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1.
Sci Rep ; 14(1): 15351, 2024 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-38961189

RESUMO

As SARS-CoV-2 continues to spread worldwide, tractable primary airway cell models that recapitulate the cell-intrinsic response to arising viral variants are needed. Here we describe an adult stem cell-derived human airway organoid model overexpressing the ACE2 receptor (ACE2-OE) that supports robust viral replication while maintaining 3D architecture and cellular diversity of the airway epithelium. ACE2-OE organoids were infected with SARS-CoV-2 variants and subjected to single-cell RNA-sequencing. Interferon-lambda was upregulated in cells with low-level infection while the NF-kB inhibitor alpha gene (encoding IkBa) was consistently upregulated in infected cells, and its expression positively correlated with infection levels. Confocal microscopy showed more IkBa expression in infected than bystander cells, but found concurrent nuclear translocation of NF-kB that IkBa usually prevents. Overexpressing a nondegradable IkBa mutant reduced NF-kB translocation and increased viral infection. These data demonstrate the functionality of ACE2-OE organoids in SARS-CoV-2 research and underscore that the strength of the NF-kB feedback loop in infected cells controls viral replication.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Inibidor de NF-kappaB alfa , Organoides , SARS-CoV-2 , Replicação Viral , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/genética , COVID-19/virologia , COVID-19/metabolismo , COVID-19/genética , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Inibidor de NF-kappaB alfa/genética , Organoides/virologia , Organoides/metabolismo , SARS-CoV-2/fisiologia
2.
Annu Rev Biophys ; 53(1): 109-125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39013026

RESUMO

The relationship between genotype and phenotype, or the fitness landscape, is the foundation of genetic engineering and evolution. However, mapping fitness landscapes poses a major technical challenge due to the amount of quantifiable data that is required. Catalytic RNA is a special topic in the study of fitness landscapes due to its relatively small sequence space combined with its importance in synthetic biology. The combination of in vitro selection and high-throughput sequencing has recently provided empirical maps of both complete and local RNA fitness landscapes, but the astronomical size of sequence space limits purely experimental investigations. Next steps are likely to involve data-driven interpolation and extrapolation over sequence space using various machine learning techniques. We discuss recent progress in understanding RNA fitness landscapes, particularly with respect to protocells and machine representations of RNA. The confluence of technical advances may significantly impact synthetic biology in the near future.


Assuntos
RNA Catalítico , RNA Catalítico/química , RNA Catalítico/genética , RNA Catalítico/metabolismo , Evolução Molecular , Aptidão Genética/genética
3.
Acc Chem Res ; 57(15): 2058-2066, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39005057

RESUMO

ConspectusCreating a living system from nonliving matter is a great challenge in chemistry and biophysics. The early history of life can provide inspiration from the idea of the prebiotic "RNA World" established by ribozymes, in which all genetic and catalytic activities were executed by RNA. Such a system could be much simpler than the interdependent central dogma characterizing life today. At the same time, cooperative systems require a mechanism such as cellular compartmentalization in order to survive and evolve. Minimal cells might therefore consist of simple vesicles enclosing a prebiotic RNA metabolism.The internal volume of a vesicle is a distinctive environment due to its closed boundary, which alters diffusion and available volume for macromolecules and changes effective molecular concentrations, among other considerations. These physical effects are mechanistically distinct from chemical interactions, such as electrostatic repulsion, that might also occur between the membrane boundary and encapsulated contents. Both indirect and direct interactions between the membrane and RNA can give rise to nonintuitive, "emergent" behaviors in the model protocell system. We have been examining how encapsulation inside membrane vesicles would affect the folding and activity of entrapped RNA.Using biophysical techniques such as FRET, we characterized ribozyme folding and activity inside vesicles. Encapsulation inside model protocells generally promoted RNA folding, consistent with an excluded volume effect, independently of chemical interactions. This energetic stabilization translated into increased ribozyme activity in two different systems that were studied (hairpin ribozyme and self-aminoacylating RNAs). A particularly intriguing finding was that encapsulation could rescue the activity of mutant ribozymes, suggesting that encapsulation could affect not only folding and activity but also evolution. To study this further, we developed a high-throughput sequencing assay to measure the aminoacylation kinetics of many thousands of ribozyme variants in parallel. The results revealed an unexpected tendency for encapsulation to improve the better ribozyme variants more than worse variants. During evolution, this effect would create a tilted playing field, so to speak, that would give additional fitness gains to already-high-activity variants. According to Fisher's Fundamental Theorem of Natural Selection, the increased variance in fitness should manifest as faster evolutionary adaptation. This prediction was borne out experimentally during in vitro evolution, where we observed that the initially diverse ribozyme population converged more quickly to the most active sequences when they were encapsulated inside vesicles.The studies in this Account have expanded our understanding of emergent protocell behavior, by showing how simply entrapping an RNA inside a vesicle, which could occur spontaneously during vesicle formation, might profoundly affect the evolutionary landscape of the RNA. Because of the exponential dynamics of replication and selection, even small changes to activity and function could lead to major evolutionary consequences. By closely studying the details of minimal yet surprisingly complex protocells, we might one day trace a pathway from encapsulated RNA to a living system.


