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1.
PLoS Genet ; 20(2): e1011138, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38315730

RESUMO

The presence of large protein inclusions is a hallmark of neurodegeneration, and yet the precise molecular factors that contribute to their formation remain poorly understood. Screens using aggregation-prone proteins have commonly relied on downstream toxicity as a readout rather than the direct formation of aggregates. Here, we combined a genome-wide CRISPR knockout screen with Pulse Shape Analysis, a FACS-based method for inclusion detection, to identify direct modifiers of TDP-43 aggregation in human cells. Our screen revealed both canonical and novel proteostasis genes, and unearthed SRRD, a poorly characterized protein, as a top regulator of protein inclusion formation. APEX biotin labeling reveals that SRRD resides in proximity to proteins that are involved in the formation and breakage of disulfide bonds and to intermediate filaments, suggesting a role in regulation of the spatial dynamics of the intermediate filament network. Indeed, loss of SRRD results in aberrant intermediate filament fibrils and the impaired formation of aggresomes, including blunted vimentin cage structure, during proteotoxic stress. Interestingly, SRRD also localizes to aggresomes and unfolded proteins, and rescues proteotoxicity in yeast whereby its N-terminal low complexity domain is sufficient to induce this affect. Altogether this suggests an unanticipated and broad role for SRRD in cytoskeletal organization and cellular proteostasis.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Filamentos Intermediários , Humanos , Filamentos Intermediários/genética , Filamentos Intermediários/metabolismo , Citoesqueleto/genética , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo
2.
Mod Pathol ; : 100556, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964502

RESUMO

Recently, low HER2 protein expression has been proposed as a predictive biomarker for response to antibody-drug conjugate trastuzumab deruxtecan (T-DXd) in metastatic breast cancer. HER2 expression in non-small cell lung cancer (NSCLC) patients has never been carefully measured, and little is known about the frequency of cases with unamplified but detectable levels of the protein. Although some HER2-targeted therapies have been studied in NSCLC patients, they have been restricted to those with genomic ERBB2 gene alterations, which only represent relatively rare cases of NSCLC. Still, emerging investigations of T-DXd in NSCLC have shown promise in patients with unamplified HER2. Taken together, we hypothesize that there may be many cases of NSCLC with levels of HER2 protein expression comparable to levels seen in breast cancer who benefit from T-DXd. Here, we used a previously validated, analytic, quantitative immunofluorescence (QIF) assay that is more sensitive than legacy clinical HER2 immunohistochemistry assays. We measured HER2 protein levels in NSCLC cases to determine the proportion of cases with detectable HER2 expression. Using cell line calibration microarrays alongside our QIF method enabled us to convert HER2 signal into units of attomoles per mm2. We found that over 63% of the 741 analyzed NSCLC cases exhibited HER2 expression above the limit of detection, with more than 17% of them exceeding the lower limit of quantification. While the threshold for response to T-DXd in breast cancer is still unknown, many cases of NSCLC have expression in a range comparable to breast cancer cases with immunohistochemistry scores of 1+ or 2+. Our assay could potentially select NSCLC cases with detectable target (i.e., HER2) that might benefit from HER2 antibody-drug conjugates, irrespective of ERBB2 genomic alterations.

3.
Am J Respir Crit Care Med ; 207(12): 1565-1575, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37212596

RESUMO

Rationale: Indirect airway hyperresponsiveness (AHR) is a highly specific feature of asthma, but the underlying mechanisms responsible for driving indirect AHR remain incompletely understood. Objectives: To identify differences in gene expression in epithelial brushings obtained from individuals with asthma who were characterized for indirect AHR in the form of exercise-induced bronchoconstriction (EIB). Methods: RNA-sequencing analysis was performed on epithelial brushings obtained from individuals with asthma with EIB (n = 11) and without EIB (n = 9). Differentially expressed genes (DEGs) between the groups were correlated with measures of airway physiology, sputum inflammatory markers, and airway wall immunopathology. On the basis of these relationships, we examined the effects of primary airway epithelial cells (AECs) and specific epithelial cell-derived cytokines on both mast cells (MCs) and eosinophils (EOS). Measurements and Main Results: We identified 120 DEGs in individuals with and without EIB. Network analyses suggested critical roles for IL-33-, IL-18-, and IFN-γ-related signaling among these DEGs. IL1RL1 expression was positively correlated with the density of MCs in the epithelial compartment, and IL1RL1, IL18R1, and IFNG were positively correlated with the density of intraepithelial EOS. Subsequent ex vivo modeling demonstrated that AECs promote sustained type 2 (T2) inflammation in MCs and enhance IL-33-induced T2 gene expression. Furthermore, EOS increase the expression of IFNG and IL13 in response to both IL-18 and IL-33 as well as exposure to AECs. Conclusions: Circuits involving epithelial interactions with MCs and EOS are closely associated with indirect AHR. Ex vivo modeling indicates that epithelial-dependent regulation of these innate cells may be critical in indirect AHR and modulating T2 and non-T2 inflammation in asthma.


