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1.
J Cutan Pathol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923071

RESUMO

The potential adverse health effects of antiperspirant use are of interest to patients, primary care providers, dermatologists, and pathologists. In rare instances, antiperspirants containing aluminum-zirconium complexes have been associated with granulomatous dermatoses despite being deemed non-sensitizing in experiments. In this case study, we present a detailed examination of an axillary granuloma in a 28-year-old female who had been using an aluminum-zirconium-based antiperspirant for several years and presented with a left axillary nodule that was excised and analyzed using scanning electron microscopy with energy-dispersive x-ray analysis (SEM/EDXA). Histopathological examination revealed a foreign body-type reaction with amphophilic granular material within giant cells that corresponded to collocated zirconium and aluminum on SEM/EDXA elemental maps. Our case adds to the limited reports of axillary granulomas related to aluminum-zirconium complexes. It illustrates the histopathological appearance and in situ distribution of the aluminum-zirconium complexes, supporting the formation of foreign body-type granulomas. Additionally, our case study illustrates the potential role of these compounds in such reactions and aims to increase awareness among pathologists and clinicians.

2.
Am J Dermatopathol ; 46(3): 155-158, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153266

RESUMO

ABSTRACT: Localized cutaneous argyria is a rare condition caused by the accumulation of silver particles in the skin, leading to blue-gray discoloration. Argyria may mimic melanoma and lead to misdiagnosis. We present a patient with a history of melanoma that developed a blue-gray nodule at a prior melanoma graft. The diagnosis was confirmed using scanning electron microscopy and energy dispersive x-ray analysis. These techniques differentiate argyria from melanoma and can be performed on formalin-fixed, paraffin-embedded, tissue sections. Health care providers should be alert that argyria may mimic recurrent melanoma in patients unaware of silver exposure.


Assuntos
Argiria , Melanoma , Humanos , Argiria/diagnóstico , Argiria/etiologia , Prata , Melanoma/complicações , Raios X , Microscopia Eletrônica de Varredura , Recidiva Local de Neoplasia/complicações
3.
Alzheimers Dement ; 20(6): 4331-4341, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38706421

RESUMO

Ongoing assessment of patients with Alzheimer's disease (AD) in postapproval studies is important for mapping disease progression and evaluating real-world treatment effectiveness and safety. However, interpreting outcomes in the real world is challenging owing to variation in data collected across centers and specialties and greater heterogeneity of patients compared with trial participants. Here, we share considerations for observational postapproval studies designed to collect harmonized longitudinal data from individuals with mild cognitive impairment or mild dementia stage of disease who receive therapies targeting the underlying pathological processes of AD in routine practice. This paper considers key study design parameters, including proposed aims and objectives, study populations, approaches to data collection, and measures of cognition, functional abilities, neuropsychiatric status, quality of life, health economics, safety, and drug utilization. Postapproval studies that capture these considerations will be important to provide standardized data on AD treatment effectiveness and safety in real-world settings.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/terapia , Disfunção Cognitiva , Projetos de Pesquisa , Qualidade de Vida , Estudos Observacionais como Assunto , Progressão da Doença
4.
Angew Chem Int Ed Engl ; 62(8): e202218208, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36584349

RESUMO

Immobilization of porphyrin complexes into crystalline metal-organic frameworks (MOFs) enables high exposure of porphyrin active sites for CO2 electroreduction. Herein, well-dispersed iron-porphyrin-based MOF (PCN-222(Fe)) on carbon-based electrodes revealed optimal turnover frequencies for CO2 electroreduction to CO at 1 wt.% catalyst loading, beyond which the intrinsic catalyst activity declined due to CO2 mass transport limitations. In situ Raman suggested that PCN-222(Fe) maintained its structure under electrochemical bias, permitting mechanistic investigations. These revealed a stepwise electron transfer-proton transfer mechanism for CO2 electroreduction on PCN-222(Fe) electrodes, which followed a shift from a rate-limiting electron transfer to CO2 mass transfer as the potential increased from -0.6 V to -1.0 V vs. RHE. Our results demonstrate how intrinsic catalytic investigations and in situ spectroscopy are needed to elucidate CO2 electroreduction mechanisms on PCN-222(Fe) MOFs.

