Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 229
Filtrar
1.
Oncologist ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716777

RESUMO

BACKGROUND: Frailty is a dynamic syndrome characterized by reduced physiological reserve to maintain homeostasis. Prospective studies have reported frailty worsening in women with breast cancer during chemotherapy, with improvements following treatment. We evaluated whether the Faurot frailty index, a validated claims-based frailty measure, could identify changes in frailty during chemotherapy treatment and identified predictors of trajectory patterns. METHODS: We included women (65+ years) with stage I-III breast cancer undergoing adjuvant chemotherapy in the SEER-Medicare database (2003-2019). We estimated the Faurot frailty index (range: 0-1; higher scores indicate greater frailty) at chemotherapy initiation, 4 months postinitiation, and 10 months postinitiation. Changes in frailty were compared to a matched noncancer comparator cohort. We identified patterns of frailty trajectories during the year following chemotherapy initiation using K-means clustering. RESULTS: Twenty-one thousand five hundred and ninety-nine women initiated adjuvant chemotherapy. Mean claims-based frailty increased from 0.037 at initiation to 0.055 4 months postchemotherapy initiation and fell to 0.049 10 months postinitiation. Noncancer comparators experienced a small increase in claims-based frailty over time (0.055-0.062). We identified 6 trajectory patterns: a robust group (78%), 2 resilient groups (16%), and 3 nonresilient groups (6%). Black women and women with claims for home hospital beds, wheelchairs, and Parkinson's disease were more likely to experience nonresilient trajectories. CONCLUSIONS: We observed changes in a claims-based frailty index during chemotherapy that are consistent with prior studies using clinical measures of frailty and identified predictors of nonresilient frailty trajectories. Our study demonstrates the feasibility of using claims-based frailty indices to assess changes in frailty during cancer treatment.

2.
Med Care ; 62(5): 305-313, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498870

RESUMO

BACKGROUND: Frailty is an aging-related syndrome of reduced physiological reserve to maintain homeostasis. The Faurot frailty index has been validated as a Medicare claims-based proxy for predicting frailty using billing information from a user-specified ascertainment window. OBJECTIVES: We assessed the validity of the Faurot frailty index as a predictor of the frailty phenotype and 1-year mortality using varying frailty ascertainment windows. RESEARCH DESIGN: We identified older adults (66+ y) in Round 5 (2015) of the National Health and Aging Trends Study with Medicare claims linkage. Gold standard frailty was assessed using the frailty phenotype. We calculated the Faurot frailty index using 3, 6, 8, and 12 months of claims prior to the survey or all-available lookback. Model performance for each window in predicting the frailty phenotype was assessed by quantifying calibration and discrimination. Predictive performance for 1-year mortality was assessed by estimating risk differences across claims-based frailty strata. RESULTS: Among 4253 older adults, the 6 and 8-month windows had the best frailty phenotype calibration (calibration slopes: 0.88 and 0.87). All-available lookback had the best discrimination (C-statistic=0.780), but poor calibration. Mortality associations were strongest using a 3-month window and monotonically decreased with longer windows. Subgroup analyses revealed worse performance in Black and Hispanic individuals than counterparts. CONCLUSIONS: The optimal ascertainment window for the Faurot frailty index may depend on the clinical context, and researchers should consider tradeoffs between discrimination, calibration, and mortality. Sensitivity analyses using different durations can enhance the robustness of inferences. Research is needed to improve prediction across racial and ethnic groups.


Assuntos
Fragilidade , Humanos , Idoso , Estados Unidos/epidemiologia , Idoso Fragilizado , Medicare , Avaliação Geriátrica , Inquéritos e Questionários
4.
JCO Clin Cancer Inform ; 8: e2300214, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38320226

