequência , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero
18.
Front Cell Infect Microbiol ; 11: 621738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33680990

RESUMO

The severity of toxoplasmosis depends on a combination of host and parasite factors. Among them, the Toxoplasma strain causing the infection is an important determinant of the disease outcome. Type 2 strains dominate in Europe, whereas in North America type 2, followed by type 3 and 12 strains are commonly isolated from wildlife and patients. To identify the strain type a person is infected with, serological typing provides a promising alternative to the often risky and not always possible biopsy-based DNA methods of genotyping. However, despite recent advances in serotyping, improvements in the sensitivity and specificity are still needed, and it does not yet discriminate among the major Toxoplasma lineages infecting people. Moreover, since infections caused by non-1/2/3 strains have been associated with more severe disease, the ability to identify these is critical. In the present study we investigated the diagnostic potential of an ELISA-based assay using 28 immunogenic Toxoplasma peptides derived from a recent large-scale peptide array screen. Our results show that a discrete number of peptides, derived from Toxoplasma dense granule proteins (GRA3, GRA5, GRA6, and GRA7) was sufficient to discriminate among archetypal strains that infect mice and humans. The assay specifically relies on ratios that compare individual serum reactivities against GRA-specific polymorphic peptide variants in order to determine a "reactivity fingerprint" for each of the major strains. Importantly, nonarchetypal strains that possess a unique combination of alleles, different from types 1/2/3, showed either a non-reactive, or different combinatorial, mixed serum reactivity signature that was diagnostic in its own right, and that can be used to identify these strains. Of note, we identified a distinct "HG11/12" reactivity pattern using the GRA6 peptides that is able to distinguish HG11/12 from archetypal North American/European strain infections.


Assuntos
Toxoplasma , Toxoplasmose , Animais , Antígenos de Protozoários/genética , Europa (Continente) , Humanos , Camundongos , América do Norte , Peptídeos , Proteínas de Protozoários/genética , Toxoplasma/genética , Toxoplasmose/diagnóstico
19.
Adv Mater ; 33(12): e2006120, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33586281

RESUMO

The synthesis of a new molecule, SFIC-Cl, is reported, which features enhanced π-electron delocalization by spiroconjugation and narrowed bandgap by chlorination. SFIC-Cl is integrated into a single-crystal transistor (OFET) and organic light-emitting diode (OLED). The material demonstrates remarkable transport abilities across various solution-processed OFETs and retains efficient radiance in a near-infrared OLED emitting light at 700 nm. Furthermore, the intermolecular multi-dimensional connection of SFIC-Cl enables the fabrication of a single-component large-area (2 × 2 cm2 ) near-infrared OLED by spin-coating. The SFIC-Cl-acceptor-based solar cell shows excellent power conversion efficiency of 10.16% resulting from the broadened and strong absorption and well-matched energy levels. The study demonstrates that chlorinated spiroconjugated fused systems offer a novel direction toward the development of high-performance organic semiconductor materials for hybrid organic electronic devices.

20.
Lab Chip ; 21(5): 904-915, 2021 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-33438699

RESUMO

Asymmetric surface acoustic waves have been shown useful in separating particles and cells in many microfluidics designs, mostly notably sessile microdroplets. However, no one has successfully extracted target particles or cells for later use from such samples. We present a novel omnidirectional spiral surface acoustic wave (OSSAW) design that exploits a new cut of lithium niobate, 152 Y-rotated, to rapidly rotate a microliter sessile drop to ∼10 g, producing efficient multi-size particle separation. We further extract the separated particles for the first time, demonstrating the ability to target specific particles, for example, platelets from mouse blood for further integrated point-of-care diagnostics. Within ∼5 s of surface acoustic wave actuation, particles with diameter of 5 µm and 1 µm can be separated into two portions with a purity of 83% and 97%, respectively. Red blood cells and platelets within mouse blood are further demonstrated to be separated with a purity of 93% and 84%, respectively. These advancements potentially provide an effective platform for whole blood separation and point-of-care diagnostics without need for micro or nanoscale fluidic enclosures.


Assuntos
Microfluídica , Som , Animais , Separação Celular , Camundongos
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