5.
J Cutan Pathol ; 49(6): 570-574, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35020219

RESUMO

Dystrophic calcification is a common histopathologic finding that can be concomitant with a plethora of diseases, ranging from self-limited infections to insidious malignancies. Gamna-Gandy bodies (GGBs) are a form of dystrophic calcification associated with chronic hemolysis and are typically observed in the spleen. In this report, we present the case of a 92-year-old man who presented with a 4-mm blue papule that was biopsied given the concern for a blue nevus. The subsequent histopathologic examination of the biopsy specimen showed a dermal organizing hematoma adjacent to pale-yellow to brown, refractile material within fibrotic collagen consistent with GGBs. Scanning electron microscopy with energy-dispersive x-ray analysis (SEM/EDXA) revealed that the structures were composed of carbon (39%), oxygen (32%), iron (16%), phosphorus (7%), calcium (5%), and sodium (1%). Fourier transform infrared spectroscopy identified amorphous calcium phosphate. GGBs have not been previously described in the skin and have been rarely characterized with SEM/EDXA in other sites.


Assuntos
Calcinose , Baço , Idoso de 80 Anos ou mais , Calcinose/patologia , Cálcio , Humanos , Masculino , Baço/patologia
6.
Biochem J ; 478(23): 4071-4092, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34871367

RESUMO

The COVID-19 pandemic reminds us that in spite of the scientific progress in the past century, there is a lack of general antiviral strategies. In analogy to broad-spectrum antibiotics as antibacterial agents, developing broad spectrum antiviral agents would buy us time for the development of vaccines and treatments for future viral infections. In addition to targeting viral factors, a possible strategy is to understand host immune defense mechanisms and develop methods to boost the antiviral immune response. Here we summarize the role of NAD+-consuming enzymes in the immune defense against viral infections, with the hope that a better understanding of this process could help to develop better antiviral therapeutics targeting these enzymes. These NAD+-consuming enzymes include PARPs, sirtuins, CD38, and SARM1. Among these, the antiviral function of PARPs is particularly important and will be a focus of this review. Interestingly, NAD+ biosynthetic enzymes are also implicated in immune responses. In addition, many viruses, including SARS-CoV-2 contain a macrodomain-containing protein (NSP3 in SARS-CoV-2), which serves to counteract the antiviral function of host PARPs. Therefore, NAD+ and NAD+-consuming enzymes play crucial roles in immune responses against viral infections and detailed mechanistic understandings in the future will likely facilitate the development of general antiviral strategies.


Assuntos
Antivirais/uso terapêutico , Imunidade Inata , NAD/metabolismo , Viroses/tratamento farmacológico , ADP-Ribosil Ciclase 1/metabolismo , Proteínas do Domínio Armadillo/metabolismo , COVID-19/imunologia , Proteínas do Citoesqueleto/metabolismo , Humanos , NAD/imunologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Domínios Proteicos , SARS-CoV-2 , Sirtuínas/metabolismo , Proteínas não Estruturais Virais/metabolismo , Viroses/imunologia , Tratamento Farmacológico da COVID-19
7.
Lung ; 199(4): 345-355, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34363506

