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1.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34725153

RESUMO

In nine studies using archival data, surveys, and experiments, we identify a factor that predicts gender differences in time stress and burnout. Across academic and professional settings, women are less likely to ask for more time when working under adjustable deadlines (studies 1 to 4a). Women's discomfort in asking for more time on adjustable deadlines uniquely predicts time stress and burnout, controlling for marital status, industry, tenure, and delegation preferences (study 1). Women are less likely to ask for more time to complete their tasks because they hold stronger beliefs that they will be penalized for these requests and worry more about burdening others (studies 1 to 2d). We find no evidence that women are judged more harshly than men (study 3). We also document a simple organizational intervention: formal processes for requesting deadline extensions reduce gender differences in asking for more time (studies 4a to 5).


Assuntos
Caracteres Sexuais , Estresse Psicológico , Mulheres/psicologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
2.
J Drugs Dermatol ; 22(11): e9-e11, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943268

RESUMO

BACKGROUND: Oral tetracyclines (TCNs) are commonly prescribed for acne, but they have been shown to increase the risk of hyperpigmentation, particularly in the setting of sun exposure. OBJECTIVE: We evaluated seasonal trends in TCN-associated hyperpigmentation incidence in addition to Google search trends for hyperpigmentation-related terms. METHODS: We performed a retrospective review of acne patients seen at Massachusetts General Brigham and Women’s Hospital between 1992 and 2022. We calculated the incidence of new hyperpigmentation diagnoses for each drug cohort. We also analyzed search volume of hyperpigmentation-related terms extracted from Google Trends. RESULTS: Seasonal differences in new hyperpigmentation diagnoses were identified among acne patients prescribed doxycycline (P=0.016), with peak incidence in April. In the control group of patients who had never received a TCN, diagnoses peaked in May. There were no significant seasonal differences among patients prescribed minocycline (P=0.885). There was greater search volume for hyperpigmentation-related terms in spring and summer compared to fall and winter (P<0.001). Limitations of this study include its retrospective nature and reliance on prescription and diagnosis coding data. CONCLUSIONS: Our findings support the seasonal periodicity of acne-related hyperpigmentation, underscoring the importance of photoprotection counseling for patients with acne. Additionally, doxycycline may be associated with an earlier onset of hyperpigmentation, suggesting a potential benefit of considering minocycline or other alternatives to doxycycline. J Drugs Dermatol. 2023;22(11):e9-e11    doi:10.36849/JDD.7409e.


Assuntos
Acne Vulgar , Hiperpigmentação , Humanos , Feminino , Estações do Ano , Doxiciclina/efeitos adversos , Minociclina , Estudos Retrospectivos , Tetraciclina , Antibacterianos/efeitos adversos , Acne Vulgar/tratamento farmacológico , Acne Vulgar/epidemiologia , Hiperpigmentação/induzido quimicamente , Hiperpigmentação/diagnóstico , Hiperpigmentação/epidemiologia
3.
Phytochem Anal ; 34(1): 48-55, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36191930

RESUMO

INTRODUCTION: Data Fusion-based Discovery (DAFdiscovery) is a pipeline designed to help users combine mass spectrometry (MS), nuclear magnetic resonance (NMR), and bioactivity data in a notebook-based application to accelerate annotation and discovery of bioactive compounds. It applies Statistical Total Correlation Spectroscopy (STOCSY) and Statistical HeteroSpectroscopy (SHY) calculation in their data using an easy-to-follow Jupyter Notebook. METHOD: Different case studies are presented for benchmarking, and the resultant outputs are shown to aid natural products identification and discovery. The goal is to encourage users to acquire MS and NMR data from their samples (in replicated samples and fractions when available) and to explore their variance to highlight MS features, NMR peaks, and bioactivity that might be correlated to accelerated bioactive compound discovery or for annotation-identification studies. RESULTS: Different applications were demonstrated using data from different research groups, and it was shown that DAFdiscovery reproduced their findings using a more straightforward method. CONCLUSION: DAFdiscovery has proven to be a simple-to-use method for different situations where data from different sources are required to be analyzed together.