Assuntos
Células Artificiais , Dobramento de RNA , RNA Catalítico , RNA , Células Artificiais/química , Células Artificiais/metabolismo , RNA Catalítico/química , RNA Catalítico/metabolismo , RNA/química , RNA/metabolismo , Evolução Molecular
4.
Adv Ther (Weinh) ; 7(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38933919

RESUMO

Antimicrobial resistance remains a critical global health concern, necessitating the investigation of alternative therapeutic approaches. With the diminished efficacy of conventional small molecule drugs due to the emergence of highly resilient bacterial strains, there is growing interest in the potential for alternative therapeutic modalities. As naturally occurring viruses of bacteria, bacteriophage (or phage) are being re-envisioned as a platform to engineer properties that can be tailored to target specific bacterial strains and employ diverse antibacterial mechanisms. However, limited understanding of key pharmacological properties of phage is a major challenge to translating its use from preclinical to clinical settings. Here, we review modern advancements in phage-based antimicrobial therapy and discuss the in vivo pharmacokinetics and biodistribution of phage, addressing critical challenges in their application that must be overcome for successful clinical implementation.

5.
Ann Diagn Pathol ; 72: 152323, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38733674

RESUMO

High risk features in colorectal adenomatous polyps include size >1 cm and advanced histology: high-grade dysplasia and villous architecture. We investigated whether the diagnostic rates of advanced histology in colorectal adenomatous polyps were similar among institutions across the United States, and if not, could differences be explained by patient age, polyp size, and/or CRC rate. Nine academic institutions contributed data from three pathologists who had signed out at least 100 colorectal adenomatous polyps each from 2018 to 2019 taken from patients undergoing screening colonoscopy. For each case, we recorded patient age and sex, polyp size and location, concurrent CRC, and presence or absence of HGD and villous features. A total of 2700 polyps from 1886 patients (mean age: 61 years) were collected. One hundred twenty-four (5 %) of the 2700 polyps had advanced histology, including 35 (1 %) with HGD and 101 (4 %) with villous features. The diagnostic rate of advanced histology varied by institution from 1.7 % to 9.3 % (median: 4.3 %, standard deviation [SD]: 2.5 %). The rate of HGD ranged from 0 % to 3.3 % (median: 1 %, SD: 1.2 %), while the rate of villous architecture varied from 1 % to 8 % (median: 3.7 %, SD: 2.5 %). In a multivariate analysis, the factor most strongly associated with advanced histology was polyp size >1 cm with an odds ratio (OR) of 31.82 (95 % confidence interval [CI]: 20.52-50.25, p < 0.05). Inter-institutional differences in the rate of polyps >1 cm likely explain some of the diagnostic variance, but pathologic subjectivity may be another contributing factor.


Assuntos
Pólipos Adenomatosos , Neoplasias Colorretais , Humanos , Pólipos Adenomatosos/patologia , Pólipos Adenomatosos/epidemiologia , Pólipos Adenomatosos/diagnóstico , Pessoa de Meia-Idade , Masculino , Feminino , Neoplasias Colorretais/patologia , Neoplasias Colorretais/epidemiologia , Idoso , Colonoscopia , Pólipos do Colo/patologia , Pólipos do Colo/diagnóstico , Pólipos do Colo/epidemiologia , Adulto , Estados Unidos/epidemiologia , Fatores de Risco
6.
Radiographics ; 44(6): e230126, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38722782

