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1.
Am J Pathol ; 192(6): 917-925, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35390316

RESUMO

Rhabdomyosarcoma (RMS), the most common malignant soft tissue tumor in children, has several histologic subtypes that influence treatment and predict patient outcomes. Assistance with histologic classification for pathologists as well as discovery of optimized predictive biomarkers is needed. A convolutional neural network for RMS histology subtype classification was developed using digitized pathology images from 80 patients collected at time of diagnosis. A subsequent embryonal rhabdomyosarcoma (eRMS) prognostic model was also developed in a cohort of 60 eRMS patients. The RMS classification model reached a performance of an area under the receiver operating curve of 0.94 for alveolar rhabdomyosarcoma and an area under the receiver operating curve of 0.92 for eRMS at slide level in the test data set (n = 192). The eRMS prognosis model separated the patients into predicted high- and low-risk groups with significantly different event-free survival outcome (likelihood ratio test; P = 0.02) in the test data set (n = 136). The predicted risk group is significantly associated with patient event-free survival outcome after adjusting for patient age and sex (predicted high- versus low-risk group hazard ratio, 4.64; 95% CI, 1.05-20.57; P = 0.04). This is the first comprehensive study to develop computational algorithms for subtype classification and prognosis prediction for RMS histopathology images. Such models can aid pathology evaluation and provide additional parameters for risk stratification.


Assuntos
Aprendizado Profundo , Rabdomiossarcoma Embrionário , Rabdomiossarcoma , Criança , Intervalo Livre de Doença , Humanos , Prognóstico , Rabdomiossarcoma/diagnóstico por imagem , Rabdomiossarcoma/patologia , Rabdomiossarcoma Embrionário/patologia
2.
New Phytol ; 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38073143

RESUMO

Rising atmospheric carbon dioxide concentrations (CO2 ) and atmospheric nitrogen (N) deposition have contrasting effects on ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) symbioses, potentially mediating forest responses to environmental change. In this study, we evaluated the cumulative effects of historical environmental change on N concentrations and δ15 N values in AM plants, EM plants, EM fungi, and saprotrophic fungi using herbarium specimens collected in Minnesota, USA from 1871 to 2016. To better understand mycorrhizal mediation of foliar δ15 N, we also analyzed a subset of previously published foliar δ15 N values from across the United States to parse the effects of N deposition and CO2 rise. Over the last century in Minnesota, N concentrations declined among all groups except saprotrophic fungi. δ15 N also declined among all groups of plants and fungi; however, foliar δ15 N declined less in EM plants than in AM plants. In the analysis of previously published foliar δ15 N values, this slope difference between EM and AM plants was better explained by nitrogen deposition than by CO2 rise. Mycorrhizal type did not explain trajectories of plant N concentrations. Instead, plants and EM fungi exhibited similar declines in N concentrations, consistent with declining forest N status despite moderate levels of N deposition.

3.
J Thromb Thrombolysis ; 55(2): 355-364, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36564588

RESUMO

The few studies that compared direct oral anticoagulants (DOAC) vs. warfarin in the setting of advanced renal insufficiency have focused on patients with atrial fibrillation. The purpose of this observational, matched, cohort study of patients was to assess the effectiveness and safety of DOAC vs. warfarin for the treatment of venous thromboembolism (VTE) among patients with a creatinine clearance (CrCl) < 30 mL/min. This observational, cohort study included patients with VTE and CrCl < 30 mL/min who were newly initiated on a DOAC or warfarin between January 1, 2016 and December 31, 2020. DOAC patients were matched up to 1:2 to warfarin patients. Primary outcome was a composite of recurrent VTE, clinically-relevant bleeding, ischemic stroke, and all-cause mortality. Adjusted conditional, multivariate Cox proportional hazards modeling was used to assess outcomes. 626 DOAC patients were matched to 1071 warfarin patients. DOAC patients had a higher mean age, higher mean baseline CrCl, and were less likely to have been receiving dialysis. There was no statistically significant difference in the composite outcome between groups (adjusted hazard ratio [aHR] 1.13, 95% confidence interval [CI] 0.87-1.47) or in the individual components of the composite (all HR 95% CI crossed 1.00). Identification of statistically non-significant rates of bleeding and thromboembolic outcomes suggest that the use of DOAC or warfarin is reasonable in patients with VTE and CrCl < 30 mL/min.