Assuntos
Produtos Biológicos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos
4.
Support Care Cancer ; 30(10): 7827-7831, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35804176

RESUMO

PURPOSE: Supportive oncodermatology has been shown to improve several aspects of care for patients with cancer, but research showing improved diagnostic accuracy as a benefit of supportive oncodermatology is largely lacking. We thus aimed to evaluate different dermatologist groups' diagnostic accuracy for heterogenous cutaneous toxicities, using cutaneous immune-related adverse events (cirAEs) from immune checkpoint inhibitors (ICIs) as a test model. METHODS: Billing/requisition codes were used to identify patients who initiated programmed death-1/ligand-1 (PD-1/PD-L1) ICIs between 2010 and 2019 at Dana-Farber Cancer Institute/Brigham and Women's Hospital/Massachusetts General Hospital and underwent a subsequent skin biopsy. For each biopsied cirAE, pre-biopsy clinical diagnoses and post-biopsy clinico-pathologic diagnoses were retrospectively obtained from the medical record. Each biopsy-ordering dermatology provider was categorized as a general dermatologist or supportive oncodermatologist on the basis of providing clinical care within a cancer-center or attending on a hospital/clinic service dedicated to anti-cancer drug-related skin toxicities. RESULTS: Of 4,183 patients who initiated anti-PD-1/PD-L1 therapy between 2010 and 2019, 101 (2.4%) patients collectively had 104 biopsied cirAEs. In more than one-third of all reviewed biopsied cirAEs (n = 39, 37.5%), histopathology results frequently led to revision of the pre-biopsy clinical diagnosis. The rate of initial cirAE misclassification amongst supportive oncodermatologists was significantly lower than that amongst general dermatologists (18/66, 27.3% vs. 21/38, 55.3%; Fischer's-exact-test p = 0.006). CONCLUSION: Experienced supportive oncodermatologists may benefit patient care through increased diagnostic accuracy for skin toxicities from ICIs. Collectively, these results underscore that both skin biopsy from any dermatology provider and oncodermatology referral (where available) are valuable resources that should be integrated into supportive cancer care.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias , Dermatopatias , Antígeno B7-H1 , Biópsia , Dermatologistas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Feminino , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Ligantes , Neoplasias/tratamento farmacológico , Estudos Retrospectivos
5.
BMC Med Educ ; 22(1): 423, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655160

RESUMO

PURPOSE: The disruption of undergraduate medical education (UME) by the COVID-19 pandemic has sparked rapid, real-time adjustments by medical educators and students. While much is known about online teaching in general, little guidance is available to medical educators on how to adapt courses not originally designed for the online environment. To guide our faculty in this transition we conducted a needs assessment of students enrolled in virtual courses across all 4 years of UME training. METHODS: Using a mixed-methods approach, we conducted a single-institution virtual learning needs assessment in May and June of 2020. We developed and disseminated a survey to assess student experiences with virtual learning. We conducted quantitative and qualitative analysis of responses (n = 255 or 39%) to identify emergent themes. RESULTS: We identified six interdependent themes that need to be met for medical students to fully reach their learning potential: access to stable internet and quiet study spaces, flexible course design with asynchronous, self-paced components, clear expectations for engagement with content and each other, a sense of connectedness with faculty and peers, synchronous classes that maximize interactivity, and assessments that foster a sense of learning over performance. Interpersonal relationships with faculty and peers affected students' sense of learning more than any other factor. CONCLUSIONS: Based on our findings we propose a hierarchy of needs for virtual learning that provides guidance on adapting existing medical school courses to the remote setting and overcoming common challenges. We highlight opportunities for how virtual elements may enrich in-person courses going forward, including in the clinical setting. Although the solutions required to meet the threshold of need at each level may differ based on the context, attending to these same fundamental needs can be extrapolated and applied to learners across a range of environments beyond the virtual.


Assuntos
COVID-19 , Educação de Graduação em Medicina , Estudantes de Medicina , COVID-19/epidemiologia , Humanos , Pandemias , Inquéritos e Questionários
6.
Compos B Eng ; 242: 110060, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35754456