RESUMO

Cardiac tumors, although rare, carry high morbidity and mortality rates. They are commonly first identified either at echocardiography or incidentally at thoracoabdominal CT performed for noncardiac indications. Multimodality imaging often helps to determine the cause of these masses. Cardiac tumors comprise a distinct category in the World Health Organization (WHO) classification of tumors. The updated 2021 WHO classification of tumors of the heart incorporates new entities and reclassifies others. In the new classification system, papillary fibroelastoma is recognized as the most common primary cardiac neoplasm. Pseudotumors including thrombi and anatomic variants (eg, crista terminalis, accessory papillary muscles, or coumadin ridge) are the most common intracardiac masses identified at imaging. Cardiac metastases are substantially more common than primary cardiac tumors. Although echocardiography is usually the first examination, cardiac MRI is the modality of choice for the identification and characterization of cardiac masses. Cardiac CT serves as an alternative in patients who cannot tolerate MRI. PET performed with CT or MRI enables metabolic characterization of malignant cardiac masses. Imaging individualized to a particular tumor type and location is crucial for treatment planning. Tumor terminology changes as our understanding of tumor biology and behavior evolves. Familiarity with the updated classification system is important as a guide to radiologic investigation and medical or surgical management. ©RSNA, 2024 Supplemental material is available for this article.


Assuntos
Neoplasias Cardíacas , Humanos , Ecocardiografia/métodos , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia Computadorizada por Raios X/métodos , Organização Mundial da Saúde
7.
Proc Natl Acad Sci U S A ; 121(13): e2402649121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38478681
8.
BMJ Open ; 14(3): e080751, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38479730

RESUMO

INTRODUCTION: Social robots including telepresence robots have emerged as potential support in dementia care. However, the effectiveness of these robots hinges significantly on their design and utility. These elements are often best understood by their end-users. Codesign involves collaborating directly with the end-users of a product during its development process. Engaging people with dementia in the design of social robots ensures that the products cater to their unique requirements, preferences, challenges, and needs. The objective of this scoping review is to understand the facilitators, barriers, and strategies in codesigning social robots with older adults with dementia. METHODS AND ANALYSIS: The scoping review will follow the Joanna Briggs Institute scoping review methodology and will be conducted from November 2023 to April 2024. The steps of search strategy will involve identifying keywords and index terms from CINAHL and PubMed, completing search using identified keywords and index terms across selected databases (Medline, CINAHL, PubMed, AgeLine, Web of Science, PsycINFO, Scopus, IEEE, and Google Scholar), and hand-searching the reference lists from chosen literature for additional literature. The grey literature will be searched using Google. Three research assistants will screen the titles and abstracts independently by referring to the inclusion criteria. Three researchers will independently assess the full text of literature following to the inclusion criteria. The data will be presented in a table with narratives that answers the questions of the scoping review. ETHICS AND DISSEMINATION: This scoping review does not require ethics approval because it collects data from publicly available resources. The findings will offer insights to inform future research and development of robots through collaboration with older people with dementia. In addition, the scoping review results will be disseminated through conference presentations and an open-access publication in a peer-reviewed journal.


Assuntos
Demência , Robótica , Humanos , Idoso , Projetos de Pesquisa , Interação Social , Bibliometria , Demência/terapia , Literatura de Revisão como Assunto
9.
Virchows Arch ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38499670

RESUMO

Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive malignant neoplasm. Certain histologic features and the tumor microenvironment may impact disease progression. We aim to characterize the clinicopathologic features of ICC to identify prognostic factors. A total of 50 surgically resected ICC (partial or transplant) cases were analyzed. The cohort included 26 men and 24 women with a median age of 62 years. Eighteen (36%) cases were multifocal ICC with a mean largest tumor size of 6.5 cm. Neoadjuvant and adjuvant chemotherapy was done in eight (16%) and 33 (66%) patients, respectively. Histologically, 42 (84%) were small duct type, seven (14%) large duct type, and one mixed (2%). Thirty (60%) cases showed lymphovascular invasion (LVI) and 11 (22%) with perineural invasion (PNI). Twenty-eight (56%) cases demonstrated dense intratumoral hyaline fibrosis and 18 (36%) with tumor necrosis, each ≥ 10% tumor volume. On follow-up, 35 (70%) patients died of disease after a median disease-specific survival (DSS) of 21 months. Univariate analysis revealed that hyaline fibrosis and adjuvant chemotherapy were associated with better DSS, while tumor size, multifocality, necrosis, and peritumoral neutrophil to lymphocyte ratio were associated with worse DSS. In contrast, age, sex, small vs. large duct types, LVI, and individual inflammatory cell counts were not significant prognostic factors. In summary, ICC is a heterogeneous malignancy with variable clinical courses associated with tumor burden, histology, and microenvironment. Targeting specific components within the tumor microenvironments may be a promising approach for treatment in the future.