RESUMO

PURPOSE: Multiple myeloma (MM) is a prevalent hematologic malignancy in older adults, who often experience physical disability, increased health care usage, and reduced treatment tolerance. Home health (HH) services are frequently used by this group, but the relationship between disability, HH use, and MM treatment receipt is unclear. This study examines the connections between disability, treatment receipt, and survival outcomes in older adults with newly diagnosed MM using a nationwide data set. METHODS: The SEER-Medicare data set was used to identify adults aged 66 years and older diagnosed with MM from 2010 to 2017, who used HH services the year before diagnosis. Disability was assessed with the Outcome and Assessment Information Set, using a composite score derived from items related to ability to complete activities of daily living. Mortality, therapy receipt, and health care utilization patterns were evaluated. RESULTS: Of 37,280 older adults with MM, 6,850 (18.2%) used HH services before diagnosis. Moderate disability at HH assessment resulted in similar MM-directed therapy receipt as mild disability, with comparable health care usage after diagnosis to severe disability. HH users had a higher comorbidity burden and higher mortality (adjusted risk ratio for 3-year mortality: 1.59 [95% CI, 1.55 to 1.64]). Severe functional disability before diagnosis was strongly related to postdiagnosis mortality. CONCLUSION: Among older adults with MM receiving HH services, disability is a predictor of early mortality. Moderately disabled individuals undergo similar therapy intensity as the mildly disabled but experience increased acute care utilization. Previous HH use could identify patients with MM requiring intensive support during therapy initiation.


Assuntos
Pessoas com Deficiência , Mieloma Múltiplo , Idoso , Humanos , Estados Unidos , Medicare , Atividades Cotidianas , Estado Funcional
5.
Pharmacoepidemiol Drug Saf ; 33(1): e5703, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37743351

RESUMO

BACKGROUND: Sleep disorders are common among older adults, leading to high prevalence of over-the-counter and prescription sleep medication use. Socioeconomically disadvantaged individuals have higher prevalence of sleep disorders. Frequent use of sleep medications can increase the risk of falls. Little is known about the association between wealth and sleep medication use in older adults. METHODS: We conducted a cross-sectional analysis using a nationwide sample of 7603 Medicare beneficiaries (65+ years) from Round 1 (2011) of the National Health and Aging Trends Study. We measured self-reported wealth as the sum of assets (retirement savings, stocks/bonds, checking/savings accounts, business assets, and home value) minus liabilities (mortgage, credit card, and medical debt). Self-reported sleep medication use in the past month was categorized as frequent (5-7 nights/week), sometimes (1-4 nights/week), or never (0 night/week). We estimated differences in the prevalence of sleep medication use by quintiles of wealth using crude and adjusted binomial regression models. Individuals missing sleep medication information were excluded. RESULTS: Median wealth was $152 582 (IQR: $24 023-412 992). Sixteen percent reported frequent sleep medication use, 15% reported some use, and 70% reported no use. Frequent sleep medication use was more common in lower wealth quintiles (lowest: 20%, highest: 12%). Alternatively, some use was more common in higher wealth quintiles (lowest: 11%, highest: 18%). Results were similar after adjustment for demographic factors, anxiety, depression, and sleep disorders. CONCLUSIONS: In this study, less wealthy older adults had higher prevalence of frequent sleep medication use. This may lead to dependency or increased fall risk in this vulnerable population.


Assuntos
Medicamentos sob Prescrição , Transtornos do Sono-Vigília , Humanos , Idoso , Estados Unidos/epidemiologia , Medicare , Estudos Transversais , Medicamentos sem Prescrição , Medicamentos sob Prescrição/efeitos adversos , Sono , Transtornos do Sono-Vigília/tratamento farmacológico , Transtornos do Sono-Vigília/epidemiologia
6.
J Geriatr Oncol ; 14(8): 101602, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696241