RESUMO

The transmission of the SARS-CoV-2 coronavirus has been shown through droplets generated by infected people when coughing, sneezing, or talking in close contact. These droplets either reach the next person directly or land on nearby surfaces. The objective of this study is to develop a novel, durable, and effective disinfecting antimicrobial (antiviral, antibacterial, and antifungal) styrene-ethylene/butylene-styrene (SEBS) based thermoplastic elastomers (TPE). TPE incorporated with six different formulations was investigated for mechanical and antiviral performance. The formulations consist of a combination of zinc pyrithione (ZnPT), sodium pentaborate pentahydrate (NaB), disodium octaborate tetrahydrate (DOT), and chlorhexidine (CHX). ZnPT and DOT incorporated TPE showed a reduction of microbes such as bacteria by up to 99.99%, deactivated Adenovirus, Poliovirus, Norovirus, and reduced a strain of the coronavirus family by 99.95% in 60 min on TPE samples. Control samples had higher tensile strengths among all formulations and tensile strength decreased by around 14%, 21% and 27% for ZnPT and DOT combinations compared to control samples. The elongation at break decreased by around 7%, 9% and 12% with ZnPT and DOT combinations, where it reached minimum values of 720%, 702% and 684%, respectively. The 100% Modulus and 300% Modulus slightly increased with ZnPT and NaB combination (reaching values from 1.6 to 1.9 MPa and 2.6-2.9 MPa respectively) in comparison with control samples. The MFI also decreased with antimicrobial and antiviral additives (decreasing values from 64.8 to 43.3 g/10 min). ZnPT and NaB combination showed the lowest MFI (43.3 g/10 min) and reduced the MFI of control sample by around 33%. TPE samples containing ZnPT and DOT combination showed biocidal activity against the microorganisms tested and can be used to develop antimicrobial products for multiple touchpoints within a vehicle and micro-mobility.

12.
Small ; 11(45): 6051-7, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26449185

RESUMO

The fabrication and properties of pH-responsive colloidal particles are reported, which change shape rapidly (less than 200 ms), nearly independent of the diffusion of the pH altering species that trigger their actuation, and far more rapid than their Brownian motion. These particles are mechanically bistable, as revealed by their hysteretic shape response. Finite element analysis (FEA) shows that mechanical hysteresis and bistability derives from the colloids' spherical curvature. Mechanical characterization of the bilayered polymers comprising the colloidal particles shows that viscoelastic relaxation plays a non-negligible role in limiting the shape switching rate; however, energy landscapes obtained from FEA simulations suggest that by tuning the elastic moduli and thicknesses of the constituent polymer layers, microparticles of the size shown here may be fabricated to actuate on timescales as fast as 1 µs.

13.
Proc Natl Acad Sci U S A ; 109(40): 16057-62, 2012 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-22992652

RESUMO

Nature's particles, such as spores, viruses or cells, are adaptive--i.e., they can rapidly alter major phenomenological attributes such as shape, size, or curvature in response to environmental changes. Prominent examples include the hydration-mediated opening of ice plant seeds, actuation of pine cones, or the ingenious snapping mechanism of predatory Venus flytraps that rely on concave-to-convex reconfigurations. In contrast, experimental realization of reconfigurable synthetic microparticles has been extremely challenging and only very few examples have been reported so far. Here, we demonstrate a generic approach towards dynamically reconfigurable microparticles that explores unique anisotropic particle architectures, rather than direct synthesis of sophisticated materials such as shape-memory polymers. Solely enabled by their architecture, multicompartmental microcylinders made of conventional polymers underwent active reconfiguration including shape-shifting, reversible switching, or three-way toggling. Once microcylinders with appropriate multicompartmental architectures were prepared by electrohydrodynamic cojetting, simple exposure to an external stimulus, such as ultrasound or an appropriate solvent, gives rise to interfacial stresses that ultimately cause reversible topographical reconfiguration. The broad versatility of the electrohydrodynamic cojetting process with respect to materials selection and processing suggests strategies for a wide range of dynamically reconfigurable adaptive materials including those with prospective applications for sensors, reprogrammable microactuators, or targeted drug delivery.


Assuntos
Engenharia Biomédica/métodos , Materiais Biomiméticos , Sistemas de Liberação de Medicamentos/métodos , Microesferas , Polímeros/química , Anisotropia , Engenharia Biomédica/tendências , Hidrodinâmica , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura , Polímeros/síntese química
14.
Angew Chem Int Ed Engl ; 53(9): 2332-8, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24574030

RESUMO

Compared to two-dimensional substrates, only a few methodologies exist for the spatially controlled decoration of three-dimensional objects, such as microparticles. Combining electrohydrodynamic co-jetting with synthetic polymer chemistry, we were able to create two- and three-patch microparticles displaying chemically orthogonal anchor groups on three distinct surface patches of the same particle. This approach takes advantage of a combination of novel chemically orthogonal polylactide-based polymers and their processing by electrohydrodynamic co-jetting to yield unprecedented multifunctional microparticles. Several micropatterned particles were fabricated displaying orthogonal click functionalities. Specifically, we demonstrate novel two- and three-patch particles. Multi-patch particles are highly sought after for their potential to present multiple distinct ligands in a directional manner. This work clearly establishes a viable route towards orthogonal reaction strategies on multivalent micropatterned particles.


