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2.
Health Promot Pract ; : 15248399241234058, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415651

RESUMO

Anti-Asian and anti-immigrant sentiment has surged in the country in the last 3 years. Food insecurity is also on the rise; in our local needs assessment of n = 1,270 Asian American adults in New York City, accessing food was cited as the number 1 priority among those who needed help. Finally, racial discrimination and food access are related to fear of being attacked-driving feelings of safety and therefore willingness to travel for food. To combat these narratives and leveraging pivots by our community partners, we implemented a community-supported agriculture pilot program (n = 38) to assess whether culturally appropriate food access can improve diet and foster cross-cultural learning among immigrant families in Brooklyn, NY. Over a 20-week period from June to October 2022, participants received Chinese-specific produce and nutrition education. Participants reported eating more and a greater variety of vegetables and had higher vegetable intake measured via skin carotenoid scores. This pilot may inform the adaptation of nutrition interventions to reduce inequities in chronic diseases in immigrant communities.

3.
Biotechnol J ; 19(1): e2300359, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37986209

RESUMO

Physical networks are ubiquitous in nature, but many of them possess a complex organizational structure that is difficult to recapitulate in artificial systems. This is especially the case in biomedical and tissue engineering, where the microstructural details of 3D cell scaffolds are important. Studies of biological networks-such as fibroblastic reticular cell (FRC) networks-have revealed the crucial role of network topology in a range of biological functions. However, cell scaffolds are rarely analyzed, or designed, using graph theory. To understand how networks affect adhered cells, 3D culture platforms capturing the complex topological properties of biologically relevant networks would be needed. In this work, we took inspiration from the small-world organization (high clustering and low path length) of FRC networks to design cell scaffolds. An algorithmic toolset was created to generate the networks and process them to improve their 3D printability. We employed tools from graph theory to show that the networks were small-world (omega factor, ω = -0.10 ± 0.02; small-world propensity, SWP = 0.74 ± 0.01). 3D microprinting was employed to physicalize networks as scaffolds, which supported the survival of FRCs. This work, therefore, represents a bioinspired, graph theory-driven approach to control the networks of microscale cell niches.


Assuntos
Linfonodos , Alicerces Teciduais
4.
Nat Commun ; 14(1): 7493, 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980430

RESUMO

Strong circularly polarized excitation opens up the possibility to generate and control effective magnetic fields in solid state systems, e.g., via the optical inverse Faraday effect or the phonon inverse Faraday effect. While these effects rely on material properties that can be tailored only to a limited degree, plasmonic resonances can be fully controlled by choosing proper dimensions and carrier concentrations. Plasmon resonances provide new degrees of freedom that can be used to tune or enhance the light-induced magnetic field in engineered metamaterials. Here we employ graphene disks to demonstrate light-induced transient magnetic fields from a plasmonic circular current with extremely high efficiency. The effective magnetic field at the plasmon resonance frequency of the graphene disks (3.5 THz) is evidenced by a strong ( ~ 1°) ultrafast Faraday rotation ( ~ 20 ps). In accordance with reference measurements and simulations, we estimated the strength of the induced magnetic field to be on the order of 0.7 T under a moderate pump fluence of about 440 nJ cm-2.

