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1.
J Extracell Vesicles ; 11(10): e12220, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36214496

RESUMO

One of the functions of small extracellular vesicles (sEVs) which has received the most attention is their capacity to deliver RNA into the cytoplasm of target cells. These studies have often been performed by transfecting RNAs into sEV-producing cells, to later purify and study sEV delivery of RNA. Transfection complexes and other delivery vehicles accumulate in late endosomes where sEV are formed and over 50% of transfection complexes or delivery vehicles administered to cells are released again to the extracellular space by exocytosis. This raises the possibility that transfection complexes could alter sEVs and contaminate sEV preparations. We found that widely used transfection reagents including RNAiMax and INTERFERin accumulated in late endosomes. These transfection complexes had a size similar to sEV and were purified by ultracentrifugation like sEV. Focusing on the lipid-based transfection reagent RNAiMax, we found that preparations of sEV from transfected cells contained lipids from transfection complexes and transfected siRNA was predominantly in particles with the density of transfection complexes, rather than sEV. This suggests that transfection complexes, such as lipid-based RNAiMax, may frequently contaminate sEV preparations and could account for some reports of sEV-mediated delivery of nucleic acids. Transfection of cells also impaired the capacity of sEVs to deliver stably-expressed siRNAs, suggesting that transfection of cells may alter sEVs and prevent the study of their endogenous capacity to deliver RNA to target cells.


Assuntos
Vesículas Extracelulares , Lipídeos , RNA Interferente Pequeno , Transfecção , Ultracentrifugação
2.
Commun Med (Lond) ; 2: 128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36249461

RESUMO

Background: Fetal ultrasound is an important component of antenatal care, but shortage of adequately trained healthcare workers has limited its adoption in low-to-middle-income countries. This study investigated the use of artificial intelligence for fetal ultrasound in under-resourced settings. Methods: Blind sweep ultrasounds, consisting of six freehand ultrasound sweeps, were collected by sonographers in the USA and Zambia, and novice operators in Zambia. We developed artificial intelligence (AI) models that used blind sweeps to predict gestational age (GA) and fetal malpresentation. AI GA estimates and standard fetal biometry estimates were compared to a previously established ground truth, and evaluated for difference in absolute error. Fetal malpresentation (non-cephalic vs cephalic) was compared to sonographer assessment. On-device AI model run-times were benchmarked on Android mobile phones. Results: Here we show that GA estimation accuracy of the AI model is non-inferior to standard fetal biometry estimates (error difference -1.4 ± 4.5 days, 95% CI -1.8, -0.9, n = 406). Non-inferiority is maintained when blind sweeps are acquired by novice operators performing only two of six sweep motion types. Fetal malpresentation AUC-ROC is 0.977 (95% CI, 0.949, 1.00, n = 613), sonographers and novices have similar AUC-ROC. Software run-times on mobile phones for both diagnostic models are less than 3 s after completion of a sweep. Conclusions: The gestational age model is non-inferior to the clinical standard and the fetal malpresentation model has high AUC-ROCs across operators and devices. Our AI models are able to run on-device, without internet connectivity, and provide feedback scores to assist in upleveling the capabilities of lightly trained ultrasound operators in low resource settings.

3.
Commun Med (Lond) ; 2: 40, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603304

RESUMO

Background: Measuring vital signs plays a key role in both patient care and wellness, but can be challenging outside of medical settings due to the lack of specialized equipment. Methods: In this study, we prospectively evaluated smartphone camera-based techniques for measuring heart rate (HR) and respiratory rate (RR) for consumer wellness use. HR was measured by placing the finger over the rear-facing camera, while RR was measured via a video of the participants sitting still in front of the front-facing camera. Results: In the HR study of 95 participants (with a protocol that included both measurements at rest and post exercise), the mean absolute percent error (MAPE) ± standard deviation of the measurement was 1.6% ± 4.3%, which was significantly lower than the pre-specified goal of 5%. No significant differences in the MAPE were present across colorimeter-measured skin-tone subgroups: 1.8% ± 4.5% for very light to intermediate, 1.3% ± 3.3% for tan and brown, and 1.8% ± 4.9% for dark. In the RR study of 50 participants, the mean absolute error (MAE) was 0.78 ± 0.61 breaths/min, which was significantly lower than the pre-specified goal of 3 breaths/min. The MAE was low in both healthy participants (0.70 ± 0.67 breaths/min), and participants with chronic respiratory conditions (0.80 ± 0.60 breaths/min). Conclusions: These results validate the accuracy of our smartphone camera-based techniques to measure HR and RR across a range of pre-defined subgroups.

