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1.
Dela J Public Health ; 10(1): 30-38, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38572140

RESUMO

Objective: To describe the process of engaging community, caregiver, and youth partners in codeveloping an intervention to promote equitable uptake of the COVID-19 vaccine in non-Hispanic Black (Black) and Hispanic youth who experience higher rates of COVID-19 transmission, morbidity, and mortality but were less likely to receive the COVID-19 vaccine. Methods: A team of 11 Black and Hispanic community partners was assembled to codevelop intervention strategies with our interdisciplinary research team. We used a mixed-methods crowdsourcing approach with Black and Hispanic youth (n=15) and caregivers of Black and Hispanic youth (n=20) who had not yet been vaccinated against COVID-19, recruited from primary care clinics, to elicit perspectives on the acceptability of these intervention strategies. Results: We codeveloped five strategies: (1) community-tailored handouts and posters, (2) videos featuring local youth, (3) family-centered language to offer vaccines in the primary care clinic, (4) communication-skills training for primary care providers, and (5) use of community health workers to counsel families about the vaccine. The majority (56-96.9%) of youth and caregivers rated each of these strategies as acceptable, especially because they addressed common concerns and facilitated shared decision-making. Conclusions: Engaging community and family partners led to the co-development of culturally- and locally-tailored strategies to promote dialogue and shared decision-making about the COVID-19 vaccine. This process can be used to codevelop interventions to address other forms of public health disparities. Policy Implications: Intervention strategies that promote dialogues with trusted healthcare providers and support shared decision-making are acceptable strategies to promote COVID-19 vaccine uptake among youth from historically underserved communities. Stakeholder-engaged methods may also help in the development of interventions to address other forms of health disparities.

3.
Pancreas ; 53(2): e176-e179, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194634

RESUMO

OBJECTIVE: Pancreata recovered for research are included as a success (or positive) in the Centers for Medicare and Medicaid Services' (CMS) donation and organ transplantation rate metrics for recertification of organ procurement organizations (OPOs). MATERIALS AND METHODS: Given these metrics directly incentivize recovery of pancreata for research, this study tracks trends in recovery of pancreata for research across the implementation of the CMS metrics. RESULTS: In the 26 months before the December 2, 2020, publication of the CMS metrics, research pancreata as a percent of organs transplanted, including research pancreata, was 1.7% nationally, including as much as 10.8% of organs transplanted within any OPO. In the 26 months after the CMS metrics were published, research pancreata increased to 5.1% of organs counted as transplants nationally, including as much as 20.3% within any OPO. If research pancreata were excluded from the CMS metrics, 6 OPOs would change their CMS evaluation status for recertification purposes: 2 would move up a tier and 4 would move down a tier. CONCLUSIONS: Procurement of research pancreata has increased since the publication of the CMS performance metrics, OPOs vary in their recovery of pancreata for research, and recovery of pancreata for research can affect recertification of OPOs.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Idoso , Humanos , Estados Unidos , Centers for Medicare and Medicaid Services, U.S. , Medicare , Doadores de Tecidos
4.
Sensors (Basel) ; 23(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37177650

RESUMO

Three-dimensional force plates are important tools for biomechanics discovery and sports performance practice. However, currently, available 3D force plates lack portability and are often cost-prohibitive. To address this, a recently discovered 3D force sensor technology was used in the fabrication of a prototype force plate. Thirteen participants performed bodyweight and weighted lunges and squats on the prototype force plate and a standard 3D force plate positioned in series to compare forces measured by both force plates and validate the technology. For the lunges, there was excellent agreement between the experimental force plate and the standard force plate in the X-, Y-, and Z-axes (r = 0.950-0.999, p < 0.001). For the squats, there was excellent agreement between the force plates in the Z-axis (r = 0.996, p < 0.001). Across axes and movements, root mean square error (RMSE) ranged from 1.17% to 5.36% between force plates. Although the current prototype force plate is limited in sampling rate, the low RMSEs and extremely high agreement in peak forces provide confidence the novel force sensors have utility in constructing cost-effective and versatile use-case 3D force plates.