Assuntos
Asma , Hipersensibilidade Respiratória , Humanos , Interleucina-18 , Interleucina-33/genética , Células Epiteliais/patologia , Inflamação , Imunidade Inata
4.
J Allergy Clin Immunol ; 151(6): 1484-1493, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36708815

RESUMO

BACKGROUND: Mast cells (MCs) within the airway epithelium in asthma are closely related to airway dysfunction, but cross talk between airway epithelial cells (AECs) and MCs in asthma remains incompletely understood. Human rhinovirus (RV) infections are key triggers for asthma progression, and AECs from individuals with asthma may have dysregulated antiviral responses. OBJECTIVE: We utilized primary AECs in an ex vivo coculture model system to examine cross talk between AECs and MCs after epithelial rhinovirus infection. METHODS: Primary AECs were obtained from 11 children with asthma and 10 healthy children, differentiated at air-liquid interface, and cultured in the presence of laboratory of allergic diseases 2 (LAD2) MCs. AECs were infected with rhinovirus serogroup A 16 (RV16) for 48 hours. RNA isolated from both AECs and MCs underwent RNA sequencing. Direct effects of epithelial-derived interferons on LAD2 MCs were examined by real-time quantitative PCR. RESULTS: MCs increased expression of proinflammatory and antiviral genes in AECs. AECs demonstrated a robust antiviral response after RV16 infection that resulted in significant changes in MC gene expression, including upregulation of genes involved in antiviral responses, leukocyte activation, and type 2 inflammation. Subsequent ex vivo modeling demonstrated that IFN-ß induces MC type 2 gene expression. The effects of AEC donor phenotype were small relative to the effects of viral infection and the presence of MCs. CONCLUSIONS: There is significant cross talk between AECs and MCs, which are present in the epithelium in asthma. Epithelial-derived interferons not only play a role in viral suppression but also further alter MC immune responses including specific type 2 genes.


Assuntos
Asma , Infecções por Enterovirus , Infecções por Picornaviridae , Criança , Humanos , Interferons , Rhinovirus/fisiologia , Mastócitos/metabolismo , Epitélio/metabolismo , Células Epiteliais , Antivirais/farmacologia , Imunidade
5.
J Am Chem Soc ; 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36749951

RESUMO

The principles for the selection of the stereochemistry of phospholipids of biological membranes remain unclear and continue to be debated. Therefore, any new experiments on this topic may help progress in this field. To address this question, three libraries of constitutional isomeric glycerol-amphiphilic Janus dendrimers (JDs) with nonsymmetric homochiral, racemic, and symmetric achiral branching points were synthesized by an orthogonal-modular-convergent methodology. These JDs amplify self-assembly, and therefore, monodisperse vesicles known as dendrimersomes (DSs) with predictable dimensions programmed by JD concentration were assembled by rapid injection of their ethanol solution into water. DSs of homochiral JD enantiomers, racemic, including mixtures of different enantiomers, and achiral exhibited similar DS size-concentration dependence. However, the number of bilayers of DSs assembled from homochiral, achiral, and racemic JDs determined by cryo-TEM were different. Statistical analysis of the number of bilayers and coarse-grained molecular dynamics simulations demonstrated that homochiral JDs formed predominantly unilamellar DSs. Symmetric achiral JDs assembled only unilamellar DSs while racemic JDs favored multilamellar DSs. Since cell membranes are unilamellar, these results indicate a new rationale for nonsymmetric homochiral vs racemic selection. Simultaneously, these experiments imply that the symmetric achiral lipids forming more stable membrane, probably had been the preferable assemblies of prebiotic cell membranes.