4.
Methods Mol Biol ; 2475: 133-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35451754

RESUMO

The ability to study the role of specific genes in endothelial cell biology is made possible by our ability to modulate their expression through siRNA or knockout technologies. However, many in vitro protocols, particularly those of a biochemical nature, require large numbers of endothelial cells. These types of analyses are encumbered by the need to repeatedly produce and characterize primary endothelial cell cultures and can be greatly facilitated by the use of immortalized microvascular endothelial cells. However, we have found that the manipulation of gene expression in these cells is not always straight forward. Here we describe how we alter gene expression in polyoma middle T antigen immortalized microvascular endothelial cells isolated from wild-type and genetically modified mice to study the role of cell adhesion molecules in downstream assays.


Assuntos
Células Endoteliais , Fator A de Crescimento do Endotélio Vascular , Animais , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Camundongos , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(17): e2120439119, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35412862

RESUMO

Long-duration spaceflight induces changes to the brain and cerebrospinal fluid compartments and visual acuity problems known as spaceflight-associated neuro-ocular syndrome (SANS). The clinical relevance of these changes and whether they equally affect crews of different space agencies remain unknown. We used MRI to analyze the alterations occurring in the perivascular spaces (PVS) in NASA and European Space Agency astronauts and Roscosmos cosmonauts after a 6-mo spaceflight on the International Space Station (ISS). We found increased volume of basal ganglia PVS and white matter PVS (WM-PVS) after spaceflight, which was more prominent in the NASA crew than the Roscosmos crew. Moreover, both crews demonstrated a similar degree of lateral ventricle enlargement and decreased subarachnoid space at the vertex, which was correlated with WM-PVS enlargement. As all crews experienced the same environment aboard the ISS, the differences in WM-PVS enlargement may have been due to, among other factors, differences in the use of countermeasures and high-resistive exercise regimes, which can influence brain fluid redistribution. Moreover, NASA astronauts who developed SANS had greater pre- and postflight WM-PVS volumes than those unaffected. These results provide evidence for a potential link between WM-PVS fluid and SANS.


Assuntos
Astronautas , Líquido Cefalorraquidiano , Sistema Glinfático , Voo Espacial , Transtornos da Visão , Líquido Cefalorraquidiano/diagnóstico por imagem , Sistema Glinfático/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Transtornos da Visão/líquido cefalorraquidiano , Transtornos da Visão/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
6.
Cancer Res Commun ; 2(12): 1626-1640, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36970722

RESUMO

Neuropilin (NRP) expression is highly correlated with poor outcome in multiple cancer subtypes. As known coreceptors for VEGFRs, core drivers of angiogenesis, past investigations have alluded to their functional roles in facilitating tumorigenesis by promoting invasive vessel growth. Despite this, it remains unclear as to whether NRP1 and NRP2 act in a synergistic manner to enhance pathologic angiogenesis. Here we demonstrate, using NRP1 ECKO , NRP2 ECKO , and NRP1/NRP2 ECKO mouse models, that maximum inhibition of primary tumor development and angiogenesis is achieved when both endothelial NRP1 and NRP2 are targeted simultaneously. Metastasis and secondary site angiogenesis were also significantly inhibited in NRP1/NRP2 ECKO animals. Mechanistic studies revealed that codepleting NRP1 and NRP2 in mouse-microvascular endothelial cells stimulates rapid shuttling of VEGFR-2 to Rab7+ endosomes for proteosomal degradation. Our results highlight the importance of targeting both NRP1 and NRP2 to modulate tumor angiogenesis. Significance: The findings presented in this study demonstrate that tumor angiogenesis and growth can be arrested completely by cotargeting endothelial NRP1 and NRP2. We provide new insight into the mechanisms of action regulating NRP-dependent tumor angiogenesis and signpost a novel approach to halt tumor progression.