10.
Sci Rep ; 14(1): 6646, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503831

RESUMO

Nicotine use is a leading cause of preventable deaths worldwide, and most of those who attempt to quit will relapse. While electronic cigarettes and other electronic nicotine delivery systems (ENDS) were presented as a safer alternative to traditional cigarettes and promoted as devices to help traditional tobacco smokers reduce or quit smoking, they have instead contributed to increasing nicotine use among youths. Despite this, ENDS also represent a useful tool to create novel preclinical animal models of nicotine exposure that more accurately represent human nicotine use. In this study, we validated a chronic, intermittent, ENDS-based passive vapor exposure model in mice, and then measured changes in multiple behaviors related to nicotine abstinence. First, we performed a behavioral dose curve to investigate the effects of different nicotine inter-vape intervals on various measures including body weight, locomotor activity, and pain hypersensitivity. Next, we performed a pharmacokinetic study to measure plasma levels of nicotine and cotinine following chronic exposure for each inter-vape interval. Finally, we utilized a behavior test battery at a single dosing regimen that produces blood levels equivalent to human smokers in order to characterize the effects of chronic nicotine, vehicle, or passive airflow and identified nicotine-induced impairments in cognitive behavior.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nicotina , Adolescente , Masculino , Humanos , Camundongos , Animais , Fumar , Cotinina , Gases , Cognição
11.
Methods Mol Biol ; 2793: 175-183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38526731

RESUMO

The filamentous phage M13 is one of the most well-studied and characterized phages, particularly since it was introduced as a scaffold for phage display, a technique to express and evolve fusion proteins on the M13 phage's coat to study protein or peptide binding interactions. Since phages can be engineered or evolved to specifically bind to a variety of targets, engineered M13 phages have been explored for applications such as drug delivery, biosensing, and cancer therapy, among others. Specifically, with the rising challenge of antimicrobial resistance among bacteria, chimeric M13 phages have been explored both as detection and therapeutic agents due to the flexibility in tuning target specificity. Transmission electron microscopy (TEM) is a powerful tool enabling researchers to directly visualize and characterize binding of phages to bacterial surfaces. However, the filamentous phage structure poses a challenge for this technique, as the phages have similar morphology to bacterial structures such as pili. In order to differentiate between bacterial structures and the filamentous phages, here we describe a protocol to prepare TEM samples of engineered M13 phages bound to bacterial cells, in which the phage virions have been specifically labeled by decoration of the major capsid proteins with gold nanoparticles. This protocol enables clear visualization and unambiguous identification of attached filamentous phages within the context of bacterial cells expressing numerous pili.


Assuntos
Inovirus , Nanopartículas Metálicas , Bacteriófago M13/genética , Bacteriófago M13/química , Ouro/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Bactérias/genética
12.
Methods Mol Biol ; 2793: 131-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38526728

RESUMO

Phage-nanomaterial conjugates are functional bio-nanofibers with various applications. While phage display can select for phages with desired genetically encoded functions and properties, nanomaterials can endow the phages with additional features at nanoscale dimensions. Therefore, combining phages with nanotechnology can construct bioconjugates with unique characteristics. One strategy for filamentous phages is to adsorb nanoparticles onto the side wall, composed of pVIII subunits, through electrostatic interactions. However, a noncovalent approach may cause offloading if the environment changes, potentially causing side effects especially for in vivo applications. Therefore, building stable phage-bioconjugates is an important need. We previously reported the construction of chimeric M13 phage conjugated with gold nanorods, named "phanorods," without weakening the binding affinity to the bacterial host cells. Herein, we give a detailed protocol for preparing the chimeric M13 phage and covalently conjugating gold nanorods to the phage.