Assuntos
Fenômenos Mecânicos , Movimento , Humanos , Análise Custo-Benefício , Fenômenos Biomecânicos , Postura
5.
Am J Transplant ; 23(2 Suppl 1): S443-S474, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37132344

RESUMO

The Scientific Registry of Transplant Recipients uses data collected by the Organ Procurement and Transplantation Network to calculate metrics such as donation rate, organ yield, and rate of organs recovered for transplant but not transplanted (ie, nonuse). In 2021, there were 13,862 deceased donors, a 10.1% increase from 12,588 in 2020, and an increase from 11,870 in 2019; this number has been increasing since 2010. The number of deceased donor transplants increased to 41,346 transplants in 2021, a 5.9% increase from 39,028 in 2020; this number has been increasing since 2012. The increase may be due in part to the rising number of deaths of young people amid the ongoing opioid epidemic. The number of organs transplanted included 9,702 left kidneys, 9,509 right kidneys, 551 en bloc kidneys, 964 pancreata, 8,595 livers, 96 intestines, 3,861 hearts, and 2,443 lungs. Compared with 2019, transplants of all organs except lungs increased in 2021, which is remarkable as this occurred despite the COVID-19 pandemic. In 2021, 2,951 left kidneys, 3,149 right kidneys, 184 en bloc kidneys, 343 pancreata, 945 liver, 1 intestine, 39 hearts, and 188 lungs were not used. These numbers suggest an opportunity to increase numbers of transplants by reducing nonused organs. Despite the pandemic, there was no dramatic increase in number of nonused organs and there was an increase in total numbers of donors and transplants. The new Centers for Medicare & Medicaid Services metrics for donation rate and transplant rate have also been described and vary across organ procurement organizations; the donation rate metric varied from 5.82 to 19.14 and the transplant rate metric varied from 18.7 to 60.0.


Assuntos
COVID-19 , Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Idoso , Humanos , Estados Unidos , Adolescente , Pandemias , Medicare , Doadores de Tecidos
6.
Proc Natl Acad Sci U S A ; 120(18): e2120252120, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094134

RESUMO

Streams in urbanizing watersheds are threatened by economic development that can lead to excessive sediment erosion and surface runoff. These anthropogenic stressors diminish valuable ecosystem services and result in pervasive degradation commonly referred to as "urban stream syndrome." Understanding how the public perceives and values improvements in stream conditions is necessary to support efforts to quantify the economic benefits of water quality improvements. We develop an ecological production framework that translates measurable indicators of stream water quality into ecological endpoints. Our interdisciplinary approach integrates a predictive hierarchical water quality model that is well suited for sparse data environments, an expert elicitation that translates measurable water quality indicators into ecological endpoints that focus group participants identified as most relevant, and a stated preference survey that elicits the public's willingness to pay for changes in these endpoints. To illustrate our methods, we develop an application to the Upper Neuse River Watershed located in the rapidly developing Triangle region of North Carolina (the United States). Our results suggest, for example, that residents are willing to pay roughly $127 per household and $54 million per year in aggregate (2021 US$) for water quality improvements resulting from a stylized intervention that increases stream bank canopy cover by 25% and decreases runoff from impervious surfaces, leading to improvements in water quality and ecological endpoints for local streams. Although the three components of our analysis are conducted with data from North Carolina, we discuss how our findings are generalizable to urban and urbanizing areas across the larger Piedmont ecoregion of the Eastern United States.