Assuntos
Neoplasias , Neuropilina-1 , Animais , Camundongos , Neuropilina-1/genética , Neuropilina-2/genética , Células Endoteliais/metabolismo , Neovascularização Patológica/genética , Neoplasias/genética
7.
JAMA Netw Open ; 4(10): e2131465, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34705011

RESUMO

Importance: Spaceflight-associated neuro-ocular syndrome (SANS) occurs in 40% to 60% of National Aeronautics and Space Administration (NASA) International Space Station (ISS) astronauts who present postflight with ophthalmological findings and elevated intracranial pressure. The etiology of SANS is unknown; it is hypothesized that venous outflow congestion from the head and neck occurs because of microgravity, which is supported by the finding of internal jugular vein stagnant flow and thrombosis in some astronauts, but the impact on intracranial dural venous sinus structures remains unknown. Objectives: To clarify the potential risk of retrograde extension of clot intracranially among astronauts with internal jugular venous thrombosis by evaluating intracranial venous structures following spaceflight and to assess for any association between intracranial venous congestion and SANS. Design, Setting, and Participants: This retrospective cohort study of all NASA astronauts who had undergone magnetic resonance (MR) venography at the time of the study included quantitative and qualitative assessments of the intracranial venous system on preflight and postflight MR venograms. Data were collected a mean (SD) of 525.8 (187.5) days before spaceflight and 2.0 (1.5) days after return to Earth. A semiautomated segmentation of the venogram images was used, which was then compared with a neuroradiologist's assessment. Exposures: A mean (SD) 184.3 (66.0) days of ISS spaceflight missions. Main Outcomes and Measures: Dural venous sinus volumes before and after spaceflight. Results: A total of 12 astronauts (2 [16.67%] women; 10 [83.33%] men), with a mean (SD) age of 47.8 (5.8) years, were included. Overall, 4 astronauts (33.33%) met the diagnostic criteria for SANS. No dural venous sinus thrombosis was detected for any astronaut. Astronauts with SANS had significantly greater median (range) preflight to postflight increases in volume vs astronauts without SANS for all 3 venous sinus structures: superior sagittal sinus (13.40% [8.70% to 17.47%] vs -2.66% [-15.84% to 5.31%,]; P = .004), right transverse/sigmoid sinus (17.15% [7.63% to 30.08%] vs 0.77% [-14.98% to 15.12%]; P = .02), and left transverse/sigmoid sinus (9.40% [5.20% to 15.50%] vs -1.40% [-14.20% to 12.50%]; P = .03). There was a positive correlation between the neuroradiologist's evaluation and the semiautomated method for the superior sagittal sinus (rpb = 0.64; P = .02) and the right transverse/sigmoid sinus (rpb = 0.58; P = .050). Conclusions and Relevance: These findings, in conjunction with the growing body of evidence of abnormal blood flow dynamics during spaceflight, suggest an association between intracranial venous congestion and SANS. Thus, there is an implication that individuals with increased venous sinus compliance may be at increased risk of developing SANS. These findings should be confirmed in a larger astronaut population and may contribute to understanding disorders of intracranial venous outflow on Earth.


Assuntos
Astronautas , Trombose dos Seios Intracranianos , Voo Espacial , Síndrome , Transtornos da Visão , Adulto , Estudos de Coortes , Feminino , Humanos , Hipertensão Intracraniana , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/epidemiologia , Transtornos da Visão/diagnóstico por imagem , Transtornos da Visão/epidemiologia
8.
Elife ; 102021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34286695