RESUMO

PURPOSE: To document and compare prevalences of pulmonary pathology diagnoses among US Service members deployed during the Global War on Terrorism and non-deployed US service members. Difficulties establishing associations between deployment-related exposures and pulmonary pathology reported among US military service members deployed during the Global War on Terrorism include retrospective estimations of exposures, documenting medical outcomes and lack of comparison groups. METHODS: Pulmonary diagnoses reported between 2002 and 2015 were identified from the records of the former Armed Forces Institute of Pathology and The Joint Pathology Center. Military service and deployment were confirmed by the Defense Manpower Data Center. Diagnoses were reviewed and coded due to variations in diagnostic terminology. Propensity matching and adjusted binomial modeling were applied to comparisons between the deployed and non-deployed to address possible confounding variables. RESULTS: 404 deployed and 2006 non-deployed service members were included. Demographic differences and the date of pathology report complicate unadjusted comparisons. The deployed had no significant increased prevalence of neoplastic conditions. Propensity matching identified a significant increased prevalence of organizing pneumonia in the non-deployed. An adjusted binomial model identified significant increased prevalences of small airways disease, constrictive bronchiolitis and hypersensitivity pneumonitis in the deployed. Both diagnoses were strongly associated with the date of pathology report. Small airways disease, constrictive bronchiolitis comprised 5% of deployed surgical lung biopsy diagnoses. CONCLUSION: This is the largest study of post-deployment pulmonary pathology diagnoses to date, and contains a comparison group. It provides context for studies of pulmonary outcomes among the deployed.


Assuntos
Militares , Terrorismo , Humanos , Pulmão , Prevalência , Estudos Retrospectivos , Estados Unidos/epidemiologia
8.
Plant Cell ; 28(1): 28-41, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26704382

RESUMO

Vegetative phase change in flowering plants is regulated by a decrease in the level of miR156. The molecular mechanism of this temporally regulated decrease in miR156 expression is still unknown. Most of the miR156 in Arabidopsis thaliana shoots is produced by MIR156A and MIR156C. We found that the downregulation of these genes during vegetative phase change is associated with an increase in their level of histone H3 lysine 27 trimethylation (H3K27me3) and requires this chromatin modification. The increase in H3K27me3 at MIR156A/MIR156C is associated with an increase in the binding of PRC2 to these genes and is mediated redundantly by the E(z) homologs SWINGER and CURLY LEAF. The CHD3 chromatin remodeler PICKLE (PKL) promotes the addition of H3K27me3 to MIR156A/MIR156C but is not responsible for the temporal increase in this chromatin mark. PKL is bound to the promoters of MIR156A/MIR156C, where it promotes low levels of H3K27ac early in shoot development and stabilizes the nucleosome at the +1 position. These results suggest a molecular mechanism for the initiation and maintenance of vegetative phase change in plants.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Acetilação , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Metilação , MicroRNAs/genética , MicroRNAs/metabolismo , Nucleossomos/metabolismo , Ligação Proteica/genética , Proteínas Repressoras/metabolismo , Transcrição Gênica
9.
J Toxicol Environ Health A ; 81(20): 1083-1097, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30373484

RESUMO

A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents have been monitored in a clinical surveillance program since 1993. During the spring of 2017, 42 members of the cohort were evaluated with a protocol which includes exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes including measures of bone metabolism, and for participants >50 years, bone mineral density (BMD) determination. Elevated urine U concentrations were observed in cohort members with retained DU shrapnel fragments. Only the mean serum estradiol concentration, a marker of bone metabolism, was found to be significantly different for lower-vs- higher urine U (uU) cohort sub-groups. For the first time, a significant deficit in BMD was observed in the over age 50, high uU sub-group. After more than 25 years since first exposure to DU, an aging cohort of military veterans continues to exhibit few U-related adverse health effects in known target organs of U toxicity. The new finding of reduced BMD in older cohort members, while biologically plausible, was not suggested by other measures of bone metabolism in the full (all ages) cohort, as these were predominantly within normal limits over time. Only estradiol was recently found to display a difference as a function of uU grouping. As BMD is further impacted by aging and the U-burden from fragment absorption accrues in this cohort, a U effect may be clarified in future surveillance visits.