6.
Cancer Causes Control ; 34(12): 1043-1058, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37481755

RESUMO

PURPOSE: To apply principles of group model building (GMB), a participatory systems science approach, to identify barriers and opportunities for collective impact around nutrition programming to reduce cancer risk for immigrant communities in an urban environment. METHODS: We convened four in-person workshops applying GMB with nine community partners to generate causal loop diagrams (CLDs)-a visual representation of hypothesized causal relationships between variables and feedback structures within a system. GMB workshops prompted participants to collaboratively identify programmatic goals and challenges related to (1) community gardening, (2) nutrition education, (3) food assistance programs, and (4) community-supported agriculture. Participants then attended a plenary session to integrate findings from all workshops and identify cross-cutting ideas for collective action. RESULTS: Several multilevel barriers to nutrition programming emerged: (1) food policies center the diets and practices of White Americans and inhibit culturally tailored food guidelines and funding for culturally appropriate nutrition education; (2) the lack of culturally tailored nutrition education in communities is a missed opportunity for fostering pride in immigrant food culture and sustainment of traditional food practices; and (3) the limited availability of traditional ethnic produce in food assistance programs serving historically marginalized immigrant communities increases food waste and worsens food insecurity. CONCLUSION: Emergent themes coalesced around the need to embed cultural tailoring into all levels of the food system, while also considering other characteristics of communities being reached (e.g., language needs). These efforts require coordinated actions related to food policy and advocacy, to better institutionalize these practices within the nutrition space.


Assuntos
Alimentos , Eliminação de Resíduos , Humanos , Estado Nutricional , Dieta , Política Nutricional
7.
Epidemiol Rev ; 45(1): 127-139, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37045807

RESUMO

Improving race and ethnicity (hereafter, race/ethnicity) data quality is imperative to ensure underserved populations are represented in data sets used to identify health disparities and inform health care policy. We performed a scoping review of methods that retrospectively improve race/ethnicity classification in secondary data sets. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, searches were conducted in the MEDLINE, Embase, and Web of Science Core Collection databases in July 2022. A total of 2 441 abstracts were dually screened, 453 full-text articles were reviewed, and 120 articles were included. Study characteristics were extracted and described in a narrative analysis. Six main method types for improving race/ethnicity data were identified: expert review (n = 9; 8%), name lists (n = 27, 23%), name algorithms (n = 55, 46%), machine learning (n = 14, 12%), data linkage (n = 9, 8%), and other (n = 6, 5%). The main racial/ethnic groups targeted for classification were Asian (n = 56, 47%) and White (n = 51, 43%). Some form of validation evaluation was included in 86 articles (72%). We discuss the strengths and limitations of different method types and potential harms of identified methods. Innovative methods are needed to better identify racial/ethnic subgroups and further validation studies. Accurately collecting and reporting disaggregated data by race/ethnicity are critical to address the systematic missingness of relevant demographic data that can erroneously guide policymaking and hinder the effectiveness of health care practices and intervention.


Assuntos
Confiabilidade dos Dados , Etnicidade , Grupos Raciais , Humanos , Área Carente de Assistência Médica , Estudos Retrospectivos
8.
PLoS One ; 17(6): e0270667, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35763531

RESUMO

Scene perception involves extracting the identities of the objects comprising a scene in conjunction with their configuration (the spatial layout of the objects in the scene). How object identity and configuration information is weighted during scene processing and how this weighting evolves over the course of scene processing however, is not fully understood. Recent developments in convolutional neural networks (CNNs) have demonstrated their aptitude at scene processing tasks and identified correlations between processing in CNNs and in the human brain. Here we examined four CNN architectures (Alexnet, Resnet18, Resnet50, Densenet161) and their sensitivity to changes in object and configuration information over the course of scene processing. Despite differences among the four CNN architectures, across all CNNs, we observed a common pattern in the CNN's response to object identity and configuration changes. Each CNN demonstrated greater sensitivity to configuration changes in early stages of processing and stronger sensitivity to object identity changes in later stages. This pattern persists regardless of the spatial structure present in the image background, the accuracy of the CNN in classifying the scene, and even the task used to train the CNN. Importantly, CNNs' sensitivity to a configuration change is not the same as their sensitivity to any type of position change, such as that induced by a uniform translation of the objects without a configuration change. These results provide one of the first documentations of how object identity and configuration information are weighted in CNNs during scene processing.