Assuntos
Fibrilação Atrial , Tromboembolia Venosa , Humanos , Varfarina/efeitos adversos , Anticoagulantes/efeitos adversos , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/induzido quimicamente , Creatinina , Estudos de Coortes , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Fibrilação Atrial/tratamento farmacológico , Administração Oral , Estudos Retrospectivos
4.
Plant Biotechnol J ; 20(11): 2135-2148, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35869808

RESUMO

Improving biological nitrogen fixation (BNF) in cereal crops is a long-sought objective; however, no successful modification of cereal crops showing increased BNF has been reported. Here, we described a novel approach in which rice plants were modified to increase the production of compounds that stimulated biofilm formation in soil diazotrophic bacteria, promoted bacterial colonization of plant tissues and improved BNF with increased grain yield at limiting soil nitrogen contents. We first used a chemical screening to identify plant-produced compounds that induced biofilm formation in nitrogen-fixing bacteria and demonstrated that apigenin and other flavones induced BNF. We then used CRISPR-based gene editing targeting apigenin breakdown in rice, increasing plant apigenin contents and apigenin root exudation. When grown at limiting soil nitrogen conditions, modified rice plants displayed increased grain yield. Biofilm production also modified the root microbiome structure, favouring the enrichment of diazotrophic bacteria recruitment. Our results support the manipulation of the flavone biosynthetic pathway as a feasible strategy for the induction of biological nitrogen fixation in cereals and a reduction in the use of inorganic nitrogen fertilizers.


Assuntos
Fixação de Nitrogênio , Oryza , Fixação de Nitrogênio/genética , Oryza/metabolismo , Solo , Edição de Genes , Apigenina/metabolismo , Fertilizantes , Produtos Agrícolas , Bactérias/genética , Nitrogênio/metabolismo , Grão Comestível/metabolismo , Biofilmes
5.
Antonie Van Leeuwenhoek ; 115(9): 1215-1228, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35920985

RESUMO

Strain OCN044T was isolated from the homogenised tissue and mucus of an apparently healthy Acropora cytherea coral fragment collected from the western reef terrace of Palmyra Atoll in the Northern Line Islands and was taxonomically evaluated with a polyphasic approach. The morphological and chemotaxonomic properties are consistent with characteristics of the genus Vibrio: Gram-stain-negative rods, oxidase- and catalase-positive, and motile by means of a polar flagellum. Strain OCN044T can be differentiated as a novel subspecies based on 21 differences among chemotaxonomic features (e.g., fatty acids percentages for C12:0 and C18:1 ω7c), enzymatic activities (e.g., DNase and cystine arylamidase), and carbon sources utilized (e.g., L-xylose and D-melezitose) from its nearest genetic relative. Phylogenetic analysis and genomic comparisons show close evolutionary relatedness to Vibrio tetraodonis A511T but the overall genomic relatedness indices identify strain OCN044T as a distinct subspecies. Based on a polyphasic characterisation, differences in genomic and taxonomic data, strain OCN044T represents a novel subspecies of V. tetraodonis A511T, for which the name Vibrio tetraodonis subsp. pristinus subsp. nov. is proposed. The type strain is OCN044T (= LMG 31895T = DSM 111778T).


Assuntos
Antozoários , Vibrio , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Ecology ; 99(1): 204-216, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29106700

RESUMO

It is commonly assumed that microbial communities are structured by "bottom-up" ecological forces, although few experimental manipulations have rigorously tested the mechanisms by which resources structure soil communities. We investigated how plant substrate availability might structure fungal communities and belowground processes along an experimental plant richness gradient in a grassland ecosystem. We hypothesized that variation in total plant-derived substrate inputs, plant functional group diversity, as well as the relative abundance of C4 grasses and legumes would modulate fungal α- and ß-diversity and their rates of soil carbon (C) and nitrogen (N) cycling. To test these predictions, we molecularly characterized fungal communities, as well as potential extracellular enzyme activity, net N mineralization, and soil organic matter respiration. We found higher fungal richness was associated with increasing aboveground plant biomass; whereas, fungal ß-diversity was explained by contributions from C4 grass and legume relative dominance, plant functional group diversity, as well as plant biomass. Furthermore, aboveground plant biomass consistently shaped the richness and composition of individual fungal trophic modes (i.e., saprotrophs, symbiotrophs, pathotrophs). Finally, variation in extracellular enzyme activity, net N mineralization rates, and soil organic matter respiration was significantly explained by fungal ß-diversity when fungi were functionally classified. Via changes in the supply and composition of organic substrates entering soil, our study demonstrates that changes in the plant species richness and functional composition collectively influence fungal communities and rates of soil C and N cycling.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Biomassa , Fungos , Solo/química , Microbiologia do Solo
7.
Ecol Lett ; 20(2): 202-211, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28111902