Assuntos
Osso e Ossos/efeitos da radiação , Guerra do Golfo , Exposição Ocupacional/efeitos adversos , Urânio/efeitos adversos , Veteranos/estatística & dados numéricos , Estudos de Coortes , Monitoramento Epidemiológico , Humanos , Masculino , Pessoa de Meia-Idade , Urânio/urina
10.
J Invertebr Pathol ; 157: 4-8, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30003922

RESUMO

Unusual inclusion bodies occur within the epithelial cells of the digestive gland of queen conch, Lobatus gigas, and have previously been described as apicomplexan parasites. The aim of this study was to investigate the parasitic features of these inclusion bodies in queen conch. L. gigas from St. Kitts (Caribbean Sea) consistently (100% of n = 61) showed large numbers of ovoid to tri-bulbous dark brown inclusion bodies (15 × 30 µm) within vacuolar cells. Histochemical stains demonstrated iron, melanin, and glycoprotein and/or mucopolysaccharide within the inclusion bodies. Microscopic features indicative of a host response to injury were lacking in every case, as were consistent morphological forms to indicate distinct parasitic stages. Transmission electron microscopy failed to reveal cellular organelles of parasitic organisms and DNA extractions of purified inclusion bodies did not yield sufficient concentrations for successful PCR amplification. Scanning electron microscopy with energy dispersive X-ray analysis revealed a number of elements, particularly iron, within the inclusion bodies. We conclude that the inclusion bodies are not an infectious agent, and hypothesize that they represent a storage form for iron, and potentially other elements, within a protein matrix. Similar structures have been described in the digestive glands of other invertebrates, including prosobranchs.


Assuntos
Sistema Digestório/patologia , Gastrópodes/ultraestrutura , Corpos de Inclusão/patologia , Animais , Região do Caribe , Sistema Digestório/ultraestrutura , Corpos de Inclusão/ultraestrutura
11.
Cardiovasc Ultrasound ; 15(1): 18, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28673293

RESUMO

BACKGROUND: Left ventricular outflow tract velocity time integral (LVOT VTI) is a measure of cardiac systolic function and cardiac output. Heart failure patients with low cardiac output are known to have poor cardiovascular outcomes. Thus, extremely low LVOT VTI may predict heart failure patients at highest risk for mortality. METHODS: Patients with heart failure and extremely low LVOT VTI were identified from a single-center database. Baseline characteristics and heart failure related clinical outcomes (death, LVAD) were obtained at 12 months. Correlation between clinical endpoints and the following variables were analyzed: ejection fraction (EF), pulmonary artery systolic pressure (PASP), NYHA class, renal function, Doppler cardiac output (CO), and LVOT VTI. RESULTS: Study cohort consisted of 100 patients. At the 12-month follow up period, 30 events (28 deaths, 2 LVADs) were identified. Occurrence of death and LVAD implantation was statistically associated with a lower LVOT VTI (p = 0.039) but not EF (p = 0.169) or CO (p = 0.217). In multivariate analysis, LVOT VTI (p = 0.003) remained statistically significant, other significant variables were age (p = 0.033) and PASP (p = 0.022). Survival analysis by LVOT VTI tertile demonstrated an unadjusted hazard ratio of 4.755 (CI 1.576-14.348, p = 0.006) for combined LVAD and mortality at one year. CONCLUSIONS: Extremely low LVOT VTI strongly predicts adverse outcomes and identifies patients who may benefit most from advanced heart failure therapies.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia Doppler/métodos , Insuficiência Cardíaca/diagnóstico , Ventrículos do Coração/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , California/epidemiologia , Causas de Morte/tendências , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Prognóstico , Taxa de Sobrevida/tendências , Sístole
12.
Lung ; 195(4): 507-515, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28536739

RESUMO

INTRODUCTION: The current understanding of associations between lung disease and military deployment to Southwest Asia, including Iraq and Afghanistan, is both controversial and limited. We sought to clarify the relation between military deployment and biopsy-proven lung disease. METHODS: Retrospective data were analyzed for military personnel with non-neoplastic lung biopsies evaluated at the Armed Forces Institute of Pathology or Joint Pathology Center (January 2005 to December 2012). RESULTS: Of 391 subjects, 137 (35.0%) had deployed to Southwest Asia prior to biopsy. Compared to non-deployed subjects, those deployed were younger (median age 37 vs. 51 years) with higher representation of African Americans (30.0 vs. 16.9%). Deployed patients were more likely diagnosed with non-necrotizing granulomas (OR 2.4). Non-deployed subjects had higher frequency of idiopathic interstitial pneumonias, particularly organizing pneumonia. Prevalence of small airways diseases including constrictive bronchiolitis was low. CONCLUSIONS: This study provides a broader understanding of diversity of biopsy-proven non-neoplastic lung disease as it relates to military deployment to Southwest Asia and importantly did not show an increased prevalence of small airway disease to include constrictive bronchiolitis.