Assuntos
Encéfalo , Redes Neurais de Computação , Cabeça , Humanos
9.
J Orthop ; 30: 72-76, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241892

RESUMO

STUDY DESIGN: Retrospective Case Series. OBJECTIVES: Minimally invasive techniques have emerged as a useful tool in the treatment of neoplastic spine pathology due to decrease in surgical morbidity and earlier adjuvant treatment. The objective of this study was to analyze outcomes and complications in a cohort of unstable, symptomatic pathologic fractures treated with percutaneous pedicle screw fixation (PPSF). METHODS: A retrospective review was performed on consecutive patients with spinal stabilization for unstable pathologic neoplastic fractures between 2007 and 2017. Patients who underwent PPSF through a minimally invasive approach were included. Surgical indications included intractable pain, mechanical instability, and neurologic compromise with radiologic visualization of the lesion. RESULTS: 20 patients with mean Tomita Score of 6.3 ± 2.1 points [95% CI, 5.3-7.2] were treated with constructs that spanned a mean of 4.7 ± 1.4 [95% CI, 4.0-5.3] instrumented levels. 10 (50%) patients were augmented with vertebroplasty. Majority of patients (65%) had no complications during their hospital stay and were discharged home (60%). Four patients received reoperation: two extracavitary corpectomies, one pathologic fracture at a different level, and one adjacent segment disease. CONCLUSION: Minimally invasive PPSF is a safe and effective option when treating unstable neoplastic fractures and may be a viable alternative to the traditional open approach in select cases. LEVEL OF EVIDENCE: 4.

10.
Kidney Med ; 3(6): 1095-1098, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34939020

RESUMO

Infiltration of a surgically placed hemodialysis vascular access is recognized as a major contributor to the high health care costs associated with dialysis-dependent patients. Three-dimensional (3D) modeling is a critical tool for proceduralists in preparation for surgical interventions. No such modeling is currently available for dialysis specialists to avoid the common complication of vascular access infiltration. Ferumoxytol-enhanced magnetic resonance angiography was used to generate 3D image data that could render a 3D resin-based model of a vascular access without exposing the patient to iodinated or gadolinium-based radiologic contrast. The technique required an abbreviated magnetic resonance angiography procedure interfaced with a 3D printer workstation. An interventional radiology suite was not required. In the described case, the brachial artery was clearly delineated from a cephalic vein to basilic vein bypass with a 3D spatial resolution of 1 mm. In conclusion, we demonstrate that this new technology pathway can provide preprocedural guidance that has the potential to significantly reduce the morbidity and cost associated with vascular access infiltration.

11.
Endosc Int Open ; 9(12): E1870-E1876, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34917455

RESUMO

Background and study aims A novel technique for Barrett's esophagus (BE) ablation, termed hybrid APC, has recently been developed. The aims of this US pilot study were to evaluate the efficacy, tolerance and safety of hybrid APC for the treatment of BE. Patients and methods Patients with biopsy-proven BE referred to our tertiary care center over a 12-month period for mucosal ablation were eligible for this study. Efficacy of ablation was measured on follow-up endoscopy by demonstrating either a reduction of visible BE or biopsies proving complete resolution of intestinal metaplasia (CRIM). To evaluate tolerance and safety, patients were called on post-procedure days 1 and 7. Results Twenty-two patients with BE (4.5 % intramucosal carcinoma, 31.8 % high-grade dysplasia, 18.1 % low-grade dysplasia, 36.3 % non-dysplastic, 9.1 % indefinite for dysplasia) underwent 40 treatments with hybrid APC. All patients had endoscopic improvement of BE disease and 19 of 22 patients (86.4 %) achieved CRIM. With regard to tolerance, average pain scores (0 to 10 scale) on follow-up were 2.65 and 0.62 on days 1 and 7, respectively. With regards to safety, there were two treatment-related strictures (9.1 %) that required a single balloon dilation. Conclusions Hybrid APC appears to be promising in the treatment of BE. The ablation protocol used in this study demonstrated efficacy, tolerability, and a safety profile similar to radiofrequency ablation. Given the significant price difference between hybrid APC and other modalities for Barrett's ablation, this modality may be more cost-effective. These results warrant further study in a large prospective multicenter trial.

