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1.
J Immunol ; 212(10): 1579-1588, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38557795

RESUMO

Abs are vital to human immune responses and are composed of genetically variable H and L chains. These structures are initially expressed as BCRs. BCR diversity is shaped through somatic hypermutation and selection during immune responses. This evolutionary process produces B cell clones, cells that descend from a common ancestor but differ by mutations. Phylogenetic trees inferred from BCR sequences can reconstruct the history of mutations within a clone. Until recently, BCR sequencing technologies separated H and L chains, but advancements in single-cell sequencing now pair H and L chains from individual cells. However, it is unclear how these separate genes should be combined to infer B cell phylogenies. In this study, we investigated strategies for using paired H and L chain sequences to build phylogenetic trees. We found that incorporating L chains significantly improved tree accuracy and reproducibility across all methods tested. This improvement was greater than the difference between tree-building methods and persisted even when mixing bulk and single-cell sequencing data. However, we also found that many phylogenetic methods estimated significantly biased branch lengths when some L chains were missing, such as when mixing single-cell and bulk BCR data. This bias was eliminated using maximum likelihood methods with separate branch lengths for H and L chain gene partitions. Thus, we recommend using maximum likelihood methods with separate H and L chain partitions, especially when mixing data types. We implemented these methods in the R package Dowser: https://dowser.readthedocs.io.


Assuntos
Linfócitos B , Filogenia , Receptores de Antígenos de Linfócitos B , Humanos , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Linfócitos B/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/imunologia , Análise de Célula Única/métodos , Mutação
2.
BMC Med Res Methodol ; 24(1): 66, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481139

RESUMO

BACKGROUND: Treatment variation from observational data has been used to estimate patient-specific treatment effects. Causal Forest Algorithms (CFAs) developed for this task have unknown properties when treatment effect heterogeneity from unmeasured patient factors influences treatment choice - essential heterogeneity. METHODS: We simulated eleven populations with identical treatment effect distributions based on patient factors. The populations varied in the extent that treatment effect heterogeneity influenced treatment choice. We used the generalized random forest application (CFA-GRF) to estimate patient-specific treatment effects for each population. Average differences between true and estimated effects for patient subsets were evaluated. RESULTS: CFA-GRF performed well across the population when treatment effect heterogeneity did not influence treatment choice. Under essential heterogeneity, however, CFA-GRF yielded treatment effect estimates that reflected true treatment effects only for treated patients and were on average greater than true treatment effects for untreated patients. CONCLUSIONS: Patient-specific estimates produced by CFAs are sensitive to why patients in real-world practice make different treatment choices. Researchers using CFAs should develop conceptual frameworks of treatment choice prior to estimation to guide estimate interpretation ex post.


Assuntos
Algoritmos , Pacientes , Humanos , Heterogeneidade da Eficácia do Tratamento , Causalidade , Seleção de Pacientes , Simulação por Computador
3.
Prehosp Emerg Care ; : 1-12, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661320

RESUMO

INTRODUCTION: Early administration of antibiotics for open fractures reduces serious bone and soft tissue infections. The effectiveness of antibiotics in reducing these infections is time-dependent, with various surgical associations recommending administration within one hour of injury, or within one hour of patient arrival to the emergency department (ED). The extent to which prehospital antibiotic administration in these situations might reduce the time to treatment has not been previously reported. The purpose of this study was to describe current prehospital use of antibiotics for traumatic injury, to assess the safety of prehospital antibiotic administration, and to estimate the potential time-savings associated with antibiotic administration by EMS clinicians. METHODS: This was a retrospective analysis of the 2019 through 2022 ESO Data Collaborative research data set. Included subjects were patients that had a linked ICD-10 code indicating an open extremity fracture and who received prehospital antibiotics. Time to antibiotic administration was calculated as the elapsed time from EMS dispatch until antibiotic administration. The minimum potential time saved by EMS antibiotic administration was calculated as the elapsed time from administration until ED arrival. To assess safety, epinephrine and diphenhydramine administration were used as proxies for the adverse events of anaphylaxis and minor allergic reactions. RESULTS: There were 523 patients meeting the inclusion criteria. The median (and interquartile range [IQR]) elapsed time from EMS dispatch until antibiotic administration was 31 (IQR: 24-41) minutes. The median potential time savings associated with prehospital antibiotic administration was 15 (IQR: 8-22) minutes. Notably, 144 (27.5%) of the patients who received prehospital antibiotics had total prehospital times exceeding one hour. None of the patients who received antibiotics also received epinephrine for presumed anaphylaxis. CONCLUSIONS: EMS clinicians were able to safely administer antibiotics to patients with open fractures a median of 15 minutes before arrival at the hospital, and 99 percent of the patients receiving antibiotics had them administered within one hour of EMS dispatch. EMS administration of antibiotics may be a safe way to increase compliance with recommendations for early antibiotic administration for open fractures.