9.
Am J Clin Pathol ; 155(6): 863-872, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33386737

RESUMO

OBJECTIVES: This study was undertaken to explore the feasibility of assessing platelet dense granule release in response to platelet stimuli, using less than 1 mL of whole blood (WB). METHODS: Optimization of the luciferin-luciferase (LL) assay for ATP release, together with additional modifications, was applied to 1:10 diluted WB. RESULTS: LL assay optimization using nonstirred 1:10 diluted WB resulted in dense granule ATP release in response to thrombin receptor-activating peptide (TRAP) of similar magnitude to that observed using stirred platelet-rich plasma. Stirring of the 1:10 diluted WB restored collagen-induced dense granule secretion. Addition of lyophilized, formalin-fixed platelets, together with stirring, restored dense granule secretion responsiveness to ADP. TRAP, ADP, and collagen all stimulated ATP release in 1:10 diluted WB under the optimized conditions of this study at levels close to those observed using platelet-rich plasma. Blood sample reconstitution experiments offer hope that this assay may prove robust down to WB platelet counts as low as 50 × 103/µL. CONCLUSIONS: Platelet dense granule release in response to a number of classic stimuli, including ADP, was accomplished from less than 1 mL WB with minimal specimen processing, using widely available reagents and instrumentation.


Assuntos
Trifosfato de Adenosina/sangue , Plaquetas/efeitos dos fármacos , Formaldeído/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Trombina/farmacologia , Plaquetas/fisiologia , Humanos , Contagem de Plaquetas
10.
Dela J Public Health ; 7(5): 64-71, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35619974

RESUMO

Objective: To describe sociodemographic disparities in caregiver beliefs about the COVID-19 vaccine for their children. Methods: This was a cross-sectional study, linking caregiver-reported data to geocoded sociodemographic data from child EHRs. Caregivers of children receiving care in a Delaware pediatric healthcare system were invited to complete a survey about COVID-19 vaccine beliefs from March 19 to April 16, 2021. Results: 1499 caregivers participated (18% Black, 11% Hispanic, 32% public insurance, 12% rural). 54% of caregivers intended to vaccinate their children, while 34% were unsure and 12% would not. Caregivers of younger children (aOR 3.70, CI 2.36-5.79), Black children (aOR 2.11, CI 1.50-2.96), and from disadvantaged communities (aOR 1.59, CI 1.05-2.42) were more likely to be unsure and not vaccinate their children. Caregivers from rural communities were more likely not to vaccinate their children (aOR 2.51, CI 1.56-4.05). Fewer caregivers of younger children, Black children, and from disadvantaged communities believed in the safety or efficacy of the vaccines (p < 0.001), while fewer caregivers of younger children and from rural communities believed in their children's susceptibility to COVID-19 or risk of getting severe disease from COVID-19 (p < 0.05). While the majority (72%) of caregivers were influenced by health experts, fewer from communities of color and disadvantaged communities were (p<0.001). Conclusions: Caregivers of younger children and from communities of color, rural communities, and disadvantaged communities in Delaware expressed more COVID-19 vaccine hesitancy. Policy implications: This study explores beliefs of different communities in Delaware, which are important to tailoring public health messaging and strategies to increase vaccine uptake in these communities.

11.
Proc Natl Acad Sci U S A ; 117(22): 11987-11994, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32424082

RESUMO

Chronic hepatitis C virus (HCV) infection is a leading cause of cirrhosis worldwide and kills more Americans than 59 other infections, including HIV and tuberculosis, combined. While direct-acting antiviral (DAA) treatments are effective, limited uptake of therapy, particularly in high-risk groups, remains a substantial barrier to eliminating HCV. We developed a long-acting DAA system (LA-DAAS) capable of prolonged dosing and explored its cost-effectiveness. We designed a retrievable coil-shaped LA-DAAS compatible with nasogastric tube administration and the capacity to encapsulate and release gram levels of drugs while resident in the stomach. We formulated DAAs in drug-polymer pills and studied the release kinetics for 1 mo in vitro and in vivo in a swine model. The LA-DAAS was equipped with ethanol and temperature sensors linked via Bluetooth to a phone application to provide patient engagement. We then performed a cost-effectiveness analysis comparing LA-DAAS to DAA alone in various patient groups, including people who inject drugs. Tunable release kinetics of DAAs was enabled for 1 mo with drug-polymer pills in vitro, and the LA-DAAS safely and successfully provided at least month-long release of sofosbuvir in vivo. Temperature and alcohol sensors could interface with external sources for at least 1 mo. The LA-DAAS was cost-effective compared to DAA therapy alone in all groups considered (base case incremental cost-effectiveness ratio $39,800). We believe that the LA-DAA system can provide a cost-effective and patient-centric method for HCV treatment, including in high-risk populations who are currently undertreated.