13.
Nat Commun ; 12(1): 5710, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588444

RESUMO

Neuromorphic hardware implementation of Boltzmann Machine using a network of stochastic neurons can allow non-deterministic polynomial-time (NP) hard combinatorial optimization problems to be efficiently solved. Efficient implementation of such Boltzmann Machine with simulated annealing desires the statistical parameters of the stochastic neurons to be dynamically tunable, however, there has been limited research on stochastic semiconductor devices with controllable statistical distributions. Here, we demonstrate a reconfigurable tin oxide (SnOx)/molybdenum disulfide (MoS2) heterogeneous memristive device that can realize tunable stochastic dynamics in its output sampling characteristics. The device can sample exponential-class sigmoidal distributions analogous to the Fermi-Dirac distribution of physical systems with quantitatively defined tunable "temperature" effect. A BM composed of these tunable stochastic neuron devices, which can enable simulated annealing with designed "cooling" strategies, is conducted to solve the MAX-SAT, a representative in NP-hard combinatorial optimization problems. Quantitative insights into the effect of different "cooling" strategies on improving the BM optimization process efficiency are also provided.

14.
Prev Med Rep ; 24: 101519, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34540571

RESUMO

There is a lack of quantitative research examining how the pandemic has affected individuals at different income levels. The Asian American population has the highest level of income inequality and serves as an excellent case study for examining differences in experience between income groups. A non-probability sample of 3084 Asian American adults living in the US was surveyed in June 2020, examining health-related behaviors and outcomes. Descriptive analyses and chi-squared statistics were conducted to identify differences in income groups (low, medium, high) among Asian Americans across regional subgroups (East, South, Southeast, Multiethnic) and disaggregated ethnicities (Chinese, Asian Indian, Japanese, and Filipino). In bivariable analyses, a significantly (p < 0.05) greater percentage of high-income individuals during the pandemic reported having enough money to buy the food they needed, a away to get to the store for food, and reported stores where they get food had everything they needed. High-income Chinese, Japanese, and Filipino individual also noted that, since the COVID-19 crisis, they are now working partially or fully from home. In the total sample, multivariable adjusted logistic regressions revealed medium- and low-income individuals to have low odds of working partially or fully from home (AOR:0.55, 95%CI:0.42-0.72), higher odds of not having enough money to buy the food they needed (AOR:3.54, 95%CI:1.43-11.81), and higher odds of eating less (AOR:1.58, 95%CI:1.14-2.22). These results highlight the importance of considering income distribution when characterizing disparities in health behaviors within racial/ethnic minority groups and underscore the need to bolster the infrastructure supporting low-income Asian Americans.

15.
Sci Rep ; 11(1): 13019, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155284

RESUMO

Semaphorin3A is considered a classical repellent molecule for developing neurons and a potent inhibitor of regeneration after nervous system trauma. Vinaxanthone and other Sema3A inhibitors are currently being tested as possible therapeutics to promote nervous system regeneration from injury. Our previous study on Sema3A demonstrated a switch in Sema3A's function toward induction of nerve regeneration in adult murine corneas and in culture of adult peripheral neurons. The aim of the current study is to determine the direct effects of Vinaxanthone on the Sema3A induced adult neuronal growth. We first demonstrate that Vinaxanthone maintains its anti-Sema3A activity in embryonic dorsal root ganglia neurons by inhibiting Sema3A-induced growth cone collapse. However, at concentrations approximating its IC50 Vinaxanthone treatment does not significantly inhibit neurite formation of adult peripheral neurons induced by Sema3A treatment. Furthermore, Vinaxanthone has off target effects when used at concentrations above its IC50, and inhibits neurite growth of adult neurons treated with either Sema3A or NGF. Our results suggest that Vinaxanthone's pro-regenerative effects seen in multiple in vivo models of neuronal injury in adult animals need further investigation due to the pleiotropic effect of Sema3A on various non-neuronal cell types and the possible effect of Vinaxanthone on other neuroregenerative signals.