4.
PLoS Biol ; 18(8): e3000869, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32822393

RESUMO

Genomic epidemiology can provide a unique, real-time understanding of SARS-CoV-2 transmission patterns. Yet the potential for genomic analyses to guide local policy and community-based behavioral decisions is limited because they are often oriented towards specially trained scientists and conducted on a national or global scale. Here, we propose a new paradigm: Phylogenetic analyses performed on a local level (municipal, county, or state), with results communicated in a clear, timely, and actionable manner to strengthen public health responses. We believe that presenting results rapidly, and tailored to a non-expert audience, can serve as a template for effective public health response to COVID-19 and other emerging viral diseases.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Disseminação de Informação , Pneumonia Viral/epidemiologia , Saúde Pública , COVID-19 , Genômica , Humanos , Pandemias , Filogenia , SARS-CoV-2
5.
Mar Drugs ; 21(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36662226

RESUMO

Sponges are the richest source of bioactive organic small molecules, referred to as natural products, in the marine environment. It is well established that laboratory culturing-resistant symbiotic bacteria residing within the eukaryotic sponge host matrix often synthesize the natural products that are detected in the sponge tissue extracts. However, the contributions of the culturing-amenable commensal bacteria that are also associated with the sponge host to the overall metabolome of the sponge holobiont are not well defined. In this study, we cultured a large library of bacteria from three marine sponges commonly found in the Florida Keys. Metabolomes of isolated bacterial strains and that of the sponge holobiont were compared using mass spectrometry to reveal minimal metabolomic overlap between commensal bacteria and the sponge hosts. We also find that the phylogenetic overlap between cultured commensal bacteria and that of the sponge microbiome is minimal. Despite these observations, the commensal bacteria were found to be a rich resource for novel natural product discovery. Mass spectrometry-based metabolomics provided structural insights into these cryptic natural products. Pedagogic innovation in the form of laboratory curricula development is described which provided undergraduate students with hands-on instruction in microbiology and natural product discovery using metabolomic data mining strategies.


Assuntos
Produtos Biológicos , Poríferos , Animais , Humanos , Filogenia , Georgia , Poríferos/microbiologia , Bactérias , Metabolômica , Estudantes , Produtos Biológicos/química
6.
Eur J Clin Microbiol Infect Dis ; 41(11): 1295-1304, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36114431

RESUMO

To establish a biological profile and disease aetiologies for one of four burials recovered during a Time Team dig at the St. Mary Magdalen leprosarium, Winchester, UK in AD 2000. Osteological techniques were applied to estimate age at death, biological sex, stature and pathology. Visual assessment of the material was supplemented by radiographic examination. Evidence for leprosy DNA was sought using ancient DNA (aDNA) analysis. The remains are those of a male individual excavated from a west-east aligned grave. The skeleton shows signs of two pathologies. Remodelling of the rhino-maxillary area and degenerative changes to small bones of the feet and reactive bone on the distal lower limbs suggest a multibacillary form of leprosy, whereas the right tibia and fibula show the presence of a primary neoplasm identified as an osteosarcoma. The aDNA study confirmed presence of Mycobacterium leprae in several skeletal elements, and the strain was genotyped to the 3I lineage, one of two main SNP types present in mediaeval Britain and ancestral to extant strains in America. This is a rare documentation of leprosy in association with a primary neoplasm.