Assuntos
Antivirais/administração & dosagem , Sistemas de Liberação de Medicamentos , Hepatite C Crônica/tratamento farmacológico , Animais , Antivirais/farmacocinética , Benzimidazóis/administração & dosagem , Benzimidazóis/farmacocinética , Carbamatos , Análise Custo-Benefício , Modelos Animais de Doenças , Portadores de Fármacos/farmacocinética , Sistemas de Liberação de Medicamentos/economia , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Fluorenos/administração & dosagem , Fluorenos/farmacocinética , Hepacivirus/efeitos dos fármacos , Imidazóis/administração & dosagem , Imidazóis/farmacocinética , Cirrose Hepática/tratamento farmacológico , Modelos Animais , Pirrolidinas , Ribavirina/administração & dosagem , Ribavirina/farmacocinética , Sofosbuvir/administração & dosagem , Sofosbuvir/farmacocinética , Suínos , Valina/análogos & derivados
13.
J Phys Act Health ; 16(12): 1163-1174, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31651411

RESUMO

BACKGROUND: This study tested for differences in personal, social, and environmental correlates of moderate to vigorous physical activity (MVPA) across ethnicity/race in male and female adolescents. METHODS: Self-reported MVPA and 47 potential correlates of MVPA were measured in an ethnically/racially diverse cross-sectional sample of adolescents, in Minnesota, who participated in EAT-2010 (Eating and Activity in Teens). Interactions of potential correlates with ethnicity/race on MVPA were tested in linear hierarchical regression models in boys and girls. RESULTS: Boys reported 1.7 more weekly hours of MVPA than girls. White adolescents reported 1.1 to 2.1 more weekly hours of MVPA than nonwhite adolescents. Among girls, neighborhood road connectivity was negatively correlated with MVPA among Hispanic and Asian participants. Among boys, sports participation was positively correlated with MVPA among all ethnicities/races, except Asians. Home media equipment was positively correlated with MVPA among Hispanic boys, but negatively correlated among white boys. CONCLUSIONS: A few correlates of physical activity among adolescents differed intersectionally by ethnicity/race and sex. Sports participation and home media equipment may have differing impacts on physical activity across ethnicities and races in boys, whereas neighborhood features like road connectivity may have differing impacts on physical activity across ethnicities and races in girls.


Assuntos
Etnicidade/psicologia , Exercício Físico/psicologia , Esportes/psicologia , Adolescente , Doença Crônica/prevenção & controle , Estudos Transversais , Feminino , Hispânico ou Latino , Humanos , Modelos Lineares , Masculino , Minnesota , Características de Residência , Fatores Sexuais , Inquéritos e Questionários
14.
Sci Transl Med ; 11(483)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867322

RESUMO

Multigram drug depot systems for extended drug release could transform our capacity to effectively treat patients across a myriad of diseases. For example, tuberculosis (TB) requires multimonth courses of daily multigram doses for treatment. To address the challenge of prolonged dosing for regimens requiring multigram drug dosing, we developed a gastric resident system delivered through the nasogastric route that was capable of safely encapsulating and releasing grams of antibiotics over a period of weeks. Initial preclinical safety and drug release were demonstrated in a swine model with a panel of TB antibiotics. We anticipate multiple applications in the field of infectious diseases, as well as for other indications where multigram depots could impart meaningful benefits to patients, helping maximize adherence to their medication.