RESUMO

ParABS partition systems, comprising the centromere-like DNA sequence parS, the parS-binding ParB-CTPase, and the nucleoid-binding ParA-ATPase, ensure faithful segregation of bacterial chromosomes and low-copy-number plasmids. F-plasmid partition complexes containing ParBF and parSF move by generating and following a local concentration gradient of nucleoid-bound ParAF. However, the process through which ParBF activates ParAF-ATPase has not been defined. We studied CTP- and parSF-modulated ParAF-ParBF complex assembly, in which DNA-bound ParAF-ATP dimers are activated for ATP hydrolysis by interacting with two ParBF N-terminal domains. CTP or parSF enhances the ATPase rate without significantly accelerating ParAF-ParBF complex assembly. Together, parSF and CTP accelerate ParAF-ParBF assembly without further significant increase in ATPase rate. Magnetic-tweezers experiments showed that CTP promotes multiple ParBF loading onto parSF-containing DNA, generating condensed partition complex-like assemblies. We propose that ParBF in the partition complex adopts a conformation that enhances ParBF-ParBF and ParAF-ParBF interactions promoting efficient partitioning.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Citidina Trifosfato/metabolismo , Proteínas de Bactérias/genética , Sequência de Bases , Centrômero/metabolismo , Cromossomos Bacterianos , Citidina Trifosfato/genética , DNA Primase , DNA Bacteriano , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Plasmídeos , Ligação Proteica , Pirofosfatases
9.
FASEB J ; 35(8): e21679, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34314542

RESUMO

The ability to form a variety of cell-matrix connections is crucial for angiogenesis to take place. Without stable anchorage to the extracellular matrix (ECM), endothelial cells (ECs) are unable to sense, integrate and disseminate growth factor stimulated responses that drive growth of a vascular bed. Neuropilin-2 (NRP2) is a widely expressed membrane-bound multifunctional non-tyrosine kinase receptor, which has previously been implicated in influencing cell adhesion and migration by interacting with α5-integrin and regulating adhesion turnover. α5-integrin, and its ECM ligand fibronectin (FN) are both known to be upregulated during the formation of neo-vasculature. Despite being descriptively annotated as a candidate biomarker for aggressive cancer phenotypes, the EC-specific roles for NRP2 during developmental and pathological angiogenesis remain unexplored. The data reported here support a model whereby NRP2 actively promotes EC adhesion and migration by regulating dynamic cytoskeletal remodeling and by stimulating Rab11-dependent recycling of α5-integrin-p-FAK complexes to newly assembling adhesion sites. Furthermore, temporal depletion of EC-NRP2 in vivo impairs primary tumor growth by disrupting vessel formation. We also demonstrate that EC-NRP2 is required for normal postnatal retinal vascular development, specifically by regulating cell-matrix adhesion. Upon loss of endothelial NRP2, vascular outgrowth from the optic nerve during superficial plexus formation is disrupted, likely due to reduced FAK phosphorylation within sprouting tip cells.


Assuntos
Actinas/metabolismo , Células Endoteliais , Integrina alfa5/metabolismo , Pulmão/irrigação sanguínea , Neovascularização Patológica/metabolismo , Neuropilina-2/fisiologia , Animais , Adesão Celular , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Matriz Extracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Pancreas ; 50(3): 251-279, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33835956

RESUMO

ABSTRACT: Despite considerable research efforts, pancreatic cancer is associated with a dire prognosis and a 5-year survival rate of only 10%. Early symptoms of the disease are mostly nonspecific. The premise of improved survival through early detection is that more individuals will benefit from potentially curative treatment. Artificial intelligence (AI) methodology has emerged as a successful tool for risk stratification and identification in general health care. In response to the maturity of AI, Kenner Family Research Fund conducted the 2020 AI and Early Detection of Pancreatic Cancer Virtual Summit (www.pdac-virtualsummit.org) in conjunction with the American Pancreatic Association, with a focus on the potential of AI to advance early detection efforts in this disease. This comprehensive presummit article was prepared based on information provided by each of the interdisciplinary participants on one of the 5 following topics: Progress, Problems, and Prospects for Early Detection; AI and Machine Learning; AI and Pancreatic Cancer-Current Efforts; Collaborative Opportunities; and Moving Forward-Reflections from Government, Industry, and Advocacy. The outcome from the robust Summit conversations, to be presented in a future white paper, indicate that significant progress must be the result of strategic collaboration among investigators and institutions from multidisciplinary backgrounds, supported by committed funders.