RESUMO

Foraging intensity of large herbivores may exert an indirect top-down ecological force on soil microbial communities via changes in plant litter inputs. We investigated the responses of the soil microbial community to elk (Cervus elaphus) winter range occupancy across a long-term foraging exclusion experiment in the sagebrush steppe of the North American Rocky Mountains, combining phylogenetic analysis of fungi and bacteria with shotgun metagenomics and extracellular enzyme assays. Winter foraging intensity was associated with reduced bacterial richness and increasingly distinct bacterial communities. Although fungal communities did not respond linearly to foraging intensity, a greater ß-diversity response to winter foraging exclusion was observed. Furthermore, winter foraging exclusion increased soil cellulolytic and hemicellulolytic enzyme potential and higher foraging intensity reduced chitinolytic gene abundance. Thus, future changes in winter range occupancy may shape biogeochemical processes via shifts in microbial communities and subsequent changes to their physiological capacities to cycle soil C and N.


Assuntos
Fenômenos Fisiológicos Bacterianos , Ciclo do Carbono , Cervos/fisiologia , Fungos/fisiologia , Herbivoria , Ciclo do Nitrogênio , Microbiologia do Solo , Animais , Artemisia/crescimento & desenvolvimento , Bactérias/genética , Fungos/genética , Pradaria , Estações do Ano , Solo/química , Wyoming
8.
Mol Ecol ; 24(19): 5045-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26331892

RESUMO

Priority effects are an important ecological force shaping biotic communities and ecosystem processes, in which the establishment of early colonists alters the colonization success of later-arriving organisms via competitive exclusion and habitat modification. However, we do not understand which biotic and abiotic conditions lead to strong priority effects and lasting historical contingencies. Using saprotrophic fungi in a model leaf decomposition system, we investigated whether compositional and functional consequences of initial colonization were dependent on initial colonizer traits, resource availability or a combination thereof. To test these ideas, we factorially manipulated leaf litter biochemistry and initial fungal colonist identity, quantifying subsequent community composition, using neutral genetic markers, and community functional characteristics, including enzyme potential and leaf decay rates. During the first 3 months, initial colonist respiration rate and physiological capacity to degrade plant detritus were significant determinants of fungal community composition and leaf decay, indicating that rapid growth and lignolytic potential of early colonists contributed to altered trajectories of community assembly. Further, initial colonization on oak leaves generated increasingly divergent trajectories of fungal community composition and enzyme potential, indicating stronger initial colonizer effects on energy-poor substrates. Together, these observations provide evidence that initial colonization effects, and subsequent consequences on litter decay, are dependent upon substrate biochemistry and physiological traits within a regional species pool. Because microbial decay of plant detritus is important to global C storage, our results demonstrate that understanding the mechanisms by which initial conditions alter priority effects during community assembly may be key to understanding the drivers of ecosystem-level processes.


Assuntos
Biota , Ecossistema , Fungos/classificação , Microbiologia do Solo , DNA Fúngico/genética , Fungos/fisiologia , Folhas de Planta/química , Folhas de Planta/microbiologia , Análise de Sequência de DNA , Solo/química , Árvores
9.
Ecology ; 96(12): 3374-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26909442