Assuntos
Pneumopatias/patologia , Pulmão/patologia , Militares , Adolescente , Adulto , Negro ou Afro-Americano , Biópsia , Bronquiolite Obliterante/etnologia , Bronquiolite Obliterante/patologia , Distribuição de Qui-Quadrado , Feminino , Granuloma do Sistema Respiratório/etnologia , Granuloma do Sistema Respiratório/patologia , Humanos , Pneumonias Intersticiais Idiopáticas/etnologia , Pneumonias Intersticiais Idiopáticas/patologia , Modelos Logísticos , Pneumopatias/etnologia , Masculino , Pessoa de Meia-Idade , Oriente Médio , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia , População Branca , Adulto Jovem
13.
Soc Sci Res ; 66: 140-153, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28705352

RESUMO

In this paper we use data on consecutive cohorts of recent graduates from community colleges or community college-like institutions to address the following questions about the gender earnings gap: i) What was the trend in the gender earnings gap for these recent graduates? ii) What role in the observed trends in the gender earnings gap was played by occupational demand? iii) How and to what extent did the domestic division of labour contribute to the gender earnings gap in this young sample? We find that the gap fell then rose, that occupational demand played a role in these shifts, and that the domestic division of labour did indeed contribute to the gap in this young sample. Furthermore, our results point to a process of cumulation of factors that increase the earnings gap which has both substantive and methodological implications.

14.
J Cutan Pathol ; 42(8): 568-73, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25950356

RESUMO

Localized chrysiasis is rare and can occur in two settings: after localized or traumatic implantation of elemental gold or gold salts or after localized laser or light therapy in someone who has been previously exposed to systemic gold therapy. We report a unique case of localized chrysiasis with associated aluminum salt deposition and sclerosing lipogranulomas because of previous injections of aurothioglucose (Solganal®). The unique histopathologic findings seen in this case have not been previously reported.


Assuntos
Alumínio/metabolismo , Aurotioglucose/efeitos adversos , Calcinose/induzido quimicamente , Granuloma/induzido quimicamente , Idoso , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Aurotioglucose/administração & dosagem , Calcinose/metabolismo , Calcinose/patologia , Feminino , Granuloma/metabolismo , Granuloma/patologia , Humanos , Síndrome de Sjogren/tratamento farmacológico
15.
Catheter Cardiovasc Interv ; 83(4): 664-9, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24214652

RESUMO

Left atrial appendage (LAA) occlusion or ligation is a novel approach to stroke prevention in atrial fibrillation that may obviate the need for long-term anticoagulation. The Lariat device has received Food and Drug Administration 510K clearance for the approximation of soft tissue and has been applied to transcatheter LAA ligation using a combined trans-pericardial and transseptal approach. The occurrence of late leak after transcatheter LAA ligation and its percutaneous management has not been previously reported. Herein, we report three cases of late leak with reconstitution of the LAA after initially successful Lariat closure, and present a simple percutaneous technique for leak closure.