6.
J Am Chem Soc ; 145(36): 19422-19439, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37642501

RESUMO

Wastewater is an underleveraged resource; it contains pollutants that can be transformed into valuable high-purity products. Innovations in chemistry and chemical engineering will play critical roles in valorizing wastewater to remediate environmental pollution, provide equitable access to chemical resources and services, and secure critical materials from diminishing feedstock availability. This perspective envisions electrochemical wastewater refining─the use of electrochemical processes to tune and recover specific products from wastewaters─as the necessary framework to accelerate wastewater-based electrochemistry to widespread practice. We define and prescribe a use-informed approach that simultaneously serves specific wastewater-pollutant-product triads and uncovers a mechanistic understanding generalizable to broad use cases. We use this approach to evaluate research needs in specific case studies of electrocatalysis, stoichiometric electrochemical conversions, and electrochemical separations. Finally, we provide rationale and guidance for intentionally expanding the electrochemical wastewater refining product portfolio. Wastewater refining will require a coordinated effort from multiple expertise areas to meet the urgent need of extracting maximal value from complex, variable, diverse, and abundant wastewater resources.

7.
BMC Public Health ; 23(1): 254, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747209

RESUMO

BACKGROUND: Understanding factors that influence healthy or unhealthy eating can inform intervention strategies. This study ascertained whether and how unintentional exposure to food and nutrition information influenced healthy eating concerns. The study tested body comparison, body satisfaction, and body mass index as three mechanisms that potentially link food information encounter, commonly known as information scanning, to healthy eating concerns. METHODS: A sample of 440 online participants (mean age = 29.15 years) was used to investigate: (1) how unintentional exposure to food and nutrition information, i.e., information encounter (IE), affects healthy eating concerns (HEC); (2) how the effect of IE on HEC is mediated by body comparison (BC); (3) how the paths of the mediation model are moderated by body satisfaction (BS) or body mass index (BMI). RESULTS: The findings show a positive and sizable total effect of IE on HEC - a whole-scale increase in information encounter is associated with a substantial increase in healthy eating concerns by 15 percentage points (bp = 0.150). BC is found to mediate the effect of IE on HEC in an all-positive complementary mediation. Both the indirect and the direct-and-remainder paths show sizable effects. The mediated path contributes about 20% of the total effect between IE and HEC (cp = 20%), while the direct-and-remainder path contributes the rest (cp = 80%). BS was found to moderate the relationship between IE and BC, the first leg of the mediation. The moderation effect is large - the effect of IE on BC is much smaller on the highly and the moderately satisfied than on the lowly satisfied (slope differential bp = -.60). BMI was found to moderate the direct-and-remainder effect of IE on HEC, controlling BC. That is, the effect of IE on HEC, after filtering out the mediated effect through BC, is much larger for those with high or low BMI than those with healthy BMI (slope differential bp = .32). CONCLUSIONS: Exposure, even if unintentional, to food and nutrition information is an important predictor of HEC. BC, BS, and BMI are important factors that help to explain the process through which information affects behaviors.


Assuntos
Dieta Saudável , Redução de Peso , Humanos , Adulto , Índice de Massa Corporal , Estado Nutricional , Satisfação Pessoal , Comportamento Alimentar , Ingestão de Alimentos
8.
J Med Internet Res ; 25: e47595, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37902832