Assuntos
Inovirus , Nanotubos , Bacteriófago M13/metabolismo , Ouro/química , Técnicas de Visualização da Superfície Celular/métodos
13.
Lupus Sci Med ; 11(1)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38443092

RESUMO

Artificial intelligence and machine learning applications are emerging as transformative technologies in medicine. With greater access to a diverse range of big datasets, researchers are turning to these powerful techniques for data analysis. Machine learning can reveal patterns and interactions between variables in large and complex datasets more accurately and efficiently than traditional statistical methods. Machine learning approaches open new possibilities for studying SLE, a multifactorial, highly heterogeneous and complex disease. Here, we discuss how machine learning methods are rapidly being integrated into the field of SLE research. Recent reports have focused on building prediction models and/or identifying novel biomarkers using both supervised and unsupervised techniques for understanding disease pathogenesis, early diagnosis and prognosis of disease. In this review, we will provide an overview of machine learning techniques to discuss current gaps, challenges and opportunities for SLE studies. External validation of most prediction models is still needed before clinical adoption. Utilisation of deep learning models, access to alternative sources of health data and increased awareness of the ethics, governance and regulations surrounding the use of artificial intelligence in medicine will help propel this exciting field forward.


Assuntos
Inteligência Artificial , Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Aprendizado de Máquina
14.
Hum Pathol ; 144: 40-45, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38307342

RESUMO

The SWItch/Sucrose Non-Fermentable (SWI/SNF) complex is a multimeric protein involved in transcription regulation and DNA damage repair. SWI/SNF complex abnormalities are observed in approximately 14-34 % of pancreatic ductal adenocarcinomas (PDACs). Herein, we evaluated the immunohistochemical expression of a subset of the SWI/SNF complex proteins (ARID1A, SMARCA4/BRG1, SMARCA2/BRM, and SMARCB1/INI1) within our PDAC tissue microarray to determine whether SWI/SNF loss is associated with any clinicopathologic features or patient survival in PDAC. In our cohort, 13 of 353 (3.7 %) PDACs showed deficient SWI/SNF complex expression, which included 11 (3.1 %) with ARID1A loss, 1 (0.3 %) with SMARCA4/BRG1 loss, and 1 (0.3 %) with SMARCA2/BRM loss. All cases were SMARCB1/INI1 proficient. The SWI/SNF-deficient PDACs were more frequently identified in older patients with a mean age of 71.6 years (SD = 7.78) compared to the SWI/SNF-proficient PDACs which occurred at a mean age of 65.2 years (SD = 10.95) (P = 0.013). The SWI/SNF-deficient PDACs were associated with higher histologic grade, compared to the SWI/SNF-proficient PDACs (P = 0.029). No other significant clinicopathologic differences were noted between SWI/SNF-deficient and SWI/SNF-proficient PDACs. On follow-up, no significant differences were seen for overall survival and progression-free survival between SWI/SNF-deficient and SWI/SNF-proficient PDACs (both with P > 0.05). In summary, SWI/SNF-deficient PDACs most frequently demonstrate ARID1A loss. SWI/SNF-deficient PDACs are associated with older age and higher histologic grade. No other significant associations among other clinicopathologic parameters were seen in SWI/SNF-deficient PDACs including survival.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Idoso , Montagem e Desmontagem da Cromatina , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
15.
Res Sq ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38352503

RESUMO

Nicotine use is a leading cause of preventable deaths worldwide, and most of those who attempt to quit will relapse. While electronic cigarettes and other electronic nicotine delivery systems (ENDS) were presented as a safer alternative to traditional cigarettes and promoted as devices to help traditional tobacco smokers reduce or quit smoking, they have instead contributed to increasing nicotine use among youths. Despite this, ENDS also represent a useful tool to create novel preclinical animal models of nicotine exposure that more accurately represent human nicotine use. In this study, we validated a chronic, intermittent, ENDS-based passive vapor exposure model in mice, and then measured changes in multiple behaviors related to nicotine abstinence. First, we performed a behavioral dose curve to investigate the effects of different nicotine inter-vape intervals on various measures including body weight, locomotor activity, and pain hypersensitivity. Next, we performed a pharmacokinetic study to measure plasma levels of nicotine and cotinine following chronic exposure for each inter-vape interval. Finally, we utilized a behavior test battery at a single dosing regimen that produces blood levels equivalent to human smokers in order to characterize the effects of chronic nicotine, vehicle, or passive airflow and identified nicotine-induced impairments in cognitive behavior.