Assuntos
Hanseníase Virchowiana , Hanseníase , Osteossarcoma , Osso e Ossos , DNA Antigo , Humanos , Hanseníase/diagnóstico , Hanseníase Virchowiana/microbiologia , Masculino , Mycobacterium leprae/genética , Osteossarcoma/genética , Reino Unido
7.
BMC Med Res Methodol ; 22(1): 190, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35818028

RESUMO

BACKGROUND: Comparative effectiveness research (CER) using observational databases has been suggested to obtain personalized evidence of treatment effectiveness. Inferential difficulties remain using traditional CER approaches especially related to designating patients to reference classes a priori. A novel Instrumental Variable Causal Forest Algorithm (IV-CFA) has the potential to provide personalized evidence using observational data without designating reference classes a priori, but the consistency of the evidence when varying key algorithm parameters remains unclear. We investigated the consistency of IV-CFA estimates through application to a database of Medicare beneficiaries with proximal humerus fractures (PHFs) that previously revealed heterogeneity in the effects of early surgery using instrumental variable estimators. METHODS: IV-CFA was used to estimate patient-specific early surgery effects on both beneficial and detrimental outcomes using different combinations of algorithm parameters and estimate variation was assessed for a population of 72,751 fee-for-service Medicare beneficiaries with PHFs in 2011. Classification and regression trees (CART) were applied to these estimates to create ex-post reference classes and the consistency of these classes were assessed. Two-stage least squares (2SLS) estimators were applied to representative ex-post reference classes to scrutinize the estimates relative to known 2SLS properties. RESULTS: IV-CFA uncovered substantial early surgery effect heterogeneity across PHF patients, but estimates for individual patients varied with algorithm parameters. CART applied to these estimates revealed ex-post reference classes consistent across algorithm parameters. 2SLS estimates showed that ex-post reference classes containing older, frailer patients with more comorbidities, and lower utilizers of healthcare were less likely to benefit and more likely to have detriments from higher rates of early surgery. CONCLUSIONS: IV-CFA provides an illuminating method to uncover ex-post reference classes of patients based on treatment effects using observational data with a strong instrumental variable. Interpretation of treatment effect estimates within each ex-post reference class using traditional CER methods remains conditional on the extent of measured information in the data.


Assuntos
Medicare , Fraturas do Ombro , Idoso , Algoritmos , Causalidade , Florestas , Humanos , Estados Unidos
8.
Health Promot Pract ; 23(1_suppl): 21S-33S, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36374599

RESUMO

Practitioners in health departments, university extension programs, and nonprofit organizations working in public health face varied challenges to publishing in the peer-reviewed literature. These practitioners may lack time, support, skills, and efficacy needed for manuscript submission, which keeps them from sharing their wisdom and experience-based evidence. This exclusion can contribute to literature gaps, a failure of evidence-based practice to inform future research, reduced ability to educate partners, and delays in advancing public health practice. Our article describes the writing workshops offered to Division of Nutrition, Physical Activity, and Obesity (DNPAO), Centers for Disease Control and Prevention (CDC) funded programs in 2021. This project consisted of three 60-minute introductory writing webinars open to all recipients, followed by a Writing for Publications workshop, an 8- to 9-week virtual learning/writing intensive for selected writing team applicants. The Society for Public Health Education staff, consultants, and CDC/DNPAO staff developed, refined, and presented the curriculum. The workshop for public health practitioner writing teams was offered to two cohorts and included extensive coaching and focused on potential submission to a Health Promotion Practice supplement, "Reducing Chronic Disease through Physical Activity and Nutrition: Public Health Practice in the Field" (see Supplemental Material), which was supported by CDC/DNPAO. We describe the webinars, the workshop design, modifications, evaluation methods and results.


Assuntos
Currículo , Redação , Humanos , Estados Unidos , Promoção da Saúde , Saúde Pública , Centers for Disease Control and Prevention, U.S.
9.
Ann Oncol ; 32(5): 600-608, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33539945