RESUMO

BACKGROUND: Generation Z (born 1995-2010) members are digital residents who use technology and the internet more frequently than any previous generation to learn about their health. They are increasingly moving away from conventional methods of seeking health information as technology advances quickly and becomes more widely available, resulting in a more digitalized health care system. Similar to all groups, Generation Z has specific health care requirements and preferences, and their use of technology influences how they look for health information. However, they have often been overlooked in scholarly research. OBJECTIVE: First, we aimed to identify the information-seeking preferences of older individuals and Generation Z (those between the ages of 18 and 26 years); second, we aimed to predict the effects of digital health literacy and health empowerment in both groups. We also aimed to identify factors that impact how both groups engage in digital health and remain in control of their own health. METHODS: The Health Information National Trends Survey was adopted for further use in 2022. We analyzed 1862 valid data points by conducting a survey among Chinese respondents to address the research gap. A descriptive analysis, 2-tailed t test, and multiple linear regression were applied to the results. RESULTS: When compared with previous generations, Generation Z respondents (995/1862, 53.44%) were more likely to use the internet to find out about health-related topics, whereas earlier generations relied more on traditional media and interpersonal contact. Web-based information-seeking behavior is predicted by digital health literacy (Generation Z: ß=.192, P<.001; older population: ß=.337, P<.001). While this was happening, only seeking health information from physicians positively predicted health empowerment (Generation Z: ß=.070, P=.002; older population: ß=.089, P<.001). Despite more frequent use of the internet to learn about their health, Generation Z showed lower levels of health empowerment and less desire to look for health information, overall. CONCLUSIONS: This study examined and compared the health information-seeking behaviors of Generation Z and older individuals to improve their digital health literacy and health empowerment. The 2 groups demonstrated distinct preferences regarding their choice of information sources. Health empowerment and digital health literacy were both significantly related to information-seeking behaviors.


Assuntos
Letramento em Saúde , Telemedicina , Humanos , Adolescente , Adulto Jovem , Adulto , Comportamento de Busca de Informação , Letramento em Saúde/métodos , Estudos Transversais , Telemedicina/métodos , Inquéritos e Questionários , Internet , Poder Psicológico
9.
J Am Chem Soc ; 144(11): 4746-4753, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35263098

RESUMO

Viral and synthetic vectors for delivery of nucleic acids impacted genetic nanomedicine by aiding the rapid development of the extraordinarily efficient Covid-19 vaccines. Access to targeted delivery of nucleic acids is expected to expand the field of nanomedicine beyond most expectations. Both viral and synthetic vectors have advantages and disadvantages. The major advantage of the synthetic vectors is their unlimited synthetic capability. The four-component lipid nanoparticles (LNPs) are the leading nonviral vector for mRNA used by Pfizer and Moderna in Covid-19 vaccines. Their synthetic capacity inspired us to develop a one-component multifunctional sequence-defined ionizable amphiphilic Janus dendrimer (IAJD) delivery system for mRNA. The first experiments on IAJDs provided, through a rational-library design combined with orthogonal-modular accelerated synthesis and sequence control in their hydrophilic part, some of the most active synthetic vectors for the delivery of mRNA to lung. The second experiments employed a similar strategy, generating, by a less complex hydrophilic structure, a library of IAJDs targeting spleen, liver, and lung. Here, we report preliminary studies designing the hydrophobic region of IAJDs by using dissimilar alkyl lengths and demonstrate the unexpectedly important role of the primary structure of the hydrophobic part of IAJDs by increasing up to 90.2-fold the activity of targeted delivery of mRNA to spleen, lymph nodes, liver, and lung. The principles of the design strategy reported here and in previous publications indicate that IAJDs could have a profound impact on the future of genetic nanomedicine.


Assuntos
COVID-19 , Dendrímeros , Nanopartículas , Vacinas contra COVID-19 , Dendrímeros/química , Humanos , Lipossomos , Nanopartículas/química , RNA Mensageiro/química , RNA Mensageiro/genética
10.
J Am Chem Soc ; 144(13): 5739-5744, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35315649

RESUMO

The electrochemical nitrate reduction reaction (NO3RR) on titanium introduces significant surface reconstruction and forms titanium hydride (TiHx, 0 < x ≤ 2). With ex situ grazing-incidence X-ray diffraction (GIXRD) and X-ray absorption spectroscopy (XAS), we demonstrated near-surface TiH2 enrichment with increasing NO3RR applied potential and duration. This quantitative relationship facilitated electrochemical treatment of Ti to form TiH2/Ti electrodes for use in NO3RR, thereby decoupling hydride formation from NO3RR performance. A wide range of NO3RR activity and selectivity on TiH2/Ti electrodes between -0.4 and -1.0 VRHE was observed and analyzed with density functional theory (DFT) calculations on TiH2(111). This work underscores the importance of relating NO3RR performance with near-surface electrode structure to advance catalyst design and operation.