Assuntos
Inteligência Artificial , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Detecção Precoce de Câncer/métodos , Genômica/métodos , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/terapia , Humanos , Comunicação Interdisciplinar , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Prognóstico , Análise de Sobrevida
11.
Hum Brain Mapp ; 42(8): 2490-2507, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33605514

RESUMO

Multicompartment diffusion magnetic resonance imaging (MRI) approaches are increasingly being applied to estimate intra-axonal and extra-axonal diffusion characteristics in the human brain. Fiber ball imaging (FBI) and its extension fiber ball white matter modeling (FBWM) are such recently described multicompartment approaches. However, these particular approaches have yet to be applied in clinical cohorts. The modeling of several diffusion parameters with interpretable biological meaning may offer the development of new, noninvasive biomarkers of pharmacoresistance in epilepsy. In the present study, we used FBI and FBWM to evaluate intra-axonal and extra-axonal diffusion properties of white matter tracts in patients with longstanding focal epilepsy. FBI/FBWM diffusion parameters were calculated along the length of 50 white matter tract bundles and statistically compared between patients with refractory epilepsy, nonrefractory epilepsy and controls. We report that patients with chronic epilepsy had a widespread distribution of extra-axonal diffusivity relative to controls, particularly in circumscribed regions along white matter tracts projecting to cerebral cortex from thalamic, striatal, brainstem, and peduncular regions. Patients with refractory epilepsy had significantly greater markers of extra-axonal diffusivity compared to those with nonrefractory epilepsy. The extra-axonal diffusivity alterations in patients with epilepsy observed in the present study could be markers of neuroinflammatory processes or a reflection of reduced axonal density, both of which have been histologically demonstrated in focal epilepsy. FBI is a clinically feasible MRI approach that provides the basis for more interpretive conclusions about the microstructural environment of the brain and may represent a unique biomarker of pharmacoresistance in epilepsy.


Assuntos
Imagem de Tensor de Difusão/métodos , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsias Parciais/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Biomarcadores , Epilepsia Resistente a Medicamentos/patologia , Epilepsias Parciais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Substância Branca/patologia
12.
Neuroradiology ; 63(8): 1271-1281, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33587162

RESUMO

PURPOSE: Following prolonged stays on the International Space Station (ISS), some astronauts exhibit visual acuity changes, ophthalmological findings, and mildly elevated intracranial pressures as part of a novel process called spaceflight-associated neuro-ocular syndrome (SANS). To determine the pathophysiology of SANS, NASA conducted a multi-investigator study in which 11 healthy participants underwent head-down tilt bed rest, mimicking microgravity-induced cephalad fluid shifts, combined with elevated ambient CO2 levels similar to those on the ISS (HDT+CO2). As part of that study, we examined the effects of HDT+CO2 on cerebral perfusion. METHODS: Using arterial spin labeling, we compared cerebral perfusion before, during, and after HDT+CO2 in participants who developed SANS (n = 5) with those who did not (n = 6). RESULTS: All participants demonstrated a decrease in perfusion during HDT+CO2 (mean decrease of 25.1% at HDT7 and 16.2% at HDT29); however, the timing and degree of change varied between the groups. At day 7 of HDT+CO2, the SANS group experienced a greater reduction in perfusion than the non-SANS group (p =.05, 95% CI:-0.19 to 16.11, d=.94, large effect). Conversely, by day 29 of HDT+CO2, the SANS group had significantly higher perfusion (approaching their baseline) than the non-SANS group (p = .04, 95% CI:0.33 to 13.07, d=1.01, large effect). CONCLUSION: Compared with baseline and recovery, HDT+CO2 resulted in reduced cerebral perfusion which varied based on SANS status. Further studies are needed to unravel the relative role of HDT vs hypercapnia, to determine if these perfusion changes are clinically relevant, and whether perfusion changes contribute to the development of SANS during spaceflight.