RESUMO

BACKGROUND: First-line treatment of metastatic pancreatic ductal adenocarcinoma (PDAC) includes nab-paclitaxel/gemcitabine. Ibrutinib, a Bruton's tyrosine kinase inhibitor, exhibits antitumor activity through tumor microenvironment modulation. The safety and efficacy of first-line ibrutinib plus nab-paclitaxel/gemcitabine treatment in patients with PDAC were evaluated. PATIENTS AND METHODS: RESOLVE (NCT02436668) was a phase III, randomized, double-blind, placebo-controlled study. Patients (histologically-confirmed PDAC; stage IV diagnosis ≥6 weeks of randomization; Karnofsky performance score ≥70) were randomized to once-daily oral ibrutinib (560 mg) or placebo plus nab-paclitaxel (125 mg/m2) and gemcitabine (1000 mg/m2). Primary endpoints were overall survival (OS) and investigator-assessed progression-free survival (PFS); overall response rate and safety were assessed. RESULTS: In total, 424 patients were randomized (ibrutinib arm, n = 211; placebo arm, n = 213). Baseline characteristics were balanced across arms. After a median follow-up of 25 months, there was no significant difference in OS between ibrutinib plus nab-paclitaxel/gemcitabine versus placebo plus nab-paclitaxel/gemcitabine (median of 9.7 versus 10.8 months; P = 0.3225). PFS was shorter for ibrutinib plus nab-paclitaxel/gemcitabine compared with placebo plus nab-paclitaxel/gemcitabine (median 5.3 versus 6.0 months; P < 0.0001). Overall response rates were 29% and 42%, respectively (P = 0.0058). Patients in the ibrutinib arm had less time on treatment and received lower cumulative doses for all agents compared with the placebo arm. The most common grade ≥3 adverse events for ibrutinib versus placebo arms included neutropenia (24% versus 35%), peripheral sensory neuropathy (17% versus 8%), and anemia (16% versus 17%). Primary reasons for any treatment discontinuation were disease progression and adverse events. CONCLUSIONS: Ibrutinib plus nab-paclitaxel/gemcitabine did not improve OS or PFS for patients with PDAC. Safety was consistent with known profiles for these agents.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adenina/análogos & derivados , Adenocarcinoma/tratamento farmacológico , Albuminas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/análogos & derivados , Humanos , Paclitaxel/efeitos adversos , Neoplasias Pancreáticas/tratamento farmacológico , Piperidinas , Resultado do Tratamento , Microambiente Tumoral , Gencitabina
10.
J Shoulder Elbow Surg ; 29(7S): S115-S125, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32646593

RESUMO

BACKGROUND: Prescription opioids are standard of care for postoperative pain management after musculoskeletal surgery, but there is no guideline or consensus on best practices. Variability in the intensity of opioids prescribed for postoperative recovery has been documented, but it is unclear whether this variability is clinically motivated or associated with provider practice patterns, or how this variation is associated with patient outcomes. This study described variation in the intensity of opioids prescribed for patients undergoing rotator cuff repair (RCR) and examined associations with provider prescribing patterns and patients' long-term opioid use outcomes. METHODS: Medicare data from 2010 to 2012 were used to identify 16,043 RCRs for patients with new shoulder complaints in 2011. Two measures of perioperative opioid use were created: (1) any opioid fill occurring 3 days before to 7 days after RCR and (2) total morphine milligram equivalents (MMEs) of all opioid fills during that period. Patient outcomes for persistent opioid use after RCR included (1) any opioid fill from 90 to 180 days after RCR and (2) the lack of any 30-day gap in opioid availability during that period. Generalized linear regression models were used to estimate associations between provider characteristics and opioid use for RCR, and between opioid use and outcomes. All models adjusted for patient clinical and demographic characteristics. Separate analyses were done for patients with and without opioid use in the 180 days before RCR. RESULTS: In this sample, 54% of patients undergoing RCR were opioid naive at the time of RCR. Relative to prior users, a greater proportion of opioid naive users had any opioid fill (85.7% vs. 75.4%), but prior users received more MMEs than naive users (565 vs. 451 MMEs). Providers' opioid prescribing for other patients was associated with the intensity of perioperative opioids received for RCR. Total MMEs received for RCR were associated with higher odds of persistent opioid use 90-180 days after RCR. CONCLUSIONS: The intensity of opioids received by patients for postoperative pain appears to be partially determined by the prescribing habits of their providers. Greater intensity of opioids received is, in turn, associated with greater odds of patterns of chronic opioid use after surgery. More comprehensive, patient-centered guidance on opioid prescribing is needed to help surgeons provide optimal postoperative pain management plans, balancing needs for short-term symptom relief and risks for long-term outcomes.