Assuntos
Nitratos , Titânio , Eletrodos , Nitratos/química , Oxirredução , Titânio/química , Raios X
11.
Cerebellum ; 21(4): 606-614, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35857265

RESUMO

This report presents the first comprehensive database that specifically compiles genes critical for cerebellar development and function. The Cerebellar Gene Database details genes that, when perturbed in mouse models, result in a cerebellar phenotype according to available data from both Mouse Genome Informatics and PubMed, as well as references to the corresponding studies for further examination. This database also offers a compilation of human genetic disorders with a cerebellar phenotype and their associated gene information from the Online Mendelian Inheritance in Man (OMIM) database. By comparing and contrasting the mouse and human datasets, we observe that only a small proportion of human mutant genes with a cerebellar phenotype have been studied in mouse knockout models. Given the highly conserved nature between mouse and human genomes, this surprising finding highlights how mouse genetic models can be more frequently employed to elucidate human disease etiology. On the other hand, many mouse genes identified in the present study that are known to lead to a cerebellar phenotype when perturbed have not yet been found to be pathogenic in the cerebellum of humans. This database furthers our understanding of human cerebellar disorders with yet-to-be-identified genetic causes. It is our hope that this gene database will serve as an invaluable tool for gathering background information, generating hypotheses, and facilitating translational research endeavors. Moreover, we encourage continual inputs from the research community in making this compilation a living database, one that remains up-to-date with the advances in cerebellar research.


Assuntos
Cerebelo , Bases de Dados Genéticas , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Fenótipo
12.
Environ Sci Technol ; 56(22): 16134-16143, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36223185

RESUMO

Ion exchange (IX) is a promising technology for selective nitrogen recovery from urine; however, IX requires chemical-intensive regeneration that escalates energy consumption and carbon emissions. To overcome this barrier, we demonstrated and investigated a novel electrified IX stripping process (EXS) enabling electrochemical in situ IX regeneration with simultaneous ammonia stripping. EXS combines a weak acid cation exchange resin (WAC) to concentrate ammonia, a bipolar membrane to produce protons for WAC regeneration, and membrane stripping to recover the eluted ammonium from WAC. We observed over 80% regeneration (elution from resin) and recovery (membrane stripping) efficiencies during multiple adsorption-recovery cycles with synthetic and real urine. Comparing WAC with a strong acid cation exchange resin illustrated the critical role of the proton affinity of resin moieties in regulating resin regenerability and conductivity in EXS, which we distinguished from the rationale for material choice in electrodeionization. Compared to other electrochemical recovery methods using unamended wastewater as an electrolyte, EXS enabled control of electrolyte composition during recovery by separating and equalizing influent ammonium via WAC-mediated removal. This electrolyte engineering facilitated tunable EXS energy efficiency (100-300 MJ/kg N). This study informs the design of electrified, intensified systems that enable decentralized nitrogen recovery from urine.


Assuntos
Compostos de Amônio , Nitrogênio , Troca Iônica , Amônia , Água , Resinas de Troca de Cátion , Águas Residuárias
13.
Environ Sci Technol ; 56(12): 8712-8721, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35656915

RESUMO

Treatment of domestic wastewater can recover valuable resources, including clean water, energy, and ammonia. Important metrics for these systems are greenhouse gas (GHG) emissions and embodied energy, both of which are location- and technology-dependent. Here, we determine the embodied energy and GHG emissions resulting from a conventional process train, and we compare them to a nonconventional process train. The conventional train assumes freshwater conveyance from a pristine source that requires energy for pumping (US average of 0.29 kWh/m3), aerobic secondary treatment with N removal as N2, and Haber-Bosch synthesis of ammonia. Overall, we find that this process train has an embodied energy of 1.02 kWh/m3 and a GHG emission of 0.77 kg-CO2eq/m3. We compare these metrics to those of a nonconventional process train that features anaerobic secondary treatment technology followed by further purification of the effluent by reverse osmosis and air stripping for ammonia recovery. This "short-cut" process train reduces embodied energy to 0.88 kWh/m3 and GHG emissions to 0.42 kg-CO2eq/m3, while offsetting demand for ammonia from the Haber-Bosch process and decreasing reliance upon water transported over long distances. Finally, to assess the potential impacts of nonconventional nitrogen removal technology, we compared the embodied energy and GHG emissions resulting from partial nitritation/anammox coupled to anaerobic secondary treatment. The resulting process train enabled a lower embodied energy but increased GHG emissions, largely due to emissions of N2O, a potent greenhouse gas.