Assuntos
Antituberculosos/uso terapêutico , Sistemas de Liberação de Medicamentos , Estômago/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Antituberculosos/farmacologia , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Doxiciclina/uso terapêutico , Sistemas de Liberação de Medicamentos/economia , Liberação Controlada de Fármacos , Humanos , Suínos
15.
Med Sci Sports Exerc ; 51(4): 663-670, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30673690

RESUMO

INTRODUCTION: Common life events, such as getting married or gaining employment, may be opportunities to intervene on health behaviors like physical activity. The purpose of this study was to determine the changes in moderate-to-vigorous physical activity (MVPA) associated with several common life events from adolescence to young adulthood. METHODS: Participants in Project EAT (ages 11 to 18 yr at baseline and 25 to 36 yr at wave 4) were surveyed at four timepoints from 1998 to 2016. Questions included marital status, employment status, postsecondary education completion and enrollment, and living situation between each wave. Linear regression was used to model the effect of each life event on change in self-reported MVPA. Post hoc mediation analysis was conducted to examine whether having a child mediated the effect of getting married on the change in MVPA. RESULTS: Average MVPA declined from 6.5 h·wk at baseline to 4.3 h·wk at wave 4. Having a child was associated with a significant decrease in MVPA between waves 2 and 3 and between waves 3 and 4. Getting married and leaving parents' home were associated with significant decreases in MVPA between waves 3 and 4. Having a child both mediated and moderated the effect of getting married on MVPA. CONCLUSIONS: This study provides evidence that MVPA declines both after getting married and after having a child and that these effects are not independent. Interventions to maintain or increase MVPA could profitably target couples planning to get married or have a child.


Assuntos
Exercício Físico/psicologia , Comportamentos Relacionados com a Saúde , Acontecimentos que Mudam a Vida , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Casamento , Pais , Fatores Raciais , Fatores Sexuais , Fatores Socioeconômicos
16.
Thorax ; 73(8): 713-722, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29680821

RESUMO

BACKGROUND: Previous models of Hospital at Home (HAH) for COPD exacerbation (ECOPD) were limited by the lack of a reliable prognostic score to guide patient selection. Approximately 50% of hospitalised patients have a low mortality risk by DECAF, thus are potentially suitable. METHODS: In a non-inferiority randomised controlled trial, 118 patients admitted with a low-risk ECOPD (DECAF 0 or 1) were recruited to HAH or usual care (UC). The primary outcome was health and social costs at 90 days. RESULTS: Mean 90-day costs were £1016 lower in HAH, but the one-sided 95% CI crossed the non-inferiority limit of £150 (CI -2343 to 312). Savings were primarily due to reduced hospital bed days: HAH=1 (IQR 1-7), UC=5 (IQR 2-12) (P=0.001). Length of stay during the index admission in UC was only 3 days, which was 2 days shorter than expected. Based on quality-adjusted life years, the probability of HAH being cost-effective was 90%. There was one death within 90 days in each arm, readmission rates were similar and 90% of patients preferred HAH for subsequent ECOPD. CONCLUSION: HAH selected by low-risk DECAF score was safe, clinically effective, cost-effective, and preferred by most patients. Compared with earlier models, selection is simpler and approximately twice as many patients are eligible. The introduction of DECAF was associated with a fall in UC length of stay without adverse outcome, supporting use of DECAF to direct early discharge. TRIAL REGISTRATION NUMBER: Registered prospectively ISRCTN29082260.