Assuntos
Analgésicos Opioides/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Cirurgiões Ortopédicos/estatística & dados numéricos , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Lesões do Manguito Rotador/cirurgia , Idoso , Analgésicos Opioides/efeitos adversos , Artroplastia/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Humanos , Masculino , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Opioides/etiologia , Dor Pós-Operatória/epidemiologia , Estudos Retrospectivos , Lesões do Manguito Rotador/epidemiologia , Estados Unidos/epidemiologia
11.
Environ Monit Assess ; 192(8): 539, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32705349

RESUMO

Microbial communities occur in almost every habitat. To evaluate the homeostasis disruption of in situ microbiomes, dredged sediments from Guanabara Bay-Brazil (GB) were mixed with sediments from outside of the bay (D) in three different proportions (25%, 50%, and 75%) which we called GBD25, GBD50, and GBD75. Grain size, TOC, and metals-as indicators of complex contamination-dehydrogenase (DHA) and esterase enzymes (EST)-as indicators of microbial community availability-were determined. Microbial community composition was addressed by amplifying the 16S rRNA gene for DGGE analysis and sequencing using MiSeq platform (Illumina).We applied the quality ratio index (QR) to the GB, D, and every GBD mixture to integrate geochemical parameters with our microbiome data. QR indicated high environmental risk for GB and every GBD mixture, and low risk for D. The community shifted from aerobic to anaerobic profile, consistent with the characteristics of GB. Sample D was dominated by JTB255 marine benthic group, related to low impacted areas. Milano-WF1B-44 was the most representative of GB, often found in anaerobic and sulfur enriched environments. In GBD, the denitrifying sulfur-oxidizing bacteria, Sulfurovum, was the most representative, typically found in suboxic or anoxic niches. The canonical correspondence analysis was able to explain 60% of the community composition variation and exhibit the decrease of environmental quality as the contamination increases. Physiological and taxonomic shifts of the microbial assemblage in sediments were inferred by QR, which was suitable to determine sediment risk. The study produced sufficient information to improve the dredging plan and management.


Assuntos
Sedimentos Geológicos , Microbiota , Baías , Brasil , Monitoramento Ambiental , RNA Ribossômico 16S
12.
Glia ; 67(3): 452-466, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30548313

RESUMO

Stem/progenitor cell transplantation delivery of astrocytes is a potentially powerful strategy for spinal cord injury (SCI). Axon extension into SCI lesions that occur spontaneously or in response to experimental manipulations is often observed along endogenous astrocyte "bridges," suggesting that augmenting this response via astrocyte lineage transplantation can enhance axon regrowth. Given the importance of respiratory dysfunction post-SCI, we transplanted glial-restricted precursors (GRPs)-a class of lineage-restricted astrocyte progenitors-into the C2 hemisection model and evaluated effects on diaphragm function and the growth response of descending rostral ventral respiratory group (rVRG) axons that innervate phrenic motor neurons (PhMNs). GRPs survived long term and efficiently differentiated into astrocytes in injured spinal cord. GRPs promoted significant recovery of diaphragm electromyography amplitudes and stimulated robust regeneration of injured rVRG axons. Although rVRG fibers extended across the lesion, no regrowing axons re-entered caudal spinal cord to reinnervate PhMNs, suggesting that this regeneration response-although impressive-was not responsible for recovery. Within ipsilateral C3-5 ventral horn (PhMN location), GRPs induced substantial sprouting of spared fibers originating in contralateral rVRG and 5-HT axons that are important for regulating PhMN excitability; this sprouting was likely involved in functional effects of GRPs. Finally, GRPs reduced the macrophage response (which plays a key role in inducing axon retraction and limiting regrowth) both within the hemisection and at intact caudal spinal cord surrounding PhMNs. These findings demonstrate that astrocyte progenitor transplantation promotes significant plasticity of rVRG-PhMN circuitry and restoration of diaphragm function and suggest that these effects may be in part through immunomodulation.