Assuntos
Gases de Efeito Estufa , Águas Residuárias , Amônia , Efeito Estufa , Eliminação de Resíduos Líquidos , Água
14.
Proc Natl Acad Sci U S A ; 116(8): 2837-2842, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30718416

RESUMO

Glycan-lectin recognition is assumed to elicit its broad range of (patho)physiological functions via a combination of specific contact formation with generation of complexes of distinct signal-triggering topology on biomembranes. Faced with the challenge to understand why evolution has led to three particular modes of modular architecture for adhesion/growth-regulatory galectins in vertebrates, here we introduce protein engineering to enable design switches. The impact of changes is measured in assays on cell growth and on bridging fully synthetic nanovesicles (glycodendrimersomes) with a chemically programmable surface. Using the example of homodimeric galectin-1 and monomeric galectin-3, the mutual design conversion caused qualitative differences, i.e., from bridging effector to antagonist/from antagonist to growth inhibitor and vice versa. In addition to attaining proof-of-principle evidence for the hypothesis that chimera-type galectin-3 design makes functional antagonism possible, we underscore the value of versatile surface programming with a derivative of the pan-galectin ligand lactose. Aggregation assays with N,N'-diacetyllactosamine establishing a parasite-like surface signature revealed marked selectivity among the family of galectins and bridging potency of homodimers. These findings provide fundamental insights into design-functionality relationships of galectins. Moreover, our strategy generates the tools to identify biofunctional lattice formation on biomembranes and galectin-reagents with therapeutic potential.


Assuntos
Galectina 1/química , Galectina 3/química , Glicoconjugados/química , Polissacarídeos/química , Amino Açúcares/química , Amino Açúcares/metabolismo , Sítios de Ligação , Proteínas Sanguíneas , Adesão Celular/genética , Proliferação de Células/genética , Galectina 1/genética , Galectina 3/genética , Galectinas , Humanos , Lactose/química , Ligantes , Nanopartículas/química , Polissacarídeos/genética
15.
J Am Chem Soc ; 143(43): 17975-17982, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34672554

RESUMO

Targeted and efficient delivery of nucleic acids with viral and synthetic vectors is the key step of genetic nanomedicine. The four-component lipid nanoparticle synthetic delivery systems consisting of ionizable lipids, phospholipids, cholesterol, and a PEG-conjugated lipid, assembled by microfluidic or T-tube technology, have been extraordinarily successful for delivery of mRNA to provide Covid-19 vaccines. Recently, we reported a one-component multifunctional sequence-defined ionizable amphiphilic Janus dendrimer (IAJD) synthetic delivery system for mRNA relying on amphiphilic Janus dendrimers and glycodendrimers developed in our laboratory. Amphiphilic Janus dendrimers consist of functional hydrophilic dendrons conjugated to hydrophobic dendrons. Co-assembly of IAJDs with mRNA into dendrimersome nanoparticles (DNPs) occurs by simple injection in acetate buffer, rather than by microfluidic devices, and provides a very efficient system for delivery of mRNA to lung. Here we report the replacement of most of the hydrophilic fragment of the dendron from IAJDs, maintaining only its ionizable amine, while changing its interconnecting group to the hydrophobic dendron from amide to ester. The resulting IAJDs demonstrated that protonated ionizable amines play dual roles of hydrophilic fragment and binding ligand for mRNA, changing delivery from lung to spleen and/or liver. Replacing the interconnecting ester with the amide switched the delivery back to lung. Delivery predominantly to liver is favored by pairs of odd and even alkyl groups in the hydrophobic dendron. This simple structural change transformed the targeted delivery of mRNA mediated with IAJDs, from lung to liver and spleen, and expands the utility of DNPs from therapeutics to vaccines.