18.
bioRxiv ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38293112

RESUMO

Synthetic and chimeric receptors capable of recognizing and responding to user-defined antigens have enabled "smart" therapeutics based on engineered cells. These cell engineering tools depend on antigen sensors which are most often derived from antibodies. Advances in the de novo design of proteins have enabled the design of protein binders with the potential to target epitopes with unique properties and faster production timelines compared to antibodies. Building upon our previous work combining a de novo-designed minibinder of the Spike protein of SARS-CoV-2 with the synthetic receptor synNotch (SARSNotch), we investigated whether minibinders can be readily adapted to a diversity of cell engineering tools. We show that the Spike minibinder LCB1 easily generalizes to a next-generation proteolytic receptor SNIPR that performs similarly to our previously reported SARSNotch. LCB1-SNIPR successfully enables the detection of live SARS-CoV-2, an improvement over SARSNotch which can only detect cell-expressed Spike. To test the generalizability of minibinders to diverse applications, we tested LCB1 as an antigen sensor for a chimeric antigen receptor (CAR). LCB1-CAR enabled CD8+ T cells to cytotoxically target Spike-expressing cells. Our findings suggest that minibinders represent a novel class of antigen sensors that have the potential to dramatically expand the sensing repertoire of cell engineering tools.

19.
Biophys J ; 123(4): 451-463, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37924206

RESUMO

One of the earliest living systems was likely based on RNA ("the RNA world"). Mineral surfaces have been postulated to be an important environment for the prebiotic chemistry of RNA. In addition to adsorbing RNA and thus potentially reducing the chance of parasitic takeover through limited diffusion, minerals have been shown to promote a range of processes related to the emergence of life, including RNA polymerization, peptide bond formation, and self-assembly of vesicles. In addition, self-cleaving ribozymes have been shown to retain activity when adsorbed to the clay mineral montmorillonite. However, simulation studies suggest that adsorption to minerals is likely to interfere with RNA folding and, thus, function. To further evaluate the plausibility of a mineral-adsorbed RNA world, here we studied the effect of the synthetic clay montmorillonite K10 on the malachite green RNA aptamer, including binding of the clay to malachite green and RNA, as well as on the formation of secondary structures in model RNA and DNA oligonucleotides. We evaluated the fluorescence of the aptamer complex, adsorption to the mineral, melting curves, Förster resonance energy transfer interactions, and 1H-NMR signals to study the folding and functionality of these nucleic acids. Our results indicate that while some base pairings are unperturbed, the overall folding and binding of the malachite green aptamer are substantially disrupted by montmorillonite. These findings suggest that minerals would constrain the structures, and possibly the functions, available to an adsorbed RNA world.


Assuntos
Bentonita , RNA , Corantes de Rosanilina , Bentonita/química , RNA/química , Argila , Silicatos de Alumínio/química , Adsorção , Minerais/química
20.
Urology ; 184: 94-100, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38160761

RESUMO

OBJECTIVE: To assess the incidence, cumulative healthcare burden, and financial impact of inpatient admissions for radiation cystitis (RC), while exploring practice differences in RC management between teaching and nonteaching hospitals. METHODS: We focused on 19,613 patients with a diagnosis of RC within the National Inpatient Sample (NIS) from 2008 to 2014. ICD-9 diagnosis and procedure codes were used. Complex-survey procedures were used to study the descriptive characteristics of RC patients and the procedures received during admission, stratified by hospital teaching status. Inflation-adjusted cost and cumulative annual cost were calculated for the study period. Multivariable logistic regression was used to study the impact of teaching status on the high total cost of admission. RESULTS: Median age was 76 (interquartile range 67-82) years. Most of the patients were males (73%; P < .001). 59,571 (61%) patients received at least one procedure, of which, 24,816 (25.5%) received more than one procedure. Median length of stay was 5days (interquartile range 2-9). Female patients and patients with a higher comorbidity score were more frequently treated at teaching hospitals. A higher proportion of patients received a procedure at a teaching hospital (64% vs 59%; P < .001). The inflation-adjusted cost was 9207 USD and was higher in teaching hospitals. The cumulative cost of inpatient treatment of RC was 63.5 million USD per year and 952.2 million USD over the study period. CONCLUSION: The incidence of RC-associated admissions is rising in the US. This disease is a major burden to US healthcare. The awareness of the inpatient economic burden and healthcare utilization associated with RC may have funding implications.


Assuntos
Cistite , Pacientes Internados , Masculino , Humanos , Estados Unidos/epidemiologia , Feminino , Idoso , Idoso de 80 Anos ou mais , Hospitais de Ensino , Custos Hospitalares , Cistite/epidemiologia , Cistite/terapia , Aceitação pelo Paciente de Cuidados de Saúde
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