Assuntos
Axônios/fisiologia , Macrófagos/metabolismo , Neurônios Motores/fisiologia , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/transplante , Recuperação de Função Fisiológica/fisiologia , Respiração , Traumatismos da Medula Espinal/terapia , Animais , Vértebra Cervical Áxis , Feminino , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/fisiopatologia
13.
Neurobiol Dis ; 127: 432-448, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30951849

RESUMO

Alzheimer's disease (AD) genetics implies a causal role for innate immune genes, TREM2 and CD33, products that oppose each other in the downstream Syk tyrosine kinase pathway, activating microglial phagocytosis of amyloid (Aß). We report effects of low (Curc-lo) and high (Curc-hi) doses of curcumin on neuroinflammation in APPsw transgenic mice. Results showed that Curc-lo decreased CD33 and increased TREM2 expression (predicted to decrease AD risk) and also increased TyroBP, which controls a neuroinflammatory gene network implicated in AD as well as phagocytosis markers CD68 and Arg1. Curc-lo coordinately restored tightly correlated relationships between these genes' expression levels, and decreased expression of genes characteristic of toxic pro-inflammatory M1 microglia (CD11b, iNOS, COX-2, IL1ß). In contrast, very high dose curcumin did not show these effects, failed to clear amyloid plaques, and dysregulated gene expression relationships. Curc-lo stimulated microglial migration to and phagocytosis of amyloid plaques both in vivo and in ex vivo assays of sections of human AD brain and of mouse brain. Curcumin also reduced levels of miR-155, a micro-RNA reported to drive a neurodegenerative microglial phenotype. In conditions without amyloid (human microglial cells in vitro, aged wild-type mice), Curc-lo similarly decreased CD33 and increased TREM2. Like curcumin, anti-Aß antibody (also reported to engage the Syk pathway, increase CD68, and decrease amyloid burden in human and mouse brain) increased TREM2 in APPsw mice and decreased amyloid in human AD sections ex vivo. We conclude that curcumin is an immunomodulatory treatment capable of emulating anti-Aß vaccine in stimulating phagocytic clearance of amyloid by reducing CD33 and increasing TREM2 and TyroBP, while restoring neuroinflammatory networks implicated in neurodegenerative diseases.


Assuntos
Doença de Alzheimer/genética , Anti-Inflamatórios não Esteroides/farmacologia , Encéfalo/efeitos dos fármacos , Curcumina/farmacologia , Expressão Gênica/efeitos dos fármacos , Imunidade Inata/genética , Microglia/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Humanos , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Fagocitose/efeitos dos fármacos , Placa Amiloide/genética , Placa Amiloide/metabolismo , Receptores Imunológicos/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo
14.
Opt Express ; 27(14): 19141-19149, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503677

RESUMO

A cavity ringdown system for probing the spatial variation of optical loss across high-reflectivity mirrors is described. This system is employed to examine substrate-transferred crystalline supermirrors and to quantify the effect of manufacturing process imperfections. Excellent agreement is observed between the ringdown-generated spatial measurements and differential interference contrast microscopy images. A 2-mm diameter ringdown scan in the center of a crystalline supermirror reveals highly uniform coating properties with excess loss variations below 1 ppm.

15.
Opt Express ; 27(25): 36731-36740, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873446

RESUMO

Precision interferometry is the leading method for extremely sensitive measurements in gravitational wave astronomy. Thermal noise of dielectric coatings poses a limitation to the sensitivity of these interferometers. To decrease coating thermal noise, new crystalline GaAs/AlGaAs multilayer mirrors have been developed. To date, the surface figure and thickness uniformity of these alternative low-loss coatings has not been investigated. Surface figure errors, for example, cause small angle scattering and thereby limit the sensitivity of an interferometer. Here we measure the surface figure of highly reflective, substrate-transferred, crystalline GaAs/AlGaAs coatings with a custom scanning reflectance system. We exploit the fact that the reflectivity varies with the thickness of the coating. To increase penetration into the coating, we used a 1550 nm laser on a highly reflective coating designed for a center wavelength of 1064 nm. The RMS thickness variation of a two inch optic was measured to be 0.41 ± 0.05 nm. This result is within 10% of the thickness uniformity, of 0.37 nm RMS, achieved with ion-beam sputtered coatings for the aLIGO detector. We additionally measured a lower limit of the laser induced damage threshold of 64 MW/cm 2 for GaAs/AlGaAs coatings at a wavelength of 1064 nm.