Assuntos
Apêndice Atrial , Fibrilação Atrial/terapia , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Acidente Vascular Cerebral/prevenção & controle , Idoso , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Ecocardiografia Doppler em Cores , Ecocardiografia Transesofagiana , Humanos , Ligadura , Masculino , Pessoa de Meia-Idade , Radiografia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
16.
PLoS One ; 19(4): e0301868, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38603724

RESUMO

The role that inhaled particulate matter plays in the development of post-deployment lung disease among US service members deployed to Southwest Asia during the Global War on Terrorism has been difficult to define. There is a persistent gap in data addressing the relationship between relatively short-term (months to a few years) exposures to high levels of particulate matter during deployment and the subsequent development of adverse pulmonary outcomes. Surgical lung biopsies from deployed service members and veterans (DSMs) and non-deployed service members and veterans (NDSMs) who develop lung diseases can be analyzed to potentially identify residual deployment-specific particles and develop associations with pulmonary pathological diagnoses. We examined 52 surgical lung biopsies from 25 DSMs and 27 NDSMs using field emission scanning electron microscopy (FE-SEM) with energy dispersive x-ray spectroscopy (EDS) to identify any between-group differences in the number and composition of retained inorganic particles, then compared the particle analysis results with the original histopathologic diagnoses. We recorded a higher number of total particles in biopsies from DSMs than from NDSMs, and this difference was mainly accounted for by geologic clays (illite, kaolinite), feldspars, quartz/silica, and titanium-rich silicate mixtures. Biopsies from DSMs deployed to other Southwest Asia regions (SWA-Other) had higher particle counts than those from DSMs primarily deployed to Iraq or Afghanistan, due mainly to illite. Distinct deployment-specific particles were not identified. Particles did not qualitatively associate with country of deployment. The individual diagnoses of the DSMs and NDSMs were not associated with elevated levels of total particles, metals, cerium oxide, or titanium dioxide particles. These results support the examination of particle-related lung disease in DSMs in the context of comparison groups, such as NDSMs, to assist in determining the strength of associations between specific pulmonary pathology diagnoses and deployment-specific inorganic particulate matter exposure.


Assuntos
Pneumopatias , Militares , Minerais , Terrorismo , Humanos , Pulmão/patologia , Pneumopatias/patologia , Material Particulado , Biópsia
17.
Development ; 137(1): 113-22, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20023166

RESUMO

The Arabidopsis embryo becomes patterned into central and peripheral domains during the first few days after fertilization. A screen for mutants that affect this process identified two genes, GRAND CENTRAL (GCT)and CENTER CITY (CCT). Mutations in GCT and CCT delay the specification of central and peripheral identity and the globular-to-heart transition, but have little or no effect on the initial growth rate of the embryo. Mutant embryos eventually recover and undergo relatively normal patterning, albeit at an inappropriate size. GCT and CCT were identified as the Arabidopsis orthologs of MED13 and MED12 - evolutionarily conserved proteins that act in association with the Mediator complex to negatively regulate transcription. The predicted function of these proteins combined with the effect of gct and cct on embryo development suggests that MED13 and MED12 regulate pattern formation during Arabidopsis embryogenesis by transiently repressing a transcriptional program that interferes with this process. Their mutant phenotype reveals the existence of a previously unknown temporal regulatory mechanism in plant embryogenesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas Repressoras/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Complexo Mediador/genética , Complexo Mediador/metabolismo , Proteínas Repressoras/genética
18.
Ultrasound Med Biol ; 49(5): 1118-1128, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36732151