Assuntos
Poliésteres/química , Química Click/métodos , Microesferas , Tamanho da Partícula , Propriedades de Superfície
15.
Sci Total Environ ; 931: 172689, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38692315

RESUMO

Cyanobacterial Harmful Algal Blooms (CyanoHABs) pose a significant threat to communities globally, impacting ecosystems and public health. This study provides an in-depth review of the current state of cyanotoxins and the distribution of CyanoHABs species in Brazil, while also detailing the methods used for their detection. Four hundred and twenty-one incidents were analyzed from 1993 to 2021, compiling cyanotoxin records and toxic CyanoHABs occurrences. The investigation begins with the first detection of microcystins in 1994 and highlights pivotal moments, like the 1996 "Caruaru Syndrome" outbreak. This event encouraged research and updated cyanotoxin-monitoring guidelines. The Brazilian drought period of 2015-2016 exacerbated cyanobacterial growth and saxitoxin levels, coinciding with Zika-related microcephaly. This study delves into methods used for cyanotoxin analysis, including ELISA, bioassays, HPLC, and LC-MS. Additionally, we investigated the toxicity of 37 cyanobacterial strains isolated from various Brazilian environments. Extracts were tested against Artemia salina and analyzed by LC-MS. Results revealed toxicity in extracts from 49 % of cyanobacterial strains. LC-MS results were analyzed using GNPS MS/MS molecular networking for comparing experimental spectra with those of cyanotoxin standards against in-house databases and the existing literature. Our research underscores the variability in cyanotoxin production among species and over time, extending beyond microcystins. LC-MS results, interpreted through the GNPS platform, revealed six cyanotoxin groups in Brazilian strains. Yet, compounds present in 75 % of the toxic extracts remained unidentified. Further research is crucial for fully comprehending the impact of potentially harmful organisms on water quality and public health management strategies. The study highlights the urgent need for continuously monitoring cyanobacteria and the cyanotoxin inclusion of management in public health policies.


Assuntos
Cianobactérias , Monitoramento Ambiental , Proliferação Nociva de Algas , Microcistinas , Brasil/epidemiologia , Monitoramento Ambiental/métodos , Microcistinas/análise , Toxinas Bacterianas/análise , Toxinas Marinhas/análise
16.
Langmuir ; 29(20): 6181-6, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23617390

RESUMO

Janus microcylinders composed of different polymers were prepared through coaxial co-jetting with dual-core flows, followed by cross-linking, microsectioning, and shell removal. Uniquely shaped building blocks can be fabricated by photo-patterning of one hemisphere of the microcylinders.


Assuntos
Técnicas Analíticas Microfluídicas , Poliglactina 910/química , Hidrodinâmica , Técnicas Analíticas Microfluídicas/instrumentação
17.
Macromol Rapid Commun ; 34(19): 1554-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23982931

RESUMO

A novel water insoluble, multifunctional poly(ethylene glycol), poly(hydrazide ethylene glycol-co-benzyl glycidyl ether) (P(HZ-co-BnGE)), is synthesized via thiol-ene click reaction of poly(allyl glycidyl ether-co-benzyl glycidyl ether) (P(AGE-co-BnGE)). The base polymer P(AGE-co-BnGE) is previously prepared by anionic ring-opening copolymerization of the corresponding monomers. To demonstrate utility, bicompartmental microspheres and microcylinders containing P(HZ-co-BnGE) in one of the compartments are prepared via electrohydrodynamic (EHD) co-jetting. Next, spatially controlled surface reactivity toward sugars is demonstrated by selective binding of 2α-mannobiose to the P(HZ-co-BnGE) compartment only, as confirmed by a carbohydrate-lectin-binding assay. These sugar-reactive hydrazide-presenting microparticles have potential applications for glyco-targeted drug delivery.


