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1.
J Cutan Pathol ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923071

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38153266

RESUMEN

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.


Asunto(s)
Argiria , Melanoma , Humanos , Argiria/diagnóstico , Argiria/etiología , Plata , Melanoma/complicaciones , Rayos X , Microscopía Electrónica de Rastreo , Recurrencia Local de Neoplasia/complicaciones
3.
Alzheimers Dement ; 20(6): 4331-4341, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38706421

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/terapia , Disfunción Cognitiva , Proyectos de Investigación , Calidad de Vida , Estudios Observacionales como Asunto , Progresión de la Enfermedad
4.
Angew Chem Int Ed Engl ; 62(8): e202218208, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36584349

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35020219

RESUMEN

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.


Asunto(s)
Calcinosis , Bazo , Anciano de 80 o más Años , Calcinosis/patología , Calcio , Humanos , Masculino , Bazo/patología
6.
Biochem J ; 478(23): 4071-4092, 2021 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-34871367

RESUMEN

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.


Asunto(s)
Antivirales/uso terapéutico , Inmunidad Innata , NAD/metabolismo , Virosis/tratamiento farmacológico , ADP-Ribosil Ciclasa 1/metabolismo , Proteínas del Dominio Armadillo/metabolismo , COVID-19/inmunología , Proteínas del Citoesqueleto/metabolismo , Humanos , NAD/inmunología , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Dominios Proteicos , SARS-CoV-2 , Sirtuinas/metabolismo , Proteínas no Estructurales Virales/metabolismo , Virosis/inmunología , Tratamiento Farmacológico de COVID-19
7.
Lung ; 199(4): 345-355, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34363506

RESUMEN

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.


Asunto(s)
Personal Militar , Terrorismo , Humanos , Pulmón , Prevalencia , Estudios Retrospectivos , Estados Unidos/epidemiología
8.
Plant Cell ; 28(1): 28-41, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26704382

RESUMEN

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.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Acetilación , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Metilación , MicroARNs/genética , MicroARNs/metabolismo , Nucleosomas/metabolismo , Unión Proteica/genética , Proteínas Represoras/metabolismo , Transcripción Genética
9.
J Toxicol Environ Health A ; 81(20): 1083-1097, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30373484

RESUMEN

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.


Asunto(s)
Huesos/efectos de la radiación , Guerra del Golfo , Exposición Profesional/efectos adversos , Uranio/efectos adversos , Veteranos/estadística & datos numéricos , Estudios de Cohortes , Monitoreo Epidemiológico , Humanos , Masculino , Persona de Mediana Edad , Uranio/orina
10.
J Invertebr Pathol ; 157: 4-8, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30003922

RESUMEN

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.


Asunto(s)
Sistema Digestivo/patología , Gastrópodos/ultraestructura , Cuerpos de Inclusión/patología , Animales , Región del Caribe , Sistema Digestivo/ultraestructura , Cuerpos de Inclusión/ultraestructura
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