Assuntos
Decúbito Inclinado com Rebaixamento da Cabeça , Voo Espacial , Repouso em Cama , Circulação Cerebrovascular , Humanos , Hipercapnia , Perfusão
13.
BMJ Open ; 10(8): e039299, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32784263

RESUMO

INTRODUCTION: A key contributor to underimmunisation is parental refusal or delay of vaccines due to vaccine concerns. Many clinicians lack confidence in communicating with vaccine-hesitant parents (VHP) and perceive that their discussions will do little to change parents' minds. Improving clinician communication with VHPs is critical to increasing childhood vaccine uptake. METHODS AND ANALYSIS: We describe the protocol for a cluster randomised controlled trial to test the impact of a novel, multifaceted clinician vaccine communication strategy on child immunisation status. The trial will be conducted in 24 primary care practices in two US states (Washington and Colorado). The strategy is called Presumptively Initiating Vaccines and Optimizing Talk with Motivational Interviewing (PIVOT with MI), and involves clinicians initiating the vaccine conversation with all parents of young children using the presumptive format, and among those parents who resist vaccines, pivoting to using MI. Our primary outcome is the immunisation status of children of VHPs at 19 months, 0 day of age expressed as the percentage of days underimmunised from birth to 19 months for 22 doses of eight vaccines recommended during this interval. Secondary outcomes include clinician experience communicating with VHPs, parent visit experience and clinician adherence to the PIVOT with MI communication strategy. ETHICS AND DISSEMINATION: This study is approved by the following institutional review boards: Colorado Multiple Institutional Review Board, Washington State Institutional Review Board and Swedish Health Services Institutional Review Board. Results will be disseminated through peer-reviewed manuscripts and conference presentations. TRIAL REGISTRATION NUMBER: NCT03885232.


Assuntos
Entrevista Motivacional , Vacinas , Criança , Pré-Escolar , Colorado , Comunicação , Humanos , Lactente , Pais , Ensaios Clínicos Controlados Aleatórios como Assunto , Vacinação , Washington
14.
Nat Biomed Eng ; 4(1): 52-68, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31937944

RESUMO

A small percentage of the short interfering RNA (siRNA) delivered via passive lipid nanoparticles and other delivery vehicles reaches the cytoplasm of cells. The high doses of siRNA and delivery vehicle that are thus required to achieve therapeutic outcomes can lead to toxicity. Here, we show that the integration of siRNA sequences into a Dicer-independent RNA stem-loop based on pre-miR-451 microRNA-which is highly enriched in small extracellular vesicles secreted by many cell types-reduces the expression of the genes targeted by the siRNA in the liver, intestine and kidney glomeruli of mice at siRNA doses that are at least tenfold lower than the siRNA doses typically delivered via lipid nanoparticles. Small extracellular vesicles that efficiently package siRNA can significantly reduce its therapeutic dose.


Assuntos
Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , MicroRNAs/química , Neurônios Motores/efeitos dos fármacos , Nanopartículas/administração & dosagem , Interferência de RNA , RNA Interferente Pequeno/química
15.
Pediatr Emerg Care ; 36(2): e43-e49, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29040244

RESUMO

OBJECTIVE: This study had 2 objectives. First, to determine the behavior of physicians evaluating premobile infants with bruises. Second, and most importantly, to learn whether infants with unexplained bruising who had been initially evaluated by primary care and emergency department (ED) physicians are as likely to have their bruises attributed to child abuse as those children evaluated by child abuse physicians. METHODS: Primary care, ED, and child abuse pediatricians (CAPs) in King County, Washington, San Mateo, Calif, Albuquerque, NM, La Crosse, Wis, and Torrance, Calif prospectively identified and studied infants younger than 6 months with less than 6 bruises, which were judged by the evaluating clinician to be explained or unexplained after their initial clinical examination. RESULTS: Between March 1, 2010, and March 1, 2017, 63 infants with initially explained and 46 infants with initially unexplained bruises were identified. Infants with unexplained bruises had complete coagulation and abuse evaluations less frequently if they were initially identified by primary care pediatricians or ED providers than by CAPs. After imaging, laboratory, and follow-up, 54.2% (26) of the infants with initially unexplained bruises, including 2 who had been initially diagnosed with accidental injuries, were diagnosed as abused. Three (6.2%) infants had accidental bruising, 6 (12.4%) abuse mimics, 1 (2.5%) self-injury, 1 (2.5%) medical injury, and 11 (22.9%) remained of unknown causation. None had causal coagulation disorders. A total of 65.4% of the 26 abused infants had occult injuries detected by their imaging and laboratory evaluations. Six (23.1%) abused infants were not diagnosed until after they sustained subsequent injuries. Three (11.5%) were recognized abused by police investigation alone. Thirty-eight percent of the abused, bruised infants had a single bruise. Clinicians' estimates of abuse likelihood based on their initial clinical evaluation were inaccurate. Primary care, ED, and child abuse physicians identified abused infants at similar rates. CONCLUSIONS: More than half of premobile infants with initially unexplained bruises were found to be abused. Abuse was as likely for infants identified by primary care and ED providers as for those identified by CAPs. Currently, physicians often do not obtain full abuse evaluations in premobile infants with unexplained bruising. Their initial clinical judgment about abuse likelihood was inadequate. Bruised infants often have clinically occult abusive injuries or will sustain subsequent serious abuse. Bruised infants should have full abuse evaluations and referral for Protective Services and police assessments.