16.
Health Econ ; 27(6): 937-955, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29577493

RESUMO

This study used Monte Carlo simulations to examine the ability of the two-stage least squares (2SLS) estimator and two-stage residual inclusion (2SRI) estimators with varying forms of residuals to estimate the local average and population average treatment effect parameters in models with binary outcome, endogenous binary treatment, and single binary instrument. The rarity of the outcome and the treatment was varied across simulation scenarios. Results showed that 2SLS generated consistent estimates of the local average treatment effects (LATE) and biased estimates of the average treatment effects (ATE) across all scenarios. 2SRI approaches, in general, produced biased estimates of both LATE and ATE under all scenarios. 2SRI using generalized residuals minimized the bias in ATE estimates. Use of 2SLS and 2SRI is illustrated in an empirical application estimating the effects of long-term care insurance on a variety of binary health care utilization outcomes among the near-elderly using the Health and Retirement Study.


Assuntos
Simulação por Computador , Modelos Econométricos , Método de Monte Carlo , Idoso , Humanos , Assistência de Longa Duração , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos
17.
Pharmacoepidemiol Drug Saf ; 27(2): 133-139, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29210147

RESUMO

BACKGROUND: Several environmental and lifestyle factors have been associated with multiple sclerosis (MS) risk, including some pharmacological treatments. We systematically reviewed the literature on prescription drug exposure and MS risk. METHODS: Six databases were searched for original observational studies reporting drug exposure and MS risk published before 2017. RESULTS: Thirteen articles fulfilled inclusion criteria. Exposure to neither amiloride nor valproic acid was associated with MS (adjusted hazard ratio (adj.HR = 1.34;95% CI:0.81-2.20; adj.HR = 1.30;95%CI:0.44-3.80, respectively). Four studies explored oral contraceptive exposure and reported no association with MS; while a single study found an increased risk (odds ratio [adj.OR] = 1.52;95%CI:1.21-1.91). While penicillin exposure was associated with reduced risk of developing MS (adj.OR = 0.5;95%CI:0.3-0.9), a later study observed an elevated risk for penicillin (adj.OR = 1.21;95%CI:1.10-1.27) and all antibiotics (adj.OR = 1.41;95%CI:1.29-1.53), which was potentially attributed to underlying infection. Anti-tumor necrosis factor-alpha (TNFα) was not associated with MS risk in persons with inflammatory bowel disease (standard morbidity ratio = 4.2;95%CI:0.1-23.0) and arthritis (standardized incidence ratio = 1.38;95%CI:0.69-2.77); however, men exposed to anti-TNFα who also had arthritis and individuals with ankylosing spondylitis were at an increased risk (standardized incidence ratios = 3.91;95%CI:1.47-10.42 and 3.48;95%CI:1.45-8.37, respectively). A reduced risk of MS was observed with exposure to the beta2-adrenergic agonist fenoterol (adj.OR = 0.58;95%CI:0.45-0.76), and the sedating histamine 1-receptor antagonists (adj.OR = 0.2;95%CI:0.1-0.8), but not the non-sedating equivalent (adj.OR = 0.8;95%CI:0.4-1.6). CONCLUSIONS: The suggestion that some drugs may prevent MS is intriguing and warrants further study. In addition, further pharmacovigilance is needed to assess the safety of anti-TNFα drugs in specific populations in the context of MS risk.


Assuntos
Antirreumáticos/efeitos adversos , Esclerose Múltipla/epidemiologia , Medicamentos sob Prescrição/efeitos adversos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Antirreumáticos/administração & dosagem , Fenoterol/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Humanos , Incidência , Infliximab/administração & dosagem , Infliximab/efeitos adversos , Esclerose Múltipla/induzido quimicamente , Esclerose Múltipla/prevenção & controle , Estudos Observacionais como Assunto , Farmacovigilância , Medicamentos sob Prescrição/administração & dosagem
18.
BMC Musculoskelet Disord ; 19(1): 349, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261923