Assuntos
Dendrímeros/química , RNA Mensageiro/química , Aminas/química , Animais , Ésteres/química , Interações Hidrofóbicas e Hidrofílicas , Íons/química , Camundongos , Nanopartículas/química , RNA Mensageiro/imunologia , RNA Mensageiro/metabolismo , Vacinas Sintéticas/química , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/metabolismo
16.
J Am Chem Soc ; 143(31): 12315-12327, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324336

RESUMO

Efficient viral or nonviral delivery of nucleic acids is the key step of genetic nanomedicine. Both viral and synthetic vectors have been successfully employed for genetic delivery with recent examples being DNA, adenoviral, and mRNA-based Covid-19 vaccines. Viral vectors can be target specific and very efficient but can also mediate severe immune response, cell toxicity, and mutations. Four-component lipid nanoparticles (LNPs) containing ionizable lipids, phospholipids, cholesterol for mechanical properties, and PEG-conjugated lipid for stability represent the current leading nonviral vectors for mRNA. However, the segregation of the neutral ionizable lipid as droplets in the core of the LNP, the "PEG dilemma", and the stability at only very low temperatures limit their efficiency. Here, we report the development of a one-component multifunctional ionizable amphiphilic Janus dendrimer (IAJD) delivery system for mRNA that exhibits high activity at a low concentration of ionizable amines organized in a sequence-defined arrangement. Six libraries containing 54 sequence-defined IAJDs were synthesized by an accelerated modular-orthogonal methodology and coassembled with mRNA into dendrimersome nanoparticles (DNPs) by a simple injection method rather than by the complex microfluidic technology often used for LNPs. Forty four (81%) showed activity in vitro and 31 (57%) in vivo. Some, exhibiting organ specificity, are stable at 5 °C and demonstrated higher transfection efficiency than positive control experiments in vitro and in vivo. Aside from practical applications, this proof of concept will help elucidate the mechanisms of packaging and release of mRNA from DNPs as a function of ionizable amine concentration, their sequence, and constitutional isomerism of IAJDs.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Tensoativos/química , Animais , Dendrímeros/síntese química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Estudo de Prova de Conceito , Tensoativos/síntese química
17.
Hepatology ; 71(6): 1910-1922, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31610027

RESUMO

BACKGROUND AND AIMS: Survival data among patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) after achieving sustained virologic response (SVR) with interferon-free direct-acting antivirals (DAAs) in both Asian and western countries are limited. Survival rates were compared between patients with HCV-related HCC who were untreated for HCV and those who achieved SVR. APPROACH AND RESULTS: Using data from two U.S. and six Asian centers from 2005 to 2017, we categorized 1,676 patients who were mono-infected with HCV-related HCC into patients untreated for HCV (untreated group) and DAA-treated patients with SVR (SVR group) and matched by propensity score matching (PSM); multivariable Cox regression with HCV treatment status as a time-varying covariate was used to determine mortality risk and landmark analysis to avoid immortal time bias. There were 1,239 untreated patients and 437 patients with SVR. After PSM, background risks of the 321 pairs of matched patients were balanced (all P > 0.05). After time-varying adjustment for HCV treatment initiation compared with untreated patients, patients with SVR had significantly higher 5-year overall survival (87.78% vs. 66.05%, P < 0.001). Multivariable Cox regression showed that SVR was independently associated with a 63% lower risk of 5-year all-cause mortality (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.16-0.83; P = 0.016) and 66% lower risk of 5-year liver-related mortality (HR, 0.34; 95% CI, 0.13-0.88; P = 0.026) with similar trends after removing patients with liver transplants. Landmark analysis at 90, 180, and 360 days showed consistent results (HRs ranged 0.22 to 0.44, all P < 0.05). CONCLUSION: In this multinational consortium, patients with HCV-related HCC who obtained SVR achieved a 60%-70% improvement in 5-year survival (both all-cause and liver related) compared with patients untreated for HCV. Patients eligible for HCC therapy should also be considered for DAA therapy.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular , Hepatite C Crônica , Neoplasias Hepáticas , Ásia/epidemiologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/virologia , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/virologia , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Mortalidade , Inibidores da Transcriptase Reversa/uso terapêutico , Taxa de Sobrevida , Resposta Viral Sustentada , Estados Unidos/epidemiologia
18.
Cities ; 112: 103130, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34812216