RESUMO

Although we understand the ecological processes eliciting changes in plant community composition during secondary succession, we do not understand whether co-occurring changes in plant detritus shape saprotrophic microbial communities in soil. In this study, we investigated soil microbial composition and function across an old-field chronosequence ranging from 16 to 86 years following agricultural abandonment, as well as three forests representing potential late-successional ecosystems. Fungal and bacterial community composition was quantified from ribosomal DNA, and insight into the functional potential of the microbial community to decay plant litter was gained from shotgun metagenomics and extracellular enzyme assays. Accumulation of soil organic matter across the chronosequence exerted a positive and significant effect on fungal phylogenetic ß-diversity and the activity of extracellular enzymes with lignocellulolytic activity. In addition, the increasing abundance of lignin-rich C4 grasses was positively related to the composition of fungal genes with lignocellulolytic function, thereby linking plant community composition, litter biochemistry, and microbial community function. However, edaphic properties were the primary agent shaping bacterial communities, as bacterial ß-diversity and variation in functional gene composition displayed a significant and positive relationship to soil pH across the chronosequence. The late-successional forests were compositionally distinct from the oldest old fields, indicating that substantial changes occur in soil microbial communities as old fields give way to forests. Taken together, our observations demonstrate that plants govern the turnover of soil fungal communities and functional characteristics during secondary succession, due to the continual input of detritus and differences in litter biochemistry among plant species.


Assuntos
Bactérias/classificação , Ecossistema , Fungos/classificação , Fenômenos Fisiológicos Vegetais , Microbiologia do Solo , Bactérias/genética , Fungos/genética , Concentração de Íons de Hidrogênio , Minnesota , Filogenia , Solo/química
10.
Ecology ; 96(9): 2383-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26594696

RESUMO

Saprotrophic microbial communities in soil are primarily structured by the availability of growth-limiting resources (i.e., plant detritus), a bottom-up ecological force. However, foraging by native ungulates can alter plant community composition and the nature of detritus entering soil, plausibly exerting an indirect, top-down ecological force that shapes both the composition and function of soil microbial communities. To test this idea, we used physiological assays and molecular approaches to quantify microbial community composition and function inside and outside of replicate, long-term (60-80 yr) winter-foraging exclosures in sagebrush steppe of Wyoming, USA. Winter foraging exclusion substantially increased shrub biomass (2146 g/m2 vs. 87 g/m2), which, in turn, increased the abundance of bacterial and fungal genes with lignocellulolytic function; microbial respiration (+50%) and net N mineralization (+70%) also were greater in the absence of winter foraging. Our results reveal that winter foraging by native, migratory ungulates in sagebrush steppe exerts an indirect, top-down ecological force that shapes the composition and function of soil microbial communities. Because approximately 25% of the Earth's land surface is influenced by grazing animals, this indirect top-down ecological force could function to broadly shape the community membership and physiological capacity of saprotrophic microbial communities in shrub steppe.


Assuntos
Artemisia/fisiologia , Bactérias/classificação , Cervos/fisiologia , Fungos/classificação , Microbiologia do Solo , Animais , Artemisia/crescimento & desenvolvimento , Bactérias/metabolismo , Biomarcadores , Fungos/metabolismo , Herbivoria , Estações do Ano
11.
Environ Microbiol ; 16(6): 1538-48, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24119055

RESUMO

Microbial communities in soil mediate biogeochemical processes; however, understanding forces shaping their composition and function remains a gap in our ecological knowledge. We investigated phylogenetic turnover and functional gene composition of saprotrophic fungi along a 4000-year glacial chronosequence. A direct relationship between ß-diversity and geographic distance, a proxy for time since deglaciation, indicated that dispersal limitation shapes saprotrophic fungal communities. Further, we infer that dispersal limitation may also influence fungal functional properties as metabolic potential and functional richness increased with site age. Despite attempts to minimize environmental variation, a direct relationship between ß-diversity and biogeochemical differences across sites indicated that environmental filtering further shapes fungal community composition. However, environmental filtering was overshadowed by the effect of dispersal limitation when tested by multiple regression. Fungal ß-diversity and composition of functional genes involved in plant litter decay were unrelated, suggesting that functional traits are not phylogenetically conserved across this chronosequence. Our study suggests that dispersal limitation operates in structuring present-day fungal community composition and functional potential. Further, we demonstrate the need to integrate functional and phylogenetic approaches to more accurately portray microbial communities and their functional capacities.


Assuntos
Fungos/genética , Microbiologia do Solo , Biodiversidade , Variação Genética , Camada de Gelo , Filogenia
12.
Bioconjug Chem ; 25(2): 197-201, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24433067

RESUMO

The synthesis, computer modeling, and biological activity of an octawalled molecular umbrella short interfacing RNA (siRNA) conjugate is described. This molecular umbrella-siRNA conjugate exhibited mRNA knockdown activity in vitro in the absence of a transfection reagent. Evaluation of this molecular umbrella conjugate in vivo, using the rat eye via intravitreal injection, resulted in sequence specific mRNA knockdown in the retina with no obvious signs of toxicity, as judged by ophthalmic examination.