RESUMO

OBJECTIVE: The opening of the blood-brain barrier (BBB) to allow therapeutic drug passage can be achieved by inducing microbubble cavitation using focused ultrasound (FUS). This approach can be monitored through analysis of the received signal to distinguish between stable cavitation associated with safe BBB opening and inertial cavitation associated with blood vessel damage. In this study, FUS phantom and animal studies were used to evaluate the experimental conditions that generate several cross-consistent metrics having the potential to be combined for the reliable, automatic control of cavitation levels. METHODS: Typical metrics for cavitation monitoring involve observing changes in the spectrum generated by applying the discrete Fourier transform (DFT) to the time domain signal detected using a hydrophone during FUS. A confocal hydrophone was used to capture emissions during a 10 ms FUS burst, sampled at 32 ns intervals, to produce 321,500 points and a high-resolution spectrum when transformed. The FUS spectra were analyzed to show the impact that equipment-transients and well-known DFT-related distortions had on the metrics used for cavitation control. A new approach, physical sparsification (PH-SP), was introduced to sharpen FUS spectral peaks and minimize the effect of these distortions. DISCUSSION: It was demonstrated that the general spectral signal-to-noise ratio (SNR) could be improved by removing the initial noisy phantom hydrophone signal transient. Minor changes in the transient length digitally removed from the sampled values significantly changed the spectral bandwidths of all the harmonically related FUS signals. We evaluated signal processing techniques to minimize the impact these DFT-related distortions on area-under-the-curve (AUC) metric calculations, and we identified the advantages of using PH-SP and proposed new metrics when characterizing FUS spectral properties. The results show many second, third and sub-harmonic metrics provide cross-consistent evidence of changes between stable and inertial cavitation levels. Removing the first harmonic signal component with a hardware low-pass filter allowed the hydrophone gain to be boosted without introducing distortion, leading to an improved analysis of the sub-harmonic signal orders of magnitude smaller in intensity. Metrics that optimized the energy in the real component of the complex-valued PH-SP spectra provided a 32% increase in the sub-harmonic sensitivity compared to standard metrics. CONCLUSION: A preliminary investigation of existing and proposed metrics showed that system noise could be large enough to mask the transition between stable and inertial cavitation. Strong narrowing of sub-harmonic peak shapes on applying physical sparsification (PH-SP) were seen in both phantom and animal studies. However, validating equivalent trends of the metrics with pressure were limited by the increased system noise level in the animal study combined with the natural variability between subjects studied. The combined use of hardware low-pass filters and physical sparsification to selectively removing distortions in the spectrum allowed the optimization of metrics for cavitation monitoring by improving the sub-harmonic sensitivity.


Assuntos
Benchmarking , Barreira Hematoencefálica , Animais , Microbolhas , Imagens de Fantasmas , Processamento de Sinais Assistido por Computador
19.
ACS Cent Sci ; 9(5): 980-991, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37252359

RESUMO

Maintaining homeostasis of metabolites such as amino acids is critical for cell survival. Dysfunction of nutrient balance can result in human diseases such as diabetes. Much remains to be discovered about how cells transport, store, and utilize amino acids due to limited research tools. Here we developed a novel, pan-amino acid fluorescent turn-on sensor, NS560. It detects 18 of the 20 proteogenic amino acids and can be visualized in mammalian cells. Using NS560, we identified amino acids pools in lysosomes, late endosomes, and surrounding the rough endoplasmic reticulum. Interestingly, we observed amino acid accumulation in large cellular foci after treatment with chloroquine, but not with other autophagy inhibitors. Using a biotinylated photo-cross-linking chloroquine analog and chemical proteomics, we identified Cathepsin L (CTSL) as the chloroquine target leading to the amino acid accumulation phenotype. This study establishes NS560 as a useful tool to study amino acid regulation, identifies new mechanisms of action of chloroquine, and demonstrates the importance of CTSL regulation of lysosomes.

20.
J Occup Environ Med ; 65(8): 670-676, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37167933

RESUMO

OBJECTIVE: In 2021, 37 members of a cohort of depleted uranium-exposed Gulf War I veterans were evaluated using a protocol tailored to accommodate COVID-19 safety practices on a telehealth platform. METHODS: Individual elements of the legacy protocol were reviewed for urgency and feasibility of inclusion in a modified, telehealth platform. RESULTS: The redesigned protocol included a participant readiness for telehealth assessment, nurse and physician telehealth visits, collection of usual health questionnaires, and urine collections for exposure monitoring for uranium and other fragment-related metal measures. CONCLUSIONS: Despite some limitations in scope, the telehealth platform permitted a visual "visit" with surveillance participants who expressed a high comfort level with the format. The telehealth platform has apparent utility for occupational surveillance and should be explored as a standard approach for surveillance outside of public health emergencies.


Assuntos
COVID-19 , Exposição Ocupacional , Telemedicina , Urânio , Veteranos , Humanos , Exposição Ocupacional/análise , Guerra do Golfo
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