Assuntos
Serviços de Assistência Domiciliar/economia , Doença Pulmonar Obstrutiva Crônica/terapia , Idoso , Análise Custo-Benefício , Feminino , Custos Hospitalares , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Satisfação do Paciente , Seleção de Pacientes , Prognóstico , Estudos Prospectivos , Fatores de Risco
17.
J Am Vet Med Assoc ; 252(4): 448-456, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29393745

RESUMO

OBJECTIVE To evaluate platinum content in biodegradable carboplatin-impregnated beads and retrospectively assess tolerability and outcome data for dogs treated by intralesional placement of such beads following surgical excision of subcutaneous sarcomas. DESIGN Evaluation study and retrospective case series. SAMPLE 9 carboplatin-impregnated beads and 29 client-owned dogs. PROCEDURES Platinum content in 9 carboplatin-impregnated beads from 3 lots was measured by spectrophotometry, and calculated carboplatin content was compared with the labeled content. Medical records were searched to identify dogs with subcutaneous sarcomas for which treatment included placement of carboplatin-impregnated beads between 2011 and 2014. Signalment, tumor characteristics, surgical and histologic data, adverse events, and local recurrences were recorded. Associations between variables of interest and adverse events or local disease-free interval were analyzed. RESULTS In vitro analysis identified a mean ± SD platinum content of 5.38 ± 0.97 mg/bead. Calculated carboplatin content (10.24 ± 1.84 mg/bead) was significantly greater than the labeled amount (4.6 mg/bead). Bead weight and total platinum content differed significantly among lots, but platinum content per bead weight did not. Mild-to-moderate local adverse events were reported for 11 of 29 tumors; all resolved without additional surgery. No dogs had signs of systemic toxicosis. Overall local disease-free rates 1, 2, and 3 years after surgery were 70%, 70%, and 58%, respectively, as determined by Kaplan-Meier analysis. CONCLUSIONS AND CLINICAL RELEVANCE Carboplatin-impregnated beads were well tolerated; however, results of in vitro tests indicated that caution is needed because of manufacturing inconsistencies.


Assuntos
Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Doenças do Cão/tratamento farmacológico , Recidiva Local de Neoplasia/veterinária , Sarcoma/veterinária , Neoplasias de Tecidos Moles/veterinária , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/análise , Carboplatina/administração & dosagem , Carboplatina/análise , Terapia Combinada , Intervalo Livre de Doença , Doenças do Cão/mortalidade , Doenças do Cão/cirurgia , Cães , Implantes de Medicamento/administração & dosagem , Implantes de Medicamento/análise , Implantes de Medicamento/uso terapêutico , Feminino , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , New Jersey , Estudos Retrospectivos , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Resultado do Tratamento
18.
J Phys Act Health ; 15(5): 345-354, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29421966

RESUMO

BACKGROUND: Interventions to raise population physical activity generally show modest effects; one possible reason is that trends and determinants of moderate to vigorous physical activity (MVPA) differ between population subgroups. This study examined differences in trends and determinants of reported MVPA by ethnicity/race and sex in a 15-year longitudinal study. METHODS: Participants (n = 2092) in the Project Eating and Activity in Teens and Young Adults study were surveyed on MVPA behavior and potential determinants from adolescence to young adulthood. Generalized estimating equations were used to model age trends in MVPA and associations with determinants. RESULTS: Mean MVPA declined by 2.1 hours per week over 15 years of follow-up from adolescence to young adulthood. Asian males reported the lowest levels of MVPA at each age. Nonwhite females reported less MVPA than white females at each age. The association of body mass index (BMI) with MVPA differed by sex and ethnicity/race. Asian males and females showed lower levels of MVPA at both low and high BMI. CONCLUSIONS: Interventions to increase MVPA may need to begin earlier among Asian men and nonwhite women than among other groups. Asian adolescents with lower BMI show lower MVPA and may benefit from additional intervention efforts compared with Asian adolescents with normal BMI.