Assuntos
Portadores de Fármacos , Olho , RNA Interferente Pequeno/administração & dosagem , Vias de Administração de Medicamentos , Células HEK293 , Humanos , Simulação de Dinâmica Molecular
13.
Front Plant Sci ; 15: 1332840, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545390

RESUMO

Potato (Solanum tuberosum L.) is considered one of the most widely consumed crops worldwide, due to its high yield and nutritional profile, climate change-related environmental threats and increasing food demand. This scenario highlights the need of sustainable agricultural practices to enhance potato productivity, while preserving and maintaining soil health. Plant growth-promoting bacteria (PGPB) stimulate crop production through biofertilization mechanisms with low environmental impact. For instance, PGPB promote biological nitrogen fixation, phosphate solubilization, production of phytohormones, and biocontrol processes. Hence, these microbes provide a promising solution for more productive and sustainable agriculture. In this study, the effects of Bacillus amyloliquefaciens QST713 based-product (MINUET™, Bayer) were assessed in terms of yield, soil microbiome, potato peel and petiole nutrient profile as a promising PGPB in a wide range of potato cultivars across the United States of America. Depending on the location, potato yield and boron petiole content increased after biostimulant inoculation to maximum of 24% and 14%, respectively. Similarly, nutrient profile in potato peel was greatly improved depending on the location with a maximum of 73%, 62% and 36% for manganese, zinc and phosphorus. Notably, fungal composition was shifted in the treated group. Yield showed strong associations with specific microbial taxa, such as Pseudoarthrobacter, Ammoniphilus, Ideonella, Candidatus Berkiella, Dongia. Moreover, local networks strongly associated with yield, highlighting the important role of the native soil microbiome structure in indirectly maintaining soil health. Our results showed that treatment with B. amyloliquefaciens based product correlated with enhanced yield, with minor impacts on the soil microbiome diversity. Further studies are suggested to disentangle the underlying mechanisms of identified patterns and associations.

15.
Analyst ; 138(15): 4305-11, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23785707

RESUMO

A strategy was developed to extend the lifetime of an peptide-based substrate for Abl kinase in the cytosolic environment. Small ß-turn structures were added to the peptide's N-terminus to block entry into peptidase catalytic sites. The influence of the size of the ß-turn and two covalent cross-linking strategies on the rate of hydrolysis was assessed. The most peptidase-resistant substrate was degraded at a rate of 0.6 pmol mg(-1) s(-1) and possessed a half-life of 20.3 ± 1.7 min in a Baf/BCR-ABL cytosolic lysate, representing 16- and 40-fold improvements, respectively, over that of a control peptide lacking the ß-turn structure. Furthermore, the kcat/KM value of this peptide was 432 µM(-1) min(-1), a 1.25× increase over the unmodified control, verifying that the added ß-turn did not hinder the substrate properties of the peptide. This improved peptide was microinjected into single Baf/BCR-ABL cells and substrate phosphorylation measured. Zero to forty percent of the peptide was phosphorylated in the single cells. In contrast, when the control peptide without a ß-turn was loaded into cells, the peptide was too rapidly degraded to detect phosphorylation. This work demonstrates that small ß-turn structures can render peptides more resistant to hydrolysis while retaining substrate efficacy and shows that these stabilized peptides have the potential to be of high utility in single-cell enzyme assays.


Assuntos
Citosol/química , Citosol/enzimologia , Proteínas de Fusão bcr-abl/química , Fragmentos de Peptídeos/química , Animais , Linhagem Celular Tumoral , Proteínas de Fusão bcr-abl/genética , Camundongos , Fragmentos de Peptídeos/genética , Peptídeos/química , Peptídeos/genética , Especificidade por Substrato/genética
16.
JCO Clin Cancer Inform ; 7: e2300104, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37956387