RESUMO

Due to COVID-19, Macao established a prolonged tourism lockdown for over half a year. With no COVID-19 cases for 3 months, the lockdown and resilient measures provided the ability to recover, becoming the first city globally to reopen travel borders to all of China. Using the case of Macao during a real-time pandemic crisis we develop a conceptual framework on economic resilience and tourism recovery. We propose for the first-time, destination vulnerabilities as a consequence of recovery and resilient actions. Contrary to government direction that Macao diversify beyond gaming revenues after COVID-19, our study affirms this is unlikely, as casino companies focus on recuperating revenue losses. Our theoretical assertions have wider implications as tourism cities globally look at COVID-19 exit strategies. The short-term resilient endeavors taken now by cities may have longer-term consequences on their 'reset' milieu. With the challenges of vaccination rollout, a COVID-19 exit will be prolonged further with continued economic and tourism recovery challenges for cities, giving greater significant the study's theoretical assertions.

19.
Am J Physiol Lung Cell Mol Physiol ; 319(2): L289-L293, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32491950

RESUMO

When using a new noninvasive method for measuring the efficiency of pulmonary gas exchange, a key measurement is the oxygen deficit, defined as the difference between the end-tidal alveolar Po2 and the calculated arterial Po2. The end-tidal Po2 is measured using a rapid gas analyzer, and the arterial Po2 is derived from pulse oximetry after allowing for the effect of the Pco2 on the oxygen affinity of hemoglobin. In the present report we show that the values of end-tidal Po2 and Pco2 are highly reproducible, providing a solid foundation for the measurement of the oxygen deficit. We compare the oxygen deficit with the classical ideal alveolar-arterial Po2 difference (A-aDO2) as originally proposed by Riley, and now extensively used in clinical practice. This assumes Riley's criteria for ideal alveolar gas, namely no ventilation-perfusion inequality, the same Pco2 as arterial blood, and the same respiratory exchange ratio as the whole lung. It transpires that, in normal subjects, the end-tidal Po2 is essentially the same as the ideal value. This conclusion is consistent with the very small oxygen deficit that we have reported in young normal subjects, the significantly higher values seen in older normal subjects, and the much larger values in patients with lung disease. We conclude that this noninvasive measurement of the efficiency of pulmonary exchange is identical in many respects to that based on the ideal alveolar Po2, but that it is easier to obtain.


Assuntos
Artérias/metabolismo , Pulmão/metabolismo , Oxigênio/metabolismo , Troca Gasosa Pulmonar/fisiologia , Dióxido de Carbono/metabolismo , Hemoglobinas/metabolismo , Humanos , Pulmão/fisiopatologia , Pneumopatias/metabolismo , Pneumopatias/fisiopatologia , Oximetria/métodos , Respiração
20.
Am J Physiol Lung Cell Mol Physiol ; 319(1): L91-L94, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32401675

RESUMO

The oxygen deficit (OD) is the difference between the end-tidal alveolar Po2 and the calculated Po2 of arterial blood based on measured oxygen saturation that acts as a proxy for the alveolar-arterial Po2 difference. Previous work has shown that the alveolar gas meter (AGM100) can measure pulmonary gas exchange, via the OD, in patients with a history of lung disease and in normal subjects breathing 12.5% O2. The present study measured how the OD varied at different values of inspired O2. Healthy subjects were split by age (young 22-31; n = 23; older 42-90; n = 13). Across all inspired O2 levels (12.5, 15, 17.5, and 21%), the OD was higher in the older cohort 10.6 ± 1.0 mmHg compared with the young -0.4 ± 0.6 mmHg (P < 0.0001, using repeated measures ANOVA), the difference being significant at all O2 levels (all P < 0.0001). The OD difference between age groups and its variance was greater at higher O2 values (age × O2 interaction; P = 0.002). The decrease in OD with lower values of inspired O2 in both cohorts is consistent with the increased accuracy of the calculated arterial Po2 based on the O2-Hb dissociation curve and with the expected decrease in the alveolar-arterial Po2 difference due to a lower arterial saturation. The persisting higher OD seen in older subjects, irrespective of the inspired O2, shows that the measurement of OD remains sensitive to mild gas exchange impairment, even when breathing 21% O2.


Assuntos
Oxigênio/administração & dosagem , Oxigênio/metabolismo , Troca Gasosa Pulmonar , Administração por Inalação , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Adulto Jovem
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