RESUMO

INTRODUCTION: While prognosis for patients with chronic lymphocytic leukemia (CLL) has improved over time in younger adults, only modest improvements have occurred in older adults. We conducted a descriptive study of prognosis in older adults with CLL. MATERIALS AND METHODS: We used data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database from 2003 to 2016. We identified older adults (≥66 years) diagnosed with primary CLL between 2004 and 2015 (Overall Cohort). A subset who initiated CLL-directed therapy during the year following diagnosis was also identified (Treated Cohort). Both cohorts were matched to Medicare beneficiaries without cancer based on age, sex, and region. For each year from 2004 to 2013, three-year survival for patients with CLL and non-cancer comparators was described using Kaplan-Meier analysis. Inverse probability weighted Cox regression models were used to compare survival in the CLL and non-cancer comparator cohorts, accounting for demographic information and comorbidity and frailty indices. Among older adults with CLL, ten-year cause-specific cumulative mortality was estimated using Aalen-Johansen estimators that accounted for competing risks. Predictors of cause-specific mortality, including comorbidity and frailty burden, were assessed using sub-distribution hazards models. RESULTS: In the Overall Cohort, three-year survival increased non-monotonically from 71.4% in 2004 to 73.4% in 2013, with a peak of 74.4% in 2011, and was lower than survival in non-cancer comparators (78.3% in 2004 to 83.2% in 2013). In the Treated Cohort, three-year survival was 56.3% in 2004 and 56.5% in 2013, with a peak of 64.2% in 2011. Cox models suggested that survival in the Treated Cohort was approaching survival in non-cancer comparators after 2011 (hazard ratio = 1.04, 95% confidence interval, 0.93-1.17). Ten-year cumulative mortality was 68.6% in the Overall Cohort and 81.7% in the Treated Cohort, with most deaths attributed to non-CLL causes. In the sub-distribution hazards models, age, year of diagnosis, frailty, and comorbidities were all associated with prognosis. DISCUSSION: Prognosis in older adults has been stable over time and most patients with CLL die from non-CLL causes. CLL-directed treatment decision-making in older adults should consider age-related factors, such as comorbidity and frailty.


Assuntos
Fragilidade , Leucemia Linfocítica Crônica de Células B , Humanos , Idoso , Estados Unidos/epidemiologia , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/terapia , Estudos de Coortes , Medicare , Prognóstico
7.
Front Genet ; 14: 1216066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576554

RESUMO

Muscle damage and fibro-fatty replacement of skeletal muscles is a main pathologic feature of Duchenne muscular dystrophy (DMD) with more proximal muscles affected earlier and more distal affected later in the disease course, suggesting that different skeletal muscle groups possess distinctive characteristics that influence their susceptibility to disease. To explore transcriptomic factors driving differential gene expression and modulating DMD skeletal muscle severity, we characterized the transcriptome of vastus lateralis (VL), a more proximal and susceptible muscle, relative to tibialis anterior (TA), a more distal and protected muscle, in 15 healthy individuals using bulk RNA sequencing to identify gene expression differences that may mediate their relative susceptibility to damage with loss of dystrophin. Matching single nuclei RNA sequencing data was generated for 3 of the healthy individuals, to infer cell composition in the bulk RNA sequencing dataset and to improve mapping of differentially expressed genes to their cell source of expression. A total of 3,410 differentially expressed genes were identified and mapped to cell type using single nuclei RNA sequencing of muscle, including long non-coding RNAs and protein coding genes. There was an enrichment of genes involved in calcium release from the sarcoplasmic reticulum, particularly in the myofibers and these myofiber genes were higher in the VL. There was an enrichment of genes in "Collagen-Containing Extracellular Matrix" expressed by fibroblasts, endothelial, smooth muscle and pericytes, with most genes higher in the TA, as well as genes in "Regulation Of Apoptotic Process" expressed across all cell types. Previously reported genetic modifiers were also enriched within the differentially expressed genes. We also identify 6 genes with differential isoform usage between the VL and TA. Lastly, we integrate our findings with DMD RNA sequencing data from the TA, and identify "Collagen-Containing Extracellular Matrix" and "Negative Regulation Of Apoptotic Process" as differentially expressed between DMD compared to healthy. Collectively, these findings propose novel candidate mechanisms that may mediate differential muscle susceptibility in muscular dystrophies and provide new insight into potential therapeutic targets.