RESUMO

PURPOSE: Osteosarcoma research advancement requires enhanced data integration across different modalities and sources. Current osteosarcoma research, encompassing clinical, genomic, protein, and tissue imaging data, is hindered by the siloed landscape of data generation and storage. MATERIALS AND METHODS: Clinical, molecular profiling, and tissue imaging data for 573 patients with pediatric osteosarcoma were collected from four public and institutional sources. A common data model incorporating standardized terminology was created to facilitate the transformation, integration, and load of source data into a relational database. On the basis of this database, a data commons accompanied by a user-friendly web portal was developed, enabling various data exploration and analytics functions. RESULTS: The Osteosarcoma Explorer (OSE) was released to the public in 2021. Leveraging a comprehensive and harmonized data set on the backend, the OSE offers a wide range of functions, including Cohort Discovery, Patient Dashboard, Image Visualization, and Online Analysis. Since its initial release, the OSE has experienced an increasing utilization by the osteosarcoma research community and provided solid, continuous user support. To our knowledge, the OSE is the largest (N = 573) and most comprehensive research data commons for pediatric osteosarcoma, a rare disease. This project demonstrates an effective framework for data integration and data commons development that can be readily applied to other projects sharing similar goals. CONCLUSION: The OSE offers an online exploration and analysis platform for integrated clinical, molecular profiling, and tissue imaging data of osteosarcoma. Its underlying data model, database, and web framework support continuous expansion onto new data modalities and sources.


Assuntos
Gerenciamento de Dados , Osteossarcoma , Criança , Humanos , Bases de Dados Factuais , Genômica , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/genética
18.
Bioconjug Chem ; 23(3): 336-9, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22372891

RESUMO

PEGylated phospholipids are commonly used to increase the blood-circulation time of liposomes by providing a steric barrier around them. This paper documents a fundamentally new property of these lipids-an ability to stimulate the release of cholesterol from phospholipid membranes. Evidence for such stimulation has been obtained by measuring the transport of dehydroergosterol (DHE), a fluorescent simulant of cholesterol, from donor liposomes made from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000 (DSPE-PEG(2000)), and DHE to acceptor liposomes made from POPC, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG), and cholesterol. The potential of PEGylated lipids to serve as novel cholesterol-lowering agents is briefly discussed.


Assuntos
Colesterol/química , Lipossomos , Membranas Artificiais , Fosfolipídeos/química , Polietilenoglicóis/química
19.
Perm J ; 26(3): 128-134, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35939606

RESUMO

IntroductionCerebral venous sinus thrombosis (CVST) is a rare neurovascular emergency that has been observed following COVID-19 infection, as well as following the use of non-mRNA COVID-19 vaccines. Case PresentationThe authors report a case of CVST in a 67-year-old woman, unvaccinated for COVID-19, who presented with acute otitis externa. It remains unclear whether the CVST was a following COVID-19 infection complication, otogenic CVST, or a combination of both. ConclusionThis case demonstrates the diagnostic and therapeutic dilemmas in managing this patient's challenging anticoagulation and antibiotic duration, as well as subsequent COVID-19 vaccination recommendations.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Trombose dos Seios Intracranianos , Idoso , Antibacterianos/uso terapêutico , Anticoagulantes/uso terapêutico , Teste para COVID-19 , Vacinas contra COVID-19/efeitos adversos , Feminino , Humanos , RNA Mensageiro , Trombose dos Seios Intracranianos/diagnóstico , Trombose dos Seios Intracranianos/tratamento farmacológico , Trombose dos Seios Intracranianos/etiologia , Vacinação/efeitos adversos
20.
Bioconjug Chem ; 22(11): 2210-6, 2011 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-21985221

RESUMO

A series of diwalled and tetrawalled molecular umbrellas have been synthesized using cholic acid, spermidine, and lysine as starting materials. Coupling of these molecular umbrellas to an octaarginine peptide afforded agents that were capable of promoting the transport of small interfering RNA to HeLa cells, as judged by the knockdown of enhanced green fluorescent protein expression. The efficiency of this knockdown was found to increase with an increasing number of facially amphiphilic walls present, and also when a cleavable disulfide linker was replaced with a noncleavable, maleimido moiety; i.e., a group that is not susceptible to thiolate-disulfide interchange. The knockdown efficiency that was observed for one tetrawalled molecular umbrella-octaargine conjugate was comparable to that observed with a commercially available transfection agent, Lipofectamine 2000, but the conjugate showed less cytotoxicity.


Assuntos
Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , RNA Interferente Pequeno/metabolismo , Portadores de Fármacos/síntese química , Células HeLa , Humanos , Estrutura Molecular , Peptídeos/síntese química , RNA Interferente Pequeno/química
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