RESUMO

BACKGROUND: In this paper we investigate patients seeking care for a new diagnosis of shoulder osteoarthritis (OA) and the association between a patient's initial physician specialty choice and one-year surgical and conservative treatment utilization. METHODS: Using retrospective data from a single large regional healthcare system, we identified 572 individuals with a new diagnosis of shoulder OA and identified the specialty of the physician which was listed as the performing physician on the index shoulder visit. We assessed treatment utilization in the year following the index shoulder visit for patients initiating care with a non-orthopaedic physician (NOP) or an orthopaedic specialist (OS). Descriptive statistics were calculated for each group and subsequent one-year surgical and conservative treatment utilization was compared between groups. RESULTS: Of the 572 patients included in the study, 474 (83%) received care from an OS on the date of their index shoulder visit, while 98 (17%) received care from a NOP. There were no differences in baseline patient age, gender, BMI or pain scores between groups. OS patients reported longer symptom duration and a higher rate of comorbid shoulder diagnoses. Patients initiating care with an OS on average received their first treatment much faster than patients initiating care with NOP (16.3 days [95% CI, 12.8, 19.7] vs. 32.3 days [95% CI, 21.0, 43.6], Z = 4.9, p < 0.01). Additionally, patients initiating care with an OS had higher odds of receiving surgery (OR = 2.65, 95% CI: 1.42, 4.95) in the year following their index shoulder visit. CONCLUSIONS: Patients initiating care with an OS received treatment much faster and were treated with more invasive services over the year following their index shoulder visit. Future work should compare patient-reported outcomes across patient groups to assess whether more expensive and invasive treatments yield better outcomes for patients with shoulder OA.


Assuntos
Ortopedia/estatística & dados numéricos , Osteoartrite/terapia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Médicos/estatística & dados numéricos , Articulação do Ombro , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Retrospectivos , Tempo para o Tratamento , Adulto Jovem
19.
Am J Transplant ; 16(7): 2187-95, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26790369

RESUMO

Short-term outcomes of kidney transplantation have improved dramatically, but chronic rejection and regimen-related toxicity continue to compromise overall patient outcomes. Development of regulatory T cells (Tregs) as a means to decrease alloresponsiveness and limit the need for pharmacologic immunosuppression is an active area of preclinical and clinical investigation. Nevertheless, the immunomodulatory effects of end-stage renal disease on the efficacy of various strategies to generate and expand recipient Tregs for kidney transplantation are incompletely characterized. In this study, we show that Tregs can be successfully generated from either freshly isolated or previously cryopreserved uremic recipient (responder) and healthy donor (stimulator) peripheral blood mononuclear cells using the strategy of ex vivo costimulatory blockade with belatacept during mixed lymphocyte culture. Moreover, these Tregs maintain a CD3(+) CD4(+) CD25(+) CD127(lo) surface phenotype, high levels of intracellular FOXP3 and significant demethylation of the FOXP3 Treg-specific demethylation region on allorestimulation with donor stimulator cells. These data support evaluation of this simple, brief Treg production strategy in clinical trials of mismatched kidney transplantation.


Assuntos
Isoantígenos/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Leucócitos Mononucleares/imunologia , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante/imunologia , Abatacepte/imunologia , Adulto , Idoso , Feminino , Seguimentos , Fatores de Transcrição Forkhead/imunologia , Taxa de Filtração Glomerular , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Conduta Expectante
20.
Opt Express ; 24(10): 10512-26, 2016 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-27409874

RESUMO

We present a thorough investigation of surface deformation and thermal properties of high-damage threshold large-area semiconductor saturable absorber mirrors (SESAMs) designed for kilowatt average power laser oscillators. We compare temperature rise, thermal lensing, and surface deformation of standard SESAM samples and substrate-removed SESAMs contacted using different techniques. We demonstrate that for all cases the thermal effects scale linearly with the absorbed power, but the contacting technique critically affects the strength of the temperature rise and the thermal lens of the SESAMs (i.e. the slope of the linear change). Our best SESAMs are fabricated using a novel substrate-transfer direct bonding technique and show excellent surface flatness (with non-measureable radii of curvature (ROC), compared to astigmatic ROCs of up to 10 m for standard SESAMs), order-of-magnitude improved heat removal, and negligible deformation with absorbed power. This is achieved without altering the saturation behavior or the recovery parameters of the samples. These SESAMs will be a key enabling component for the next generation of kilowatt-level ultrafast oscillators.

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