8.
Am J Epidemiol ; 192(12): 2085-2093, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37431778

RESUMO

The Faurot frailty index (FFI) is a validated algorithm that uses enrollment and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based billing information from Medicare claims data as a proxy for frailty. In October 2015, the US health-care system transitioned from the ICD-9-CM to the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM). Applying the Centers for Medicare and Medicaid Services General Equivalence Mappings, we translated diagnosis-based frailty indicator codes from the ICD-9-CM to the ICD-10-CM, followed by manual review. We used interrupted time-series analysis of Medicare data to assess the comparability of the pre- and posttransition FFI scores. In cohorts of beneficiaries enrolled in January 2015-2017 with 8-month frailty look-back periods, we estimated associations between the FFI and 1-year risk of aging-related outcomes (mortality, hospitalization, and admission to a skilled nursing facility). Updated indicators had similar prevalences as pretransition definitions. The median FFI scores and interquartile ranges (IQRs) for the predicted probability of frailty were similar before and after the International Classification of Diseases transition (pretransition: median, 0.034 (IQR, 0.02-0.07); posttransition: median, 0.038 (IQR, 0.02-0.09)). The updated FFI was associated with increased risks of mortality, hospitalization, and skilled nursing facility admission, similar to findings from the ICD-9-CM era. Studies of medical interventions in older adults using administrative claims should use validated indices, like the FFI, to mitigate confounding or assess effect-measure modification by frailty.


Assuntos
Fragilidade , Classificação Internacional de Doenças , Humanos , Idoso , Estados Unidos/epidemiologia , Fragilidade/epidemiologia , Medicare , Fatores de Risco , Hospitalização
9.
PLoS One ; 18(6): e0286984, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37289795

RESUMO

PURPOSE: Missing data is a key methodological consideration in longitudinal studies of aging. We described missing data challenges and potential methodological solutions using a case example describing five-year frailty state transitions in a cohort of older adults. METHODS: We used longitudinal data from the National Health and Aging Trends Study, a nationally-representative cohort of Medicare beneficiaries. We assessed the five components of the Fried frailty phenotype and classified frailty based on their number of components (robust: 0, prefrail: 1-2, frail: 3-5). One-, two-, and five-year frailty state transitions were defined as movements between frailty states or death. Missing frailty components were imputed using hot deck imputation. Inverse probability weights were used to account for potentially informative loss-to-follow-up. We conducted scenario analyses to test a range of assumptions related to missing data. RESULTS: Missing data were common for frailty components measured using physical assessments (walking speed, grip strength). At five years, 36% of individuals were lost-to-follow-up, differentially with respect to baseline frailty status. Assumptions for missing data mechanisms impacted inference regarding individuals improving or worsening in frailty. CONCLUSIONS: Missing data and loss-to-follow-up are common in longitudinal studies of aging. Robust epidemiologic methods can improve the rigor and interpretability of aging-related research.


Assuntos
Fragilidade , Idoso , Humanos , Estados Unidos , Fragilidade/epidemiologia , Idoso Fragilizado , Avaliação Geriátrica/métodos , Medicare , Estudos Longitudinais , Envelhecimento
11.
J Surg Res ; 288: 215-224, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37028209

RESUMO

INTRODUCTION: Feedback is an essential component in complex work environments. Different generations have been shown to have different sets of values, derived from societal and cultural changes. We hypothesize that generational differences may be associated with preferred feedback patterns among medical trainees and faculty in a large academic institution. METHODS: A survey was distributed to all students, residents/fellows, and faculty at a large academic medical institution from April 2020 through June 2020. Survey questions evaluated feedback methods for six domains: preparedness, performance, attitude, technical procedures, inpatient, and outpatient care. Participants selected a preferred feedback method for each category. Patient demographics and survey responses were described using frequency statistics. We compared differences in feedback preferences based on generation and field of practice. RESULTS: A total of 871 participants completed the survey. Preferred feedback patterns in the medical field do not seem to align with sociologic theories of generational gaps. Most participants preferred to receive direct feedback after an activity away from their team, irrespective of their age or medical specialty. Individuals preferred direct feedback during an activity in front of their team only for technical procedures. Compared to nonsurgeons, surgeons were more likely to prefer direct feedback in front of team members for preparedness, performance, and attitude. CONCLUSIONS: Generational membership is not significantly associated with preferred feedback patterns in this complex medical academic environment. Variations in feedback preferences are associated with field of practice that may be due to specialty-specific differences in culture and personality traits present within certain medical specialties, particularly surgery.