Assuntos
Cones de Crescimento/efeitos dos fármacos , Cones de Crescimento/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Semaforina-3A/metabolismo , Xantonas/farmacologia , Animais , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Camundongos , Neurogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Nervo Trigêmeo/efeitos dos fármacos , Nervo Trigêmeo/metabolismo
16.
J Homosex ; 68(8): 1371-1392, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31833818

RESUMO

This ethnographic study considers the political economy of queer and trans of color community organizations in the context of urban neoliberal governance in Toronto, Canada. While state institutions promote entrepreneurship-based arts funding as a means of economic development, queer and trans of color grassroots initiatives engage with these institutions in ways that compel a reconsideration of the relationship between entrepreneurship and neoliberalism. I propose the concept sacrificial entrepreneurship to identify how the disruption of the neoliberal incitement to personal gain by sacrificing one's economic well-being is patterned along lines of race, gender and sexuality. Focusing on Unapologetic Burlesque, a queer anti-racist community performance initiative, I show how queer and trans of color grassroots initiatives in Toronto take public resources intended to promote individual profit-making to create minoritized spaces of belonging. Through sacrificial entrepreneurship queer and trans of color subjects simultaneously collude and oppose the unfolding of neoliberal state initiatives.


Assuntos
Arte , Empreendedorismo , Política , Minorias Sexuais e de Gênero , Canadá , Financiamento de Capital , Feminino , Humanos , Grupos Raciais , Trabalho
17.
J Hand Surg Am ; 46(2): 106-113, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32950317

RESUMO

PURPOSE: This study examined the effect of low-profile volar rim plates (VR), proximally placed standard variable-angle locking plates (pVA-LCP), and distally placed standard variable-angle locking plates (dVA-LCP) on the flexor pollicis longus (FPL) tendon in a cadaver model. We hypothesized that tendons from the VR and pVA-LCP groups would exhibit similar contact pressures, wear patterns, and post-fatigue testing mechanical properties, whereas dVA-LCP tendons would exhibit higher contact pressures, increased tendon wear patterns, and decreased mechanical properties. METHODS: Nine matched pairs of cadaveric specimens were used in this study. Thin-film pressure sensors were used to measure the initial contact loads between plates and FPL tendons. Specimens were cyclically loaded for 10,000 cycles by actuating the FPL tendon. Cycled tendons were harvested, photographed with a stereomicroscope, and graded for wear on a Likert scale by 5 observers who were blinded to the study protocol. Uniaxial tensile testing measured mechanical properties of the tendon: ultimate failure load, ultimate stress, percent stress relaxation, elastic modulus, and stiffness. RESULTS: With regard to the cadaveric FPL tendon, VR and dVA-LCP had increased contact pressure and tendon wear compared with pVA-LCP. There were no significant differences in contact pressure or tendon wear between dVA-LCP and VR. There was no major difference in the tested mechanical properties of the FPL tendon among any of the groups. CONCLUSIONS: Plates placed directly on or beyond the volar rim demonstrate increased contact pressures and increased tendon wear in a cadaveric model. CLINICAL RELEVANCE: Although low-profile plates allow for fixation of smaller volar fragments in the distal radius, they cause substantial contact with the FPL tendon, which may rupture if the plate is not removed.


Assuntos
Fraturas do Rádio , Traumatismos dos Tendões , Placas Ósseas , Cadáver , Fixação Interna de Fraturas , Humanos , Traumatismos dos Tendões/cirurgia , Tendões/cirurgia
18.
ACS Appl Mater Interfaces ; 12(42): 47355-47367, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33027591