Assuntos
Maus-Tratos Infantis/diagnóstico , Contusões/diagnóstico , Contusões/etiologia , Exame Físico , Maus-Tratos Infantis/estatística & dados numéricos , Contusões/epidemiologia , Serviço Hospitalar de Emergência , Pessoal de Saúde/psicologia , Humanos , Lactente , Recém-Nascido , Funções Verossimilhança , Movimento , Atenção Primária à Saúde , Estudos Prospectivos , Estados Unidos
16.
Sci Rep ; 9(1): 16679, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723182

RESUMO

GapR is a nucleoid-associated protein required for the cell cycle of Caulobacter cresentus. We have determined new crystal structures of GapR to high resolution. As in a recently published structure, a GapR monomer folds into one long N-terminal α helix and two shorter α helices, and assembles into a tetrameric ring with a closed, positively charged, central channel. In contrast to the conclusions drawn from the published structures, we observe that the central channel of the tetramer presented here could freely accommodate B-DNA. Mutation of six conserved lysine residues lining the cavity and electrophoretic mobility gel shift experiments confirmed their role in DNA binding and the channel as the site of DNA binding. Although present in our crystals, DNA could not be observed in the electron density maps, suggesting that DNA binding is non-specific, which could be important for tetramer-ring translocation along the chromosome. In conjunction with previous GapR structures we propose a model for DNA binding and translocation that explains key published observations on GapR and its biological functions.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Caulobacter crescentus/metabolismo , DNA de Forma B/metabolismo , DNA Bacteriano/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , DNA de Forma B/química , DNA Bacteriano/química , Modelos Moleculares
17.
Pediatrics ; 144(5)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31597690

RESUMO

OBJECTIVE: To evaluate the effect of vaccine hesitancy screening on childhood vaccine uptake. METHODS: We conducted a cluster randomized controlled trial in pediatric primary care clinics in Washington state. Vaccine-hesitant parents (VHPs) with a healthy newborn receiving health supervision at participating clinics were eligible. VHPs were identified by using a 4-item version of the validated Parent Attitudes About Childhood Vaccines Survey (PACV). Before their child's 2- and 6-month health supervision visits, VHPs at intervention clinics completed the 15-item PACV embedded in a survey containing placebo items. Intervention providers received a summary of parents' 15-item PACV responses and interpretation of their PACV score; discretion was given to providers regarding how they acted on this information. VHPs at control clinics completed only the placebo survey items, and their child's provider received a summary of their responses; control providers remained blinded to parent VHP status. Our outcome was child immunization status at 8 months of age expressed as percent of days underimmunized. We compared outcomes in control and intervention participants using t test and linear mixed-effects regression. RESULTS: We enrolled 24 clinics (12 in each arm) and 156 parents (65 in the intervention arm). Parent characteristics were similar across arms except more intervention (versus control) parents had a first-born child (60.9% vs 44%; P = .04). No significant difference in outcome was detected between arms (25.2% [95% confidence interval: 16.0% to 34.5%] vs 19.1% [95% confidence interval: 12.0% to 26.3%] mean days underimmunized in the intervention and control arms, respectively). CONCLUSION: Vaccine hesitancy screening was not significantly associated with days underimmunized.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Recusa de Vacinação/psicologia , Vacinação/psicologia , Adulto , Análise por Conglomerados , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Vacinas/administração & dosagem
18.
Microbiologyopen ; 8(11): e915, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31496120