Assuntos
Internato e Residência , Estudantes de Medicina , Humanos , Retroalimentação , Centros Médicos Acadêmicos , Inquéritos e Questionários , Docentes
12.
Brain Commun ; 5(2): fcad030, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36895955

RESUMO

Spastic paraparesis has been described to occur in 13.7% of PSEN1 mutations and can be the presenting feature in 7.5%. In this paper, we describe a family with a particularly young onset of spastic paraparesis due to a novel mutation in PSEN1 (F388S). Three affected brothers underwent comprehensive imaging protocols, two underwent ophthalmological evaluations and one underwent neuropathological examination after his death at age 29. Age of onset was consistently at age 23 with spastic paraparesis, dysarthria and bradyphrenia. Pseudobulbar affect followed with progressive gait problems leading to loss of ambulation in the late 20s. Cerebrospinal fluid levels of amyloid-ß, tau and phosphorylated tau and florbetaben PET were consistent with Alzheimer's disease. Flortaucipir PET showed an uptake pattern atypical for Alzheimer's disease, with disproportionate signal in posterior brain areas. Diffusion tensor imaging showed decreased mean diffusivity in widespread areas of white matter but particularly in areas underlying the peri-Rolandic cortex and in the corticospinal tracts. These changes were more severe than those found in carriers of another PSEN1 mutation, which can cause spastic paraparesis at a later age (A431E), which were in turn more severe than among persons carrying autosomal dominant Alzheimer's disease mutations not causing spastic paraparesis. Neuropathological examination confirmed the presence of cotton wool plaques previously described in association with spastic parapresis and pallor and microgliosis in the corticospinal tract with severe amyloid-ß pathology in motor cortex but without unequivocal disproportionate neuronal loss or tau pathology. In vitro modelling of the effects of the mutation demonstrated increased production of longer length amyloid-ß peptides relative to shorter that predicted the young age of onset. In this paper, we provide imaging and neuropathological characterization of an extreme form of spastic paraparesis occurring in association with autosomal dominant Alzheimer's disease, demonstrating robust diffusion and pathological abnormalities in white matter. That the amyloid-ß profiles produced predicted the young age of onset suggests an amyloid-driven aetiology though the link between this and the white matter pathology remains undefined.

13.
J Pediatr Surg ; 58(3): 445-452, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36529566

RESUMO

BACKGROUND: Timing of inguinal hernia repair (IHR) in premature infants remains variable, yet the impact of IHR timing on procedure costs and recurrence is unclear. We sought to compare cost and recurrence rates of IHR in premature infants based on timing of repair. METHODS: We performed a retrospective cohort study using MarketScan insurance claims data from 2007 to 2018 to evaluate IHR occurring within 365 days of birth in preterm infants (gestational age [GA]<37 weeks at birth). Patients were stratified based on timing of IHR: those occurring during and after neonatal discharge. Hernia recurrences within one year following IHR were identified. Patient demographic characteristics and costs were compared between groups. Time to recurrence and cumulative recurrence hazards were estimated using Kaplan Meier analysis and Cox proportional hazards regression. RESULTS: We identified 3,662 preterm infants with IHR within 365 days of birth; 1,054(28.8%) occurred early. Infants with IHR during NICU stay were more likely to have GA at birth≤32 weeks (74.7% vs. 37.2%; p<0.01) and birthweight<1500 g (83.0% vs. 40.3%; p<0.01) compared to post-NICU IHR. The hernia recurrence rate was higher and total procedure costs lower in early IHR. Early IHR (HR:1.86, 95% CI: 1.56-2.22), incarcerated/strangulated hernia (HR:1.86, 95% CI:1.49-2.32), GA≤32 weeks (HR: 1.40, 95% CI: 1.19-1.65), and congenital anomalies (HR: 1.32, 95% CI: 1.12-1.57) were predictors of hernia recurrence. CONCLUSION: Using insurance claims data, IHR performed during initial neonatal admission was associated with lower cost, but higher recurrence rate, when compared to delayed repairs in preterm infants. TYPE OF STUDY: Retrospective study LEVEL OF EVIDENCE: Level III.