RESUMO

The recent rise of adoptive T cell therapy (ATCT) as a promising cancer immunotherapy has triggered increased interest in therapeutic T cell bioprocessing. T cell activation is a critical processing step and is known to be modulated by physical parameters, such as substrate stiffness. Nevertheless, relatively little is known about how biophysical factors regulate immune cells, such as T cells. Understanding how T cell activation is modulated by physical and biochemical cues may offer novel methods to control cell behavior for therapeutic cell processing. Inspired by T cell mechanosensitivity, we developed a multiwell, reusable, customizable, two-dimensional (2D) polyacrylamide (PA) hydrogel-integrated culture device to study the physicochemical stimulation of Jurkat T cells. Substrate stiffness and ligand density were tuned by concentrations of the hydrogel cross-linker and antibody in the coating solution, respectively. We cultured Jurkat T cells on 2D hydrogels of different stiffnesses that presented surface-immobilized stimulatory antibodies against CD3 and CD28 and demonstrated that Jurkat T cells stimulated by stiff hydrogels (50.6 ± 15.1 kPa) exhibited significantly higher interleukin-2 (IL-2) secretion, but lower proliferation, than those stimulated by softer hydrogels (7.1 ± 0.4 kPa). In addition, we found that increasing anti-CD3 concentration from 10 to 30 µg/mL led to a significant increase in IL-2 secretion from cells stimulated on 7.1 ± 0.4 and 9.3 ± 2.4 kPa gels. Simultaneous tuning of substrate stiffness and stimulatory ligand density showed that the two parameters synergize (two-way ANOVA interaction effect: p < 0.001) to enhance IL-2 secretion. Our results demonstrate the importance of physical parameters in immune cell stimulation and highlight the potential of designing future immunostimulatory biomaterials that are mechanically tailored to balance stimulatory strength and downstream proliferative capacity of therapeutic T cells.


Assuntos
Resinas Acrílicas/química , Técnicas de Cultura de Células , Hidrogéis/química , Linfócitos T/imunologia , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , Humanos , Células Jurkat , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície
19.
Neuron ; 108(1): 209-224.e6, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32827456

RESUMO

The representation of odor in olfactory cortex (piriform) is distributive and unstructured and can only be afforded behavioral significance upon learning. We performed 2-photon imaging to examine the representation of odors in piriform and in two downstream areas, the orbitofrontal cortex (OFC) and the medial prefrontal cortex (mPFC), as mice learned olfactory associations. In piriform, we observed that odor responses were largely unchanged during learning. In OFC, 30% of the neurons acquired robust responses to conditioned stimuli (CS+) after learning, and these responses were gated by internal state and task context. Moreover, direct projections from piriform to OFC can be entrained to elicit learned olfactory behavior. CS+ responses in OFC diminished with continued training, whereas persistent representations of both CS+ and CS- odors emerged in mPFC. Optogenetic silencing indicates that these two brain structures function sequentially to consolidate the learning of appetitive associations.


Assuntos
Comportamento Apetitivo/fisiologia , Aprendizagem por Associação/fisiologia , Neurônios/fisiologia , Odorantes , Condutos Olfatórios/fisiologia , Córtex Piriforme/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Condicionamento Clássico/fisiologia , Microscopia Intravital , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica , Optogenética , Córtex Piriforme/citologia , Córtex Pré-Frontal/citologia
20.
Trends Biotechnol ; 38(10): 1054-1065, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32466966

RESUMO

The meteoric rise of cancer immunotherapy in the past decade has led to promising treatments for a number of hard-to-treat malignancies. In particular, adoptive T cell therapy has recently reached a major milestone with two products approved by the US FDA. However, the inherent complexity of cell-based immunotherapies means that their manufacturing time, cost, and controllability limit their effectiveness and geographic reach. One way to address these issues may lie in complementing the dominant, reductionistic mentality in modern medicine with complex systems thinking. In this opinion article, we identify key concepts from complexity theory to address manufacturing challenges in cell-based immunotherapies and raise the possibility of a unifying framework upon which future bioprocessing strategies may be designed.


Assuntos
Bioengenharia , Imunoterapia , Neoplasias/terapia , Antineoplásicos , Humanos
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