Assuntos
Polietilenoglicóis/química , Química Click , Portadores de Fármacos/química , Ácido Láctico/química , Lectinas/química , Lectinas/metabolismo , Mananas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/síntese química , Polímeros/química
18.
Exp Mol Med ; 55(6): 1099-1109, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37258584

RESUMO

Peptides exhibit lower affinity and a shorter half-life in the body than antibodies. Conversely, peptides demonstrate higher efficiency in tissue penetration and cell internalization than antibodies. Regardless of the pros and cons of peptides, they have been used as tumor-homing ligands for delivering carriers (such as nanoparticles, extracellular vesicles, and cells) and cargoes (such as cytotoxic peptides and radioisotopes) to tumors. Additionally, tumor-homing peptides have been conjugated with cargoes such as small-molecule or chemotherapeutic drugs via linkers to synthesize peptide-drug conjugates. In addition, peptides selectively bind to cell surface receptors and proteins, such as immune checkpoints, receptor kinases, and hormone receptors, subsequently blocking their biological activity or serving as hormone analogs. Furthermore, peptides internalized into cells bind to intracellular proteins and interfere with protein-protein interactions. Thus, peptides demonstrate great application potential as multifunctional players in cancer therapy.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Peptídeos/uso terapêutico , Peptídeos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Receptores de Superfície Celular , Hormônios
19.
Exp Mol Med ; 55(5): 1033-1045, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37121980

RESUMO

Memory-phenotype (MP) CD4+ T cells are a substantial population of conventional T cells that exist in steady-state mice, yet their immunological roles in autoimmune disease remain unclear. In this work, we unveil a unique phenotype of MP CD4+ T cells determined by analyzing single-cell transcriptomic data and T cell receptor (TCR) repertoires. We found that steady-state MP CD4+ T cells in the spleen were composed of heterogeneous effector subpopulations and existed regardless of germ and food antigen exposure. Distinct subpopulations of MP CD4+ T cells were specifically activated by IL-1 family cytokines and STAT activators, revealing that the cells exerted TCR-independent bystander effector functions similar to innate lymphoid cells. In particular, CCR6high subpopulation of MP CD4+ T cells were major responders to IL-23 and IL-1ß without MOG35-55 antigen reactivity, which gave them pathogenic Th17 characteristics and allowed them to contribute to autoimmune encephalomyelitis. We identified that Bhlhe40 in CCR6high MP CD4+ T cells as a key regulator of GM-CSF expression through IL-23 and IL-1ß signaling, contributing to central nervous system (CNS) pathology in experimental autoimmune encephalomyelitis. Collectively, our findings reveal the clearly distinct effector-like heterogeneity of MP CD4+ T cells in the steady state and indicate that CCR6high MP CD4+ T cells exacerbate autoimmune neuroinflammation via the Bhlhe40/GM-CSF axis in a bystander manner.


Assuntos
Encefalomielite Autoimune Experimental , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Camundongos , Animais , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Imunidade Inata , Doenças Neuroinflamatórias , Encefalomielite Autoimune Experimental/metabolismo , Células Th17 , Interleucina-23 , Fenótipo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos , Camundongos Endogâmicos C57BL , Proteínas de Homeodomínio/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
20.
Emerg Microbes Infect ; 11(1): 2176-2183, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35976165

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV) was reported in China in 2017 and is a causative agent of porcine enteric disease. Recent studies indicate that cells from various hosts are susceptible to SADS-CoV, suggesting the zoonotic potential of this virus. However, little is known about the mechanisms through which this virus enters cells. In this study, we investigated the role of furin in SADS-CoV spike (S)-mediated cell - cell fusion and entry. We found that the SADS-CoV S protein induced the fusion of various cells. Cell - cell fusion was inhibited by the proprotein convertase inhibitor dec-RVKR-cmk, and between cells transfected with mutant S proteins resistant to furin cleavage. These findings revealed that furin-induced cleavage of the SADS-CoV S protein is required for cell - cell fusion. Using mutagenesis analysis, we demonstrated that furin cleaves the SADS-CoV S protein near the S1/S2 cleavage site, 446RYVR449 and 543AVRR546. We used pseudotyped viruses to determine whether furin-induced S cleavage is also required for viral entry. Pseudotyped viruses expressing S proteins with a mutated furin cleavage site could be transduced into target cells, indicating that furin-induced cleavage is not required for pseudotyped virus entry. Our data indicate that S cleavage is critical for SADS-CoV S-mediated cell - cell fusion and suggest that furin might be a host target for SADS-CoV antivirals.


Assuntos
Furina , Glicoproteína da Espícula de Coronavírus , Alphacoronavirus , Animais , Antivirais , Fusão Celular , Furina/metabolismo , Pró-Proteína Convertases , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Suínos , Internalização do Vírus
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