RESUMO

Bacterial colonization of the urogenital tract is limited by innate defenses, including the production of antimicrobial peptides (AMPs). Uropathogenic Escherichia coli (UPEC) resist AMP-killing to cause a range of urinary tract infections (UTIs) including asymptomatic bacteriuria, cystitis, pyelonephritis, and sepsis. UPEC strains have high genomic diversity and encode numerous virulence factors that differentiate them from non-UTI-causing strains, including ompT. As OmpT homologs cleave and inactivate AMPs, we hypothesized that UPEC strains from patients with symptomatic UTIs have high OmpT protease activity. Therefore, we measured OmpT activity in 58 clinical E. coli isolates. While heterogeneous OmpT activities were observed, OmpT activity was significantly greater in UPEC strains isolated from patients with symptomatic infections. Unexpectedly, UPEC strains exhibiting the greatest protease activities harbored an additional ompT-like gene called arlC (ompTp). The presence of two OmpT-like proteases in some UPEC isolates led us to compare the substrate specificities of OmpT-like proteases found in E. coli. While all three cleaved AMPs, cleavage efficiency varied on the basis of AMP size and secondary structure. Our findings suggest the presence of ArlC and OmpT in the same UPEC isolate may confer a fitness advantage by expanding the range of target substrates.


Assuntos
Proteínas da Membrana Bacteriana Externa/análise , Proteínas de Escherichia coli/análise , Peptídeo Hidrolases/análise , Escherichia coli Uropatogênica/enzimologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Humanos , Hidrólise , Peptídeo Hidrolases/química , Peptídeo Hidrolases/genética , Reação em Cadeia da Polimerase , Especificidade por Substrato , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/isolamento & purificação , Fatores de Virulência/análise , Fatores de Virulência/química , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
19.
JAMA Netw Open ; 2(5): e193581, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31074815

RESUMO

Importance: Health risk behaviors are a leading cause of morbidity during adolescence. Screening and counseling for health risk behaviors are recommended but infrequently performed. Objective: To test the effect of an electronic screening and feedback tool on clinician counseling and adolescent-reported health risk behaviors. Design, Setting, and Participants: A randomized clinical trial compared electronic screening and feedback on an intention-to-treat basis with usual care among 300 youths 13 to 18 years of age at 5 pediatric clinics in the Pacific Northwest. Outcomes were assessed via electronic survey at 1 day and 3 months after the initial visit. Study data collection occurred from March 13, 2015, to November 29, 2016, and statistical analysis was conducted between February 6, 2017, and June 20, 2018. Interventions: Youths in the intervention group (n = 147) received electronic screening and personalized feedback with clinician clinical decision support. Youths in the control group (n = 153) received standard screening and counseling as provided by their clinic. Main Outcomes and Measures: Youths' report of receipt of counseling during the visit and risk behaviors at 3 months. Results: In the final study sample of 300 youths (intervention group, 75 girls and 72 boys; mean [SD] age, 14.5 [1.4 years]; and control group, 80 girls and 73 boys; mean [SD] age, 14.5 [1.4] years), 234 (78.0%) were aged 13 to 15 years. After adjusting for age, sex, and random effect of clinic, youths in the intervention group were more likely to receive counseling for each of their reported risk behaviors than were youths in the control group (adjusted rate ratio, 1.32; 95% CI, 1.07-1.63). Youths in the intervention group had a significantly greater reduction (ß = -0.48; 95% CI, -0.89 to -0.02; P = .02) in their risk behavior scores at 3 months when compared with youths in the control group. Conclusions and Relevance: Electronic screening of health risk behavior with clinical decision support and motivational feedback to teens can improve care delivery and outcomes. Trial Registration: ClinicalTrials.gov identifier: NCT02360410.


Assuntos
Comportamento do Adolescente/psicologia , Feedback Formativo , Comportamentos de Risco à Saúde , Programas de Rastreamento/métodos , Adolescente , Aconselhamento , Técnicas de Apoio para a Decisão , Feminino , Humanos , Masculino , Atenção Primária à Saúde/métodos , Autorrelato , Resultado do Tratamento
20.
Pediatrics ; 142(4)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30249625
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