Assuntos
Hérnia Inguinal , Recém-Nascido Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Estudos Retrospectivos , Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Idade Gestacional , Recidiva
15.
JTCVS Open ; 16: 689-697, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38204678

RESUMO

Objectives: Limited data on performing bilateral pulmonary artery banding (BPAB) before stage 1 Norwood procedure suggest that some patients may benefit through the postponement of the major cardiopulmonary bypass procedure. The objective of this study was to evaluate the effectiveness of BPAB in the surgical management of high-risk patients with hypoplastic left heart syndrome (HLHS). Methods: A retrospective review of all high-risk neonates with HLHS who underwent BPAB at our institution was performed. No patients, including those with intact or highly restrictive atrial septum (IAS), were excluded. Results: Between October 2015 and April 2021, 49 neonates with HLHS (including 6 with IAS) underwent BPAB, 40 of whom progressed to the Norwood procedure. Risk factors for not progressing to the Norwood procedure after BPAP include low birth weight (P = .043), the presence of multiple extracardiac anomalies (P = .005), and the presence of genetic disorders (P = .028). Operative mortality was 7.5% (3/40). IAS was associated with operative mortality (P = .022). Conclusions: The strategy of BPAB prestage 1 Norwood procedure was successful in identifying at-risk patients and improving Norwood survival. Although not all patients will need this hybrid approach, a significant number can be expected to benefit from this tactic. These results support the need for a substantial hybrid strategy, in addition to a primary stage 1 Norwood surgical strategy, in the management of HLHS.

16.
medRxiv ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38234782

RESUMO

Autism Spectrum Disorder (ASD) exhibits an ~4:1 male-to-female sex bias and is characterized by early-onset impairment of social/communication skills, restricted interests, and stereotyped behaviors. Disruption of the Xp22.11 locus has been associated with ASD in males. This locus includes the three-exon PTCHD1 gene, an adjacent multi-isoform long noncoding RNA (lncRNA) named PTCHD1-AS (spanning ~1Mb), and a poorly characterized single-exon RNA helicase named DDX53 that is intronic to PTCHD1-AS. While the relationship between PTCHD1/PTCHD1-AS and ASD is being studied, the role of DDX53 has not been examined, in part because there is no apparent functional murine orthologue. Through clinical testing, here, we identified 6 males and 1 female with ASD from 6 unrelated families carrying rare, predicted-damaging or loss-of-function variants in DDX53. Then, we examined databases, including the Autism Speaks MSSNG and Simons Foundation Autism Research Initiative, as well as population controls. We identified 24 additional individuals with ASD harboring rare, damaging DDX53 variations, including the same variants detected in two families from the original clinical analysis. In this extended cohort of 31 participants with ASD (28 male, 3 female), we identified 25 mostly maternally-inherited variations in DDX53, including 18 missense changes, 2 truncating variants, 2 in-frame variants, 2 deletions in the 3' UTR and 1 copy number deletion. Our findings in humans support a direct link between DDX53 and ASD, which will be important in clinical genetic testing. These same autism-related findings, coupled with the observation that a functional orthologous gene is not found in mouse, may also influence the design and interpretation of murine-modelling of ASD.

17.
Commun Biol ; 5(1): 989, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123393

RESUMO

In Duchenne muscular dystrophy, dystrophin loss leads to chronic muscle damage, dysregulation of repair, fibro-fatty replacement, and weakness. We develop methodology to efficiently isolate individual nuclei from minute quantities of frozen skeletal muscle, allowing single nuclei sequencing of irreplaceable archival samples and from very small samples. We apply this method to identify cell and gene expression dynamics within human DMD and mdx mouse muscle, characterizing effects of dystrophin rescue by exon skipping therapy at single nuclei resolution. DMD exon 23 skipping events are directly observed and increased in myonuclei from treated mice. We describe partial rescue of type IIa and IIx myofibers, expansion of an MDSC-like myeloid population, recovery of repair/remodeling M2-macrophage, and repression of inflammatory POSTN1 + fibroblasts in response to exon skipping and partial dystrophin restoration. Use of this method enables exploration of cellular and transcriptomic mechanisms of dystrophin loss and repair within an intact muscle environment. Our initial findings will scaffold our future work to more directly examine muscular dystrophies and putative recovery pathways.