Assuntos
Exercício Físico/psicologia , Adolescente , Criança , Etnicidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Grupos Raciais , Fatores Sexuais
19.
J Strength Cond Res ; 31(9): 2355-2362, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28820846

RESUMO

Fry, AC, Housh, TJ, Cramer, JB, Weir, JP, Beck, TW, Schilling, BK, Miller, JD, and Nicoll, JX. Noninvasive assessment of skeletal muscle myosin heavy chain expression in trained and untrained men. J Strength Cond Res 31(9): 2355-2362, 2017-Numerous conditions and types of physical activity (e.g., exercise, aging, and muscle-related diseases) can influence muscle fiber types and the proteins expressed. To date, muscle fibers can only be characterized by actually obtaining a tissue sample using the invasive muscle biopsy procedure. Mechanomyography (MMG) is the assessment of the vibration properties of contracting skeletal muscle and has been proposed as a possible noninvasive method for muscle fiber analysis. Therefore, the purpose of this project was to examine the feasibility of using MMG and muscle performance measures to noninvasively assess muscle fiber characteristics. Fifteen men (5 endurance-trained, 5 weight-trained, and 5 sedentary) provided muscle samples from their vastus lateralis muscle. These samples were analyzed for relative myosin heavy chain (MHC) protein expression, which is highly correlated with % muscle fiber type areas. Additionally, each subject performed several muscle performance tests, and MMG of the quadriceps was assessed during a knee extension exercise. Multiple regression was used to develop prediction equations for determining relative muscle content of MHC types I, IIa, and IIx. A combination of MMG and knee extension performance variables estimated types I, IIa, and IIx MHCs with approximately 80% accuracy. Although preliminary, these data suggest that muscle performance tests in addition to MMG assessments during a simple muscle performance task (knee extension) can be used to estimate muscle fiber type composition in a healthy male population. Such methods could ultimately be used to noninvasively monitor muscle health and fitness.


Assuntos
Exercício Físico/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Cadeias Pesadas de Miosina/biossíntese , Músculo Quadríceps/metabolismo , Adulto , Biópsia , Humanos , Masculino , Adulto Jovem
20.
Technol Cancer Res Treat ; 15(1): 196-202, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25633137

RESUMO

Stereotactic body radiation therapy (SBRT) is an emerging technology for the treatment of spinal metastases, although the dosimetric impact of the calculation method on spinal dose distribution is unknown. This study attempts to determine whether CyberKnife (CK)-based SBRT using a Ray Tracing (RyTc) algorithm is comparable dosimetrically to that of Monte Carlo (MC) for thoracic spinal lesions. Our institutional CK-based SBRT database for thoracic spinal lesions was queried and a cohort was generated. Patients were planned using RyTc and MC algorithms using the same beam angles and monitor units. Dose-volume histograms of the planning target volume (PTV), spinal cord, esophagus, and skin were generated, and dosimetric parameters were compared. There were 37 patients in the cohort. The average percentage volume of PTV covered by the prescribed dose with RyTc and MC algorithms was 91.1% and 80.4%, respectively (P < .001). The difference in average maximum spinal cord dose between RyTc and MC plans was significant (1126 vs 1084 cGy, P = .004), with the MC dose ranging from 18.7% below to 13.8% above the corresponding RyTc dose. A small reduction in maximum skin dose was also noted (P = .017), although no difference was seen in maximum esophageal dose (P = .15). Only PTVs smaller than 27 cm(3) were found to correlate with large (>10%) changes in dose to 90% of the volume (P = .014), while no correlates with the average percentage volume of PTV covered by the prescribed dose were demonstrated. For thoracic spinal CK-based SBRT, RyTc computation may overestimate the MC calculated average percentage volume of PTV covered by the prescribed dose and have unpredictable effects on doses to organs at risk, particularly the spinal cord. In this setting, use of RyTc optimization should be limited and always verified with MC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/secundário , Fracionamento da Dose de Radiação , Tomografia Computadorizada Quadridimensional , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Método de Monte Carlo , Neoplasias da Coluna Vertebral/secundário , Resultado do Tratamento , Adulto Jovem
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