Assuntos
Distrofina , Distrofia Muscular de Duchenne , Animais , Distrofina/genética , Humanos , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/genética , Transcriptoma
18.
Cancer Epidemiol Biomarkers Prev ; 31(11): 2079-2086, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35984990

RESUMO

BACKGROUND: Studies evaluating the effects of cancer treatments are prone to immortal time bias that, if unaddressed, can lead to treatments appearing more beneficial than they are. METHODS: To demonstrate the impact of immortal time bias, we compared results across several analytic approaches (dichotomous exposure, dichotomous exposure excluding immortal time, time-varying exposure, landmark analysis, clone-censor-weight method), using surgical resection among women with metastatic breast cancer as an example. All adult women diagnosed with incident metastatic breast cancer from 2013-2016 in the National Cancer Database were included. To quantify immortal time bias, we also conducted a simulation study where the "true" relationship between surgical resection and mortality was known. RESULTS: 24,329 women (median age 61, IQR 51-71) were included, and 24% underwent surgical resection. The largest association between resection and mortality was observed when using a dichotomized exposure [HR, 0.54; 95% confidence interval (CI), 0.51-0.57], followed by dichotomous with exclusion of immortal time (HR, 0.62; 95% CI, 0.59-0.65). Results from the time-varying exposure, landmark, and clone-censor-weight method analyses were closer to the null (HR, 0.67-0.84). Results from the plasmode simulation found that the time-varying exposure, landmark, and clone-censor-weight method models all produced unbiased HRs (bias -0.003 to 0.016). Both standard dichotomous exposure (HR, 0.84; bias, -0.177) and dichotomous with exclusion of immortal time (HR, 0.93; bias, -0.074) produced meaningfully biased estimates. CONCLUSIONS: Researchers should use time-varying exposures with a treatment assessment window or the clone-censor-weight method when immortal time is present. IMPACT: Using methods that appropriately account for immortal time will improve evidence and decision-making from research using real-world data.


Assuntos
Neoplasias da Mama , Oncologia Cirúrgica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Fatores de Tempo , Viés , Projetos de Pesquisa
19.
Methods Mol Biol ; 2536: 309-346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35819612

RESUMO

Fungal and oomycete plant pathogens are responsible for the devastation of various ecosystems such as forest and crop species worldwide. In an effort to protect such natural resources for food, lumber, etc., early detection of non-indigenous phytopathogenic fungi in new areas is a key approach in managing threats at their source of introduction. A workflow was developed using high-throughput sequencing (HTS), more specifically metabarcoding, a method for rapid and higher throughput species screening near high-risk areas, and over larger geographical spaces. Biomonitoring of fungal and oomycete entities of plant pathogens (e.g., airborne spores) regained from environmental samples and their processing by metabarcoding is thoroughly described here. The amplicon-based approach goes from DNA and sequencing library preparation using custom-designed polymerase chain reaction (PCR) fusion primers that target the internal transcribed spacer 1 (ITS1) from fungi and oomycetes and extends to multiplex HTS with the Ion Torrent platform. In addition, a brief and simplified overview of the bioinformatics analysis pipeline and other available tools required to process amplicon sequences is also included. The raw data obtained and processed enable users to select a bioinformatics pipeline in order to directly perform biodiversity, presence/absence, geographical distribution, and abundance analyses through the tools suggested, which allows for accelerated identification of phytopathogens of interest.


Assuntos
Monitoramento Biológico , Oomicetos , Primers do DNA/genética , Ecossistema , Oomicetos/genética , Plantas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...